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61.
Establishment of forskolin yielding transformed cell suspension cultures of Coleus forskohlii as controlled by different factors 总被引:1,自引:0,他引:1
Suspension cultures derived from gall calli which were obtained following infection with Agrobacterium tumefaciens (C58) were established in Coleus forskohlii. Cell line selection following single cell cloning or cell aggregate cloning was carried out to select cell lines capable of fast growth and for producing high level of forskolin. A fast growing cell line (GSO-5/7) thus selected was found to accumulate 0.021% forskolin in 42 days. The effect of cultural conditions on cell growth was studied to identify factors influencing biomass yield. Cell growth in suspension was found to be influenced significantly by carbon source, initial cell density and light or dark condition. Optimal cell growth (20 fold increase in biomass in a 42 day period) was obtained when the cells were grown in dark condition in B5O media containing 3% sucrose as sole carbon source with an initial cell density of 1.5 x 10(5) cells per ml. Forskolin accumulation was maximum (0.021%) in the stationary phase of cell growth. These suspension cultures showed continuous and stable production of forskolin. 相似文献
62.
M K Gupta H V Chauhan G J Jha K K Singh 《Indian journal of experimental biology》1990,28(11):1021-1025
Dinitrofluorobenzene (DNFB) contact-sensitivity test and leucocyte adherence inhibition (LAI) test were performed in this study as in vivo and in vitro tests to measure the cell-mediated immunity (CMI) in chickens subjected to stimulation of reticuloendothelial (RE) system, depletion of RE system and other experimental groups after being challenged with Marek's disease (MD) virus. It was found that CMI was lower in the birds with depleted RE system and infected control birds, whereas CMI was higher in the birds with activated RE system and vaccinated birds as revealed by DNFB contact-sensitivity test. In cases of LAI test, the number of LAI-positive birds were highest in the chicks with depleted RE system particularly in 3rd and 4th month of age, when the incidence of MD was also maximum. 相似文献
63.
Palwinder Singh Jatinder Kaur Bhawna Yadav Sneha Sudha Komath 《Bioorganic & medicinal chemistry》2009,17(11):3973-3979
In order to search for MDR modulators, rationally designed acridone derivatives were investigated for their effect on influx or efflux of Rhodamine6G (R6G) in CAI4 cells. Results of these investigations indicate that in presence of compound 12, inhibition of growth of CAI4 cells and also an increased influx/efflux of R6G in CAI4 cells have been observed. This seems to be occurring due to the cell wall rupturing of Candida albicans. Compound 12 may be a suitable candidate for candidiasis therapy. 相似文献
64.
Inflammation is a known mechanism that facilitates HIV acquisition and the spread of infection. In this study, we evaluated whether curcumin, a potent and safe anti-inflammatory compound, could be used to abrogate inflammatory processes that facilitate HIV-1 acquisition in the female genital tract (FGT) and contribute to HIV amplification. Primary, human genital epithelial cells (GECs) were pretreated with curcumin and exposed to HIV-1 or HIV glycoprotein 120 (gp120), both of which have been shown to disrupt epithelial tight junction proteins, including ZO-1 and occludin. Pre-treatment with curcumin prevented disruption of the mucosal barrier by maintaining ZO-1 and occludin expression and maintained trans-epithelial electric resistance across the genital epithelium. Curcumin pre-treatment also abrogated the gp120-mediated upregulation of the proinflammatory cytokines tumor necrosis factor-α and interleukin (IL)-6, which mediate barrier disruption, as well as the chemokines IL-8, RANTES and interferon gamma-induced protein-10 (IP-10), which are capable of recruiting HIV target cells to the FGT. GECs treated with curcumin and exposed to the sexually transmitted co-infecting microbes HSV-1, HSV-2 and Neisseria gonorrhoeae were unable to elicit innate inflammatory responses that indirectly induced activation of the HIV promoter and curcumin blocked Toll-like receptor (TLR)-mediated induction of HIV replication in chronically infected T-cells. Finally, curcumin treatment resulted in significantly decreased HIV-1 and HSV-2 replication in chronically infected T-cells and primary GECs, respectively. All together, our results suggest that the use of anti-inflammatory compounds such as curcumin may offer a viable alternative for the prevention and/or control of HIV replication in the FGT. 相似文献
65.
The enzymes involved in the protection of plant metabolism in presence of azo dye was characterized by studying activities of the role of antioxidant enzymes in the hairy roots (HRs) of Physalis minima L. during degradation of an azo dye, Reactive Black 8 (RB8). When the HRs were exposed to RB8 (30 mg L?1), a nine fold increase in SOD activity was observed after 24 h, while 22 and 50 fold increase in activity was observed for POX and APX respectively after 72 h, whereas there was no significant change in activity of CAT. The activation of different antioxidant enzymes at different time intervals under dye stress suggests the synchronized functioning of antioxidant machinery to protect the HRs from oxidative damage. FTIR analysis confirmed the degradation of dye and the non-toxic nature of metabolites formed after dye degradation was confirmed by phytotoxicity study. 相似文献
66.
Fernanda Fortes de Araujo Rana Nagarkatti Charu Gupta Ana Paula Marino Alain Debrabant 《PLoS neglected tropical diseases》2015,9(1)
Drug discovery initiatives, aimed at Chagas treatment, have been hampered by the lack of standardized drug screening protocols and the absence of simple pre-clinical assays to evaluate treatment efficacy in animal models. In this study, we used a simple Enzyme Linked Aptamer (ELA) assay to detect T. cruzi biomarker in blood and validate murine drug discovery models of Chagas disease. In two mice models, Apt-29 ELA assay demonstrated that biomarker levels were significantly higher in the infected group compared to the control group, and upon Benznidazole treatment, their levels reduced. However, biomarker levels in the infected treated group did not reduce to those seen in the non-infected treated group, with 100% of the mice above the assay cutoff, suggesting that parasitemia was reduced but cure was not achieved. The ELA assay was capable of detecting circulating biomarkers in mice infected with various strains of T. cruzi parasites. Our results showed that the ELA assay could detect residual parasitemia in treated mice by providing an overall picture of the infection in the host. They suggest that the ELA assay can be used in drug discovery applications to assess treatment efficacy in-vivo. 相似文献
67.
Ozlen Saglam Erik Samayoa Sneha Somasekar Samia Naccache Akiko Iwasaki Charles Y Chiu 《PloS one》2015,10(4)
Vulvar Intraepithelial Neoplasia (VIN) is the precursor lesion of Vulvar Squamous Cell Carcinoma (VSCC), and the differentiated type (dVIN) is more frequently observed in relation to VSCC. In contrast to usual-type VIN (uVIN), which is related to infection by human papillomavirus (HPV), a germline mutation in the p53 gene is thought to be associated with ~90% of dVIN cases. To date, no infectious agent has been identified in association with dVIN, and studies investigating this possibility have been hindered by the difficulty in accurately diagnosing dVIN from small biopsies. Here, we used immunostaining for p16ink4a, a biomarker for HPV infection, to study 14 uVIN high-grade VIN and 14 dVIN cases, and to select 10 dVIN cases to broadly screen for all known viruses using a pan-viral microarray platform (ViroChip). All of the uVIN tissue samples, including 8 warty and 6 basaloid cases, showed positivity with the p16ink4a immunostain. The staining pattern was full-thickness for all except two cases in which positive staining was localized in the lower 1/3 of the epidermis. In contrast, immunostaining for p16ink4a was negative in all dVIN cases. ViroChip analysis of 10 pure dVIN samples confirmed the absence of human papillomavirus subtypes or any other virus with the exception of a single sample that showed a weak microarray signature to a porcine herpesvirus. Follow-up PCR testing of the sample was negative for herpesvirus, and in-depth metagenomic next-generation sequencing revealed only sequences corresponding to non-pathogenic viral flora and bacterial contamination. In this study, we demonstrated lack of a virus association in 10 dVIN cases. Alternative pathways for carcinogenesis such as the p53 mutation should be considered for investigation of potential treatment options in dVIN. 相似文献
68.
Radha Vaddavalli Sneha Peddi Srilekha Yadav Kothagauni Venkateswar Rao Linga 《Antonie van Leeuwenhoek》2014,105(3):443-450
A novel actinomycete strain, designated VRC07T, was isolated from a Callistemon citrinus rhizosphere sample collected from Hyderabad, India. Its taxonomic status was determined by using polyphasic approach. It is a Gram-positive, aerobic, non-motile, weakly acid-fast strain. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain VRC07T is a member of the genus Nocardia. The highest levels of 16S rRNA gene sequence similarity was found between the strains Nocardia niwae W9241T (99.6 %), Nocardia amikacinitolerans W9988T (99.3 %) and Nocardia arthritidis IFM 10035T (98.9 %); similarity to other type strains of the genus Nocardia was below 98.7 %. The organism had chemical and morphological features consistent with its classification in the genus Nocardia such as meso-diaminopimelic acid as the diagnostic diamino acid in the cell wall peptidoglycan. Arabinose and galactose as the diagnostic sugars. Diagnostic polar lipids were phosphatidylinositol, diphosphatidylglycerol, and phosphatidylglycerol. The predominant menaquinone was MK-8(H4, ω-cycl). The major fatty acids were C16:0, C18:0, C18:1 w9c, C18:0 10-methyl TBSA and sum in feature 3 (16:1 w7c/16:1 w6c). The G+C content of the genomic DNA was 68.5 mol%. The DNA–DNA relatedness data, together with phenotypic differences clearly distinguished the isolate from its closest relatives. On the basis of these phenotypic and genotypic data, the isolate represents a novel species, for which the name Nocardia bhagyanesis sp. nov., is proposed. The type strain is VRC07T (=KCTC 29209T = MTCC 11725T = ATCC BAA-2548). 相似文献
69.
Mesenchymal stromal cells (MSCs) show promise in cell-based transplantations and regenerative medicine applications. MSCs from Wharton’s jelly (WJ) of umbilical cord can be easily harvested and exhibit greater proliferative activity than bone marrow MSCs. It is important to develop a practical cryopreservation technique to effectively store umbilical cord for potential future applications. Successful cryopreservation would allow access to umbilical cord from the same donor for repeated WJ MSC-based transplantations. For therapeutic applications, one should be able to obtain clinically-relevant quality and quantity of MSCs from cryopreserved tissues. In this study, we optimised a serum-free formulation of 10% dimethyl sulfoxide (DMSO) and 0.2 M sucrose for cryopreservation of umbilical cord tissue. Slow freezing and rapid thawing were adopted. MSCs harvested from WJ of cryopreserved umbilical cord could undergo robust expansion, differentiate to mesodermal lineages and express MSC-characteristic surface antigens. The cumulative cell yield, however, was less compared to corresponding fresh cord tissue. 相似文献
70.
Anjana Devkota Stefano Dall'Acqua Stefano Comai Gabbriella Innocenti Pramod Kumar Jha 《Biochemical Systematics and Ecology》2010
Centella asiatica (L.) Urban is widely used in traditional medicine in many countries and in the formulation of drugs and cosmetics, and is therefore suitable as a trade item for the development of medicinal plants for the population of Nepal. The aim of this work was to select plant populations of C. asiatica with high contents of secondary metabolites growing in various localities in Nepal, and to enhance knowledge of the cultivation of this plant. Quali-quantitative analysis of bioactive triterpenes (asiaticoside and asiatic acid) and phenol derivatives (flavonoids and caffeoyl esters) was performed by HPLC-DAD-ELSD. The highest quantities of triterpenes and phenols were found in samples from the Gorkha and Chitwan districts. Regarding cultivated plants, soil fertilisation is critical, since over-rich soils affect secondary metabolite content. Plants growing in sand-rich soils produce more terpenes. This work provides indications on how to select high-terpene producing germplasm and recommendations for plant cultivation. 相似文献