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排序方式: 共有2161条查询结果,搜索用时 24 毫秒
11.
Julio C Delgado Ahasan Hameed Juan J Yunis Kailash Bhol Adriana I Rojas Simeen B Rehman Ashfaq A Khan Manzoor Ahmad Chester A Alper A.Razzzaque Ahmed Edmond J Yunis 《Human immunology》1997,57(2):110-119
ABSTRACT: Pemphigus vulgaris (PV) is an autoimmune disease of the skin and mucous membranes characterized by an autoantibody response against an epidermal cadherin. We performed high resolution HLA class II typing in 19 patients with PV from Rawalpindi, Pakistan and 19 non-Jewish European PV patients from Boston by sequence-specific oligonucleotide probe hybridization. The results were compared with two separate ethnically matched control populations. We found that PV patients from Pakistan had significantly increased frequencies of DRB1*1404 ( p = 0.01), DQA1*0101 ( p = 0.02), and DQB1*0503 ( p = 0.01). Among the patients of non-Jewish European ancestry, DRB1*1401 ( p < 10−6), DQA1*0101 ( p < 10−5) and DQB1*0503 ( p < 10−6), were increased in PV patients. Formal linkage analysis between the major histocompatibility complex and the PV antibody was performed in 67 relatives of the 19 Pakistani patients. The results showed strong evidence for linkage of HLA-DRB1*1404, DQA1*0101, DQB1*0503, with the presence of PV antibody in relatives’ families with a significant logarithm of the odds score of 6.06. Based on the three dimensional structure of class II molecules, we propose that HLA-DQA1*0101 and DQB1*0503, encode a negatively charged P9 peptide binding pocket of the DQ molecule and are significantly associated with susceptibility to PV in non-Jewish populations. 相似文献
12.
[31P]-Nuclear magnetic resonance (NMR) in vivo spectra ofEchinococcus multilocularis cysts growing subcutaneously inMeriones unguiculatus showed prominent signals due to phosphomonoesters (PME), phosphodiesters (PDE), inorganic phosphate (Pi) and the , and phosphate groups of adenosine triphosphate (ATP). The internal pH of the parasite cysts was 6.7–6.8. The31P spectra of extracts of these subcutaneous cysts showed peaks identified as glucose-6-phosphate (Glu-6-P), glycerol-3-phosphate (Gly-3-P), phosphorylethanolamine (PE), adenosine-5-monophosphate (5-AMP), nicotinamide adenine dinucleotide phosphate (NADP), phosphorylcholine (PC), Pi, glycerolphosphorylethanolamine (GPE), glycerolphosphorylcholine (GPC), phosphoenolpyruvate (PEP), adenosine diphosphate (ADP), ATP and diphosphodiesters (DPDE). These metabolites were also detected at comparable concentrations in the extracts of intraperitoneally grown cysts. In addition, significantly more phosphocreatine (PCr), probably of host origin, was detected in the subcutaneous cysts than in the intraperitoneal cysts. [1H]-NMR spectra of cyst extracts revealed that parasites grown in the abdominal cavity contained significantly less glucose but significantly more succinate, acetate, alanine and -hydroxybutyrate. Glycogen, creatine, glycine, taurine, betaine, cholines and lactate were present at similar concentrations in cyst material from both locations. 相似文献
13.
Barbashina V Heller DS Hameed M Albanese E Goldstein M Dashefsky B Dieudonne A Chakraborty R 《Virchows Archiv : an international journal of pathology》2000,436(2):138-139
Smooth-muscle neoplasms are rarely located in the spleen. They have been previously reported in five cases of children with
human immunodeficiency virus (HIV) infection/acquired immunodeficiency syndrome (AIDS). Two cases of children with HIV infection/AIDS
with autopsy and surgical pathology evidence of multiple smooth-muscle neoplasms with splenic involvement are presented. DNA
was extracted from histology slides in both cases for analysis for Epstein Barr (EB) virus. In both cases, the presence of
EB virus was confirmed. This paper documents two additional cases of the unusual phenomenon of splenic involvement by smooth-muscle
neoplasms in the setting of AIDS in childhood and further supports the role of EB virus in the development of these neoplasms.
Received: 27 January 1999 / Accepted: 23 August 1999 相似文献
14.
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16.
Norman PJ Carrington CV Byng M Maxwell LD Curran MD Stephens HA Chandanayingyong D Verity DH Hameed K Ramdath DD Vaughan RW 《Genes and immunity》2002,3(2):86-95
Natural killer (NK) and some T cells express killer cell immunoglobulin-like receptors (KIRs), which interact with HLA class I expressed by target cells and consequently regulate cytolytic activity. The number of KIR loci can vary and so a range of genetic profiles is observed. We have determined the KIR genetic profiles from one African (n = 62) and two South Asian (n = 108, n = 78) populations. Several of the KIRs are present at significantly different frequencies between the two major ethnic groups (eg KIR2DS4 gene frequency 0.82 African, 0.47 S Asian. Pc < 1 x 10(-6)) and this is due to uneven distribution of two KIR haplotype families 'A' and 'B'. All three populations described here displayed a greater degree of diversity of KIR genetic profiles than other populations investigated, which indicates further complexity of underlying haplotypes; in this respect we describe two individuals who appear homozygous for a large deletion including the previously ubiquitous 2DL4. We have also reanalysed three populations that we studied previously, for the presence of a KIR which is now known to be an indicator of the 'B' haplotype. South Asians had the highest overall frequencies of all KIR loci characteristic of 'B' haplotypes (Pc < 0.0001 to < 0.004). Furthermore, gene frequency independent deviances in the linkage disequilibrium were apparent between populations. 相似文献
17.
Isolation of a new clathrin heavy chain gene with muscle-specific expression from the region commonly deleted in velo-cardio-facial syndrome 总被引:3,自引:4,他引:3
Sirotkin H; Morrow B; DasGupta R; Goldberg R; Patanjali SR; Shi G; Cannizzaro L; Shprintzen R; Weissman SM; Kucherlapati R 《Human molecular genetics》1996,5(5):617-624
Velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome (DGS) are
developmental disorders characterized by a spectrum of phenotypes including
velopharyngeal insufficiency, conotruncal heart defects and facial
dysmorphology among others. Eighty to eighty-five percent of VCFS/DGS
patients are hemizygous for a portion of chromosome 22. It is likely that
the genes encoded by this region play a role in the etiology of the
phenotypes associated with the disorders. Using a cDNA selection protocol,
we isolated a novel clathrin heavy chain cDNA (CLTD) from the VCFS/DGS
minimally deleted interval. The cDNA encodes a protein of 1638 amino acids.
CLTD shares significant homology, but is not identical to the ubiquitously
expressed clathrin heavy chain gene. The CLTD gene also shows a unique
pattern of expression, having its maximal level of expression in skeletal
muscle. Velopharyngeal insufficiency and muscle weakness are common
features of VCFS patients. Based on the location and expression pattern of
CLTD, we suggest hemizygosity at this locus may play a role in the etiology
of one of the VCFS-associated phenotypes.
相似文献
18.
Mahadevan MM; McIntosh Q; Miller MM; Breckinridge SM; Maris M; Moutos DM 《Human reproduction (Oxford, England)》1998,13(4):979-982
Cryopreservation of human zygotes and embryos has been routinely performed
by in-vitro fertilization clinics for many years. Karran and Legge (1996)
first reported that formaldehyde (FA) present in the cryoprotective
solutions can have a deleterious effect on mouse oocytes. FA is a
cytotoxic, carcinogenic and mutagenic chemical. The effect of FA on mouse
zygotes was investigated. In addition, the concentrations of FA in
propanediol (PROH) obtained from various sources were determined. Pooled
1-cell embryos were dispensed into droplets of modified Ham's F10 or human
tubal fluid containing various concentrations of FA. Since bovine serum
albumin (BSA) may minimize toxicity additional trials were done as above in
the absence of BSA. FA concentration in the standard 1.5 M PROH, from
different sources in water, was measured in the same assay using a standard
curve of 0-100 microM FA. FA in a complex medium had a significant
deleterious effect on embryo development and hatching but only at 1 mM
concentration (P < 0.000001; see Tables I-III). There was no significant
effect of FA at 100 microM. However, in a simple medium even 50 microM FA
decreased embryo hatching. FA was present in 1.5 M PROH from different
sources (range 1.0-35.3 microM concentration). It appears that FA
concentrations do not increase with storage because FA concentrations were
low even after opening and storage for 3 years on the shelf. This suggests
that FA is a contaminant during the manufacturing process and may vary from
manufacturer to manufacturer and batch to batch. Until further studies are
done to confirm the lack of toxicity to embryos during cryopreservation
(with or without FA scavengers) it may be prudent to screen all batches of
cryoprotectants for FA as part of quality control.
相似文献
19.
20.
Glycoproteins present in human follicular fluid that inhibit the zona- binding capacity of spermatozoa 总被引:1,自引:0,他引:1
Previous studies have suggested that human follicular fluid contains
factors that reduce the zona-binding capacity of spermatozoa. The present
study provides further evidence of the existence of such factors. Using the
hemizona binding assay (HZA), we have shown that the inhibitory effect of
human follicular fluid on the zona-binding capacity of spermatozoa is
concentration-dependent, an inhibitory effect being detected when the
concentration of human follicular fluid was > or = 10%. A 1%
concentration of human follicular fluid did not possess this inhibitory
activity. Heating human follicular fluid at 56 degrees C for 30 min did not
affect its inhibitory properties; treatment with proteinase-K abolished
such inhibition. Human follicular fluid was fractionated sequentially by
concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography
and Superose-12 gel filtration. The zona binding inhibitory activity
resided in the fraction which bound to the lectin and Mono Q column and
contained molecules with native molecular weights of 32 and 192 kDa. Sodium
dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that
the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein
remained as a single molecular species under denaturing conditions. We
conclude that two glycoproteins were responsible for the zona binding
inhibitory activity of human follicular fluid. The physiological role of
these factors remains unclear.
相似文献