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1.
DefattedMadhuca butyraceae seeds contain 24% of crude protein and 10.4% of saponins. The solubility ofMadhuca seed proteins was determined in water and NaCl as a function of pH and minimum solubility occurred at pH 4.0. The proteins
consist of three components with S20,w values of 2.2, 9.8 and 15.4. On gel filtration the proteins gave three peaks and on diethylaminoethyl cellulose chromatography
they resolved into two components. Thein vitro digestibility ofMadhuca seed protein was found to be 69% when assayed with a pepsin-pancreatin system. 相似文献
2.
Summary Two varieties of tomato (Pusa Rubi and Selection 120) positively responded to algal inoculation in terms of the yield of fruits and shoots, but there was no significant effect on the vitamin C content of the fruits. A combined application of urea and algae was more effective than the application of urea alone. 相似文献
3.
Venkataraman Amarnath Traci L. Miller Arthur D. Broom 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1983,741(2):224-229
Poly(5-fluoro-2′-deoxyuridylic acid) was synthesized and its properties were compared with those of poly(dT) and poly(dU). It readily complexed with poly(dA). The 1:1 complex melted at about 20°C lower than poly(dA) · poly(dT). A triple-stranded helix, poly(dA)·2 poly(dF5U) was formed only in high salt (2.0 M NaCl). 相似文献
4.
The effects of radiation on the kinetics of Interleukin-2 (IL-2) production and utilization by mononuclear cells (MNCs) were studied. Mononuclear cells from normal, healthy individuals were subjected to various doses of radiation ranging from 0 to 2,000 rad and cultured in the presence of PHA. Supernatants from these cultures were harvested at various periods and their IL-2 contents determined by both the standard bioassay and ELISA. A radiation dose of 800 rad and higher had a marked effect on both IL-2 production and consumption. Although the supernatants from both the irradiated and non-irradiated MNCs contained maximal concentrations of IL-2 between 8 and 24 h of culture, the former had three times as much IL-2 as the latter. An increase in IL-2-mRNA levels was also noticed in irradiated, PHA-stimulated cells. Moreover, the supernatants from irradiated MNCs collected as late as 72 h after the initiation of culture contained more than 30% of the total IL-2 produced compared to less than 8% in supernatants from non-irradiated cells. Supernatants from non-irradiated cells incubated further with irradiated cells contained relatively higher quantities of IL-2 than those incubated continuously with non-irradiated cells. Supernatants from co-cultures of irradiated and non-irradiated MNCs contained less than expected amounts of IL-2 in two of the three subjects. Despite a difference in both the production and consumption of IL-2 between the irradiated and non-irradiated cells, there was no difference in their ability to generate IL-2 receptors. The results indicate that inactivation of radiosensitive suppressor T cells is associated with superinduction of IL-2 mRNA, increased production and decreased consumption of IL-2 by MNCs, thereby resulting in increased accumulation of IL-2. 相似文献
5.
Michael D. Reily Venkataraman Thanabal Michael E. Adams 《Journal of biomolecular NMR》1995,5(2):122-132
Summary The 48 amino acid peptides -Aga-IVA and -Aga-IVB are the first agents known to specifically block P-type calcium channels in mammalian brain, thus complementing the existing suite of pharmacological tools used for characterizing calcium channels. These peptides provide a new set of probes for studies aimed at elucidating the structural basis underlying the subtype specificity of calcium channel antagonists. We used 288 NMR-derived constraints in a protocol combining distance geometry and molecular dynamics employing the program DGII, followed by energy minimization with Discover to derive the three-dimensional structure of -Aga-IVB. The toxin consists of a well-defined core region, comprising seven solvent-shielded residues and a well-defined triple-stranded -sheet. Four loop regions have average backbone rms deviations between 0.38 and 1.31 Å, two of which are well-defined type-II -turns. Other structural features include disordered C- and N-termini and several conserved basic amino acids that are clustered on one face of the molecule. The reported structure suggests a possible surface for interaction with the channel. This surface contains amino acids that are identical to those of another known P-type calcium channel antagonist, -Aga-IVA, and is rich in basic residues that may have a role in binding to the anionic sites in the extracellular regions of the calcium channel.Abbreviations TOCSY
total correlated spectroscopy
- NOESY
nuclear Overhauser enhancement spectroscopy
- COSY
correlated spectroscopy 相似文献
6.
Venkataraman Amarnath Traci L. Miller Arthur D. Broom 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,800(3):207-213
The synthesis of a high-molecular-weight, putatively all-syn DNA analogue, poly(8-bromo-2′-deoxyadenylic acid), is described. The syn → anti transition was shown to be both salt and temperature dependent. Conditions were found which favored ‘normal’ Watson-Crick pairing and duplex formation with poly(dT). 相似文献
7.
Saponins, isolated from M. butyracea, were assessed for their acute and subacute oral toxicity in albino rats. Acute doses of saponins caused mortalities and LD50 and LD90 values were 330 and 430 mg/kg body wt respectively. Severe diarrhoea, restlessness and histopathological changes were observed in liver and kidney. Diets containing saponins at 0,250,500 and 1000 ppm for 14 weeks did not affect food intake, growth or organ weights, but induced mild histological changes in liver and kidney and altered the serum levels of alkaline phosphatase, blood urea nitrogen, cholesterol and proteins, particularly in female rats. 相似文献
8.
Studies were carried out to determine the effects of cryopreservation on the mitogen-induced proliferative and immunoglobulin-producing abilities of peripheral blood mononuclear cells (MNC) of patients with lung cancer and normal controls. One-half of each sample of cells was tested fresh, while the other half was frozen, thawed immediately, and cultured at the same time. The responses of each sample of cryopreserved cells were compared to the responses of fresh cells from the same individual in simultaneous assays. The cryopreserved mononuclear cells of most of the lung cancer patients showed significantly enhanced plaque-forming cell (PFC) responses after stimulation with pokeweed mitogen (PWM). No such significant differences were observed between the proliferative responses of cryopreserved and fresh cells against phytohemagglutinin (PHA) or PWM stimulation. The cryopreserved MNC of some of the normal controls also showed a similar increase in the PFC responses, although to a lesser extent. Coculture of cryopreserved B cell-enriched populations of cells with fresh T cell-enriched fractions obtained from these patients also resulted in the generation of a higher number of PFCs as compared to the number of PFCs observed after coculture of fresh B and T cell-enriched populations. The results indicate that the suppressor activities of monocytes/macrophages and other non-T cells (NK cells) are sensitive to cryopreservation. The results also show that the MNC of patients with lung cancer can be cryopreserved and used for subsequent B and T cell assays. 相似文献
9.
Topological constraints in nucleic acid hybridization kinetics 总被引:2,自引:0,他引:2
Bois JS Venkataraman S Choi HM Spakowitz AJ Wang ZG Pierce NA 《Nucleic acids research》2005,33(13):4090-4095
A theoretical examination of kinetic mechanisms for forming knots and links in nucleic acid structures suggests that molecules involving base pairs between loops are likely to become topologically trapped in persistent frustrated states through the mechanism of ‘helix-driven wrapping’. Augmentation of the state space to include both secondary structure and topology in describing the free energy landscape illustrates the potential for topological effects to influence the kinetics and function of nucleic acid strands. An experimental study of metastable complementary ‘kissing hairpins’ demonstrates that the topological constraint of zero linking number between the loops effectively prevents conversion to the minimum free energy helical state. Introduction of short catalyst strands that break the topological constraint causes rapid conversion to full duplex. 相似文献
10.
Ernst S Garro OA Winkler S Venkataraman G Langer R Cooney CL Sasisekharan R 《Biotechnology and bioengineering》1997,53(6):575-582
Heparinase I from flavobacterium heparinum has several potential clinical applications; the resulting high demands on protein purity and quantity can be met by recombinant expression in Escherichia coli. Based on laboratory scale experiments with insoluble heparinase I expression followed by renaturation, a process for production of 3 kg/year of heparinase I was designed. We present a comparative analysis of the production costs of soluble and insoluble heparinase I expression, as well as a generalized approach to sensitivity analysis, based on perturbation around a base case design scenario. This may assist focusing further development on process steps for which improvements both are feasible and result in significant cost saving. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 53: 575-582, 1997. 相似文献