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961.

Background

An estimated 120,000 HIV-associated cryptococcal meningitis (CM) cases occur each year in South and Southeast Asia; early treatment may improve outcomes. The World Health Organization (WHO) recently recommended screening HIV-infected adults with CD4<100 cells/mm3 for serum cryptococcal antigen (CrAg), a marker of early cryptococcal infection, in areas of high CrAg prevalence. We evaluated CrAg prevalence and cost-effectiveness of this screening strategy in HIV-infected adults in northern and southern Vietnam.

Methods

Serum samples were collected and stored during 2009–2012 in Hanoi and Ho Chi Minh City, Vietnam, from HIV-infected, ART-naïve patients presenting to care in 12 clinics. All specimens from patients with CD4<100 cells/mm3 were tested using the CrAg lateral flow assay. We obtained cost estimates from laboratory staff, clinicians and hospital administrators in Vietnam, and evaluated cost-effectiveness using WHO guidelines.

Results

Sera from 226 patients [104 (46%) from North Vietnam and 122 (54%) from the South] with CD4<100 cells/mm3 were available for CrAg testing. Median CD4 count was 40 (range 0–99) cells/mm3. Nine (4%; 95% CI 2–7%) specimens were CrAg-positive. CrAg prevalence was higher in South Vietnam (6%; 95% CI 3–11%) than in North Vietnam (2%; 95% CI 0–6%) (p = 0.18). Cost per life-year gained under a screening scenario was $190, $137, and $119 at CrAg prevalences of 2%, 4% and 6%, respectively.

Conclusion

CrAg prevalence was higher in southern compared with northern Vietnam; however, CrAg screening would be considered cost-effective by WHO criteria in both regions. Public health officials in Vietnam should consider adding cryptococcal screening to existing national guidelines for HIV/AIDS care.  相似文献   
962.

Introduction

This paper reports changes in behavioral outcomes related to the use of HIV testing service of a project that employed peer-based education strategies and integration of HIV voluntary counseling and testing (VCT) and Sexual and Reproductive Health (SRH) services targeting young people aged 15–24 across 5 provinces in Vietnam.

Methods

A pre-test/post-test, non-experimental evaluation design was used. Data were collected from cross-sectional surveys of youth and client exit interviews at project supported SRH clinics conducted at baseline and again at 24 months following implementation. The baseline samples consisted of 813 youth and 399 exit clients. The end line samples included 501 youths and 399 exit clients. Z test was used to assess changes in behavioral outcomes.

Results

Results show that there was a significant increase (p<0.05) in the percentage of youth who wanted to obtain a HIV test (from 33% to 51%), who had ever had a test (from 7.5% to 15%), and who had a repeat test in the last 12 months (from 54.5% to 67.5%). Exit client interviews found a nearly five-fold increase in the percentage of clients seeking HIV VCT in their current visit (5.0% vs. 24.5%) and almost two-fold increase in the percentage of those having their last test at a project supported clinic (9.3% vs. 17.8%). There were also positive changes in some aspects of youth HIV/AIDS knowledge, attitudes, and risk perceptions.

Conclusions

This study provides preliminary evidence regarding the benefits of the integration of HIV VCT-SRH services in terms of increased access to HIV services and testing in Vietnam. Benefits of peer-based education regarding increased HIV knowledge were also identified. Further investigations, including experimental studies with assessment of health outcomes and the uptake of HIV testing services, are required to better elucidate the effectiveness and challenges of this intervention model in Vietnam.  相似文献   
963.
Plants are able to interact with their environment by emitting volatile organic compounds. We investigated the volatile interactions that take place below ground between barley roots and two pathogenic fungi, Cochliobolus sativus and Fusarium culmorum. The volatile molecules emitted by each fungus, by non-infected barley roots and by barley roots infected with one of the fungi or the two of them were extracted by head-space solid phase micro extraction and analyzed by gas chromatography mass spectrometry. The effect of fungal volatiles on barley growth and the effect of barley root volatiles on fungal growth were assessed by cultivating both organisms in a shared atmosphere without any physical contact. The results show that volatile organic compounds, especially terpenes, are newly emitted during the interaction between fungi and barley roots. The volatile molecules released by non-infected barley roots did not significantly affect fungal growth, whereas the volatile molecules released by pathogenic fungi decreased the length of barley roots by 19 to 21.5% and the surface of aerial parts by 15%. The spectrum of the volatiles released by infected barley roots had no significant effect on F. culmorum growth, but decreased C. sativus growth by 13 to 17%. This paper identifies the volatile organic compounds emitted by two pathogenic fungi and shows that pathogenic fungi can modify volatile emission by infected plants. Our results open promising perspectives concerning the biological control of edaphic diseases.  相似文献   
964.
Leptin acts via neuronal leptin receptors to control energy balance. Hypothalamic pro-opiomelanocortin (POMC) and agouti-related peptide (AgRP)/Neuropeptide Y (NPY)/GABA neurons produce anorexigenic and orexigenic neuropeptides and neurotransmitters, and express the long signaling form of the leptin receptor (LepRb). Despite progress in the understanding of LepRb signaling and function, the sub-cellular localization of LepRb in target neurons has not been determined, primarily due to lack of sensitive anti-LepRb antibodies. Here we applied light microscopy (LM), confocal-laser scanning microscopy (CLSM), and electron microscopy (EM) to investigate LepRb localization and signaling in mice expressing a HA-tagged LepRb selectively in POMC or AgRP/NPY/GABA neurons. We report that LepRb receptors exhibit a somato-dendritic expression pattern. We further show that LepRb activates STAT3 phosphorylation in neuronal fibers within several hypothalamic and hindbrain nuclei of wild-type mice and rats, and specifically in dendrites of arcuate POMC and AgRP/NPY/GABA neurons of Leprb +/+ mice and in Leprb db/db mice expressing HA-LepRb in a neuron specific manner. We did not find evidence of LepRb localization or STAT3-signaling in axon-fibers or nerve-terminals of POMC and AgRP/NPY/GABA neurons. Three-dimensional serial EM-reconstruction of dendritic segments from POMC and AgRP/NPY/GABA neurons indicates a high density of shaft synapses. In addition, we found that the leptin activates STAT3 signaling in proximity to synapses on POMC and AgRP/NPY/GABA dendritic shafts. Taken together, these data suggest that the signaling-form of the leptin receptor exhibits a somato-dendritic expression pattern in POMC and AgRP/NPY/GABA neurons. Dendritic LepRb signaling may therefore play an important role in leptin’s central effects on energy balance, possibly through modulation of synaptic activity via post-synaptic mechanisms.  相似文献   
965.
The biotreatment of flue gases with algae cultures is a promising option to sequestrate CO2, yet the emission of other greenhouse gases (GHG) from the cultures can hamper their environmental benefit. Quantitative data on the sequestration potential for CO2 and NO x in relation to the direct production of CH4 and N2O are urgently required. The present study assessed the flows of carbon (C) and nitrogen (N) through cultures of the green alga Dunaliella salina, supplied with biodiesel flue gas, by means of mass balancing. D. salina was grown in artificially lighted, field- (42-L bubble column reactor) and laboratory-scale cultures (23 °C, pH 7.5). In the bubble column reactor, algae grew with an average specific growth rate of 0.237 day?1 under flue gas supplementation (6.3 % (v/v) CO2, 1.2 ppmv NO x ), and CO2 was retained to 39 % in the system. The specific sequestration rate for CO2 was low, with 0.13 g CO2 L?1 day?1. Cultures emitted up to 13.03 μg CH4 L?1 day?1 and 4261 μg N2O L?1 day?1. The moderate retention of NO x -N was outweighed by emissions of N2O-N, and total N in the system decreased by 15.48 % during the 9-day trial. Results suggest that GHG production was mainly the outcome of anaerobic microbial processes and their emission was lower in pre-sterilized cultures. Under the tested conditions, up to six times more CO2 equivalents were emitted during flue gas treatment. Therefore, the direct GHG emissions of algae culture systems, intended for flue gas treatment (i.e. open ponds) need to be reviewed critically.  相似文献   
966.
The macrophage scavenger receptor class A (SR-A) participates in the innate immune and inflammatory responses. This study examined the role of macrophage SR-A in myocardial ischemia/reperfusion (I/R) injury and hypoxia/reoxygenation (H/R)-induced cell damage. SR-A?/? and WT mice were subjected to ischemia (45 min) followed by reperfusion for up to 7 days. SR-A?/? mice showed smaller myocardial infarct size and better cardiac function than did WT I/R mice. SR-A deficiency attenuated I/R-induced myocardial apoptosis by preventing p53-mediated Bak-1 apoptotic signaling. The levels of microRNA-125b in SR-A?/? heart were significantly greater than in WT myocardium. SR-A is predominantly expressed on macrophages. To investigate the role of SR-A macrophages in H/R-induced injury, we isolated peritoneal macrophages from SR-A deficient (SR-A?/?) and wild type (WT) mice. Macrophages were subjected to hypoxia followed by reoxygenation. H/R markedly increased NF-κB binding activity as well as KC and MCP-1 production in WT macrophages but not in SR-A?/? macrophages. H/R induced caspase-3/7 and -8 activities and cell death in WT macrophages, but not in SR-A?/? macrophages. The levels of miR-125b in SR-A?/? macrophages were significantly higher than in WT macrophages. Transfection of WT macrophages with miR-125b mimics attenuated H/R-induced caspase-3/7 and -8 activities and H/R-decreased viability, and prevented H/R-increased p-53, Bak-1 and Bax expression. The data suggest that SR-A deficiency attenuates myocardial I/R injury by targeting p53-mediated apoptotic signaling. SR-A?/? macrophages contain high levels of miR-125b which may play a role in the protective effect of SR-A deficiency on myocardial I/R injury and H/R-induced cell damage.  相似文献   
967.
Accelerated growth in early infancy has been associated with later cardiovascular and metabolic diseases. We investigated the influence of overnutrition during neonatal periods on the development of renal pathophysiological changes in adult offspring rats. Three or 10 male pups per mother were assigned to either the small litter (SL) or normal litter (NL) control groups during the first 21 days of life. The effects of early postnatal overnutrition on body weight, blood pressure and renal changes were determined at 3 and 6 months. Pups in the SL group weighed more than controls between 7 days and 6 months of age (P<.05). In the SL group, serum creatinine levels were higher at 3 and 6 months (P<.05), and at 6 months, blood pressure levels were higher than those of the controls (P<.05). The number of ED-1 positive macrophages in renal cortex and glomerulosclerosis index increased in the SL group at 3 and 6 months (P<.05). Additionally, cortical apoptotic cells increased in the SL group at 6 months (P<.05). Immunoblotting and immunohistochemistry showed that matrix metalloproteinase (MMP)-9 protein expressions decreased and tissue inhibitor of MMP-1, tumor necrosis factor-α, osteopontin and adiponectin expressions increased in the SL group at 3 months (P<.05). However, at 6 months, MMP-9 expression was elevated, and osteopontin expression remained elevated in the SL group (P<.05). Early postnatal overfeeding can lead to lasting overweight, hypertension and renal dysfunction and place a greater burden on the kidney.  相似文献   
968.
969.
Introduction: The correlation between alveolar nitric oxide (CANO) and the severity of interstitial lung disease (ILD) evaluated by high resolution computed tomography (HRCT) has not been well demonstrated. Methods: It was a perspective and observational study, including patients with diagnosed systemic sclerosis (SSc). They performed lung function testing (LFT), exhaled nitric oxide (NO) measurements, exercise testing, chest X-ray, and HRCT. Study patients were divided into SSc with ILD (SSc-ILD+) or without ILD (SSc-ILD-). SSC-ILD+ patients were revisited after 6 months and 12 months to complete the study. Results: Thirty-one control subjects and 74 patients with SSc (33 SSc-ILD- and 41 SSc-ILD+) were included. Forty-one SSc-ILD+ patients were followed-up at 6 months and 12 months. Lung functional parameters of patients with SSc-ILD+ were lower than that of SSc-ILD- patients. The level of CANO was significantly higher in SSc-ILD+ than SSc-ILD- patients (8.6 ± 2.5 vs 4.2 ± 1.3 ppb and P<0.01). Warrick and Goldin scores of patients with SSc-ILD+ were respectively 16.5 ± 5.2 and 12.7 ± 4.3. Warrick scores were reduced after 6 and 12 months of follow-up vs at inclusion (12.4 ± 4.3 and 9.1 ± 3.2 vs 16.5 ± 5.2; P<0.05, P<0.01, and P<0.05; respectively). ΔWarrick and ΔGoldin scores were significantly and inversely correlated with ΔFVC, ΔTLC, ΔTLCO, ΔVO2 max; that was also correlated with ΔCANO (R= 0.783, P<0.01 and R= 0.719 and P<0.05). Conclusion: CANO is a relevant biomarker for the diagnosis of ILD in patients with SSc, especially in combination with HRCT.  相似文献   
970.
Cytomegalovirus (CMV) infection is associated with Pneumocystis jirovecii pneumonia (PJP) in kidney transplant recipients (KTRs), but its impact on clinical severity and outcomes in KTRs with PJP is unknown. We reviewed 1994 medical records of KTRs from January 1997 to March 2019. PJP or CMV infection was diagnosed by polymerase chain reaction or culturing using blood or respiratory specimens. We divided patients into PJP and PJP+CMV groups, and evaluated the clinical severity and outcomes. Fifty two patients had PJP (2.6%) in the whole study cohort. Among patients with PJP, 38 (73.1%) had PJP alone and 14 (26.9%) had combined PJP and CMV co-infection. The PJP+CMV group showed worse laboratory findings (serum albumin and C-reactive protein, P = 0.010 for both) and higher requirement of continuous renal replacement therapy than the PJP group (P = 0.050). The pneumonia severity was worse in the PJP+CMV group than in the PJP group (P < 0.05), and CMV infection was a high risk factor of pneumonia severity (odds ratio 16.0; P = 0.002). The graft function was worse in the PJP+CMV group (P < 0.001), and the incidence of graft failure was higher in the PJP+CMV group than in the PJP group (85.7% vs 36.8%; P < 0.001). Mortality was double in the PJP+CMV group than in the PJP group, but not statistically significant (21.4% vs 10.5%; P = 0.370). Our results show that approximately one in four patients with PJP after kidney transplantation develops CMV with increased clinical severity and risk of graft failure. The possibility of increased clinical severity and worse clinical outcomes by CMV co-infection should be considered in KTRs with PJP.  相似文献   
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