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491.
DH Geetha M Rajeswari Indhiramuthu Jayashree 《Asian Pacific Journal of Tropical Biomedicine》2013,3(12):985-987
Objective
To determine the possible bioactive components of the ethanolic extract of leaves of Elaeocarpus serratus (E. serratus).Methods
The present research was carried out by using GC-MS analysis, while mass spectra of the compounds found in the extract was matched with the National Institute of Standards and Technology and Wiley library.Results
Thirty components from leaves of the above said plant were identified. The active principles with their retention time, molecular formula, molecular weight and concentration (%) in the ethanol extracts of leaf of E. serratus are obtained.Conclusions
This is the first report of documentation of active constituents from leaves of E. serratus. The research reveals the potential of E. serratus leaves as a good source of bioactive compounds such as fatty acid esters, alcohols, hydrocarbons, aldehydes, alkenes, fatty acids and amides that justify the use of this plant for its various ailments by traditional practitioners. 相似文献492.
Linkage and physical mapping of X-linked lissencephaly/SBH (XLIS): a gene causing neuronal migration defects in human brain 总被引:6,自引:2,他引:6
Ross ME; Allen KM; Srivastava AK; Featherstone T; Gleeson JG; Hirsch B; Harding BN; Andermann E; Abdullah R; Berg M; Czapansky-Bielman D; Flanders DJ; Guerrini R; Motte J; Mira AP; Scheffer I; Berkovic S; Scaravilli F; King RA; Ledbetter DH; Schlessinger D; Dobyns WB; Walsh CA 《Human molecular genetics》1997,6(4):555-562
While disorders of neuronal migration are associated with as much as 25% of
recurrent childhood seizures, few of the genes required to establish
neuronal position in cerebral cortex are known. Subcortical band
heterotopia (SBH) and lissencephaly (LIS), two distinct neuronal migration
disorders producing epilepsy and variable cognitive impairment, can be
inherited alone or together in a single pedigree. Here we report a new
genetic locus, XLIS, mapped by linkage analysis of five families and
physical mapping of a balanced X;2 translocation in a girl with LIS.
Linkage places the critical region in Xq21-q24, containing the breakpoint
that maps to Xq22.3-q23 by high-resolution chromosome analysis. Markers
used for somatic cell hybrid and fluorescence in situ hybridization
analyses place the XLIS region within a 1 cM interval. These data suggest
that SBH and X-linked lissencephaly are caused by mutation of a single
gene, XLIS, that the milder SBH phenotype in females results from random
X-inactivation (Lyonization), and that cloning of genes from the breakpoint
region on X will yield XLIS.
相似文献
493.
Nonrandom inactivation of the X chromosome in early lineage hematopoietic cells in carriers of Wiskott-Aldrich syndrome 总被引:5,自引:7,他引:5
The Wiskott-Aldrich syndrome (WAS) is an X-linked (Xp11.22) recessive immunodeficiency syndrome characterized by susceptibility to opportunistic and pyogenic infections, thrombocytopenia, and eczema. Previous studies of obligate carriers of WAS documented that nonrandom inactivation of the X chromosome carrying the defective gene is observed in all peripheral blood cells. The existence of both abnormal platelets and lymphocytes is consistent with a defect that affects early hematopoietic precursors. We isolated CD34+ hematopoietic progenitor cells collected from obligate carriers of WAS by apheresis and used polymerase chain reaction analysis of a polymorphic variable number of repeats (VNTR) within the X-linked androgen receptor to document nonrandom inactivation. These data show that nonrandom inactivation of the X-chromosome in WAS-obligate carriers occurs early during hematopoietic differentiation. 相似文献
494.
Native tissue plasminogen activator (ntPA) has a variable glycosylation site on its kringle-2 domain. We have examined the effects of kringle glycosylation on functional properties by studying the simplified tPA molecule, tPA-6. tPA-6 is composed of kringle-2 and the serine protease domains and, like ntPA, cells expressing tPA-6 process it into two glycoforms: the monoglycosylated tPA-6-primary (tPA-6P, type II) with N- linked glycosylation at Asn-448 in the serine protease domain and diglycosylated tPA-6-variant (tPA-6V, type I) with glycosylation at Asn- 448 and at Asn-184 in kringle-2. When the two glycoforms were separated, we found that purified tPA-6V had reduced fibrin-stimulated plasminogenolytic activity toward Glu-plasminogen when compared to purified tPA-6P. However, in the presence of fibrin, tPA-6V unexpectedly exhibited a sixfold increase in selectivity toward Lys- plasminogen. In addition, tPA-6V was less susceptible than tPA-6P to plasmin-mediated conversion to the two-chain form. By site-directed mutagenesis of tPA-6, we eliminated variable glycosylation at Asn-184 and engineered a new glycosylation signal at a remnant site in the kringle. This derivative, designated tPA-6D, was secreted with complete kringle glycosylation. Like the naturally occurring tPA-6V, tPA-6D had lower rates of fibrin-stimulated Glu-plasminogen activation, increased specificity toward Lys-plasminogen, and greater resistance to plasmin digestion. Although the activity of tPA-6D could be stimulated by fibrin, its activity was not stimulated significantly by fibrinogen, and in human plasma the rate of fibrinogen depletion was reduced threefold. Although fibrin binding to kringle-2 of tPA-6D was slightly improved, there was a substantial increase in the dissociation constant (kd) for lysine binding, demonstrating a lack of correlation between these ligand-binding sites. Overall, our data demonstrate the marked effect of kringle glycosylation on functional properties. In addition, we have generated a derivative with properties that potentially improve clot specificity and single-chain half-life and reduce the potential for plasminogen activation in the plasma. 相似文献
495.
Abnormal erythroid progenitor cells in human preleukemia 总被引:1,自引:2,他引:1
Ten patients with preleukemia were studied by the erythroid cell clonal culture technique. In nine of these patients, erythroid colonies derived from peripheral blood BFU-E were not observed, while the other patient had markedly decreased peripheral blood BFU-E-derived erythroid colonies in vitro. In three patients, marrow cells were also cultured and no BFU-E-derived erythroid colonies were detected. These studies indicate that immature erythroid progenitor cells, BFU-E, in patients with preleukemia are either markedly decreased in number or grossly defective in their proliferative or differentiative capacities. 相似文献