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BackgroundUnder nutrition is a problem of severe magnitude in low income countries like Nigeria. Adolescent school children might also be vulnerable. The dearth of data hinders planning of school health and nutrition programmes for school children.ObjectiveTo determine the prevalence of stunting, thinness; vitamin A and iron deficiencies among adolescent students in Nsukka urban, Nigeria and to determine factors that are associated with these nutritional problems.MethodsA total of 400 participants were randomly selected from 717 students aged 12 – 18 years in 3 randomly selected secondary schools. Questionnaires, anthropometric measurements, and blood analyses were the data collection methods employed.ResultsThe prevalence of stunting was 33.3% and thinness 31.0%. Neither overweight nor obesity was observed. While 64.0% were anaemic; 44.0% had vitamin A deficiency (VAD). A total of 48.0% had both anaemia and stunting, 42% had VAD + thinness; while 40% had anaemia + VAD. Household income was a predictor of vitamin A status. Children from medium/high income households had higher odds of having VAD than those from low income households (AOR=0.14; 95% CI=0.031, 0.607; P=0.009). Household income (AOR=0.12; 95% CI=0.021, 0.671; P=0.016), and age (AOR=0.09; 95% CI=0.014, 0.587; P=0.012) were independent determinants of height-for-age status.ConclusionAmong urban adolescent students in Nigeria, stunting, thinness, anaemia and VAD were problems of public health significance. Age and household monthly income played major roles.  相似文献   
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Despite successful control of viremia, many HIV-infected individuals given antiretroviral therapy (ART) exhibit residual inflammation, which is associated with non–AIDS-related morbidity and mortality and may contribute to virus persistence during ART. Here, we investigated the effects of IL-21 administration on both inflammation and virus persistence in ART-treated, SIV-infected rhesus macaques (RMs). Compared with SIV-infected animals only given ART, SIV-infected RMs given both ART and IL-21 showed improved restoration of intestinal Th17 and Th22 cells and a more effective reduction of immune activation in blood and intestinal mucosa, with the latter maintained through 8 months after ART interruption. Additionally, IL-21, in combination with ART, was associated with reduced levels of SIV RNA in plasma and decreased CD4+ T cell levels harboring replication-competent virus during ART. At the latest experimental time points, which were up to 8 months after ART interruption, plasma viremia and cell-associated SIV DNA levels remained substantially lower than those before ART initiation in IL-21–treated animals but not in controls. Together, these data suggest that IL-21 supplementation of ART reduces residual inflammation and virus persistence in a relevant model of lentiviral disease and warrants further investigation as a potential intervention for HIV infection.  相似文献   
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Introduction

Within monocyte-derived macrophages, HIV-1 accumulates in intracellular virus-containing compartments (VCCs) that are inaccessible to the external environment, which implicate these cells as latently infected HIV-1 reservoirs. During mother-to-child transmission of HIV-1, human placental macrophages (Hofbauer cells (HCs)) are viral targets, and have been shown to be infected in vivo and sustain low levels of viral replication in vitro; however, the risk of in utero transmission is less than 7%. The role of these primary macrophages as viral reservoirs is largely undefined. The objective of this study is to define potential sites of viral assembly, accumulation and neutralization in HCs given the pivotal role of the placenta in preventing HIV-1 infection in the mother-infant dyad.

Methods

Term placentae from 20 HIV-1 seronegative women were obtained following caesarian section. VCCs were evaluated by 3D confocal and electron microscopy. Colocalization R values (Pearson''s correlation) were quantified with colocalization module of Volocity 5.2.1. Replication kinetics and neutralization studies were evaluated using p24 ELISA.

Results

We demonstrate that primary HCs assemble and sequester HIV-1BaL in intracellular VCCs, which are enriched in endosomal/lysosomal markers, including CD9, CD81, CD63 and LAMP-1. Following infection, we observed HIV-1 accumulation in potentially acidic compartments, which stained intensely with Lysotracker-Red. Remarkably, these compartments are readily accessible via the cell surface and can be targeted by exogenously applied small molecules and HIV-1-specific broadly neutralizing antibodies. In addition, broadly neutralizing antibodies (4E10 and VRC01) limited viral replication by HIV-1-infected HCs, which may be mediated by FcγRI.

Conclusions

These findings suggest that placental HCs possess intrinsic adaptations facilitating unique sequestration of HIV-1, and may serve as a protective viral reservoir to permit viral neutralization and/or antiretroviral drug entry in utero.  相似文献   
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Macrocyclic chemistry is one of the emerging research areas in the chemical science. Macrocyclic compounds continue to attract significant attention due to their numerous possible applications particularly in the areas like biology, catalysis and industry. This review article summarizes the developments and advances in synthesis and medicinal applications of macrocyclic compounds derived from (benz)imidazole‐ and indole‐based heterocycles. Important medicinal applications of (benz)imidazole‐ and indole‐based macrocycles include antimicrobial and anticancer activities. The representative lead compounds in each series of macromolecules have been discussed. All these initial lead breakthroughs help validate the great potential of (benz)imidazole‐ and indole‐based macrocyclic compounds as a class of effective medicinal agents.  相似文献   
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Cerebrospinal fluid (CSF) drains via the lymphatic drainage pathway. This lymphatic pathway connects the central nervous system (CNS) to the cervical lymph node (CLN). As the CSF drains to CLN via the dural and nasal lymphatics, T cells and antigen presenting cells pass along the channels from the subarachnoid space through the cribriform plate. Human immunodeficiency virus (HIV) may also egress from the CNS along this pathway. As a result, HIV egressing from the CNS may accumulate within the CLN. Towards this objective, we analyzed CLNs isolated from rhesus macaques that were chronically-infected with simian immunodeficiency virus (SIV). We detected significant accumulation of SIV within the CLNs. SIV virion trapping was observed on follicular dendritic cells (FDCs) localized within the follicular regions of CLNs. In addition, SIV antigens formed immune complexes when FDCs interacted with B cells within the germinal centers. Subsequent interaction of these B cells with CD4+ T follicular helper cells (TFHs) resulted in infection of the latter. Of note, 73% to 90% of the TFHs cells within CLNs were positive for SIV p27 antigen. As such, it appears that not only do the FDCs retain SIV they also transmit them (via B cells) to TFHs within these CLNs. This interaction results in infection of TFHs in the CLNs. Based on these observations, we infer that FDCs within the CLNs have a novel role in SIV entrapment with implications for viral trafficking.  相似文献   
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目的:制备大鼠在体缺血再灌注模型,观察缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性的变化。方法:实验于2005-03/2006-10在解放军沈阳军区总医院医学实验动物中心和全军心血管研究所实验室完成。实验分组:选用健康雌性SD大鼠36只,根据预适应程序分为第1,2,3次缺血,第1,2,3次再灌注,每一时间点6只大鼠。实验过程:用手术套管法造成左冠状动脉主干缺血及再灌注。所有实验动物在实验程序结束后,取出心脏迅速置液氮保存备用。实验评估:用放射免疫法测环磷酸腺苷水平,生化法测环磷酸腺苷依赖蛋白激酶活性变化。结果:36只大鼠均进入结果分析。①环磷酸腺苷含量:第1次再灌注组低于第1次缺血组[(0.325±0.015),(0.395±0.024)pmol/g,t=6.06,P<0.001],第2次再灌注组低于第2次缺血组[(0.523±0.017),(0.708±0.067)pmol/g,t=6.56,P<0.001],第3次再灌注组低于第3次缺血组[(0.567±0.031),(0.712±0.038)pmol/g,t=7.24,P<0.001]。②环磷酸腺苷依赖蛋白激酶活性:第1次再灌注组低于第1次缺血组[(10.115±1.000),(16.351±0.849)pkat/g,t=11.12,P<0.001],第2次再灌注组低于第2次缺血组[(11.877±2.213),(14.869±0.619)pkat/g,t=3.31,P<0.01],第3次再灌注组低于第3次缺血组[(11.745±0.987),(14.766±0.329)pkat/g,t=7.09,P<0.001]。③缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性随缺血及再灌注呈周期性波动。在5min缺血预处理时表现为明显增高,而在间隔的再灌注程序中恰呈相反改变,有明显下降的趋势。结论:环磷酸腺苷及环磷酸腺苷依赖蛋白激酶的周期性波动变化可能是激发心肌缺血预处理的机制之一,环磷酸腺苷可能在预处理保护作用中起一些作用。  相似文献   
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The perinatal brain requires a tightly regulated iron transport system. Iron regulatory proteins (IRPs) 1 and 2 are cytosolic proteins that regulate the stability of mRNA for the two major cellular iron transporters, transferrin receptor (TfR) and divalent metal transporter-1 (DMT-1). We studied the localization of IRPs, their change in expression during perinatal development, and their relationship to TfR and DMT-1 in rat brain between postnatal days (PND) 5 and 15. Twelve-micron frozen coronal sections of fixed brain tissue were obtained from iron-sufficient Sprague-Dawley rat pups on PND 5, 10, and 15, and were visualized at 20 to 1,000x light microscopy for diaminobenzidine activity after incubation with specific primary IRP-1, IRP-2, DMT-1, and TfR antibodies and a universal biotinylated secondary and tertiary antibody system. IRP and transport protein expression increased in parallel over time. IRP1, IRP2, and DMT-1 were partially expressed in the choroid plexus epithelial cells at PND 5 and 10, and fully expressed at PND 15. The cerebral blood vessels and ependymal cells strongly expressed IRP1, IRP2, and DMT-1 as early as PND 5. Substantive TfR staining was not seen in the choroid plexus or ependyma until PND 15. Glial and neuronal expression of IRP1, IRP2, DMT-1, and TfR in cortex, hippocampal subareas and striatum increased over time, but showed variability in cell number and intensity of expression based on brain region, cell type, and age. These developmental changes in IRP and transporter expression suggest potentially different time periods of brain structure vulnerability to iron deficiency or iron overload.  相似文献   
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