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Despite aggressive research, central nervous system (CNS) disorders, including blood-brain barrier (BBB) injury caused by microbial infection, stroke, abused drugs [e.g., methamphetamine (METH) and nicotine], and other pathogenic insults, remain the world''s leading cause of disabilities. In our previous work, we found that dysfunction of brain microvascular endothelial cells (BMECs), which are a major component of the BBB, could be caused by nicotine, meningitic pathogens and microbial factors, including HIV-1 virulence factors gp41 and gp120. One of the most challenging issues in this area is that there are no available cell-based biomarkers in peripheral blood for BBB disorders caused by microbial and non-microbial insults. To identify such cellular biomarkers for BBB injuries, our studies have shown that mice treated with nicotine, METH and gp120 resulted in increased blood levels of CD146+(endothelial marker)/S100B+ (brain marker) circulating BMECs (cBMECs) and CD133+[progenitor cell (PC) marker]/CD146+ endothelial PCs (EPCs), along with enhanced Evans blue and albumin extravasation into the brain. Nicotine and gp120 were able to significantly increase the serum levels of ubiquitin C-terminal hydrolase 1 (UCHL1) (a new BBB marker) as well as S100B in mice, which are correlated with the changes in cBMECs and EPCs. Nicotine- and meningitic E. coli K1-induced enhancement of cBMEC levels, leukocyte migration across the BBB and albumin extravasation into the brain were significantly reduced in alpha7 nAChR knockout mice, suggesting that this inflammatory regulator plays an important role in CNS inflammation and BBB disorders caused by microbial and non-microbial factors. These results demonstrated that cBMECs as well as EPCs may be used as potential cell-based biomarkers for indexing of BBB injury. 相似文献
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International Journal of Peptide Research and Therapeutics - Additional biological protection; blood brain barrier (BBB) to neuronal tissue is essential against invading infections and unwanted... 相似文献
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Birk Poller Jürgen Drewe Stephan Krähenbühl Jörg Huwyler Heike Gutmann 《Cellular and molecular neurobiology》2010,30(1):63-70
Brain capillary endothelial cells form the blood–brain barrier (BBB), a highly selective permeability membrane between the
blood and the brain. Besides tight junctions that prevent small hydrophilic compounds from passive diffusion into the brain
tissue, the endothelial cells express different families of drug efflux transport proteins that limit the amount of substances
penetrating the brain. Two prominent efflux transporters are the breast cancer resistance protein and P-glycoprotein (P-gp).
During inflammatory reactions, which can be associated with an altered BBB, pro-inflammatory cytokines are present in the
systemic circulation. We, therefore, investigated the effect of the pro-inflammatory cytokines interleukin-1β (IL-1β), interleukin-6
(IL-6) and tumor necrosis factor-α (TNF-α) on the expression and activity of BCRP and P-gp in the human hCMEC/D3 cell line.
BCRP mRNA levels were significantly reduced by IL-1β, IL-6 and TNF-α. The strongest BCRP suppression at the protein level
was observed after IL-1β treatment. IL-1β, IL-6 and TNF-α also significantly reduced the BCRP activity as assessed by mitoxantrone
uptake experiments. P-gp mRNA levels were slightly reduced by IL-6, but significantly increased after TNF-α treatment. TNF-α
also increased protein expression of P-gp but the uptake of the P-gp substrate rhodamine 123 was not affected by any of the
cytokines. This in vitro study indicates that expression levels and activity of BCRP, and P-gp at the BBB may be altered by
acute inflammation, possibly affecting the penetration of their substrates into the brain. 相似文献
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Pseudorasbora parva (Pisces, Cyprinidae) is an invasive species from eastern Asia. Known in France since 1983, it has only been observed since 1993 in the Rh?ne delta where large populations occur. 203 specimens of that fish species have been examined for L3-larvae of Anguillicola crassus. 35% of the fish were found to be infected. 相似文献
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Ulrich Marcus Ford Hickson Peter Weatherburn Martina Furegato Michele Breveglieri Rigmor C. Berg Axel J. Schmidt for the EMIS network 《PloS one》2015,10(3)
Background
The preventive effects of antiretroviral treatment (ART) on onward transmission of HIV are a major reason for broadening eligibility for ART. In the WHO European Region, surveillance reveals substantial differences in access to ART across regions and sub-populations. We analysed self-reported data on ART and reasons for not taking ART from EMIS, a large Pan-European Internet survey among men-who-have-sex-with-men (MSM).Methods
Respondents from 38 European countries reported their last HIV test result and, if diagnosed with HIV, their treatment status, and reasons for not taking or having stopped ART from a 7 item multiple choice list and/ or answered an open-ended question to give other reasons. Responses were classified as fear of consequences, perceived lack of need, and ART inaccessibility based on factor analysis. Associations between not taking ART because of fear of consequences, and demographic, behavioural and contextual indicators were identified in a multivariable regression model.Results
13,353 (7.7%) of 174,209 respondents had been diagnosed with HIV. Among them 3,391 (25.4%) had never received ART, and 278 (2.1%) had stopped taking ART. Perceived lack of need was by far the most common reason for not taking or stopping ART (mentioned by 3259 (88.8%) respondents), followed by fear of consequences (428 (11.7%)), and ART inaccessibility (86 (2.3%)). For all reasons, an East-West gradient could be seen, with larger proportions of men living in Central and Eastern Europe reporting reasons other than medical advice for not taking ART. A minority of men were reluctant to start ART independent of medical advice and this was associated with experiences of discrimination in health care systems.Conclusions
ART is widely available for MSM diagnosed with HIV across Europe. Not being on treatment is predominantly due to treatment not being recommended by their physician and/or not perceived to be needed by the respondent. 相似文献8.
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In order to reveal the structure of the sparsely known deeper sublittoral hard bottom communities of glacial Kongsfjorden, the macroepibenthos from six depth zones (30–200?m) was analysed. A total of 180 still images derived from 6-h video recorded at the Kongsfjordneset remotely operated vehicle station were assessed quantitatively. Overall 27 mainly suspension-feeding species/taxa were observed. Of these, two-thirds have an arcto-boreal distribution, while the remainder are cosmopolitan. The overall mean epibenthos abundance was 33 ind. m?2 with maximum values at 150?m depth (97.9 ind. m?2). The majority of the taxa inhabited the entire depth range. Encrusting red algae, an unidentified sponge and the sea anemone Urticina eques, characterized the assemblage of the shallow zone. The sea anemones Hormathia spp. were important below 30?m, the Serpulid polychaete Protula tubularia was characteristic for the community below 50?m and the demosponge Haliclona sp. was a key taxon between 100 and 200?m depth. Cluster analysis and non-metrical multidimensional scaling based on abundance data showed differences between the assemblages along the bathymetric gradient, but only in the shallower depths in relation to the substratum surface incline. As surface and tidal current impacts attenuate with increasing depth, there is a gradual trend from robust key species towards more fragile ones (i.e. P. tubularia), in line with the ‘Physical control hypothesis’. 相似文献
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Patrick Nadol Siobhan O’connor Hao Duong Linh-Vi N. Le Pham Hong Thang Tran Hong Tram Hoang Thi Thanh Ha Michelle S. Mcconnell Jeff Partridge John Kaldor Matthew Law Tuan Anh Nguyen 《PloS one》2015,10(2)
IntroductionGiven the overlapping modes of transmission of HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV), understanding the burden and relationship of these infections is critical for an effective response. Representative data on these infections among males who inject drugs (MWID), the key high-risk population for HIV in Vietnam, are currently lacking.MethodsData and stored specimens from Vietnam’s 2009-2010 Integrated Biologic and Behavioral Survey, a cross-sectional study among high-risk populations, were used for this analysis. Plasma samples were tested for HIV, HBV, and HCV using commercial assays. A questionnaire was administered to provide demographic, behavior, and service-uptake information. Provincial-level analyses were conducted to profile MWID enrollees and to provide estimates on the prevalence of HIV, HBV, and HCV infection.ResultsAmong 3010 MWID sampled across 10 provinces, the median (range) HIV prevalence was 28.1% (1.0%-55.5%). Median prevalence for current HBV infection (HBsAg+) was 14.1% (11.7%-28.0%), for previous exposure to HBV (total anti-HBc+) was 71.4% (49.9%-83.1%), and for current or past HCV infection (HCV Ag/Ab+) was 53.8% (10.9%-80.8%). In adjusted analysis, HBsAg+ (aOR: 2.09, 1.01-4.34) and HCV Ag/Ab+ (aOR: 19.58, 13.07-29.33) status were significantly associated with HIV infection; the association with total anti-HBc+ approached significance (aOR: 1.29, 0.99-1.68).ConclusionThe prevalence and association between HIV, HBV, and HCV are high among MWID in Vietnam. These findings indicate the need for integrated policies and practice that for the surveillance, prevention, screening, and treatment of both HIV and viral hepatitis among MWID in Vietnam. 相似文献
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Guillermo A. Logarzo Eduardo G. Virla Erica Luft Albarracin Serguei V. Triapitsyn Walker A. Jones Jesse H. de León Juan A. Briano 《BioControl》2012,57(1):37-48
The South American egg parasitoid Gonatocerus sp. near tuberculifemur “Clade 1” (G. sp. “Clade 1”) (Hymenoptera: Mymaridae) is a new association of the glassy-winged sharpshooter (GWSS), Homalodisca
vitripennis (Germar) (Cicadellidae) and a candidate for its biological control in California, USA. In Argentina, G. sp. “Clade 1” was screened in the laboratory (no-choice tests) and in the field (multiple choice tests) against eggs of 32
Auchenorrhyncha host species and other four potential hosts unrelated to sharpshooters. In no-choice assays, it parasitized
only eggs within the leafhopper tribe Proconiini. In contrast, in the long term field tests, it emerged not only from eggs
of the Proconiini but also from two species of Cicadellini at low numbers (five wasps out of 698 exposed eggs). Two interpretations
arise from the results: (1) Host associations of G. sp. “Clade 1” are restricted to the Proconiini whereas field parasitization of the Cicadellini species were false positive,
or (2) G. sp. “Clade 1” parasitizes also some Cicadellini species and its rejection in the laboratory was a false negative. Both interpretations
are discussed. Insect motivation could be the explanation for the negative results in the no-choice tests. On the other hand,
in the more natural field situations, the host selection process and oviposition behavior should not have been affected and
host range would be more realistic. The parasitism of the Cicadellini species would be indicative of a potential non-target
effect on the sharpshooters in the USA. 相似文献
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《Bulletin of mathematical biology》1987,49(6):768-769
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Claudius F. Kratochwil Maggie M. Sefton Yipeng Liang Axel Meyer 《BMC developmental biology》2017,17(1):15