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91.
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93.
Cell-specific in vivo DNA-protein interactions at the proximal promoters of the pro alpha 1(I) and the pro alpha2(I) collagen genes.
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We performed in vivo dimethylsulfate footprinting of the 220 bp mouse proximal proalpha1(I) collagen promoter and the 350 bp mouse proximal proalpha2(I) collagen promoter in BALB/3T3 fibroblasts, primary mouse skin fibroblasts, S-194 B cells, NMuLi liver epithelial cells and RAG renal adenocarcinoma cells and in vitro DNase I footprinting of these promoters using nuclear extracts of these different cell types. Whereas proalpha1(I) and proalpha2(I) collagen RNAs were present in BALB/3T3 fibroblasts and primary fibroblasts, these RNAs could not be detected in the three other cell lines. Comparison of in vitro DNase I footprints for each of the two proximal collagen promoters indicated that the patterns of protection were very similar with the different nuclear extracts, suggesting that the DNA binding proteins binding to these promoters were present in all cell types tested. In contrast, in vivo footprints over these proximal promoters were cell-specific, occurring only in fibroblast cells and not in the other three cell types. The in vivo footprints were generally located within the in vitro footprinted regions. Our results suggest that although all cell types tested contained nuclear proteins that can bind to the proximal proalpha1(I) and proalpha2(I) collagen promoters in vitro , it is only in fibroblasts that these proteins bind to their cognate sites in vivo . We discuss possible regulatory mechanisms in type I collagen genes that can contribute to the cell-specific in vivo protein-DNA interactions at the proximal promoters. 相似文献
94.
Egg production features viz. weekly hen day and egg weight together with some stress markers were studied in RIR birds reared under backyard in different agroclimatic zones of West Bengal. Overall, weekly hen day average and egg weight in summer was 3.39 ± 0.09 and 45.13 ± 0.24 g, respectively. But the pattern of egg production in various zones is not same, as significant egg production difference (P ≤ 0.01) among zones was noticed in summer, from 26th to 37th week. There was significant (P ≤ 0.01) correlation between weekly hen day average and egg weight on 26th, 35th and 37th week (P ≤ 0.05). The observed overall level of antioxidant enzymes viz. SOD (U/g of Hb), glutathione peroxidase (GSH-Px) (μmol/L), TAS (mmol/L) and LDH (IU/L) were 0.56 ± 0.61, 565.15 ± 0.61, 1.43 ± 0.61 and 203.05 ± 0.61, respectively, irrespective of zones. It was observed that mean concentration of SOD, GHS-Px, TAS and LDH of RIR birds reared at backyard have positive association with weekly hen day average and average egg weight throughout summer stress. The current findings showed that RIR birds reared at backyard had better adaptation ability to summer stress in different agroclimatic zones of West Bengal. 相似文献
95.
Prajna Paramita Ray Tania Chatterjee Sraboni Roy Suvojit Rakshit Madhumita Bhowmik Jaysree Guha Aniruddha Maity Indraneel Saha Ankur Bhowal Aniruddha Chatterjee Supriti Sarkar Debabrata Nag B. R. Maiti 《Proceedings of the Zoological Society》2018,71(1):30-47
Noise is a world-wide problem that causes nervous, endocrine and cardiovascular disorders, and eventually health hazards in humans and animals. Objective of the current work is to investigate endocrine interaction in noise stress, which subsequently affects other endocrine functions including gonads in a poultry bird like chicks. Gravimetric, ultrastructural and hormonal status of the endocrine organs were examined to ascertain the effects of noise stress. Acute noise at 60 dB had no effect, but at 80 and 100 dB each for 3 h, increased pineal and serum serotonin, and adrenal and serum corticosterone, epinephrine and norepinephrine concentrations, without any change in thyroid or gonadal hormones. Chronic noise exposure at 60, 80 and 100 dB each for 6 h, daily for 7 days, drastically disturbed normal behavior, and quantum of food consumption and water intake. Chronic exposure also significantly decreased body weight including thyroid, ovary and testis weight, and increased adrenal weight. Noise stress caused ultrastructural changes leading to stimulations of pinealocytes (with abundance of rough endoplasmic reticulum and mitochondria), adrenocortical cells (enlarged nuclei and abundance of smooth endoplasmic reticulum) and adrenomedullary cells (enlarged nuclei with presence of chromaffin granules) were observed in noise stress. Additionally, pineal and serum serotonin, N-acetyl serotonin and melatonin, and adrenal and serum corticosterone, epinephrine and norepinephrine levels were significantly elevated following chronic noise exposure. Contrarily, thyroid activity was suppressed with atrophied thyroid follicles followed by declined levels of serum T3 and T4 with elevation of TSH level. Simultaneously, serum 17β-estradiol (E2) and testosterone (T) concentrations were also significantly declined in all the doses of chronic noise. These changes were dose dependent of noise exposure. The findings suggest that (a) adrenal and pineal glands respond primarily to noise and secondarily act on other endocrine organs including gonads in chicks, (b) adrenal directly and/or indirectly causes thyroid and gonadal dysfunctions via pineal following noise exposure in chicks. 相似文献
96.
Dhanabal Kumarasamy Biswajit Gopal Roy Joana Rocha-Pereira Johan Neyts Satheeshkumar Nanjappan Subhasis Maity Musfiqua Mookerjee Lieve Naesens 《Bioorganic & medicinal chemistry letters》2017,27(2):139-142
A series of 4-substituted 3,4-dihydropyrimidine-2-ones (DHPM) was synthesized, characterized by IR, 1H NMR, 13C NMR and HRMS spectra. The compounds were evaluated in vitro for their antiviral activity against a broad range of DNA and RNA viruses, along with assessment for potential cytotoxicity in diverse mammalian cell lines. Compound 4m, which possesses a long lipophilic side chain, was found to be a potent and selective inhibitor of Punta Toro virus, a member of the Bunyaviridae. For Rift Valley fever virus, which is another Bunyavirus, the activity of 4m was negligible. DHPMs with a C-4 aryl moiety bearing halogen substitution (4b, 4c and 4d) were found to be cytotoxic in MT4 cells. 相似文献
97.
The kinetics of interfacial proton transfer reaction is an important factor in proton transport across membranes. The following
experimental system was designed in order to measure this kinetics. Sonicated liposomes having the protonophore SF6847 was
suspended in Tris buffer. Application of a temperature jump (in ∼ 3 μs) caused a drop in the aqueous phase pH which was subsequently
sensed by the membrane-bound SF6847. The kinetics of this interfacial proton transfer reaction was monitored on μs timescales.
The estimated bimolecular rate constant of 2×1011 M−1 s#x2212;1 for this process show that there is no kinetic barrier for the transfer of protons from the aqueous phase to the membrane-water
interface. 相似文献
98.
Mandal S Maity KK Bhunia SK Dey B Patra S Sikdar SR Islam SS 《Carbohydrate research》2010,345(18):2657-2663
Two different glucans (PS-I, water-soluble; and PS-II, water-insoluble) were isolated from the alkaline extract of fruit bodies of an edible mushroom Calocybe indica. On the basis of acid hydrolysis, methylation analysis, periodate oxidation, and NMR analysis ((1)H, (13)C, DEPT-135, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit of these polysaccharides were established as: PS-I: →6)-β-D-Glcp-(1→6)-β-D-glcp-(1→6)-)-β-D-Glcp-(1→ α-D=Glcp (Water-soluble glucan). PS-II: →3)-β-D-Glcp-(1→3)-β-D-glcp-(1→3)-)-β-D-Glcp-(1→3)-β-D-Glcp-(1→ β-D-Glcp (Water-insoluble glucan, Calocyban). 相似文献
99.
100.
Mandal EK Maity K Maity S Gantait SK Behera B Maiti TK Sikdar SR Islam SS 《Carbohydrate research》2012,347(1):172-177
An immunostimulating water-soluble glucan was isolated from hot aqueous extract of fruit bodies of an edible mushroom Calocybe indica. Structural investigation of the glucan was carried out using acid hydrolysis, methylation analysis, and NMR studies ((1)H, (13)C, DEPT-135, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC). On the basis of above-mentioned experiments, the structure of the repeating unit of the polysaccharide was established as [see figure in text]. This glucan stimulated the splenocytes and thymocytes. 相似文献