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81.
Xiaoning Han Michael Chen Fushun Wang Martha Windrem Su Wang Steven Shanz Qiwu Xu Nancy Ann Oberheim Lane Bekar Sarah Betstadt Alcino J. Silva Takahiro Takano Steven A. Goldman Maiken Nedergaard 《Cell Stem Cell》2013,12(3):342-353
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82.
Alison M. Fung Danielle L. Wilson Martha Lappas Mark Howard Maree Barnes Fergal O'Donoghue Stephen Tong Helen Esdale Gabrielle Fleming Susan P. Walker 《PloS one》2013,8(7)
Objective
The objective of this study is to determine whether obstructive sleep apnea (OSA) is associated with reduced fetal growth, and whether nocturnal oxygen desaturation precipitates acute fetal heart rate changes.Study Design
We performed a prospective observational study, screening 371 women in the second trimester for OSA symptoms. 41 subsequently underwent overnight sleep studies to diagnose OSA. Third trimester fetal growth was assessed using ultrasound. Fetal heart rate monitoring accompanied the sleep study. Cord blood was taken at delivery, to measure key regulators of fetal growth.Results
Of 371 women screened, 108 (29%) were high risk for OSA. 26 high risk and 15 low risk women completed the longitudinal study; 14 had confirmed OSA (cases), and 27 were controls. The median (interquartile range) respiratory disturbance index (number of apnoeas, hypopnoeas or respiratory related arousals/hour of sleep) was 7.9 (6.1–13.8) for cases and 2.2 (1.3–3.5) for controls (p<0.001). Impaired fetal growth was observed in 43% (6/14) of cases, vs 11% (3/27) of controls (RR 2.67; 1.25–5.7; p = 0.04). Using logistic regression, only OSA (OR 6; 1.2–29.7, p = 0.03) and body mass index (OR 2.52; 1.09–5.80, p = 0.03) were significantly associated with impaired fetal growth. After adjusting for body mass index on multivariate analysis, the association between OSA and impaired fetal growth was not appreciably altered (OR 5.3; 0.93–30.34, p = 0.06), although just failed to achieve statistical significance. Prolonged fetal heart rate decelerations accompanied nocturnal oxygen desaturation in one fetus, subsequently found to be severely growth restricted. Fetal growth regulators showed changes in the expected direction- with IGF-1 lower, and IGFBP-1 and IGFBP-2 higher- in the cord blood of infants of cases vs controls, although were not significantly different.Conclusion
OSA may be associated with reduced fetal growth in late pregnancy. Further evaluation is warranted to establish whether OSA may be an important contributor to adverse perinatal outcome, including stillbirth. 相似文献83.
Philip Cooper Alan W. Walker Jorge Reyes Martha Chico Susannah J. Salter Maritza Vaca Julian Parkhill 《PloS one》2013,8(10)
Background
The soil-transmitted helminth (STH), Trichuris trichiura colonises the human large intestine where it may modify inflammatory responses, an effect possibly mediated through alterations in the intestinal microbiota. We hypothesised that patent T. trichiura infections would be associated with altered faecal microbiota and that anthelmintic treatment would induce a microbiota resembling more closely that observed in uninfected individuals.Materials and Methods
School children in Ecuador were screened for STH infections and allocated to 3 groups: uninfected, T. trichiura only, and mixed infections with T. trichiura and Ascaris lumbricoides. A sample of uninfected children and those with T. trichiura infections only were given anthelmintic treatment. Bacterial community profiles in faecal samples were studied by 454 pyrosequencing of 16 S rRNA genes.Results
Microbiota analyses of faeces were done for 97 children: 30 were uninfected, 17 were infected with T. trichiura, and 50 with T. trichiura and A. lumbricoides. Post-treatment samples were analyzed for 14 children initially infected with T. trichiura alone and for 21 uninfected children. Treatment resulted in 100% cure of STH infections. Comparisons of the microbiota at different taxonomic levels showed no statistically significant differences in composition between uninfected children and those with T. trichiura infections. We observed a decreased proportional abundance of a few bacterial genera from the Clostridia class of Firmicutes and a reduced bacterial diversity among children with mixed infections compared to the other two groups, indicating a possible specific effect of A. lumbricoides infection. Anthelmintic treatment of children with T. trichiura did not alter faecal microbiota composition.Discussion
Our data indicate that patent human infections with T. trichiura may have no effect on faecal microbiota but that A. lumbricoides colonisation might be associated with a disturbed microbiota. Our results also catalogue the microbiota of rural Ecuadorians and indicate differences with individuals from more urban industrialised societies. 相似文献84.
Martha Lissete Morales Villarreal Marina Padilha Antonio Diogo Silva Vieira Bernadette Dora Gombossy de Melo Franco Rafael Chacon Ruiz Martinez Susana Marta Isay Saad 《PloS one》2013,8(12)
Species-specific Quantitative Real Time PCR (qPCR) alone and combined with the use of propidium monoazide (PMA) were used along with the plate count method to evaluate the survival of the probiotic strains Lactobacillus acidophilus La-5 and Bifidobacterium animalis subsp. lactis Bb-12, and the bacteriocinogenic and potentially probiotic strain Lactobacillus sakei subsp. sakei 2a in synbiotic (F1) and probiotic (F2) petit-suisse cheeses exposed throughout shelf-life to in vitro simulated gastrointestinal tract conditions. The three strains studied showed a reduction in their viability after the 6 h assay. Bb-12 displayed the highest survival capacity, above 72.6 and 74.6% of the initial populations, respectively, by plate count and PMA-qPCR, maintaining population levels in the range or above 6 log CFU/g. The prebiotic mix of inulin and FOS did not offer any additional protection for the strains against the simulated gastrointestinal environment. The microorganisms'' populations were comparable among the three methods at the initial time of the assay, confirming the presence of mainly viable and culturable cells. However, with the intensification of the stress induced throughout the various stages of the in vitro test, the differences among the methods increased. The qPCR was not a reliable enumeration method for the quantification of intact bacterial populations, mixed with large numbers of injured and dead bacteria, as confirmed by the scanning electron microscopy results. Furthermore, bacteria plate counts were much lower (P<0.05) than with the PMA-qPCR method, suggesting the accumulation of stressed or dead microorganisms unable to form colonies. The use of PMA overcame the qPCR inability to differentiate between dead and alive cells. The combination of PMA and species-specific qPCR in this study allowed a quick and unequivocal way of enumeration of viable closely related species incorporated into probiotic and synbiotic petit-suisse cheeses and under stress conditions. 相似文献
85.
86.
Martín González‐Andrade Paulina Del Valle Martha ;L. Macías‐Rubalcava Alejandro Sosa‐Peinado María Del Carmen González Rachel Mata 《化学与生物多样性》2013,10(3):328-337
An organic extract was prepared from the culture medium and mycelia of the marine fungus Aspergillus stromatoides Raper & Fennell . The extract was fractionated via column chromatography, and the resulting fractions were tested for their abilities to quench the fluorescence of the calmodulin (CaM) biosensor hCaM M124C‐mBBr. From the active fraction, emodin ( 1 ) and ω‐hydroxyemodin ( 2 ) were isolated as CaM inhibitors. Anthraquinones 1 and 2 quenched the fluorescence of the hCaM M124C‐mBBr biosensor in a concentration‐dependent manner with Kd values of 0.33 and 0.76 μM , respectively. The results were compared with those of chlorpromazine (CPZ), a classical inhibitor of CaM, with a Kd value of 1.25 μM . Docking analysis revealed that 1 and 2 bind to the same pocket of CPZ. The CaM inhibitor properties of 1 and 2 were correlated with some of their reported biological properties. Citrinin ( 3 ), methyl 8‐hydroxy‐6‐methyl‐9‐oxo‐9H‐xanthene‐1‐carboxylate ( 4 ), and coniochaetone A ( 5 ) were also isolated in the present study. The X‐ray structure of 5 is reported for the first time. 相似文献
87.
Alvaro A. Sandoval-Montiel Martha Zentella-de-Pi?a José L. Ventura-Gallegos Susana Frías-González Ambar López-Macay Alejandro Zentella-Dehesa 《PloS one》2013,8(6)
Background
Among NSAIDs acetyl salicylic acid remains as a valuable tool because of the variety of benefic prophylactic and therapeutic effects. Nevertheless, the molecular bases for these responses have not been complete understood. We explored the effect of acetyl salicylic acid on the heat shock response.Results
Peripheral blood mononuclear cells from rats challenged with acetyl salicylic acid presented a faster kinetics of expression of HSP-72 messenger RNA and protein in response to in vitro heat shock. This effect reaches its maximum 2 h after treatment and disappeared after 5 h. On isolated peripheral blood mononuclear cells from untreated rats, incubation with acetyl salicylic acid was ineffective to produce priming, but this effect was mimicked when the cells were incubated with the combination of H2O2+ ASA.Conclusions
Administration of acetyl salicylic acid to rats alters HSP-72 expression mechanism in a way that it becomes more efficient in response to in vitro heat shock. The fact that in vitro acetyl salicylic acid alone did not induce this priming effect implies that in vivo other signals are required. Priming could be reproduces in vitro with the combination of acetyl salicylic acid+H2O2. 相似文献88.
Neal N. Padte Mar Boente-Carrera Chasity D. Andrews Jenny McManus Brooke F. Grasperge Agegnehu Gettie Jordana G. Coelho-dos-Reis Xiangming Li Douglass Wu Joseph T. Bruder Martha Sedegah Noelle Patterson Thomas L. Richie Chi-Huey Wong David D. Ho Sandhya Vasan Moriya Tsuji 《PloS one》2013,8(10)
A key strategy to a successful vaccine against malaria is to identify and develop new adjuvants that can enhance T-cell responses and improve protective immunity. Upon co-administration with a rodent malaria vaccine in mice, 7DW8-5, a recently identified novel analog of α-galactosylceramide (α-GalCer), enhances the level of malaria-specific protective immune responses more strongly than the parent compound. In this study, we sought to determine whether 7DW8-5 could provide a similar potent adjuvant effect on a candidate human malaria vaccine in the more relevant non-human primate (NHP) model, prior to committing to clinical development. The candidate human malaria vaccine, AdPfCA (NMRC-M3V-Ad-PfCA), consists of two non-replicating recombinant adenoviral (Ad) vectors, one expressing the circumsporozoite protein (CSP) and another expressing the apical membrane antigen-1 (AMA1) of Plasmodium falciparum. In several phase 1 clinical trials, AdPfCA was well tolerated and demonstrated immunogenicity for both humoral and cell-mediated responses. In the study described herein, 25 rhesus macaques received prime and boost intramuscular (IM) immunizations of AdPfCA alone or with an ascending dose of 7DW8-5. Our results indicate that 7DW8-5 is safe and well-tolerated and provides a significant enhancement (up to 9-fold) in malaria-specific CD8+ T-cell responses after both priming and boosting phases, supporting further clinical development. 相似文献
89.
Conservation is an important organizational focus for zoos and aquariums. Organizational identity theory predicts a relationship between what is central to organizations, such as their mission statements, and their strategic activities. Based on this theory, we tested how organizational missions relate to their conservation strategies and practices. Tax forms and websites provided data from 173 zoos and 38 aquariums in the Association of Zoos and Aquariums in North America. We analyzed conservation mission strength, organizational characteristics, and project features with dependent variables representing the depth of organizational conservation commitments: amount of grants zoos funded, number of partner organizations, and number of projects per zoo. On tax forms, the average amount of total conservation grants donated to partner organizations per zoo was over $650,000, while the average number of partners reported on the tax forms was two. The content analysis of websites revealed an average of 14 conservation partners and 10 projects per zoo. Negative binomial regression models were significant. The financial analysis revealed that only the number of zoo personnel, as a surrogate for organization size, significantly predicted the amount of zoos’ conservation grants. Website analyses found increasing budgets, organizational involvement, and geographic reach of the projects predicted increasing numbers of conservation projects and partnerships. However, our findings did not support the hypothesized relationship—strength of organizational mission did not predict strategy and activities. Zoos could do more to strategically activate their organizational identities and conservation missions to achieve their conservation goals. 相似文献
90.
Vincent R. Farallo Martha M. Muñoz Josef C. Uyeda Donald B. Miles 《Evolution; international journal of organic evolution》2020,74(5):979-991
Macroclimatic niches are indirect and potentially inadequate predictors of the realized environmental conditions that many species experience. Consequently, analyses of niche evolution based on macroclimatic data alone may incompletely represent the evolutionary dynamics of species niches. Yet, understanding how an organisms’ climatic (Grinnellian) niche responds to changing macroclimatic conditions is of vital importance for predicting their potential response to global change. In this study, we integrate microclimatic and macroclimatic data across 26 species of plethodontid salamanders to portray the relationship between microclimatic niche evolution in response to changing macroclimate. We demonstrate stronger phylogenetic signal in microclimatic niche variables than at the macroclimatic scale. Even so, we find that the microclimatic niche tracks climatic changes at the macroscale, but with a phylogenetic lag at million-year timescales. We hypothesize that behavioral tracking of the microclimatic niche over space and phenology generates the lag: salamanders preferentially select microclimates similar to their ancestral conditions rather than adapting with changes in physiology. We demonstrate that macroclimatic variables are weak predictors of niche evolution and that incorporating spatial scale into analyses of niche evolution is critical for predicting responses to climate change. 相似文献