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121.
Background
HIV-related outcomes may be affected by biological sex and by pregnancy. Including women in general and pregnant women in particular in HIV-related research is important for generalizability of findings.Objective
To characterize representation of pregnant and non-pregnant women in HIV-related research conducted in general populations.Data Sources
All HIV-related articles published in fifteen journals from January to March of 2011. We selected the top five journals by 2010 impact factor, in internal medicine, infectious diseases, and HIV/AIDS.Study Eligibility Criteria
HIV-related studies reporting original research on questions applicable to both men and women of reproductive age were considered; studies were excluded if they did not include individual-level patient data.Study appraisal and synthesis methods.
Articles were doubly reviewed and abstracted; discrepancies were resolved through consensus. We recorded proportion of female study participants, whether pregnant women were included or excluded, and other key factors.Results
In total, 2014 articles were published during this period. After screening, 259 articles were included as original HIV-related research reporting individual-level data; of these, 226 were determined to be articles relevant to both men and women of reproductive age. In these articles, women were adequately represented within geographic region. The vast majority of published articles, 183/226 (81%), did not mention pregnancy (or related issues); still fewer included pregnant women (n=33), reported numbers of pregnant women (n=19), or analyzed using pregnancy status (n=9).Limitations
Data were missing for some key variables, including pregnancy. The time period over which published works were evaluated was relatively short.Conclusions and implications of key findings.
The under-reporting and inattention to pregnancy in the HIV literature may reduce policy-makers’ ability to set evidence-based policy around HIV/AIDS care for pregnant women and women of child-bearing age. 相似文献122.
Satoshi Tamura Masaki Ueno Masayuki Maeda Hisako Kawakami Kyouichi Sekine 《Free radical research》2013,47(11):1198-1205
The involvement of reactive oxygen species (ROS) and oxidative stress in pediatric diseases is an important concern, but oxidative stress status in healthy young subjects and appropriate methods for its measurement remain unclear. This study evaluated a comprehensive set of urinary biomarkers for oxidative stress in healthy children, adolescents and young adults. Results show that urinary excretion of acrolein–lysine, 8-hydroxy-2′-deoxyguanosine (8-OHdG), nitrite/nitrate and pentosidine were highest in the youngest subjects and decreased to constant levels by early adolescence. Urinary acrolein–lysine, 8-OHdG, nitrite/nitrate and pentosidine showed significant inverse correlations with age, but pyrraline did not change significantly with age. No significant differences in biomarkers were apparent between males and females. Younger subjects grow rapidly and sustain immune activation, and are probably exposed to high concentrations of ROS and nitric oxide. Consequently, they are more vulnerable to oxidation of lipids, proteins, DNA and carbohydrates. Normal reported values in this study are a basis for future studies of disease mechanisms involving oxidative stress and for future trials using antioxidant therapies for oxidative stress-related diseases in the pediatric field. 相似文献
123.
《Peptides》2016
Intermedin/adrenomedullin-2 (IMD) is a member of the adrenomedullin/CGRP peptide family. Less is known about the distribution of IMD than for other family members within the mammalian cardiovascular system, particularly in humans. The aim was to evaluate plasma IMD levels in healthy subjects and patients with chronic heart failure. IMD and its precursor fragments, preproIMD25–56 and preproIMD57–92, were measured by radioimmunoassay in 75 healthy subjects and levels of IMD were also compared to those of adrenomedullin (AM) and mid-region proadrenomedullin45–92 (MRproAM45–92) in 19 patients with systolic heart failure (LVEF < 45%). In healthy subjects, plasma levels (mean + SE) of IMD (6.3 + 0.6 pg ml−1) were lower than, but correlated with those of AM (25.8 + 1.8 pg ml−1; r = 0.49, p < 0.001). Plasma preproIMD25–56 (39.6 + 3.1 pg ml−1), preproIMD57–92 (25.9 + 3.8 pg ml−1) and MRproAM45–92 (200.2 + 6.7 pg ml−1) were greater than their respective bioactive peptides. IMD levels correlated positively with BMI but not age, and were elevated in heart failure (9.8 + 1.3 pg ml−1, p < 0.05), similarly to MRproAM45–92 (329.5 + 41.9 pg ml−1, p < 0.001) and AM (56.8 + 10.9 pg ml−1, p < 0.01). IMD levels were greater in heart failure patients with concomitant renal impairment (11.3 + 1.8 pg ml−1) than those without (6.5 + 1.0 pg ml−1; p < 0.05). IMD and AM were greater in patients receiving submaximal compared with maximal heart failure drug therapy and were decreased after 6 months of cardiac resynchronization therapy. In conclusion, IMD is present in the plasma of healthy subjects less abundantly than AM, but is similarly correlated weakly with BMI. IMD levels are elevated in heart failure, especially with concomitant renal impairment, and tend to be reduced by high intensity drug or pacing therapy. 相似文献
124.
Data on the structure and function of the yeastSaccharomyces cerevisiae genome are summarized. Hypotheses of the evolution of the yeast genome are considered. The methods used to establish the
function of earlier uncharacterized genes, to study the expression of the entire genome, and to analyze the yeast proteome
are described along with the first results of this work. The prospects of further development of yeast genetics in the postgenomic
era are discussed. 相似文献
125.
Effects of supramaximal exercise on blood glucose levels during a subsequent exercise 总被引:1,自引:0,他引:1
J. Y. Roy J. Bongbélé S. Cardin G. R. Brisson J. -M. Lavoie 《European journal of applied physiology and occupational physiology》1991,63(1):48-51
The purpose of the present investigation was to examine the effects of hyperglycemia induced by supramaximal exercise on blood glucose homeostasis during submaximal exercise following immediately after. Six men were subjected to three experimental situations; in two of these situations, 3 min of high-intensity exercise (corresponding to 112, SD 1% VO2max) was immediately followed by either a 60-min period of submaximal exercise (68, SD 2% VO2max) or a 60-min resting period. In the third situation, subjects performed a 63-min period of submaximal exercise only. There were no significant differences between the heart rates, oxygen uptakes, and respiratory exchange ratios during the two submaximal exercise bouts (greater than 15 min) whether or not preceded by supramaximal exercise. The supramaximal exercise was associated within 10 min of the start increases (P less than 0.05) in blood glucose, insulin, and lactate concentrations. This hyperglycemia was more pronounced when subjects continued to exercise submaximally than when they rested (at 7.5 min; P less than 0.05). There was a more rapid return to normal exercise blood glucose and insulin values during submaximal exercise compared with rest. The data show that the hyperinsulinemia following supramaximal exercise is corrected in between 10-30 min during submaximal exercise following immediately, suggesting that this exercise combination does not lead to premature hypoglycemia. 相似文献
126.
Patterns of Plant Invasions: A Case Example in Native Species Hotspots and Rare Habitats 总被引:3,自引:0,他引:3
Thomas J. Stohlgren Yuka Otsuki Cynthia A. Villa Michelle Lee Jayne Belnap 《Biological invasions》2001,3(1):37-50
Land managers require landscape-scale information on where exotic plant species have successfully established, to better guide
research, control, and restoration efforts. We evaluated the vulnerability of various habitats to invasion by exotic plant
species in a 100,000 ha area in the southeast corner of Grand Staircase-Escalante National Monument, Utah. For the 97 0.1-ha
plots in 11 vegetation types, exotic species richness (log10) was strongly negatively correlated to the cover of cryptobiotic soil crusts (r = −0.47, P < 0.001), and positively correlated to native species richness (r = 0.22, P < 0.03), native species cover (r = 0.23, P < 0.05), and total nitrogen in the soil (r = 0.40, P < 0.001). Exotic species cover was strongly positively correlated to exotic species richness (r = 0.68, P < 0.001). Only 6 of 97 plots did not contain at least one exotic species. Exotic species richness was particularly high in
locally rare, mesic vegetation types and nitrogen rich soils. Dry, upland plots (n = 51) had less than half of the exotic species richness and cover compared to plots (n = 45) in washes and lowland depressions that collect water intermittently. Plots dominated by trees had significantly greater
native and exotic species richness compared to plots dominated by shrubs. For the 97 plots combined, 33% of the variance in
exotic species richness could be explained by a positive relationship with total plant cover, and negative relationships with
the cover of cryptobiotic crusts and bare ground. There are several reasons for concern: (1) Exotic plant species are invading
hot spots of native plant diversity and rare/unique habitats. (2) The foliar cover of exotic species was greatest in habitats
that had been invaded by several exotic species.(3) Continued disturbance of fragile cryptobiotic crusts by livestock, people,
and vehicles may facilitate the further invasion of exotic plant species.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
127.
Human participants played a computer game in which choices among five alternatives were concurrently reinforced according to dependent random-ratio schedules. "Dependent" indicates that choices to any of the wedges activated the random-number generators governing reinforcers on all five alternatives. Two conditions were compared. In the hold condition, once scheduled, a reinforcer - worth a constant five points - remained available until it was collected. In the decay condition, point values decreased with intervening responses, i.e., rapid collection was differentially reinforced. Slopes of matching functions were higher in the decay than hold condition. However inter-subject variability was high in both conditions. 相似文献
128.
Jan Sundell Hanna Laine Matti Luotolahti Kari Kalliokoski Olli Raitakari Pirjo Nuutila Juhani Knuuti 《Obesity (Silver Spring, Md.)》2002,10(7):617-624
Objective: Obesity is associated with increased risk for cardiovascular diseases and peripheral endothelial dysfunction. We examined whether myocardial vasoreactivity and coronary‐flow response to insulin stimulation are altered in obesity. Research Methods and Procedures: Myocardial blood flow was quantitated in 10 obese men (body mass index, 33.6 ± 1.9 kg/m2) and 10 healthy matched non‐obese men (body mass index, 24.2 ± 1.9 kg/m2), using positron emission tomography and oxygen‐15‐labeled water. The measurements were performed basally and during adenosine infusion (140 μg/kg per minute), with or without simultaneous physiological (1 mU/kg per minute) and supraphysiological (5 mU/kg per minute) hyperinsulinemia. Results: Basal myocardial blood flow was not significantly different between obese and non‐obese subjects. Adenosine‐stimulated flow was blunted in obese (3.2 ± 0.6 mL/g per minute) when compared with non‐obese subjects (4.0 ± 1.1 mL/g per minute, p < 0.05). Simultaneous physiological hyperinsulinemia increased adenosine‐stimulated myocardial flow significantly in both groups (to 4.03 ± 1.24 and 4.85 ± 1.04 mL/g per minute in obese and non‐obese men, respectively; p < 0.05 vs. adenosine). Supraphysiological hyperinsulinemia further enhanced the adenosine‐stimulated flow in non‐obese subjects (to 5.56 ± 0.98 mL/g per minute; p < 0.05) but not in obese subjects. Discussion: Young obese, healthy men have reduced myocardial vasoreactivity, which may represent an early precursor of future coronary artery disease. Additionally, insulin‐induced enhancement of myocardial blood flow is blunted in obesity. Thus, endothelial dysfunction seems to also characterize myocardial vasculature of obese subjects. 相似文献
129.
Despite the deep sea being the largest habitat on Earth, there are just 77 population genetic studies of invertebrates (115 species) inhabiting non‐chemosynthetic ecosystems on the deep‐sea floor (below 200 m depth). We review and synthesize the results of these papers. Studies reveal levels of genetic diversity comparable to shallow‐water species. Generally, populations at similar depths were well connected over 100s–1,000s km, but studies that sampled across depth ranges reveal population structure at much smaller scales (100s–1,000s m) consistent with isolation by adaptation across environmental gradients, or the existence of physical barriers to connectivity with depth. Few studies were ocean‐wide (under 4%), and 48% were Atlantic‐focused. There is strong emphasis on megafauna and commercial species with research into meiofauna, “ecosystem engineers” and other ecologically important species lacking. Only nine papers account for ~50% of the planet's surface (depths below 3,500 m). Just two species were studied below 5,000 m, a quarter of Earth's seafloor. Most studies used single‐locus mitochondrial genes revealing a common pattern of non‐neutrality, consistent with demographic instability or selective sweeps; similar to deep‐sea hydrothermal vent fauna. The absence of a clear difference between vent and non‐vent could signify that demographic instability is common in the deep sea, or that selective sweeps render single‐locus mitochondrial studies demographically uninformative. The number of population genetics studies to date is miniscule in relation to the size of the deep sea. The paucity of studies constrains meta‐analyses where broad inferences about deep‐sea ecology could be made. 相似文献
130.
Miklós?SárospatakiEmail author Judit?Novák Viktória?Molnár 《Biodiversity and Conservation》2005,14(10):2437-2446
Decline in the populations of bumble bees and other pollinators stress the need for more knowledge about their conservation
status. Only one of the 25 bumble bee species present in Hungary is included in the Hungarian Red List. We estimated the endangerment
of the Hungarian bumble bee (Bombus Latr.) species using the available occurrence data from the last 50 years of the 20th century. Four of the 25 species were
data deficient or extinct from Hungary. About 60% of species were considered rare or moderately rare. Changes in distribution
and occurrence frequency indicated that 10 of the 21 native species showed a declining trend, while only three species increased
in frequency of occurrence. According to the IUCN Red List categories, seven species (33% of the native fauna) should be labelled
as critically endangered (CR) and 3 (14%) as endangered (EN). Our results stress an urgent need of protection plans for bumble
bees in Hungary, and further underlines the validity of concern over bumble bees all over Europe. 相似文献