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151.
David Taylor Hendrixson Kristie Smith Patrick Lasowski Meghan Callaghan-Gillespie Jacklyn Weber Peggy Papathakis Per Ole Iversen Aminata Shamit Koroma Mark J. Manary 《PLoS medicine》2021,18(9)
BackgroundInnovations for undernourished pregnant women that improve newborn survival and anthropometry are needed to achieve the Sustainable Development Goals 1 and 3. This study tested the hypothesis that a combination of a nutritious supplementary food and several proven chemotherapeutic interventions to control common infections would increase newborn weight and length in undernourished pregnant women.Methods and findingsThis was a prospective, randomized, controlled clinical effectiveness trial of a ready-to-use supplementary food (RUSF) plus anti-infective therapies compared to standard therapy in undernourished pregnant women in rural Sierra Leone. Women with a mid-upper arm circumference (MUAC) ≤23.0 cm presenting for antenatal care at one of 43 government health clinics in Western Rural Area and Pujehun districts were eligible for participation. Standard of care included a blended corn/soy flour and intermittent preventive treatment for malaria in pregnancy (IPTp). The intervention replaced the blended flour with RUSF and added azithromycin and testing and treatment for vaginal dysbiosis. Since the study involved different foods and testing procedures for the intervention and control groups, no one except the authors conducting the data analyses were blinded. The primary outcome was birth length. Secondary outcomes included maternal weight gain, birth weight, and neonatal survival. Follow-up continued until 6 months postpartum. Modified intention to treat analyses was undertaken. Participants were enrolled and followed up from February 2017 until February 2020.Of the 1,489 women enrolled, 752 were allocated to the intervention and 737 to the standard of care. The median age of these women was 19.5 years, of which 42% were primigravid. Twenty-nine women receiving the intervention and 42 women receiving the standard of care were lost to follow-up before pregnancy outcomes were obtained. There were 687 singleton live births in the intervention group and 657 in the standard of care group. Newborns receiving the intervention were 0.3 cm longer (95% confidence interval (CI) 0.09 to 0.6; p = 0.007) and weighed 70 g more (95% CI 20 to 120; p = 0.005) than those receiving the standard of care. Those women receiving the intervention had greater weekly weight gain (mean difference 40 g; 95% CI 9.70 to 71.0, p = 0.010) than those receiving the standard of care. There were fewer neonatal deaths in the intervention (n = 13; 1.9%) than in the standard of care (n = 28; 4.3%) group (difference 2.4%; 95% CI 0.3 to 4.4), (HR 0.62 95% CI 0.41 to 0.94, p = 0.026). No differences in adverse events or symptoms between the groups was found, and no serious adverse events occurred. Key limitations of the study are lack of gestational age estimates and unblinded administration of the intervention.ConclusionsIn this study, we observed that the addition of RUSF, azithromycin, more frequent IPTp, and testing/treatment for vaginal dysbiosis in undernourished pregnant women resulted in modest improvements in anthropometric status of mother and child at birth, and a reduction in neonatal death. Implementation of this combined intervention in rural, equatorial Africa may well be an important, practical measure to reduce infant mortality in this context.Trial registrationClinicalTrials.gov .In a randomized trial, D. Taylor Hendrixson and colleagues investigate the effect of an intervention combining supplementary food and anti-infection medications on birth outcomes. NCT03079388相似文献
152.
Abstract Bacillus cereus T spores were extensively washed, broken, and heated at 90°C for 2 min. Using calcium-dependent hydrophobic interaction chromatography, a single peak protein fraction was obtained which possessed calcium-binding capacity and some characteristics of calmodulin. This heat-stable protein fraction was retained by hydrophobic matrices (Phenyl-Sepharose) or a calmodulin antagonist (naphthalenesulfonamide) in a calcium-dependent manner. Calcium binding ability was verified by 45 Ca autoradiography and a competitive calcium binding assay using Chelex-100. The crude spore extract displaced bovine brain calmodulin from its antibody in a radioimmunoassay and the immunoreactive specific activity of the partially purified fraction was approx. 200-fold greater than the crude spore extract. Thus, B. cereus T spores have a calcium-binding protein with calmodulin-like properties. 相似文献
153.
Chi Song Gary K. Chen Robert C. Millikan Christine B. Ambrosone Esther M. John Leslie Bernstein Wei Zheng Jennifer J. Hu Regina G. Ziegler Sarah Nyante Elisa V. Bandera Sue A. Ingles Michael F. Press Sandra L. Deming Jorge L. Rodriguez-Gil Stephen J. Chanock Peggy Wan Xin Sheng Loreall C. Pooler David J. Van Den Berg Loic Le Marchand Laurence N. Kolonel Brian E. Henderson Chris A. Haiman Daniel O. Stram 《PloS one》2013,8(2)
Genome-wide association studies (GWAS) simultaneously investigating hundreds of thousands of single nucleotide polymorphisms (SNP) have become a powerful tool in the investigation of new disease susceptibility loci. Haplotypes are sometimes thought to be superior to SNPs and are promising in genetic association analyses. The application of genome-wide haplotype analysis, however, is hindered by the complexity of haplotypes themselves and sophistication in computation. We systematically analyzed the haplotype effects for breast cancer risk among 5,761 African American women (3,016 cases and 2,745 controls) using a sliding window approach on the genome-wide scale. Three regions on chromosomes 1, 4 and 18 exhibited moderate haplotype effects. Furthermore, among 21 breast cancer susceptibility loci previously established in European populations, 10p15 and 14q24 are likely to harbor novel haplotype effects. We also proposed a heuristic of determining the significance level and the effective number of independent tests by the permutation analysis on chromosome 22 data. It suggests that the effective number was approximately half of the total (7,794 out of 15,645), thus the half number could serve as a quick reference to evaluating genome-wide significance if a similar sliding window approach of haplotype analysis is adopted in similar populations using similar genotype density. 相似文献
154.
Alessandra Apicella Peggy Heunemann Sreenath Bolisetty Matteo Marascio Anja Gemperli Graf Laszlo Garamszegi Raffaele Mezzenga Peter Fischer Christopher J. Plummer Jan-Anders M?nson 《PloS one》2015,10(12)
In a current procedure for periodontal tissue regeneration, enamel matrix derivative (EMD), which is the active component, is mixed with a propylene glycol alginate (PGA) gel carrier and applied directly to the periodontal defect. Exposure of EMD to physiological conditions then causes it to precipitate. However, environmental changes during manufacture and storage may result in modifications to the conformation of the EMD proteins, and eventually premature phase separation of the gel and a loss in therapeutic effectiveness. The present work relates to efforts to improve the stability of EMD-based formulations such as Emdogain™ through the incorporation of arginine, a well-known protein stabilizer, but one that to our knowledge has not so far been considered for this purpose. Representative EMD-buffer solutions with and without arginine were analyzed by 3D-dynamic light scattering, UV-Vis spectroscopy, transmission electron microscopy and Fourier transform infrared spectroscopy at different acidic pH and temperatures, T, in order to simulate the effect of pH variations and thermal stress during manufacture and storage. The results provided evidence that arginine may indeed stabilize EMD against irreversible aggregation with respect to variations in pH and T under these conditions. Moreover, stopped-flow transmittance measurements indicated arginine addition not to suppress precipitation of EMD from either the buffers or the PGA gel carrier when the pH was raised to 7, a fundamental requirement for dental applications. 相似文献
155.
Foraging habits in a generalist predator: Sex and age influence habitat selection and resource use among bottlenose dolphins (Tursiops truncatus) 下载免费PDF全文
Sam Rossman Elizabeth Berens McCabe Hasand Gandhi Peggy H. Ostrom Craig A. Stricker Randall S. Wells 《Marine Mammal Science》2015,31(1):155-168
This study examines resource use (diet, habitat use, and trophic level) within and among demographic groups (males, females, and juveniles) of bottlenose dolphins (Tursiops truncatus). We analyzed the δ13C and δ15N values of 15 prey species constituting 84% of the species found in stomach contents. We used these data to establish a trophic enrichment factor (TEF) to inform dietary analysis using a Bayesian isotope mixing model. We document a TEF of 0‰ and 2.0‰ for δ13C and δ15N, respectively. The dietary results showed that all demographic groups relied heavily on low trophic level seagrass‐associated prey. Bayesian standard ellipse areas (SEAb) were calculated to assess diversity in resource use. The SEAb of females was nearly four times larger than that of males indicating varied resource use, likely a consequence of small home ranges and habitat specialization. Juveniles possessed an intermediate SEAb, generally feeding at a lower trophic level compared to females, potentially an effect of natal philopatry and immature foraging skills. The small SEAb of males reflects a high degree of specialization on seagrass associated prey. Patterns in resource use by the demographic groups are likely linked to differences in the relative importance of social and ecological factors. 相似文献
156.
Synopsis The spawning and nesting behavior ofEtheostoma (Boleosoma) perlongum was investigated in the field and laboratory. Sexual dimorphism is highly developed in such features as genital papillae, first dorsal and paired fins, and nuptial coloration. A reproductive migration from mid-lake to shore occurs in the spring: males precede females to select nest sites under submerged sticks and other debris. The male excavates a depression beneath the submerged object. Gonad analysis indicates a single spawning season extending from March through June. Nests were found from late April to mid-June and were guarded by a single male for periods of 13 to 36 days. Males initiate courtship by lateral display, lead the female to the nest site and show the nest by inverting. The female responds by tail up, tail wag and circle; males also tail wag and circle. Spawning pairs invert, usually in unison, and orient head to head or, less often, head to tail. The female deposits eggs while holding her body in a weak S or J shape with the caudal peduncle held away from the spawning substrate while vibrating. 相似文献
157.
Simona Nardozza Helen L. Boldingh M. Peggy Kashuba Regina Feil Dan Jones Amali H. Thrimawithana Hilary S. Ireland Marine Philippe Mark W. Wohlers Tony K. McGhie Mirco Montefiori John E. Lunn Andrew C. Allan Annette C. Richardson 《Plant, cell & environment》2020,43(4):819-835
Kiwifruit (Actinidia spp.) is a recently domesticated fruit crop with several novel-coloured cultivars being developed. Achieving uniform fruit flesh pigmentation in red genotypes is challenging. To investigate the cause of colour variation between fruits, we focused on a red-fleshed Actinidia chinensis var. chinensis genotype. It was hypothesized that carbohydrate supply could be responsible for this variation. Early in fruit development, we imposed high or low (carbon starvation) carbohydrate supplies treatments; carbohydrate import or redistribution was controlled by applying a girdle at the shoot base. Carbon starvation affected fruit development as well as anthocyanin and carbohydrate metabolite concentrations, including the signalling molecule trehalose 6-phosphate. RNA-Seq analysis showed down-regulation of both gene-encoding enzymes in the anthocyanin and carbohydrate biosynthetic pathways. The catalytic trehalose 6-phosphate synthase gene TPS1.1a was down-regulated, whereas putative regulatory TPS7 and TPS11 were strongly up-regulated. Unexpectedly, under carbon starvation MYB10, the anthocyanin pathway regulatory activator was slightly up-regulated, whereas MYB27 was also up-regulated and acts as a repressor. To link these two metabolic pathways, we propose a model where trehalose 6-phosphate and the active repressor MYB27 are involved in sensing the carbon starvation status. This signals the plant to save resources and reduce the production of anthocyanin in fruits. 相似文献
158.
Margret Schmidt Aline Piro-Hussong Annett Siegemund Peggy Gabriel Wolfgang Dörr 《Radiation and environmental biophysics》2014,53(4):629-634
Early oral mucositis occurs in response to accidental upper partial body exposure as well as to radiotherapy in the head-and-neck region. This study was initiated to define the potential of mobilization of endogenous bone marrow (BM) stem cells by rHuG-CSF or of bone marrow transplantation (BMT) to reduce the effect of single-dose irradiation on mouse oral epithelium. A 3 × 3 mm2 area of the lower tongue surface of mice was irradiated with graded single doses (day 0). Mucosal ulceration was used as the endpoint for dose–response analyses. Stem cells were mobilized by rHuG-CSF (8 times/4 days), timed to achieve a maximum of circulating stem cells on days 0, +1, +4, +8 or +10. Alternatively, syngeneic BM was transplanted on these days. The ED50 (dose at which ulceration is expected in 50 % of the animals) for irradiation alone was 11.9 ± 3.4 Gy. Mobilization of stem cells with a maximum of circulating stem cells on days +4, +8 or +10 significantly increased the ED50 to 25.5 ± 10.1, 23.5 ± 10.1 and 26.5 ± 13.0 Gy. In contrast, a maximum of circulating stem cells on day 0 or day +1 had no effect. BMT did not result in a significant change in isoeffective doses in any of the protocols. In conclusion, the response of oral mucosal epithelium to a single-radiation exposure can be significantly reduced by post-exposure mobilization, but not by transplantation, of BM stem cells. 相似文献
159.
Kirst Henning Gabilly Stéphane T. Niyogi Krishna K. Lemaux Peggy G. Melis Anastasios 《Planta》2017,245(5):1009-1020
Planta - Evidence shows that decreasing the light-harvesting antenna size of the photosystems in tobacco helps to increase the photosynthetic productivity and plant canopy biomass accumulation... 相似文献
160.
Hammock Bruce G. Hartman Rosemary Dahlgren Randy A. Johnston Catherine Kurobe Tomofumi Lehman Peggy W. Lewis Levi S. Van Nieuwenhuyse Erwin Ramrez-Duarte Wilson F. Schultz Andrew A. Teh Swee J. 《Hydrobiologia》2022,849(3):675-695
Hydrobiologia - Condition indices are key predictors of health and fitness in wild fish populations. Variation in body condition, therefore, can be used to identify stressful conditions that may... 相似文献