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1.
In this review, structures of natural products isolated from the soft corals of genus Cladiella and their biological activities are described.  相似文献   
2.
首次从魔芋中分离出由特殊羟基脂肪酰基构成的脑苷脂类化合物.通过光谱和化学方法鉴定为1-O-β-D-吡喃葡萄糖-(2S,3R,4E,8Z)-2-(2'R-羟基脂肪酰基)-正十八碳-4,8-二烯鞘胺醇.其中羟基脂肪酰基主要由2-羟基-正十六酰基,2-羟基-正十八酰基,2-羟基-正二十酰基,2-羟基-正二十二酰基,2-羟基-正二十四酰基组成.  相似文献   
3.
Acylgalactosylceramides (AGC) from forebrains of normal and dysmyelinating (quaking and shiverer) mice were purified by Florisil column chromatography and preparative TLC. These procedures resolved the AGC on the basis of their Rf values into two main fractions which co-nigrate with their homologs from rat forebrains. In control animals, AGC were detectable in mouse forebrains from the eighth postnatal day and reached maximal values within 20 days. The same developmental pattern was obtained in dysmyelinating shiverer mice but the AGC content was reduced to approximately 30% of control values. In quaking mutants, the AGC were hardly detected. They were also present in sciatic nerve of normal mice and to a lesser extent in trembler mice. Gas chromatography-mass spectrometry analysis of both ester- and amide-linked fatty acids isolated from AGC of normal and shiverer mice shows that the shiverer mutant AGC display a chemical structure similar to that of normal AGC. AGC constituents of control myelin are reduced by approximately 70% in shiverer myelin, indicating that these molecules can be considered as early markers of oligodendrocyte differentiation. The early arrest of myelinogenesis in the quaking animals and the near absence of AGC are in good agreement with this proposal. Moreover, the reduced amount of AGC in the trembler PNS indicates that AGC could also be early markers for differentiation of the Schwann cell.  相似文献   
4.
Lipid composition was studied on cerebral tissue from nine children who had died of a progressive encephalopathy called the infantile form of neuronal ceroid lipofuscinosis (INCL) or polyunsaturated fatty acid lipidosis (PFAL). In the terminal stage of the disease, the concentrations of all lipid classes were found to be significantly reduced in the cerebral and cerebellar cortex and white matter. The concentration of gangliosides of the cerebral cortex was 15% and that of cerebrosides (galactosylceramide) in white matter 0.2-5% of the normal values for the children's ages. The reduction of gangliosides mainly affected those of the gangliotetraose series, particularly GD1a. The fatty acids of the linolenic acid series were strongly reduced in ethanolamine and serine phosphoglycerides. A very large increase up to 100-fold of oligoglycosphingolipids of the globo series and two fucose-containing lipids of the neolacto series was found in the forebrain of the three advanced cases examined. The brain tissue also contained very high concentrations of mono-, di-, and trisialogangliosides of the lacto and neolacto series, gangliosides with type 1 chain dominating. The structures of the gangliosides were tentatively identified by gas chromatography-mass spectrometry and monoclonal antibodies with carefully determined epitope specificity. The gangliosides and neutral glycosphingolipids had very similar fatty acid composition, consisting of about 40% stearic acid and 40% C24-acids.  相似文献   
5.
The haemagglutinating activity of the membrane-associated Schistosoma mansoni “agglutinin” is mainly due to acidic phospholipids, particularly phosphatidylinositol and phosphatidylserine. The role of these phospholipids in possible lipid-protein interactions in the host-parasite relationship is discussed.  相似文献   
6.
一株茄病镰刀菌(Fusarium solani)固体发酵培养物经柱层析分离得到10个化合物。通过波谱分析,分别鉴定为对羟基苯甲酸甲酯(1)、水杨酸甲酯(2)、水杨酸戊酯(3)、香草乙酮(4)、草夹竹桃苷(5)、2-甲氧基-4-乙烯苯基-β-D-吡喃葡萄糖苷(6)、1-O-β-D-glucopyranosyl-(2S,3R,8E)-2-[(2R)-2-hydroxylpalmitoylamino]-8-octadecene-1,3-diol(7)、1-O-β-D-glucopyranosyl-(2S,3R,4E,8E)-2-[(2R)-2-hydroxyhexadecanoylaino]-8-octadecene -1,3-diol (8)、脑苷脂D(9)和脑苷脂C(10)。所有化合物均为首次从茄病镰刀菌中分离得到,其中化合物6首次作为天然产物报道。  相似文献   
7.
阳春砂仁的化学成分研究   总被引:1,自引:0,他引:1  
从阳春砂仁Amomum villosum Lour.中分离得到14个化合物,经理化常数和波谱分析鉴定其结构分别为槲皮素(1)、槲皮苷(2)、异槲皮苷(3)、香草酸(4)、3,4-二羟基苯甲酸(5)、β-谷甾醇(6)、胡萝卜苷(7)、豆甾醇(8)、麦角甾醇(9)、麦角甾-7,22-二烯-3β,5α,6β-三醇(10)、硬脂酸(11)、棕榈酸(12)、白附子脑苷B(13)和虎杖苷(14)。其中,化合物1、9、10、13和14为首次从该种植物中分离得到。  相似文献   
8.
脑甙类化合物的研究概况   总被引:1,自引:0,他引:1  
首次对近些年来国内、外对存在于动物、植物和海洋生物中的单糖脑甙类化合物(cerebrosides)的结构进行分类和光谱分析,并结合自己的实际工作经验提出了针对这类化合物的结构鉴定见解,同时也总结了它们的生物活性。  相似文献   
9.
This paper describes the work of five scientists who, among others, carried on the work of J. L. W. Thudichum, the pre-eminent investigator of brain chemistry in the latter half of the 19th century, after his death in 1901. This paper is dedicated to my friend Moussa Ben-Hur Youdim, who spent three years (1963–1966) in my laboratory, as a graduate student in the Department of Biochemistry, McGill University. During this time, Moussa purified monoamine oxidase of rat liver, and provided the first evidence of its multiplicity. He also contributed to the recognition of iron and riboflavin as constituents of the enzyme.  相似文献   
10.
Protein and Lipid Composition of Radial Component-Enriched CNS Myelin   总被引:3,自引:1,他引:2  
Abstract: The radial component is a junctional complex that is believed to stabilize the apposition of myelin membranes in the internode of CNS myelin. Based on our previous finding that the radial component of compact myelin retains its structure in tissue treated with the detergent Triton X-100, we have attempted to isolate the junctional complex from spinal cord myelin treated with this detergent. Using 0.5% Triton X-100, our procedures yielded a fraction of isolated myelin that was enriched in well-preserved radial component. This fraction that contained morphologically well-defined radial component was examined by sodium dodecyl sulfate-polyacrylamide gel electropho-resis and immunoblotting, and TLC, and was found to be significantly and consistently enriched in the 21.5-kDa and 17-kDa isoforms of myelin basic protein, and in cerebro-sides, hydroxy sulfatide, and sphingomyelin. In addition, the myelin-associated enzyme 2',3'-cyclic nucleotide 3'-phosphodiesterase, tubulin, and actin tended to be resistant to Triton extraction. The fraction of isolated myelin that contained radial component was deficient in proteolipid protein and DM-20, the 18.5-and 14-kDa isoforms of myelin basic proteins, and in the major phospholipids, phosphatidylethanolamine, phosphatidylcholine, and phosphatidylserine. Our data indicate that the radial component can be isolated and that certain myelin and cytoskeletal proteins and lipids are closely associated with it.  相似文献   
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