Geneticist, Neurologists
30 years of experience
Video profile
Accepting new patients
Northeast Ann Arbor
Ann Arbor Veterans Affairs Medical Center
2215 Fuller Rd
Ann Arbor, MI 48105
734-769-7100
Locations and availability (4)

Education ?

Medical School
Medical College of Ohio (1980)

Awards & Distinctions ?

Awards  
One of America's Leading Experts on:
Hereditary Spastic Paraplegia
Patients' Choice Award (2011 - 2012)
Compassionate Doctor Recognition (2011 - 2012)
Associations
American Board of Psychiatry and Neurology
American Board of Medical Genetics

Affiliations ?

Dr. Fink is affiliated with 3 hospitals.

Hospital Affilations

Score

Rankings

  • University of Michigan Hospitals & Health Centers
    1500 E Medical Center Dr, Ann Arbor, MI 48109
    • Currently 4 of 4 crosses
    Top 25%
  • University of Michigan Health System
  • Ann Arbor Veterans Affairs Medical Center
    2215 Fuller Rd, Ann Arbor, MI 48105
  • Publications & Research

    Dr. Fink has contributed to 78 publications.
    Title Motor Neuron Disease Due to Neuropathy Target Esterase Gene Mutation: Clinical Features of the Index Families.
    Date January 2011
    Journal Muscle & Nerve
    Excerpt

    Recently, we reported that mutations in the neuropathy target esterase (NTE) gene cause autosomal recessive motor neuron disease (NTE-MND). We describe clinical, neurophysiologic, and neuroimaging features of affected subjects in the index families. NTE-MND subjects exhibited progressive lower extremity spastic weakness that began in childhood and was later associated with atrophy of distal leg and intrinsic hand muscles. NTE-MND resembles Troyer syndrome, except that short stature, cognitive impairment, and dysmorphic features, which often accompany Troyer syndrome, are not features of NTE-MND. Early onset, symmetry, and slow progression distinguish NTE-MND from typical amyotrophic lateral sclerosis. NTE is implicated in organophosphorus compound-induced delayed neurotoxicity (OPIDN). NTE-MND patients have upper and lower motor neuron deficits that are similar to OPIDN. Motor neuron degeneration in subjects with NTE mutations supports the role of NTE and its biochemical cascade in the molecular pathogenesis of OPIDN and possibly other degenerative neurologic disorders.

    Title Myelopolyneuropathy and Pancytopenia Due to Copper Deficiency and High Zinc Levels of Unknown Origin Ii. The Denture Cream is a Primary Source of Excessive Zinc.
    Date March 2010
    Journal Neurotoxicology
    Excerpt

    Neurodegeneration of the central and peripheral nervous system associated with hypocupremia and hyperzincinemia has been widely recognized but the origin of high zinc remained unknown. Denture cream has been recently suggested as one possible source of zinc, but the frequency with which denture fixative alone accounts for this syndrome is unknown. We analyzed the origin of excessive zinc in eleven patients with a progressive myelopolyneuropathy and unexplained hypocupremia with hyperzincinemia. These patients had a detailed clinical assessment, determination of zinc and copper levels, and analyzed use of denture cream with the estimates of daily zinc exposure. We identified denture cream as a source of excessive zinc in 100% patients in our cohort. They all had a history of ill-fitting dentures requiring large amounts of denture cream, resulting in significant zinc exposure. Their copper and zinc normalized after stopping denture cream, further confirming that this is the source of high zinc. Inappropriate use of denture cream appears to be the sole source of excessive zinc in these patients.

    Title Treatment of Wilson's Disease with Tetrathiomolybdate: V. Control of Free Copper by Tetrathiomolybdate and a Comparison with Trientine.
    Date September 2009
    Journal Translational Research : the Journal of Laboratory and Clinical Medicine
    Excerpt

    It has become clear that serum "free" copper (the copper not bound to ceruloplasmin in the blood) is the copper causing copper toxicity in Wilson's disease. But up until now, free copper has not been closely followed during initiation of anticopper therapy in neurologically presenting patients. During this period of initial therapy, the future fate of these patients hangs in the balance-if they worsen neurologically as often happens with penicillamine or trientine therapy, many never recover. We hypothesize that free copper levels are a biological marker of clinical outcome in these patients. In this article, we evaluate the control of free copper in 3 studies of initial anticopper treatment in neurologically presenting Wilson's disease patients. The first (study 1) is a 55-patient open-label trial of tetrathiomolybdate, the second (study 2) is a 48-patient double-blind trial comparing tetrathiomolybdate and trientine, and the third (study 3) is a 40-patient double-blind comparison of 2 disease regimens of tetrathiomolybdate. Free copper levels were determined by subtracting ceruloplasmin and tetrathiomolybdate bound copper from total serum copper. Tetrathiomolybdate showed very strong control of free copper levels over the 8 weeks of treatment in the 55-patient open-label study (study 1), reducing it to a mean value of about one fourth, or less, of baseline. In the tetrathiomolybdate/trientine double blind (study 2), tetrathiomolybdate again showed good control of free copper levels over 8 weeks of treatment, which is significantly better than trientine. In the trientine arm of study 2, mean free copper levels actually went up during trientine therapy. The 5 patients who neurologically worsened on trientine therapy over 8 weeks of treatment showed significant spikes in serum free copper levels associated in time with their neurologic worsening. Patients who did not worsen neurologically generally did not show significant spikes in free copper. Tetrathiomolybdate controlled copper less well in the dose regimen study (study 3) than in the previous 2 studies of tetrathiomolybdate treatment, probably because of a change in the way "away from food" tetrathiomolybdate was given.

    Title Neuropathy Target Esterase Gene Mutations Cause Motor Neuron Disease.
    Date March 2008
    Journal American Journal of Human Genetics
    Excerpt

    The possibility that organophosphorus (OP) compounds contribute to motor neuron disease (MND) is supported by association of paraoxonase 1 polymorphisms with amyotrophic lateral sclerosis (ALS) and the occurrence of MND in OP compound-induced delayed neuropathy (OPIDN), in which neuropathy target esterase (NTE) is inhibited by organophosphorylation. We evaluated a consanguineous kindred and a genetically unrelated nonconsanguineous kindred in which affected subjects exhibited progressive spastic paraplegia and distal muscle wasting. Affected subjects resembled those with OPIDN and those with Troyer Syndrome due to SPG20/spartin gene mutation (excluded by genetic linkage and SPG20/spartin sequence analysis). Genome-wide analysis suggested linkage to a 22 cM homozygous locus (D19S565 to D19S884, maximum multipoint LOD score 3.28) on chromosome 19p13 to which NTE had been mapped (GenBank AJ004832). NTE was a candidate because of its role in OPIDN and the similarity of our patients to those with OPIDN. Affected subjects in the consanguineous kindred were homozygous for disease-specific NTE mutation c.3034A-->G that disrupted an interspecies conserved residue (M1012V) in NTE's catalytic domain. Affected subjects in the nonconsanguineous family were compound heterozygotes: one allele had c.2669G-->A mutation, which disrupts an interspecies conserved residue in NTE's catalytic domain (R890H), and the other allele had an insertion (c.2946_2947insCAGC) causing frameshift and protein truncation (p.S982fs1019). Disease-specific, nonconserved NTE mutations in unrelated MND patients indicates NTE's importance in maintaining axonal integrity, raises the possibility that NTE pathway disturbances contribute to other MNDs including ALS, and supports the role of NTE abnormalities in axonopathy produced by neuropathic OP compounds.

    Title Systematic Isolation and Characterization of Cdnas Encoding Aaa Proteins from Human Brain.
    Date June 2007
    Journal Bratislavské Lekárske Listy
    Excerpt

    BACKGROUND: The AAA (ATPases Associated with various cellular Activities) domain characterizes a diverse superfamily of proteins. Mutations in genes encoding AAA-domains cause a variety of human diseases including cystic fibrosis, Zellweger syndrome, adrenomyeloneuropathy, and dystonia. Recently, mutations in two AAA-containing proteins paraplegin and spastin have been shown to cause two types of hereditary spastic paraplegia (HSP). The HSPs are genetically heterogeneous degenerative spinal cord disorders characterized by lower extremity weakness and spasticity. Clinical similarity between various genetic types of HSP led us to propose that different genetic types of HSP were due to common biochemical abnormalities including disturbances in related proteins. For this reason, we sought to identify novel AAA-containing proteins as potential candidates for HSP and related neurodegnerative disorders. We used degenerative PCR, based on the conserved AAA peptide sequence to systematically clone and characterize AAA genes expressed in human brain. RESULTS: We analyzed 646 clones and identified 19 known AAA-containing proteins including spastin and paraplegin, AAA-containing genes that cause HSP. In addition, we identified 14 unique DNA inserts representing novel putative AAA-containing proteins. Four of these novel genes are hypothetical AAA proteins and the rest of novel clones matched sequences of yet uncharacterized expressed sequence tags (ESTs). CONCLUSION: Fourteen novel AAA-containing proteins are potential candidates for human diseases including degenerative neurologic disorders, and their further analysis is ongoing (Tab. 1, Fig. 1, Ref. 22).

    Title Treatment of Wilson Disease with Ammonium Tetrathiomolybdate: Iv. Comparison of Tetrathiomolybdate and Trientine in a Double-blind Study of Treatment of the Neurologic Presentation of Wilson Disease.
    Date May 2006
    Journal Archives of Neurology
    Excerpt

    OBJECTIVE: To compare tetrathiomolybdate and trientine in treating patients with the neurologic presentation of Wilson disease for the frequency of neurologic worsening, adverse effects, and degree of neurologic recovery. DESIGN: A randomized, double-blind, controlled, 2-arm study of 48 patients with the neurologic presentation of Wilson disease. Patients either received 500 mg of trientine hydrochloride 2 times per day or 20 mg of tetrathiomolybdate 3 times per day with meals and 20 mg 3 times per day between meals for 8 weeks. All patients received 50 mg of zinc 2 times per day. Patients were hospitalized for 8 weeks, with neurologic and speech function assessed weekly; discharged taking 50 mg of zinc 3 times per day, and returned annually for follow-up. SETTING: A university hospital referral setting. PATIENTS: Primarily newly diagnosed patients with Wilson disease presenting with neurologic symptoms who had not been treated longer than 4 weeks with an anticopper drug. INTERVENTION: Treatment with either trientine plus zinc or tetrathiomolybdate plus zinc. MAIN OUTCOME MEASURES: Neurologic function was assessed by semiquantitative neurologic and speech examinations. Drug adverse events were evaluated by blood cell counts and biochemical measures. RESULTS: Six of 23 patients in the trientine arm and 1 of 25 patients in the tetrathiomolybdate arm underwent neurologic deterioration (P<.05). Three patients receiving tetrathiomolybdate had adverse effects of anemia and/or leukopenia, and 4 had further transaminase elevations. One patient receiving trientine had an adverse effect of anemia. Four patients receiving trientine died during follow-up, 3 having shown initial neurologic deterioration. Neurologic and speech recovery during a 3-year follow-up period were quite good. CONCLUSION: Tetrathiomolybdate is a better choice than trientine for preserving neurologic function in patients who present with neurologic disease.

    Title De Novo Occurrence of Novel Spg3a/atlastin Mutation Presenting As Cerebral Palsy.
    Date April 2006
    Journal Archives of Neurology
    Excerpt

    BACKGROUND: Mutations in the SPG3A gene (atlastin protein) cause approximately 10% of autosomal-dominant hereditary spastic paraplegia. For many subjects with an SPG3A mutation, spastic gait begins in early childhood and does not significantly worsen even over many years. Such subjects resemble those with spastic diplegic cerebral palsy. To date, only 9 SPG3A mutations have been reported. OBJECTIVE: To analyze the SPG3A coding sequence in an individual with childhood-onset spastic gait, who, prior to the birth of her similarly affected child, had no previous family history of hereditary spastic paraplegia. METHODS: The SPG3A coding sequence was analyzed in DNA samples from the proband, her affected child, her unaffected parents, and control subjects by polymerase-chain-reaction amplification of each exon followed by direct DNA sequencing. Seventeen microsatellite polymorphisms were amplified and analyzed to confirm reported paternity. RESULTS: We identified a novel SPG3A mutation (L157W) in the proband and her affected child. This mutation was absent in the proband's unaffected parents. Results of microsatellite polymorphism analysis were consistent with paternity as reported. These results indicate that this novel SPG3A mutation arose de novo in the proband. CONCLUSIONS: We report the de novo occurrence of a novel SPG3A mutation in a subject with childhood-onset, nonprogressive, spastic diplegia who had no previous family history of hereditary spastic paraplegia until the birth of her similarly affected son. Although rare, the occurrence of a de novo hereditary spastic paraplegia gene mutation must be considered in subjects with spastic diplegic cerebral palsy for whom no other cause is identified. This is extremely important for correct genetic counseling because recurrence risk may be as high as 50% when a mutation is detected.

    Title Hereditary Spastic Paraplegia.
    Date March 2006
    Journal Current Neurology and Neuroscience Reports
    Excerpt

    The hereditary spastic paraplegias (HSPs) comprise a large group of inherited neurologic disorders. HSP is classified according to the mode of inheritance, the HSP locus when known, and whether the spastic paraplegia syndrome occurs alone or is accompanied by additional neurologic or systemic abnormalities. Analysis of 11 recently discovered HSP genes provides insight into HSP pathogenesis. Hereditary spastic paraplegia is a clinical diagnosis for which laboratory confirmation is sometimes possible, and careful exclusion of alternate and co-existing disorders is an important element in HSP diagnosis. Treatment for HSP is presently limited to symptomatic reduction of muscle spasticity, reduction in urinary urgency, and strength and gait improvement through physical therapy. Prenatal genetic testing in HSP is possible for some individuals with the increasing availability of HSP gene analysis.

    Title Spinal Cord Magnetic Resonance Imaging in Autosomal Dominant Hereditary Spastic Paraplegia.
    Date January 2006
    Journal Neuroradiology
    Excerpt

    Hereditary spastic paraplegia (HSP) is a genetically heterogeneous group of neurodegenerative disorders characterized by progressive lower extremity weakness and spasticity. HSP pathology involves axonal degeneration that is most pronounced in the terminal segments of the longest descending (pyramidal) and ascending (dorsal columns) tracts. In this study, we compared spinal cord magnetic resonance imaging (MRI) in 13 HSP patients with four different types of autosomal dominant hereditary spastic paraplegia (SPG3A, SPG4, SPG6, and SPG8) with age-matched control subjects. The cross-section area of HSP subjects at cervical level C2 was 59.42 +/- 12.57 mm2 and at thoracic level T9 was 28.58 +/- 5.25 mm2. Both of these values were less than in the healthy controls (p < 0.001). The degree of cord atrophy was more prominent in patients with SPG6 and SPG8 who had signs of severe cord atrophy (47.60 +/- 6.58 mm2 at C2, 21.40 +/- 2.4 mm2 at T9) than in subjects with SPG3 and SPG4 (66.0 +/- 8.94 mm2 at C2, p < 0.02; 31.75 +/- 2.76 mm2 at T9, p < 0.001). These observations indicate that spinal cord atrophy is a common finding in the four genetic types of HSP. Spinal cord atrophy was more severe in SPG6 and SPG8 HSP subjects than in other types of HSP we studied. This may suggest a different disease mechanism with more prominent axonal degeneration in these two types of HSP when compared with HSP due to spastin and atlastin mutations.

    Title Cerebrotendinous Xanthomatosis: Possible Higher Prevalence Than Previously Recognized.
    Date November 2005
    Journal Archives of Neurology
    Excerpt

    BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is a rare but treatable neurodegenerative disorder caused by 27-sterol hydroxylase (CYP27) deficiency. OBJECTIVE: To describe clinical features and results of genetic analysis in a family with CTX. DESIGN: Case report. SETTING: University hospital.Subjects A 54-year-old woman with CTX, her family members, and 115 white control subjects. MAIN OUTCOME MEASURES: Results of clinical evaluation and magnetic resonance imaging of the brain in the affected subject; results of mutation analysis of the CYP27 coding sequence in the patient, her parents, and the control subjects. RESULTS: The proband and her affected sibling had classic features of CTX, including presenile cataracts, tendon xanthomas, diarrhea, and a complex neurodegenerative disorder. They were somewhat atypical, however, because their cataracts were congenital, cognitive impairment had been noted in childhood, and the white matter involvement was more severe than usual. The proband was shown to be homozygous for CYP27 mutation R362C. Similar analysis of 115 control subjects identified 1 subject who was a heterozygous carrier for this same CYP27 mutation. CONCLUSIONS: The prevalence of CTX due to CYP27 mutation R362C alone is approximately 1 per 50,000 among white individuals. Although the disorder is rare, this incidence is substantially greater than previously recognized. Greater awareness of CTX is important because specific treatment is available.

    Title Mutations in the Slow Skeletal Muscle Fiber Myosin Heavy Chain Gene (myh7) Cause Laing Early-onset Distal Myopathy (mpd1).
    Date December 2004
    Journal American Journal of Human Genetics
    Excerpt

    We previously linked Laing-type early-onset autosomal dominant distal myopathy (MPD1) to a 22-cM region of chromosome 14. One candidate gene in the region, MYH7, which is mutated in cardiomyopathy and myosin storage myopathy, codes for the myosin heavy chain of type I skeletal muscle fibers and cardiac ventricles. We have identified five novel heterozygous mutations--Arg1500Pro, Lys1617del, Ala1663Pro, Leu1706Pro, and Lys1729del in exons 32, 34, 35, and 36 of MYH7--in six families with early-onset distal myopathy. All five mutations are predicted, by in silico analysis, to locally disrupt the ability of the myosin tail to form the coiled coil, which is its normal structure. These findings demonstrate that heterozygous mutations toward the 3' end of MYH7 cause Laing-type early-onset distal myopathy. MYH7 is the fourth distal-myopathy gene to have been identified.

    Title Porphyric Neuropathy.
    Date October 2004
    Journal Muscle & Nerve
    Excerpt

    The hepatic porphyrias are a group of rare metabolic disorders characterized by enzymatic defects in the biosynthesis of heme, a metalloporphyrin that is the principal product of porphyrin metabolism. The hepatic porphyrias are genetically transmitted as autosomal-dominant disorders with variable expression that produce a particularly severe form of neuropathy. Most medical students readily recognize acute attacks of porphyria when the classic triad of abdominal pain, psychosis, and neuropathy is present. Yet, porphyric neuropathy is a source of confusion in practice, and patients with porphyria rarely receive the correct diagnosis early in the course of the illness. Porphyric neuropathy is manifest by symptoms, signs, and cerebrospinal fluid abnormalities resembling acute Guillain-Barré syndrome. However, accompanying psychological features, a proximal predilection of asymmetric weakness, and electrodiagnostic findings indicative of an axonal polyradiculopathy or neuronopathy all suggest the diagnosis of porphyria. Confirmation of the diagnosis depends on use of appropriate laboratory studies. The underlying pathophysiology of porphyric neuropathy has not been established, but it may be related to direct neurotoxicity of elevated levels of delta-aminolevulinic acid. The severity of the neuropathy and the availability of potential treatments, including avoidance of provocative factors, make identification important.

    Title Myofibrillogenesis Regulator 1 Gene Mutations Cause Paroxysmal Dystonic Choreoathetosis.
    Date August 2004
    Journal Archives of Neurology
    Excerpt

    BACKGROUND: Paroxysmal dystonic choreoathetosis (PDC) is characterized by attacks of involuntary movements that occur spontaneously while at rest and following caffeine or alcohol consumption. Previously, we and others identified a locus for autosomal dominant PDC on chromosome 2q33-2q35. OBJECTIVE: To identify the PDC gene. DESIGN: Analysis of PDC positional candidate genes by exon sequencing and reverse transcription-polymerase chain reaction. SETTING: Outpatient clinical and molecular genetic laboratory at a university hospital.Patients Affected (n = 12) and unaffected (n = 26) subjects from 2 unrelated families with PDC and 105 unrelated control subjects. RESULTS: We identified missense mutations in the myofibrillogenesis regulator gene (MR-1) in affected subjects in 2 unrelated PDC kindreds. These mutations were absent in control subjects and caused substitutions of valine for alanine at amino acid positions 7 and 9. The substitutions disturb interspecies conserved residues and are predicted to alter the MR-1 gene's amino-terminal alpha helix. The MR-1 exon containing these mutations (exon 1) was expressed only in the brain, a finding that explains the brain-specific symptoms of subjects with these mutations. CONCLUSIONS: Although MR-1 gene function is unknown, the precedence of ion channel disturbance in other episodic neurologic disorders suggests that the pathophysiologic features of PDC also involve abnormal ion localization. The discovery that MR-1 mutations underlie PDC provides opportunities to explore this condition's pathophysiologic characteristics and may provide insight into the causes of other paroxysmal neurologic disorders as well as the neurophysiologic mechanisms of alcohol and caffeine, which frequently precipitate PDC attacks.

    Title Hereditary Spastic Paraplegia: Spastin Phenotype and Function.
    Date July 2004
    Journal Archives of Neurology
    Title Advances in the Hereditary Spastic Paraplegias.
    Date January 2004
    Journal Experimental Neurology
    Excerpt

    This review summarizes advances in understanding the genetics of the hereditary spastic paraplegias (HSPs), a diverse group of inherited disorders in which the primary symptom is insidiously progressive difficulty walking due to lower extremity spastic weakness. Twenty HSP loci and nine HSP genes have been discovered. This progress has yielded new insights into the diverse molecular pathogenesis that underlies these clinically similar disorders.

    Title Nipa1 Gene Mutations Cause Autosomal Dominant Hereditary Spastic Paraplegia (spg6).
    Date November 2003
    Journal American Journal of Human Genetics
    Excerpt

    The hereditary spastic paraplegias (HSPs) are genetically heterogeneous disorders characterized by progressive lower-extremity weakness and spasticity. The molecular pathogenesis is poorly understood. We report discovery of a dominant negative mutation in the NIPA1 gene in a kindred with autosomal dominant HSP (ADHSP), linked to chromosome 15q11-q13 (SPG6 locus); and precisely the same mutation in an unrelated kindred with ADHSP that was too small for meaningful linkage analysis. NIPA1 is highly expressed in neuronal tissues and encodes a putative membrane transporter or receptor. Identification of the NIPA1 function and ligand will aid an understanding of axonal neurodegeneration in HSP and may have important therapeutic implications.

    Title Myelopolyneuropathy and Pancytopenia Due to Copper Deficiency and High Zinc Levels of Unknown Origin: Further Support for Existence of a New Zinc Overload Syndrome.
    Date October 2003
    Journal Archives of Neurology
    Excerpt

    OBJECTIVE: To describe a patient with idiopathic zinc overload without an identifiable source and secondary copper deficiency causing myelopolyneuropathy and pancytopenia. DESIGN: Case report. PATIENT AND RESULTS: A 46-year-old man presented with severe bone marrow suppression and subsequently developed progressive myelopathy with sensory ataxia. No identifiable cause of myelopathy was detected, and his neuroimaging findings were unremarkable. Plasma analysis demonstrated a low copper level and an increased zinc level (<10 micro g/dL [<12.6-18.9 micro mol/L] and 184 micro g/dL [28.2 micro mol/L], respectively; normal range for both, 80-120 micro g/dL [12.6-18.9 micro mol/L and 12.3-18.4 micro mol/L, respectively) and a low level of ceruloplasmin. There was no evidence for an external source of zinc. Daily oral supplementation with 2 mg resulted in the prompt reversal of hematologic abnormalities, improved but still subnormal plasma copper levels, and normalization of ceruloplasmin values. The patient's neurologic condition deteriorated further, with worsening of myelopathy and development of polyneuropathy. Analyses of plasma copper and zinc levels demonstrated persisting hyperzincemia and subnormal copper levels during 4 years of follow-up. Increased copper supplementation to 8 mg/d partially reversed his neurologic signs. A clinical investigation of 6 siblings and 1 surviving parent did not identify family members with similar abnormalities. CONCLUSIONS: Persistent hyperzincemia without an identifiable external source appears to be a primary metabolic defect, while copper deficiency is a secondary phenomenon, causing hematologic and neurologic abnormalities. Two unrelated patients with similar idiopathic hyperzincemia and hypocupremia have been recently described. This suggests the existence of a new metabolic disorder with idiopathic zinc overload.

    Title The Second Kindred with Autosomal Dominant Distal Myopathy Linked to Chromosome 14q: Genetic and Clinical Analysis.
    Date October 2003
    Journal Archives of Neurology
    Excerpt

    BACKGROUND: Distal myopathies (MPDs) are genetically heterogeneous. Genetic causes within this subgroup of muscle disorders remain largely unknown. An MPD linked to chromosome 14q11-q13 (MPD1) is rare, and to our knowledge, only one family with definitive linkage has been described. OBJECTIVE: To describe the results of clinical and genetic analysis of the second kindred with MPD1. PATIENTS AND METHODS: We have identified a family with an MPD segregating in an autosomal dominant fashion. We tested linkage to previously identified genetic loci on chromosomes 2p, 2q, and 14q. The coding sequence of PABP2 (the polyadenylate-binding protein 2 gene) was analyzed. RESULTS: Every affected individual had selective weakness of foot extensors, with the average age of symptom onset at 20 years. Some patients also had proximal weakness, but none had signs of finger or hand extensor muscle involvement, even in advanced stages of the disease. Two typically affected individuals had signs of idiopathic dilated cardiomyopathy. Genetic analysis detected a tight linkage to chromosome 14q11-q13. Recombination at the telomeric end of the 14q11-q13 locus was found in an unaffected individual who was not considered to be at risk, potentially reducing the locus interval by 2 centimorgans. No mutations in the PABP2 gene were identified. CONCLUSIONS: To our knowledge, our described family is only the second known kindred with a chromosome 14-linked MPD in whom the linkage has been unequivocally established. We did not detect signs of involvement of hand or finger extensors and neck muscles, seen in the original family with MPD1. The degree and frequency of proximal weakness seem to be more prominent than in other patients with MPD1. Haplotype analysis suggests that the gene is located between polymorphic microsatellite markers D14S283 and D14S1034 on chromosome 14q11-q13. The presence of cardiomyopathy in some affected individuals may help in the identification of candidate genes.

    Title The Hereditary Spastic Paraplegias: Nine Genes and Counting.
    Date September 2003
    Journal Archives of Neurology
    Excerpt

    The hereditary spastic paraplegias (HSPs) are inherited neurologic disorders in which the primary symptom is insidiously progressive difficulty walking due to lower extremity weakness and spasticity. There have been great strides in our knowledge of this group of disabling disorders; 20 HSP loci and 9 HSP genes have been discovered. Insights into the molecular causes of HSPs are beginning to emerge. This review summarizes these advances in HSPs' genetics.

    Title Treatment of Wilson Disease with Ammonium Tetrathiomolybdate: Iii. Initial Therapy in a Total of 55 Neurologically Affected Patients and Follow-up with Zinc Therapy.
    Date April 2003
    Journal Archives of Neurology
    Excerpt

    BACKGROUND: It is unclear what anticopper drug to use for patients with Wilson disease who present with neurologic manifestations because penicillamine often makes them neurologically worse and zinc is slow acting. OBJECTIVE: To evaluate the frequency of neurologic worsening and drug adverse effects with ammonium tetrathiomolybdate. DESIGN: Open-label study of 55 untreated patients (22 of them new) presenting with neurologic Wilson disease treated with tetrathiomolybdate varying from 120 to 410 mg/d for 8 weeks and then followed up for 3 years. Neurologic function was assessed with scored neurologic and speech tests. SETTING: A university hospital referral setting. PATIENTS: All untreated, newly diagnosed patients with neurologic Wilson disease. INTERVENTION: Treatment with tetrathiomolybdate. MAIN OUTCOME MEASURES: Neurologic function was evaluated by neurologic and speech examinations. Drug adverse effects were evaluated by complete blood cell counts and biochemical measures. RESULTS: Only 2 (4%) of 55 patients treated with tetrathiomolybdate showed neurologic deterioration, compared with an estimated 50% of penicillamine-treated patients. Five of the 22 new patients exhibited bone marrow suppression and 3 had aminotransferase elevations. These numbers are higher than in the original 33 patients and appear to be due primarily to a more rapid dose escalation. CONCLUSIONS: Tetrathiomolybdate shows excellent efficacy in patients with Wilson disease who present with neurologic manifestations. With rapid escalation of dose, adverse effects from bone marrow suppression or aminotransferase elevations can occur.

    Title Hereditary Spastic Paraplegia.
    Date January 2003
    Journal Neurologic Clinics
    Excerpt

    The hereditary spastic paraplegias are a large group of clinically similar disorders. Seventeen different HSP loci have been discovered thus far. Different genetic forms of uncomplicated HSP are clinically very similar. Except for the average age at which symptoms appear, different genetic types of uncomplicated HSP cannot be distinguished reliably by clinical parameters alone. For most subjects, HSP is a diagnosis of exclusion. The differential diagnosis includes treatable disorders as well as those for which the prognosis is quite different from HSP. Even with the emerging availability of laboratory testing for HSP gene mutations, it is still essential that alternative disorders be excluded by careful history, examination, laboratory studies, neuroimaging, and neurophysiologic evaluation. Uncomplicated HSP is due to axonal degeneration at the ends of the longest motor (corticospinal tract) and sensory (dorsal column fibers) in the spinal cord. The observation that some forms begin in childhood and are essentially nonprogressive while other forms begin in adulthood and are slowly progressive raises the possibility that some forms of HSP (e.g.; those associated with LICAM gene mutations and possibly those due to SPG3A mutations) are neurodevelopmental disorders; and other forms are truly neurodegenerative disorders. The mechanisms by which spastin, atlastin, and paraplegin mutations cause axonal degeneration that results in clinically similar forms of HSP are not known. Nonetheless, the identification of these genes and the ability to generate animal models of these forms of HSP will permit direct exploration of the molecular basis of HSP.

    Title Diagnosis and Treatment of Wilson's Disease.
    Date September 2002
    Journal Seminars in Neurology
    Excerpt

    Wilson's disease is due to an inherited defect in copper excretion into the bile by the liver. The resulting copper accumulation and copper toxicity results in liver disease, and in some patients, brain damage. Patients present, generally between the ages of 10 and 40 years, with liver disease, neurological disease of a movement disorder type, or behavioral abnormalities, and often with a combination of these. Because Wilson's disease is effectively treated, it is extremely important for physicians to learn to recognize and diagnose the disease. Treatment options have evolved rapidly in the last few years, with zinc now being the drug of choice in most situations.

    Title Hereditary Spastic Paraplegia: Genetic Heterogeneity and Genotype-phenotype Correlation.
    Date September 2002
    Journal Seminars in Neurology
    Excerpt

    Hereditary spastic paraplegia (HSP) is a group of disorders whose primary symptom is insidiously progressive, lower extremity spasticity and weakness. Neuropathological analysis of "pure" HSP reveals axonal degeneration that is maximal in the terminal portions of the longest descending and ascending tracts (crossed and uncrossed corticospinal tracts to the legs and fasciculus gracilis, respectively). HSP may be transmitted as an X-linked, autosomal recessive, or autosomal dominant trait, each of which is genetically heterogeneous: mutations in different genes cause clinically similar disorders. To date, there are at least three genetic loci for X-linked HSP; at least three genetic loci for autosomal recessive HSP; and at least six genetic loci for autosomal dominant HSP. The genetic basis for three of these twelve forms of HSP have been discovered. One form of autosomal recessive HSP (on chromosome 16) is due to mutations in the paraplegin gene, which encodes a mitochondrial protein homologous to metalloproteases. One form of X-linked HSP is caused by mutations in the proteolipoprotein gene, an intrinsic myelin protein. Mutation in this gene also causes the dysmyelinating disorder, Pelizeaus-Merzbacher disease. X-linked spastic paraplegia can be caused also by mutations in the L1CAM gene. This review summarizes our current understanding of genetic heterogeneity and genotype-phenotype correlation in HSP.

    Title Hereditary Spastic Paraplegia: the Pace Quickens.
    Date August 2002
    Journal Annals of Neurology
    Title White Matter Changes in Wilson Disease.
    Date June 2002
    Journal Archives of Neurology
    Title Spastic Paraplegia, Ataxia, Mental Retardation (spar): a Novel Genetic Disorder.
    Date March 2002
    Journal Neurology
    Excerpt

    OBJECTIVE: To describe a kindred with a dominantly inherited neurologic disorder manifested either as uncomplicated spastic paraplegia or ataxia, spastic paraplegia, and mental retardation. METHODS: Neurologic examinations and molecular genetic analysis (exclusion of known SCA and HSP genes and loci; and trinucleotide repeat expansion detection [RED]) were performed in six affected and four unaffected subjects in this family. MRI, electromyography (EMG), and nerve conduction studies were performed in three affected subjects. RESULTS: The phenotype of this dominantly inherited syndrome varied in succeeding generations. Pure spastic paraplegia was present in the earliest generation; subsequent generations had ataxia and mental retardation. MRI showed marked atrophy of the spinal cord in all patients and cerebellar atrophy in those with ataxia. Laboratory analysis showed that the disorder was not caused by mutations in genes that cause SCA-1, SCA-2, SCA-3, SCA-6, SCA-7, SCA-8, and SCA-12; not linked to other known loci for autosomal dominant ataxia (SCA-4, SCA-5, SCA-10, SCA-11, SCA-13, SCA-14, and SCA-16); and not linked to known loci for autosomal dominant hereditary spastic paraplegia (HSP) (SPG-3, SPG-4, SPG-6, SPG-8, SPG-9, SPG-10, SPG-12, and SPG-13) or autosomal recessive HSP SPG-7. Analysis of intergenerational differences in age at onset of symptoms suggests genetic anticipation. Using RED, the authors did not detect expanded CAG, CCT, TGG, or CGT repeats that segregate with the disease. CONCLUSIONS: The authors describe an unusual, dominantly inherited neurologic disorder in which the phenotype (pure spastic paraplegia or spastic ataxia with variable mental retardation) differed in subsequent generations. The molecular explanation for apparent genetic anticipation does not appear to involve trinucleotide repeat expansion.

    Title Hereditary Spastic Paraplegia Linked to Chromosome 14q11-q21: Reduction of the Spg3 Locus Interval from 5.3 to 2.7 Cm.
    Date February 2002
    Journal Journal of Medical Genetics
    Title Novel Mental Retardation-epilepsy Syndrome Linked to Xp21.1-p11.4.
    Date January 2002
    Journal Annals of Neurology
    Excerpt

    We evaluated a kindred with X-linked mental retardation and epilepsy. Seven affected males with mild to moderate mental retardation developed seizures (primarily generalized, tonic-clonic, and atonic) that began on average at 6.8 months of age (range, 4 to 14 months). These patients did not have a history of infantile spasms. There were no dysmorphic features. Other than mental retardation, the neurological examination was unremarkable, with exception of 2 affected subjects who had mild generalized rigidity and ataxia. We identified tight linkage to a group of markers on Xp21.1-p11.4. A maximum two-point LOD score of +3.83 at straight theta = 0 was obtained for markers DXS8090, DXS1069, DXS8102, and DXS8085. This locus spans 7.7cM between DXS1049 and DXS8054 and does not overlap the locus for X-linked West syndrome. The tetraspanin gene, implicated in nonspecific mental retardation, is mapped to this region. We sequenced the tetraspanin coding sequence in subjects with X-linked mental retardation and epilepsy and did not identify disease-specific mutations. The syndrome we describe, designated X-linked mental retardation and epilepsy, is clinically and genetically distinct from X-linked West syndrome and other X-linked mental retardation-epilepsy syndromes.

    Title Progressive Spastic Paraparesis: Hereditary Spastic Paraplegia and Its Relation to Primary and Amyotrophic Lateral Sclerosis.
    Date December 2001
    Journal Seminars in Neurology
    Excerpt

    The syndrome of insidiously progressive spastic weakness of both legs occurs in a number of etiologically distinct disorders including hereditary spastic paraplegia (HSP), primary lateral sclerosis (PLS), and sometimes in amyotrophic lateral sclerosis (ALS). This review summarizes the clinical and pathologic relationship between these disorders.

    Title Mutations in a Newly Identified Gtpase Gene Cause Autosomal Dominant Hereditary Spastic Paraplegia.
    Date December 2001
    Journal Nature Genetics
    Excerpt

    The hereditary spastic paraplegias (HSPs; Strümpell-Lorrain syndrome, MIM number 18260) are a diverse class of disorders characterized by insidiously progressive lower-extremity spastic weakness (reviewed in refs. 1-3). Eight autosomal dominant HSP (ADHSP) loci have been identified, the most frequent of which is that linked to the SPG4 locus on chromosome 2p22 (found in approximately 42%), followed by that linked to the SPG3A locus on chromosome 14q11-q21 (in approximately 9%). Only SPG4 has been identified as a causative gene in ADHSP. Its protein (spastin) is predicted to participate in the assembly or function of nuclear protein complexes. Here we report the identification of mutations in a newly identified GTPase gene, SPG3A, in ADHSP affected individuals.

    Title Acid-sensing Ion Channel (asic) 4 Gene: Physical Mapping, Genomic Organisation, and Evaluation As a Candidate for Paroxysmal Dystonia.
    Date December 2001
    Journal European Journal of Human Genetics : Ejhg
    Excerpt

    Acid-sensing ion channels (ASICs) are protongated Na(+) channels. They have been implicated with synaptic transmission, pain perception as well as mechanoperception. ASIC4 is the most recent member of this gene family. It shows expression throughout the central nervous system with strongest expression in pituitary gland. ASIC4 is inactive by itself and its function is unknown. Mutations in ion channel subunits, which are homologues of ASICs lead to neurodegeneration in Caenorhabditis elegans. It has, therefore, been speculated that similar mutations in ASICs may be responsible for neurodegeneration in humans. Here, we show that ASIC4 maps to the long arm of chromosome 2 in close proximity to the locus for paroxysmal dystonic choreoathetosis (PDC), a movement disorder with unknown cause. Ion channel genes have been shown to cause several other paroxysmal neurologic disorders and are important candidate genes for PDC. We established the genomic organisation of the ASIC4 gene and screened a PDC pedigree for mutations in the coding region. Although we identified three polymorphisms in the Cterminal part of the ASIC4 protein, these were not present in each affected subject in the PDC kindred we analysed. Therefore, although the ASIC4 gene is physically mapped to the PDC locus, our data indicates that ASIC4 gene mutation is not the cause of PDC. It remains to be established if mutations in ASIC4 or other ASIC subunits may cause neurological disorders.

    Title Prenatal Diagnosis of Hereditary Spastic Paraplegia.
    Date July 2001
    Journal Prenatal Diagnosis
    Excerpt

    Hereditary spastic paraplegia (HSP) is a degenerative neurologic disorder that causes progressive, often severe, spastic weakness in the legs. Autosomal dominant HSP is a highly penetrant, genetically heterogeneous disorder with loci present on chromosomes 2p21-24, 2q24-34, 8q23-24, 10q23.3-24, 12q13, 14q12-23, 15q11-14 and 19q13.1. We identified a large HSP kindred in which the disorder was tightly linked to chromosome 14q12-23. We tested chorionic villus DNA samples of two at-risk fetuses for inheritance of microsatellite polymorphisms flanking and within this locus that segregated with the disease in this family. Whereas samples from the first fetus showed inheritance of a haplotype segregating with the disease allele (indicating high risk of developing HSP), samples from the second fetus showed inheritance of a haplotype segregating with the normal allele (indicating low risk of developing HSP). This is the first report of prenatal testing for HSP. Published in 2001 by John Wiley & Sons, Ltd.

    Title Treatment of Wilson's Disease with Zinc Xvi: Treatment During the Pediatric Years.
    Date April 2001
    Journal The Journal of Laboratory and Clinical Medicine
    Excerpt

    The objectives were to evaluate appropriate doses of zinc acetate and its efficacy for the maintenance management of Wilson's disease in pediatric cases. Pediatric patients of 1 to 5 years of age were given 25 mg of zinc twice daily; patients of 6 to 15 years of age, if under 125 pounds body weight, were given 25 mg of zinc three times daily; and patients 16 years of age or older were given 50 mg of zinc three times daily. Patients were followed for efficacy (or over-treatment) until their 19th birthday by measuring levels of urine and plasma copper, urine and plasma zinc and through liver function tests and quantitative speech and neurologic scores. Patients were followed for toxicity by measures of blood counts, blood biochemistries, urinalysis, and clinical follow-up. Thirty-four patients, ranging in ages from 3.2 to 17.7 years of age, were included in the study. All doses met efficacy objectives of copper control, zinc levels, neurologic improvement, and maintenance of liver function except for episodes of poor compliance. No instance of over-treatment was encountered. Four patients exhibited mild and transient gastric disturbance from the zinc. Zinc therapy in pediatric patients appears to have a mildly adverse effect on the high-density lipoprotein/total cholesterol ratio, contrary to results of an earlier large study of primarily adults. In conclusion, zinc is effective and safe for the maintenance management of pediatric cases of Wilson's disease. Our data are strongest in children above 10 years of age. More work needs to be done in very young children, and the cholesterol observations need to be studied further.

    Title Mitochondrial Analysis in Autosomal Dominant Hereditary Spastic Paraplegia.
    Date January 2001
    Journal Neurology
    Title Treatment of Wilson's Disease with Zinc. Xvii: Treatment During Pregnancy.
    Date February 2000
    Journal Hepatology (baltimore, Md.)
    Excerpt

    Therapy of Wilson's disease continues to evolve. In 1997, zinc acetate was added to the list of drugs approved by the Food and Drug Administration, which includes penicillamine and trientine. The mechanism of zinc's anticopper action is unique. It induces intestinal cell metallothionein, which binds copper and prevents its transfer into blood. As intestinal cells die and slough, the contained copper is eliminated in the stool. Thus, zinc prevents the intestinal absorption of copper. It is universally agreed that pregnant Wilson's disease patients should remain on anticopper therapy during pregnancy. There are numerous reports of such patients stopping penicillamine therapy to protect their fetus from teratogenicity, only to undergo serious deterioration and even death from renewed copper toxicity. Penicillamine and trientine have teratogenic effects in animals, and penicillamine has known teratogenic effects in humans. In this report we discuss the results of 26 pregnancies in 19 women who were on zinc therapy throughout their pregnancy. The evidence is good that zinc protects the health of the mother during pregnancy. Fetal outcomes were generally quite good, although one baby had a surgically correctable heart defect and one had microcephaly.

    Title Phenotypic Analysis of Autosomal Dominant Hereditary Spastic Paraplegia Linked to Chromosome 8q.
    Date August 1999
    Journal Neurology
    Excerpt

    OBJECTIVE: To describe clinical, electrophysiologic, neuroimaging, and muscle biopsy features in a hereditary spastic paraplegia (HSP) kindred linked to a new HSP locus on chromosome 8q. BACKGROUND: HSP is a genetically diverse group of disorders characterized by insidiously progressive spastic weakness in the legs. We recently analyzed a Caucasian kindred with autosomal dominant HSP and identified tight linkage to a novel HSP locus on chromosome 8q23-24. METHODS: Clinical analysis, nerve conduction studies, electromyography, somatosensory evoked potentials, MRI of brain and spinal cord, and muscle biopsy for mitochondrial analysis were performed in members of the first HSP kindred linked to chromosome 8q. RESULTS: Fifteen individuals showed insidiously progressive spastic paraparesis beginning between ages 22 and 60 years (average, 37.2 years). Spinal cord MRI in 1 moderately affected subject showed significant atrophy of the thoracic spinal cord as determined by cross-sectional area measurements. Somatosensory evoked potential recording, electromyography, nerve conduction studies, and muscle biopsy, including histochemical and biochemical analysis of mitochondrial function, were normal. CONCLUSIONS: The phenotype in this family is that of typical, but severe, uncomplicated HSP. Other than apparently increased severity, there were no clinical features that distinguished this family from autosomal dominant HSP linked to loci on chromosomes 2p, 14q, and 15q. This clinical similarity between different genetic types of autosomal dominant HSP raises the possibility that genes responsible for these clinically indistinguishable disorders may participate in a common biochemical cascade. Normal results of muscle histochemical and biochemical analysis suggest that mitochondrial disturbance, a feature of chromosome 16-linked autosomal recessive HSP due to paraplegin gene mutations, is not a feature of chromosome 8q-linked autosomal dominant HSP and may not be a common factor of HSP in general.

    Title Report of the Fourth International Workshop on Human Chromosome 15 Mapping 1997.
    Date June 1999
    Journal Cytogenetics and Cell Genetics
    Title (+)-alpha-[11c]dihydrotetrabenazine Pet Imaging in Familial Paroxysmal Dystonic Choreoathetosis.
    Date May 1999
    Journal Neurology
    Excerpt

    Clinical observations suggest a disturbance of striatal dopaminergic function in familial paroxysmal dystonic choreoathetosis (PDC). The authors used PET with [11C]dihydrotetrabenazine (DTBZ) to study striatal dopaminergic innervation in PDC. The results did not reveal abnormal DTBZ binding potential in PDC striatum. This suggests that dopaminergic abnormalities, if present, may be due to altered regulation of dopamine release or to postsynaptic mechanisms, rather than to an altered density of nigrostriatal innervation.

    Title Novel Locus for Autosomal Dominant Hereditary Spastic Paraplegia, on Chromosome 8q.
    Date April 1999
    Journal American Journal of Human Genetics
    Excerpt

    Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous group of disorders characterized by insidiously progressive spastic weakness in the legs. Genetic loci for autosomal dominant HSP exist on chromosomes 2p, 14q, and 15q. These loci are excluded in 45% of autosomal dominant HSP kindreds, indicating the presence of additional loci for autosomal dominant HSP. We analyzed a Caucasian kindred with autosomal dominant HSP and identified tight linkage between the disorder and microsatellite markers on chromosome 8q (maximum two-point LOD score 5.51 at recombination fraction 0). Our results clearly establish the existence of a locus for autosomal dominant HSP on chromosome 8q23-24. Currently this locus spans 6.2 cM between D8S1804 and D8S1774 and includes several potential candidate genes. Identifying this novel HSP locus on chromosome 8q23-24 will facilitate discovery of this HSP gene, improve genetic counseling for families with linkage to this locus, and extend our ability to correlate clinical features with different HSP loci.

    Title Analysis of Microtubule-associated Protein 1a Gene in Hereditary Spastic Paraplegia.
    Date December 1998
    Journal Neurology
    Title Treatment of Wilson's Disease with Zinc: Xv Long-term Follow-up Studies.
    Date November 1998
    Journal The Journal of Laboratory and Clinical Medicine
    Excerpt

    Wilson's disease is an inherited disease of copper accumulation caused by a failure of biliary excretion of excess copper. Accumulated copper causes liver disease in these patients, and in perhaps two thirds of patients, it causes brain damage leading to clinical neurologic or psychiatric dysfunction. Maintenance treatment involves reversing the positive copper balance. The earliest approaches have used chelators, such as penicillamine or trientine, which increase the urinary excretion of copper. A more recent approach has used zinc, which blocks the absorption of copper and increases copper excretion in the stool. Because of the high level of endogenously secreted copper in alimentary secretions, the reabsorption of which is partially blocked by zinc therapy, zinc acts to remove accumulated copper from the body as well as prevent its reaccumulation. In the present article we present data on the long-term follow-up (up to 10 years) of maintenance zinc treatment of 141 patients with Wilson's disease. The data presented document that zinc is effective as a sole therapy in the long-term maintenance treatment of Wilson's disease and that it has a low toxicity. The results demonstrate the efficacy of zinc therapy in treating the presymptomatic patient from the beginning of therapy. We also present limited data on the use of zinc in the treatment of pregnant patients and children who have Wilson's disease; these data also indicate efficacy and low toxicity. The median follow-up period for the group as a whole is 4.8 years; for the presymptomatic patients it is 6.5 years; for the children it is 3.6 years.

    Title Approach to Patients with Inherited Neurologic Disorders.
    Date August 1998
    Journal Seminars in Neurology
    Excerpt

    There have been tremendous advances in our understanding of inherited neurologic disorders. It is important to recognize that genetic factors contribute to common neurologic disorders once considered idiopathic. Diagnosing and counseling individuals with inherited neurologic disorders requires understanding of fundamental genetic principles. The essential approach to such patients and their family members is presented.

    Title Advances in Hereditary Spastic Paraplegia.
    Date October 1997
    Journal Current Opinion in Neurology
    Excerpt

    Hereditary spastic paraplegia refers to a group of clinically similar disorders whose primary feature is insidiously progressive lower extremity weakness and spasticity. Hereditary spastic paraplegia is genetically diverse: loci for autosomal recessive (chromosome 8p), autosomal dominant (chromosome 2p, 14q, and 15q), and x-linked hereditary spastic paraplegia have been identified. The existence of hereditary spastic paraplegia families for whom the disorder is unlinked to these loci indicates the existence of additional, as yet undiscovered, hereditary spastic paraplegia loci. Hereditary spastic paraplegia exhibits axonal degeneration that is maximal at the terminal portions of the longest central nervous system axons. Efforts to positionally clone the hereditary spastic paraplegia gene are in progress.

    Title Paroxysmal Dystonic Choreoathetosis Linked to Chromosome 2q: Clinical Analysis and Proposed Pathophysiology.
    Date September 1997
    Journal Neurology
    Excerpt

    We describe clinical features of a large Polish-American kindred in which autosomal-dominant, paroxysmal dystonic choreoathetosis (PDC) was linked to a locus on chromosome 2q. Episodes of generalized dystonia and choreoathetosis involving the face and all extremities began in early childhood, lasted for 30 minutes to several hours, and occurred up to several times each week. There was no interruption of consciousness and EEGs were normal during the episodes. Paroxysmal dyskinesia occurred at rest both spontaneously and following caffeine or alcohol consumption. Neurologic examinations were normal between attacks. The cause of PDC is unknown. We deduced a model of PDC pathophysiology from analyzing neurophysiologic effects of alcohol and caffeine (which provoke attacks of PDC), the variably beneficial effects of levodopa-carbidopa, and the occurrence of dystonia and paroxysmal dyskinesia in biopterin synthesis disorders. We propose that nigrostriatal neurons in PDC patients have either marginally deficient dopamine synthesis or excessive alcohol- and caffeine-induced dopamine release; and that following alcohol- and caffeine-induced dopamine release, PDC patients experience a period of dopamine deficiency.

    Title Apolipoprotein E and Alzheimer's Disease: Strength of Association is Related to Age at Onset.
    Date January 1997
    Journal Dementia (basel, Switzerland)
    Excerpt

    Apolipoprotein E (apoE) epsilon 4 allele frequency among Alzheimer's disease (AD) patients is increased compared to control subjects and is influenced by the presence of other genetic factors and age at symptom onset. We examined the relationship between age at AD symptom onset and apoE by comparing the apoE epsilon 4 allele frequency of normal, elderly control subjects (n = 107) to that in AD patients (n = 123), divided into four age-at-onset periods. Additionally, the distribution of symptom onset ages of AD patients with and without apoE epsilon 4 alleles was determined. We observed increased apoE epsilon 4 allele frequencies between the AD onset ages of 55 and 75 years, but not at the extremes of onset ages (i.e. onset between 45 and 54 years of age and after age 75). Our data suggests that having an apoE epsilon 4 allele increases the likelihood that AD patients will develop symptoms in the middle range of onset ages. At the extremes of AD onset ages, non-apoE factors, including other genetic factors and age, are more important determinants of risk of developing AD.

    Title Human Microtubule-associated Protein 1a (map1a) Gene: Genomic Organization, Cdna Sequence, and Developmental- and Tissue-specific Expression.
    Date December 1996
    Journal Genomics
    Excerpt

    Microtubule-associated proteins (MAPs) regulate microtubule stability and play critical roles in neuronal development and the balance between neuronal plasticity and rigidity. MAP1a (HGMW-approved symbol MAP1A) stabilizes microtubules in postnatal axons. We describe human MAP1a's genomic organization and deduced cDNA and amino acid sequences. MAP1a is a single-copy gene spanning 10.5 kb. MAP1a coding sequence is contained in five exons. Translation begins in exon 3. Human MAP1a contains 2805 amino acids (predicted molecular weight 306.5 kDa) and is slightly larger than rat MAP1a (2774 amino acids). Like rat and bovine MAP1a, human MAP1a contains conserved tubulin binding motifs in the amino-terminal region. The carboxy-terminal portion contains a conserved pentadecapeptide that is present in the light chain portion of rat and bovine MAP1a/LC2 polyprotein. We show that human MAP1a gene expression occurs almost exclusively in the brain and that there is approximately 10-fold greater gene expression in adult brain compared to fetal brain. Strong, interspecies conservation between human and rat MAP1a cDNA and amino acid sequences indicates important relationships between MAP1a's function and its primary amino acid sequence.

    Title Treatment of Wilson Disease with Ammonium Tetrathiomolybdate. Ii. Initial Therapy in 33 Neurologically Affected Patients and Follow-up with Zinc Therapy.
    Date November 1996
    Journal Archives of Neurology
    Excerpt

    OBJECTIVE: To test the efficacy and toxic effects of ammonium tetrathiomolybdate in the initial treatment of a relatively large series of patients with neurologic symptoms and signs caused by Wilson disease. Two key aspects of efficacy are to preserve the neurologic function present at the onset of therapy and to maximize the opportunity for long-term recovery. DESIGN: An open study of 33 patients treated for 8 weeks each, including further follow-up data on the original 17 patients. Neurologic function was evaluated by frequent quantitative neurologic and speech pathology examinations. Several copper-related variables were studied to evaluate the effect of the drug on copper, and several biochemical and clinical variables were studied to evaluate potential toxic effects. Patients were then followed up at yearly intervals, with follow-up periods of 1 to 8 years reported. SETTING: A university hospital referral setting. INTERVENTION: Patients were generally treated for 8 weeks with tetrathiomolybdate, followed by zinc maintenance therapy. MAIN OUTCOME MEASURES: Neurologic function was evaluated by quantitative neurologic and motor speech examinations and magnetic resonance imaging scans of the brain. RESULTS: During the 8 weeks of tetrathiomolybdate administration, only 1 of the 33 patients showed deterioration in neurologic function. Copper status and potential further toxic effects were generally well controlled quickly. Evaluation of data from individual patients revealed evidence of a toxic side effect in only 1 patient, who exhibited reversible anemia. During the ensuing period of follow-up of 1 to 6 years, neurologic recovery in most patients was good to excellent. CONCLUSIONS: Tetrathiomolybdate appears to be an excellent form of initial treatment in patients with Wilson disease who present with neurologic symptoms and signs. In contrast to penicillamine therapy, initial treatment with tetrathiomolybdate rarely allows further, often irreversible, neurologic deterioration.

    Title Paroxysmal Dystonic Choreoathetosis: Tight Linkage to Chromosome 2q.
    Date July 1996
    Journal American Journal of Human Genetics
    Excerpt

    Paroxysmal dystonic choreoathetosis (PDC) is characterized by attacks of involuntary movements that last up to several hours and occur at rest both spontaneously and following caffeine or alcohol consumption. We analyzed a Polish-American kindred with autosomal dominant PDC and identified tight linkage between the disorder and microsatellite markers on chromosome 2q (maximum two-point LOD score 4.77; recombination fraction 0). Our results clearly establish the existence of a locus for autosomal dominant PDC on distal chromosome 2q. The fact that three other paroxysmal neurological disorders (periodic ataxia with myokymia and hypo- and hyperkalemic periodic paralysis) are due to mutation in ion-channel genes raises the possibility that PDC is also due to an ion-channel gene mutation. It is noteworthy that a cluster of sodium-channel genes is located on distal chromosome 2q, near the PDC locus. Identifying the PDC locus on chromosome 2q will facilitate discovery of the PDC gene and enable investigators to determine whether PDC is genetically homogeneous and whether other paroxysmal movement disorders are also genetically linked to the PDC locus.

    Title Hereditary Spastic Paraplegia: Advances in Genetic Research. Hereditary Spastic Paraplegia Working Group.
    Date July 1996
    Journal Neurology
    Excerpt

    Hereditary spastic paraplegia (HSP) is a diverse group of inherited disorders characterized by progressive lower-extremity spasticity and weakness. Insight into the genetic basis of these disorders is expanding rapidly. Uncomplicated autosomal dominant, autosomal recessive, and X-linked HSP are genetically heterogeneous: different genes cause clinically indistinguishable disorders. A locus for autosomal recessive HSP is on chromosome 8q. Loci for autosomal dominant HSP have been identified on chromosomes 2p, 14q, and 15q. One locus (Xq22) has been identified for X-linked, uncomplicated HSP and shown to be due to a proteolipoprotein gene mutation in one family. The existence of HSP families for whom these loci are excluded indicates the existence of additional, as yet unidentified HSP loci. There is marked clinical similarity among HSP families linked to each of these loci, suggesting that gene products from HSP loci may participate in a common biochemical cascade, which, if disturbed, results in axonal degeneration that is maximal at the ends of the longest CNS axons. Identifying the single gene defects that cause HSPs distal axonopathy may provide insight into factors responsible for development and maintenance of axonal integrity. We review clinical, genetic, and pathologic features of HSP and present differential diagnosis and diagnostic criteria of this important group of disorders. We discuss polymorphic microsatellite markers useful for genetic linkage analysis and genetic counseling in HSP.

    Title Late-onset Generalized Disorder of Peroxisomes.
    Date June 1996
    Journal Neurology
    Excerpt

    We diagnosed a unique peroxisomal disorder in a 32-year-old man with profound mental retardation, mild facial dysmorphism, retinal pigmentary degeneration, seizures, and sensorineural deafness. Although plasma very-long-chain fatty acid profile suggested X-linked adrenoleukodystrophy, marked reduction in fibroblast lignoceric acid oxidation and the presence of cytosolic catalase were consistent with Zellweger syndrome (ZS). Unlike ZS, functional peroxisomes were present as indicated by the density of peroxisomes (1.175 gm/ml) similar to peroxisomes from control cells and by partial deficiencies of fibroblast phytanic acid oxidation and dihydroxyacetone phosphate acyltransferase activity. These findings indicate that this patient has a previously undescribed group 3 peroxisomal disorder (multiple peroxisomal enzyme deficiencies with preserved peroxisomes).

    Title Hereditary Spastic Paraplegia Linked to Chromosome 15q: Analysis of Candidate Genes.
    Date June 1996
    Journal Neurology
    Excerpt

    We previously reported an extended kindred with autosomal dominant uncomplicated hereditary spastic paraplegia (HSP) and found close linkage between the disorder and microsatellite polymorphisms on chromosome 15q. Multipoint linkage analysis reached a maximum LOD score (10.16) between D15S128 and D15S156, a region that includes genes encoding alpha5 and beta3 subunits of GABAA receptor. Theoretically, abnormal GABA-mediated neurotransmission could produce spasticity and possibly other changes of HSP. We used genetic linkage analysis to evaluate these two HSP candidate genes and observed obligate recombinants for polymorphisms immediately adjacent to (or within untranslated regions of) genes encoding alpha5 and beta3 GABAA receptor subunits. Although these genes are linked tightly to the HSP locus, our findings conclusively exclude these genes from being responsible for HSP in this kindred.

    Title Autosomal Dominant, Familial Spastic Paraplegia, Type I: Clinical and Genetic Analysis of a Large North American Family.
    Date March 1995
    Journal Neurology
    Excerpt

    "Familial spastic paraplegia" (FSP) refers to clinically and genetically diverse syndromes characterized by insidiously progressive lower extremity spasticity. We evaluated 126 members of a large kindred, including 31 affected subjects, in which FSP was transmitted as a stereotyped, autosomal dominant disorder that showed complete genetic penetrance. Affected subjects developed insidiously progressive gait disturbance between ages 12 and thirty-five. Neurologic examination revealed hyperreflexia and spasticity in the lower extremities, weakness of hip flexion and ankle dorsiflexion, extensor plantar response, diminished vibratory sense in the feet, and pes cavus. Using genetic linkage analysis, we excluded the FSP1 locus on chromosome 14q11.2 as the disease locus in this family. We present the clinical and genetic features of FSP type I, including the age-adjusted risk of developing the disorder in this family.

    Title Autosomal Dominant Familial Spastic Paraplegia: Tight Linkage to Chromosome 15q.
    Date February 1995
    Journal American Journal of Human Genetics
    Excerpt

    Autosomal dominant, uncomplicated familial spastic paraplegia (FSP) is a genetically heterogeneous disorder characterized by insidiously progressive lower-extremity spasticity. Recently, a locus on chromosome 14q was shown to be tightly linked with the disorder in one of three families. We performed linkage analysis in a kindred with autosomal dominant uncomplicated FSP. After excluding the chromosome 14q locus, we observed tight linkage of the disorder to a group of markers on chromosome 15q (maximum two-point lod score 9.70; theta = .05). Our results clearly establish the existence of a locus for autosomal dominant FSP in the centromeric region of chromosome 15q. Comparing clinical and genetic features in FSP families linked to chromosome 14q with those linked to chromosome 15q may provide insight into the pathophysiology of this disorder.

    Title Detecting Prion Protein Gene Mutations by Denaturing Gradient Gel Electrophoresis.
    Date December 1994
    Journal Human Mutation
    Excerpt

    Mutations of the prion protein (PrP) gene are present in patients with Gerstmann-Sträussler-Scheinker syndrome (GSS), familial Creutzfeldt-Jakob disease (CJD), and fatal familial insomnia (FFI). We developed a denaturing gradient gel electrophoresis (DGGE) strategy that readily identifies point mutations in the PrP coding sequence. By comparison with appropriate controls, haplotypes often may be deduced. This method permits samples from many patients with GSS, CJD, as well as patients with unusual degenerative neurologic disorders, to be screened rapidly, sensitively, and inexpensively for the presence of known and novel PrP mutations. We illustrate the sensitivity of this approach by reporting 2 novel polymorphisms in the PrP coding sequence.

    Title Treatment of Wilson's Disease with Ammonium Tetrathiomolybdate. I. Initial Therapy in 17 Neurologically Affected Patients.
    Date June 1994
    Journal Archives of Neurology
    Excerpt

    OBJECTIVE: To test the efficacy and toxicity of a new drug, ammonium tetrathiomolybdate, in the initial treatment of a relatively large series of patients presenting with neurologic signs and symptoms caused by Wilson's disease. The key aspect of efficacy was to preserve the neurologic function present at the onset of therapy. DESIGN: An open study of 17 patients treated for 8 weeks each. Neurologic function was evaluated by frequent quantitative neurologic and speech examinations. Several copper-related variables were studied to evaluate the effect of the drug on copper, and a large number of biochemical and clinical variables were studied to evaluate potential toxicity. Patients were then followed up at yearly intervals, with follow-up periods of 1 to 5 years reported. SETTING: A university hospital referral setting INTERVENTION: Patients were generally treated for 8 weeks with tetrathiomolybdate, followed by zinc maintenance therapy. MAIN OUTCOME MEASURES: Neurologic function was evaluated by quantitative neurologic and speech examinations. RESULTS: None of the patients suffered a loss of neurologic function. Copper status and potential further toxic effects were generally well controlled quickly. No toxic effects resulted from administration of tetrathiomolybdate. During the ensuing period of follow-up of 1 to 5 years, neurologic recovery in most patients was good to excellent. CONCLUSIONS: Tetrathiomolybdate appears to be an excellent form of initial treatment in patients with Wilson's disease presenting with neurologic signs and symptoms. In contrast to penicillamine therapy, initial treatment with tetrathiomolybdate does not result in further, often irreversible neurologic deterioration.

    Title Novel Polymorphism in the A4 Region of the Amyloid Precursor Protein Gene in a Patient Without Alzheimer's Disease.
    Date June 1994
    Journal Neurology
    Excerpt

    We found a novel polymorphism in the amyloid precursor protein (APP) gene in a patient with ischemic cerebrovascular disease who had no evidence of Alzheimer's disease (AD). This polymorphism deletes a Fok I restriction enzyme site and causes the substitution of threonine for alanine at codon 673. This is adjacent to the site at which APP is thought to undergo cleavage in AD. Analysis of this polymorphism may provide insight into the basis of APP processing.

    Title Novel Amyloid Precursor Protein Gene Mutation (codon 665asp) in a Patient with Late-onset Alzheimer's Disease.
    Date May 1994
    Journal Annals of Neurology
    Excerpt

    Amyloid plaques in Alzheimer's disease contain beta-amyloid, encoded by portions of exons 16 and 17 of the amyloid precursor protein. The specific association of rare amyloid precursor protein mutations with some kindreds with early-onset familial Alzheimer's disease suggests that specific abnormalities in amyloid precursor protein may contribute to the pathogenesis of Alzheimer's disease. Until now, there has been no evidence suggesting that amyloid precursor protein mutations could be involved in late-onset or sporadic Alzheimer's disease. We used reverse transcription-polymerase chain reaction, denaturing gradient gel electrophoresis, and direct DNA sequencing to analyze amyloid precursor protein exons 16 and 17 from postmortem cerebellar samples from patients with histologically confirmed Alzheimer's disease and control subjects. We found a novel point mutation, substitution of cytosine for guanine, at nucleotide 2119 (amyloid precursor protein 770 messenger RNA transcript) in a patient with late-onset Alzheimer's disease. This substitution deletes a BglII site and substitutes aspartate for glutamine at codon 665. Denaturing gradient gel electrophoresis analysis showed that this mutation was absent in 40 control subjects and 127 dementia patients. Whether this mutation is a rare but normal variant or contributes to the development of Alzheimer's disease is not known. The BglII restriction fragment length polymorphism enables investigators to determine the frequency of this polymorphism in normal subjects and Alzheimer's disease patients.

    Title Apoe Epsilon 4 Allelic Association with Alzheimer's Disease: Independent Confirmation Using Denaturing Gradient Gel Electrophoresis.
    Date March 1994
    Journal Neurology
    Excerpt

    There is intriguing evidence associating apolipoprotein E (ApoE) with Alzheimer's disease (AD). ApoE is deposited with beta-amyloid in senile plaques and binds to beta-amyloid in vitro. We used denaturing gradient gel electrophoresis to identify ApoE epsilon 2, epsilon 3, and epsilon 4 alleles in 135 control subjects and 57 AD patients. We observed a marked increase in ApoE epsilon 4 allele frequency (0.40) in AD patients compared with control subjects (0.14) (p < 0.0001). Our independent finding of a marked association of ApoE epsilon 4 allele with AD further supports a possible role of ApoE in the pathogenesis of AD and confirms the study of Saunders et al (Neurology 1993;43:1467-1472).

    Title An Mspi Polymorphism in the Hyman Serotonin Receptor Gene (htr2): Detection by Dgge and Rflp Analysis.
    Date June 1993
    Journal Human Molecular Genetics
    Title An Rsai Polymorphism in the Human Serotonin Receptor Gene (htr1a): Detection by Dgge and Rflp Analysis.
    Date June 1993
    Journal Human Molecular Genetics
    Title Ophthalmologic Manifestations of Type B Niemann-pick Diseases.
    Date February 1993
    Journal Metabolic, Pediatric, and Systemic Ophthalmology (new York, N.y. : 1985)
    Excerpt

    Type B Niemann-Pick Disease (NPB) is a rare lysosomal storage disease resulting from diminished activity or deficiency of sphingomyelinase and is characterized by multi-system involvement with visceromegaly. Rare ocular involvement (the Macula Halo Syndrome) has been reported. Eight patients (ages 4-36) with NPB underwent complete ophthalmologic evaluations. All patients had periorbital fullness, a hitherto unreported clinical feature. Two patients had a classic Macula Halo Syndrome. One patient developed peri-macular granular deposits forming an incomplete Macula Halo over 5 years. Another patient had macular granular deposits and developed deterioration of central vision and abnormal visual evoked potentials. Ophthalmologic involvement in NPB is more common than previously described. Complete ophthalmologic evaluation is recommended in all patients suspected to have NPB.

    Title Clinical and Genetic Analysis of Progressive Dystonia with Diurnal Variation.
    Date November 1991
    Journal Archives of Neurology
    Excerpt

    We examined 17 patients with progressive dystonia with diurnal variation, a dominantly inherited, generalized dystonia that begins in childhood. Dystonia was typically least severe in the morning, increased as the day continued, and markedly improved with low doses of carbidopa-levodopa. We also studied the patient's parents, children, and siblings from seven families. We observed a spectrum of neurologic involvement, phenotypic variability among siblings, and incomplete genetic penetrance. Progression of motor impairment over several years, which reaches a plateau during late adolescence, is useful in distinguishing progressive dystonia with diurnal variation from cerebral palsy and degenerative disorders. It is important to recognize the subtle, as well the extreme, manifestations of progressive dystonia with diurnal variation because it is treatable. Genetic counseling must consider that mildly affected parents with little or no disability may have profoundly affected children. Appreciation of the phenotypic variability and degree of genetic penetrance will permit detailed genetic and biochemical analyses.

    Title Allele-specific Sequencing Confirms Novel Prion Gene Polymorphism in Creutzfeldt-jakob Disease.
    Date November 1991
    Journal Neurology
    Excerpt

    We analyzed the prion protein coding sequence in a familial Creutzfeldt-Jakob disease patient who did not have any of the currently recognized prion protein mutations. Denaturing gradient gel electrophoresis indicated that the prion protein coding sequence was heterozygous at least one location. We isolated each allele by denaturing gradient gel electrophoresis and directly sequenced. We found a DNA polymorphism at codon 178 that predicted the amino acid substitution, aspartate----asparagine. Whether this represents a benign polymorphism or pathogenic mutation will depend on analysis of the functional consequences of this change. Denaturing gradient gel electrophoresis and allele-specific sequencing proved to be efficient means of analyzing sequence polymorphisms in this gene.

    Title Expression of Human Glucocerebrosidase in Long-term Reconstituted Mice Following Retroviral-mediated Gene Transfer into Hematopoietic Stem Cells.
    Date May 1991
    Journal Human Gene Therapy
    Excerpt

    A retroviral vector (GTN) in which the glucocerebrosidase (GCase) cDNA is driven by the Moloney murine leukemia virus (Mo-MuLV) long terminal repeat (LTR) was tested for transfer efficiency and expression of the GCase gene in long-term reconstituted mice. Eleven W/Wv mice were transplanted with unselected GTN-infected bone marrow cells and 10 of these mice were analyzed 3 months later. Seven of these 10 mice (70%) contained the intact proviral genome in bone marrow, spleen, and thymus. Of these 7,3 mice contained a high-copy number of the provirus in all the hematopoietic tissues tested. The mice contained anywhere from one to four proviral integration sites that were the same in all three tissues, indicating that these mice have been repopulated by one or more transduced multipotential hematopoietic stem cells. Five months after transplantation, bone marrow from the eleventh mouse was transplanted into secondary recipient animals. The secondary recipients contained the intact proviral genome in the bone marrow, spleen, thymus, and macrophages 4 months after the secondary transplantation. This further supports the conclusion that hematopoietic stem cells have indeed been targeted. Human GCase RNA was detected in all 7 mice containing the proviral DNA. These results demonstrate expression of the human GCase gene in the progeny of repopulating hematopoietic stem cells of mice following gene transfer.

    Title Hyperlipidemia As a Complication of Niemann-pick Type B Disease.
    Date February 1991
    Journal Clinical Pediatrics
    Title Correction of Glucocerebrosidase Deficiency After Retroviral-mediated Gene Transfer into Hematopoietic Progenitor Cells from Patients with Gaucher Disease.
    Date April 1990
    Journal Proceedings of the National Academy of Sciences of the United States of America
    Excerpt

    Retroviral gene transfer has been used successfully to correct the glucocerebrosidase (GCase) deficiency in primary hematopoietic cells from patients with Gaucher disease. For this model of somatic gene therapy, we developed a high-titer, amphotropic retroviral vector designated NTG in which the human GCase gene was driven by the mutant polyoma virus enhancer/herpesvirus thymidine kinase gene (tk) promoter (Py+/Htk). NTG normalized GCase activity in transduced Gaucher fibroblasts and efficiently infected human monocytic and erythroleukemic cell lines. RNA blot-hybridization (Northern blot) analysis of these hematopoietic cell lines showed unexpectedly high-level expression from the Moloney murine leukemia virus long terminal repeat (Mo-MLV LTR) and levels of Py+/Htk enhancer/promoter-initiated human GCase RNA that approximated endogenous GCase RNA levels. Furthermore, NTG efficiently infected human hematopoietic progenitor cells. Detection (by means of the polymerase chain reaction) of the provirus in approximately one-third of NTG-infected progenitor colonies that had not been selected in G418-containing medium indicates that relative resistance to G418 underestimated the actual gene transfer efficiency. Northern blot analysis of NTG-infected, progenitor-derived cells showed expression from both the Mo-MLV LTR and the Py+/Htk enhancer/promoter. NTG-transduced hematopoietic progenitor cells from patients with Gaucher disease generated progeny in which GCase activity had been normalized.

    Title Production of Human Glucocerebrosidase in Mice After Retroviral Gene Transfer into Multipotential Hematopoietic Progenitor Cells.
    Date December 1989
    Journal Proceedings of the National Academy of Sciences of the United States of America
    Excerpt

    The human glucocerebrosidase (GC) gene has been transferred efficiently into spleen colony-forming unit (CFU-S) multipotential hematopoietic progenitor cells, and production of human GC RNA and protein has been achieved in transduced CFU-S colonies. High-titer retroviral vectors containing the human GC cDNA were constructed. Mouse bone marrow cells were stimulated with hematopoietic growth factors, infected by coculture with producer cells, and injected into lethally irradiated animals. Four vectors were compared with respect to gene-transfer efficiency into CFU-S progenitors. One vector (G vector) required high concentrations of interleukins 3 and 6 during stimulation and coculture for efficient transduction of CFU-S progenitors. The remaining three vectors (NTG, GTN, and GI vectors) transduced these progenitors at infection frequencies approaching 100% using low concentrations of hematopoietic growth factors to stimulate cell division prior to and during the infection. Vectors using the viral long terminal repeat enhancer/promoter to drive the human GC cDNA produced high levels of human GC RNA in the progeny of CFU-S progenitors after gene transfer. When an internal herpes simplex thymidine kinase promoter assisted by a mutant polyoma enhancer was used to drive the human GC cDNA (NTG vector), little or no human GC RNA was detected in transduced CFU-S colonies. All three vectors producing human GC RNA in CFU-S colonies can generate human GC as detected by immunochemical analysis of CFU-S colonies. NTG vector-infected bone marrow cells were transplanted into W/Wv recipients to generate long-term reconstituted mice. The capacity of the viral long terminal repeat and the internal thymidine kinase promoter to direct synthesis of RNA in transduced bone marrow and spleen cells 5 months after bone marrow transplantation reflected the performance of these promoters in NTG-transduced CFU-S colonies.

    Title Tetrahydrobiopterin Administration in Biopterin-deficient Progressive Dystonia with Diurnal Variation.
    Date November 1989
    Journal Neurology
    Excerpt

    We administered tetrahydrobiopterin (BH4) to 4 patients with progressive dystonia with diurnal variation (PDDV). One patient improved clinically. Deficient CSF concentrations of HVA and 5-HIAA were unchanged despite marked elevation of CSF biopterin concentration. Variable effectiveness of BH4 in PDDV may reflect reduced number or function of biopterin-metabolizing neurons or variable entry of BH4 into these neurons.

    Title Richter's Transformation of Lymphoma Complicating Gaucher's Disease.
    Date October 1989
    Journal Hematologic Pathology
    Excerpt

    A case of lymphoma in a middle-aged woman with Gaucher's disease, a mu-kappa monoclonal gammopathy, peripheral lymphocytosis, and massive splenomegaly is described. There was no evidence of Gaucher's disease in the splenectomy specimen. Instead, the splenic architecture was effaced by a small lymphocytic lymphoma (SLL), with a few foci of large cell lymphoma (LCL). Immunoperoxidase studies showed that both lymphomatous components had a mu-kappa immunophenotype. Flow cytometric analysis of peripheral blood and spleen lymphocyte surface markers confirmed monoclonality. The intensity of surface immunoglobulin expression and the results of other cell marker studies in the SLL component were consistent with a stage of differentiation beyond that typical of chronic lymphocytic leukemia (CLL). The presence of abundant cytoplasmic immunoglobulin in the SLL and the association with monoclonal gammopathy were more consistent with Waldenström's macroglobulinemia or plasmacytoid lymphocytic lymphoma. The immunohistochemical and flow cytometric findings suggest that the SLL component evolved clonally or underwent Richter's transformation to LCL. Although Gaucher's disease has been associated with a variety of B-cell disorders, the subsequent transformation to a high-grade lymphoma has not been previously reported.

    Title Clinical Spectrum of Niemann-pick Disease Type C.
    Date September 1989
    Journal Neurology
    Excerpt

    Analysis of the neurologic symptomatology in 22 patients with Niemann-Pick disease type C revealed 3 phenotypes: (1) an early-onset, rapidly progressive form associated with severe hepatic dysfunction and psychomotor delay during infancy and later with supranuclear vertical gaze paresis, ataxia, marked spasticity, and dementia; (2) a delayed-onset, slowly progressive form heralded by the appearance, usually in early childhood, of mild intellectual impairment, supranuclear vertical gaze paresis, and ataxia, and later associated with dementia and, variably, seizures and extrapyramidal deficits; (3) a late-onset slowly progressive form distinguished from the 2nd pattern by later age of onset (adolescence or adulthood) and a much slower rate of progression. The existence of the 1st and 2nd phenotypes within the same sibship suggests that they are variant expressions of the same clinicopathologic disorder. Niemann-Pick disease type C should be considered not only in infants and children who present with organomegaly and a progressive neurodegenerative course, but also in adolescents and adults who have insidiously progressive neurologic dysfunction and only slight organomegaly. Associated with the disease is a marked deficiency in the ability of cultured fibroblasts to esterify exogenously supplied cholesterol. Assay of this deficiency is particularly useful for confirming the diagnosis in patients with atypical presentation.

    Title Neurologic Complications in Long-standing Nephropathic Cystinosis.
    Date June 1989
    Journal Archives of Neurology
    Excerpt

    The central nervous system has been considered to be uninvolved in nephropathic cystinosis. Survival into adulthood, following renal dialysis and transplantation, has brought attention to the sequelae of long-standing cystinosis. We examined 14 patients with cystinosis, 12 of whom had undergone renal transplantation. Two patients had neurologic symptoms. One patient had progressive bradykinesia, dementia, and spasticity with computed tomographic scan evidence of cerebral atrophy and multifocal mineralization in bilateral internal capsules and periventricular white matter. One patient had behavioral and, to a lesser extent, cognitive disturbance and computed tomographic scan evidence of marked, progressive cerebral atrophy. Although the remaining patients had normal results of neurologic examinations, 11 had roentgenographic evidence of generalized cerebral atrophy; 2 of these had abnormal electroencephalograms, 1 had borderline-deficient intellectual function, and 2 had computed tomographic scan evidence of multifocal, intracerebral mineralization. The patients with nervous system abnormalities were not distinguished by patterns of medication use, demographic or laboratory features, or the relative severity of cystinosis. Although the neurologic involvement in these patients suggests that cystinosis may eventually involve the central nervous system, the differential diagnosis must include other complications from renal failure, dialysis, and immunosuppression.

    Title Carbamazepine in Fabry's Disease: Effective Analgesia with Dose-dependent Exacerbation of Autonomic Dysfunction.
    Date May 1989
    Journal Neurology
    Excerpt

    Seven patients with Fabry's disease and severe pain received carbamazepine (CMZ). Five of 7 patients had moderate to complete relief based upon self-assessment of pain levels. Preexisting autonomic dysfunction was exacerbated by CMZ in 2. Complications encountered were ileus, urinary retention, and gastrointestinal disturbance. Although CMZ was useful in treatment of pain, caution should be employed in this disease.

    Title Multiple Sulfatase Deficiency.
    Date August 1988
    Journal Neurology
    Excerpt

    Multiple sulfatase deficiency is an inherited disorder characterized by a deficiency of several sulfatases and the accumulation of sulfatides, glycosaminoglycans, sphingolipids, and steroid sulfates in tissues and body fluids. The clinical manifestations represent the summation of two diseases: late infantile metachromatic leukodystrophy and mucopolysaccharidosis. We present a 9-year-old girl with a phenotype similar to a mucopolysaccharidosis: short stature, microcephaly, and mild facial dysmorphism, along with dysphagia, retinal degeneration, developmental arrest, and ataxia. We discuss the importance of measuring the sulfatase activities in the leukocytes, and the instability of sulfatases in the cultured skin fibroblasts.

    Title Treatable Dystonia Presenting As Spastic Cerebral Palsy.
    Date July 1988
    Journal Pediatrics
    Title Dystonia with Marked Diurnal Variation Associated with Biopterin Deficiency.
    Date June 1988
    Journal Neurology
    Excerpt

    Two pairs of siblings with severe dystonia with marked diurnal fluctuation had both reduced CSF concentration of biopterin and marked symptomatic improvement of the dystonia in response to levodopa. Whether the reduced concentration of biopterin reflects focal abiotrophy of biopterin-containing neurons or deficiency of biopterin synthesis is uncertain. A fifth individual, who had a systemic deficiency of biopterin synthesis, shared the features of reduced biopterin in CSF, marked diurnal variation in the degree of dystonia, and clinical improvement in response to levodopa. Generalized dystonia with marked diurnal fluctuation was therefore shared by the four patients in whom biopterin deficiency was limited to the CNS and the patient with systemic deficiency of biopterin.

    Title Type C Niemann-pick Disease. Abnormal Metabolism of Low Density Lipoprotein in Homozygous and Heterozygous Fibroblasts.
    Date January 1987
    Journal The Journal of Biological Chemistry
    Excerpt

    The esterification of cholesterol derived from human low density lipoprotein (LDL) or fetal bovine serum (FBS) was deficient in cultured fibroblasts from subjects with heterozygous and homozygous type C Niemann-Pick (NPC) disease. Failure to significantly esterify LDL-derived cholesterol resulted in abnormal accumulation of predominantly unesterified cholesterol in homozygous NPC fibroblasts. Compared with normal and homozygous fibroblasts, heterozygous NPC fibroblasts synthesized intermediate levels of cholesteryl ester during the initial 6 h of incubation with LDL. The rate of cholesterol esterification in heterozygous cells was normal when measured over a 24-h period of incubation with LDL. In addition to demonstrating a defect in cholesterol esterification, homozygous NPC fibroblasts accumulated more total cholesterol when incubated with LDL or FBS than normal fibroblasts accumulated. When heterozygous NPC fibroblasts were incubated with LDL or FBS, cellular accumulation of cholesterol reached levels that were high-normal or intermediary between levels observed in normal and homozygous NPC fibroblasts. The partial expression of these metabolic errors in the heterozygous genotype relevantly links these errors to the primary mutation of this disorder.

    Title Studies on Hydroxyethyl Starch. Part I: Molecular Characterization by Size Exclusion Chromatography Coupled with Low-angle Laser Light Scattering.
    Date June 1985
    Journal Arzneimittel-forschung
    Excerpt

    Two commercially available hydroxyethyl starch (HES) preparations (in clinical use as plasma expanders) specified with Mw = 450,000/MS = 0.7 and Mw = 200,000/MS = 0.5, respectively, and three experimental HES-samples (supposingly similar to the commercial product with the specification 450,000/0.7, except of one with MS = 0.5) were studied. The latter were prepared via acid or enzymatic hydrolysis of waxy-maize starch. Each of the samples was characterized by its intrinsic viscosity and molar substitution, and was studied with low-angle laser light scattering (LALLS) and with size exclusion chromatography (SEC) coupled with LALLS. The weight-average molecular weight Mw of the commercial samples was found to be 60-80% higher than the value given in the product declaration. This discrepancy can be explained by the argument that previous measurements were not carried out at sufficiently small scattering angles to enable reliable extrapolation to zero angle. The calibration functions Mw(v) of the individual HES-samples measured by SEC/LALLS-coupling are identical over a broad range of the elution volume v and are used for calibration of conventional SEC in a subsequent paper. The small, but detectable differences in the Mw(v)-functions indicate interesting differences between these HES-preparations with respect to the effective hydrodynamic density of the branched HES-molecules.

    Title [effect of Benzbromarone on Serum Uric Acid Level and Uric Acid Excretion of Patients with Gout]
    Date January 1971
    Journal Deutsche Medizinische Wochenschrift (1946)

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