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1.
Oncoimmunology ; 9(1): 1682383, 2020.
Article in English | MEDLINE | ID: mdl-32002292

ABSTRACT

Background: Nivolumab and pembrolizumab, two PD1 inhibitors, trigger immune-related adverse events in approximately 50% of patients. Our objective was to determine whether these immune-related adverse events are associated with patient outcomes. Patients and Methods: Retrospective cohort study, realized at the Institut Universitaire du Cancer de Toulouse, of all the patients treated with nivolumab or pembrolizumab off clinical trials. We included patients (i) diagnosed with unresectable stage III or stage IV melanoma or with recurrent stage IIIB or stage IV non-small cell lung cancer (ii) on nivolumab 3mg/kg or pembrolizumab 2mg/kg every 2 or 3 weeks respectively. Results: Of the 311 patients included (of 641 eligible subjects), 120 (38.6%) had melanoma and 191 (61.4%) had non-small cell lung cancer; 241 (77.5%) were treated with nivolumab with a median follow-up of 24 months (20-29). We observed 166 immune-related adverse events in 116 (37.3%) patients, categorized as "early" (onset before 12 weeks in melanoma and before 8 weeks in lung cancer) in 63 (54.3%) patients. Early and late adverse events were significantly associated with an increase in overall survival: adjusted hazard ratio 0.58 [0.41-0.84] (p = .003) and 0.28 [0.16-0.50] (p < .001) respectively. The overall response rate was significantly increased in patients with an immune-related adverse event (53.9% vs 12.9%, p < .001) Conclusions: This study validates the association between immune-related adverse events and anti-PD1 efficacy in real-life, especially if these events are delayed. Our results, along with further studies on the place of immunosuppressive drugs in the therapeutic strategy, could improve the management of these adverse events.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Melanoma , Carcinoma, Non-Small-Cell Lung/drug therapy , Humans , Lung Neoplasms/drug therapy , Melanoma/drug therapy , Prognosis , Retrospective Studies
3.
Appl Microbiol Biotechnol ; 101(11): 4799-4813, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28213734

ABSTRACT

The diversity of Dehalococcoides mccartyi (Dhc) and/or other organohalide respiring or associated microorganisms in parallel, partial, or complete trichloroethene (TCE) dehalogenating systems has not been well described. The composition of Dhc populations and the associated bacterial community that developed over 7.5 years in the top layer (0-10 cm) of eight TCE-fed columns were examined using pyrosequencing. Columns biostimulated with one of three carbon sources, along with non-stimulated controls, developed into complete (ethene production, whey amended), partial (cis-dichloroethene (DCE) and VC, an emulsified oil with nonionic surfactant), limited (<5 % cis-DCE and 95 % TCE, an emulsified oil), and non- (controls) TCE dehalogenating systems. Bioaugmentation of one column of each treatment with Bachman Road enrichment culture did not change Dhc populations nor the eventual degree of TCE dehalogenation. Pyrosequencing revealed high diversity among Dhc strains. There were 13 OTUs that were represented by more than 1000 sequences each. Cornell group-related populations dominated in complete TCE dehalogenating columns, while Pinellas group related Dhc dominated in all other treatments. General microbial communities varied with biostimulation, and three distinct microbial communities were established: one each for whey, oils, and control treatments. Bacterial genera, including Dehalobacter, Desulfitobacterium, Sulfurospirillum, Desulfuromonas, and Geobacter, all capable of partial TCE dehalogenation, were abundant in the limited and partial TCE dehalogenating systems. Dhc strain diversity was wider than previously reported and their composition within the community varied significantly depending on the nature of the carbon source applied and/or changes in the Dhc associated partners that fostered different biogeochemical conditions across the columns.


Subject(s)
Biodegradation, Environmental , Chloroflexi/genetics , Chloroflexi/metabolism , Microbial Consortia , Trichloroethylene/chemistry , Trichloroethylene/metabolism , Bacteria/genetics , Bacteria/isolation & purification , Geobacter/genetics , Geobacter/isolation & purification , Halogenation , High-Throughput Nucleotide Sequencing , RNA, Ribosomal, 16S , Water Pollutants, Chemical
4.
Appl Environ Microbiol ; 83(4)2017 02 15.
Article in English | MEDLINE | ID: mdl-27913413

ABSTRACT

The extent of arsenic contamination in drinking water and its potential threat to human health have resulted in considerable research interest in the microbial species responsible for arsenic reduction. The arsenate reductase gene (arrA), an important component of the microbial arsenate reduction system, has been widely used as a biomarker to study arsenate-reducing microorganisms. A new primer pair was designed and evaluated for quantitative PCR (qPCR) and high-throughput sequencing of the arrA gene, because currently available PCR primers are not suitable for these applications. The primers were evaluated in silico and empirically tested for amplification of arrA genes in clones and for amplification and high-throughput sequencing of arrA genes from soil and groundwater samples. In silico, this primer pair matched (≥90% DNA identity) 86% of arrA gene sequences from GenBank. Empirical evaluation showed successful amplification of arrA gene clones of diverse phylogenetic groups, as well as amplification and high-throughput sequencing of independent soil and groundwater samples without preenrichment, suggesting that these primers are highly specific and can amplify a broad diversity of arrA genes. The arrA gene diversity from soil and groundwater samples from the Cache Valley Basin (CVB) in Utah was greater than anticipated. We observed a significant correlation between arrA gene abundance, quantified through qPCR, and reduced arsenic (AsIII) concentrations in the groundwater samples. Furthermore, we demonstrated that these primers can be useful for studying the diversity of arsenate-reducing microbial communities and the ways in which their relative abundance in groundwater may be associated with different groundwater quality parameters. IMPORTANCE: Arsenic is a major drinking water contaminant that threatens the health of millions of people worldwide. The extent of arsenic contamination and its potential threat to human health have resulted in considerable interest in the study of microbial species responsible for the reduction of arsenic, i.e., the conversion of AsV to AsIII In this study, we developed a new primer pair to evaluate the diversity and abundance of arsenate-reducing microorganisms in soil and groundwater samples from the CVB in Utah. We observed significant arrA gene diversity in the CVB soil and groundwater samples, and arrA gene abundance was significantly correlated with the reduced arsenic (AsIII) concentrations in the groundwater samples. We think that these primers are useful for studying the ecology of arsenate-reducing microorganisms in different environments.


Subject(s)
Arsenate Reductases/genetics , Arsenic/metabolism , Drinking Water/chemistry , Groundwater/chemistry , Inactivation, Metabolic/genetics , Water Pollutants, Chemical/metabolism , Arsenic/chemistry , Base Sequence , DNA Primers/genetics , Firmicutes/enzymology , Firmicutes/genetics , Firmicutes/metabolism , High-Throughput Nucleotide Sequencing , Inactivation, Metabolic/physiology , Proteobacteria/enzymology , Proteobacteria/genetics , Proteobacteria/metabolism , Soil Microbiology , Water Microbiology , Water Pollutants, Chemical/analysis
5.
J Environ Qual ; 45(5): 1490-1500, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27695739

ABSTRACT

Chemical spills and accidents contaminate the environment and disrupt societies and economies around the globe. In the United States there were approximately 172,000 chemical spills that affected US waterbodies from 2004 to 2014. More than 8000 of these spills involved non-petroleum-related chemicals. Traditional emergency responses or incident command structures (ICSs) that respond to chemical spills require coordinated efforts by predominantly government personnel from multiple disciplines, including disaster management, public health, and environmental protection. However, the requirements of emergency response teams for science support might not be met within the traditional ICS. We describe the US ICS as an example of emergency-response approaches to chemical spills and provide examples in which external scientific support from research personnel benefitted the ICS emergency response, focusing primarily on nonpetroleum chemical spills. We then propose immediate, near-term, and long-term activities to support the response to chemical spills, focusing on nonpetroleum chemical spills. Further, we call for science support for spill prevention and near-term spill-incident response and identify longer-term research needs. The development of a formal mechanism for external science support of ICS from governmental and nongovernmental scientists would benefit rapid responders, advance incident- and crisis-response science, and aid society in coping with and recovering from chemical spills.


Subject(s)
Accidents , Water Pollutants, Chemical , Hazardous Substances , United States
6.
J Environ Manage ; 166: 267-75, 2016 Jan 15.
Article in English | MEDLINE | ID: mdl-26517275

ABSTRACT

Stormwater bioretention (BR) systems collect runoff containing heavy metals, which can concentrate in soil environments and potentially leach into groundwater. This greenhouse experiment evaluated differences among six plant species undergoing three varying hydraulic and pollutant loads in their bioaccumulation potential when subjected to continual application of low metal concentrations as a means of preventing copper, lead, and zinc accumulation in the BR soil. Results show that >92% of metal mass applied to the treatments via synthetic stormwater was removed from the exfiltrate within 27 cm of soil depth. Compacted soil conditions of unplanted controls retained significantly more Cu, Pb, and Zn than Carex praegracilis, and Carex microptera treatments. Differences in above and below ground plant tissue concentrations differed among species, resulting in significant differences in mass accumulation. In the above ground tissue, from highest to lowest, Phragmites australis accumulated 8 times more Cu than Scirpus acutus, and C. microptera accumulated 18 times more Pb, and 6 times more Zn than Scirpus validus. These results, and differences among species in mass distribution of the metals recovered at the end of the study, reveal various metal accumulation mechanisms.


Subject(s)
Cyperaceae/metabolism , Metals, Heavy/metabolism , Poaceae/metabolism , Soil Pollutants/metabolism , Biodegradation, Environmental , Copper/analysis , Copper/metabolism , Lead/analysis , Lead/metabolism , Metals, Heavy/analysis , Plants , Soil/chemistry , Soil Pollutants/analysis , Water Purification/methods , Zinc/analysis , Zinc/metabolism
7.
Appl Microbiol Biotechnol ; 100(5): 2367-79, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26536878

ABSTRACT

Trichloroethene (TCE) in groundwater is a major health concern and biostimulation/bioaugmentation-based strategies have been evaluated to achieve complete reductive dechlorination with varying success. Different carbon sources were hypothesized to stimulate different extents of TCE reductive dechlorination. Ecological conditions that developed different dechlorination stages were investigated by quantitating Dehalococcoides 16S rRNA (Dhc) and reductive dehalogenase gene abundance, and by describing biogeochemical properties of laboratory columns in response to this biostimulation. Eight large columns (183 cm × 15.2 cm), packed with aquifer material from Hill AFB, Utah, that were continuously fed TCE for 7.5 years. Duplicate columns were biostimulated with whey or one of two different Newman Zone® emulsified oil formulations containing either nonionic surfactant (EOLN) or standard surfactant (EOL). Two columns were non-stimulated controls. Complete (whey amended), partial (EOLN amended), limited (EOL), and non-TCE dehalogenating systems (controls) developed over the course of the study. Bioaugmentation of half of the columns with Bachman Road culture 3 years prior to dismantling did not influence the extent of TCE dehalogenation. Multivariate analysis clustered samples by biostimulation treatments and extent of TCE dehalogenation. Dhc, tceA, and bvcA gene concentrations did not show a consistent relationship with TCE dehalogenation but the vcrA gene was more abundant in completely dehalogenating, whey-treated columns. The whey columns developed strongly reducing conditions producing Fe(II), sulfide, and methane. Biostimulation with different carbon and energy sources can support high concentrations of diverse Dhc, but carbon addition has a major influence on biogeochemical processes effecting the extent of TCE dehalogenation.


Subject(s)
Chloroflexi/metabolism , Groundwater/chemistry , Groundwater/microbiology , Trichloroethylene/metabolism , Water Pollutants, Chemical/metabolism , Water Purification/methods , Biotransformation , Chloroflexi/growth & development , Hydrolases/genetics , Oxidation-Reduction , RNA, Ribosomal, 16S/genetics , Utah
8.
Appl Environ Microbiol ; 80(10): 3198-208, 2014 May.
Article in English | MEDLINE | ID: mdl-24632255

ABSTRACT

Basin-fill aquifers of the Southwestern United States are associated with elevated concentrations of arsenic (As) in groundwater. Many private domestic wells in the Cache Valley Basin, UT, have As concentrations in excess of the U.S. EPA drinking water limit. Thirteen sediment cores were collected from the center of the valley at the depth of the shallow groundwater and were sectioned into layers based on redoxmorphic features. Three of the layers, two from redox transition zones and one from a depletion zone, were used to establish microcosms. Microcosms were treated with groundwater (GW) or groundwater plus glucose (GW+G) to investigate the extent of As reduction in relation to iron (Fe) transformation and characterize the microbial community structure and function by sequencing 16S rRNA and arsenate dissimilatory reductase (arrA) genes. Under the carbon-limited conditions of the GW treatment, As reduction was independent of Fe reduction, despite the abundance of sequences related to Geobacter and Shewanella, genera that include a variety of dissimilatory iron-reducing bacteria. The addition of glucose, an electron donor and carbon source, caused substantial shifts toward domination of the bacterial community by Clostridium-related organisms, and As reduction was correlated with Fe reduction for the sediments from the redox transition zone. The arrA gene sequencing from microcosms at day 54 of incubation showed the presence of 14 unique phylotypes, none of which were related to any previously described arrA gene sequence, suggesting a unique community of dissimilatory arsenate-respiring bacteria in the Cache Valley Basin.


Subject(s)
Arsenic/metabolism , Bacteria/genetics , Bacteria/metabolism , Geologic Sediments/microbiology , Groundwater/microbiology , Iron/metabolism , Bacteria/classification , Bacteria/isolation & purification , Biodiversity , Biotransformation , Molecular Sequence Data , Oxidation-Reduction , Phylogeny , Utah , Water Supply/analysis
9.
J Contam Hydrol ; 150: 45-53, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23673086

ABSTRACT

Aerobic biotransformation of N-nitrosodimethylamine (NDMA), an emerging contaminant of concern, and its structural analog N-nitrodimethylamine (DMN), was evaluated in benzene and methane amended groundwater passed through laboratory scale soil columns. Competitive inhibition models were used to model the kinetics for NDMA and DMN cometabolism accounting for the concurrent degradation of the growth and cometabolic substrates. Transformation capacities for NDMA and DMN with benzene (13 and 23µg (mgcells)(-1)) and methane (0.14 and 8.4µg (mgcells)(-1)) grown cultures, respectively are comparable to those presented in the literature, as were first order endogenous decay rates estimated to be 2.1×10(-2)±1.7×10(-3)d(-1) and 6.5×10(-1)±7.1×10(-1)d(-1) for the methane and benzene amended cultures, respectively. These studies highlight possible attenuation mechanisms and rates for NDMA and DMN biotransformation in aerobic aquifers undergoing active remediation, natural attenuation or managed aquifer recharge with treated wastewater (i.e., reclaimed water).


Subject(s)
Benzene/metabolism , Dimethylamines/metabolism , Dimethylnitrosamine/metabolism , Methane/metabolism , Water Pollutants, Chemical/metabolism , Aerobiosis , Bacteria/metabolism , Biodegradation, Environmental , Groundwater , Models, Theoretical , Soil
10.
Mol Psychiatry ; 13(4): 407-16, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17579606

ABSTRACT

Previously, we reported a genome-wide scan for nicotine dependence (ND) in the African American (AA) sample of the Mid-South Tobacco Family (MSTF) cohort. In this study, we conducted a genome-wide scan in 629 individuals representing 200 nuclear families of European American (EA) origin of the MSTF cohort with the goals of identifying vulnerability loci for ND in the EAs and determining converging regions across the ethnic groups. We examined 385 autosomal microsatellite markers for ND, which was assessed by smoking quantity (SQ), the Heaviness of Smoking Index (HSI) and the Fagerström test for ND (FTND). After performing linkage analyses using various methods implemented in the GENEHUNTER and SAGE programs, we found eight regions on chromosomes 2, 4, 9-12, 17 and 18 that met the criteria for suggestive linkage to at least one ND measure in the EA sample. Of these, the region on chromosome 4 at 43 cM showed suggestive linkage to indexed SQ, the HSI and the FTND, and the region on chromosome 9 at 24 cM showed suggestive linkage to the HSI and the FTND. To increase detection power, we analyzed a combined AA and EA sample using age, gender and ethnicity as covariates and found that the region on chromosome 12 near marker D12S372 showed significant linkage to SQ. Additionally, we found six regions on chromosomes 9-11, 13 and 18 that showed suggestive linkage to at least one ND measure in the combined sample. When we compared the linkage peaks detected for ND among the two samples and a combined sample, we found that four regions on chromosomes 9 (two regions), 11 and 18 overlapped. On the other hand, we identified five regions on chromosomes 2, 4, 10, 12 and 17 that showed linkage to ND only in the EA sample, and two regions on chromosomes 10 and 13 that showed linkage to ND only in the AA sample. For those linkages identified in only one sample, we found that the combined analysis of AA plus EA samples actually decreased the linkage signal. This indicates that some chromosomal regions may be more homogenous than others across the ethnic samples. All regions except for the one on chromosome 12 have been detected at nominally significant levels in other studies, providing independent replication of ND loci in different populations.


Subject(s)
Family Health , Genetic Predisposition to Disease , Genome, Human , Linkage Disequilibrium/genetics , Polymorphism, Single Nucleotide , Tobacco Use Disorder/genetics , Adult , Black or African American , Chromosome Mapping , Cohort Studies , Female , Gene Frequency , Genotype , Humans , Male , Middle Aged , Phenotype , Retrospective Studies , Smoking , Tobacco Use Disorder/blood , White People
11.
J Environ Qual ; 35(4): 1193-203, 2006.
Article in English | MEDLINE | ID: mdl-16825439

ABSTRACT

Biostimulation has been used at various contaminated sites to promote the reductive dechlorination of trichloroethylene (TCE), but the addition of carbon and energy donor also stimulates bacteria that use Fe(III) as the terminal electron acceptor (TEA) in potential competition with dechlorination processes. Microcosm studies were conducted to determine the influence of various carbon donors on the extent of reductive dissolution of aquifer solids containing Fe(III) and arsenic. Glucose, a fermentable and respirable carbon donor, led to the production of 1500 mg Fe(II) kg(-1), or 24% of the total Fe in the aquifer sediment being reduced to Fe(II), whereas the same concentration of carbon as acetate resulted in only 300 mg Fe(II) kg(-1) being produced. The biogenic Fe(II) produced with acetate was exclusively associated with the solid phase whereas with fermentable carbon donors as whey and glucose, 22 and 54% of the Fe(II) was in solution. With fermentation, some of the metabolites appear to be electron shuttling chemicals and chelating agents that facilitate the reductive dissolution of even crystalline Fe(III) oxides. Without the presence of electron shuttling chemicals, only surficial Fe in direct contact with the bacteria was bioavailable, as illustrated when acetate was used. Regardless of carbon donor type and concentration, As concentrations in the water exceeded drinking water standards. The As dissolution appears to have been the result of the direct use of As as an electron acceptor by dissimilatory arsenic reducing bacteria. Our findings indicate that selection of the carbon and energy donor for biostimulation for remediation of chlorinated solvent impacted aquifers may greatly influence the extent of the reductive dissolution of iron minerals in direct competition with dechlorination processes. Biostimulation may also result in a significant release of As to the solution phase, contributing to further contamination of the aquifer.


Subject(s)
Arsenic/metabolism , Iron/metabolism , Soil Microbiology , Soil Pollutants/metabolism , Water Pollutants/metabolism , Acetates/analysis , Acetates/chemistry , Arsenic/analysis , Biodegradation, Environmental , Biological Availability , Carbon/analysis , Carbon/metabolism , Chelating Agents/chemistry , Fermentation , Ferric Compounds/analysis , Ferric Compounds/metabolism , Ferrous Compounds/analysis , Ferrous Compounds/metabolism , Glucose/metabolism , Iron/analysis , Soil Pollutants/analysis , Water Pollutants/analysis , Water Purification/methods
12.
J Hazard Mater ; 98(1-3): 127-44, 2003 Mar 17.
Article in English | MEDLINE | ID: mdl-12628782

ABSTRACT

Field-scale tracer studies were conducted at a gasoline-contaminated site in order to evaluate the effectiveness of in situ air sparging (IAS) and in-well aeration (IWA) in controlling the movement of soil gas and groundwater in the subsurface. The field site was comprised of silty sand (SM) and silty clay (CL), underlain by a clay layer at approximately 7.6 m. Depth to groundwater ranged from 2.4 to 3 m. Soil permeability and the natural hydraulic gradient were both low. Helium was used to trace the movement of soil gas in the unsaturated zone during the IAS field study, and successfully confirmed short-circuit pathways for injected air and demonstrated the limited distribution of injected gases at this site. Fluorescein, bromide, and rhodamine were used to trace the movement of groundwater during the IWA system field study, and successfully documented the inability of the IWA system to recirculate enough groundwater to enhance subsurface dissolved oxygen levels or to remediate groundwater by air stripping at this site. The inability of the systems to remediate the site was likely due to site conditions which consist of low-permeability soils and decreasing permeability with depth. As a result, relatively impermeable layers exist at the depth of the IAS screen and the lower IWA screen. These site conditions are not conducive to successful performance of either remediation system.


Subject(s)
Gasoline/analysis , Soil Pollutants/analysis , Water Movements , Water Pollutants, Chemical/analysis , Biodegradation, Environmental , Environmental Pollution/prevention & control , Organic Chemicals/analysis , Permeability
13.
Article in English | MEDLINE | ID: mdl-12046644

ABSTRACT

Results of a five-year research study on natural attenuation processes in a wetland, located downgradient of a sour gas processing plant in central Alberta, Canada, show that natural attenuation may present a favourable remedial solution. Both free-phase and dissolved phase condensate have been discharging to the wetland since 1984. This condensate is primarily composed of C5 to C12 hydrocarbons, including BTEX compounds. The condensate enters the base of the wetland at 1 m below ground surface, resulting in contamination of the wetland peat and underlying clay till. The lateral extent of contamination in the wetland has remained stable, and apparent free product thickness and BTEX concentrations have decreased over time. Sorption, aerobic biodegradation, volatilization, and anaerobic biodegradation were identified as active attenuation processes at this site. Sorption and desorption processes were evaluated by laboratory testing of site soils using 14C-benzene. Linear sorption coefficients (Kd) for the surface and subsurface peat were similar (4.48-4.62 l/kg), while the Kd for the underlying silt was 0.096 l/kg. The significantly higher Kd values for the peat are attributed to the peat's higher organic content (40%), relative to the clayey silt (1%). No significant resistance to desorption was observed, however, indicating that benzene would remain mobile and bioavailable over time. Aerobic biodegradation and volatilization appear to be the main removal processes. They are enhanced by a seasonal drop in the water level from surface down to 1 m depth, resulting in an aerobic unsaturated zone. Respiration testing in the peat indicates a significant aerobic biodegradation rate of 27 mg/kg/day, equating to an estimated hydrocarbon removal rate of 5 kg/day across the 3600 m2 plume area. Surface vapour measurements indicate hydrocarbon volatilization is occurring at a rate of 3 x 10(-4) kg/m2/day, equating to a mass removal of 1 kg/day across the plume. Anaerobic biodegradation is occurring primarily in the clayey silt, based on geochemical indicator parameters, microbial analyses, and soil vapour sampling. Overall, natural attenuation appears to be a feasible remedial solution for this wetland, by providing continued removal and degradation of condensate components before they reach the downgradient surface water receptor.


Subject(s)
Ecosystem , Hydrocarbons/metabolism , Adsorption , Aluminum Silicates , Bacteria, Aerobic , Biodegradation, Environmental , Clay , Conservation of Natural Resources , Gases , Volatilization
14.
Water Sci Technol ; 45(3): 95-100, 2002.
Article in English | MEDLINE | ID: mdl-11902485

ABSTRACT

The sewer system for the Greater Copenhagen area covers an area of 4460 ha contributing to the runoff. The total area serves in total 8 municipalities, however it is dominated by the areas in the City of Copenhagen proper. The catchments merge into interceptors, which feed two large treatment plants. The effluent from the two treatment plants discharges during dry weather to Oresund, the sound between Denmark and Sweden. This large system has been analysed for selected scenarios with respect to handling runoff in an optimal way in order to minimise the loads on the most sensitive receiving waters and optimising treatment plant performance.


Subject(s)
Environment , Sewage , Waste Disposal, Fluid , Cities , Denmark , Forecasting , Water Movements , Water Supply , Weather
15.
Bioorg Med Chem Lett ; 11(24): 3175-8, 2001 Dec 17.
Article in English | MEDLINE | ID: mdl-11720868

ABSTRACT

Fourteen catechol and bis-catechol derivatives have been synthesised and tested for their HIV-1 inhibitory activities. The six more active molecules have been tested for their antiviral activity and cytotoxicity. We have found that bis-catechols 1 and 2 are the most active HIV-1 integrase inhibitor whereas the best antiviral compound is 4.


Subject(s)
Catechols/chemical synthesis , Catechols/pharmacology , HIV Integrase Inhibitors/chemical synthesis , HIV Integrase Inhibitors/pharmacology , Cell Line , HIV-1/drug effects , HIV-1/enzymology , Humans , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Virus Replication/drug effects
16.
J Med Pract Manage ; 16(6): 306-8, 2001.
Article in English | MEDLINE | ID: mdl-11497311

ABSTRACT

Recruitment is no longer just a face-to-face interaction between a recruiter and a job-seeker. To remain up-to-date with current technology, physicians should use the various electronic tools available today, including recruitment websites, video previews, and PC-to-PC interviews to get the job they've been looking for. This article discusses the pros and cons of these interfaces.


Subject(s)
Internet , Personnel Selection/methods , Physicians , Education, Distance , Information Services , Interviews as Topic , Job Application , Physicians/supply & distribution , United States
17.
Int J Neuropsychopharmacol ; 4(2): 105-12, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11466158

ABSTRACT

Although abuse of cocaine or methamphetamine usually takes place in the context of heavy drinking, there is little information on the effects of such substance use comorbidity on brain perfusion. We explored similarities and differences in the effects of these two drugs in combination with alcohol on brain function using SPECT. Global and regional cerebral blood flow (CBF) were examined in 7 abstinent cocaine-dependent alcoholics (CDA; mean age = 39.2 yr, S.D. = 9.2 yr), 7 abstinent methamphetamine-dependent alcoholics (MDA; mean age = 36.8 yr, S.D. = 5.0 yr), and 7 non-alcoholic/non-stimulant abusing controls (NAC; mean age = 37.3 yr, S.D. = 9.6 yr). MDA had significantly lower global CBF than CDA who, in turn, were significantly lower than NAC. In addition, CDA had abnormal perfusion in the superior posterior frontal region compared to NAC; while MDA did not display specific regional deficits. Therefore, it appears that cocaine alters the relationship between global and regional CBF in alcoholics, while methamphetamine does not.


Subject(s)
Alcoholism/physiopathology , Cerebral Cortex/blood supply , Cerebrovascular Circulation , Cocaine-Related Disorders/physiopathology , Methamphetamine , Substance-Related Disorders/physiopathology , Adult , Alcoholism/complications , Alcoholism/diagnostic imaging , Cerebral Cortex/diagnostic imaging , Cocaine-Related Disorders/complications , Cocaine-Related Disorders/diagnostic imaging , Female , Humans , Image Interpretation, Computer-Assisted , Male , Middle Aged , Radiopharmaceuticals , Substance-Related Disorders/complications , Substance-Related Disorders/diagnostic imaging , Technetium Tc 99m Exametazime , Tomography, Emission-Computed, Single-Photon/methods
18.
J Med Pract Manage ; 16(5): 266-8, 2001.
Article in English | MEDLINE | ID: mdl-11345887

ABSTRACT

Searching for the ideal job can be a difficult task. The challenge is often made more difficult when candidates use the Internet without the background information they need. This article discusses the four categories of physician recruitment websites (Association Directories, Journal Classified Ads, Recruiting Firms/Departments, and Database Clearinghouses) and lists several useful URLs to visit as you begin your search. In an upcoming issue, the author will address the future of physician recruitment websites.


Subject(s)
Internet , Personnel Selection , Physicians/supply & distribution , Humans
19.
Bioorg Med Chem ; 9(2): 229-35, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11249115

ABSTRACT

Three polyhydroxy-2-phenylnaphthalenes (1-3) and the oxy analogue of tetrahydroxypavinan (4) were prepared and evaluated for their antioxidant properties (inhibition of diphenylpycrylhydrazyl radical (DPPH), reduction of iron (III) ion) and inhibition of 5-lipoxygenase (5-LO) activity. Their three-dimensional structures were established on the basis of spectroscopic data and semiempirical calculations. Compounds 1 and 2 were found as potent 5-LO inhibitors as nordihydroguaiaretic acid (NDGA), whereas 4 is 2.5 times less potent than NDGA. The reliability of the 3-D structures with the 5-LO inhibition properties is discussed. Their antioxidant properties show that tested compounds are expected to act as redox inhibitors.


Subject(s)
Arachidonate 5-Lipoxygenase/drug effects , Bepridil/analogs & derivatives , Lipoxygenase Inhibitors/chemical synthesis , Picrates , Animals , Antioxidants/chemical synthesis , Antioxidants/pharmacology , Arachidonate 5-Lipoxygenase/metabolism , Bepridil/metabolism , Biphenyl Compounds , Catechols , Indicators and Reagents , Iron/metabolism , Kinetics , Lipoxygenase Inhibitors/pharmacology , Molecular Structure , Oxidation-Reduction , Rats , Structure-Activity Relationship , Tumor Cells, Cultured
20.
J Hazard Mater ; 82(2): 197-212, 2001 Mar 30.
Article in English | MEDLINE | ID: mdl-11230915

ABSTRACT

Several in-well aeration (IWA) technologies have been used since the early 1990s, but few field studies have been performed to evaluate the extent of water circulation around IWA systems. In this study, 27 discrete monitoring points (MPs) were installed at a gasoline-contaminated site to assess the efficacy of IWA. Pressure transducers and dissolved oxygen (DO) probes were sealed into the MPs, allowing them to be used to characterize subsurface changes in total head and DO with depth, distance and orientation from a central injection well. No change in DO or in hydrocarbon total mass or distribution occurred across the site during two trials (41 and 20 days) of the system. Water level fluctuations during the trials were similar in all MPs, and were due to seasonal water table changes and rainfall events. No circulation cell was established around the IWA well after 41 days of operation, and the impact of the well extended less than 90cm from it. Groundwater only circulated through the sand pack around the well. Little, if any, recharge occurred through the lower screen. Silt accumulated in the well, limiting its operation time, even with a fabric filter sock over the lower screen. Obviously, IWA was ineffective at this site, probably because the horizontal hydraulic conductivity (K(h)) of the soil opposite the lower screen was low (0.09cm per day) and because the distance between the two screens was short relative to the borehole radius. Long remediation times would likely make IWA unattractive at this or other sites where the K(h) of the soil is so low that the air injection rate would have to be low to prevent blowing the well dry.


Subject(s)
Environmental Monitoring , Hydrocarbons/analysis , Soil Pollutants/analysis , Water Supply , Biodegradation, Environmental , Hydrocarbons/pharmacokinetics , Oxygen/analysis , Soil Pollutants/pharmacokinetics , Water Movements
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