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41.
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
42.
We present a family consisting of a mother, a daughter, and a son with Teebi hypertelorism syndrome, including some previously unrecognized manifestations. The clinical findings include a prominent forehead, arched eyebrows, pronounced hypertelorism, long philtrum, mild interdigital webbing, fifth-finger clinodactyly, umbilical anomalies, and hypotonia. The mother and daughter also had ptosis requiring surgical correction. The daughter has bilateral iridochorioretinal colobomas with high hyperopia and a small umbilical hernia. The son has less striking facial features but was born with a small omphalocele, large ASD secundum, PDA, bilateral cryptorchidism right hydronephrosis, and a cystic left kidney. The mother had an umbilical hernia requiring surgical correction as a child and a history of heart murmur. Both children have normal hearing and mild developmental delay. Their high-resolution karyotypes were normal and the FISH for 22q11 microdeletion was negative in the daughter. We conclude that cardiac defects in Teebi hypertelorism syndrome are not rare findings and that eye colobomas and renal anomalies were previously unrecognized. 相似文献
43.
Rao KR Kauser F Srinivas S Zanetti S Sechi LA Ahmed N Hasnain SE 《Journal of clinical microbiology》2005,43(12):5978-5982
Mycobacterium tuberculosis, the etiological agent of tuberculosis, has lost many coding and noncoding regions in its genome during the course of evolution. We performed region-of-difference (RD) analysis using PCR-based genotyping of 131 M. tuberculosis clinical isolates obtained from four different countries, namely, India, Peru, Libya, and Angola. Our studies revealed that RD patterns are often distinct for strains circulating in specific geographical regions and can be used to trace the descent and spread of an isolate from its original reservoir. We describe our findings, which show that no single isolate from the four countries (n = 131) had all the 15 RDs either deleted or retained. Tuberculosis-specific deletion 1 (TbD1) was found to be conserved in 23% of the Indian isolates, indicating their possible ancient origin. RD9 was the most conserved region, RD11 was predominantly deleted, and RD6 was the most variable among the isolates in our collection irrespective of their geographic region. In contrast to earlier reports, our results demonstrate that the deletion of RD1 does not correlate with a decrease in the virulence potential of M. tuberculosis, as Indian isolates (n = 30) examined by us were from diseased individuals and yet had lost the RD1 region. Our results further illustrated that the intactness of the RD5 region may be associated with increased virulence of the organism. This study highlights that the RDs in M. tuberculosis genomes are geographically distributed and specific and may possibly be associated with virulence spectrum. 相似文献
44.
Cognitive profiles and the spectrum of clinical manifestations in heterozygous fra (X) females 总被引:6,自引:0,他引:6
M B Kemper R J Hagerman R S Ahmad R Mariner 《American journal of medical genetics》1986,23(1-2):139-156
We investigated the possibility that fra(X) heterozygotes had a distinct or specific set of mental deficits ("cognitive profile") which would allow for accurate diagnosis. Wechsler Intelligence Scale for Children-Revised (WISC-R) subtest scores obtained on 8 fra(X) school age girls were compared with similar scores obtained on 8 "learning-disabled" non fra(X) girls matched on the basis of Full Scale IQ (FSIQ). The Block Design subtest score was significantly lower in fra(X) girls. In a larger sample of 22 fra(X) females, a characteristic combination of low Arithmetic, Digit Span, and Block Design subtest scores was observed. The mean discrepancy between these 3 subtest scores from the total Verbal or Performance subtest means was significant for the fra(X) group but not for a comparison group of 20 learning-disabled females. Verbal IQ (VIQ) and Performance IQ (PIQ) discrepancy was not significant in fra(X) females. Percent fra(X) positive cells was negatively correlated with VIQ and FSIQ but not with PIQ. 相似文献
45.
The effect of the growth state of a cell on the ability of hyperthermia to induce the synthesis of heat shock proteins (HSPs) was studied in resting and concanavalin A (ConA)-stimulated lymphocytes. Hyperthermia induced the synthesis of hsp 110, hsp 90, hsc 70, and hsp 70 in both resting and ConA-stimulated lymhocytes, and ConA-treatment induced the synthesis of the hsp 90 and hsc 70 at normal temperature. The induction of the synthesis of hsp 110 and hsp 70 by hyperthermia was 3- to 6-fold higher for lymphocytes cultured with ConA for 12 and 24 h than in non-stimulated lymphocytes. Thus, lymphocytes induced to undergo proliferation showed a greater response to hyperthermia than resting lymphocytes. 相似文献
46.
Beck FW Al-Katib AM Ahmad I Wall NR Liu KZ Mantsch HH Mohammad RM 《International journal of molecular medicine》2000,5(4):341-347
WSU-CLL cells, a fludarabine resistant B-cell chronic lymphocytic leukemia cell line, has been shown to exhibit enhanced sensitivity to 2-chlorodeoxyadenosine (2-CdA) following 48-72 h exposure to bryostatin 1. For 2-CdA to manifest its chemotherapeutic activity, it must first enter the cell through one of several specific nucleoside transporter systems. We present data to show that bryostatin 1-induced enhanced influx of 2-CdA is in part the result of bryostatin 1-induced modulation of nucleoside transporters in WSU-CLL cells. The bi-directional equilibrative NBMPR sensitive transporters in WSU-CLL cells were significantly down-regulated 90 min post-exposure to 1-200 nM bryostatin 1. This down-regulation was evident up to 144 h. In contrast, WSU-CLL cells exhibited a transient increase in Na+-dependent concentrative 2-CdA influx from 48 to 96 h after bryostatin 1 exposure which was evident for a longer duration than that accounted for by the increase in deocycytidine kinase activity. These data may, in part, explain the enhanced efficacy of 2-CdA seen in WSU-CLL cells following 48-72 h exposure to bryostatin 1. It may raise questions as to the importance of the bi-directional transporters in determining the resistance or sensitivity of CLL cells to 2-CdA or other nucleoside analogues. 相似文献
47.
Wajid M Abbasi AA Ansar M Pham TL Yan K Haque S Ahmad W Leal SM 《European journal of human genetics : EJHG》2003,11(10):812-815
This article describes the identification of a novel locus (DFNB39) responsible for an autosomal recessive form of hearing loss segregating in a Pakistani consanguineous family. The hearing impaired members of this family present with profound prelingual sensorineural hearing impairment and use sign language for communications. Linkage was established to microsatellite markers located on chromosome 7q with a maximum multipoint lod score of 3.8. The region of homozygosity spans a 19 cM region that is bounded by markers D7S3046 and D7S644. 相似文献
48.
Riazimand SH Brieger J Jacob R Welkoborsky HJ Mann WJ 《Cancer Genetics and Cytogenetics》2002,136(1):53-57
Esthesioneuroblastoma (ENB) are rare tumors originating from the olfactory epithelium of the superior nasal cavity. This lesion is morphologically closely related to Ewing sarcoma and other peripheral primitive neuroectodermal tumors (pPNET). The affiliation of ENB to the pPNET family is still under discussion. Only very limited and contradictory cytogenetic data are available on ENB and only one patient has been analyzed by comparative genomic hybridization (CGH), so far. In the present study, genomic imbalances of three ENB were analyzed by CGH to evaluate (1) a recurrent pattern of imbalances, and (2) its relation to the pPNET family. The CGH analysis of three ENB revealed multiple recurrent aberrations including DNA overrepresentations of chromosomal material of the entire chromosome 19, partial gains of the long arms of chromosomes 8, 15, and 22, and deletions of the entire long arm of chromosome 4. Beside these common aberrations, several single gains and losses occurred, that is, gains on 6p, 10q, 1p, 9q, and 13q. We confirmed the former observation of amplified genetic material on chromosome 8 and found several new, currently not described recurrent genetic aberrations distinct from those described for pPNET. Our findings give evidence that ENB is not part of the pPNET family. We suggest that the combined gain of genetic material on 15q, 22q, and chromosome 8 might be indicative for ENB. To verify our findings and to define prognosis-related aberrations, a larger number of cases needs to be studied. 相似文献
49.
Jones DC Gelder CM Ahmad T Campbell IA Barnardo MC Welsh KI Marshall SE Bunce M 《Tissue antigens》2001,58(1):19-23
Mycobacterium malmoense is an opportunistic mycobacterium that occasionally causes disease in non-immunosuppressed individuals. As only a few individuals exposed to these organisms actually develop clinical disease, it is possible there is a genetic component to susceptibility. CD1 molecules are capable of presenting antigens from more virulent mycobacteria to T cells; therefore, we were interested in discovering whether recently described polymorphisms in CD1 molecules modulated susceptibility to M. malmoense pulmonary disease. The CD1 system comprises five genes (CD1A, -B, -C, -D, and -E) located on chromosome 1 (1q22-23). CD1 molecules are structurally and functionally related to major histocompatibility complex (MHC) class I molecules and are expressed on dedicated antigen-presenting cells. The primary function of CD1 molecules is to present lipid and glycolipid antigens to T cells. We have developed an allele-specific polymerase chain reaction-sequence-specific primer (PCR-SSP) method of CD1 genotyping. Using this method, we compared the allele and haplotype frequencies of CD1 in 49 HIV-negative patients with M. malmoense pulmonary disease with those in 342 normal controls. The CD1A and CD1E alleles were nominally identified as CD1A*01, CD1A*02, CD1E*01 and CD1E*02, and the control gene frequencies were found to be 5%, 95%, 67% and 33%, respectively. No significant difference was observed between the patient and control cohorts. Positive linkage disequilibrium values of 0.73 were observed between CD1A*02 and CD1E*01 (P<0.0001; chi2 test), and 0.94 between CD1A*01 and CD1E*02 (P<0.0001; chi2 test). Typing was also performed for two previously described CD1D alleles (CD1D*01 and CD1D*02), although only CD1D*01 was detected. 相似文献
50.
G N Gephardt L F Shah R R Tubbs M Ahmad 《Archives of pathology & laboratory medicine》1990,114(9):961-965
Four cases of Wegener's granulomatosis involving lung are reported in which immunomicroscopy demonstrated that the parenchymal and vascular infiltrates were composed primarily of T cells and monocytes. No IgG, IgA, IgM, or C3 was identified in pulmonary vessels or alveolar septa. Ultrastructural studies failed to demonstrate dense deposits in alveolar septal capillaries or interstitium. These findings indicate that a cellular immune mechanism is active in these forms of pulmonary vasculitis and that immune complex deposition does not play a role. 相似文献