Browse Health
Surgical Specialist
16 years of experience
Accepting new patients


Education ?

Medical School
Univ Rovira I Virgili, Fac De Med Y Cien De La Salud (1996)

Awards & Distinctions ?

Patients' Choice Award (2010 - 2011)
Compassionate Doctor Recognition (2010)
Cardiothoracic Surgery Network
American Board of Surgery
Society of Thoracic Surgeons
American Board of Thoracic Surgery

Affiliations ?

Dr. Cox is affiliated with 1 hospitals.

Hospital Affiliations

  • Memorial Hospital Central
  • Publications & Research

    Dr. Cox has contributed to 41 publications.
    Title Empiric, Broad-spectrum Antibiotic Therapy with an Aggressive De-escalation Strategy Does Not Induce Gram-negative Pathogen Resistance in Ventilator-associated Pneumonia.
    Date January 2011
    Journal Surgical Infections

    Early, empiric, broad-spectrum antibiotics followed by de-escalation to pathogen-specific therapy is the standard of care for ventilator-associated pneumonia (VAP). In our surgical intensive care unit (SICU), imipenem-cilastatin (I-C) in combination with tobramycin (TOB) or levofloxacin (LEV) has been used until quantitative bronchoalveolar lavage results are finalized, at which time de-escalation occurs to pathogen-specific agents. With this practice, however, alterations in antimicrobial resistance remain a concern. Our hypothesis was that this strict regimen does not alter antimicrobial susceptibility of common gram-negative VAP pathogens in our SICU.

    Title Multifactorial Determinants of Protein Expression in Prokaryotic Open Reading Frames.
    Date October 2010
    Journal Journal of Molecular Biology

    A quantitative description of the relationship between protein expression levels and open reading frame (ORF) nucleotide sequences is important for understanding natural systems, designing synthetic systems, and optimizing heterologous expression. Codon identity, mRNA secondary structure, and nucleotide composition within ORFs markedly influence expression levels. Bioinformatic analysis of ORF sequences in 816 bacterial genomes revealed that these features show distinct regional trends. To investigate their effects on protein expression, we designed 285 synthetic genes and determined corresponding expression levels in vitro using Escherichia coli extracts. We developed a mathematical function, parameterized using this synthetic gene data set, which enables computation of protein expression levels from ORF nucleotide sequences. In addition to its practical application in the design of heterologous expression systems, this equation provides mechanistic insight into the factors that control translation efficiency. We found that expression is strongly dependent on the presence of high AU content and low secondary structure in the ORF 5' region. Choice of high-frequency codons contributes to a lesser extent. The 3' terminal AU content makes modest, but detectable contributions. We present a model for the effect of these factors on the three phases of ribosomal function: initiation, elongation, and termination.

    Title Significant Pediatric Morbidity and Mortality from Intracranial Ballistic Injuries Caused by Nonpowder Gunshot Wounds. A Case Series.
    Date September 2009
    Journal Pediatric Neurosurgery

    Nonpowder (ball-bearing and pellet) weapons derive their source of energy from compressed air or carbon dioxide. Such weapons are dangerous toys that cause serious injuries and even death to children and adolescents. A retrospective chart review study was undertaken to describe nonpowder gun injuries at a southwestern US urban level I adult and pediatric trauma center. Specific emphasis was placed on intracranial injuries. Over the past 6 years, a total of 29 pediatric and 7 adult patients were identified as having nonpowder firearm injuries. The patient population was overwhelmingly male (89.7%; mean age, 11 years). Overall, 17 out of 29 pediatric patients (56.8%) sustained serious injury. Nine patients (30.0%) required operation, 6 (20.7%) sustained significant morbidity, and there were 2 deaths (6.9%). Injuries to the brain, eye, head, and neck were the most common sites of injury (65.6%). Specific intracranial injuries in 3 pediatric patients are described that resulted in the death of 2 children. We suggest that age warning should be adjusted to 18 years or older for unsupervised use to be considered safe of these potentially lethal weapons.

    Title The Utility of Diagnostic Laparoscopy in the Evaluation of Anterior Abdominal Stab Wounds.
    Date January 2009
    Journal American Journal of Surgery

    To assess if diagnostic laparoscopy (DL) is superior to nonoperative modes (serial abdominal examination with/without computed axial tomography [CAT] and diagnostic peritoneal lavage) in determining the need for therapeutic laparotomy (TL) after anterior abdominal stab wound (ASW).

    Title Protein Fabrication Automation.
    Date March 2007
    Journal Protein Science : a Publication of the Protein Society

    Facile "writing" of DNA fragments that encode entire gene sequences potentially has widespread applications in biological analysis and engineering. Rapid writing of open reading frames (ORFs) for expressed proteins could transform protein engineering and production for protein design, synthetic biology, and structural analysis. Here we present a process, protein fabrication automation (PFA), which facilitates the rapid de novo construction of any desired ORF from oligonucleotides with low effort, high speed, and little human interaction. PFA comprises software for sequence design, data management, and the generation of instruction sets for liquid-handling robotics, a liquid-handling robot, a robust PCR scheme for gene assembly from synthetic oligonucleotides, and a genetic selection system to enrich correctly assembled full-length synthetic ORFs. The process is robust and scalable.

    Title Routine Follow-up Imaging is Unnecessary in the Management of Blunt Hepatic Injury.
    Date February 2006
    Journal The Journal of Trauma

    BACKGROUND: Nonoperative management of hemodynamically stable patients with blunt hepatic injuries has become the standard of care over the past decade. However, controversy regarding the role of in-hospital follow-up computed tomographic (CT) scans as a part of this nonoperative management scheme is ongoing. Although many institutions, including our own, have advocated routine in-hospital follow-up scans, others have suggested a more selective policy. Over time, we have perceived a low yield from follow-up studies. The hypothesis for this study is that routine follow-up imaging of asymptomatic patients is unnecessary. METHODS: All patients selected for nonoperative management of blunt hepatic injury were evaluated for utility of follow-up CT scans over a 4-year period. RESULTS: There were 530 stable patients with hepatic injury on admission CT scans in which follow-up scans were obtained within a week of admission. All injuries were classified according to the revised American Association for the Surgery of Trauma Organ Injury Scale: 102 (19.2%) grade I, 181 (34.1%) grade II, 158 (29.8%) grade III, 74 (13.9%) grade IV, and 15 (2.8%) grade V. Follow-up scans showed that most injuries were either unchanged (51%) or improved (34.7%). Only three patients underwent intervention based on their follow-up scans: two patients had arteriography (one with therapeutic embolization) and one had percutaneous drainage. Each of those patients had clinical signs or symptoms that were indicative of ongoing hepatic abnormality. CONCLUSION: These data demonstrate that, regardless of injury grade, routine in-hospital follow-up scans are not indicated as part of the nonoperative management of blunt liver injuries. Follow-up scans are indicated for patients who develop signs or symptoms suggestive of hepatic abnormality.

    Title Binding of Herpes Simplex Virus-1 Us11 to Specific Rna Sequences.
    Date October 2005
    Journal Nucleic Acids Research

    Herpes simplex virus-1 US11 is a RNA-binding protein with a novel RNA-binding domain. US11 has been reported to exhibit sequence- and conformation-specific RNA-binding, but the sequences and conformations important for binding are not known. US11 has also been described as a double-stranded RNA (dsRNA)-binding protein. To investigate the US11-RNA interaction, we performed in vitro selection of RNA aptamers that bind US11 from a RNA library consisting of >10(14) 80 base sequences which differ in a 30 base randomized region. US11 bound specifically to selected aptamers with an affinity of 70 nM. Analysis of 23 selected sequences revealed a strong consensus sequence. The US11 RNA-binding domain and < or =46 bases of selected RNA containing the consensus sequence were each sufficient for binding. US11 binding protected the consensus motif from hydroxyl radical cleavage. RNase digestions of a selected aptamer revealed regions of both single-stranded RNA and dsRNA. We observed that US11 bound two different dsRNAs in a sequence non-specific manner, but with lower affinity than it bound selected aptamers. The results define a relatively short specific sequence that binds US11 with high affinity and indicate that dsRNA alone does not confer high-affinity binding.

    Title Iscomatrix Adjuvant: an Adjuvant Suitable for Use in Anticancer Vaccines.
    Date December 2004
    Journal Vaccine

    Human Papillomavirus type 16 (HPV16) E6 and E7 oncoproteins are associated with cervical cancer development and progression and can therefore be used as target antigens for cancer immunotherapy. In this study we evaluated the immunogenicity in mice, of different vaccine formulations using recombinant HPV16 derived E6E7 or E7GST fusion proteins. When co-administered with ISCOMATRIX adjuvant, these E6E7 proteins consistently induced E7 specific CTL, in vivo tumor protection, antibody and DTH responses. ISCOMATRIX adjuvant has been developed for use in the formulation of novel human vaccines and has been evaluated for safety and toxicity in human trials. A formulation containing aluminum hydroxide (Al(OH)3) gave a lesser degree of E7 specific antibody, and no local E7 specific CTL response but similar DTH and tumor protection. These findings demonstrate the potential of ISCOMATRIX adjuvant to stimulate both cellular and humoral immune responses to endogenously processed target antigens, and hence is the preferred adjuvant when CTL responses are desirable.

    Title The Appropriate Diagnostic Threshold for Ventilator-associated Pneumonia Using Quantitative Cultures.
    Date June 2004
    Journal The Journal of Trauma

    BACKGROUND: The use of quantitative cultures of the bronchoalveolar lavage (BAL) effluent to distinguish between posttraumatic inflammatory response and ventilator-associated pneumonia (VAP) is becoming more common. However, the diagnostic threshold of either 10 or 10 colonies/mL remains debatable. Because mortality from VAP is related to treatment delay, some have chosen a lower diagnostic threshold (>10 colonies/mL). This may result in unnecessary antibiotic use with its sequelae: increased resistant organisms, antibiotic-related complications, and increased costs. The purpose of this study is to determine the optimal diagnostic threshold for VAP diagnosis using quantitative cultures of the BAL effluent. METHODS: Data on patients with fiberoptic bronchoscopy with BAL are maintained in a prospectively collected database at our Level I trauma center. This database was reviewed for timing and frequency of BAL and the colony counts of each organism identified. Indication for bronchoscopy was clinical evidence of VAP. VAP was defined as >10 colonies/mL in the BAL effluent. A false-negative BAL was defined as any patient who had <10 colonies/mL and developed VAP with the same organism up to 7 days after the previous culture. RESULTS: Over a 46-month period, 526 patients underwent 1,372 fiberoptic bronchoscopy procedures with BAL. Of these, 72% were male patients, 91% followed blunt injury, and mean age and Injury Severity Score were 43 years and 30, respectively. Overall mortality was 14%. There were 1,898 organisms identified (42% were gram-positive and 58% were gram-negative). VAP was diagnosed in 38% of BAL. Overall, there were 43 episodes in 38 patients defined as false-negative (3%). The false-negative rate was 9% in patients with 10 organisms. The most common false-negative organisms were Pseudomonas and Acinetobacter species. CONCLUSION: The VAP diagnostic threshold for quantitative BAL in trauma patients should be >10 colonies/mL. One may consider a threshold of >10 colonies/mL in severely injured patients with Pseudomonas or Acinetobacter species.

    Title Aant: the Amino Acid-nucleotide Interaction Database.
    Date January 2004
    Journal Nucleic Acids Research

    We have created an Amino Acid-Nucleotide Interaction Database (AANT; http://aant.icmb.utexas. edu/) that categorizes all amino acid-nucleotide interactions from experimentally determined protein-nucleic acid structures, and provides users with a graphic interface for visualizing these interactions in aggregate. AANT accomplishes this by extracting individual amino acid-nucleotide interactions from structures in the Protein Data Bank, combining and superimposing these interactions into multiple structure files (e.g. 20 amino acids x 5 nucleotides) and grouping structurally similar interactions into more readily identifiable clusters. Using the Chime web browser plug-in, users can view 3D representations of the superimpositions and clusters. The unique collection and representation of data on amino acid-nucleotide interactions facilitates understanding the specificity of protein-nucleic acid interactions at a more fundamental level, and allows comparison of otherwise extremely disparate sets of structures. Moreover, by modularly representing the fundamental interactions that govern binding specificity it may prove possible to better engineer nucleic acid binding proteins.

    Title Antibody Responses to Hpv6b E Polyproteins and Production of Monoclonal Antibodies.
    Date May 2003
    Journal Hybridoma and Hybridomics

    A range of fusion constructs (expressed in Escherichia coli) were produced that contained two or more HPV6b E proteins, producing a single continuous amino acid sequence corresponding to the sequences of the individual E proteins. The constructs also included a C-terminal hexahistidine tag fused in-frame to aid purification. The fusion proteins (polyproteins) were semipurified by Ni(++) metal affinity chromatography under denaturing conditions. Immunization of BALB/c mice with these polyproteins resulted in the production of specific E protein antibodies. The draining lymph nodes from these mice were used to produce monoclonal antibodies (MAbs). The specificity of the polyclonal and MAbs was confirmed by immunoblotting and by screening for reaction with a series of synthetic peptides of E proteins. HPV E polyproteins were found to be immunogenic and immunization with the polyproteins resulted in specific antibody responses to the component E proteins.

    Title Automated Selection of Aptamers Against Protein Targets Translated in Vitro: from Gene to Aptamer.
    Date November 2002
    Journal Nucleic Acids Research

    Reagents for proteome research must of necessity be generated by high throughput methods. Aptamers are potentially useful as reagents to identify and quantitate individual proteins, yet are currently produced for the most part by manual selection procedures. We have developed automated selection methods, but must still individually purify protein targets. Therefore, we have attempted to select aptamers against protein targets generated by in vitro transcription and translation of individual genes. In order to specifically immobilize the protein targets for selection, they are also biotinylated in vitro. As a proof of this method, we have selected aptamers against translated human U1A, a component of the nuclear spliceosome. Selected sequences demonstrated exquisite mimicry of natural binding sequences and structures. These results not only reveal a potential path to the high throughput generation of aptamers, but also yield insights into the incredible specificity of the U1A protein for its natural RNA ligands.

    Title Toward Automated Nucleic Acid Enzyme Selection.
    Date March 2002
    Journal Biological Chemistry

    Methods for automation of nucleic acid selections are being developed. The selection of aptamers has been successfully automated using a Biomek 2000 workstation. Several binding species with nanomolar affinities were isolated from diverse populations. Automation of a deoxyribozyme ligase selection is in progress. The process requires eleven times more robotic manipulations than an aptamer selection. The random sequence pool contained a 5' iodine residue and the ligation substrate contained a 3' phosphorothioate. Initially, a manual deoxyribozyme ligase selection was performed. Thirteen rounds of selection yielded ligators with a 400-fold increase in activity over the initial pool. Several difficulties were encountered during the automation of DNA catalyst selection, including effectively washing bead-bound DNA, pipetting 50% glycerol solutions, purifying single strand DNA, and monitoring the progress of the selection as it is performed. Nonetheless, automated selection experiments for deoxyribozyme ligases were carried out starting from either a naive pool or round eight of the manually selected pool. In both instances, the first round of selection revealed an increase in ligase activity. However, this activity was lost in subsequent rounds. A possible cause could be mispriming during the unmonitored PCR reactions. Potential solutions include pool redesign, fewer PCR cycles, and integration of a fluorescence microtiter plate reader to allow robotic 'observation' of the selections as they progress.

    Title Cytotoxic T Cell Polyepitope Vaccines Delivered by Iscoms.
    Date January 2002
    Journal Vaccine

    CD8 alphabeta cytotoxic T lymphocyte (CTL) polyepitope or polytope vaccines have traditionally been delivered using recombinant vector or DNA based delivery modalities. Here we show the delivery of polytope vaccines in the form of either synthetic polypeptides or recombinant polytope proteins by ImmunoStimulatory COMplexes (ISCOMs(R)). Induction of multiple protective CTL responses by these polytope-ISCOM formulations were comparable to viral vector or DNA based delivery modalities as assessed by IFNgamma ELISpot, chromium release and viral challenge assays. Measurement of CTL responses specific for the different epitopes revealed immunodominance patterns, which were largely independent of the vaccine vector or the order of the epitopes in the polytope. ISCOMs thus emerge as a viable human delivery modality for protein-based polytope vaccines.

    Title Paying Doctors More: Use of Musculoskeletal Specialists and Increased Physician Pay to Decrease Workers' Compensation Costs.
    Date January 2002
    Journal Journal of Occupational and Environmental Medicine / American College of Occupational and Environmental Medicine

    Previous studies evaluating workers' compensation care systems used retrospective controls. We performed a concurrent effectiveness study comparing a WC system that used visiting musculoskeletal specialists to assist primary care physicians with a typical discounted-fee, WC, managed-care system. In the new specialist-direct system, physicians could not profit from self-referral, but were paid 35% to 69% more per patient visit than doctors in the discounted-fee clinics. All claims filed by all employees of two hotels for 2 years were examined. Patients had self-selected either a specialist-direct or a discounted-fee clinic, and the entire cost of the claim was assigned to either system of care. Claim costs were 63% lower in the specialist-direct system (P < 0.001). Medical costs were 45% less (P < 0.014), and indemnity 85% less (P < 0.001), in this system. Claims were closed nearly 6 months faster in the specialist-direct system (P < 0.0001). Indemnity claims were more common in the discounted-fee system (P < 0.0001). Claimant and injury characteristics were not significantly different between the systems. This new care model is a cost-effective alternative to discounted WC managed care. Discounting the services of the primary treating physician may result only in cost-shifting, not cost-saving.

    Title Dna Computation Function.
    Date July 2001
    Journal Current Biology : Cb
    Title The Complexities of Dna Computation.
    Date May 1999
    Journal Trends in Biotechnology

    Over the past few years, a handful of insightful researchers have bridged the gap between biological computing theory and actual DNA-based computation. By using ingenious encoding techniques and clever molecular-biological manipulations, simple versions of computationally complex problems have been experimentally approached or resolved. However, the technical problems revealed during the execution of these scientific set pieces make it unlikely that DNA will ever rival silicon for the solution of any real-world problem.

    Title Automated Rna Selection.
    Date January 1999
    Journal Biotechnology Progress

    In vitro selection can be used to generate nucleic acid ligands (aptamers) to target molecules ranging in size and structure from cations to cells. However, the selection process is repetitive and time-consuming. We have automated a protocol for in vitro selection using an augmented Beckman Biomek 2000 pipetting robot. The automated selection procedure requires the integration of four devices and the optimization of four molecular biology methods, and is one of the most complex automated protocols attempted to date. Initial attempts at selection yielded robust replication parasites, but optimization of the automated selection procedure suppressed the emergence of these parasites and led to the selection of true nucleic acid ligands. Automated selection can now be used to generate nucleic acid aptamers in days rather than weeks or months.

    Title Iscoms: an Adjuvant with Multiple Functions.
    Date December 1998
    Journal Journal of Leukocyte Biology

    Aluminum salts are currently the only widely used adjuvant for human vaccines. Over the past 10-15 years, a large research effort has attempted to find novel adjuvants with ability to induce a broad range of immune responses, including cell-mediated immunity. The immunostimulating complex or ISCOM is one adjuvant with multiple adjuvant properties. ISCOMs are open cage-like complexes typically with a diameter of about 40 nm that are built up by cholesterol, lipid, immunogen, and saponins from the bark of the tree Quillaia saponaria Molina. ISCOMs have been demonstrated to promote antibody responses and induce T helper cell as well as cytotoxic T lymphocyte responses in a variety of experimental animal models, and have now progressed to phase I and II human trials. This review describes recent developments in the understanding of the structure, composition, and preparation of ISCOMs and will cover important aspects of the understanding of the adjuvant functions of ISCOMs and how they act on the immune system.

    Title The Gain of Three Mitochondrial Introns Identifies Liverworts As the Earliest Land Plants.
    Date September 1998
    Journal Nature

    The first evidence for the emergence of land plants (embryophytes) consists of mid-Ordovician spore tetrads (approximately 476 Myr old). The identity of the early plants that produced these spores is unclear; they are sometimes claimed to be liverworts, but there are no associated megafossils, and similar spores can be produced by a diversity of plants. Indeed, the earliest unequivocal megafossils of land plants consist of early vascular plants and various plants of uncertain affinity. Different phylogenetic analyses have identified liverworts, hornworts and bryophytes as each being the first lineage of land plants; the consensus of these conflicting topologies yields an unresolved polychotomy at the base of land plants. Here we survey 352 diverse land plants and find that three mitochondrial group II introns are present, with occasional losses, in mosses, hornworts and all major lineages of vascular plants, but are entirely absent from liverworts, green algae and all other eukaryotes. These results indicate that liverworts are the earliest land plants, with the three introns having been acquired in a common ancestor of all other land plants, and have important implications concerning the early stages of plant evolution.

    Title Adjuvants--a Classification and Review of Their Modes of Action.
    Date May 1997
    Journal Vaccine

    Since early this century, various substances have been added to vaccines and certain formulations have been devised in an attempt to render vaccines more effective. Despite a plethora of options, only aluminium salts have gained acceptance as human vaccine adjuvants and even veterinary vaccines are largely dependent upon the use of aluminium salts. Currently, many new vaccines are under development and there is a desire to simplify vaccination schedules both by increasing the number of components per vaccine and decreasing the number of doses required for a vaccine course. New, more effective adjuvants will be required to achieve this.

    Title Snake Envenomation in Cats and Its Detection by Rapid Immunoassay.
    Date January 1997
    Journal Australian Veterinary Journal

    To determine the usefulness of a snake venom detection kit (SVDK) in the management of envenomed cats.

    Title Evaluation of a Novel Diagnostic Test for Canine Parvovirus.
    Date December 1994
    Journal Veterinary Microbiology

    The CPV ELISA detection kit (CSL Ltd., Melbourne Australia) was developed as a rapid field test for the detection of canine parvovirus (CPV) antigen in canine faecal samples. The kit utilises a novel concept in enzyme immunoassay (ELISA) where the conjugate is lyophilised along with the solid-phase capture antibody in the test well. The CPV ELISA was compared to the haemagglutination assay (HA) test using electron microscopy (EM) and/or virus isolation (VI) to confirm infection. The CPV ELISA had a sensitivity of 87% and a specificity of 100% compared to 87% and 63% respectively for the HA. The poor specificity of the HA results in a low positive predictive value of 51% compared to 100% for the CPV ELISA. The CPV ELISA requires no specialised equipment, is simple to perform and provides a visible result in less than 15 minutes.

    Title Removal of False-positive Reactions from Plasma in an Enzyme Immunoassay for Bovine Interferon-gamma.
    Date December 1992
    Journal Journal of Immunological Methods

    A monoclonal antibody-based sandwich enzyme immunoassay (EIA) for bovine interferon-gamma (IFN-gamma) has been developed and can be used in conjunction with a whole blood culture system to diagnose tuberculosis in cattle. During its development, normal bovine plasma samples were tested to establish background levels of circulatory IFN-gamma. Of 191 samples tested, 81 (42.4%) were positive (OD > 0.1) when tested undiluted in intact monoclonal antibody (IgG1)-coated wells compared to only 8 (4.2%) in F(ab')2-coated wells, which suggested non-specific interference in the EIA rather than circulatory IFN-gamma. Reactivity of all remaining samples was removed by diluting plasmas 1/2 with 1% casein-PBS-0.05% Tween 20 supplemented with an optimum amount (5%) of normal mouse serum (NMS). Serum pools derived from BALB/c, DBA/2, C3H/HeJ, CBA/CaH and Swiss, but not C57BL/6J, mice were found to inhibit equally the reactions of five strong false-positive bovine plasma samples but had no effect on the titre of IFN-gamma in the sample. Sera from other species tested were less effective. This suggests that the interfering factors possess a high degree of specificity, since the immunoglobulin heavy chain of IgG1 produced by all these five strains of mice are allotypically identical and different to IgG1 produced by C57BL/6J mice. The use of F(ab')2 antibody fragments to coat plate wells and sample diluent containing 5% NMS has resulted in an EIA for bovine IFN-gamma that is virtually free from false-positive reactions, has a high degree of reproducibility and a sample detection limit equivalent to approximately 80 pg/ml recombinant bovine IFN-gamma.

    Title A Novel Format for a Rapid Sandwich Eia and Its Application to the Identification of Snake Venoms.
    Date March 1992
    Journal Journal of Immunological Methods

    A rapid sandwich enzyme immunoassay format is described where conjugate is lyophilised within the well in which the test reaction will occur. The format is straight forward to manufacture, has a prolonged shelf life, and eliminates one incubation and wash step from the usual test procedure. The technology has been applied to the development of a rapid assay for the identification of snake venom in clinical specimens. The resultant assay was specific and sensitive, provided rapid results and was appropriate for field use.

    Title A Comparison of the Sensitivity and Specificity of Enzyme Immunoassays and Time-resolved Fluoroimmunoassay.
    Date November 1991
    Journal Journal of Immunological Methods

    Time-resolved fluoroimmunoassay (TR-FIA) and various enzyme immunoassays (EIA) were compared in order to determine the detection system which showed the greatest degree of sensitivity without sacrificing specificity. The system chosen for the evaluation of these assays was the detection of antibodies to human immunodeficiency virus (HIV). For EIA, horseradish peroxidase (HRP) and alkaline phosphatase (AP) were investigated, each with a number of different substrates. HRP with its fluorogenic substrate, 3-(p-hydroxyphenyl)propionic acid (HPPA) was 1.6 times (p less than 0.01) more sensitive than with 3,3',5,5'-tetramethylbenzidine (TMB) and four times (p less than 0.001) more sensitive than with 2,2'-azino-di(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS). AP with its fluorogenic substrate, 4-methylumbelliferyl phosphate (4MeUP), was 6-7 times (p less than 0.001) more sensitive than with phenolphthalein monophosphate (PMP) and 8-13 times (p less than 0.001) more sensitive than with p-nitrophenyl phosphate (pNPP). TR-FIA with Eu3(+)-labelled anti-human IgG was equivalent in sensitivity to HRP with TMB and AP with 4MeUP.

    Title Evaluation of a Commercial Enzyme-linked Immunosorbent Assay for Johne's Disease.
    Date April 1991
    Journal Journal of Clinical Microbiology

    A new commercial kit for diagnosis of bovine paratuberculosis (Johne's disease), called the Johne's Absorbed EIA (enzyme immunoassay; Commonwealth Serum Laboratories, Parkville, Victoria, Australia), was evaluated by using serum specimens from the National Repository for Paratuberculosis Specimens. The evaluation was specifically designed to measure test sensitivity and specificity for detection of dairy cattle with subclinical paratuberculosis. The case definition of subclinical bovine paratuberculosis was isolation of Mycobacterium paratuberculosis from fecal samples or internal organs of cattle without diarrhea or chronic weight loss. Animals designed as free of the disease originated exclusively from four herds in Wisconsin that were certified to be free of disease. The kit had a sensitivity of 47.3% for serum specimens from 150 infected cattle. The test detected 59.7% of animals that shed M. paratuberculosis in their feces, as defined by conventional fecal culture, at the time of serum collection. Testing of 196 serum specimens from cattle without paratuberculosis yielded two false-positive results; the test specificity was thus 99.0%. Decision analysis procedures on the economics of using the kit in a test-and-cull disease control program indicated it would be cost-effective in any herd with a true paratuberculosis prevalence of greater than or equal to 3%. Comparison of the sensitivity and specificity of the Johne's Absorbed EIA with those of other tests for detection of subclinical paratuberculosis indicated that it may be the most accurate commercially available test at present and better than standard complement fixation test used in the United States.

    Title Expression of Foreign Dna in Chlamydomonas Reinhardtii.
    Date March 1990
    Journal Fems Microbiology Letters

    A chimeric octopine synthase-neomycin phosphotransferase (ocs-nptII) gene was used to transform Chlamydomonas reinhardiii to kanamycin resistance. Southern hybridization using DNA isolated from one transformant, T6.1, indicated that the entire ocs-nptII gene and at least part of the plasmid were integrated into nuclear DNA. Neomycin phosphotransferase II activity has been detected in T6.1 cell extracts. Northern hybridizations, employing a radiolabeled ocs-nptII sequence, revealed a T6.1 transcript of approximately the same size as a homologous transcript isolated from E. coli carrying the nptII gene. Although T6.1 is an extremely rare example of a stable C. reinhardtii transformant, its occurrence nevertheless indicates that bacterial genes can be expressed in the nucleus of the alga.

    Title An Enzyme Immunoassay for Isotyping Mouse Monoclonal Antibodies.
    Date October 1989
    Journal Medical Laboratory Sciences

    A rapid, simply performed and relatively inexpensive enzyme immunoassay for isotyping mouse monoclonal antibodies is described, based on the urease/urea system. Because of the high sensitivity (less than 0.1 microgram/ml of immunoglobulin can be detected in cell culture medium) no treatment of the hybridoma supernatant sample is required prior to assay, and the isotype of a mouse immunoglobulin can be determined in about thirty minutes.

    Title The Infectivity of Encephalitozoon Cuniculi in Vivo and in Vitro.
    Date April 1986
    Journal Zeitschrift Für Parasitenkunde (berlin, Germany)

    The infectivity of Encephalitozoon cuniculi grown in cell cultures was determined in cultured cells and in wild and domestic rabbits. The ratio of the total to tissue culture viable count was 1,300 (median of seven determinations). The mean ratio of intact spore count to total count, as determined by electron microscopy was 0.12. Although variation between infectivity experiments was large, the median animal infective dose contained 51 FFU (cell culture focus-forming units) for wild rabbits (Oryctolagus cuniculus) and 40 FFU for domestic rabbits. These two infectivities were not statistically different.

    Title An Evaluation of the Use of a Ph Indicator for the Detection of Beta-lactamase in Enzyme Immunoassay.
    Date December 1985
    Journal Journal of Immunological Methods

    The use of a mixed pH indicator containing bromocresol purple and bromothymol blue was evaluated for the detection of beta-lactamase activity in enzyme immunoassays (EIA) based on this enzyme. The EIA was found to correlate well with a bioassay for antibodies to tetanus toxoid in sheep sera. Results could be read spectrophotometrically at 450 nm or visually as a colour change from dark blue to yellow. The mixed pH indicator was found to have a number of desirable features including good stability, ease of preparation and a sharp colour change which makes the system suitable for visual determination of titration end points.

    Title A Rapid Semi Quantitative Capillary Enzyme Immunoassay for Digoxin.
    Date February 1984
    Journal Clinica Chimica Acta; International Journal of Clinical Chemistry

    A rapid and sensitive enzyme immunoassay (EIA) which does not require highly trained personnel or specialised instrumentation is described for the estimation of digoxin in serum, plasma or whole blood samples. The method is based on the ability of digoxin in a clinical sample to inhibit the binding of urease-conjugated sheep-antidigoxin immunoglobulin to a glass capillary tube coated internally with a human serum albumin-digoxin conjugate. The bound enzyme activity can then be measured using a substrate solution containing urea and a pH indicator, most suitably bromocresol purple. The enzymic hydrolysis of urea produces ammonia which causes a vivid yellow to purple colour change in the pH indicator. Plasma samples from 92 patients receiving digoxin were screened in parallel with reference plasma containing 1.3 or 3.8 nmol/l digoxin. The results were available within a total test time of 30 min, and showed excellent correlation with those obtained by radioimmunoassay.

    Title An Investigation of the Use of Urease-antibody Conjugates in Enzyme Immunoassays.
    Date January 1983
    Journal Journal of Immunological Methods

    The development of urease (E.C. as a label for enzyme immunoassay (EIA) procedures is described and the use of such conjugates illustrated with examples. Urease catalyzes the hydrolysis of urea to carbon dioxide and ammonia. The production of ammonia may be detected readily by a pH shift which we have found best indicated by the vivid colour change (yellow to purple) of bromocresol purple incorporated in the substrate solution. This enzyme-substrate system offers a number of important advantages. The substrate in aqueous solution is stable, titration end points are sharp and readily visible and the enzyme is not inhibited by sodium azide. Thus, test reagents may be prepared with this preservative and stored ready to use. Urease of high specific activity is commercially available and because it does not occur in mammalian tissues, it is suitable for use in EIA tests to detect cell-associated antigens and their antibodies. Finally, the enzyme reaction may be stopped by the addition of organomercurial preservatives, thus allowing storage of developed tests for later examination.

    Title The Ultrastructure of Encephalitozoon Cuniculi Growing in Renal Tubules of Rabbits.
    Date June 1981
    Journal Zeitschrift Für Parasitenkunde (berlin, Germany)

    A wild type rabbit infected orally with cell culture-grown Encephalitozoon cuniculi. Twelve weeks after infection the rabbit was killed and blocks of kidney tissue were fixed for histology and electron microscopy. E. cuniculi were observed within kidney collecting tubule cells. The ultrastructure and development of E. cuniculi in these cells was similar to that described in cultured cells and peritoneal macrophages.

    Title Resolution of Distinct Selenium-containing Formate Dehydrogenases from Escherichia Coli.
    Date May 1981
    Journal Journal of Bacteriology

    Formate dehydrogenase, a component activity of two alternative electron transport pathways in anaerobic Escherichia coli, has been resolved as two distinguishable enzymes. One, which was induced with nitrate reductase as a component of the formate-nitrate reductase pathway, utilized phenazine methosulfate (PMS) in preference to benzyl viologen (BV) as an artificial electron acceptor and appeared to be exclusively membrane-bound. A second formate dehydrogenase, which was induced as a component of the formate hydrogenlyase pathway, appeared to exist both as a membrane-bound form and as a cytoplasmic enzyme; the cytoplasmic activity was resolved completely from the PMS-linked activity on a sucrose gradient. When E. coli was grown in the presence of 75Se-selenite, a 110,000-dalton selenopeptide, previously shown to be a component of the PMS-linked enzyme, was induced and repressed with this activity. In contrast, an 80,000-dalton selenopeptide was induced and repressed with the BV-linked activity and exhibited a distribution similar to the BV-linked formate dehydrogenase in cell fractions and in sucrose gradients. The results indicate that the two formate dehydrogenases are distinguishable on the basis of their artificial electron acceptor specificity, their cellular localization, and the size of their respective selenoprotein components.

    Title An Immunofluorescence Study of Influenza Virus Filament Formation.
    Date April 1980
    Journal Archives of Virology

    A study is described in which filamentous forms of influenza virus were observed budding from host cell surfaces. Cell cultures infected with influenza virus were stained by indirect immunofluorescence using an antiserum to purified haemagglutinin. Filaments greater than 100 micrometers in length, with several branch points along their length were observed; the number and length of filaments varied according to the virus strain and the time after infection. Examination of infected cells by electron microscopy confirmed the presence of branched structures with an ultrastructure typical of filamentous forms of influenza virus. The immunofluorescence technique was quicker than thin section electron microscopy and was a more sensitive procedure for the detection of filamentous forms of influenza virus than electron microscopy using negative stain. It also enabled the antigenic composition of the filaments to be observed.

    Title An Investigation of the Route and Progression of Encephalitozoon Cuniculi Infection in Adult Rabbits.
    Date December 1979
    Journal The Journal of Protozoology

    Rabbits infected either orally or intratracheally with cell culture-grown Encephalitozoon cuniculi were monitored regularly for serum antibody levels and E. cuniculi in the urine. Their responses were compared with intravenously inoculated and uninoculated control rabbits. All rabbits receiving E. cuniculi developed serum antibodies, generally within 3 weeks, and excreted E. cuniculi by 6 weeks. In the acute stage of infection, the organs most affected were lung, kidney and liver; the brain and gut were unaffected. However, during chronic infection, the brain, kidney, and heart were the only organs found to be involved. Antibody levels were very high at this stage. Thus both the oral and tracheal routes may be normal routes of infection with E. cuniculi in adult rabbits.

    Title Wall Structure of the Sporonts of Encephalitozoon Cuniculi Grown in Human Fibroblasts.
    Date March 1977
    Journal Journal of General Microbiology
    Title Iscoms and Other Saponin Based Adjuvants.
    Journal Advanced Drug Delivery Reviews

    Saponins are chemically a heterogeneous group of sterol glycosides and triterpene glycosides which are common constituents of plants. One source of triterpenoid saponins obtained from the bark of Quillaia saponaria Molina (the soap bark tree) have been known to cause substantial enhancement of immune responses since the 1920s. Despite their use in animal vaccines, the development of saponin-based formulations for human vaccines has been impeded by their complexity and concerns about toxicity. This review briefly covers the use of saponins for animal vaccines but focuses mainly on the development of these adjuvants for use in man. Important aspects include preparation of purified or highly defined saponin fractions, improved understanding of the relationships between adjuvant activity, toxicity and structure of saponins and formulation of saponins into structures with reduced toxicity such as ISCOMs. Recent developments in the understanding of cellular interactions, cytokine induction and the in vivo localisation of saponin containing formulations will also be reviewed.

    Title Uptake and Adjuvant Activity of Orally Delivered Saponin and Iscom Vaccines.
    Journal Advanced Drug Delivery Reviews

    Saponins are a highly heterogenous group of glycosides which are common in plants and have been known to have adjuvant properties since the 1920s. The immunostimulating complex or ISCOM is a particulate adjuvant/antigen delivery system. ISCOMs are open cage-like complexes typically with a diameter of about 40 nm which are built up by cholesterol, lipid, immunogen and saponins from the bark of Quillaia saponaria Molina (soap bark tree). ISCOMs and saponins are used as adjuvants in some commercial veterinary vaccines and have been examined as adjuvants in a large number of human experimental vaccines. This review describes the current status and potential of saponin and ISCOMs as adjuvants for orally-administered vaccines with special reference to the induction of local and systemic immune responses and interactions with the intestinal epithelium. The structure and composition of saponins and ISCOMs will also be reviewed.

    Title Recognition Confidence Under Violated and Confirmed Memory Expectations.
    Journal Journal of Experimental Psychology. General

    Individuals' memory experiences typically covary with those of others' around them, and on average, an item is more likely to be familiar if a companion recommends it as such. Although it would be ideal if observers could use the external recommendations of others' as statistical priors during recognition decisions, it is currently unclear how or if they do so. Furthermore, understanding the sensitivity of recognition judgments to such external cues is critical for understanding memory conformity and eyewitness suggestibility phenomena. To address this we examined recognition accuracy and confidence following cues from an external source (e.g., "Likely Old") that forecast the likely status of upcoming memory probes. Three regularities emerged. First, hit and correct-rejection rates expectedly fell when participants were invalidly versus validly cued. Second, hit confidence was generally higher than correct-rejection confidence, regardless of cue validity. Finally, and most noteworthy, cue validity interacted with judgment confidence such that validity heavily influenced the confidence of correct rejections but had no discernible influence on the confidence of hits. Bootstrap-informed Monte Carlo simulation supported a dual process recognition model under which familiarity and recollection processes counteract to heavily dampen the influence of external cues on average reported confidence. A 3rd experiment tested this model using source memory. As predicted, because source memory is heavily governed by contextual recollection, cue validity again did not affect confidence, although as with recognition it clearly altered accuracy. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

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