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排序方式: 共有252条查询结果,搜索用时 15 毫秒
61.
62.
Bhogal RH Hodson J Bartlett DC Weston CJ Curbishley SM Haughton E Williams KT Reynolds GM Newsome PN Adams DH Afford SC 《PloS one》2011,6(3):e18222
Successful and consistent isolation of primary human hepatocytes remains a challenge for both cell-based therapeutics/transplantation and laboratory research. Several centres around the world have extensive experience in the isolation of human hepatocytes from non-diseased livers obtained from donor liver surplus to surgical requirement or at hepatic resection for tumours. These livers are an important but limited source of cells for therapy or research. The capacity to isolate cells from diseased liver tissue removed at transplantation would substantially increase availability of cells for research. However no studies comparing the outcome of human hepatocytes isolation from diseased and non-diseased livers presently exist. Here we report our experience isolating human hepatocytes from organ donors, non-diseased resected liver and cirrhotic tissue. We report the cell yields and functional qualities of cells isolated from the different types of liver and demonstrate that a single rigorous protocol allows the routine harvest of good quality primary hepatocytes from the most commonly accessible human liver tissue samples. 相似文献
63.
Christopher Steven Eickhoff Brian Anthony Dunn Nicole Lea Sullivan Daniel Fredric Hoft 《Memórias do Instituto Oswaldo Cruz》2013,108(4):508-511
Trypanosoma cruzi infects humans when infected triatomine
vector excreta contaminate breaks in skin or mucosal surfaces. T.
cruzi insect-derived metacyclic trypomastigotes (IMT) invade
through gastric mucosa after oral challenges without any visible inflammatory
changes, while cutaneous and conjunctival infections result in obvious local
physical signs. In this study we compared the infectivity of T.
cruzi IMT in mice after cutaneous and oral contaminative challenges
simulating natural infections. The 50% infective dose (ID50) for oral challenge
was 100 fold lower than the ID50for cutaneous challenge, indicating that oral
mucosal transmission is more efficient than cutaneous transmission. 相似文献
64.
65.
Stefano Tiziani Yunyi Kang Ricky Harjanto Joshua Axelrod Carlo Piermarocchi William Roberts Giovanni Paternostro 《PloS one》2013,8(12)
The tumor microenvironment is emerging as an important therapeutic target. Most studies, however, are focused on the protein components, and relatively little is known of how the microenvironmental metabolome might influence tumor survival. In this study, we examined the metabolic profiles of paired bone marrow (BM) and peripheral blood (PB) samples from 10 children with acute lymphoblastic leukemia (ALL). BM and PB samples from the same patient were collected at the time of diagnosis and after 29 days of induction therapy, at which point all patients were in remission. We employed two analytical platforms, high-resolution magnetic resonance spectroscopy and gas chromatography-mass spectrometry, to identify and quantify 102 metabolites in the BM and PB. Standard ALL therapy, which includes l-asparaginase, completely removed circulating asparagine, but not glutamine. Statistical analyses of metabolite correlations and network reconstructions showed that the untreated BM microenvironment was characterized by a significant network-level signature: a cluster of highly correlated lipids and metabolites involved in lipid metabolism (p<0.006). In contrast, the strongest correlations in the BM upon remission were observed among amino acid metabolites and derivatives (p<9.2×10-10). This study provides evidence that metabolic characterization of the cancer niche could generate new hypotheses for the development of cancer therapies. 相似文献
66.
Mariah Hassert Kyle J. Wolf Ahmad Rajeh Courtney Schiebout Stella G. Hoft Tae-Hyuk Ahn Richard J. DiPaolo James D. Brien Amelia K. Pinto 《PLoS neglected tropical diseases》2020,14(12)
Zika virus (ZIKV) is a significant global health threat due to its potential for rapid emergence and association with severe congenital malformations during infection in pregnancy. Despite the urgent need, accurate diagnosis of ZIKV infection is still a major hurdle that must be overcome. Contributing to the inaccuracy of most serologically-based diagnostic assays for ZIKV, is the substantial geographic and antigenic overlap with other flaviviruses, including the four serotypes of dengue virus (DENV). Within this study, we have utilized a novel T cell receptor (TCR) sequencing platform to distinguish between ZIKV and DENV infections. Using high-throughput TCR sequencing of lymphocytes isolated from DENV and ZIKV infected mice, we were able to develop an algorithm which could identify virus-associated TCR sequences uniquely associated with either a prior ZIKV or DENV infection in mice. Using this algorithm, we were then able to separate mice that had been exposed to ZIKV or DENV infection with 97% accuracy. Overall this study serves as a proof-of-principle that T cell receptor sequencing can be used as a diagnostic tool capable of distinguishing between closely related viruses. Our results demonstrate the potential for this innovative platform to be used to accurately diagnose Zika virus infection and potentially the next emerging pathogen(s). 相似文献
67.
Three new species of Ceratomyxa Thélohan, 1892 are described from the gall-bladders of two species of carcharhinid sharks collected off Heron and Lizard
Islands on the Great Barrier Reef, Australia. Ceratomyxa
carcharhini n. sp. and C.
melanopteri n. sp. are described from Carcharhinus melanopterus (Quoy & Gaimard), and Ceratomyxa
negaprioni n. sp. is described from Negaprion acutidens (Rüppell). These species are the first ceratomyxids reported from Australian elasmobranchs, and this is the first paper to
formally characterise a novel Ceratomyxa species from an elasmobranch using both morphology and small subunit ribosomal DNA sequence data. Maximum parsimony and Bayesian
inference analyses of the SSU rDNA dataset revealed that ceratomyxids from elasmobranchs form a sister clade to that of species
infecting marine teleosts and Palliatus indecorus Schulman, Kovaleva & Dubina, 1979. Furthermore, the only sequenced freshwater ceratomyxid, Ceratomyxa shasta Noble, 1950, fell outside the overall marine ceratomyxid clade. These data show that Ceratomyxa, as currently recognised, is polyphyletic and ignites discussion on whether Ceratomyxa should be split. However, further taxon sampling, particularly in freshwater systems, is required to establish relevant biological
divisions within the genus. 相似文献
68.
Sullivan NL Eickhoff CS Zhang X Giddings OK Lane TE Hoft DF 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(3):1358-1368
Trypanosoma cruzi is an intracellular parasite and the causative agent of Chagas disease. Previous work has shown that the chemokine receptor CCR5 plays a role in systemic T. cruzi protection. We evaluated the importance of CCR5 and CCL5 for mucosal protection against natural oral and conjunctival T. cruzi challenges. T. cruzi-immune CCR5(-/-) and wild-type C57BL/6 mice were generated by repeated infectious challenges with T. cruzi. CCR5(-/-) and wild-type mice developed equivalent levels of cellular, humoral, and protective mucosal responses. However, CCR5(-/-)-immune mice produced increased levels of CCL5 in protected gastric tissues, suggesting compensatory signaling through additional receptors. Neutralization of CCL5 in CCR5(-/-)-immune mice resulted in decreased mucosal inflammatory responses, reduced T. cruzi-specific Ab-secreting cells, and significantly less mucosal T. cruzi protection, confirming an important role for CCL5 in optimal immune control of T. cruzi replication at the point of initial mucosal invasion. To investigate further the mechanism responsible for mucosal protection mediated by CCL5-CCR5 signaling, we evaluated the effects of CCL5 on B cells. CCL5 enhanced proliferation and IgM secretion in highly purified B cells triggered by suboptimal doses of LPS. In addition, neutralization of endogenous CCL5 inhibited B cell proliferation and IgM secretion during stimulation of highly purified B cells, indicating that B cell production of CCL5 has important autocrine effects. These findings demonstrate direct effects of CCL5 on B cells, with significant implications for the development of mucosal adjuvants, and further suggest that CCL5 may be important as a general B cell coactivator. 相似文献
69.
We demonstrated that ginsenoside-Re (Re), a pharmacological active component of ginseng, is a functional ligand of glucocorticoid receptor (GR) using competitive ligand-binding assay (IC50 = 156.6 nM; Kd = 49.7 nM) and reporter gene assay. Treatment with Re (1 μM) raises intracellular Ca2+ ([Ca2+]i) and nitric oxide (NO) levels in human umbilical vein endothelial cells as measured using fura-2 and 4-amino-5-methylamino-2′,7′-difluorofluorescein diacetate, respectively. Western blot analysis shows that Re increased phosphorylation of endothelial nitric oxide synthase. These effects were abolished by GR antagonist RU486, siRNA targeting GR, non-selective cation channel blocker 2-aminoethyldiphenylborate, or in the absence of extracellular Ca2+, indicating Re is indeed an agonistic ligand for the GR and the activated GR induces rapid Ca2+ influx and NO production in endothelial cells. 相似文献
70.
Targeting base excision repair to improve cancer therapies 总被引:2,自引:0,他引:2
Most commonly used cancer therapies, particularly ionizing radiation and certain classes of cytotoxic chemotherapies, cause cell death by damaging DNA. Base excision repair (BER) is the major system responsible for the removal of corrupt DNA bases and repair of DNA single strand breaks generated spontaneously and induced by exogenous DNA damaging factors such as certain cancer therapies. In this review, the physico-chemical properties of the proteins involved in BER are discussed with particular emphasis on molecular mechanisms coordinating repair processes. The aim of this review is to apply extensive knowledge that currently exists regarding the biochemical mechanisms involved in human BER to the molecular biology of current therapies for cancer. It is anticipated that the application of this knowledge will translate into the development of novel effective therapies for improving existing treatments such as radiation therapy and oxaliplatin chemotherapy. 相似文献