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991.
992.
BACKGROUND: Surgical stress can lead to bacterial translocation from the intestine into systemic circulation. Adherence of bacteria onto the glycoconjugates of the brush border membrane (BBM) and surfactant coat (SLP) of the mucosal cells is the first step in the translocation of luminal bacteria. Our earlier study showed that surgical manipulation of the intestine results in oxidative stress leading to structural and functional alterations in the mucosa. This study looks at the effect of surgical manipulation on the glycoconjugate alterations of SLP and BBM. MATERIALS AND METHODS: SLP and BBM were isolated from control and after surgical manipulation and the sugar composition was analyzed. Bacterial adherence using E. coli isolated from cecum was compared after coating microtiter plates with SLP or BBM isolated from control and after surgical manipulation. RESULTS: An increase in various sugars was seen after surgical manipulation both in SLP and BBM and this increase was maximum at 12 h after surgery. These alterations increased bacterial adherence onto SLP and BBM. Inhibiting superoxide generation by allopurinol treatment prior to surgical manipulation prevented glycosylation alteration and bacterial adherence. CONCLUSION: Surgical manipulation results in altered glycoconjugates of SLP and BBM which leads to increased bacterial adherence. These alterations are probably brought about by oxygen-free radicals. This is clinically significant because postsurgical complications such as sepsis may be brought about by altered glycosylation. 相似文献
993.
994.
Synthesis and study of antibacterial and antifungal activities of novel 1-[2-(benzoxazol-2-yl)ethoxy]- 2,6-diarylpiperidin-4-ones 总被引:3,自引:0,他引:3
Ramalingan C Balasubramanian S Kabilan S Vasudevan M 《European journal of medicinal chemistry》2004,39(6):527-533
Some novel benzoxazolylethoxypiperidones have been synthesized and their antibacterial activity against streptococcus faecalis, bacillus subtilis, escherichia coli, staphylococcus aureus aand pseudomonas aeruginosa and antifungal activity against Candida-6, Candida albicans, Aspergillus niger, Candida-51 and Aspergillus flavus were evaluated. Compounds 37, 38 and 39 exerted potent in vitro antibacterial activity against Streptococcus faecalis while compounds 40 and 41 exhibited potent in vitro antifungal activity against Candida-51. 相似文献
995.
996.
William?H?Hall Ramanathan?Ramachandran Samir?Narayan Ashesh?B?Jani Srinivasan?VijayakumarEmail author 《BMC cancer》2004,4(1):94
Background
Uncertainty regarding comorbid illness, and ability to tolerate aggressive therapy has led to minimal enrollment of elderly cancer patients into clinical trials and often substandard treatment. Increasingly, comorbid illness scales have proven useful in identifying subgroups of elderly patients who are more likely to tolerate and benefit from aggressive therapy. Unfortunately, the use of such scales has yet to be widely integrated into either clinical practice or clinical trials research. 相似文献997.
The reliability of skin biopsy with measurement of intraepidermal nerve fiber density 总被引:3,自引:0,他引:3
Smith AG Howard JR Kroll R Ramachandran P Hauer P Singleton JR McArthur J 《Journal of the neurological sciences》2005,228(1):65-69
Intraepidermal nerve fiber density (IENFD) is a sensitive measure of small fiber injury, and holds promise as a clinical trial endpoint measure. A total of 48 punch biopsies were obtained from 22 patients. Tissue was sectioned and stained with PGP9.5. The relative intertrial variability (RIV) of IENFD measurements for each section and punch made by two different observers was determined (interobserver variability). Intraobserver variability (same observer measuring twice) was determined for 50% of the sections and punches. Sections from 12 punch biopsies were also stained at a second laboratory. The effect of the number of sections counted and processing site on reproducibility was investigated. A total of 223 sections were analyzed. The mean IENFD was 6.7 fibers/mm. Mean (+/-standard deviation) interobserver variability was 9.6%+/-9.4 for each biopsy site and 10.2%+/-11.9 for individual sections. Mean intraobserver variability was 9.6%+/-8.9 for biopsies, and 8.8%+/-9.0 for sections. There was no significant difference in IENFD for tissue stained at different laboratories. Intraclass correlation coefficients were greater than 0.98 for each comparison. There was no relationship between absolute IENFD and reproducibility. Reproducibility was highest when four sections were counted. IENFD measurement is highly reproducible. At least four sections should be analyzed. Reliability does not vary with severity of disease. These findings suggest IENFD may be a useful endpoint measure in future neuropathy treatment trials. 相似文献
998.
Expression profiles of apoptotic genes induced by curcumin in human breast cancer and mammary epithelial cell lines 总被引:2,自引:0,他引:2
Ramachandran C Rodriguez S Ramachandran R Raveendran Nair PK Fonseca H Khatib Z Escalon E Melnick SJ 《Anticancer research》2005,25(5):3293-3302
Curcumin (diferuloyl methane), the yellow-colored dietary pigment from the rhizomes of turmeric, has been recognized as a chemopreventive agent because of its antitumor, antioxidant and antiproliferative effects. The cytotoxic, apoptotic and gene regulatory effects of both turmeric and curcumin were investigated in the MCF-7 human breast cancer carcinoma cell line and compared with the effects in MCF-10A human mammary epithelial cells. MCF-7 cells were more sensitive to turmeric and curcumin than MCF-10A cells. MCF-10A cells retained comparatively less curcumin in the medium than MCF- 7 cells after 24 h, thereby reducing the cytotoxic effect. Curcumin induced a significantly higher percentage of apoptosis in MCF-7 than MCF-10A cells at all doses. Microarray hybridization of Clonetech apoptotic arrays with labeled first-strand probes of total RNA was performed to identify and characterize the genes regulated by curcumin in tumor cells. Of the 214 apoptosis-associated genes in the array, the expression of 104 genes was altered by curcumin treatment. The gene expression was altered up to 14-fold levels in MCF-7 as compared to only up to 1.5-fold in the MCF-10A cell line by curcumin. Curcumin up-regulated (>3 fold) 22 genes and down-regulated (<3-fold) 17 genes at both 25 microg/ml and 50 microg/ml doses in the MCF-7 cell line. The up-regulated genes include HIAP1, CRAF1, TRAF6, CASP1, CASP2, CASP3, CASP4, HPRT, GADD45, MCL-1, NIP1, BCL2L2, TRAP3, GSTP1, DAXX, PIG11, UBC, PIG3, PCNA, CDC10, JNK1 and RBP2. The down-regulated genes were TRAIL, TNFR, AP13, IGFBP3, SARP3, PKB, IGFBP, CASP7, CASP9, TNFSF6, TRICK2A, CAS, TRAIL-R2, RATS1, hTRIP, TNFb and TNFRSF5. While a dose-dependent gene expression change was noticed in some genes, opposite regulatory effects were induced by different curcumin doses in three apoptotic genes. These results suggest that curcumin induces apoptosis in breast cancer cells by regulation of multiple signaling pathways, indicating its potential use for prevention and treatment of cancer. 相似文献
999.
Outdoor, indoor, and personal exposure to VOCs in children 总被引:1,自引:0,他引:1
Adgate JL Church TR Ryan AD Ramachandran G Fredrickson AL Stock TH Morandi MT Sexton K 《Environmental health perspectives》2004,112(14):1386-1392
We measured volatile organic compound (VOC) exposures in multiple locations for a diverse population of children who attended two inner-city schools in Minneapolis, Minnesota. Fifteen common VOCs were measured at four locations: outdoors (O), indoors at school (S), indoors at home (H), and in personal samples (P). Concentrations of most VOCs followed the general pattern O approximately equal to S < P less than or equal to H across the measured microenvironments. The S and O environments had the smallest and H the largest influence on personal exposure to most compounds. A time-weighted model of P exposure using all measured microenvironments and time-activity data provided little additional explanatory power beyond that provided by using the H measurement alone. Although H and P concentrations of most VOCs measured in this study were similar to or lower than levels measured in recent personal monitoring studies of adults and children in the United States, p-dichlorobenzene was the notable exception to this pattern, with upper-bound exposures more than 100 times greater than those found in other studies of children. Median and upper-bound H and P exposures were well above health benchmarks for several compounds, so outdoor measurements likely underestimate long-term health risks from children's exposure to these compounds. 相似文献
1000.