Surgeons, Urologist
7 years of experience

South Green
Ct Children's Medical Center / Urology
282 Washington St
Hartford, CT 06106
860-545-9520
Locations and availability (2)

Education ?

Medical School Score Rankings
Tufts University (2003)
  • Currently 3 of 4 apples
Top 50%

Awards & Distinctions ?

Associations
American Urological Association

Affiliations ?

Dr. Nelson is affiliated with 2 hospitals.

Hospital Affilations

Score

Rankings

  • Hartford Hospital
    Urology
    200 Retreat Ave, Hartford, CT 06102
    • Currently 4 of 4 crosses
    Top 25%
  • Institute of Living Hartford Hospital's Mental Health Network
    200 Retreat Ave, Hartford, CT 06106
  • Publications & Research

    Dr. Nelson has contributed to 48 publications.
    Title The Impact of Surgical Approach and Urinary Diversion on Patient Outcomes in Pediatric Pyeloplasty.
    Date November 2011
    Journal The Journal of Urology
    Excerpt

    Recent comparisons of the impact of the surgical approach on pediatric pyeloplasty outcomes have generally incorporated a form of internal ureteral drainage. We hypothesized that the surgical approach does not affect outcomes in children who undergo unstented pyeloplasty and stenting offers no long-term benefit in those with pediatric pyeloplasty.

    Title Immunomodulatory Dietary Polysaccharides: a Systematic Review of the Literature.
    Date January 2011
    Journal Nutrition Journal
    Excerpt

    A large body of literature suggests that certain polysaccharides affect immune system function. Much of this literature, however, consists of in vitro studies or studies in which polysaccharides were injected. Their immunologic effects following oral administration is less clear. The purpose of this systematic review was to consolidate and evaluate the available data regarding the specific immunologic effects of dietary polysaccharides.

    Title Spectral Purity for Far Infrared Grating Spectroscopy.
    Date June 2010
    Journal Applied Optics
    Excerpt

    A far ir grating spectrometer of the Ebert type has been constructed to cover the range from 10 cm(-1) to 160 cm(-1). A technique for quantitatively measuring the spectral purity of this instrument is presented. Filter curves for the reflection filter gratings used with the spectrometer are given for radiations polarized parallel and perpendicular to the groove length. It is found that, with a 20 degrees blaze angle and the plane of incidence of the radiation parallel to the groove length, polarization effects due to the filters are small. In fact, the filters are very efficient and possess sharp cutoff characteristics in both polarizations when used in this fashion. The measured spectral purity of the spectrometer is better than 95%0 throughout most of its operating range. This result is consistent with purity estimates from absorption experiments on water vapor lines in the region from 195 micro to 300 micro. Experimental results pertaining to far ir solidstate physics research are also briefly discussed.

    Title Histone Deacetylases 1 and 2 Form a Developmental Switch That Controls Excitatory Synapse Maturation and Function.
    Date August 2009
    Journal The Journal of Neuroscience : the Official Journal of the Society for Neuroscience
    Excerpt

    The structural assembly of synapses can be accomplished in a rapid time frame, although most nascent synapses formed during early development are not fully functional and respond poorly to presynaptic action potentials. The mechanisms that are responsible for this delay in synapse maturation are unknown. Histone deacetylases (HDACs) regulate the activity state of chromatin and repress gene expression through the removal of acetyl groups from histones. Class I HDACs, which include HDAC1 and HDAC2, are expressed in the CNS, although their specific role in neuronal function has not been studied. To delineate the contribution of HDAC1 and HDAC2 in the brain, we have used pharmacological inhibitors of HDACs and mice with conditional alleles to HDAC1 and HDAC2. We found that a decrease in the activities of both HDAC1 and HDAC2 during early synaptic development causes a robust facilitation of excitatory synapse maturation and a modest increase in synapse numbers. In contrast, in mature neurons a decrease in HDAC2 levels alone was sufficient to attenuate basal excitatory neurotransmission without a significant change in the numbers of detectable nerve terminals. Therefore, we propose that HDAC1 and HDAC2 form a developmental switch that controls synapse maturation and function acting in a manner dependent on the maturational states of neuronal networks.

    Title Mef2c, a Transcription Factor That Facilitates Learning and Memory by Negative Regulation of Synapse Numbers and Function.
    Date August 2008
    Journal Proceedings of the National Academy of Sciences of the United States of America
    Excerpt

    Learning and memory depend on the activity-dependent structural plasticity of synapses and changes in neuronal gene expression. We show that deletion of the MEF2C transcription factor in the CNS of mice impairs hippocampal-dependent learning and memory. Unexpectedly, these behavioral changes were accompanied by a marked increase in the number of excitatory synapses and potentiation of basal and evoked synaptic transmission. Conversely, neuronal expression of a superactivating form of MEF2C results in a reduction of excitatory postsynaptic sites without affecting learning and memory performance. We conclude that MEF2C limits excessive synapse formation during activity-dependent refinement of synaptic connectivity and thus facilitates hippocampal-dependent learning and memory.

    Title Folding Domain B of Protein A on a Dynamically Partitioned Free Energy Landscape.
    Date March 2008
    Journal Proceedings of the National Academy of Sciences of the United States of America
    Excerpt

    The B domain of staphylococcal protein A (BdpA) is a small helical protein that has been studied intensively in kinetics experiments and detailed computer simulations that include explicit water. The simulations indicate that BdpA needs to reorganize in crossing the transition barrier to facilitate folding its C-terminal helix (H3) onto the nucleus formed from helices H1 and H2. This process suggests frustration between two partially ordered forms of the protein, but recent varphi value measurements indicate that the transition structure is relatively constant over a broad range of temperatures. Here we develop a simplistic model to investigate the folding transition in which properties of the free energy landscape can be quantitatively compared with experimental data. The model is a continuation of the Muñoz-Eaton model to include the intermittency of contacts between structured parts of the protein, and the results compare variations in the landscape with denaturant and temperature to varphi value measurements and chevron plots of the kinetic rates. The topography of the model landscape (in particular, the feature of frustration) is consistent with detailed simulations even though variations in the varphi values are close to measured values. The transition barrier is smaller than indicated by the chevron data, but it agrees in order of magnitude with a similar alpha-carbon type of model. Discrepancies with the chevron plots are investigated from the point of view of solvent effects, and an approach is suggested to account for solvent participation in the model.

    Title Activity-dependent Suppression of Miniature Neurotransmission Through the Regulation of Dna Methylation.
    Date February 2008
    Journal The Journal of Neuroscience : the Official Journal of the Society for Neuroscience
    Excerpt

    DNA methylation is an epigenetic mechanism that plays a critical role in the repression of gene expression. Here, we show that DNA methyltransferase (DNMT) inhibition in hippocampal neurons results in activity-dependent demethylation of genomic DNA and a parallel decrease in the frequency of miniature EPSCs (mEPSCs), which in turn impacts neuronal excitability and network activity. Treatment with DNMT inhibitors reveals an activity-driven demethylation of brain-derived neurotrophic factor promoter I, which is mediated by synaptic activation of NMDA receptors, because it is susceptible to AP-5, a blocker of NMDA receptors. The specific effect of DNMT inhibition on spontaneous excitatory neurotransmission requires gene transcription and is occluded in the absence of the transcriptional repressor methyl-CpG-binding protein 2 (MeCP2). Interestingly, enhancing excitatory activity, in the absence of DNMT inhibitors, also produces similar decreases in DNA methylation and mEPSC frequency, suggesting a role for DNA methylation in the control of homeostatic synaptic plasticity. Furthermore, adding excess substrate for DNA methylation (S-adenosyl-L-methionine) rescues the suppression of mEPSCs by DNMT inhibitors in wild-type neurons, as well as the defect seen in MeCP2-deficient neurons. These results uncover a means by which NMDA receptor-mediated synaptic activity drives DNA demethylation within mature neurons and suppresses basal synaptic function.

    Title Targeted Biopsy of the Prostate: the Impact of Color Doppler Imaging and Elastography on Prostate Cancer Detection and Gleason Score.
    Date January 2008
    Journal Urology
    Excerpt

    OBJECTIVES: To compare detection of prostate cancer and distribution of Gleason scores with gray-scale, color Doppler, and elastographic imaging. METHODS: Prostate biopsy patients were evaluated with gray-scale, color Doppler, and elastographic imaging. Targeted biopsy cores were obtained along with six laterally directed systematic sextant cores. Pathologic results were correlated with imaging findings. RESULTS: Prostate cancer was detected in 60 of 137 patients (43.8%). Cancer was detected in 241 (14%) of 1703 biopsy cores, including 90 (20%) of 448 targeted cores, 106 (13%) of 818 sextant cores, and 45 (10%) of 437 transition zone cores. Sonographic abnormality was associated with cancer: gray-scale odds ratio (OR) = 3.19, P = 0.011; color Doppler OR = 1.86, P = 0.041; elastography OR = 2.53; P = 0.007. Although targeted cores were more likely than sextant cores to detect cancer (OR = 1.82, P = 0.004), no sonographic abnormality was found in 57 (53.8%) of 106 of positive sextant sites. A linear trend for increasing Gleason score was present with gray-scale (P <0.001) imaging, color Doppler imaging (P <0.005), and elastography (P <0.001). Abnormal color flow was strongly associated with Gleason score 8 to 10 lesions but not with lower-grade lesions. Elastography demonstrated a positive association with Gleason scores of 5 to 10. CONCLUSIONS: Targeted cores based on gray-scale, color Doppler, and elastographic imaging are more likely to return positive biopsy results as compared with systematic biopsy cores. Although color Doppler imaging and elastography are encouraging adjuncts to improve cancer detection, targeted biopsy alone is not sufficient to replace the traditional sextant biopsy technique.

    Title Use of Thermal Desorption Mass Spectrometry for the Detection of Free Acid Impurities in Pharmaceutical Products.
    Date April 2007
    Journal Analytical Chemistry
    Excerpt

    A method utilizing thermal desorption mass spectrometry (TDMS) for the detection and quantitation of free acid forms in pharmaceutical drug products formulated as salts is presented. Selective detection of neutral drug forms is possible because the volatility of a drug present in its free acid form is typically much higher than that of its corresponding salt forms, which have negligible volatility even at high temperatures. Tandem mass spectrometric detection allows selective quantitation of the desired free acid drug forms without significant interferences from formulation excipients. The application of the TDMS approach is demonstrated for a sodium salt of a representative, carboxylated drug molecule. Excellent sensitivity, specificity, and adequate linearity of detector signal as a function of micrograms of free acid added were demonstrated in the presence of the sodium salt of the drug and formulation excipients. The sensitivity of the method was demonstrated at free acid levels of 0.6% w/w (6 microg absolute mass). Tablet samples were analyzed by thermal desorption EI-MS/MS with reference to external standards using a commercially available quadrupole ion trap mass spectrometer. The relative drug form stabilities in three different tablet formulations were differentiated using this method; the salt-to-free acid form conversion ranged between less than the limit of detection to near complete conversion during the stability study.

    Title Development and Validation of a High-throughput Gc Measurement for Water Activity.
    Date April 2007
    Journal Journal of Pharmaceutical and Biomedical Analysis
    Excerpt

    The development and validation of a headspace GC method to measure the water activity of pharmaceutical samples is presented. Thermal and moisture transfer equilibration rates are shown to be critical variables in the measurement. Several different calibration schemes are discussed with their advantages and disadvantages. The high-throughput applications and experimental considerations of this approach are discussed. The method is shown to be a useful tool to measure a high throughput of water activity samples.

    Title Degradation of Vitamin D3 in a Stressed Formulation: the Identification of Esters of Vitamin D3 Formed by a Transesterification with Triglycerides.
    Date March 2007
    Journal Journal of Pharmaceutical and Biomedical Analysis
    Excerpt

    Four unknown degradants in the LC-UV profile of a stressed experimental tablet formulation that contains vitamin D3 have been identified by a combination of Ag+-cationization electrospray ionization (ESI) LC/MS and atmospheric pressure chemical ionization (APCI) LC/MS/MS. The peaks elute in the method chromatography in two pairs of two peaks. The first pair of peaks has m/z 511 while the second pair has m/z 539. The major, first peak of each set of peaks corresponds to the octanoate and decanoate ester of vitamin D3, respectively. These are formed by a transesterification with the two major fatty acid components (octanoate and decanoate) of the triglycerides present in the formulation. The formation of two degradation products with each fatty acid is due to the presence of both vitamin D3 (major component) and the isomeric pre-vitamin D3 (minor component) in the stressed formulation.

    Title Coan Promotions and the Authorship of the Presbeutikos.
    Date March 2007
    Journal Studies in Ancient Medicine
    Excerpt

    This article argues that the Presbeutikos Thessalou (Ambassadorial Oration of Thessalus), a seminal text of the Hippocratic pseudepigrapha, is an excerpt of the lost third century BCE historical work Ta Kôaka (History of Cos) of Macareus. It further argues that the rhetoric of the speech derives from ambassadorial speeches delivered by Coan embassies, of which Macareus was a member, on behalf of the Coan Asclepieion. It also suggests that the Presbeutikos' companion in the pseudepigrapha, the Epibomios (Speech from the Altar), may have a similar origin in Macareus' historical work.

    Title Nucleophilic Group Transfer Reactivity for Fibric Acid Derived Drug Molecules.
    Date October 2006
    Journal Journal of Pharmaceutical Sciences
    Excerpt

    A novel group transfer reaction is reported in which a drug molecule undergoes a thermally induced 2-methyl-2-yl-propionic acid group transfer from one drug molecule to the carboxylic acid functional group of another. The resulting product, the 2-carboxy isopropyl ester of the parent compound, can itself participate in further reactions to yield a series of homologous products. The structural requirements and solvent dependence of this reactivity were investigated, and the resulting implications for the reaction mechanism were discussed. The experimental data is consistent with solvent-assisted nucleophilic substitution reaction mechanism, where the solvent is a small molecule or a second drug molecule. Hydrogen bonding appears to play an important role in both intramolecular activation of the leaving group, as well as intermolecular interaction with the attacking nucleophile. The reactivity is found to be intrinsic to the 2-arenoxy-2-methylpropionic acid structure, which is common to the extended class of fibrate PPAR drug molecules, suggesting that the potential for this reactivity exists for many of these drug molecules as well.

    Title Evaluation of Solution Oxygenation Requirements for Azonitrile-based Oxidative Forced Degradation Studies of Pharmaceutical Compounds.
    Date September 2006
    Journal Journal of Pharmaceutical Sciences
    Excerpt

    AIBN and ACVA oxidative forced degradation models are examined for two drug molecules whose predominant oxidation chemistries arise from different reaction mechanisms (i.e., free radical vs. nucleophilic). Stress was conducted under a variety of initiator concentrations, and under ambient and pressurized oxygen atmospheres. In each case examined, the azonitrile initiator solutions served as a good predictive model of the major oxidative degradation products observed in pharmaceutical formulations. At low to moderate inititator concentrations, the degradation product distributions and degree of reactivity were similar for samples stored in ambient and pressurized oxygen environments. These results are rationalized with reference to the oxygen consumption kinetics of AIBN and ACVA solutions as a function of initiator concentration. The data suggests that ambient air provides sufficient oxygen to enable chain propagation of peroxy radicals in azonitrile solutions of concentrations appropriate to the forced degradation of pharmaceutical compounds.

    Title Mecp2-dependent Transcriptional Repression Regulates Excitatory Neurotransmission.
    Date August 2006
    Journal Current Biology : Cb
    Excerpt

    Mutations in the transcriptional repressor, methyl-CpG binding protein 2 (MeCP2), result in a neurodevelopmental disorder called Rett Syndrome (RTT) . Based on the neurological phenotypes observed in Rett patients, we examined the potential role of MeCP2 in synaptic function. We compared elementary properties of synaptic transmission between cultured hippocampal neurons from MeCP2 knockout and wild-type littermate control mice and found a decrease in the frequency of spontaneous excitatory synaptic transmission (mEPSCs) in neurons lacking MeCP2. We also detected a significant increase in the rate of short-term synaptic depression. To explore whether these functional effects can be attributed to MeCP2's role as a transcriptional silencer, we treated cultures with a drug that impairs histone deacetylation and examined spontaneous synaptic transmission. Treatment with this compound induced a similar decrease in mEPSC frequency in wild-type control cultures, but this decrease was occluded in MeCP2-deficient neurons. Interestingly, neither the loss of MeCP2 nor the drug treatment resulted in changes in mIPSC properties. Finally, by means of a lentivirus expressing Cre recombinase, we show that loss of MeCP2 function after neurodevelopment and synaptogenesis was sufficient to mimic the decrease in mEPSC frequency seen in constitutive MeCP2 KO neurons. Taken together, these results suggest a role for MeCP2 in control of excitatory presynaptic function through regulation of gene expression.

    Title Scaling Approach to the Folding Kinetics of Large Proteins.
    Date August 2006
    Journal Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
    Excerpt

    We study a nucleation-growth model of protein folding and extend it to describe larger proteins with multiple folding units. The model is of one of an extremely simple type in which amino acids are allowed just two states--either folded (frozen) or unfolded. Its energetics are heterogeneous and Gō-like, the energy being defined in terms of the number of atom-to-atom contacts that would occur between frozen amino acids in the native crystal structure of the protein. Each collective state of the amino acids is intended to represent a small free energy microensemble consisting of the possible configurations of unfolded loops, open segments, and free ends constrained by the cross-links that form between folded parts of the molecule. We approximate protein free energy landscapes by an infinite subset of these microensemble topologies in which loops and open unfolded segments can be viewed roughly as independent objects for the purpose of calculating their entropy, and we develop a means to implement this approximation in Monte Carlo simulations. We show that this approach describes transition state structures (phi values) more accurately and identifies folding intermediates that were unavailable to previous versions of the model that restricted the number of loops and nuclei.

    Title Alternate Pathways for Folding in the Flavodoxin Fold Family Revealed by a Nucleation-growth Model.
    Date May 2006
    Journal Journal of Molecular Biology
    Excerpt

    A recent study of experimental results for flavodoxin-like folds suggests that proteins from this family may exhibit a similar, signature pattern of folding intermediates. We study the folding landscapes of three proteins from the flavodoxin family (CheY, apoflavodoxin, and cutinase) using a simple nucleation and growth model that accurately describes both experimental and simulation results for the transition state structure, and the structure of on-pathway and misfolded intermediates for CheY. Although the landscape features of these proteins agree in basic ways with the results of the study, the simulations exhibit a range of folding behaviours consistent with two alternate folding routes corresponding to nucleation and growth from either side of the central beta-strand.

    Title Postnatal Loss of Methyl-cpg Binding Protein 2 in the Forebrain is Sufficient to Mediate Behavioral Aspects of Rett Syndrome in Mice.
    Date May 2006
    Journal Biological Psychiatry
    Excerpt

    Mutations in the methyl-CpG binding protein 2 (MeCP2) gene cause Rett syndrome (RTT), a neurodevelopmental disorder that is accompanied by a broad array of behavioral phenotypes, mainly affecting females. Methyl-CpG binding protein 2 is a transcriptional repressor that is widely expressed in all tissues.

    Title Atmospheric Concentrations and Deposition of Polycyclic Aromatic Hydrocarbons to the Mid-atlantic East Coast Region.
    Date November 2005
    Journal Environmental Science & Technology
    Excerpt

    Atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured at urban/industrial, suburban, coastal, and rural areas in New Jersey as part of the New Jersey Atmospheric Deposition Network. Concentrations of 36 PAH compounds were measured in the gas and particle phases in air and in precipitation at nine sites at regular intervals from October 1997 through May 2001. Gas-phase and particle-phase sigma36PAH concentrations ranged from 0.45 to 118 ng m(-3) and from 0.046 to 172 ng m(-3), respectively, and precipitation concentrations ranged from 11 to 16200 ng L(-1). PAH concentrations vary spatially across the region, with the highest concentrations occurring at the most heavily urban and industrial locations. Average gas absorption deposition ranged from 0.004 (naphthacene) to 5040 (methylphenanthrenes) ng m(-2) d(-1), and dry particle deposition PAH fluxes ranged from 0.11 (naphthacene) to 300 (benzo[b+k]fluoranthene) ng m(-2) d(-1) at the nine sites. Average atmospheric wet deposition PAH fluxes at the seven sites ranged from 0.40 (cyclopenta[cd]pyrene) to 140 (methylphenanthrenes) ng m(-2) d(-1). These represent the first comprehensive estimates of PAH deposition to New Jersey and the Mid-Atlantic East Coast.

    Title Gas-phase Reactivity of Charged Pi-type Biradicals.
    Date April 2005
    Journal Journal of the American Chemical Society
    Excerpt

    Four pi,pi-biradicals, 2,6-dimethylenepyridinium and the novel isomers N-(3-methylenephenyl)-3-methylenepyridinium, N-phenyl-3,5-dimethylenepyridinium, and N-(3,5-dimethylenephenyl)pyridinium ions, were generated and structurally characterized in a Fourier transform ion cyclotron resonance mass spectrometer. Their gas-phase reactivity toward various reagents was compared to that of the corresponding monoradicals, 2-methylenepyridinium, N-phenyl-3-methylenepyridinium, and N-(3-methylenephenyl)pyridinium ions. The biradicals reactivity was found to reflect their predicted multiplicity. The 2,6-dimethylenepyridinium ion, the only biradical in this study predicted to have a closed-shell singlet ground state, reacts significantly faster than the other biradicals, which are predicted to have triplet ground states. In fact, this biradical reacts at a higher rate than the analogous monoradical, which suggests that to avoid the costly uncoupling of its unpaired electrons, the biradical favors ionic mechanisms over barriered radical pathways. In contrast, the second-order reaction rate constants of the isomeric biradicals with triplet ground states are well approximated by those of the analogous monoradicals, although the final reaction products are sometimes different. This difference arises from rapid radical-radical recombination of the initial monoradical reaction products. The overall reactivity toward the hydrogen-atom donors benzeneselenol and tributylgermanium hydride is significantly greater for the radicals with the charged site in the same ring system as the radical site. This finding indicates that polar effects play an important role in controlling the reactivity of pi,pi-biradicals, just as has been demonstrated for sigma,sigma-biradicals.

    Title Efficient Expansion, Folding, and Unfolding of Proteins.
    Date March 2005
    Journal Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
    Excerpt

    We consider a nonstatistical, computationally fast experiment to identify important topological constraints in folding small globular proteins of about 100-200 amino acids. In this experiment, proteins are expanded mechanically along a path of steepest increase in the free space around residues. The pathways are often consistent with folding scenarios reported in kinetics experiments and most accurately describe obligatory or mechanic folding proteins. The results suggest that certain topological "defects" in proteins lead to preferred, entropically favorable channels down their free energy landscapes.

    Title Chlordanes in the Mid-atlantic Atmosphere: New Jersey 1997-1999.
    Date October 2004
    Journal Environmental Science & Technology
    Excerpt

    To characterize the atmospheric dynamics and behavior of chlordane compounds in the mid-Atlantic region of the United States, atmospheric concentrations were measured in 1997-1999 at three New Jersey locations as part of the New Jersey Atmospheric Deposition Network (NJADN) project. Observed concentrations of sigma-chlordanes (cischlordane + trans-chlordane + cis-nonachlor + transnonachlor) are log-normally distributed, with a geometric mean concentration of 77.1 pg m(-3) and range from 6.1 to 481 pg m(-3). Gas-phase species comprised 83% (+/-23%) of the sigma-chlordanes species across all samples at all location. Gas-phase sigma-chlordane concentrations are inversely proportional to temperature, with higher concentrations during periods of warmer air temperatures. Observed concentrations do not correlate with wind direction or air mass history, which suggests that observed concentrations in the New Jersey atmosphere are due to volatilization from soils and surfaces on the regional scale.

    Title Atmospheric Concentrations and Deposition of Polychorinated Biphenyls to the Hudson River Estuary.
    Date August 2004
    Journal Environmental Science & Technology
    Excerpt

    The first estimates of atmospheric deposition fluxes of polychlorinated biphenyls (PCBs) to the Hudson River Estuary are presented. Concentrations of PCBs were measured in air, aerosol, and precipitation at nine sites representing a variety of land-use regimes at regular intervals from October 1997 through May 2001. Highest concentrations in the gas phase were observed at urban sites such as Camden and Jersey City (sigmaPCB concentrations averaged 3250 and 1260 pg m(-3), respectively). In great portions of the state encompassing forested, coastal, and suburban environments, gas-phase sigmaPCB concentrations were essentially the same (averaging 150-220 pg m(-3)). This spatial trend suggests that atmospheric PCBs arise from highly localized, urban sources which influence atmospheric concentrations and deposition fluxes over a distance of a few tens of kilometers. Atmospheric sigmaPCB deposition fluxes (gas absorption + dry particle deposition + wet deposition) ranged from 7.3 to 340 microg m(-2) yr(-1) and increased with proximity to urban areas. While the magnitude of the fluxes increased with urbanization,the relative proportions of wet, dry, and gaseous deposition remained largely constant. Because the Hudson River Estuary is adjacent to urban areas such as Jersey City, it is subject to higher depositional fluxes of PCBs. These depositional fluxes are at least 2-10 times those estimated for the Chesapeake Bay and Lake Michigan. Inputs of PCBs to the Hudson River Estuary from the upper Hudson River and from wastewater treatment plants are 8-18 times atmospheric inputs, and volatilization of PCBs from the estuary exceeds atmospheric deposition of low molecular weight PCBs.

    Title Mechanistic Study of Stereoselective Gas-phase Reactions of Phosphenium Ions with Cis- and Trans-1,2-diaminocyclohexanes.
    Date February 2003
    Journal The Journal of Organic Chemistry
    Excerpt

    The 1,3-dioxolane-2-phosphenium ion, 1,3-benzodioxole-2-phosphenium ion, and o-biphenylenephosphenium ion are reported to react in a stereoselective manner with cis- and trans-1,2-diaminocyclohexanes in the gas phase in a Fourier transform ion cyclotron resonance mass spectrometer. Elimination of NH3 from an addition product was observed only for the trans isomer. Several reaction mechanisms were experimentally and computationally examined (B3LYP/6-31G(d)//HF/6-31G(d) + ZPVE level of theory). The most plausible mechanism is initiated by addition of one of the amino groups to the electrophilic phosphorus atom followed by proton transfer between the amino groups. A change to a diaxial conformation for the trans isomer facilitates anchimeric assistance by the now nucleophilic phosphorus atom as the C-N bond breaks to release NH3. Intramolecular proton transfer competes with the conformational change and ultimately leads to ethylene glycol elimination. The transition states for the critical steps of these two reactions are calculated to be nearly equal in magnitude, which rationalizes the observation of both reactions for the trans-diamine. In contrast, the adduct of the cis isomer can eliminate NH3 via a concerted 1,2-hydride shift without a need for a conformational change. However, the barrier associated with this reaction was found to be substantially greater than for proton transfer between the N- and O-atoms. The latter reaction dominates and ultimately leads to ethylene glycol elimination.

    Title Wet Deposition of Polychlorinated Biphenyls in Urban and Background Areas of the Mid-atlantic States.
    Date January 2003
    Journal Environmental Science & Technology
    Excerpt

    Spatial and temporal trends of polychlorinated biphenyl (PCB) concentrations in precipitation were measured at urban and background sites as part of the New Jersey Atmospheric Deposition Network (NJADN). The volume weighted mean concentration (VWM) of sigmaPCBs (sum of PCBs) based on precipitation measurements at three background sites was in the range of 0.30-0.50 ng/L. Concentrations in precipitation at two urban-industrial sites were on average 7-43 times higher than background concentrations. Wet deposition fluxes of sigmaPCBs at the two urbanized sites were 16 +/- 3.4 and 3.9 +/- 0.72 microg/m2-yr, while the background flux was approximately 0.30 microg/m2-yr. On average, 97% of the total atmospheric washout (WT) of PCBs resulted from particle scavenging. The fraction of atmospheric PCBs on particles was the best predictor of atmospheric washout in both urban (log WT = 0.71 (+/- 0.049) log psi + 4.9 (+/- 0.11); r2 = 0.81) and nonurban areas (log W(T) = 0.77 (+/- 0.083) log psi + 5.6 (+/- 0.16); r2 = 0.64). Wet deposition fluxes of sigmaPCBs are of the same order of magnitude as dry-particle deposition fluxes in all land-use regimes.

    Title Air-water Exchange of Polycyclic Aromatic Hydrocarbons in the New York-new Jersey, Usa, Harbor Estuary.
    Date February 2002
    Journal Environmental Toxicology and Chemistry / Setac
    Excerpt

    Polycyclic aromatic hydrocarbons (PAHs, n = 36) were measured in the gas and particle phases in the atmosphere and the dissolved and particle phases in the waters of the New York-New Jersey Harbor Estuary, USA, during a weeklong intensive field campaign in July 1998. Mean total (gas + particulate) phenanthrene and pyrene concentrations were 3.3 and 0.33 ng/m3, respectively, over Raritan Bay, and 14 and 1.1 ng/ml, respectively, over New York Harbor. Similar PAH profiles (p values < 0.01) in the atmospheric gas phase and the dissolved phase in water demonstrate the close coupling of the air and water compartments. Air-water exchange fluxes of PAHs estimated using shore-based air data lead to erroneous flux estimates when compared to those derived using over-water air samples. The gross absorptive air-water flux dominates atmospheric loadings (wet, dry particle, gas absorption) to the estuary for PAHs of molecular weight < 234 g/mol. Dry particle deposition is increasingly more important for the higher-molecular-weight, particle-bound PAH species. Gross volatilization dominates gross absorption for the majority of PAHs in the New York-New Jersey Harbor Estuary.

    Title Dynamic Air-water Exchange of Polychlorinated Biphenyls in the New York-new Jersey Harbor Estuary.
    Date February 2002
    Journal Environmental Science & Technology
    Excerpt

    Simultaneous measurements of polychlorinated biphenyls (PCBs) in the air and water over Raritan Bay and New York Harbor were taken in July 1998, allowing the first determinations of air-water exchange fluxes for this heavily impacted system. Average gas-phase concentrations of sigmaPCBs were 1.0 ng m(-3) above Raritan Bay and 3.1 ng m(-3) above New York Harbor. A similar gradient was observed for dissolved water concentrations (1.6 and 3.8 ng L(-1), respectively). Shallow slopes of log K(oc) vs log K(ow) plots indicated a colloidal contribution to the dissolved concentrations, and a three-phase partitioning model was therefore applied. PCBs associated with colloids ranged from 6% to 93% for trichloro- to nonachlorobiphenyls, respectively. Air-water gas exchange fluxes of sigmaPCBs exhibited net volatilization for both Raritan Bay at +400 ng m(-2) day(-1) and New York Harbor at +2100 ng m(-2) day(-1). The correction for the colloidal interactions decreased the volatilization flux of sigmaPCBs by about 15%. Net air-water exchange fluxes of PCBs are expected to remain positive throughout the year due to the large water-air fugacity gradient and relatively constant seasonal water concentrations. The volatilization fluxes are approximately 40 times greater than atmospheric deposition of PCBs via both wet and dry particle deposition, suggesting that the estuary acts as a net source of PCBs to the atmosphere year-round.

    Title Are High-dose Toxic Exposures Always Associated with Reactive Airways Dysfunction Syndrome (rads)?
    Date January 2002
    Journal Archives of Environmental Health
    Excerpt

    Bottling plant workers were evaluated for respiratory symptoms following an accidental exposure to a chlorine dioxide aerosol. Six exposed employees underwent medical and occupational histories, skin testing to common allergens, spirometry before and after use of bronchodilators, and methacholine challenge. The reported exposure to chlorine dioxide ranged from 30 min to 12 hr. Physical examinations were all normal. Four workers had positive prick skin tests to common aeroallergens. None of the workers demonstrated significant changes in forced expiratory volume in 1 sec following use of bronchodilators, and none experienced methacholine hyperresponsiveness. These cases suggest that the occurrence of reactive airways dysfunction syndrome is unpredictable and may not always occur in heavily exposed individuals.

    Title A Fourier-transform Ion Cyclotron Resonance Study of the 3,5-didehydrophenyl Cation.
    Date May 2001
    Journal Journal of the American Society for Mass Spectrometry
    Excerpt

    The 3,5-didehydrophenyl cation has been generated in good purity via sustained off-resonance irradiation for collision-activated dissociation of 3,5-dinitrobenzoyl chloride in a Fourier-transform ion cyclotron resonance mass spectrometer. Differences in the ion-molecule reactivity of this species from that of its cyclic and acyclic isomers allowed isomeric distinction to be achieved. This study represents the first definitive identification of this fundamentally interesting, doubly aromatic ion. However, the formation of the 3,5-didehydrophenyl cation was found to be the exception rather than the rule, with most 1,3,5-substituted benzenes yielding mainly acyclic C6H3+ isomers under electron ionization conditions. This mixed ion population was attributed to isomerization of fragmentation intermediates rather than any intrinsic instability of the 3,5-didehydrophenyl cation.

    Title Thermoregulation and Heat Exchange in a Nonuniform Thermal Environment During Simulated Extended Eva. Extravehicular Activities.
    Date October 2000
    Journal Aviation, Space, and Environmental Medicine
    Excerpt

    Nonuniform heating and cooling of the body, a possibility during extended duration extravehicular activities (EVA), was studied by means of a specially designed water circulating garment that independently heated or cooled the right and left sides of the body. The purpose was to assess whether there was a generalized reaction on the finger in extreme contradictory temperatures on the body surface, as a potential heat status controller.

    Title Proposed Mechanism for Stability of Proteins to Evolutionary Mutations.
    Date September 1998
    Journal Proceedings of the National Academy of Sciences of the United States of America
    Excerpt

    It is shown that the sequence-ordering tendencies induced by design into different fast-folding, thermally stable native structures interfere. This interference results in a type of quasiorthogonality between optimal native structures, which divides sequence space into fast-folding, thermally stable families surrounded by slow-folding, low stability shells. A concrete example of this effect is provided by using a simple alpha carbon type model in which a complete correspondence is established between sequence and structure. It is speculated that gaps can occur in the space of protein-like sequences separating the sequence families and resulting in a mechanism for stability and diversity of protein sequence information.

    Title Injection Drug Users in the Midwest: an Epidemiologic Comparison of Drug Use Patterns in Four Ohio Cities.
    Date March 1995
    Journal Journal of Psychoactive Drugs
    Excerpt

    Variations in the drug use patterns of injection drug users (IDUs) can have important implications for public health efforts aimed at reducing drug abuse and the transmission of the human immunodeficiency virus. This article describes and compares the characteristics of IDUs living in four Ohio cities and compares African-American and White IDUs at a statewide level. Data from 2,001 IDUs who were recruited for the National AIDS Demonstration Research project between 1989 and 1991 in Columbus, Cleveland, Cincinnati, and Dayton were compared on a number of variables by city and by ethnicity using descriptive statistics and ANCOVA analysis. Significant differences among IDUs in the four cities exist for the use of alcohol, marijuana, cocaine, crack, heroin, speedball, other opioids, shooting gallery use, "safer" needle practices, treatment history, and self-help participation. Differences by ethnicity emerged on all variables except marijuana use, overall injection frequency, and incarceration experience. The results suggest that dramatic differences exist between African-American and White IDUs, and among IDUs in cities relatively close together, regardless of ethnicity. These findings should be considered when developing policy and programs for prevention and treatment activities targeting IDUs.

    Title Anirolac Vs. Naproxen for Postpartum Uterine Pain.
    Date August 1987
    Journal Clinical Pharmacology and Therapeutics
    Excerpt

    Anirolac, a new nonsteroidal anti-inflammatory drug, was evaluated for relative efficacy, safety, and time course of analgesia. In a stratified, randomized, parallel, double-blind trial, 120 hospitalized women with moderate or severe postpartum uterine pain were treated with single oral doses of anirolac, 50 or 100 mg, naproxen sodium, 550 mg, or placebo. Using verbal scales, patients rated pain intensity, pain relief, and side effects at regular intervals for 6 hours. Highest summed analgesic ratings over placebo were induced by anirolac, 100 mg (P less than or equal to 0.001), and naproxen (P less than or equal to 0.001), followed by anirolac, 50 mg (P less than or equal to 0.005). At each assessment after the first hour, anirolac, 50 and 100 mg, and naproxen induced significantly stronger analgesia than did placebo. Statistically significantly more drowsiness was reported with all three active agents than with placebo. Our results suggest that, for postpartum uterine pain, analgesia with anirolac, 50 or 100 mg, is equivalent to that with naproxen, 550 mg.

    Title Evaluation of a New Approach to Geriatric Drug Education.
    Date July 1983
    Journal Drug Information Journal
    Title Evaluation of Factors Influencing the Patterns of Use of Drug and Poison Information Resources.
    Date July 1983
    Journal Drug Information Journal
    Title The Impact of Video Technology on the Use of Drug Information Resources.
    Date February 1981
    Journal Drug Information Journal
    Title Epidemiology of Pcp Abuse: the Midwest Perspective.
    Date January 1981
    Journal Journal of Psychedelic Drugs
    Title Charcoal Hemoperfusion: a Method for Removing Pcp from the Blood and Body in Overdose Cases.
    Date January 1981
    Journal Journal of Psychedelic Drugs
    Title Consumer Focus of a University Drug and Poison Information Center.
    Date November 1980
    Journal American Journal of Hospital Pharmacy
    Excerpt

    The consumer-oriented aspect of a university drug and poison information center is described. The University of Cincinnati Medical Center began its 24-hour consumer drug information telephone service in 1972. It is staffed by seven full-time employees, and pharmacists and pharmacy residents of nearby hospitals handle evening and weekend calls. All participating personnel are trained in structured programs. The $78,000 annual budget for the consumer drug information service is funded exclusively from external sources such as mental health agencies, foundations, and donations. Of 40,719 calls handled by the center in 1979, 83% were from the public. The total annual call volume has increased by 250% since 1972. In telephone follow-up of consumer calls, 73% of persons claimed they followed verbatim the advice given. Of calls during 1972, 1974, 1977, and 1979, 32.2% concerned drug abuse; 28.6%, identification of ingredients; and 10.9%, efficacy. Data from a three-month study in 1979 showed that the goal perceived by the information provider was to satisfy the curiosity of the caller 63.6% of the time (35.6% of the time immediate action was indicated). The authors believe that the center promotes appropriate use of physicians and pharmacists as sources of information for consumers.

    Title The Influence of Human and Data Retrieval Resources on the Patterns of Use of Drug Information.
    Date January 1980
    Journal Drug Information Journal
    Title Abuse and Pulmonary Complications of Injecting Pentazocine and Tripelennamine Tablets.
    Date September 1979
    Journal Clinical Toxicology
    Excerpt

    A current practice among drug abusers in certain Midwestern and Eastern cities is the intravenous injection of aqueous mixtures prepared from tablets of pentazocine and tripelennamine. Patients present with acute hypoxic episodes and symptoms suggesting physical dependence to pentazocine. Two cases are presented illustrating acute respiratory distress with hypoxia. Available evidence indicates that the respiratory syndrome is produced by talc from the injected tablets. Respiratory support and short-term oxygen therapy have been effective in managing this syndrome. Approaches to the treatment of pentazocine dependence and the role of the antihistamine in potentiating the narcotic activity are also discussed. Physicians, drug abuse counselors, and others should be aware of the abuse potential and pulmonary damage which can result from the intravenous use of this drug combination.

    Title Popping and Snorting Volatile Nitrites: a Current Fad for Getting High.
    Date November 1978
    Journal The American Journal of Psychiatry
    Excerpt

    In certain social circles a variety of volatile nitrites are being used extensively to expand creativity, stimulate music appreciation, promote a sense of abandon in dancing, and intensify sexual experience. Soon after amyl nitrite (the prototype of this group) became a prescription drug, legally produced substitutes appeared and were sold as room odorizers. Analyses of eight of these substitutes showed them to contain isomers of butyl or amyl alcohol and a corresponding nitrite. The authors describe the context of use of these products and their desired and adverse effects.

    Title Drug Information to Patient Care Areas Via Television: Preliminary Evaluation of Two Years' Experience.
    Date June 1978
    Journal Special Libraries
    Title A Comparison of Four Toxicology Resources in Respect to Rates of Retrieval and Time Required.
    Date February 1978
    Journal The Journal of Pediatrics
    Excerpt

    An evaluation was conducted fo four periodically updated poison control resources widely used by pediatricians, emergency room personnel, and poison information/control centers; i.e., Poisindex, ToxiFile, Clinical Toxicology of Commercial Products, and the National Clearinghouse for Poison Control Centers' cards. The frequency of finding entries for substances known to be involved in accidental pediatric ingestions, the extent of the content and management information, and the time required to obtain the information were determined for the four resources. Poisindex was more complete than the other resources. ToxiFile was more useful than the remaining two resources, although the latter should be useful in over 70% of accidental toxic ingestions by children.

    Title Proposed Nmr Determination of the Exchange Parameters in Hexagonal-close-packed 3he.
    Date
    Journal Physical Review. B, Condensed Matter
    Title A Pilot Project: Continuing Education for Pharmacists on Substance Abuse Prevention.
    Date
    Journal Substance Abuse : Official Publication of the Association for Medical Education and Research in Substance Abuse
    Excerpt

    The American Association of Colleges of Pharmacy advocates that pharmacists can have a significant impact on substance abuse prevention provided they receive adequate training. Continuing education programs are needed to enable practicing pharmacists to augment their limited education. This paper examines the process the Society of Teachers of Family Medicine (STFM) used to develop a pilot continuing education program for pharmacists. With limited literature and a small number of pharmacy teaching about substance abuse, input on topics and training methods was obtained from a convenience sample of practicing pharmacists to enhance the information from the pharmacist faculty regarded as content experts. Results of this pilot study revealed lack of agreement between faculty and practicing pharmacists regarding the prioritizing of content and educational methods. Consequently, input must be obtained from targeted audiences instead of relying solely on the advice of identified academic content experts when designing continuing educational programs. Other professions should consider this process when designing continuing education programs. Pharmacists are poised to play an important role in the prevention of substance abuse problems, but they need continuing education about substance abuse.

    Title Solvent Effects on the Aibn Forced Degradation of Cumene: Implications for Forced Degradation Practices.
    Date
    Journal Journal of Pharmaceutical Sciences
    Excerpt

    Solvent effects on the AIBN and ACVA forced degradation of cumene are explored. The degradant formation rates of the three cumene oxidative degradants, cumene hydroperoxide, acetophenone, and 2-phenyl-2-propanol are reported. The relative abundance and ratios of these three degradants provide insight into the fate of the peroxy radical oxidants generated by the forced stress system, and suggest that alkoxy radicals are actually a significant source of the observed reactivity. The presence of even 1% methanol in the forced stress solvent significantly quenches this alkoxy radical reactivity, dramatically reducing the overall degradation rate and leaving cumene hydroperoxide as the major product of the oxidation reaction. The origin of this significant solvent effect on the oxidation product distribution is shown to be related to the preferential H-atom abstraction from methanol and its trace impurities by any alkoxy radicals present in the reaction solution. The implications for these observations are explored with the intent of producing more predictive oxidative forced stress experiments. (c) 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci.

    Title Diurnal Variability of Pharmaceutical, Personal Care Product, Estrogen and Alkylphenol Concentrations in Effluent from a Tertiary Wastewater Treatment Facility.
    Date
    Journal Environmental Science & Technology
    Excerpt

    Hourly samples of tertiary wastewater effluent were analyzed for 30 pharmaceuticals, personal care products, estrogenic steroids, and alkylphenols in order to better understand the rate at which these compounds enter the environment. Several distinct patterns of daily cycling were observed, and were characterized as three separate categories. The concentrations of compounds such as trimethoprim, sulfamethoxazole, naproxen, estrone, and triclosan varied greatly during a daily cycle, with relative standard deviations exceeding 100% of their daily mean. Less extreme daily cycles were seen for other compounds such as azithromycin, atenolol, tert-octylphenol, iopromide and gemfibrozil. Peak concentrations for most compounds occurred in the early evening (5-8 pm). However, some compounds including carbamazepine, primidone, fluoxetine, and triclocarban exhibited little or no variability.


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