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121.
B Abt C Han C Scheuner M Lu A Lapidus M Nolan S Lucas N Hammon S Deshpande JF Cheng R Tapia LA Goodwin S Pitluck K Liolios I Pagani N Ivanova K Mavromatis N Mikhailova M Huntemann A Pati A Chen K Palaniappan M Land L Hauser EM Brambilla M Rohde S Spring S Gronow M Göker T Woyke J Bristow JA Eisen V Markowitz P Hugenholtz NC Kyrpides HP Klenk JC Detter 《Standards in genomic sciences》2012,6(2):194-209
Spirochaeta coccoides Dröge et al. 2006 is a member of the genus Spirochaeta Ehrenberg 1835, one of the oldest named genera within the Bacteria. S. coccoides is an obligately anaerobic, Gram-negative, non-motile, spherical bacterium that was isolated from the hindgut contents of the termite Neotermes castaneus. The species is of interest because it may play an important role in the digestion of breakdown products from cellulose and hemicellulose in the termite gut. Here we provide a taxonomic re-evaluation for strain SPN1T, and based on physiological and genomic characteristics, we propose its reclassification as a novel species in the genus Sphaerochaeta, a recently published sister group of the Spirochaeta. The 2,227,296 bp long genome of strain SPN1T with its 1,866 protein-coding and 58 RNA genes is a part of the Genomic
Encyclopedia of
Bacteria and
Archaea project. 相似文献
122.
TA Odeny RC Bailey EA Bukusi JM Simoni KA Tapia K Yuhas KK Holmes RS McClelland 《PloS one》2012,7(9):e43832
Background
Following male circumcision for HIV prevention, a high proportion of men fail to return for their scheduled seven-day post-operative visit. We evaluated the effect of short message service (SMS) text messages on attendance at this important visit.Methodology
We enrolled 1200 participants >18 years old in a two-arm, parallel, randomized controlled trial at 12 sites in Nyanza province, Kenya. Participants received daily SMS text messages for seven days (n = 600) or usual care (n = 600). The primary outcome was attendance at the scheduled seven-day post-operative visit. The primary analysis was by intention-to-treat.Principal Findings
Of participants receiving SMS, 387/592 (65.4%) returned, compared to 356/596 (59.7%) in the control group (relative risk [RR] = 1.09, 95% confidence interval [CI] 1.00–1.20; p = 0.04). Men who paid more than US$1.25 to travel to clinic were at higher risk for failure to return compared to those who spent ≤US$1.25 (adjusted relative risk [aRR] 1.35, 95% CI 1.15–1.58; p<0.001). Men with secondary or higher education had a lower risk of failure to return compared to those with primary or less education (aRR 0.87, 95% CI 0.74–1.01; p = 0.07).Conclusions
Text messaging resulted in a modest improvement in attendance at the 7-day post-operative clinic visit following adult male circumcision. Factors associated with failure to return were mainly structural, and included transportation costs and low educational level.Trial Registration
ClinicalTrials.gov NCT01186575 相似文献123.
Lagos CF Araya-Secchi R Thomas P Pérez-Acle T Tapia RA Salas CO 《Journal of molecular modeling》2012,18(5):2055-2064
Trypanosoma cruzi glutamate cysteine ligase (TcGCL) is considered a potential drug target to develop novel antichagasic drugs. We have used
a variety of computational methods to investigate the interactions between TcGCL with Glutathione (GSH). The three-dimensional
structure of TcGCL was constructed by comparative modeling methods using the Saccharomyces cerevisiae glutamate cysteine ligase as template. Molecular dynamics simulations were used to validate the TcGCL model and to analyze
the molecular interactions with GSH. Using RMSD clustering, the most prevalent GSH binding modes were identified paying attention
to the residues involved in the molecular interactions. The GSH binding modes were used to propose pharmacophore models that
can be exploited in further studies to identify novel antichagasic compounds. 相似文献
124.
Sandra López Beatriz Lima Liliana Aragón Luis Ariza Espinar Alejandro Tapia Susana Zacchino Julio Zygadlo Gabriela Egly Feresin María Liza López 《化学与生物多样性》2012,9(8):1452-1464
The essential oils (EOs) of two populations of Azorella cryptantha (Clos) Reiche , a native species from San Juan Province, were obtained by hydrodistillation in a Clevenger‐type apparatus and characterized by GC‐FID and GC/MS analyses. The compounds identified amounted to 92.3 and 88.7% of the total oil composition for A. cryptantha from Bauchaceta (Ac‐BAU) and Agua Negra (Ac‐AN), respectively. The EO composition for the two populations was similar, although with differences in the identity and content of the main compounds and also in the identity of minor components. The main compounds of the Ac‐BAU EO were α‐pinene, α‐thujene, sabinene, δ‐cadinene, δ‐cadinol, trans‐β‐guaiene, and τ‐muurolol, while α‐pinene, α‐thujene, β‐pinene, γ‐cadinene, τ‐cadinol, δ‐cadinene, τ‐muurolol, and a not identified compound were the main constituents of the Ac‐AN EO, which also contained 3.0% of oxygenated monoterpenes. The repellent activity on Triatoma infestans nymphs was 100 and 92% for the Ac‐AN and Ac‐BAU EOs, respectively. Regarding the toxic effects on Ceratitis capitata, the EOs were very active with LD50 values lower than 11 μg/fly. The dermatophytes Microsporum gypseum, Trichophyton rubrum, and T. mentagrophytes and the bacterial strains Escherichia coli LM1, E. coli LM2, and Yersinia enterocolitica PI were more sensitive toward the Ac‐AN EO (MIC 125 μg/ml) than toward the Ac‐BAU EO. This is the first report on the composition of A. cryptantha EO and its anti‐insect and antimicrobial properties. 相似文献
125.
126.
Lauren A. V. Orenstein Evan W. Orenstein Ibrahima Teguete Mamoudou Kodio Milagritos Tapia Samba O. Sow Myron M. Levine 《PloS one》2012,7(10)
Background
Maternal immunization has gained traction as a strategy to diminish maternal and young infant mortality attributable to infectious diseases. Background rates of adverse pregnancy outcomes are crucial to interpret results of clinical trials in Sub-Saharan Africa.Methods
We developed a mathematical model that calculates a clinical trial''s expected number of neonatal and maternal deaths at an interim safety assessment based on the person-time observed during different risk windows. This model was compared to crude multiplication of the maternal mortality ratio and neonatal mortality rate by the number of live births. Systematic reviews of severe acute maternal morbidity (SAMM), low birth weight (LBW), prematurity, and major congenital malformations (MCM) in Sub-Saharan African countries were also performed.Findings
Accounting for the person-time observed during different risk periods yields lower, more conservative estimates of expected maternal and neonatal deaths, particularly at an interim safety evaluation soon after a large number of deliveries. Median incidence of SAMM in 16 reports was 40.7 (IQR: 10.6–73.3) per 1,000 total births, and the most common causes were hemorrhage (34%), dystocia (22%), and severe hypertensive disorders of pregnancy (22%). Proportions of liveborn infants who were LBW (median 13.3%, IQR: 9.9–16.4) or premature (median 15.4%, IQR: 10.6–19.1) were similar across geographic region, study design, and institutional setting. The median incidence of MCM per 1,000 live births was 14.4 (IQR: 5.5–17.6), with the musculoskeletal system comprising 30%.Interpretation
Some clinical trials assessing whether maternal immunization can improve pregnancy and young infant outcomes in the developing world have made ethics-based decisions not to use a pure placebo control. Consequently, reliable background rates of adverse pregnancy outcomes are necessary to distinguish between vaccine benefits and safety concerns. Local studies that quantify population-based background rates of adverse pregnancy outcomes will improve safety assessment of interventions during pregnancy. 相似文献127.
Rodrigo Valenzuela Alejandra Espinosa Daniel González-Ma?án Amanda D'Espessailles Virginia Fernández Luis A. Videla Gladys Tapia 《PloS one》2012,7(10)
Omega-3 (n-3) long-chain polyunsaturated fatty acids (n-3 LCPUFA) are associated with several physiological functions, suggesting that their administration may prevent non transmissible chronic diseases. Therefore, we investigate whether dietary n-3 LCPUFA supplementation triggers an antioxidant response preventing liver steatosis in mice fed a high fat diet (HFD) in relation to n-3 LCPUFA levels. Male C57BL/6J mice received (a) control diet (10% fat, 20% protein, 70% carbohydrate), (b) control diet plus n-3 LCPUFA (108 mg/kg/day eicosapentaenoic acid plus 92 mg/kg/day docosahexaenoic acid), (c) HFD (60% fat, 20% protein, 20% carbohydrate), or (d) HFD plus n-3 LCPUFA for 12 weeks. Parameters of liver steatosis, glutathione status, protein carbonylation, and fatty acid analysis were determined, concomitantly with insulin resistance and serum tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 levels. HFD significantly increased total fat and triacylglyceride contents with macrovesicular steatosis, concomitantly with higher fasting serum glucose and insulin levels, HOMA, and serum TNF-α, IL-1β, and IL-6. Reduced and total liver glutathione contents were diminished by HFD, with higher GSSG/GSH ratio and protein carbonylation, n-3 LCPUFA depletion and elevated n-6/n-3 ratio over control values. These changes were either reduced or normalized to control values in animals subjected to HFD and n-3 LCPUFA, with significant increased hepatic total n-3 LCPUFA content and reduced n-6/n-3 ratio being observed after n-3 LCPUFA supplementation alone. So, repletion of liver n-3 LCPUFA levels by n-3 LCPUFA dietary supplementation in HFD obese mice reduces hepatic lipid content, with concomitant antioxidant and anti-inflammatory responses favouring insulin sensitivity. 相似文献
128.
129.
Jingtao Huang Ian M Colrain Howard B Panitch Ignacio E Tapia Michael S Schwartz John Samuel Michelle Pepe Preetam Bandla Ruth Bradford Yael P Mosse John M Maris Carole L Marcus 《Journal of applied physiology》2008,105(1):44-53
The early literature suggests that hypoventilation in infants with congenital central hypoventilation syndrome (CHS) is less severe during rapid eye movement (REM) than during non-REM (NREM) sleep. However, this supposition has not been rigorously tested, and subjects older than infancy have not been studied. Given the differences in anatomy, physiology, and REM sleep distribution between infants and older children, and the reduced number of limb movements during REM sleep, we hypothesized that older subjects with CHS would have more severe hypoventilation during REM than NREM sleep. Nine subjects with CHS, aged (mean +/- SD) 13 +/- 7 yr, were studied. Spontaneous ventilation was evaluated by briefly disconnecting the ventilator under controlled circumstances. Arousal was common, occurring in 46% of REM vs. 38% of NREM trials [not significant (NS)]. Central apnea occurred during 31% of REM and 54% of NREM trials (NS). Although minute ventilation declined precipitously during both REM and NREM trials, hypoventilation was less severe during REM (drop in minute ventilation of 65 +/- 23%) than NREM (drop of 87 +/- 16%, P = 0.036). Despite large changes in gas exchange during trials, there was no significant change in heart rate during either REM or NREM sleep. We conclude that older patients with CHS frequently have arousal and central apnea, in addition to hypoventilation, when breathing spontaneously during sleep. The hypoventilation in CHS is more severe during NREM than REM sleep. We speculate that this may be due to increased excitatory inputs to the respiratory system during REM sleep. 相似文献
130.
Microdialysis perfusion of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) in rat lumbar spinal cord produces severe motoneuron damage and consequently hindlimb paralysis. Here we studied the time course of the AMPA-induced neurodegenerative changes and motor alterations, and the protective effect of leupeptin, an inhibitor of calpain, a Ca(2+)-activated protease. Paralysis occurs at 4-6 h after AMPA perfusion, but cresyl violet staining showed that motoneuron damage starts at about 3 h and progresses until reaching 50% neuronal loss at 6 h and 90% loss at 12 h. In contrast, choline acetyltransferase (ChAT) immunohistochemistry revealed that the enzyme is already decreased at 30 min after AMPA perfusion and practically disappears at 3 h. Microdialysis coperfusion of leupeptin with AMPA prevented the motor alterations and paralysis and remarkably reduced both the decrement in ChAT immunoreactivity and the loss of motoneurons. We conclude that an increased Ca(2+) influx through Ca(2+)-permeable AMPA receptors activates calpain, and as a consequence ChAT content decreases earlier than other Ca(2+)-dependent processes, including the proteolytic activity of calpain, cause the death of motoneurons. 相似文献