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151.
20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE), a product of the cytochrome P450 (CYP)-catalyzed ω-hydroxylation of arachidonic acid, induces oxidative stress and, in clinical studies, is associated with increased body mass index (BMI) and the metabolic syndrome. This study was designed to examine the effects of exogenous 20-HETE on mesenchymal stem cell (MSC)-derived adipocytes. The expression levels of CYP4A11 and CYP4F2 (major 20-HETE synthases in humans) in MSCs decreased during adipocyte differentiation; however, exogenous administration of 20-HETE (0.1–1 μM) increased adipogenesis in a dose-dependent manner in these cells (P < 0.05). The inability of a 20-HETE analog to reproduce these effects suggested the involvement of a metabolic product of 20-HETE in mediating its pro-adipogenic effects. A cyclooxygenase (COX)-1 selective inhibitor enhanced, whereas a COX-2 selective or a dual COX-1/2 inhibitor attenuated adipogenesis induced by 20-HETE. The COX-derived metabolite of 20-HETE, 20-OH-PGE2, enhanced adipogenesis and lipid accumulation in MSCs. The pro-adipogenic effects of 20-HETE and 20-OH-PGE2 resulted in the increased expression of the adipogenic regulators PPARγ and β-catenin in MSC-derived adipocytes. Taken together we show for the first time that 20-HETE-derived COX-2-dependent 20-OH-PGE2 enhances mature inflamed adipocyte hypertrophy in MSC undergoing adipogenic differentiation.  相似文献   
152.

Background

Pregnancy-related (PR) deaths are often a result of direct obstetric complications occurring at childbirth.

Methods and Findings

To estimate the burden of and characterize risk factors for PR mortality, we evaluated deaths that occurred between 2003 and 2008 among women of childbearing age (15 to 49 years) using Health and Demographic Surveillance System data in rural western Kenya. WHO ICD definition of PR mortality was used: “the death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the cause of death”. In addition, symptoms and events at the time of death were examined using the WHO verbal autopsy methodology. Deaths were categorized as either (i) directly PR: main cause of death was ascribed as obstetric, or (ii) indirectly PR: main cause of death was non-obstetric. Of 3,223 deaths in women 15 to 49 years, 249 (7.7%) were PR. One-third (34%) of these were due to direct obstetric causes, predominantly postpartum hemorrhage, abortion complications and puerperal sepsis. Two-thirds were indirect; three-quarters were attributable to human immunodeficiency virus (HIV/AIDS), malaria and tuberculosis. Significantly more women who died in lower socio-economic groups sought care from traditional birth attendants (p = 0.034), while less impoverished women were more likely to seek hospital care (p = 0.001). The PR mortality ratio over the six years was 740 (95% CI 651–838) per 100,000 live births, with no evidence of reduction over time (χ2 linear trend = 1.07; p = 0.3).

Conclusions

These data supplement current scanty information on the relationship between infectious diseases and poor maternal outcomes in Africa. They indicate low uptake of maternal health interventions in women dying during pregnancy and postpartum, suggesting improved access to and increased uptake of skilled obstetric care, as well as preventive measures against HIV/AIDS, malaria and tuberculosis among all women of childbearing age may help to reduce pregnancy-related mortality.  相似文献   
153.
The genome of Arabidopsis has been searched for sequences of genes involved in acyl lipid metabolism. Over 600 encoded proteins have been identified, cataloged, and classified according to predicted function, subcellular location, and alternative splicing. At least one-third of these proteins were previously annotated as "unknown function" or with functions unrelated to acyl lipid metabolism; therefore, this study has improved the annotation of over 200 genes. In particular, annotation of the lipolytic enzyme group (at least 110 members total) has been improved by the critical examination of the biochemical literature and the sequences of the numerous proteins annotated as "lipases." In addition, expressed sequence tag (EST) data have been surveyed, and more than 3,700 ESTs associated with the genes were cataloged. Statistical analysis of the number of ESTs associated with specific cDNA libraries has allowed calculation of probabilities of differential expression between different organs. More than 130 genes have been identified with a statistical probability > 0.95 of preferential expression in seed, leaf, root, or flower. All the data are available as a Web-based database, the Arabidopsis Lipid Gene database (http://www.plantbiology.msu.edu/lipids/genesurvey/index.htm). The combination of the data of the Lipid Gene Catalog and the EST analysis can be used to gain insights into differential expression of gene family members and sets of pathway-specific genes, which in turn will guide studies to understand specific functions of individual genes.  相似文献   
154.
Aging in all organisms is inevitable. Male age can have profound effects on mating success and female reproduction, yet relatively little is known on the effects of male age on different components of the ejaculate. Furthermore, in mass‐reared insects used for the Sterile Insect Technique, there are often behavioral differences between mass‐reared and wild males, while differences in the ejaculate have been less studied. The ejaculate in insects is composed mainly of sperm and accessory gland proteins. Here, we studied how male age and strain affected (i) protein quantity of testes and accessory glands, (ii) the biological activity of accessory gland products injected into females, (iii) sperm viability, and (iv) sperm quantity stored by females in wild and mass‐reared Anastrepha ludens (Diptera: Tephritidae). We found lower protein content in testes of old wild males and lower sperm viability in females mated with old wild males. Females stored more sperm when mated to young wild males than with young mass‐reared males. Accessory gland injections of old or young males did not inhibit female remating. Knowledge of how male age affects different ejaculate components will aid our understanding on investment of the ejaculate and possible postcopulatory consequences on female behavior.  相似文献   
155.
The annual histological changes in ovarian morphology (oogenesis, follicular atresia, and corpus luteum) are described for the Mexican lizard Sceloporus grammicus, in two populations that inhabit contrasting environments (vegetation categories, climate, precipitation, and temperature) from Hidalgo State, Mexico. Two germinal beds were situated on the dorsal surface of each ovary of this species. In both the populations, oogenesis involves two major processes: previtellogenesis and vitellogenesis. The histological changes during previtellogenesis are similar to those for other reptilian sauropsids, whereas vitellogenesis differs and the features of this last process are described for the first time. In early previtellogenesis, primary oocytes have fibrillar chromosomes and the ooplasm stains slightly. The primordial follicles are surrounded by a granulosa composed of cuboidal follicular cells. During late previtellogenesis, the oocyte had an eccentric nucleus with lamp‐brush chromosomes and multiple nucleoli. The granulosa becomes multilayered and polymorphic, containing three cell types: small, intermediate, and pyriform. The zona pellucida was homogeneous and clearly observed. In early vitellogenesis, the oocyte showed several small acidophilic granules distributed in the center and the periphery of the oocyte. As vitellogenesis progresses, the yolk platelets move toward the central area of the oocyte and they fuse to form acidophilic and homogeneous yolk. Lipid droplets were distributed irregularly in the ooplasm of the oocyte. In Zacualtipán, the results revealed a strong seasonal reproductive activity. Females had vitellogenic follicles from July to September, and pregnant females were founded from September to March. In Tizayuca, the results showed an unusual pattern of reproductive activity. Females with vitellogenic follicles and pregnant females were found throughout the year, indicating continuous reproduction. We suggest that the observed differences in reproductive activity from these populations indicate adaptative fine tuning in response to local environmental conditions. These results contribute to the knowledge of variation in vitellogenesis and reproductive strategies of this species and among spiny lizards overall. J. Morphol. 275:949–960, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
156.
The plant hormone jasmonate (JA) controls diverse aspects of plant immunity, growth, and development. The amplitude and duration of JA responses are controlled in large part by the intracellular level of jasmonoyl-l-isoleucine (JA-Ile). In contrast to detailed knowledge of the JA-Ile biosynthetic pathway, little is known about enzymes involved in JA-Ile metabolism and turnover. Cytochromes P450 (CYP) 94B3 and 94C1 were recently shown to sequentially oxidize JA-Ile to hydroxy (12OH-JA-Ile) and dicarboxy (12COOH-JA-Ile) derivatives. Here, we report that a third member (CYP94B1) of the CYP94 family also participates in oxidative turnover of JA-Ile in Arabidopsis. In vitro studies showed that recombinant CYP94B1 converts JA-Ile to 12OH-JA-Ile and lesser amounts of 12COOH-JA-Ile. Consistent with this finding, metabolic and physiological characterization of CYP94B1 loss-of-function and overexpressing plants demonstrated that CYP94B1 and CYP94B3 coordinately govern the majority (>95%) of 12-hydroxylation of JA-Ile in wounded leaves. Analysis of CYP94-promoter-GUS reporter lines indicated that CYP94B1 and CYP94B3 serve unique and overlapping spatio-temporal roles in JA-Ile homeostasis. Subcellular localization studies showed that CYP94s involved in conversion of JA-Ile to 12COOH-JA-Ile reside on endoplasmic reticulum (ER). In vitro studies further showed that 12COOH-JA-Ile, unlike JA-Ile, fails to promote assembly of COI1-JAZ co-receptor complexes. The double loss-of-function mutant of CYP94B3 and ILL6, a JA-Ile amidohydrolase, displayed a JA profile consistent with the collaborative action of the oxidative and the hydrolytic pathways in JA-Ile turnover. Collectively, our results provide an integrated view of how multiple ER-localized CYP94 and JA amidohydrolase enzymes attenuate JA signaling during stress responses.  相似文献   
157.

Background

Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended for malaria prevention in HIV-negative pregnant women, but it is contraindicated in HIV-infected women taking daily cotrimoxazole prophylaxis (CTXp) because of potential added risk of adverse effects associated with taking two antifolate drugs simultaneously. We studied the safety and efficacy of mefloquine (MQ) in women receiving CTXp and long-lasting insecticide treated nets (LLITNs).

Methods and Findings

A total of 1,071 HIV-infected women from Kenya, Mozambique, and Tanzania were randomized to receive either three doses of IPTp-MQ (15 mg/kg) or placebo given at least one month apart; all received CTXp and a LLITN. IPTp-MQ was associated with reduced rates of maternal parasitemia (risk ratio [RR], 0.47 [95% CI 0.27–0.82]; p = 0.008), placental malaria (RR, 0.52 [95% CI 0.29–0.90]; p = 0.021), and reduced incidence of non-obstetric hospital admissions (RR, 0.59 [95% CI 0.37–0.95]; p = 0.031) in the intention to treat (ITT) analysis. There were no differences in the prevalence of adverse pregnancy outcomes between groups. Drug tolerability was poorer in the MQ group compared to the control group (29.6% referred dizziness and 23.9% vomiting after the first IPTp-MQ administration). HIV viral load at delivery was higher in the MQ group compared to the control group (p = 0.048) in the ATP analysis. The frequency of perinatal mother to child transmission of HIV was increased in women who received MQ (RR, 1.95 [95% CI 1.14–3.33]; p = 0.015). The main limitation of the latter finding relates to the exploratory nature of this part of the analysis.

Conclusions

An effective antimalarial added to CTXp and LLITNs in HIV-infected pregnant women can improve malaria prevention, as well as maternal health through reduction in hospital admissions. However, MQ was not well tolerated, limiting its potential for IPTp and indicating the need to find alternatives with better tolerability to reduce malaria in this particularly vulnerable group. MQ was associated with an increased risk of mother to child transmission of HIV, which warrants a better understanding of the pharmacological interactions between antimalarials and antiretroviral drugs.

Trial registration

ClinicalTrials.gov NCT 00811421; Pan African Clinical Trials Registry PACTR 2010020001813440 Please see later in the article for the Editors'' Summary  相似文献   
158.

Background

In the northwest of Ethiopia, at the South Gondar region, there was a visceral leishmaniasis (VL) outbreak in 2005, making the disease a public health concern for the regional health authorities ever since. The knowledge on how the population perceives the disease is essential in order to propose successful control strategies.

Methodology/Principal findings

Two surveys on VL knowledge, attitudes and practices were conducted at the beginning (May 2009) and at the end (February 2011) of a VL longitudinal study carried out in rural communities of Libo Kemkem and Fogera, two districts of the Amhara Regional State. Results showed that VL global knowledge was very low in the area, and that it improved substantially in the period studied. Specifically, from 2009 to 2011, the frequency of proper knowledge regarding VL signs and symptoms increased from 47% to 71% (p<0.0001), knowledge of VL causes increased from 8% to 25% (p<0.0001), and knowledge on VL protection measures from 16% to 55% (p<0.0001). Moreover, the improvement observed in VL knowledge was more marked among the families with no previous history of VL case. Finally, in 2011 more than 90% of the households owned at least an impregnated bed net and had been sprayed, and attitudes towards these and other protective measures were very positive (over 94% acceptance for all of them).

Conclusions/Significance

In 2009 the level of knowledge regarding VL was very low among the rural population of this area, although it improved substantially in the study period, probably due to the contribution of many actors in the area. VL patients and relatives should be appropriately informed and trained as they may act as successful health community agents. VL risk behavioural patterns are subject to change as attitudes towards protective measures were very positive overall.  相似文献   
159.
In this study we developed, characterized and validated in vitro a functional superparagmagnetic iron-oxide based magnetic resonance contrast agent by conjugating a commercially available iron oxide nanoparticle, Molday ION Rhodamine-B Carboxyl (MIRB), with a deimmunized mouse monoclonal antibody (muJ591) targeting prostate-specific membrane antigen (PSMA). This functional contrast agent is intended for the specific and non-invasive detection of prostate cancer cells that are PSMA positive, a marker implicated in prostate tumor progression and metastasis. The two-step carbodiimide reaction used to conjugate the antibody to the nanoparticle was efficient and we obtained an elemental iron content of 1958±611 per antibody. Immunofluorescence microscopy and flow cytometry showed that the conjugated muJ591:MIRB complex specifically binds to PSMA-positive (LNCaP) cells. The muJ591:MIRB complex reduced cell adhesion and cell proliferation on LNCaP cells and caused apoptosis as tested by Annexin V assay, suggesting anti-tumorigenic characteristics. Measurements of the T2 relaxation time of the muJ591:MIRB complex using a 400 MHz Innova NMR and a multi-echo spin-echo sequence on a 3T MRI (Achieva, Philips) showed a significant T2 relaxation time reduction for the muJ591:MIRB complex, with a reduced T2 relaxation time as a function of the iron concentration. PSMA-positive cells treated with muJ591:MIRB showed a significantly shorter T2 relaxation time as obtained using a 3T MRI scanner. The reduction in T2 relaxation time for muJ591:MIRB, combined with its specificity against PSMA+LNCaP cells, suggest its potential as a biologically-specific MR contrast agent.  相似文献   
160.

Background

India has a high burden of drug resistant TB, although there are few data on XDR-TB. Although XDR-TB has existed previously in India, the definition has not been widely applied, and surveillance using second line drug susceptibility testing has not been performed. Our objective was to analyze clinical and demographic risk factors associated with isolation of MDR and XDR TB as compared to susceptible controls, at a tertiary center.

Methodology/Findings

Retrospective chart review based on positive cultures isolated in a high volume mycobacteriology laboratory between 2002 and 2007. 47 XDR, 30 MDR and 117 susceptible controls were examined. Drug resistant cases were less likely to be extrapulmonary, and had received more previous treatment regimens. Significant risk factors for XDR-TB included residence outside the local state (OR 7.43, 3.07-18.0) and care costs subsidized (OR 0.23, 0.097-0.54) in bivariate analysis and previous use of a fluoroquinolone and injectable agent (other than streptomycin) (OR 7.00, 95% C.I. 1.14-43.03) and an initial treatment regimen which did not follow national guidelines (OR 5.68, 1.24-25.96) in multivariate analysis. Cavitation and HIV did not influence drug resistance.

Conclusions/Significance

There is significant selection bias in the sample available. Selection pressure from previous treatment and an inadequate initial regimen increases risk of drug resistance. Local patients and those requiring financial subsidies may be at lower risk of XDR-TB.  相似文献   
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