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161.
Effect of the purinergic receptor P2X7 on Chlamydia infection in cervical epithelial cells and vaginally infected mice 总被引:2,自引:0,他引:2
Darville T Welter-Stahl L Cruz C Sater AA Andrews CW Ojcius DM 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(6):3707-3714
Ligation of the purinergic receptor, P2X7R, with its agonist ATP has been previously shown to inhibit intracellular infection by chlamydiae and mycobacteria in macrophages. The effect of P2X7R on chlamydial infection had never been investigated in the preferred target cells of chlamydiae, cervical epithelial cells, nor in vaginally infected mice. In this study, we show that treatment of epithelial cells with P2X7R agonists inhibits partially Chlamydia infection in epithelial cells. Chelation of ATP with magnesium or pretreatment with a P2X7R antagonist blocks the inhibitory effects of ATP. Similarly to previous results obtained with macrophages, ATP-mediated inhibition of infection in epithelial cells requires activation of host-cell phospholipase D. Vaginal infection was also more efficient in P2X7R-deficient mice, which also displayed a higher level of acute inflammation in the endocervix, oviduct, and mesosalpingeal tissues than in infected wild-type mice. However, secretion of IL-1beta, which requires P2X7R ligation during infection by other pathogens, was decreased mildly and only at short times of infection. Taken together, these results suggest that P2X7R affects Chlamydia infection by directly inhibiting infection in epithelial cells, rather than through the ability of P2X7R to modulate IL-1beta secretion. 相似文献
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164.
Zhu XY Mardenborough LG Li S Khan A Zhang W Fan P Jacob M Khan S Walker L Ablordeppey SY 《Bioorganic & medicinal chemistry》2007,15(2):686-695
Isosteres of cryptolepine (1) were synthesized and evaluated for their antiinfective activities. Overall, the sulfur isostere, 5-methyl benzothieno[3,2-b]quinolinium salt (5b), was equipotent to 1 and has shown no cytotoxicity at 23.8 microg/mL. Compound 5b was also found to have a broad spectrum of activity. Both the carbon and oxygen isosteres were less potent than cryptolepine. A limited library of 2-substituted analogs of 5b has been synthesized and evaluated in antifungal screens but did not show increase in potency compared to the unsubstituted 5b. Similarly, evaluation of tricyclic benzothieno[3,2-b]pyridines while showing promise in individual screens did not produce an overall increase in potency. Overall, the evaluation of the activities of 5b compared with standard antifungal/anti-protozoal agents suggests that the benzothienoquinoline scaffold could serve as a lead for optimization. 相似文献
165.
Fui Chin Chong Beng Ti Tey Zanariah Mohd Dom Kok Hing Cheong Budiatman Satiawihardja Mohd Nordin Ibrahim Russly Abdul Rahman Dayang Radiah Awang Biak Tau Chuan Ling 《Biotechnology and Bioprocess Engineering》2007,12(3):250-256
Rice bran lipase (RBL) was delipidated to enhance its stability in organic solvent and its esterification activity at elevated
temperature. The esterification activity of delipidated RBL increased as temperature was increased from 45 to 65°C. The esterification
activity of delipidated RBL at 65°C was about 14 times greater than that of the non-delipidated RBL. As temperature was further
increased to 75°C, the non-delipidated RBL lost all esterification activity, whereas the delipidated RBL retained approximately
48% of its esterilication activity. The delipidated RBL maintained a relative esterification activity greater than 80% after
16 h of incubation in hexane, whereas the non-delipidated RBL maintained a relative esterification activity of only 50%. A
method for production of acylglycerol using delipidated RBL to esterify palm oil fatty acid distillate (PFAD) with glycerol
in hexane was successfully developed. The effects of reaction temperatures and type of water removal agents (silica gel and
molecular sieve) on the degree of esterification were also examined. A 4 h reaction at 65°C, catalyzed by delipidated RBL
and using silica gel as the water removal agent resulted in 53.8% esterification. Thin layer chromatography analysis suggested
that the esterified product was primarily comprised of mono-and di-acylglycerols. 相似文献
166.
Cholinergic anti-inflammatory pathway activity and High Mobility Group Box-1 (HMGB1) serum levels in patients with rheumatoid arthritis 总被引:2,自引:0,他引:2
Goldstein RS Bruchfeld A Yang L Qureshi AR Gallowitsch-Puerta M Patel NB Huston BJ Chavan S Rosas-Ballina M Gregersen PK Czura CJ Sloan RP Sama AE Tracey KJ 《Molecular medicine (Cambridge, Mass.)》2007,13(3-4):210-215
High Mobility Group Box-1 (HMGB1) is a cytokine implicated in the pathogenesis of rheumatoid arthritis (RA) and other inflammatory diseases. The cholinergic anti-inflammatory pathway, a vagus nerve-dependent mechanism, inhibits HMGB1 release in experimental disease models. Here, we examine the relationship between vagus nerve activity and HMGB1 in patients with RA. We compared RR interval variability, an index of cardiac vagal modulation, HMGB1 and hsCRP serum levels, and disease activity scores in thirteen RA patients and eleven age- and sex-matched controls. In RA patients, serum levels of HMGB1 and hsCRP were elevated as compared with controls (HMGB1=71 ng/mL [45-99] vs. 18 ng/mL [0-40], P<0.0001; hsCRP=14.5 mg/L [0.7-59] vs. 1 mg/L [0.4-2.9], P<0.001). RR interval variability in RA patients was significantly decreased as compared with controls (HF=38 msec2 [14-80] vs. 288 msec2 [38-364], P<0.0001; rMSSD=20.9+/-9.79 msec, 52.6+/-35.3 msec, P<0.01). HMGB1 levels and RR interval variability were significantly related (rho=-0.49, P<0.01). HMGB1 serum levels significantly correlated with disease activity scores (DAS-28) in patients with RA (P=0.004). The study design does not enable a determination of causality, but the results are consistent with the hypothesis that decreased cholinergic anti-inflammatory pathway activity is associated with increased HMGB1 levels in patients with RA. 相似文献
167.
Rahmah Noordin Makoto Itoh Eisaku Kimura Rohana Abdul Rahman Balachandran Ravindran Rohela Mahmud Taniawati Supali Mirani Weerasooriya 《Filaria journal》2007,6(1):1-4
Background
Sustainable and equitable health programmes require a grounded understanding of the context in which they are being implemented. This socio-cultural understanding is pivotal for effective delivery of elimination programmes. Standardised valid methods are needed for gathering authentic socio-cultural insights. The currently recommended protocol for collecting Lymphatic Filariasis (LF) related socio-cultural data, while moving in the right direction, is inadequate. To collect data which provides an understanding of local health beliefs and practices, and communities' understanding of LF, techniques must be developed that are both valid and time efficient. An approach developed in the Pacific provides a basic snapshot of socio-cultural insights which are crucial to the development of relevant and sustainable health education and elimination programmes.Summary
The increasing interest in socio-cultural LF research presents a unique opportunity for coupling socio-cultural and bio-medical understandings of LF. To address the backlog in the socio-cultural sphere will require investment of time and effort to integrate valid qualitative approaches into current data collection methodologies. 相似文献168.
Multiple sequence alignment was performed against eight proteases from the Flaviviridae family using ClustalW to illustrate conserved domains. Two sets of prediction approaches were applied and the results compared. Firstly, secondary structure prediction was performed using available structure prediction servers. The second approach made use of the information on the secondary structures extracted from structure prediction servers, threading techniques and DSSP database of some of the templates used in the threading techniques. Consensus on the one-dimensional secondary structure of Den2 protease was obtained from each approach and evaluated against data from the recently crystallised Den2 NS2B/NS3 obtained from the Protein Data Bank (PDB). Results indicated the second approach to show higher accuracy compared to the use of prediction servers only. Thus, it is plausible that this approach is applicable to the initial stage of structural studies of proteins with low amino acid sequence homology against other available proteins in the PDB. 相似文献
169.
Biodegradable polyesters such as poly(epsilon-caprolactone) (PCL) have a number of biomedical applications; however, their usage is often limited by a lack of biological functionality. In this paper, a PCL-based polymer containing pendent groups activated by 4-nitrophenyl chloroformate (NPC) and reactive toward primary amines has been cast into thin films. The reactivity of the films toward poly(l-lysine) and the cell adhesion peptide, GRGDS, was assessed, and their cell adhesive capabilities were characterized. ATR-FTIR analysis found that NPC functional groups were present on the surface of the cast film, and the synthesis, conjugation, and visualization of a fluorescent molecule on these films further demonstrated the success of this functionalization methodology. The immersion of these films into a solution of either poly(l-lysine) (PLL) or GRGDS in PBS (pH 7.4) and subsequent 3T3 fibroblast adhesion studies demonstrated significant improvement in cell adhesion and spreading over films cast from unmodified PCL. This investigation has shown that this novel NPC-containing polymer can be utilized in many applications where increased cellular adhesion is required, or the coupling of specific molecules to polymer surfaces is of interest. 相似文献
170.
Mao Yihang Hafeez Abdul Pan Taowen Wu Chaorong Wang Lei Muramoto Joji Shennan Carol Cai Kunzheng Tian Jihui 《Plant and Soil》2022,477(1-2):539-552
Plant and Soil - Anaerobic soil disinfestation (ASD) has been proven to be an effective and environmentally friendly method for controlling soil-borne plant diseases. Mechanisms of ASD-mediated... 相似文献