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1.
Environ Sci Technol ; 54(13): 8380-8389, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32432863

RESUMO

Polychlorinated dibenzo-p-dioxins (PCDDs) are a class of toxic organic compounds released by a number of industrial processes. Sediments of the Passaic River in New Jersey are contaminated by these compounds. To explore the ability of native organohalide respiring bacteria to dechlorinate PCDDs, we first enriched bacteria from sediments of the Passaic River on two organohalides, trichloroethene (TCE) and 1,2-dichlorobenzene (DCB). We then used these enriched sediment cultures and original, unamended sediment as the inocula in a secondary experiment with 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TeCDD), 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TeCDD), and 2,7-dichlorodibenzo-p-dioxin (2,7-DiCDD) as target organohalides. We observed dechlorination of 1,2,3,4-TeCDD by all inocula, although to different extents. We observed progressive dechlorination of 2,3,7,8-TeCDD only in bottles inoculated with the DCB enrichment culture, and dechlorination of 2,7-DiCDD almost exclusively in bottles inoculated with the original, unamended river sediment. Dechlorination of 1,2,3,4-TeCDD was more rapid than that of the other amended congeners. Phylotypes within the class Dehalococcoidia associated with organohalide dechlorination were differentially enriched in DCB versus TCE enrichment cultures, indicating that they may play a role in dechlorination of the PCDDs.


Assuntos
Chloroflexi , Dibenzodioxinas Policloradas , Bactérias , Sedimentos Geológicos , New Jersey , Rios
2.
Proc Natl Acad Sci U S A ; 114(44): E9206-E9215, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29078310

RESUMO

The past decade of scientific ocean drilling has revealed seemingly ubiquitous, slow-growing microbial life within a range of deep biosphere habitats. Integrated Ocean Drilling Program Expedition 337 expanded these studies by successfully coring Miocene-aged coal beds 2 km below the seafloor hypothesized to be "hot spots" for microbial life. To characterize the activity of coal-associated microorganisms from this site, a series of stable isotope probing (SIP) experiments were conducted using intact pieces of coal and overlying shale incubated at in situ temperatures (45 °C). The 30-month SIP incubations were amended with deuterated water as a passive tracer for growth and different combinations of 13C- or 15N-labeled methanol, methylamine, and ammonium added at low (micromolar) concentrations to investigate methylotrophy in the deep subseafloor biosphere. Although the cell densities were low (50-2,000 cells per cubic centimeter), bulk geochemical measurements and single-cell-targeted nanometer-scale secondary ion mass spectrometry demonstrated active metabolism of methylated substrates by the thermally adapted microbial assemblage, with differing substrate utilization profiles between coal and shale incubations. The conversion of labeled methylamine and methanol was predominantly through heterotrophic processes, with only minor stimulation of methanogenesis. These findings were consistent with in situ and incubation 16S rRNA gene surveys. Microbial growth estimates in the incubations ranged from several months to over 100 y, representing some of the slowest direct measurements of environmental microbial biosynthesis rates. Collectively, these data highlight a small, but viable, deep coal bed biosphere characterized by extremely slow-growing heterotrophs that can utilize a diverse range of carbon and nitrogen substrates.


Assuntos
Organismos Aquáticos/crescimento & desenvolvimento , Carvão Mineral/microbiologia , Sedimentos Geológicos/microbiologia , Metanol/metabolismo , Metilaminas/metabolismo , Água do Mar/microbiologia , Biomassa , Ecossistema , Isótopos/metabolismo , Espectrometria de Massa de Íon Secundário/métodos
3.
Environ Microbiol ; 20(12): 4281-4296, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29968367

RESUMO

Nitrogen fixation, the biological conversion of N2 to NH3 , is critical to alleviating nitrogen limitation in many marine ecosystems. To date, few measurements exist of N2 fixation in deep-sea sediments. Here, we conducted > 400 bottle incubations with sediments from methane seeps, whale falls and background sites off the western coast of the United States from 600 to 2893 m water depth to investigate the potential rates, spatial distribution and biological mediators of benthic N2 fixation. We found that N2 fixation was widespread, yet heterogeneously distributed with sediment depth at all sites. In some locations, rates exceeded previous measurements by > 10×, and provided up to 30% of the community anabolic growth requirement for nitrogen. Diazotrophic activity appeared to be inhibited by pore water ammonium: N2 fixation was only observed if incubation ammonium concentrations were ≤ 25 µM, and experimental additions of ammonium reduced diazotrophy. In seep sediments, N2 fixation was dependent on CH4 and coincident with sulphate reduction, consistent with previous work showing diazotrophy by microorganisms mediating sulphate-coupled methane oxidation. However, the pattern of diazotrophy was different in whale-fall and associated reference sediments, where it was largely unaffected by CH4 , suggesting catabolically different diazotrophs at these sites.


Assuntos
Bactérias/metabolismo , Carbono/química , Carbono/metabolismo , Sedimentos Geológicos/microbiologia , Fixação de Nitrogênio/fisiologia , Compostos de Amônio , Ecossistema , Metano , Nitrogênio , Oceano Pacífico , Água do Mar , Microbiologia do Solo
4.
Mult Scler ; 23(14): 1875-1883, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28156185

RESUMO

BACKGROUND: Delayed-release dimethyl fumarate (DMF) is an approved oral treatment for relapsing forms of multiple sclerosis (MS). Preclinical studies demonstrated that DMF activated the nuclear factor E2-related factor 2 (Nrf2) pathway. DMF and its primary metabolite monomethyl fumarate (MMF) were also shown to promote cytoprotection of cultured central nervous system (CNS) cells via the Nrf2 pathway. OBJECTIVE: To investigate the activation of Nrf2 pathway following ex vivo stimulation of human peripheral blood mononuclear cells (PBMCs) with DMF or MMF, and in DMF-treated patients from two Phase 3 relapsing MS studies DEFINE and CONFIRM. METHODS: Transcription of Nrf2 target genes NADPH:quinone oxidoreductase-1 (NQO1) and heme-oxygenase-1 (HO1) was measured using Taqman® assays. RNA samples were isolated from ex vivo-stimulated PBMCs and from whole blood samples of 200 patients each from placebo, twice daily (BID) and three times daily (TID) treatments. RESULTS: DMF and MMF induced NQO1 and HO1 gene expression in ex vivo-stimulated PBMCs, DMF being the more potent inducer. Induction of NQO1 occurred at lower DMF concentrations compared to that of HO1. In DMF-treated patients, a statistically significant induction of NQO1 was observed relative to baseline and compared to placebo. No statistical significance was reached for HO1 induction. CONCLUSION: These data provide the first evidence of Nrf2 pathway activation from two large pivotal Phase 3 studies of DMF-treated MS patients.


Assuntos
Fumaratos/farmacologia , Heme Oxigenase-1/efeitos dos fármacos , Imunossupressores/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , NAD(P)H Desidrogenase (Quinona)/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Adulto , Preparações de Ação Retardada , Fumarato de Dimetilo/administração & dosagem , Fumarato de Dimetilo/farmacologia , Feminino , Fumaratos/administração & dosagem , Humanos , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente
5.
Rapid Commun Mass Spectrom ; 31(9): 791-803, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28249106

RESUMO

RATIONALE: Dissolved sulfur species are of significant interest, both as important substrates for microbial activities and as key intermediaries in biogeochemical cycles. Species of intermediate oxidation state such as sulfite, thiosulfate, and thiols are of particular interest but are notoriously difficult to analyze, because of low concentrations and rapid oxidation during storage and analysis. METHODS: Dissolved sulfur species are reacted with monobromobimane which yields a fluorescent bimane derivative that is stable to oxidation. Separation by Ultra-Performance Liquid Chromatography (UPLC) on a C18 column yields baseline resolution of analytes in under 5 min. Fluorescence detection (380 nm excitation, 480 nm emission) provides highly selective and sensitive quantitation, and Time-of-Flight Mass Spectrometry (TOF-MS) is used to quantify isotopic abundance, providing the ability to detect stable isotope tracers (either 33 S or 34 S). RESULTS: Sulfite, thiosulfate, methanethiol, and bisulfide were quantified with on-column detection limits of picomoles (µM concentrations). Other sulfur species with unshared electrons are also amenable to analysis. TOF-MS detection of 34 S enrichment was accurate and precise to within 0.6% (relative) when sample and standard had similar isotope ratios, and was able to detect enrichments as small as 0.01 atom%. Accuracy was validated by comparison to isotope-ratio mass spectrometry. Four example applications are provided to demonstrate the utility of this method. CONCLUSIONS: Derivatization of aqueous sulfur species with bromobimane is easily accomplished in the field, and protects analytes from oxidation during storage. UPLC separation with fluorescence detection provides low-µM detection limits. Using high-resolution TOF-MS, accurate detection of as little as 0.01% 34 S label incorporation into multiple species is feasible. This provides a useful new analytical window into microbial sulfur cycling. Copyright © 2017 John Wiley & Sons, Ltd.

6.
Br J Clin Pharmacol ; 82(2): 380-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27060836

RESUMO

AIM: Subcutaneous (s.c.) peginterferon beta-1a injected once every 2 weeks and s.c. interferon beta-1a injected three times per week (Rebif®) have demonstrated efficacy in relapsing-remitting multiple sclerosis, but direct comparisons of pharmacological activity and tolerability between the two products are lacking. COMPARE was an open label, crossover, pharmacokinetic (PK) study evaluating drug exposure and the safety and tolerability of s.c. peginterferon beta-1a and s.c. interferon beta-1a, over 2 weeks in healthy subjects. METHODS: Thirty healthy subjects received one dose of peginterferon beta-1a (125 µg s.c.) or six doses of interferon beta-1a (44 µg s.c.) over 2 weeks, followed by the alternate treatment after a 2 week washout period. Drug concentrations were measured using an enzyme-linked immunosorbent assay (ELISA) and PK parameters including cumulative area under the concentration-time curve (AUC0-336h ) over 2 weeks and maximum observed serum concentrations (Cmax ) were estimated using a non-compartmental analysis. RESULTS: The PK analysis population comprised 26 subjects for each treatment. Drug exposure (AUC0-336h ) was 60% higher with s.c. peginterferon than with s.c. interferon beta-1a (117.4 ng ml(-1) h, 95% confidence interval 95.6, 144.3 vs. 73.1 ng ml(-1) h, 95% confidence interval 61.2, 87.3, respectively; P < 0.0001). Injection-site reactions (ISRs) were the most common adverse events (AEs) observed with both treatments. Numerically lower frequencies and incidence rates of ISRs, headache, myalgia and chills were observed with s.c. peginterferon beta-1a. CONCLUSIONS: One dose of s.c. peginterferon delivered significantly greater drug exposure than s.c. interferon beta-1a three times a week over 2 weeks, and a lower frequency of AEs.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Interferon beta-1a/administração & dosagem , Interferon beta/administração & dosagem , Polietilenoglicóis/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , Adjuvantes Imunológicos/farmacocinética , Adolescente , Adulto , Área Sob a Curva , Estudos Cross-Over , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Injeções Subcutâneas , Interferon beta-1a/efeitos adversos , Interferon beta-1a/farmacocinética , Interferon beta/efeitos adversos , Interferon beta/farmacocinética , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/farmacocinética , Adulto Jovem
7.
J Acoust Soc Am ; 139(5): EL167, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27250203

RESUMO

Optical marker tracking integrated with electromagnetic articulometry was used to assess the movement extent of various points on (a) forehead skin and (b) points on a head-mounted apparatus, relative to a fixed point just above the upper incisors, and to compare the accuracy of the two different approaches to indexing head position during speech production. Both methods can provide a satisfactory index of head position. If skin-affixed markers are used, a minimum of 4 is recommended. Locations for optimal marker placement are identified.


Assuntos
Fenômenos Eletromagnéticos , Movimentos da Cabeça , Cabeça/fisiologia , Óptica e Fotônica/instrumentação , Fala , Transdutores , Voz , Adulto , Pontos de Referência Anatômicos , Desenho de Equipamento , Feminino , Cabeça/anatomia & histologia , Humanos , Interpretação de Imagem Assistida por Computador , Raios Infravermelhos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
8.
Clin Linguist Phon ; 30(3-5): 328-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26587871

RESUMO

Quantification of tongue shape is potentially useful for indexing articulatory strategies arising from intervention, therapy and development. Tongue shape complexity is a parameter that can be used to reflect regional functional independence of the tongue musculature. This paper considers three different shape quantification methods - based on Procrustes analysis, curvature inflections and Fourier coefficients - and uses a linear discriminant analysis to test how well each method is able to classify tongue shapes from different phonemes. Test data are taken from six native speakers of American English producing 15 phoneme types. Results classify tongue shapes accurately when combined across quantification methods. These methods hold promise for extending the use of ultrasound in clinical assessments of speech deficits.


Assuntos
Fonética , Fala/fisiologia , Língua/anatomia & histologia , Ultrassonografia , Adulto , Humanos , Pessoa de Meia-Idade , Medida da Produção da Fala/métodos , Língua/diagnóstico por imagem
9.
N Engl J Med ; 367(12): 1087-97, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22992072

RESUMO

BACKGROUND: BG-12 (dimethyl fumarate) is in development as an oral treatment for relapsing-remitting multiple sclerosis, which is commonly treated with parenteral agents (interferon or glatiramer acetate). METHODS: In this phase 3, randomized study, we investigated the efficacy and safety of oral BG-12, at a dose of 240 mg two or three times daily, as compared with placebo in patients with relapsing-remitting multiple sclerosis. An active agent, glatiramer acetate, was also included as a reference comparator. The primary end point was the annualized relapse rate over a period of 2 years. The study was not designed to test the superiority or noninferiority of BG-12 versus glatiramer acetate. RESULTS: At 2 years, the annualized relapse rate was significantly lower with twice-daily BG-12 (0.22), thrice-daily BG-12 (0.20), and glatiramer acetate (0.29) than with placebo (0.40) (relative reductions: twice-daily BG-12, 44%, P<0.001; thrice-daily BG-12, 51%, P<0.001; glatiramer acetate, 29%, P=0.01). Reductions in disability progression with twice-daily BG-12, thrice-daily BG-12, and glatiramer acetate versus placebo (21%, 24%, and 7%, respectively) were not significant. As compared with placebo, twice-daily BG-12, thrice-daily BG-12, and glatiramer acetate significantly reduced the numbers of new or enlarging T(2)-weighted hyperintense lesions (all P<0.001) and new T(1)-weighted hypointense lesions (P<0.001, P<0.001, and P=0.002, respectively). In post hoc comparisons of BG-12 versus glatiramer acetate, differences were not significant except for the annualized relapse rate (thrice-daily BG-12), new or enlarging T(2)-weighted hyperintense lesions (both BG-12 doses), and new T(1)-weighted hypointense lesions (thrice-daily BG-12) (nominal P<0.05 for each comparison). Adverse events occurring at a higher incidence with an active treatment than with placebo included flushing and gastrointestinal events (with BG-12) and injection-related events (with glatiramer acetate). There were no malignant neoplasms or opportunistic infections reported with BG-12. Lymphocyte counts decreased with BG-12. CONCLUSIONS: In patients with relapsing-remitting multiple sclerosis, BG-12 (at both doses) and glatiramer acetate significantly reduced relapse rates and improved neuroradiologic outcomes relative to placebo. (Funded by Biogen Idec; CONFIRM ClinicalTrials.gov number, NCT00451451.).


Assuntos
Fumaratos/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Peptídeos/uso terapêutico , Administração Oral , Adulto , Encéfalo/patologia , Fumarato de Dimetilo , Método Duplo-Cego , Feminino , Fumaratos/administração & dosagem , Fumaratos/efeitos adversos , Acetato de Glatiramer , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Infecções/etiologia , Análise de Intenção de Tratamento , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/patologia , Peptídeos/efeitos adversos
10.
N Engl J Med ; 367(12): 1098-107, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22992073

RESUMO

BACKGROUND: BG-12 (dimethyl fumarate) was shown to have antiinflammatory and cytoprotective properties in preclinical experiments and to result in significant reductions in disease activity on magnetic resonance imaging (MRI) in a phase 2, placebo-controlled study involving patients with relapsing-remitting multiple sclerosis. METHODS: We conducted a randomized, double-blind, placebo-controlled phase 3 study involving patients with relapsing-remitting multiple sclerosis. Patients were randomly assigned to receive oral BG-12 at a dose of 240 mg twice daily, BG-12 at a dose of 240 mg three times daily, or placebo. The primary end point was the proportion of patients who had a relapse by 2 years. Other end points included the annualized relapse rate, the time to confirmed progression of disability, and findings on MRI. RESULTS: The estimated proportion of patients who had a relapse was significantly lower in the two BG-12 groups than in the placebo group (27% with BG-12 twice daily and 26% with BG-12 thrice daily vs. 46% with placebo, P<0.001 for both comparisons). The annualized relapse rate at 2 years was 0.17 in the twice-daily BG-12 group and 0.19 in the thrice-daily BG-12 group, as compared with 0.36 in the placebo group, representing relative reductions of 53% and 48% with the two BG-12 regimens, respectively (P<0.001 for the comparison of each BG-12 regimen with placebo). The estimated proportion of patients with confirmed progression of disability was 16% in the twice-daily BG-12 group, 18% in the thrice-daily BG-12 group, and 27% in the placebo group, with significant relative risk reductions of 38% with BG-12 twice daily (P=0.005) and 34% with BG-12 thrice daily (P=0.01). BG-12 also significantly reduced the number of gadolinium-enhancing lesions and of new or enlarging T(2)-weighted hyperintense lesions (P<0.001 for the comparison of each BG-12 regimen with placebo). Adverse events associated with BG-12 included flushing and gastrointestinal events, such as diarrhea, nausea, and upper abdominal pain, as well as decreased lymphocyte counts and elevated liver aminotransferase levels. CONCLUSIONS: In patients with relapsing-remitting multiple sclerosis, both BG-12 regimens, as compared with placebo, significantly reduced the proportion of patients who had a relapse, the annualized relapse rate, the rate of disability progression, and the number of lesions on MRI. (Funded by Biogen Idec; DEFINE ClinicalTrials.gov number, NCT00420212.).


Assuntos
Fumaratos/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Administração Oral , Adulto , Encéfalo/patologia , Fumarato de Dimetilo , Método Duplo-Cego , Feminino , Fumaratos/administração & dosagem , Fumaratos/efeitos adversos , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Infecções/etiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/patologia
11.
Int J Syst Evol Microbiol ; 65(Pt 1): 251-259, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25342114

RESUMO

We report the isolation and growth characteristics of a gammaproteobacterial methane-oxidizing bacterium (Methylococcaceae strain WF1(T), 'whale fall 1') that shares 98 % 16S rRNA gene sequence identity with uncultivated free-living methanotrophs and the methanotrophic endosymbionts of deep-sea mussels, ≤94.6 % 16S rRNA gene sequence identity with species of the genus Methylobacter and ≤93.6 % 16S rRNA gene sequence identity with species of the genera Methylomonas and Methylosarcina. Strain WF1(T) represents the first cultivar from the 'deep sea-1' clade of marine methanotrophs, which includes members that participate in methane oxidation in sediments and the water column in addition to mussel endosymbionts. Cells of strain WF1(T) were elongated cocci, approximately 1.5 µm in diameter, and occurred singly, in pairs and in clumps. The cell wall was Gram-negative, and stacked intracytoplasmic membranes and storage granules were evident. The genomic DNA G+C content of WF1(T) was 40.5 mol%, significantly lower than that of currently described cultivars, and the major fatty acids were 16 : 0, 16 : 1ω9c, 16 : 1ω9t, 16 : 1ω8c and 16 : 2ω9,14. Growth occurred in liquid media at an optimal temperature of 23 °C, and was dependent on the presence of methane or methanol. Atmospheric nitrogen could serve as the sole nitrogen source for WF1(T), a capacity that had not been functionally demonstrated previously in members of Methylobacter. On the basis of its unique morphological, physiological and phylogenetic properties, this strain represents the type species within a new genus, and we propose the name Methyloprofundus sedimenti gen. nov., sp. nov. The type strain of Methyloprofundus sedimenti is WF1(T) ( = LMG 28393(T) = ATCC BAA-2619(T)).


Assuntos
Sedimentos Geológicos/microbiologia , Methylococcaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , California , DNA Bacteriano/genética , Ácidos Graxos/química , Metano/metabolismo , Methylococcaceae/genética , Methylococcaceae/isolamento & purificação , Dados de Sequência Molecular , Oceano Pacífico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Environ Microbiol ; 16(6): 1592-611, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24148160

RESUMO

Microbes have obligate requirements for trace metals in metalloenzymes that catalyse important biogeochemical reactions. In anoxic methane- and sulphide-rich environments, microbes may have unique adaptations for metal acquisition and utilization because of decreased bioavailability as a result of metal sulphide precipitation. However, micronutrient cycling is largely unexplored in cold (≤ 10°C) and sulphidic (> 1 mM ΣH(2)S) deep-sea methane seep ecosystems. We investigated trace metal geochemistry and microbial metal utilization in methane seeps offshore Oregon and California, USA, and report dissolved concentrations of nickel (0.5-270 nM), cobalt (0.5-6 nM), molybdenum (10-5600 nM) and tungsten (0.3-8 nM) in Hydrate Ridge sediment porewaters. Despite low levels of cobalt and tungsten, metagenomic and metaproteomic data suggest that microbial consortia catalysing anaerobic oxidation of methane (AOM) utilize both scarce micronutrients in addition to nickel and molybdenum. Genetic machinery for cobalt-containing vitamin B12 biosynthesis was present in both anaerobic methanotrophic archaea (ANME) and sulphate-reducing bacteria. Proteins affiliated with the tungsten-containing form of formylmethanofuran dehydrogenase were expressed in ANME from two seep ecosystems, the first evidence for expression of a tungstoenzyme in psychrophilic microorganisms. Overall, our data suggest that AOM consortia use specialized biochemical strategies to overcome the challenges of metal availability in sulphidic environments.


Assuntos
Archaea/genética , Sedimentos Geológicos/microbiologia , Consórcios Microbianos/genética , Bactérias Redutoras de Enxofre/genética , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Transporte Biológico , California , Genes Arqueais , Genes Bacterianos , Sedimentos Geológicos/química , Metagenoma , Metano/metabolismo , Fenômenos Microbiológicos , Molibdênio/metabolismo , Níquel/metabolismo , Oregon , Oxirredução , Filogenia , Proteoma/genética , Proteoma/metabolismo , Tungstênio/metabolismo
13.
Mult Scler ; 20(2): 253-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24150778

RESUMO

Multiple sclerosis (MS) has a significant impact on health-related quality of life (HRQoL) with symptoms adversely affecting many aspects of everyday living. BG-12 (dimethyl fumarate) demonstrated significant efficacy in the phase III studies DEFINE and CONFIRM in patients with relapsing-remitting MS. In CONFIRM, HRQoL was worse in patients with greater disability at baseline, and who relapsed during the study, and improved with BG-12 treatment. Mean Short Form-36 Physical Component Summary scores for BG-12 increased over 2 years and scores for placebo decreased. Coupled with clinical and neuroradiological benefits, these HRQoL results further support BG-12 as an effective oral treatment for relapsing MS.


Assuntos
Fumaratos/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Qualidade de Vida , Adulto , Fumarato de Dimetilo , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Resultado do Tratamento
14.
Mult Scler ; 20(2): 243-52, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24150779

RESUMO

BACKGROUND: Oral BG-12 (dimethyl fumarate), approved for the treatment of the relapsing forms of MS, has demonstrated clinical efficacy with an acceptable safety profile in the Phase III "Determination of the Efficacy and Safety of Oral Fumarate in Relapsing-Remitting Multiple Sclerosis (RRMS)" (DEFINE) and "Comparator and an Oral Fumarate in RRMS" (CONFIRM) studies. OBJECTIVES: To evaluate the health-related quality of life (HRQoL) impairment that is associated with RRMS and to assess the effects of BG-12 on HRQoL in the DEFINE study. METHODS: Patients with RRMS were randomized to BG-12 240 mg twice (BID) or three times (TID) daily, or placebo, for 2 years. HRQoL was assessed by the Short Form-36 (SF-36), global assessment of well-being visual analog scale and the EuroQol-5D. RESULTS: In the 1237 patients from DEFINE, HRQoL impairment was greatest in patients who had higher disability scores and in those who had experienced relapse. Change in SF-36 physical component summary scores during 2 years' treatment significantly favored BG-12 over placebo (both doses: p < 0.001). We saw similar benefits in other measures of functioning and general well-being as early as Week 24. These benefits were maintained during the study. CONCLUSIONS: Our results add to evidence for a negative impact of RRMS on HRQoL and they demonstrate the benefits of BG-12 on HRQoL measures, which coupled with significant clinical efficacy, further support its use as a new treatment for RRMS.


Assuntos
Fumaratos/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Qualidade de Vida , Adulto , Fumarato de Dimetilo , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
15.
Ophthalmic Physiol Opt ; 33(3): 305-10, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23662962

RESUMO

PURPOSE/BACKGROUND: This study examined the effect of myopic defocus on visual acuity (VA) over time, with attention being paid to the first point at which blur adaptation had a significant and measurable effect on defocused VA. Visual acuity was sampled at a higher rate than previous studies in order to assess the time course of blur adaptation processes in myopic and emmetropic observers. METHODS: Participants were 24 normally-sighted observers (12 emmetropes and 12 myopes, median age: 22.5 years). All ametropic participants wore their full refractive correction throughout the experiment. 1 D and 3 D of myopic defocus were introduced in two separate, randomised sessions. Visual acuity was measured using Test Chart 2000 at 2 min intervals over a 30 min session whilst looking through defocus lenses. Recovery clear VA was also measured every 2 min for a further 20 min. RESULTS: Defocused VA was found to improve significantly within 4 min after the introduction of defocus for both 1 D (P < 0.0001) and 3 D conditions (P < 0.0001). The improvements reached a plateau shortly after, with no significant further improvements in defocused VA after 6 min. There were no significant differences found in the temporal blur adaptation profiles between emmetropes and myopes (P = 0.267). Data were fitted with an exponential decay function; the lowest R(2) value for this fit was 0.95. CONCLUSIONS: Blur adaptation has a clinically significant and measurable effect on VA within 4 min of exposure to defocus. This finding indicates that the visual system instigates the neural compensatory mechanisms shortly after the appearance of defocus. Our results relate particularly to real-life vision of uncorrected myopes or myopes who remove their correction for part of the day.


Assuntos
Adaptação Ocular/fisiologia , Emetropia/fisiologia , Miopia/fisiopatologia , Acuidade Visual/fisiologia , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
16.
Microorganisms ; 11(12)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38138031

RESUMO

Extreme environments, including hypersaline pools, often serve as biogeographical islands. Putative colonizers would need to survive transport across potentially vast distances of inhospitable terrain. Hyperhalophiles, in particular, are often highly sensitive to osmotic pressure. Here, we assessed whether hyperhalophiles are capable of rapidly colonizing an isolated and sterile hypersaline pool and the order of succession of the ensuing colonizers. A sterile and isolated 1 m3 hypersaline mesocosm pool was constructed on a rooftop in Charleston, SC. Within months, numerous halophilic lineages successfully navigated the 20 m elevation and the greater than 1 km distance from the ocean shore, and a vibrant halophilic community was established. All told, in a nine-month period, greater than a dozen halophilic genera colonized the pool. The first to arrive were members of the Haloarchaeal genus Haloarcula. Like a weed, the Haloarcula rapidly colonized and dominated the mesocosm community but were later supplanted by other hyperhalophilic genera. As a possible source of long-distance inoculum, both aerosol and water column samples were obtained from the Great Salt Lake and its immediate vicinity. Members of the same genus, Haloarcula, were preferentially enriched in the aerosol sample relative to the water column samples. Therefore, it appears that a diverse array of hyperhalophiles are capable of surviving aeolian long-distance transport and that some lineages, in particular, have possibly adapted to that strategy.

17.
EClinicalMedicine ; 59: 101971, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37152360

RESUMO

Background: No pharmacological treatments are specifically indicated for painful small fibre neuropathy (SFN). CONVEY, a phase 2 enriched-enrolment study, evaluated the efficacy and safety of vixotrigine, a voltage- and use-dependent sodium channel blocker, in participants with idiopathic or diabetes-associated painful SFN. Methods: CONVEY was a phase 2, multicentre, placebo-controlled, double-blind (DB), enriched-enrolment, randomised withdrawal study. The study was conducted at 68 sites in 13 countries (Europe and Canada) between May 17, 2018, and April 12, 2021. Following a 4-week open-label period in which 265 adults with painful SFN (a mixture of large and small fibre neuropathy was not exclusionary) received oral vixotrigine 350 mg twice daily (BID), 123 participants (with a ≥30% reduction from baseline in average daily pain [ADP] score during the open-label period) were randomised 1:1:1 to receive 200 mg BID, 350 mg BID or placebo for a 12-week double-blind (DB) period. Primary endpoint was change from baseline in ADP at DB Week 12. Secondary endpoints included the proportion of participants with a ≥30% reduction from baseline in ADP and the proportion of Patient Global Impression of Pain (PGIC) responders at DB Week 12. Treatment-emergent adverse events (AEs) were monitored. Statistical significance was set at 0.10 (2-sided). The trial was registered on ClinicalTrials.gov (NCT03339336) and on ClinicalTrialsregister.eu (2017-000991-27). Findings: A statistically significant difference from placebo in least squares mean reduction in ADP score from baseline to DB Week 12 was observed with vixotrigine 200 mg BID (-0.85; SE, 0.43; 95% CI, -1.71 to 0.00; p = 0.050) but not 350 mg BID (-0.17; SE, 0.43; 95% CI, -1.01 to 0.68; p = 0.70). Numerically, but not statistically significantly, more participants who received vixotrigine vs placebo experienced a ≥30% ADP reduction from baseline (68.3-72.5% vs 52.5%), and only the 350 mg BID group had significantly more PGIC responders vs placebo (48.8% vs 30.0%; odds ratio = 2.60; 95% CI, 0.97-6.99; p = 0.058) at DB Week 12. AEs were mostly mild to moderate in the vixotrigine groups. The most common AEs (≥5% of vixotrigine-treated participants) in the DB 200 mg BID and 350 mg BID vixotrigine groups were falls, nasopharyngitis, muscle spasm, and urinary tract infection. Interpretation: In our study, vixotrigine 200 mg BID, but not 350 mg BID, met the primary endpoint; more vixotrigine-treated participants experienced a ≥30% reduction from baseline in ADP at DB Week 12. Vixotrigine (at both dosages) was well tolerated in participants with SFN. Funding: Biogen, Inc.

18.
Appl Environ Microbiol ; 78(10): 3599-605, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22427501

RESUMO

Filter-collected production water samples from a methane-rich gas field in the Cook Inlet basin of Alaska were investigated using whole-cell rRNA-targeted fluorescence in situ hybridization (FISH) and 16S rRNA tag pyrosequencing. Both techniques were consistent in determining the microbial community composition, including the archaeal or bacterial dominance of samples. The archaeal community is dominated by the obligate methylotrophic methanogen genus Methanolobus as well as the nutritional generalist methanogen genus Methanosarcina, which is capable of utilizing acetate, CO(2), and methyl-bearing compounds. The most-abundant bacterial groups are Firmicutes, notably of the Acetobacterium genus, and Cytophaga-Flexibacter-Bacteroides species (CFBs) affiliated with the order Bacteroidales. We observed spatial variation among samples in both the percentage of members of Archaea compared to that of members of Bacteria and the dominant members of the bacterial community, differences which could not be explained with the available geochemical data. Based upon the microbial community composition and the isotopic signature of methane associated with the Cook Inlet basin site, we propose a simplified reaction network beginning with the breakdown of coal macromolecules, followed by fermentation and methylotrophic and acetoclastic methane production.


Assuntos
Archaea/classificação , Bactérias/classificação , Biota , Hibridização in Situ Fluorescente/métodos , Consórcios Microbianos , Campos de Petróleo e Gás/microbiologia , Microbiologia da Água , Acetatos/metabolismo , Alaska , Archaea/genética , Bactérias/genética , Dióxido de Carbono/metabolismo , Metano/metabolismo , Análise de Sequência de DNA
19.
Front Vet Sci ; 9: 956153, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36032307

RESUMO

Objective: This study aimed to describe a case of glomerulosclerosis resulting in nephrotic syndrome following the administration of pamidronate disodium to treat clinical calcitriol toxicity in a dog. Case summary: A 12-week-old intact male Labrador Retriever weighing 11.8 kg presented with lethargy and vomiting for 20 h after ingesting a 100 g tube of topical antipsoriatic cream (3 mcg/g of calcitriol; Vectical Ointment™, Galderma, Lausanne, Switzerland). Severe hypercalcemia was present on the day of the presentation. Hypercalcemia treatments such as saline diuresis, furosemide (Salix®, furosemide, Merck Animal Health, Kenilworth, NJ), and dexamethasone sodium phosphate (Dexamethasone SP, Mylan, Canonsburg, PA) were initiated. The dog was also administered a single dose of pamidronate disodium (Pamidronate disodium, Mylan, Canonsburg, PA) on the day of presentation. Initially, the patient's clinical signs improved, and the hypercalcemia resolved. Exactly 130 h post-pamidronate disodium (Dexamethasone SP, Mylan, Canonsburg, PA) administration, the patient developed biochemical abnormalities and severe edema, consistent with nephrotic syndrome, and was euthanized. Necropsy results revealed evidence of focal segmental glomerulosclerosis (FSGS). Unique information: Pamidronate disodium, commonly used for the treatment of hypercalcemia, may have resulted in glomerulosclerosis and nephrotic syndrome in a dog with calcitriol toxicity. This complication should be taken into consideration when monitoring patients treated with pamidronate disodium for hypercalcemia.

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