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31.
Ahmad Soolari 《Quintessence international, dental digest》2002,33(5):389-396
Periodontal disease is a chronic disease that is perceived by many patients to be nonthreatening. Periodontal therapy has been shown to be less effective if a regular periodontal maintenance schedule is not followed after completion of active therapy. Periodontal maintenance is an integral part of successful periodontal therapy. 相似文献
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Singh Shivendra V.; Haque Abida K.; Ahmad Hassan; Medh Rheem D.; Awasthi Yogesh C. 《Carcinogenesis》1988,9(9):1681-1685
In the present studies we have compared the levels of glutathione(GSH) and GSH-related enzymes in lung tumors and correspondingnormal tissues obtained from the same individuals. We have alsoimmunologically quantitated the relative amounts of glutathioneS-transferase (or GST-P) type antigen in tumors and adjacentnormal tissues from five patients. GST activities towards 1-chloro-2,4-dinitrobenzene (CDNB) and ethacrynic acid were found to beelevated in tumors from two out of five patients (patients #1and 4), whereas the activity towards these substrates was markedlysuppressed in the tumor tissue from one of the patients (#5).Immunotitration and Western blot studies using antibodies raisedagainst -type GST isoenzymes of human lung and placenta indicatedinduction of GST -type isoenzyme in tumors from patients #1and 4 and suppression of this isoenzyme in tumor from patient#5. The tumors from patients #2 and 3 did not show any increasein GST activity or GST -type antigen. Except for the tumor frompatient #5, the GSH content was higher in the tumors from otherpatients. GSH reductase activity was found to be elevated intumors of all the patients examined in this study. These resultsindicate that GSH and GSH related enzymes are differentiallyaltered in lung tumors and GSH levels and GST - or GST-P-typeisoenzyme(s) are not uniformly elevated in all tumors. 相似文献
34.
Daher A de Boer WI El-Marjou A van der Kwast T Abbou CC Thiery JP Radvanyi F Chopin DK 《Laboratory investigation; a journal of technical methods and pathology》2003,83(9):1333-1341
Members of the epidermal growth factor (EGF) family and their receptors are involved in many cellular processes, including proliferation, migration, and differentiation. We have previously reported that these growth factors are expressed and have specific regulatory functions in an organ-like culture model of normal human urothelial cells. Here, we used this model to investigate the involvement of EGF receptor (EGFR) in human urothelial regeneration. Three 4-mm-diameter damaged areas were made in confluent normal human urothelial cell cultures with a biopsy punch. Regeneration was measured, on fixed stained cultures, with an image analyzer, at 4, 24, and 48 hours after injury. Cell proliferation was assessed by 5-bromo-2-deoxyuridine incorporation. To identify EGF family factors potentially involved in the healing process, we studied the effect of these factors on damaged confluent cultures and the level of expression of mRNAs extracted from these cultures. EGFR inhibition of the proliferation and migration of urothelial cells was tested with (1). a specific tyrosine kinase inhibitor (AG1478) and (2). a blocking anti-EGFR antibody (LA22). Exogenously added amphiregulin, EGF, transforming growth factor-alpha and heparin-binding EGF (HB-EGF) stimulated urothelial regeneration. The damaged areas were repaired by regrowth within 48 hours. Both AG1478 and LA22 inhibited the repair (by 50% and 30%, respectively), as well as proliferation and migration. This regeneration was accompanied by increased HB-EGF mRNA expression in cultures of cells from four of six subjects, but no corresponding change in EGFR protein level was observed. These results indicate that the EGFR signaling pathway is involved in urothelial regeneration. Our data support an autocrine role of HB-EGF in this process and suggest that the EGFR pathway is a potential therapeutic target for modulating urothelial cell proliferation. 相似文献
35.
Ansar M Din MA Arshad M Sohail M Faiyaz-Ul-Haque M Haque S Ahmad W Leal SM 《European journal of human genetics : EJHG》2003,11(1):77-80
Autosomal recessive nonsyndromic deafness is one of the most frequent forms of inherited hearing impairment. Over 30 autosomal recessive nonsyndromic hearing loss loci have been mapped, and 15 genes have been isolated. Of the over 30 reported autosomal recessive nonsyndromic hearing loss (NSHL) loci, the typical phenotype is prelingual non-progressive severe to profound hearing loss with the exception of DFNB8, which displays postlingual onset and DFNB13, which is progressive. In this report we describe a large inbred kindred from a remote area of Pakistan, comprising six generations and segregating autosomal recessive nonsyndromic prelingual deafness. DNA samples from 24 individuals were used for genome wide screen and fine mapping. Linkage analysis indicates that in this family the NSHL locus, (DFNB35) maps to a 17.54 cM region on chromosome 14 flanked by markers D14S57 and D14S59. Examination of haplotypes reveals a region that is homozygous for 11.75 cM spanning between markers D14S588 and D14S59. A maximum two-point LOD score of 5.3 and multipoint LOD score of 7.6 was obtained at marker D14S53. The interval for DFNB35 does not overlap with the regions for DFNA9, DFNA23 or DFNB5. 相似文献
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38.
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
39.
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
40.