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991.
992.
Toberer F Sykora J Göttel D Ruland V Hartschuh W Enk A Luger TA Beissert S Loser K Joos S Krammer PH Kuhn A 《Experimental dermatology》2011,20(7):600-602
Recently, it was discovered that the receptor activator of nuclear factor κB (RANK)/RANK ligand (RANKL) is part of an important signal transduction pathway for tissue homoeostasis. Therefore, we were interested in investigating RANKL expression in the epidermis of skin lesions from patients with different subtypes of cutaneous lupus erythematosus (CLE) and psoriasis as well as normal healthy donors. Using the tissue microarray technique, skin biopsy specimens were evaluated by immunohistochemistry. RANKL showed a significantly increased expression in the epidermis of skin biopsy specimens from patients with psoriasis (median: 4, range: 0-5) compared to patients with CLE (median: 0, range: 0-4) (P<0.001). No significant differences in epidermal RANKL expression between the CLE subtypes were detected. These data show a different expression of RANKL in the epidermis of skin lesions from patients with CLE compared to those with psoriasis suggesting that RANKL might play an important role in the pathogenesis of the disease. 相似文献
993.
994.
Kupka R Mugusi F Aboud S Msamanga GI Finkelstein JL Spiegelman D Fawzi WW 《The American journal of clinical nutrition》2008,87(6):1802-1808
BACKGROUND: In observational studies, adequate selenium status has been associated with better pregnancy outcomes and slowed HIV disease progression. OBJECTIVE: We investigated the effects of daily selenium supplements on CD4 cell counts, viral load, pregnancy outcomes, and maternal and infant mortality among 913 HIV-infected pregnant women. DESIGN: In this randomized, double-blind, placebo-controlled trial, eligible women between 12 and 27 wk of gestation were given daily selenium (200 mug as selenomethionine) or placebo as supplements from recruitment until 6 mo after delivery. All women received prenatal iron, folic acid, and multivitamin supplements irrespective of experimental assignment. RESULTS: The selenium regimen had no significant effect on maternal CD4 cell counts or viral load. Selenium was marginally associated with a reduced risk of low birth weight [relative risk (RR) = 0.71; 95% CI: 0.49, 1.05; P = 0.09] and increased risk of fetal death (RR = 1.58; 95% CI = 0.95, 2.63; P = 0.08), but had no effect on risk of prematurity or small-for-gestational age birth. The regimen had no significant effect on maternal mortality (RR = 1.02; 95% CI = 0.51, 2.04; P = 0.96). There was no significant effect on neonatal or overall child mortality, but selenium reduced the risk of child mortality after 6 wk (RR = 0.43; 95% CI = 0.19, 0.99; P = 0.048). CONCLUSION: Among HIV-infected women from Dar es Salaam, Tanzania, selenium supplements given during and after pregnancy did not improve HIV disease progression or pregnancy outcomes, but may improve child survival. This trial was registered at clinicaltrials.gov as NCT00197561. 相似文献
995.
Expression of Human Neutrophil Peptides (HNP) 1-3 was recently found to be associated with development of colorectal cancer. Raised defensin-expression in tumours is believed to stem from increased infiltration of neutrophils into tumour environment. To further specify the role of alpha-defensins in tumourigenesis and progression, HNP1-3 were analyzed in colorectal adenomas and carcinomas of 87 patients and quantified in relation to cancer stage and grading. Using the ProteinChip arrays, HNP1-3 were found upregulated in both colorectal adenomas and carcinomas. By combining the array with Laser capture microscopy we were able to confirm that HNP1-3 are expressed by tumour cells but not by neutrophils or other tumour invading cells. These findings suggest that alpha-defensins are more likely to contribute to tumour growth than they are to mount an effective host anti-tumour response. However, the amount of HNP-expression was not found to be related to tumour stage, grading, and serological tumour markers. 相似文献
996.
997.
Graham SP Pellé R Yamage M Mwangi DM Honda Y Mwakubambanya RS de Villiers EP Abuya E Awino E Gachanja J Mbwika F Muthiani AM Muriuki C Nyanjui JK Onono FO Osaso J Riitho V Saya RM Ellis SA McKeever DJ MacHugh ND Gilbert SC Audonnet JC Morrison WI van der Bruggen P Taracha EL 《Infection and immunity》2008,76(2):685-694
Immunity against the bovine intracellular protozoan parasite Theileria parva has been shown to be mediated by CD8 T cells. Six antigens targeted by CD8 T cells from T. parva-immune cattle of different major histocompatibility complex (MHC) genotypes have been identified, raising the prospect of developing a subunit vaccine. To facilitate further dissection of the specificity of protective CD8 T-cell responses and to assist in the assessment of responses to vaccination, we set out to identify the epitopes recognized in these T. parva antigens and their MHC restriction elements. Nine epitopes in six T. parva antigens, together with their respective MHC restriction elements, were successfully identified. Five of the cytotoxic-T-lymphocyte epitopes were found to be restricted by products of previously described alleles, and four were restricted by four novel restriction elements. Analyses of CD8 T-cell responses to five of the epitopes in groups of cattle carrying the defined restriction elements and immunized with live parasites demonstrated that, with one exception, the epitopes were consistently recognized by animals of the respective genotypes. The analysis of responses was extended to animals immunized with multiple antigens delivered in separate vaccine constructs. Specific CD8 T-cell responses were detected in 19 of 24 immunized cattle. All responder cattle mounted responses specific for antigens for which they carried an identified restriction element. By contrast, only 8 of 19 responder cattle displayed a response to antigens for which they did not carry an identified restriction element. These data demonstrate that the identified antigens are inherently dominant in animals with the corresponding MHC genotypes. 相似文献
998.
999.
Presence of HER4 associates with increased sensitivity to Herceptin™ in patients with metastatic breast cancer
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Andrea Sassen Simone Diermeier-Daucher Manuela Sieben Olaf Ortmann Ferdinand Hofstaedter Stephan Schwarz Gero Brockhoff 《Breast cancer research : BCR》2009,11(4):R50-10
Introduction
HER2 overexpression, or rather HER2 gene amplification, is indicative for Herceptin therapy in both metastatic and pre-metastatic breast cancer patients. Patient's individual sensitivity to Herceptin treatment, however, varies enormously and spans from effectual responsiveness over acquired insensitivity to complete resistance from the outset. Thus no predictive information can be deduced from HER2 determination so that molecular biomarkers indicative for Herceptin sensitivity or resistance need to be identified. Both ErbB receptor-dependent signalling molecules as well as HER2-related ErbB receptor tyrosine kinases, known to mutually interact and to cross-regulate each other are prime candidates to be involved in cellular susceptibility to Herceptin. 相似文献1000.
Florian Sommer Ferdinand Brandl Barbara Weiser Jörg Teßmar Torsten Blunk Achim Göpferich 《Experimental eye research》2009,88(5):995-999
Hyalocytes, the cells of the vitreous body, are assumed to be involved in physiological as well as patho-physiological processes within the eye. However, current knowledge about the cells is still limited. As different morphological types of hyalocytes are described in the literature, it seems reasonable to try to isolate individual populations prior to characterization of single cell types. To achieve this, the present study investigated the utility of fluorescence activated cell sorting (FACS) for hyalocyte separation.Subsequent to digestion of vitreous bodies using collagenase, the resulting cell suspension was analyzed and separated using FACS without any additional staining. Two-parameter dot plots of forward scatter (indicating size) against sideward scatter (indicating granularity) showed two distinct cell populations; staining with propidium iodide confirmed that both populations represent living cells. After sorting, cells of both populations were seeded on tissue culture plastic (tissue culture treated polystyrene). Only one population attached and proliferated, whereas the other population was non-adherent. Even when seeding the native cell mix, only one population of cells was observed after two passages, as indicated by FACS. Furthermore, ascorbic acid increased proliferation of these cells similarly to the proliferation of the separated cell population. These data point out that only one of the two populations adheres and proliferates on tissue culture plastic.To conclude, the established isolation technique allows for separation of clearly defined hyalocyte populations. Moreover, clear hints were obtained that only one of the two populations adheres and proliferates under the commonly applied culture conditions. 相似文献