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101.
A longitudinal community-trial on the control of soil-transmitted helminths (STHs), as part of a lymphatic filariasis elimination campaign, was taken up in two revenue blocks of southern India in the years 2001 and 2002 to assess the impact of two annual single-dose mass drug administration (MDA) of diethylcarbamazine (DEC) + albendazole (ALB) with that of DEC alone. The prevalences and intensities of STHs were studied among cross-sectional samples of school children aged 9-10 years by using the Kato-Katz technique at baseline and 11 months after each MDA. The combined drug mass treatment produced a higher reduction in the prevalence (RIP) (51-77%) and the egg reduction rate (ERR) (92-98%) compared with 12-15% RIP and 58-62% ERR of DEC alone mass treatment. The effect of two-drug therapy after two annual treatments was relatively long lasting as shown by RIP and ERR indicating that the reinfection rates were relatively lower in this approach than single-drug therapy. This study demonstrates that mass drug co-administration of DEC + ALB in Global Programme for Elimination of Lymphatic Filariasis (GPELF) targeted at the community had a synergistic and sustainable effect against soil-transmitted helminthiasis and provided considerable 'beyond filariasis' benefits. The additional advantages accrued to the community underscore the importance of scaling-up GPELF to cover the entire population at risk.  相似文献   
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Pulmonary artery aneurysm (PAA) secondary to Beh?et's disease (BD) is a rare condition. The commonest presentation is hemoptysis, which can be fatal. Though the classical triad of recurrent oral and genital ulcers and relapsing iritis is present in most patients of BD, isolated pulmonary artery involvement termed as incomplete BD has been reported. Prompt diagnosis and immunosuppressive therapy can cause regression of aneurysm and prevent fatal hemoptysis. We report a case of PAA due to BD who presented with hemoptysis and responded to steroid therapy.  相似文献   
105.
In 2012, the United Nations estimated that globally, 34 million people were living with human immunodeficiency virus (HIV) infection at the end of 2011.  相似文献   
106.
A novel strategy towards the synthesis of 1,4-disubstituted 1,2,3-triazoles via C–N and N–N bond formation has been demonstrated under transition metal-free and azide-free conditions. These 1,2,3-triazoles were obtained in a regioselective manner from commercially available anilines, aryl alkenes/aryl alkynes and N-tosylhydrazines using I2 under O2 atmosphere. Broad substrate scope, milder reaction conditions, good to moderate yields and clean protocol are the notable features of the method. Moreover, this protocol is amenable for the generation of a library of medicinally important key building blocks.

A novel strategy towards the synthesis of 1,4-disubstituted 1,2,3-triazoles via C–N and N–N bond formation has been demonstrated under transition metal-free and azide-free conditions.  相似文献   
107.
Mitochondria cannot form de novo but require mechanisms allowing their inheritance to daughter cells. In contrast to most other eukaryotes Trypanosoma brucei has a single mitochondrion whose single-unit genome is physically connected to the flagellum. Here we identify a β-barrel mitochondrial outer membrane protein, termed tripartite attachment complex 40 (TAC40), that localizes to this connection. TAC40 is essential for mitochondrial DNA inheritance and belongs to the mitochondrial porin protein family. However, it is not specifically related to any of the three subclasses of mitochondrial porins represented by the metabolite transporter voltage-dependent anion channel (VDAC), the protein translocator of the outer membrane 40 (TOM40), or the fungi-specific MDM10, a component of the endoplasmic reticulum–mitochondria encounter structure (ERMES). MDM10 and TAC40 mediate cellular architecture and participate in transmembrane complexes that are essential for mitochondrial DNA inheritance. In yeast MDM10, in the context of the ERMES, is postulated to connect the mitochondrial genomes to actin filaments, whereas in trypanosomes TAC40 mediates the linkage of the mitochondrial DNA to the basal body of the flagellum. However, TAC40 does not colocalize with trypanosomal orthologs of ERMES components and, unlike MDM10, it regulates neither mitochondrial morphology nor the assembly of the protein translocase. TAC40 therefore defines a novel subclass of mitochondrial porins that is distinct from VDAC, TOM40, and MDM10. However, whereas the architecture of the TAC40-containing complex in trypanosomes and the MDM10-containing ERMES in yeast is very different, both are organized around a β-barrel protein of the mitochondrial porin family that mediates a DNA–cytoskeleton linkage that is essential for mitochondrial DNA inheritance.Mitochondria are a hallmark of all eukaroytic cells. They derive from an endosymbiontic event between a free-living bacterium and a presumably prokaryotic host cell. More than 1.5 billion years of evolution resulted in a great diversification of mitochondria. As a consequence, the shape and number of organelles per cell as well as size, content, copy number, and organization of their genomes vary greatly between different taxons (1). However, all eukaryotes must be able to faithfully transmit mitochondria to their offspring (2, 3).Unlike most other eukaryotes, the parasitic protozoa Trypanosoma brucei has a single mitochondrion throughout its life and its cell cycle. Due to the single-unit nature of the mitochondrion, its duplication must be coordinated with the duplication of the nucleus (4). The mitochondrial genome of T. brucei, termed kinetoplast DNA (kDNA), is essential for growth of both the procyclic insect stage and the bloodstream form of the parasite (5). It consists of a disk-shaped single-unit kDNA network that localizes to a distinct region within the mitochondrial matrix (6). The kDNA is physically connected with the cytosolic basal body, the organizing center of the eukaryotic flagellum, via a high-order transmembrane structure termed tripartite attachment complex (TAC) (7) of which only few components have been identified (810). Replication of the kDNA network occurs at a defined stage of the cell cycle shortly before the onset of the nuclear S phase. After replication, the kDNA networks need to be correctly positioned so that during cell and mitochondrial division each daughter cell receives a single organelle with a single kDNA network. This process requires an intact TAC and is mediated by the movement of the basal body: one kDNA network remains connected to the basal body of the old flagellum whereas the other one segregates with the basal body of the new flagellum (7, 11).Unlike trypanosomes, Saccharomyces cerevisiae propagates by budding and contains highly dynamic mitochondria that constantly divide and fuse (12, 13). Mitochondrial inheritance in budding yeast therefore requires a mechanism to move mitochondria and their genomes from the mother cell into the growing bud. The protein-associated mitochondrial genomes of S. cerevisiae, termed nucleoids, localize to dozens of globular foci that are distributed all over the organelles. Most actively replicating nucleoids are associated with a protein complex that includes the outer membrane (OM) protein MDM10 as a central unit, as well as the proteins MDM12, MDM34, and MMM1 (1416). The protein complex forms the endoplasmic reticulum (ER)–mitochondria encounter structure (ERMES) tethering the ER to the mitochondrion (17). The ERMES has also been suggested to connect to cytosolic actin fibers that mediate the movement of mitochondria to the bud of dividing yeast cells (14, 18, 19). Besides its role in mitochondrial inheritance, the ERMES has been implicated in maintenance of mitochondrial morphology and in phospholipid and calcium exchange as well as in the assembly of the protein translocase of the mitochondrial OM (TOM) (20, 21). Some of the proposed ERMES functions are controversial and there is evidence that some of them might be due to secondary effects caused by the drastically altered mitochondrial morphology (22).The central ERMES subunit, the β-barrel protein MDM10 belongs to the mitochondrial porin superfamily, which comprises the three members voltage-dependent anion channel (VDAC), Tom40, and MDM10. Whereas VDAC and Tom40 have so far been found in all eukaryotes, including T. brucei (23, 24), MDM10 is specific to the fungal clade.In this study we identify a mitochondrial OM protein of T. brucei as a novel component of the TAC. We show that the protein defines a novel subclass of the mitochondrial porin superfamily that is specialized in mitochondrial DNA inheritance.  相似文献   
108.
The purpose of this study is to review the published literature for the range of radiographic findings present in patients suffering from coronavirus disease 2019 infection. This novel corona virus is currently the cause of a worldwide pandemic. Pulmonary symptoms and signs dominate the clinical picture and radiologists are called upon to evaluate chest radiographs (CXR) and computed tomography (CT) images to assess for infiltrates and to define their extent, distribution and progression. Multiple studies attempt to characterize the disease course by looking at the timing of imaging relative to the onset of symptoms. In general, plain CXR show bilateral disease with a tendency toward the lung periphery and have an appearance most consistent with viral pneumonia. Chest CT images are most notable for showing bilateral and peripheral ground glass and consolidated opacities and are marked by an absence of concomitant pulmonary nodules, cavitation, adenopathy and pleural effusions. Published literature mentioning organ systems aside from pulmonary manifestations are relatively less common, yet present and are addressed in this review. Similarly, publications focusing on imaging modalities aside from CXR and chest CT are sparse in this evolving crisis and are likewise addressed in this review. The role of imaging is examined as it is currently being debated in the medical community, which is not at all surprising considering the highly infectious nature of Severe Acute Respiratory Syndrome coronavirus 2.  相似文献   
109.

Background

GS-4774 is a recombinant, heat-killed, yeast-based immunotherapy engineered to express hepatitis B virus (HBV)-specific antigens. GS-4774 is being developed as a therapeutic vaccine for chronic HBV infection. The aim of this study was to assess the safety, tolerability and immunogenicity of GS-4774 in healthy subjects.

Design

This was a randomized, open-label, dose-ascending study. Subjects were allocated to one of three dose groups (n = 20 per group) to receive 10, 40 or 80 yeast units (YU; 1 YU = 107 yeast) of GS-4774 in two immunization regimens (five subcutaneous injections at weekly intervals with one monthly booster or three subcutaneous injections at monthly intervals). T-cell-mediated responses were determined by interferon (IFN)-γ enzyme-linked immunospot (ELISpot) assay and lymphocyte-proliferation assay (LPA).

Results

Adverse events were reported by 39 of 60 (65%) subjects; all were mild or moderate and none was serious. Adverse events occurred most frequently in the highest dose group, 80 YU, and the number of individual events was higher after weekly immunization than monthly. The most common adverse events were injection-site reactions. Most (88%) subjects responded to GS-4774 by at least one of the T-cell assays. Following immunization with GS-4774, IFN-γ-producing T-cells specific for HBV antigens were detectable in 30 (51%) subjects. The ELISpot response was observed at all doses, with the highest frequency of responders occurring at the highest dose (10 YU: 45%; 40 YU: 35%; 80 YU: 74%). Proliferative responses to HBV recombinant antigens were observed in 90% subjects; responses were mainly independent of GS-4774 dose and immunization regimen.

Conclusions

GS-4774 was safe and well-tolerated in healthy subjects with injection-site reactions being the most frequently reported adverse events. With both weekly and monthly regimens, GS-4774 provided HBV-specific immune responses at all doses evaluated. Further evaluation of GS-4774 is ongoing in patients with chronic HBV infection.Clinical trial registry: Clinicaltrials.gov (NCT01779505)  相似文献   
110.
Parent‐of‐origin–dependent (epi)genetic factors are important determinants of prenatal development that program adult phenotype. However, data on magnitude and specificity of maternal and paternal genome effects on fetal bone are lacking. We used an outbred bovine model to dissect and quantify effects of parental genomes, fetal sex, and nongenetic maternal effects on the fetal skeleton and analyzed phenotypic and molecular relationships between fetal muscle and bone. Analysis of 51 bone morphometric and weight parameters from 72 fetuses recovered at day 153 gestation (54% term) identified six principal components (PC1–6) that explained 80% of the variation in skeletal parameters. Parental genomes accounted for most of the variation in bone wet weight (PC1, 72.1%), limb ossification (PC2, 99.8%), flat bone size (PC4, 99.7%), and axial skeletal growth (PC5, 96.9%). Limb length showed lesser effects of parental genomes (PC3, 40.8%) and a significant nongenetic maternal effect (gestational weight gain, 29%). Fetal sex affected bone wet weight (PC1, p < 0.0001) and limb length (PC3, p < 0.05). Partitioning of variation explained by parental genomes revealed strong maternal genome effects on bone wet weight (74.1%, p < 0.0001) and axial skeletal growth (93.5%, p < 0.001), whereas paternal genome controlled limb ossification (95.1%, p < 0.0001). Histomorphometric data revealed strong maternal genome effects on growth plate height (98.6%, p < 0.0001) and trabecular thickness (85.5%, p < 0.0001) in distal femur. Parental genome effects on fetal bone were mirrored by maternal genome effects on fetal serum 25‐hydroxyvitamin D (96.9%, p < 0.001) and paternal genome effects on alkaline phosphatase (90.0%, p < 0.001) and their correlations with maternally controlled bone wet weight and paternally controlled limb ossification, respectively. Bone wet weight and flat bone size correlated positively with muscle weight (r = 0.84 and 0.77, p < 0.0001) and negatively with muscle H19 expression (r = –0.34 and –0.31, p < 0.01). Because imprinted maternally expressed H19 regulates growth factors by miRNA interference, this suggests muscle‐bone interaction via epigenetic factors. © 2014 American Society for Bone and Mineral Research.  相似文献   
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