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21.
Allurement of herbs as health beneficial foods (physiologically functional foods) and as a source material for the development of new drugs, has led to greater furtherance in the study of herbal medicines during recent years. Plant extracts are being utilized to treat a wide variety of diseases like hepatotoxicity. Premna tomentosa is one such medicinal plant used widely in Indian ayurvedic medicine for the treatment of liver disorders. This study appraised the effectiveness of P. tomentosa leaf extract in protecting the liver against mitochondrial damage induced by acetaminophen, since mitochondrial injury has been investigated as a potential initiator of hepatotoxicity. Normal Wistar strain rats were pre-treated with P. tomentosa extract (750 mg/kg, orally) for 15 days and then intoxicated with acetaminophen (640 mg/kg, orally). Mitochondria were isolated from liver of experimental animals and assessed for the levels of lipid peroxide products, GSH and mitochondrial enzymes (isocitrate dehydrogenase, -keto glutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, NADH dehydrogenase and cytochrome-C-oxidase). The levels of Lipid peroxidation products were increased and the levels of the other assessed parameters were significantly decreased in hepatotoxicity induced animals. Whereas, the levels were brought back to normal in P. tomentosa pre-treated rats, which shows the protective effect of the extract against mitochondrial damage. Presence of anti-oxidant compound d-limonene (58%) in P. tomentosa leaves, which is known to enhance conjugation of toxic metabolites by maintaining liver GSH concentrations may explain the hepatoprotective property of the extract.  相似文献   
22.
Oncidium is a popular ornamental orchid and is produced as a high value cash crop for cut flower sold worldwide. Genetically transformed plants of Oncidium were regenerated after cocultivating protocorm-like bodies (PLBs) with Agrobacterium tumefaciens strain LBA4404 harboring pBI121 with OMADS1. The chopped PLBs pre-cultured for 3?days in darkness produced more kanamycin-resistant PLBs. G10 medium containing 200?mg?l?1 kanamycin was effective for the selection of transformed lines at a frequency of 9%. The rooted plantlets were transferred to pots, acclimated for 3?weeks in the culture room and then moved to the greenhouse. OMADS1 transgene was detected in transgenic lines by PCR, Southern blot analysis and RT-PCR were performed, and the results confirmed that OMADS1 was expressed in these 35S::OMADS1 transgenic plants. CaMV35S::OMADS1 transgenic Oncidium orchid plants flowered significantly earlier, produced more flowers and pseudobulbs than non-transgenic plants. The flower organ conversions were not observed in 35S::OMADS1 transgenic flowers of Oncidium. This is the first report on the ectopic expression of MADS box gene in O. Gower Ramsey using a simple and efficient gene transfer protocol.  相似文献   
23.
At diagnosis, the majority of pancreatic cancer patients present with advanced disease when curative resection is no longer feasible and current therapeutic treatments are largely ineffective. An improved understanding of molecular targets for effective intervention of pancreatic cancer is thus urgent. The Met receptor tyrosine kinase is one candidate implicated in pancreatic cancer. Notably, Met is over expressed in up to 80% of invasive pancreatic cancers but not in normal ductal cells correlating with poor overall patient survival and increased recurrence rates following surgical resection. However the functional role of Met signaling in pancreatic cancer remains poorly understood. Here we used RNA interference to directly examine the pathobiological importance of increased Met signaling for pancreatic cancer. We show that Met knockdown in pancreatic tumor cells results in decreased cell survival, cell invasion, and migration on collagen I in vitro. Using an orthotopic model for pancreatic cancer, we provide in vivo evidence that Met knockdown reduced tumor burden correlating with decreased cell survival and tumor angiogenesis, with minimal effect on cell growth. Notably, we report that Met signaling regulates the secretion of the pro-angiogenic chemokine interleukin-8/CXCL8. Our data showing that the interleukin-8 receptors CXCR1 and CXCR2 are not expressed on pancreatic tumor cells, suggests a paracrine mechanism by which Met signaling regulates interleukin-8 secretion to remodel the tumor microenvironment, a novel finding that could have important clinical implications for improving the effectiveness of treatments for pancreatic cancer.  相似文献   
24.
One of the focuses in current cancer chemoprevention studies is the search for nontoxic chemopreventive agents that inhibit the initiation of malignant transformation. Cancer biomarkers are quantifiable molecules involved in the physiologic or pathologic events occurring between exposure to carcinogens and the development, progression of cancer. Biomarkers may be the consequence of a continuous process, such as increased cell mass, or a discrete event, such as genetic mutation. Analysis of tumor markers can be used as an indicator of tumor response to therapy. Gallic acid is a naturally available polyphenol, possess strong antioxidant activity with a capacity to inhibit the formation of tumors in several cancer models. In the present study, we investigated the antiproliferative effect of gallic acid during diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) in male wistar albino rats. DEN treatment resulted in increased levels of aspartate transaminase, alanine transaminase, alkaline phosphatase, acid phosphatase, lactate dehydrogenase, gamma-glutamyltransferase, 5'-nucleotidase, bilirubin, alpha-fetoprotein, carcinoembryonic antigen, argyophillic nucleolar organizing regions, and proliferating cell nuclear antigen. Gallic acid treatment significantly attenuated these alterations and decreased the levels of AgNORs and PCNA. These finding suggests that gallic acid is a potent antiproliferative agent against DEN-induced HCC.  相似文献   
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The maintenance of a differentiated chondrocyte phenotype is influenced by several factors of which signal transduction of extracellular stimuli through the cell membrane is of major interest. One important group of membrane-bound proteins which are involved in transmembrane signal transduction are ion channels. Human articular chondrocytes were obtained from osteoarthritic femoral condyles. Cells were released from the surrounding matrix and cultivated under standard conditions. We investigated gene expression of 12 members of the TRP ion channel family of freshly prepared (passage 0; P0) and in vitro propagated human articular chondrocytes (passage 2; P2) using conventional and real-time PCR (RT-PCR). In addition, the protein appearance of four TRP channels was demonstrated by immunofluorescence and western blotting. Chondrocyte differentiation was monitored by quantification of collagen type-II, type-I, and aggrecan gene expression. By conventional PCR, 8 channels could be detected, of which some displayed a heterogeneous PCR pattern. RT-PCR quantification revealed that TRPC1 was expressed on the same level in P0 and P2 chondrocytes while gene expression of TRPC3 and TRPC6 was elevated in passage 2 cells. TRPM5, TRPM7, and TRPV1 displayed an enhanced gene expression in freshly isolated chondrocytes. Immunofluorescence signal intensity of all four investigated TRP proteins was consistent with the corresponding gene expression data. In the present study, a correlation between the appearance of some members of the TRP ion channel family and the state of de-differentiation of osteoarthritic articular chondrocytes was shown. A possible direct involvement in the process of chondrocyte de-differentiation has to be investigated in further studies.  相似文献   
28.

Background  

Plant Growth Promoting Rhizobacteria (PGPR), Pseudomonas fluorescens strain KH-1 was found to exhibit plant growth promotional activity in rice under both in-vitro and in-vivo conditions. But the mechanism underlying such promotional activity of P. fluorescens is not yet understood clearly. In this study, efforts were made to elucidate the molecular responses of rice plants to P. fluorescens treatment through protein profiling. Two-dimensional polyacrylamide gel electrophoresis strategy was adopted to identify the PGPR responsive proteins and the differentially expressed proteins were analyzed by mass spectrometry.  相似文献   
29.
Insect Barcode Information System called as Insect Barcode Informática (IBIn) is an online database resource developed by the National Bureau of Agriculturally Important Insects, Bangalore. This database provides acquisition, storage, analysis and publication of DNA barcode records of agriculturally important insects, for researchers specifically in India and other countries. It bridges a gap in bioinformatics by integrating molecular, morphological and distribution details of agriculturally important insects. IBIn was developed using PHP/My SQL by using relational database management concept. This database is based on the client– server architecture, where many clients can access data simultaneously. IBIn is freely available on-line and is user-friendly. IBIn allows the registered users to input new information, search and view information related to DNA barcode of agriculturally important insects.This paper provides a current status of insect barcode in India and brief introduction about the database IBIn.

Availability

http://www.nabg-nbaii.res.in/barcode  相似文献   
30.
Nearly 5 000 aphid species damage crops, either by sucking plant sap or as disease‐transmitting vectors. Microsatellites are used for understanding molecular diversity and eco‐geographical relationships among aphid species. Expressed sequence tag (EST)‐microsatellite motifs were identified through an in silico approach using inbuilt simple sequence repeat mining tools in aphid EST dataset. Microsatellite mining revealed one in every five aphid genes as containing a repeat motif, and out of 9 290 EST microsatellites mined from Aphis gossypii Glover and Acyrthosiphon pisum (Harris) (both Hemiptera: Aphididae), 80% were of A and/or T (AT, ATA, AAT, AATA, and ATTT) motifs, and the rest contained G and/or C motifs. All microsatellite sequences were annotated using BLAST. Primers for EST microsatellites were designed using the Primer 3.0 tool. 106 primer pairs of both dinucleotide repeats (DNRs) and trinucleotide repeats (TNRs), representing open reading frames (ORFs) and untranslated regions (UTRs), were synthesized to amplify 15 aphid species belonging to the subfamily Aphidinae, collected from diverse hosts. Four hundred forty‐five polymorphic alleles were amplified. Fifty TNR and 23 DNR microsatellites amplified across the species studied. Polymorphism information content values of microsatellites ranged from 0.23 to 0.91, amplifying 2–16 alleles. Genetic similarity indices were estimated using the ‘NTSYS‐pc’ software package. Unweighted pair group with arithmetic mean and principal component analysis resolved taxonomic relationships of the aphid species studied. The new aphid microsatellites developed will provide valuable information to researchers to study Indian aphid species diversity and genetic relationships.  相似文献   
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