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51.
Many herbs and spices are known to modulate the immune system and have been shown to restore the immunity in immuno-compromised individuals. Spices generally used to increase the taste and flavor of food also has the history of usage as an ayurvedic medicine. Therefore to explore the health modulating effects of Cuminum cyminum and to identify the active compound, immunomodulatory properties were evaluated using flowcytometry and ELISA in normal and immune-suppressed animals. C. cyminum and compound 1 stimulated the T cells and Th1 cytokines expression in normal animals. Swiss albino mice subjected to Cyclosporine-A induced immune-suppression were dosed orally with C. cyminum (25, 50, 100 and 200 mg/kg) on consecutive days. The results showed that administration significantly increased T cells (CD4 and CD8) count and Th1 predominant immune response in a dose dependent manner thereby suggesting immunomodulatory activity through modulation of T lymphocytes expression. In restraint stress induced immune-suppressed animals, compound 1 countered the depleted T lymphocytes, decreased the elevated corticosterone levels and size of adrenal glands and increased the weight of thymus and spleen. Based on the data we may conclude that C. cyminum is a potent immunomodulator and may develop as a lead to recover the immunity of immuno-compromised individuals.  相似文献   
52.
The main active components and genetic profile of 15 selected accessions of Withania somnifera Dunal. were analysed. Ethanolic extract of the dried roots/leaves of the plant was concentrated under pressure at 50+/-5 degrees C and was analysed for main compounds (withanolides and withaferin A) by HPLC. All the main components were found to be present in accessions (AGB 002, AGB 009, RSS 009, RSS 033). Correlation of these main components with their genetic factors, was undertaken using AFLP (amplified fragment length polymorphism) markers. Among 64 primers 7 yielded optimum polymorphism. A total of 913 polymorphic peaks were generated using these primers. Jaccard's similarity coefficient indicated that accessions having almost the same active compounds clustered together. The present study demonstrates that AFLP can be successfully used to resolve the correlation of AFLP data with the presence of secondary metabolites.  相似文献   
53.
The effect of soil flooding on photosynthesis, transpiration and stomatal conductance of Jatropha curcas seedlings were studied under natural environmental variables. Soil flooding reduced photosynthesis (P N), transpiration (E) and stomatal conductance (gs) in response to leaf positions of Jatropha curcas plants. Based on the results, we conclude that decrease in stomatal opening and stomatal limitation of photosynthesis, followed by decrease in individual leaf area are the main causes of reductions in carbon uptake of flooded seedlings. A mathematical relationship was successfully developed to describe photosynthesis, transpiration and stomatal response of Jatropha under soil flooding stress.  相似文献   
54.
The therapeutic potential of stem cells is limited by the non-uniformity of their phenotypic state. Thus it would be advantageous to noninvasively monitor stem cell status. Driven by this challenge, we employed multidimensional multiphoton microscopy to quantify changes in endogenous fluorescence occurring with pluripotent stem cell differentiation. We found that global and cellular-scale fluorescence lifetime of human embryonic stem cells (hESC) and murine embryonic stem cells (mESC) consistently decreased with differentiation. Less consistent were trends in endogenous fluorescence intensity with differentiation, suggesting intensity is more readily impacted by nuances of species and scale of analysis. What emerges is a practical and accessible approach to evaluate, and ultimately enrich, living stem cell populations based on changes in metabolism that could be exploited for both research and clinical applications.  相似文献   
55.
Fusion systems are known to increase the expression of difficult to express recombinant proteins in soluble form to facilitate their purification. Rabies glycoprotein was also tough to express at sufficient level in soluble form in both E. coli and plant. The present work was aimed to over-express and purify this membrane protein from soluble extract of E. coli. Fusion of Small Ubiqutin like Modifier (SUMO) with rabies glycoprotein increased ~1.5 fold higher expression and ~3.0 fold solubility in comparison to non-fused in E. coli. The SUMO fusion also simplified the purification process. Previously engineered rabies glycoprotein gene in tobacco plants provides complete protection to mice, but the expression was very low for purification. Our finding demonstrated that the SUMO-fusion was useful for enhancing expression and solubility of the membrane protein and again proves to be a good alternative technology for applications in biomedical and pharmaceutical research.  相似文献   
56.
We investigated the efficacy of a powerful antagonist of bombesin/gastrin-releasing peptide (BN/GRP) RC-3940-II administered as a single agent or in combination with cytotoxic agents on the growth of HT-29, HCT-116 and HCT-15 human colon cancer in vitro and in vivo. GRP-receptor mRNA and protein were found in all three cell lines tested. Exposure of HT-29 cells to 10 μM RC-3940-II led to an increase in the number of cells blocked in S phase and G2/M and cells with lower G0/G1 DNA content. Similar changes on the cell cycle traverse of HT-29 cells could also be seen at lower concentrations of RC-3940-II (1 μM) after pretreatment with 100 nM GRP (14–27), indicating a dose-dependent mechanism of action based on the blockage of BN/GRP induced proliferation of tumor cells at lower concentrations. Daily in vivo treatment with BN/GRP antagonist RC-3940-II decreased the volume of HT-29, HCT-116 and HCT-15 tumors xenografted into athymic nude mice by 25 to 67% (p < 0.005). Combined treatment with RC-3940-II and chemotherapeutic agents 5-FU and irinotecan resulted in a synergistic tumor growth suppression of HT-29, HCT-116 and HCT-15 xenografts by 43% to 78%. In HT-29 and HCT-116 xenografts the inhibition for the combinations of RC-3940-II and irinotecan vs. single substances (p < 0.05) was significantly greater. These findings support the use of RC-3940-II as an anticancer agent and may help to design clinical trials using RC-3940-II in combinations with cytotoxic agents.  相似文献   
57.
A rapid and sensitive gold-nanobioprobe based immunoassay format has been presented for the detection of capsular Vi polysaccharide of Salmonella enterica serovar Typhi (surface antigen) using anti-Vi antibodies. The Vi antigen was extracted from serovar Typhi cells, under the optimised growth conditions for its over-expression. Anti-Vi antibodies were produced and conjugated with gold nanoparticles (GNPs) of definite size (~30 nm), which served as the nano-bioprobe in the detection system. A sandwich immunoassay was developed using nitrocellulose dot blot comb (8/12 wells) membranes immobilized with anti-Salmonella antibodies at the optimal concentration (43 ng spot(-1)). The Vi antigen in the clinical isolates, spiked samples and also in the standard strain (serovar Typhi Ty2) was detected by measuring the colour intensity of GNPs and correlating it with the concentration of serovar Typhi in samples. Using this developed immunoassay technique Vi positive serovar Typhi strains could be detected with a sensitivity of up to 10(2) cells mL(-1) in the clinical isolates as well as in the spiked samples. The developed immunoassay technique could be useful for the detection of typhoid fever and may be important from an epidemiological point of view.  相似文献   
58.
The diversity of Ags targeted by T cells in autoimmune diabetes is unknown. In this study, we identify and characterize a limited number of naturally processed peptides from pancreatic islet beta-cells selected by diabetogenic I-A(g7) molecules of NOD mice. We used insulinomas transfected with the CIITA transactivator, which resulted in their expression of class II histocompatibility molecules and activation of diabetogenic CD4 T cells. Peptides bound to I-A(g7) were isolated and examined by mass spectrometry: some peptides derived from proteins present in secretory granules of endocrine cells, and a number were shared with cells of neuronal lineage. All proteins to which peptides were identified were expressed in beta cells from normal islets. Peptides bound to I-A(g7) molecules contained the favorable binding motif characterized by acidic amino acids at the P9 position. The draining pancreatic lymph nodes of prediabetic NOD mice contained CD4 T cells that recognized three different natural peptides. Furthermore, four different peptides elicited CD4 T cells, substantiating the presence of such self-reactive T cells. The overall strategy of identifying natural peptides from islet beta-cells opens up new avenues to evaluate the repertoire of self-reactive T cells and its role in onset of diabetes.  相似文献   
59.
A heat-activated MAP kinase (HAMK), immunologically related to the extracellular signal-regulated kinase (ERK) super-family of protein kinases, has been identified in BY2 cells of tobacco. The activation of HAMK at 37 degrees C was transient and detected within 2 min and reached a maximum level within 5 min. Ca(2+) chelators and channel blockers, and the known inhibitors of MEK, a MAP kinase kinase, prevented the heat activation of HAMK. This suggests that HAMK activation is part of a heat-triggered MAP kinase cascade that requires Ca(2+) influx. The heat shock protein HSP70 accumulated at 37 degrees C, but not when HAMK activation was prevented with the inhibitors of MEK or with Ca(2+) chelators or channel blockers. As previously shown for heat activation of HAMK, heat-induced accumulation of HSP70 requires membrane fluidization and reorganization of cytoskeleton. We concluded that heat-triggered HAMK cascade might play an essential role in the launching of heat shock response and hsp gene expression in tobacco cells.  相似文献   
60.
OBJECTIVE: To determine the utility of imprint cytology (IC) in providing an early presumptive diagnosis of clinically suspected cervical carcinoma. STUDY DESIGN: A total of 219 clinically suspicious cervical cancer cases underwent Pap test, punch biopsy and IC at the same sitting. Correlations were performed between these diagnostic modalities to determine the sensitivity and specificity of IC in diagnosis of cervical cancer. RESULTS: The overall accuracy of IC in detecting cervical cancers was 96.2%. About 78% of squamous cell carcinomas (SCC), 60% of adenocarcinomas and 100% of small cell carcinoma could be accurately typed on imprints. Twelve malignant lesions were diagnosed on IC among 26 unsatisfactory biopsies. Although there was no false positive result, 3.5% false negative diagnoses were given on IC. The sensitivity and specificity of imprint smear cytology to detect malignancy was 96.2% and 100%. Agreement between imprint cytology and Pap smear diagnosis of malignancy was 95.3%. kappa Statistics revealed excellent agreement between imprints and biopsies and between imprints and Pap smears in diagnosis of malignant lesions. CONCLUSION: IC can be used as an adjunctive technique for an early and reliable preliminary presumptive diagnosis of cancer of the uterine cervix.  相似文献   
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