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101.
Hypersaline soil and pond water samples were mixed with 3?% crude oil, some samples were autoclaved to serve as sterile controls; experimental samples were not sterilized. After 6-week incubation at 40?°C under light/dark cycles, the soil microflora consumed 66?%, and after 4?weeks the pond water microflora consumed 63?% of the crude oil. Soil samples treated with 3?% casaminoacids lost 89?% of their oil after 6?weeks and water samples lost 86?% after 4?weeks. Samples treated with casaminoacids and antibiotics that selectively inhibited bacteria, lost even more oil, up to 94?%. Soil-water mixtures incubated under continuous illumination lost double as much more oil than samples incubated in the dark. The soil-water mixture at time zero contained 1.3?×?10(4) CFU?g(-1) of hydrocarbon-utilizing microorganisms which were affiliated to Halomonas aquamarina, Exiguobacterium aurantiacum, Haloferax sp., Salinococcus sp., Marinococcus sp. and Halomonas sp. After 6-week incubation with oil, these numbers were 8.7?×?10(7?)CFU?g(-1) and the Haloferax sp. proportion in the total microflora increased from 20 to 93?%. Experiments using the individual cultures and three other haloarchaea isolated earlier from the same site confirmed that casaminoacids and light enhanced their oil consumption potential in batch cultures. 相似文献
102.
103.
Contrasting patterns of variation in MHC loci in the Alpine newt 总被引:1,自引:1,他引:0
Major histocompatibility complex (MHC) genes are essential in pathogen recognition and triggering an adaptive immune response. Although they are the most polymorphic genes in vertebrates, very little information on MHC variation and patterns of evolution are available for amphibians, a group known to be declining rapidly worldwide. As infectious diseases are invoked in the declines, information on MHC variation should contribute to devising appropriate conservation strategies. In this study, we examined MHC variation in 149 Alpine newts ( Mesotriton alpestris ) from three allopatric population groups in Poland at the northeastern margin of the distribution of this species. The genetic distinctiveness of the population groups has previously been shown by studies of skin graft rejection, allozymes and microsatellites. Two putative expressed MHC II loci with contrasting levels of variation and clear evidence of gene conversion/recombination between them were detected. The Meal-DAB locus is highly polymorphic (37 alleles), and shows evidence of historical positive selection for amino acid replacements and substantial geographical differentiation in allelic richness. On the contrary, the Meal-DBB locus exhibits low polymorphism (three alleles differing by up to two synonymous substitutions) and a uniform distribution of three alleles among geographical regions. The uniform frequencies of the presumptively neutral Meal-DBB alleles may be explained by linkage to Meal-DAB . We found differences in allelic richness in Meal-DAB between regions, consistent with the hypothesis that genetic drift prevails with increasing distance from glacial refugia. Pseudogene loci appear to have evolved neutrally. The level of DAB variation correlated with variation in microsatellite loci, implying that selection and drift interplayed to produce the pattern of MHC variation observed in marginal populations of the Alpine newt. 相似文献
104.
Ibrahim H. Eissa Radwan El-Haggar Mohammed A. Dahab Marwa F. Ahmed Hazem A. Mahdy Reem I. Alsantali Alaa Elwan Nicolas Masurier Samar S. Fatahala 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1587
A novel series of 2-thioacetamide linked benzoxazole-benzamide conjugates 1–15 was designed as potential inhibitors of the vascular endothelial growth factor receptor-2 (VEGFR-2). The prepared compounds were evaluated for their potential antitumor activity and their corresponding selective cytotoxicity was estimated using normal human fibroblast (WI-38) cells. Compounds 1, 9–12 and 15 showed good selectivity and displayed excellent cytotoxic activity against both HCT-116 and MCF-7 cancer cell lines compared to sorafenib, used as a reference compound. Furthermore, compounds 1 and 11 showed potent VEGFR-2 inhibitory activity. The cell cycle progression assay showed that 1 and 11 induced cell cycle arrest at G2/M phase, with a concomitant increase in the pre-G1 cell population. Further pharmacological studies showed that 1 and 11 induced apoptosis and inhibited the expression of the anti-apoptotic Bcl-2 and Bcl-xL proteins in both cell lines. Therefore, compounds 1 and 11 might serve as promising candidates for future anticancer therapy development. 相似文献
105.
High-temperature hydrocarbon degradation by Bacillus stearothermophilus from oil-polluted Kuwaiti desert 总被引:1,自引:0,他引:1
N. A. Sorkhoh A. S. Ibrahim M. A. Ghannoum S. S. Radwan 《Applied microbiology and biotechnology》1993,39(1):123-126
Kuwaiti desert samples contaminated with crude oil contained Bacillus stearothermophilus strains capable of growth on crude oil as a sole source of carbon and energy, obligately at high temperature. No thermophilic oil utilizers were present in water samples collected from the Arabian Gulf. Most of the desert strains had an optimum temperature of 60°C and grew best on pentadecane (C15), hexadecane (C16) and heptadecane (C17). n-Alkanes with shorter and longer chains, n-alkenes, and aromatic hydrocarbons were less readily utilized.
Correspondence to: N. A. Sorkhoh 相似文献
106.
A l M usallam , A.A. & R adwan , S.S. 1990. Wool-colonizing micro-organisms capable of utilizing wool-lipids and fatty acids as sole sources of carbon and energy. Journal of Applied Bacteriology 69 , 806–813.
Two keratinolytic fungi, Chrysosporium keratinophilum and Malbranchea anamorph of Uncinocarpus reesii , and another three wool-colonizing fungi not previously reported to be keratinolytic, Aspergillus fumigatus, A. flavus and Scopulariopsis Candida , were isolated from soil samples baited with animal wool. These fungi were tested for their ability to utilize wool-lipids as sole source of carbon and energy. The lipid contents of wool of various animals ranged between 2 and 5%. The different lipid extracts were similar in composition; they contained steryl esters, sterols, fatty acids, fatty alcohols and monoacylglycerols. The predominant acyl moiety in wool-lipids of different animals was linolenic acid (18:2). The five fungi tested grew well on an inorganic medium supplemented with total wool-lipids as sole sources of carbon and energy. Individual lipid classes fractionated by preparative thin layer chromatography and suspended into inorganic medium were able to support fungal growth as sole carbon sources. These fungi and another eight wool-colonizing strains. C. tropicum, C. zonatum, C . anamorph of Arthroderma curryei, Microsporum cams, M. distortum, Trichophyton interdigitale, Emmonsia parva and Myceliophthora vellerae could also utilize standard lipids and fatty acids (cholesterol and palmitic and linoleic acids)- Evidence for the uptake and degradation of chloesterol by C. keratmophilum is presented. 相似文献
Two keratinolytic fungi, Chrysosporium keratinophilum and Malbranchea anamorph of Uncinocarpus reesii , and another three wool-colonizing fungi not previously reported to be keratinolytic, Aspergillus fumigatus, A. flavus and Scopulariopsis Candida , were isolated from soil samples baited with animal wool. These fungi were tested for their ability to utilize wool-lipids as sole source of carbon and energy. The lipid contents of wool of various animals ranged between 2 and 5%. The different lipid extracts were similar in composition; they contained steryl esters, sterols, fatty acids, fatty alcohols and monoacylglycerols. The predominant acyl moiety in wool-lipids of different animals was linolenic acid (18:2). The five fungi tested grew well on an inorganic medium supplemented with total wool-lipids as sole sources of carbon and energy. Individual lipid classes fractionated by preparative thin layer chromatography and suspended into inorganic medium were able to support fungal growth as sole carbon sources. These fungi and another eight wool-colonizing strains. C. tropicum, C. zonatum, C . anamorph of Arthroderma curryei, Microsporum cams, M. distortum, Trichophyton interdigitale, Emmonsia parva and Myceliophthora vellerae could also utilize standard lipids and fatty acids (cholesterol and palmitic and linoleic acids)- Evidence for the uptake and degradation of chloesterol by C. keratmophilum is presented. 相似文献
107.
Lipids from callus cultures and suspension cultures of higher plants constitute 5 to 8% of the dry tissue's weight.The predominant lipid classes are the sterols, steryl esters, steryl glycosides and esterified steryl glycosides. Considerable amounts of a variety of sterylglycolipids, whose structures are not completely elucidated, are also present. Triglycerides and phospholipids occur in small proportions, whereas monogalactosyl diglycerides, digalactosyl diglycerides and sulfoquinovosyl diglycerides are present only in traces, if at all.β-Sitosterol is the predominant constituent sterol, stigmasterol and campesterol as well as a variety of as yet unidentified sterols occur in smaller proportions. The major constituent fatty acids are palmitic, oleic, linoleic and linolenic acids. Saturated very long-chain fatty acids are found in smaller proportions. Unusual fatty acids, such as epoxy acids, which occur in the seed lipids of certain plants, are not found in tissue cultures derived from these plants. Clucose and traces of galactose are the only sugars obtained by acid hydrolysis of the glycolipids occurring in plant tissue cultures. 相似文献
108.
S.S. Radwan Sylvia Grosse-Oetringhaus H.K. Mangold 《Chemistry and physics of lipids》1978,22(3):177-184
The lipid contents of callus cultures of rape (Brassica napus) and nasturtium (Tropaeolum majus) increase in response to decreasing the temperature, though to different degree. Irrespective of the incubation temperature the lipids in cultures of both plants contain as predominant classes steryl glycosides, esterified steryl glycosides, sterols, steryl esters and fatty acids and, as minor constituents, various proportions of triacylglycerols, phospholipids and several unidentified fractions.The ratio of phospholipids to triacylglycerols as well as the ratio of diacylglycerophosphorylethanolamines to dicylglycerophosphorylcholines increase with time both in rape cultures incubated at 30°C and in those kept at 5°C.The lipids in rape and nasturtium cultures grown at 30°C contain smaller proportions of polyunsaturated fatty acids than the lipids in cultures incubated at 5°C. Erucic acid, the major constituent fatty acid of the seed lipids, in both plants, occurs only in trace amounts in the lipids of callus cultures. In contrast, linoleic and linolenic acids, which occur only in traces in the seed lipids of nasturtium, are major constituent fatty acids in the lipids of callus cultures derived from seedlings of this plant.The levels of constituent polyunsaturated fatty acids in the diacylglycerophosphorylethanolamines and the diacylglycerophosphorylcholines increase with time whereas in the triacylglycerols only linolenic acid is slightly increased. 相似文献
109.
Secondary heart field contributes myocardium and smooth muscle to the arterial pole of the developing heart 总被引:13,自引:0,他引:13
Waldo KL Hutson MR Ward CC Zdanowicz M Stadt HA Kumiski D Abu-Issa R Kirby ML 《Developmental biology》2005,281(1):78-90
The arterial pole of the heart is the region where the ventricular myocardium continues as the vascular smooth muscle tunics of the aorta and pulmonary trunk. It has been shown that the arterial pole myocardium derives from the secondary heart field and the smooth muscle tunic of the aorta and pulmonary trunk derives from neural crest. However, this neural crest-derived smooth muscle does not extend to the arterial pole myocardium leaving a region at the base of the aorta and pulmonary trunk that is invested by vascular smooth muscle of unknown origin. Using tissue marking and vascular smooth muscle markers, we show that the secondary heart field, in addition to providing myocardium to the cardiac outflow tract, also generates prospective smooth muscle that forms the proximal walls of the aorta and pulmonary trunk. As a result, there are two seams in the arterial pole: first, the myocardial junction with secondary heart field-derived smooth muscle; second, the secondary heart field-derived smooth muscle with the neural crest-derived smooth muscle. Both of these seams are points where aortic dissection frequently occurs in Marfan's and other syndromes. 相似文献
110.
A.M. Rizk F.M. Hammouda M.M. El-Missiry H.M. Radwan F.J. Evans 《Phytochemistry》1984,23(10):2377-2379
An ether soluble resin was prepared by extraction and partition of the latex of Euphorbia royleana. This resin demonstrated pronounced pro-inflammatory activity on mammalian skin and was separated into biologically active and inactive fractions by dry column chromatography. The inactive fraction was further separated by adsorption and partition thin-layer methods. The least polar zone consisted of an inseparable mixture of four tetra-esters of the macrocyclic diterpene ingol, whilst the more polar fraction consisted of a mixture of four tri-esters of the same diterpene. 相似文献