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41.
42.
Dysregulation of proinflammatory and regulatory cytokines in HIV infected persons with active tuberculosis 总被引:2,自引:0,他引:2
Proinflammatory and regulatory cytokines have been implicated to play important role in immunopathology of HIV and tuberculosis (TB) infection. Capacity of unstimulated and mitogen-stimulated peripheral blood mononuclear cells (PBMCs) to secrete cytokines (interleukin (IL)-2, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), IL-4, IL-10 and IL-6) was estimated for 15 HIV-TB coinfected patients, 22 HIV seropositives without TB, 32 HIV negative TB patients, and 36 healthy subjects. Dually infected patients had suppression of both Th1 and Th2 cytokine secretion as evidenced by significantly lower production of IL-2, IFN-gamma and TNF-alpha as well as IL-4 and IL-10. Production of IL-2 and TNF-alpha was significantly decreased only in case of HIV infection. Significantly higher IL-6 secretion was found in unstimulated cultures in dually infected patients. The mitogen induced cytokine secretion was generally lower in HIV-TB coinfected patients indicating profound perturbation of both Th1 and Th2 responses. 相似文献
43.
Johnson JC Nettikadan SR Vengasandra SG Lovan S Muys J Henderson E Christiansen J 《In vitro cellular & developmental biology. Animal》2005,41(7):225-231
Summary Melanomacrophages (MMs) are a component of an internal, pigmented cell system in liver and splenic tissues of some fishes,
anurans, and reptiles. The cells have been found in centers or aggregates in sinusoids and are associated with cells capable
of producing a peptide cytokine and immunoglobulins. A unique cell extension process has been observed in turtle MMs placed
into cell culture, and this process has been studied by light and atomic force microscopy. These structures, referred to as
cablepodia, are uniquely straight, narrow, and unbranching and appear to originate from growth cones opposite lamellipodia.
Cablepodia were found to connect with other turtle MMs and fibroblasts forming cell networks. Dividing fibroblasts to which
a cablepodium attached ceased cell division. The observations collectively suggest that a principal reason for aggregations
of MMs in internal organs of lower vertebrates in their ability to form interconnected networks of cell processes for trapping
and processing of particulate matter, cells and infectious organisms and, possibly, for the communication of cell signals
and transfer of intracellular materials. 相似文献
44.
Iopamidol, a water-soluble contrast agent, has been rarely associated with seizures. We describe a case of generalized tonic-clonic seizure after cervical myelography with iopamidol in a previously healthy young man. In patients presenting with seizures, a history of recent myelography should be considered as an etiology. Iopamidol myelography may be associated with a risk of seizures. Clinicians need to be aware of this complication and inform their patients about such risk. 相似文献
45.
46.
Venkatesan Ramakrishnan Xavier Alexander Marialouis Jagadesan Sankarasubramanian Amutha Santhanam Anand Setty Balakrishnan 《Bioinformation》2021,17(1):126
The emerging NDM-producing Enterobactereciae is a major threat to public health. The association of NDM-7 with sequence type 101 E.coli is identified in very few numbers. Therefore, it is of interest to analyse the whole genome sequence of NDM-producing uropathogenic E. coli XA31 that was found to carry numerous drug resistance genes of different antibiotic classes. The isolate E. coli belongs to ST-101 carrying blaNDM-7 coexisting with several resistance genes blaOXA-1, blaTEM1-A, blaCTX-M15, aac(6'')-Ib-cr, catB3, tetB. Resfinder predicts this and four other plasmid replicons were identified using the Plasfinder in the CGE platform. The high transferable IncX3 plasmid was found to carry the NDM-7 gene. Thus, we the report the combination of NDM-7-ST101-IncX3 in India. The combination of this epidemic clone with NDM-7 is highly required to develop an effective infection control strategy. 相似文献
47.
The inositol 1,4,5-trisphosphate (InsP(3)) receptor is a tetrameric intracellular calcium channel. It is an integral component of the InsP(3) signaling pathway in multicellular organisms, where it regulates cellular calcium dynamics in many different contexts. In order to understand how the primary structure of the InsP(3)R affects its functional properties, the kinetics of Ca(2+)-release in vitro from single point mutants of the Drosophila InsP(3)R have been determined earlier. Among these, the Ka901 mutant in the putative selectivity-filter of the pore is of particular interest. It is non-functional in the homomeric form whereas it forms functional channels (with altered channel properties) when co-expressed with wild-type channels. Here we show that due to its changed functional properties the Ka901 mutant protein has dominant-negative effects in vivo. Cells expressing Ka901:WT channels exhibit much higher levels of cytosolic Ca(2+) upon stimulation as compared with cells over-expressing just the wild-type DmInsP(3)R, thus supporting our in vitro observations that increased Ca(2+) release is a property of heteromeric Ka901:WT channels. Furthermore, ectopic expression of the Ka901 mutant channel in aminergic cells of Drosophila alters electrophysiological properties of a flight circuit and results in defective flight behavior. 相似文献
48.
Sen U Sathnur PB Kundu S Givvimani S Coley DM Mishra PK Qipshidze N Tyagi N Metreveli N Tyagi SC 《American journal of physiology. Cell physiology》2012,303(1):C41-C51
Hydrogen sulfide (H(2)S) has recently been identified as a regulator of various physiological events, including vasodilation, angiogenesis, antiapoptotic, and cellular signaling. Endogenously, H(2)S is produced as a metabolite of homocysteine (Hcy) by cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3MST). Although Hcy is recognized as vascular risk factor at an elevated level [hyperhomocysteinemia (HHcy)] and contributes to vascular injury leading to renovascular dysfunction, the exact mechanism is unclear. The goal of the current study was to investigate whether conversion of Hcy to H(2)S improves renovascular function. Ex vivo renal artery culture with CBS, CSE, and 3MST triple gene therapy generated more H(2)S in the presence of Hcy, and these arteries were more responsive to endothelial-dependent vasodilation compared with nontransfected arteries treated with high Hcy. Cross section of triple gene-delivered renal arteries immunostaining suggested increased expression of CD31 and VEGF and diminished expression of the antiangiogenic factor endostatin. In vitro endothelial cell culture demonstrated increased mitophagy during high levels of Hcy and was mitigated by triple gene delivery. Also, dephosphorylated Akt and phosphorylated FoxO3 in HHcy were reversed by H(2)S or triple gene delivery. Upregulated matrix metalloproteinases-13 and downregulated tissue inhibitor of metalloproteinase-1 in HHcy were normalized by overexpression of triple genes. Together, these results suggest that H(2)S plays a key role in renovasculopathy during HHcy and is mediated through Akt/FoxO3 pathways. We conclude that conversion of Hcy to H(2)S by CBS, CSE, or 3MST triple gene therapy improves renovascular function in HHcy. 相似文献
49.
Srikanth Kotapati Leena Maddukuri Susith Wickramaratne Uthpala Seneviratne Melissa Goggin Matthew G. Pence Peter Villalta F. Peter Guengerich Lawrence Marnett Natalia Tretyakova 《The Journal of biological chemistry》2012,287(46):38800-38811
The 1,N6-(2-Hydroxy-3-hydroxymethylpropan-1,3-diyl)-2′-deoxyadenosine (1,N6-γ-HMHP-dA) adducts are formed upon bifunctional alkylation of adenine nucleobases in DNA by 1,2,3,4-diepoxybutane, the putative ultimate carcinogenic metabolite of 1,3-butadiene. The presence of a substituted 1,N6-propano group on 1,N6-γ-HMHP-dA is expected to block the Watson-Crick base pairing of the adducted adenine with thymine, potentially contributing to mutagenesis. In this study, the enzymology of replication past site-specific 1,N6-γ-HMHP-dA lesions in the presence of human DNA polymerases (hpols) β, η, κ, and ι and archebacterial polymerase Dpo4 was investigated. Run-on gel analysis with all four dNTPs revealed that hpol η, κ, and Dpo4 were able to copy the modified template. In contrast, hpol ι inserted a single base opposite 1,N6-γ-HMHP-dA but was unable to extend beyond the damaged site, and a complete replication block was observed with hpol β. Single nucleotide incorporation experiments indicated that although hpol η, κ, and Dpo4 incorporated the correct nucleotide (dTMP) opposite the lesion, dGMP and dAMP were inserted with a comparable frequency. HPLC-ESI-MS/MS analysis of primer extension products confirmed the ability of bypass polymerases to insert dTMP, dAMP, or dGMP opposite 1,N6-γ-HMHP-dA and detected large amounts of −1 and −2 deletion products. Taken together, these results indicate that hpol η and κ enzymes bypass 1,N6-γ-HMHP-dA lesions in an error-prone fashion, potentially contributing to A→T and A→C transversions and frameshift mutations observed in cells following treatment with 1,2,3,4-diepoxybutane. 相似文献
50.
J. Neurochem. (2012) 122, 1211-1218. ABSTRACT: In this study, we used the GTP cyclohydrolase I-deficient mice, i.e., hyperphenylalaninemic (hph-1) mice, to test the hypothesis that the loss of tetrahydrobiopterin (BH(4) ) in cerebral microvessels causes endothelial nitric oxide synthase (eNOS) uncoupling, resulting in increased superoxide anion production and inhibition of endothelial nitric oxide signaling. Both homozygous mutant (hph-1(-/-) ) and heterozygous mutant (hph-1(+/-) mice) demonstrated reduction in GTP cyclohydrolase I activity and reduced bioavailability of BH(4) . In the cerebral microvessels of hph-1(+/-) and hph-1(-/-) mice, increased superoxide anion production was inhibited by supplementation of BH(4) or NOS inhibitor- L- N(G) -nitro arginine-methyl ester, indicative of eNOS uncoupling. Expression of 3-nitrotyrosine was significantly increased, whereas NO production and cGMP levels were significantly reduced. Expressions of antioxidant enzymes namely copper and zinc superoxide dismutase, manganese superoxide dismutase, and catalase were not affected by uncoupling of eNOS. Reduced levels of BH(4) , increased superoxide anion production, as well as inhibition of NO signaling were not different between the microvessels of male and female mice. The results of our study are the first to demonstrate that, regardless of gender, reduced BH(4) bioavailability causes eNOS uncoupling, increases superoxide anion production, inhibits eNOS/cGMP signaling, and imposes significant oxidative stress in the cerebral microvasculature. 相似文献