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91.
Alicia Ely Yamin Vanessa M. Boulanger Kathryn L. Falb Jane Shuma Jennifer Leaning 《PloS one》2013,8(8)
Background
Little is known about the interconnectedness of maternal deaths and impacts on children, beyond infants, or the mechanisms through which this interconnectedness is established. A study was conducted in rural Tanzania to provide qualitative insight regarding how maternal mortality affects index as well as other living children and to identify shared structural and social factors that foster high levels of maternal mortality and child vulnerabilities.Methods and Findings
Adult family members of women who died due to maternal causes (N = 45) and key stakeholders (N = 35) participated in in-depth interviews. Twelve focus group discussions were also conducted (N = 83) among community leaders in three rural regions of Tanzania. Findings highlight the widespread impact of a woman’s death on her children’s health, education, and economic status, and, by inference, the roles that women play within their families in rural Tanzanian communities.Conclusions
The full costs of failing to address preventable maternal mortality include intergenerational impacts on the nutritional status, health, and education of children, as well as the economic capacity of families. When setting priorities in a resource-poor, high maternal mortality country, such as Tanzania, the far-reaching effects that reducing maternal deaths can have on families and communities, as well as women’s own lives, should be considered. 相似文献92.
Amphetamine has well‐established actions on pre‐synaptic dopamine signaling, such as inhibiting uptake and degradation, activating synthesis, depleting vesicular stores, and promoting dopamine‐transporter reversal and non‐exocytotic release. Recent in vivo studies have identified an additional mechanism: augmenting vesicular release. In this study, we investigated how amphetamine elicits this effect. Our hypothesis was that amphetamine enhances vesicular dopamine release in dorsal and ventral striata by differentially targeting dopamine synthesis and degradation. In urethane‐anesthetized rats, we employed voltammetry to monitor dopamine, electrical stimulation to deplete stores or assess vesicular release and uptake, and pharmacology to isolate degradation and synthesis. While amphetamine increased electrically evoked dopamine levels, inhibited uptake, and up‐regulated vesicular release in both striatal sub‐regions in controls, this psychostimulant elicited region‐specific effects on evoked levels and vesicular release but not uptake in drug treatments. Evoked levels better correlated with vesicular release compared with uptake, supporting enhanced vesicular release as an important amphetamine mechanism. Taken together, these results suggested that amphetamine enhances vesicular release in the dorsal striatum by activating dopamine synthesis and inhibiting dopamine degradation, but targeting an alternative mechanism in the ventral striatum. Region‐distinct activation of vesicular dopamine release highlights complex cellular actions of amphetamine and may have implications for its behavioral effects. 相似文献
93.
Inmaculada Bautista-Casta?o Patricia Henriquez-Sanchez Nestor Alemán-Perez Jose J. Garcia-Salvador Alicia Gonzalez-Quesada Jose A. García-Hernández Luis Serra-Majem 《PloS one》2013,8(11)
Objectives
To assess the role of the health consequences of maternal overweight and obesity at the start of pregnancy on gestational pathologies, delivery and newborn characteristics.Methods
A cohort of pregnant women (n = 6.558) having delivered at the Maternal & Child University Hospital of Gran Canaria (HUMIGC) in 2008 has been studied. Outcomes were compared using multivariate analyses controlling for confounding variables.Results
Compared to normoweight, overweight and obese women have greater risks of gestational diabetes mellitus (RR = 2.13 (95% CI: 1.52–2.98) and (RR = 2.85 (95% CI: 2.01–4.04), gestational hypertension (RR = 2.01 (95% CI: 1.27–3.19) and (RR = 4.79 (95% CI: 3.13–7.32) and preeclampsia (RR = 3.16 (95% CI: 1.12–8.91) and (RR = 8.80 (95% CI: 3.46–22.40). Obese women have also more frequently oligodramnios (RR = 2.02 (95% CI: 1.25–3.27), polyhydramnios. (RR = 1.76 (95% CI: 1.03–2.99), tearing (RR = 1.24 (95% CI: 1.05–1.46) and a lower risk of induced deliveries (RR = 0.83 (95% CI: 0.72–0.95). Both groups have more frequently caesarean section (RR = 1.36 (95% CI: 1.14–1.63) and (RR = 1.84 (95% CI: 1.53–2.22) and manual placenta extraction (RR = 1.65 (95% CI: 1.28–2.11) and (RR = 1.77 (95% CI: 1.35–2.33). Newborns from overweight and obese women have higher weight (p<0.001) and a greater risk of being macrosomic (RR = 2.00 (95% CI: 1.56–2.56) and (RR = 2.74 (95% CI: 2.12–3.54). Finally, neonates from obese mother have a higher risk of being admitted to special care units (RR = 1.34 (95% CI: 1.01–1.77). Apgar 1 min was significantly higher in newborns from normoweight mothers: 8.65 (95% CI: 8.62–8.69) than from overweight: 8.56 (95% CI: 8.50–8.61) or obese mothers: 8.48 (95% CI: 8.41–8.54).Conclusion
Obesity and overweight status at the beginning of pregnancy increase the adverse outcomes of the pregnancy. It is important to promote the normalization of bodyweight in those women who intend to get pregnant and to provide appropriate advice to the obese women of the risks of obesity at the start of the pregnancy. 相似文献94.
Sánchez-Rodríguez MA Santiago E Arronte-Rosales A Vargas-Guadarrama LA Mendoza-Núñez VM 《Life sciences》2006,78(15):1682-1687
Psychological stress and environmental pollution are frequently associated to urban environment and oxidative stress (OxS). Likewise, OxS is a risk factor for cognitive impairment (CI) in the elderly. Therefore, we hypothesized that the prevalence of CI in subjects of the urban area could be higher than in those of the rural area, and linked to higher OxS. The aim of the study was to determine the relationship between OxS and CI in elderly individuals from rural and urban settings in Mexico. Plasmatic TBARS, plasma total antioxidant status, and the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured in 104 urban and 85 rural elderly individuals. Cognitive functions were evaluated through the Mini Mental State Examination. We found a greater proportion of subjects with OxS and CI in urban than in rural areas (25% vs. 9%), with an odds ratio of 5.67 (CI95% 1.14-38.02, p < 0.05). Our findings suggest that the elderly in urban areas have more OxS and a higher risk of developing CI compared with elderly individuals in a rural environment. 相似文献
95.
Joshua M. Plotnik Jennifer J. Pokorny Titiporn Keratimanochaya Christine Webb Hana F. Beronja Alice Hennessy James Hill Virginia J. Hill Rebecca Kiss Caitlin Maguire Beckett L. Melville Violet M. B. Morrison Dannah Seecoomar Benjamin Singer Jehona Ukehaxhaj Sophia K. Vlahakis Dora Ylli Nicola S. Clayton John Roberts Emilie L. Fure Alicia P. Duchatelier David Getz 《PloS one》2013,8(4)
Recent research suggests that domesticated species – due to artificial selection by humans for specific, preferred behavioral traits – are better than wild animals at responding to visual cues given by humans about the location of hidden food. \Although this seems to be supported by studies on a range of domesticated (including dogs, goats and horses) and wild (including wolves and chimpanzees) animals, there is also evidence that exposure to humans positively influences the ability of both wild and domesticated animals to follow these same cues. Here, we test the performance of Asian elephants (Elephas maximus) on an object choice task that provides them with visual-only cues given by humans about the location of hidden food. Captive elephants are interesting candidates for investigating how both domestication and human exposure may impact cue-following as they represent a non-domesticated species with almost constant human interaction. As a group, the elephants (n = 7) in our study were unable to follow pointing, body orientation or a combination of both as honest signals of food location. They were, however, able to follow vocal commands with which they were already familiar in a novel context, suggesting the elephants are able to follow cues if they are sufficiently salient. Although the elephants’ inability to follow the visual cues provides partial support for the domestication hypothesis, an alternative explanation is that elephants may rely more heavily on other sensory modalities, specifically olfaction and audition. Further research will be needed to rule out this alternative explanation. 相似文献
96.
Zhong-Wei Zhou Alicia Tapias Christopher Bruhn Ralph Gruber Mikhail Sukchev Zhao-Qi Wang 《DNA Repair》2013,12(8):645-655
MCPH1 encodes BRCT-containing protein MCPH1/Microcephalin/BRIT1, mutations of which in humans cause autosomal recessive disorder primary microcephaly type 1 (MCPH1), characterized by a congenital reduction of brain size particularly in the cerebral cortex. We have shown previously that a deletion of Mcph1 in mice results in microcephaly because of a premature switch from symmetric to asymmetric division of the neuroprogenitors, which is regulated by MCPH1's function in the centrosome. Because MCPH1 has been implicated in ATM and ATR-mediated DNA damage response (DDR) and defective DDR is often associated with neurodevelopmental diseases, we wonder whether the DDR-related function of MCPH1 prevents microcephaly. Here, we show that a deletion of Mcph1 results in a specific reduction of the cerebral cortex at birth, which is persistent through life. Due to an effect on premature neurogenic production, Mcph1-deficient progenitors give rise to a high level of early-born neurons that form deep layers (IV–VI), while generate less late-born neurons that form a thinner outer layer (II–III) of the cortex. However, neuronal migration seems to be unaffected by Mcph1 deletion. Ionizing radiation (IR) induces a massive apoptosis in the Mcph1-null neocortex and also embryonic lethality. Finally, Mcph1 deletion compromises homologous recombination repair and increases genomic instability. Altogether, our data suggest that MCPH1 ensures proper neuroprogenitor expansion and differentiation not only through its function in the centrosome, but also in the DDR. 相似文献
97.
Pedro Josué Trejo-Soto Alicia Hernández-Campos Antonio Romo-Mancillas José L. Medina-Franco 《Journal of biomolecular structure & dynamics》2018,36(2):423-442
The AKT isoforms are a group of key kinases that play a critical role in tumorigenesis. These enzymes are overexpressed in different types of cancers, such as breast, colon, prostate, ovarian, and lung. Because of its relevance the AKT isoforms are attractive targets for the design of anticancer molecules. However, it has been found that AKT1 and AKT3 isoforms have a main role in tumor progression and metastasis; thus, the identification of AKT isoforms specific inhibitors seems to be a challenge. Previously, we identified an ATP binding pocket pan-AKT inhibitor, this compound is a 2,4,6-trisubstituted pyridine (compound 11), which represents a new interesting scaffold for the developing of AKT inhibitors. Starting from the 2,4,6-trisubstituted pyridine scaffold, and guided by structure-based design technique, 42 new inhibitors were designed and further evaluated in the three AKT isoforms by multiple docking approach and molecular dynamics. Results showed that seven compounds presented binding selectivity for AKT1 and AKT3, better than for AKT2. The binding affinities of these seven compounds on AKT1 and AKT3 isoforms were mainly determined by hydrophobic contributions between the aromatic portion at position 4 of the pyridine ring with residues Phe236/234, Phe237/235, Phe438/435, and Phe442/439 in the ATP binding pocket. Results presented in this work provide an addition knowledge leading to promising selective AKT inhibitors. 相似文献
98.
99.
Alicia Mathis W. Wyatt Hoback 《Ethology : formerly Zeitschrift fur Tierpsychologie》1997,103(1):33-40
Many amphipod crustaceans exhibit precopulatory mate guarding. Field samples of the amphipod Gammarus pseudolimnaeus indicated that pairs were positively size assortative. Receptive individuals readily formed pairs in the laboratory and the latency to formation of precopulatory pairs was decreased under threat of predation. In addition, females and, under conditions of extreme danger, males that formed pairs were significantly smaller when under the threat of predation. Amphipods distinguished between chemical stimuli (aquarium water) from predatory and nonpredatory fishes and between chemical cues from fish predators (trout) that had recently eaten conspecific amphipods vs. those fed a control diet of pelleted commercial fish food. These data indicate that chemical stimuli associated with predators can influence reproductive behavior of amphipods. The results also suggest the hypotheses that: 1. search time may be costly in terms of probability of predation; and 2. small pairs may be safer from predation than larger pairs. 相似文献
100.
Two new species of the cryptogonimid genus Parspina Pearse, 1920 are described from gymnotiform fishes of the Paraná River basin, P. carapo n. sp. from the banded knifefish Gymnotus carapo Linnaeus and P. virescens n. sp. from the glass knifefish Eigenmannia virescens (Valenciennes). Parspina
carapo differs from P. virescens in the number of oral spines (32–39 vs 30–33) and their length (28–47 vs 16–28 μm), the distribution of tegumental spines and their anchorage, the types of sensory papillae on the body surface (three
vs two types), the extent of body length posterior to the caeca (5 vs 13% of the total body length), the dimensions of the pars prostatica (52 × 34 vs 24 × 10 μm), and in the absence of a gonotyl (vs presence). Both P. carapo and P. virescens differ from P. bagre Pearse, 1920 and P. argentinensis (Szidat, 1954) in the number of oral spines (20–21 and 21–28 in the latter pair) and their length (28–32 and 35–60 μm), and in total body
length. Additionally, the two new species differ from P. argentinensis in the arrangement of the vitelline follicles (one continuous band vs two groups on each side of the body) and in having a smaller pars prostatica (149 × 49 μm in the latter). Parspina carapo is the fifth intestinal helminth found in G. carapo, and P. virescens is the first found in E. virescens. 相似文献