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11.
Effect of Maternal Alcohol Consumption on the Lipid Composition of CNS in the Offspring 总被引:1,自引:0,他引:1
T. Lalitha Krishna Kumar C. V. Ramakrishnan S. D. Telang 《Journal of neurochemistry》1988,50(5):1346-1351
Maternal alcohol consumption at a level that does not affect calorie intake increases cholesterol concentration and content as well as incorporation of labeled glucose into cholesterol in the brain and spinal cord of newborn rat pups. Continued consumption of alcohol during lactation also affects the galactolipid concentration in the brain and spinal cord of pups at 21 days of age, and this increase seems mainly to be due to an increase in content of myelin lipids. Analysis of myelin shows that the concentration of phospholipids also increases in this fraction. The increase in incorporation of labeled glucose into these membrane lipids suggests an increase in the synthesis of these lipids, which prevents fluidization of the membrane by alcohol. That in the brainstem the increase in levels of cholesterol and galactolipids is higher than in other regions and that there is also an increase in content of sphingomyelin, phosphatidylcholine, and phosphatidylethanolamine suggest that the brainstem needs better protection against fluidization. 相似文献
12.
This study was designed to obtain sister-chromatid exchange (SCE) frequencies in bone marrow and spleen cells of mice and Chinese hamsters under in vivo and in vivo/in vitro systems following treatment of animals with varying doses (15-405 micrograms/kg) of triethylenemelamine (TEM). A dose-related SCE response was found in both species, tissues, and systems analyzed following TEM treatment. In vivo, similar responses were noted for both tissues in both species. However, in vivo/in vitro, the response was lower than in vivo and it varied with the tissue. The spleen cells were more sensitive and gave higher numbers of SCEs than bone marrow of both species at the two highest doses tested (135 and 405 micrograms/kg). These differences may be attributed to cell-culturing effects, type of cells analyzed, species and tissue specificities, and pharmacokinetic properties of the chemical. This study lends support to recently established in vivo/in vitro cell culture methodologies employing mice and Chinese hamsters for comparative cytogenetic analysis. 相似文献
13.
Yolk proteins from nematodes, chickens, and frogs bind strongly and preferentially to left-handed Z-DNA 总被引:4,自引:0,他引:4
P Krishna B P Kennedy J H van de Sande J D McGhee 《The Journal of biological chemistry》1988,263(35):19066-19070
Yolk proteins purified from the nematode Caenorhabditis elegans, from the frog Xenopus laevis, and from chicken eggs all have the unexpected property of binding strongly and preferentially to a left-handed Z-DNA probe, brominated poly(dG-dC). We estimate that the nematode proteins bind to Z-DNA with an association constant of at least 10(4) (M-1) and that this association constant is at least 40-50-fold higher than the association constant to B-DNA. Thus, yolk proteins have a higher Z-DNA specificity than most of the Z-DNA binding proteins previously isolated from other sources. Although yolk protein binding to Z-DNA is poorly competed by a wide variety of nucleic acids, the interaction is strongly competed by the phospholipids cardiolipin and phosphatidic acid (500-1000-fold better than by the same mass of B-DNA). We suggest that Z-DNA interacts with the yolk protein phospholipid binding site. In general, our results emphasize the danger of using physical properties to infer biological function. In particular, our results should raise serious questions about the biological relevance of previously isolated Z-DNA binding proteins. 相似文献
14.
The anatomical distribution of FMRFamide-like immunoreactivity in the forebrain and pituitary of the catfish, Clarias batrachus, was investigated. Immunoreactive cells were observed in the ganglion cells of the nervus terminalis (NT) and in the medial olfactory tracts. In the preoptic area, FMRFamide-containing perikarya were restricted to the lateral preoptic area, paraventricular subdivision of the nucleus preopticus, nucleus suprachiasmaticus and nucleus preopticus periventricularis posterior. In the postoptic area, some cells of the nucleus postopticus lateralis and nucleus of the horizontal commissure showed moderate immunoreactivity. In the tuberal area, immunoreactivity was observed in few cells of the nucleus hypothalamicus ventralis and nucleus arcuatus hypothalamicus (NAH). Nucleus ventromedialis thalami was the only thalamic nucleus with FMRFamide immunoreactivity. Immunoreactive processes were traceable from the NT through the medial as well as lateral olfactory tracts into the telencephalon and the area ventralis telencephali pars supracommissuralis (Vs). Further caudally, the immunoreactive fibers could be traced into discrete areas, including habenular and posterior commissures, neurohypophysis and pituitary; isolated fibers were also observed in the pineal stalk. A loose network of immunoreactive processes was observed in the olfactory bulbs and the entire telencephalon, with higher densities in some areas, including Vs. A dense plexus of immunoreactive fibers was seen in the pre- and postoptic areas and around the paraventricular organ, while relatively few were observed in the thalamus. A high concentration of fiber terminals was found in the caudal tuberal area. 相似文献
15.
The stable free radical Tempol (4-hydroxy-2,2,6,6-tetramethyl-piperidinyloxy) has been shown to protect against X-ray-induced cytotoxicity and hydrogen peroxide- or xanthine oxidase-induced cytotoxicity and mutagenicity. The ability of Tempol to protect against X-ray- or neocarzinostatin (NCS)-induced mutagenicity or DNA double-strand breaks (dsb) was studied in Chinese hamster cells. Tempol (50 mM) provided a protection factor of 2.7 against X-ray-induced mutagenicity in Chinese hamster ovary (CHO) AS52 cells, with a protection factor against cytotoxicity of 3.5. Using the field inversion gel electrophoresis technique of measuring DNA dsb, 50 mM Tempol provides a threefold reduction in DNA damage at an X-ray dose of 40 Gy. For NCS-induced damage, Tempol increased survival from 9% to 80% at 60 ng/mL NCS and reduced mutation induction by a factor of approximately 3. DNA dsb were reduced by a factor of approximately 7 at 500 ng/mL NCS. Tempol is representative of a class of stable nitroxide free radical compounds that have superoxide dismutase-mimetic activity, can oxidize metal ions such as ferrous iron that are complexed to DNA, and may also detoxify radiation-induced organoperoxide radicals by competitive scvenging. The NCS chromophore is reduced by sulfhydryls to an active form. Electron spin resonance (ESR) spectroscopy shows that 2-mercaptoethanol-activated NCS reacts with Tempol 3.5 times faster than does unactivated NCS. Thus, Tempol appears to inactivate the NCS chromophore before a substantial amount of DNA damage occurs. 相似文献
16.
Summary The influence of trace elements (Co2+, Ni2+ and Fe3+) in varying concentrations and combination, was studied in 1.5 m3 Khadi & Village Industries Commission (KVIC) digesters for biogas generation from mangopeel. Addition of these trace metals enhanced the biogas yield and methane content moderately, the maximum being with the iron fed digester. The digesters were always found to be stable without much variation in total volatile fatty acids (VFA), pH, total alkalinity and other parameters. A methane content of 62% and biogas yield of 0.49 m3/kg VS added was obtained with 4000 mg/L FeCl3 supplemented mangopeel fed digester as compared to control having biogas yield of 0.22 m3/kg VS added with a methane content of about 48–50%. 相似文献
17.
We surveyed genetic polymorphism by two-dimensional gel electrophoresis of male reproductive tract proteins in 20 isofemale lines each ofDrosophila melanogaster andDrosophila simulans. After classifying 244 such proteins ofDrosophila melanogaster and 271 ofDrosophila simulans by their distribution between testes and accessory glands within the reproductive tract, significant correlations were found between genetic polymorphism and tissue distribution. In both species, gland-specific proteins were significantly more polymorphic than testis-specific proteins, as well as those found in both testes and glands. Simultaneously, inDrosophila simulans, proteins found in roughly equivalent relative abundance in both testes and glands were significantly less variable than gland-specific and testis-specific proteins, as well as those with a quantitative difference in relative abundance between testes and glands. These correlations may reflect general differences in variability between extracellular and intracellular proteins and between proteins with broad as opposed to tissue-specific distributions.We thank the Natural Sciences and Engineering Research Council of Canada for financial support (Grant A0235 to R.S.S.). 相似文献
18.
Stomatal Movement and Sucrose Uptake by Guard Cell Protoplasts of Commelina benghalensis L. 总被引:2,自引:0,他引:2
Sucrose concentration in guard cells of epidermal strips ofCommelina benghalensis increased with stomatal opening. Sucroseuptake patterns were investigated using guard cell protoplastsof C. benghalensis. Sucrose (0.5 mM) uptake into these protoplastswas sensitive to pH, with an optimum at pH 6. Uptake of sucroseinto guard cell protoplasts was inhibited by 2,4-dinitrophenol(DNP), diethylstilbestrol (DES) and (ptrifluoromethoxy)carbonylcyanide phenylhydrozone (FCCP), while DCMU and o-phenanthrolinehad no effect on the uptake of sucrose. Fusicoccin (FC) stimulatedsucrose influx. The influence of pH and the effect of the metabolicinhibitors on the sucrose uptake into the guard cell protoplastsare consistent with an energy dependent membrane-function. (Received July 7, 1986; Accepted September 26, 1986) 相似文献
19.
Malathi Chari K. Gupta T. G. Prasad K. S. Krishna Sastry M. Udaya Kumar 《Plant and Soil》1986,91(1):109-114
Summary The effect of calcium in the water relations and tolerance to moisture deficits was tested in groundnut and cowpea. In both species, enrichment of tissue with calcium resulted in maintenance of a higher water status under stress associated with low proline accumulation. The extent of membrane damage (as reflected by the absorbance at 273 nm) was lesser in leaves of plants fed with higher levels of Ca++ when subjected to simulated stress. The rate of water loss from the leaves of Ca++-enriched plants was also lower. The possible role of Ca++ in inducing membrane stability and maintenance of higher water status is discussed. 相似文献
20.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons. 相似文献