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951.
Jyotsna Chakraborty 《Molecular reproduction and development》1979,2(1):25-34
In the course of the reorganization and degeneration of the proximal centriole in the mature acentriolate spermatozoon of the Mongolian gerbil, both the proximal and distal centrioles appear in the early cap phase of spermatid development. During the acrosome phase, both distal and proximal centrioles become highly active in the formation of a segmented column. The proximal centriole becomes actively involved in the formation of the capitulum, while the distal centriole forms the axonemal complex and dense fibers. During the maturation phase of spermatid development, the “pinwheel” arrangement of the proximal centriole becomes an “S”-shaped structure, turned 90° on its vertical axis. The few “doublet” microtubules that can be detected later in that stage completely disappear during spermiation. The distal centriolar area develops a single central pair of microtubules and membranous elements. Another prominent feature in the neck region of the gerbil spermatozoa is the presence of two dense rudimentary columns in association with the mitochondria. Although their density is similar to that of the other columns, these two columns have no connection with the dense fibers; in fact, they are closely associated with the mitochondria. 相似文献
952.
Lakshmi Devi Suzana Petanceska Roy Liu Babak Arbabha Mylarao Bansinath Uttam Garg 《Journal of neurochemistry》1994,62(6):2387-2393
Abstract: Nitric oxide (NO), a recently discovered neuro-transmitter, has been shown to have a cytostatic effect on cultured glia. A NO-generating agent, S -nitroso- N -acetyl-penicillamine (SNAP), was used to treat C6 glioma and primary cortical astrocytes. The levels of a monobasic peptide-processing enzyme activity and carboxypeptidase E activity were examined. The cellular levels of these two enzymes are specifically reduced in response to treatment with SNAP. A decrease of ˜30–50% in these two'enzyme activities was seen in both primary astrocytes and C6 glioma cells. This decrease in cellular enzyme activities is not due to increased secretion because the secreted activity is also reduced in response to SNAP treatment in both the glioma cells and the primary astrocytes. Removal of SNAP treatment causes the carboxypeptidase enzyme activity to return to control levels within 3 days. Northern and western blot analyses indicate that the reduced cellular level of carboxypeptidase E is not due to reduced expression of the messenger RNA or protein, suggesting that the SNAP treatment is affecting factors that influence carboxypeptidase E activity. Taken together, these results imply that NO is involved in the regulation of peptide biosynthetic enzymes and this could lead to the antimitogenic action of SNAP on glia. 相似文献
953.
Jyotsna Verma Santosh Pasha Sharad V. Gangal 《Molecular and cellular biochemistry》1994,131(2):157-166
A component ofFusarium solani (F. solani), identified as the major allergen,Fus sI3596
* was purified to homogeneity from culture filtrate (CF) by means of anion-exchange column chromatography, gel filtration and FPLC. The homogeneity ofFus sI3596
* was assessed by IEF, PAGE, SDS-PAGE (non-reducing), immunoblot and HPLC.Fus sI3596
* was isolated as a glycoprotein of MW 65 kd and pI 3.6. The IgE ELISA-inhibition assay after periodate treatment of the fraction showed a lower IgE binding capacity suggesting involvement of carbohydrate moiety in IgE binding reactions of the allergen. Peptide fragments ofFus sI3596
* obtained after CNBr and trypsin treatment were analysed by immunoblotting for their allergenicity. This study indicated that there could be at least 3 allergenic determinants in the major allergen,Fus sI3596
* ofF. solani CF.Abbreviations DEAE
diethyl aminoethyl
- HPLC
high performance liquid chromatography
- SDS
sodium dodecyl sulphate
- PBS-Tween
phosphate buffer saline containing 0.1% tween
- DTT
dithiothreitol
- TFA
triflouroacetate
- FPLC
fast protein liquid chromatography 相似文献
954.
The pattern of photorespiratory ammonia (PR–NH3) formation and its modulation by exogenous bicarbonate or glycine were investigated in C3–C4 intermediates of Alternanthera (A. ficoides and A. tenella) and Parthenium hysterophorus in comparison to those of C3 or C4 species. The average rates of PR–NH3 accumulation in leaves of the intermediates were slightly less than (about 25% reduced) those in C3 species, and were further low in C4 plants (40% of that in C3). The levels of PR–NH3 in leaf discs decreased markedly when exogenous bicarbonate was present in the incubation medium. The inhibitory effect of bicarbonate on PR–NH3 accumulation was pronounced in C3 plants, very low in C4 species and was moderate in the C3–C4 intermediates. Glycine, an intermediate of photorespiratory metabolism, raised the levels of PR–NH3 in leaves of not only C4 but also C3–C4 intermediates, bringing the rates close to those of C3 species. The rate of mitochondrial glycine decarboxylation in darkness in C3–C4 intermediates was partially reduced (about 80% of that in C3 species), corresponding to the activity-levels of glycine decarboxylase and serine hydroxymethyltransferase in leaves. The intermediates had a remarkable capacity of reassimilating photorespiratory CO2 in vivo, as indicated by the apparent refixation of about 85% of the CO2 released from exogenous glycine in the light. We suggest that the reduced photorespiration in the C3–C4 intermediate species of Alternanthera and Parthenium is due to both a limitation in the extent of glycine production/decarboxylation and an efficient refixation/recycling of internal CO2.Abbreviations GDC
glycine decarboxylase
- GS
glutamine synthetase
- GOGAT
glutamate-oxoglutarate aminotransferase
- -HPMS
-hydroxy-2-pyridinemethanesulfonic acid
- INH
isonicotinyl hydrazide
- MSO
L-methionine sulfoximine
- PR–NH3
photorespiratory-ammonia
- SHMT
serine hydroxymethyltransferase 相似文献
955.
Identification of the regeneration potential of embryo derived calluses from various Indica rice varieties 总被引:3,自引:0,他引:3
Seraj Zeba I. Islam Zahidul Faruque M. Omar Devi Tripti Ahmed Salma 《Plant Cell, Tissue and Organ Culture》1997,48(1):9-13
The regeneration response of mature and immature rice embryos from 15 rice varieties (Oryza sativa L. var. indica) was separately measured in terms of regeneration per cent and total number of regenerated plantlets obtained for a fixed sample size per variety, when cultured on standard MS media. The response of the rice varieties was classed as high, medium or poor, based on the above criteria. The regeneration per cent of genotypes showing high, medium and poor response ranged from 67 to 97, 38 to 63 and 0 to 36 respectively. The variation in the regeneration response amongst the defined groups was found to be statistically significant in terms of regeneration per cent and total plantlets for a constant sample size when subjected to one way analysis of variance and Duncan's multiple range test. Only small influences on regeneration frequency were found when the most and least responsive genotypes, Binnatoa and BR-23 were cultured on N6 and MS media with additional or different supplements. 相似文献
956.
D. Rama Devi 《Plant Systematics and Evolution》1991,177(3-4):161-164
The floral anatomy of threeHypseocharis spp. has been studied. The genus resemblesOxalidaceae as well asMonsonia andSarcocaulon of theGeraniaceae. As it is closer toGeraniaceae than toOxalidaceae, it perhaps serves as a connecting link between them. 相似文献
957.
All the postembryonic developmental instars of Neodiaptomus lindbergi Brehm, 1953, reared in the laboratory from eggs, are described and illustrated. Further, the larval affinities of this species vis-a-vis certain other Indian diaptomid species are mentioned. 相似文献
958.
R. B. Singh S. S. Rastogi U. V. Mani Jolly Seth Laxmi Devi 《Biological trace element research》1991,30(1):59-64
In a randomized, single-blind, controlled study (400 patients aged 25-63 yr; 374 males, 26 females), 206 subjects were administered a magnesium-rich diet, and 194 subjects their usual diet, for 6 wk. Age, sex, body weight, hypertension, hyperlipidemia, smoking, obesity, diuretic therapy, and diabetes were comparable between the two groups, as were laboratory data at entry to the study. Intervention-group A received a significantly higher amount of dietary magnesium and potassium compared to group B, which received its usual diet. After 6 wk, there was a significant fall in total serum cholesterol (228.5 +/- 46.2 mg/dL), LDL cholesterol 146.5 +/- 75.5 mg/dL), and triglyceride (143.8 +/- 40.5 mg/dL) in group A compared to serum cholesterol (242.5 +/- 58.2 mg/dL), LDL cholesterol (157.0 +/- 78.4 mg/dL), and triglyceride (156.5 +/- 60.0 mg/dL) at entry to study, but no such changes in group-B subjects. HDL cholesterol showed a marginal mean decrease of 0.8 mg/dL in group B and a 2.5 mg/dL increase in group A. The changes in blood lipids were consistent with an increased intake of magnesium and with a rise in serum levels. Although a general blood-lipid-reducing effect of such a diet cannot be excluded, it is possible that dietary magnesium may have contributed to the reduction of total serum cholesterol, LDL cholesterol, and triglyceride, and the marginal rise in HDL cholesterol. More studies with longer follow-up periods are needed to confirm this observation. 相似文献
959.
Orientin (Ot) and Vicenin (Vc), two water-soluble flavonoids isolated from the leaves of Indian holy basil Ocimum sanctum have shown significant protection against radiation lethality and chromosomal aberrations in vivo. In the present study the protective effect of Ot and Vc against radiation induced chromosome damage in cultured human peripheral lymphocytes was determined by micronucleus test. In order to select the most effective drug concentration, fresh whole blood was exposed to 4Gy of cobalt-60 gamma-radiation with or without a 30 min pre-treatment with 6.25, 12.5, 15.0, 17.5 or 20 microM of Ot/Vc. Micronucleus (MN) assay was done by cytochalasin induced cytokinesis block method. Radiation significantly increased the MN frequency (16 times normal). Pre-treatment with either Ot or Vc at all concentrations significantly (P<0.05-0.001) reduced the MN count in a concentration dependent manner, with the optimum effect at 17.5 microM. Therefore, fresh blood samples were incubated with/without 17.5 microM Ot/Vc for 30 min and then exposed to 0.5-4Gy of gamma-radiation. Radiation increased the MN frequency linearly (r(2)=0.99) with dose. Pre-treatment with Ot or Vc significantly (P<0.01-0.001) reduced the MN counts to 51-67% of RT alone values, giving DMFs of 2.62 (Ot) and 2.48 (Vc). Both the compounds showed significant antioxidant activity in vitro at the above concentrations, which was significantly higher than that of DMSO at equimolar concentrations. Thus, the results demonstrate that both the flavonoids give significant protection to the human lymphocytes against the clastogenic effect of radiation at low, non-toxic concentrations. The radioprotection seems to be associated with their antioxidant activity. The clinical potential of these protectors in cancer therapy needs to be investigated. 相似文献
960.
Nikhil Sharma Namita Srivastava Bharti Devi Lokender Kumar Rajnish Kumar Ashok Kumar Yadav 《化学与生物多样性》2023,20(3):e202201191
The effectiveness of treating bacterial infections is seriously threatened by the emergence of bacterial resistance to chemical treatment. Growth of microbes in biofilm is one of the main causes of resistance to antimicrobial drugs. Quorum sensing (QS) inhibition, which targets the QS signalling system by obstructing cell-cell communication, was developed as an alternative treatment by creating innovative anti-biofilm drugs. Therefore, the goal of this study is to develop novel antimicrobial drugs that are effective against Pseudomonas aeruginosa by inhibiting QS and acting as anti-biofilm agents. In this study, N-(2- and 3-pyridinyl)benzamide derivatives were selected to design and syntheses. Antibiofilm activity was revealed by all the synthesized compounds and the biofilm was visibly impaired, and the OD595nm readings of solubilized biofilm cells presented a momentous difference between the treated and untreated biofilms. The best anti-QS zone was observed for compound 5d and found to be 4.96 mm. Through in silico research, the physicochemical characteristics and binding manner of these produced compounds were examined. For the purpose of understanding the stability of the protein and ligand complex, molecular dynamic simulation was also carried out. The overall findings showed that N-(2- and 3-pyridinyl)benzamide derivatives could be the key to creating effective newer anti-quorum sensing drugs that are effective against different bacteria. 相似文献