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101.
Maria P. Lemos Javier R. Lama Shelly T. Karuna Youyi Fong Silvia M. Montano Carmela Ganoza Raphael Gottardo Jorge Sanchez M. Juliana McElrath 《PloS one》2014,9(9)
Male circumcision provides partial protection against multiple sexually transmitted infections (STIs), including HIV, but the mechanisms are not fully understood. To examine potential vulnerabilities in foreskin epithelial structure, we used Wilcoxon paired tests adjusted using the false discovery rate method to compare inner and outer foreskin samples from 20 healthy, sexually active Peruvian males who have sex with males or transgender females, ages 21–29, at elevated risk of HIV infection. No evidence of epithelial microtrauma was identified, as assessed by keratinocyte activation, fibronectin deposition, or parakeratosis. However, multiple suprabasal tight junction differences were identified: 1) inner foreskin stratum corneum was thinner than outer (p = 0.035); 2) claudin 1 had extended membrane-bound localization throughout inner epidermis stratum spinosum (p = 0.035); 3) membrane-bound claudin 4 was absent from inner foreskin stratum granulosum (p = 0.035); and 4) occludin had increased membrane deposition in inner foreskin stratum granulosum (p = 0.042) versus outer. Together, this suggests subclinical inflammation and paracellular transport modifications to the inner foreskin. A setting of inflammation was further supported by inner foreskin epithelial explant cultures secreting higher levels of GM-CSF (p = 0.029), IP-10 (p = 0.035) and RANTES (p = 0.022) than outer foreskin, and also containing an increased density of CCR5+ and CD4+ CCR5+ cells (p = 0.022). Inner foreskin dermis also secreted more RANTES than outer (p = 0.036), and had increased density of CCR5+ cells (p = 0.022). In conclusion, subclinical changes to the inner foreskin of sexually active males may support an inflammatory state, with availability of target cells for HIV infection and modifications to epidermal barriers, potentially explaining the benefits of circumcision for STI prevention. 相似文献
102.
Leukocyte-endothelial interactions are early and critical events in acute and chronic inflammation and can, when dysregulated, mediate tissue injury leading to permanent pathological damage. Existing conventional assays allow the analysis of leukocyte adhesion molecules only after the extraction of leukocytes from the blood. This requires the blood to undergo several steps before peripheral blood leukocytes (PBLs) can be ready for analysis, which in turn can stimulate PBLs influencing the research findings. The autoperfused micro flow chamber assay, however, allows scientists to study early leukocytes functional dysregulation using the systemic flow of a live mouse while having the freedom of manipulating a coated chamber. Through a disease model, the functional expression of leukocyte adhesion molecules can be assessed and quantified in a micro-glass chamber coated with immobilized endothelial adhesion molecules ex vivo. In this model, the blood flows between the right common carotid artery and left external jugular vein of a live mouse under anesthesia, allowing the interaction of native PBLs in the chamber. Real-time experimental analysis is achieved with the assistance of an intravital microscope as well as a Harvard Apparatus pressure device. The application of a flow regulator at the input point of the glass chamber allows comparable physiological flow conditions amongst the experiments. Leukocyte rolling velocity is the main outcome and is measured using the National Institutes of Health open-access software ImageJ. In summary, the autoperfused micro flow chamber assay provides an optimal physiological environment to study leukocytes endothelial interaction and allows researchers to draw accurate conclusions when studying inflammation. 相似文献
103.
Male courtship behavior in Drosophila melanogaster is controlled by two main regulators, fruitless (fru) and doublesex (dsx). Their sex-specific expression in brain neurons has been characterized in detail, but little is known about the downstream targets of the sex-specific FRU and DSX proteins and how they specify the function of these neurons. While sexual dimorphism in the number and connections of fru and dsx expressing neurons has been observed, a majority of the neurons that express the two regulators are present in both sexes. This poses the question which molecules define the sex-specific function of these neurons. Signaling molecules are likely to play a significant role. We have identified a predicted G-protein coupled receptor (GPCR), CG4395, that is required for male courtship behavior. The courtship defect in the mutants can be rescued by expression of the wildtype protein in fru neurons of adult males. The GPCR is expressed in a subset of fru-positive antennal glomeruli that have previously been shown to be essential for male courtship. Expression of 4395-RNAi in GH146 projection neurons lowers courtship. This suggests that signaling through the CG4395 GPCR in this subset of fru neurons is critical for male courtship behavior. 相似文献
104.
Introduction
In 2010, the Global Fund provided more than 75% of external international financing for malaria control. The Global Fund uses performance based funding in the grants it finances. This paper analyses the indicators used to measure the performance of Global Fund supported malaria grants in Asia.Methods
Indicators used in the performance frameworks for all Global Fund supported malaria grants in Asia were retrieved from grant database and grouped into impact, outcome, output and input categories and categorized by service delivery areas. Indicators of each group were compared over rounds. Indicators used in performance frameworks were compared with internationally adopted indicators included in the Monitoring and Evaluation Toolkit developed by the Global Fund and international technical agencies.Results
Between 2002 and 2010, 1,434 indicators were included in the performance frameworks of the 48 malaria grants awarded in Asia, including 229 impact and 227 outcome indicators, 437 output and 541 input indicators, with an average of 29.9 indicators per grant. The proportion of impact and outcome indicators increased over rounds, with that of input indicators declining from 44.1% in Round 1 to 22.7% in Round 9.Conclusions
Input indicators, which have predominated the performance frameworks of the Global Fund supported malaria programs in Asia have declined between Rounds 1 and 9. However, increased alignment with internationally adopted indicators included in the Monitoring and Evaluation Toolkit is needed to improve the validity of reported results. 相似文献105.
We screened 44 heterologous microsatellites isolated in species of the families Threskiornithidae, Ciconiidae and Ardeidae for their use in a migratory waterbird, the white-faced ibis Plegadis chihi (Vieillot, 1817) (Threskiornithidae). Of the screened loci, 57% amplified successfully and 24% were polymorphic. In two breeding colonies from southern Brazil (N = 131) we detected 32 alleles (2-10 alleles/locus). Average He over all loci and colonies was 0.55, and the combined probability of excluding false parents, 98%. There was no departure from HWE in any loci or population. Eru6 and Eru4 loci were in non-random association in the Alvorada colony, and NnNF5 and Eru5 in both populations. AMOVA analysis indicated that most of the genetic diversity was contained within populations. Structure analysis suggested a single population, and F(ST) value showed weak genetic structuring (F(ST) = 0.009, p = 0.05). The two populations are apparently connected through gene-flow. The panel of six microsatellites optimized here was sufficiently informative for characterizing the genetic diversity and structure in these natural populations of the white-faced ibis. The information generated could be useful in future studies of genetic diversity, relatedness and the mating system in Plegadis chihi and related species. 相似文献
106.
The potency of a series of sulfonamide tubulin inhibitors against the growth of Trypanosoma brucei (T. brucei), as well as human cancer and primary fibroblast cells were evaluated with the aim of determining whether compounds that selectively inhibit parasite proliferation could be identified. Several compounds showed excellent selectivity against T. brucei growth, and have the potential to be used for the treatment of Human African trypanosomiasis. A T. brucei tubulin protein homology model was built based on the crystal structure of the bovine tubulin. The colchicine-binding domain, which is also the binding site of the tested sulfonamide tubulin inhibitors, showed clear differences between the tubulin structures and presumably explained the selectivity of the compounds. 相似文献
107.
Summary A rapid procedure for plating the thermo-acidophilic archaebacterium Sulfolobus solfataricus using Gerlite as a gelling agent is reported. The technique uses a clear, single layer in which the colonies are grown. 相似文献
108.
B. Nicolaus F. Marsiglia E. Esposito L. Lama A. Trincone G. di Prisco A. Gambacorta M.J. Valderrama W.D. Grant 《FEMS microbiology letters》1992,99(2-3):145-149
Abstract Five non-motile Gram-positive cocci were isolated from saline located in geothermal regions of the Antarctic continent. The organisms were extremely halotolerant growing between 0 and 4.2 M NaCl. On the basis of the results of phenotypic characterizations, lipid and quinone analyses, and the amino acid composition of the cell the isolates have been assigned to the genus Micrococcus . 相似文献
109.
Alessandra M. Tomasulo‐Seccomandi Nancy A. Schable A. Lawrence Bryan I. Lehr Brisbin Silvia N. Del Lama Travis C. Glenn 《Molecular ecology resources》2003,3(4):563-566
We isolated 11 polymorphic microsatellite loci for wood stork (Mycteria americana). Polymerase chain reaction (PCR) primers and conditions are described for the amplification of five dinucleotide, one trinucleotide and five tetranucleotide microsatellite loci. The PCR primers were tested on two wood stork populations, Fazenda Ipiranga, Mato Grosso, Brazil (n = 11) and Tamiami West, Everglades, Florida, USA (n = 20). The primers yielded two to four alleles per locus, an observed heterozygosity of 0.0–0.727 and a polymorphic information content of 0.048–0.604. The low level of polymorphism for these markers is consistent with previous studies of this species. 相似文献
110.
A halophilic thermotolerant Bacillus isolated from a marine hot spring able to produce a new exopolysaccharide 总被引:1,自引:0,他引:1
Teresa L. Maugeri Concetta Gugliandolo Daniela Caccamo Adriana Panico Licia Lama Agata Gambacorta Barbara Nicolaus 《Biotechnology letters》2002,24(7):515-519
A halophilic, thermotolerant Bacillus strain (B3-15), isolated from water of a shallow, marine hot spring at Vulcano Island (Eolian Islands, Italy), produced an exocellular polysaccharide at 165 mg l–1. It grew on kerosene as sole carbon source and was resistant to Cd2+, Zn2+, As2+ and Hg2+. From 16S rDNA analysis, strain B3-15 was related to B. licheniformis. The exopolysaccharide was a tetrasaccharide repeating unit essentially constituted by sugars having a manno-pyranosidic configuration. 相似文献