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1.
2.
Identification of a gene disrupted by a microdeletion in a patient with X-linked retinitis pigmentosa (XLRP) 总被引:2,自引:2,他引:2
Roepman R; Bauer D; Rosenberg T; van Duijnhoven G; van de Vosse E; Platzer M; Rosenthal A; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(6):827-833
The gene for the most frequent from of X-linked retinitis pigmentosa
(XLRP), RP3, has been assigned by genetic and physical mapping to a segment
of less than 1000 kbp, which is flanked by the marker DXS1110 and the
ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have
screened the DNA of 30 unrelated patients with XLRP by employing a
representative set of YAC-derived DNA fragments that were generated by
restriction enzyme digestion and PCR amplification. In one of these
patients, a 6.4 kbp microdeletion was detected which was not present in the
DNA of 444 male controls. A cosmid contig spanning the deletion was
constructed and used to isolate cDNAs from retina-specific libraries. Exons
corresponding to these expressed sequences as well as other putative exons
were identified by sequencing more than 30 kbp of the critical region. So
far, no point mutations in these putative exon sequences have been
identified.
相似文献
3.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
4.
Identification of a new locus for autosomal dominant non-syndromic hearing impairment (DFNA7) in a large Norwegian family 总被引:3,自引:0,他引:3
Fagerheim T; Nilssen O; Raeymaekers P; Brox V; Moum T; Elverland HH; Teig E; Omland HH; Fostad GK; Tranebjaerg L 《Human molecular genetics》1996,5(8):1187-1191
Hereditary hearing impairment affects about 1 in 1000 newborns. In most
cases hearing loss is non-syndromic with no other clinical features, while
in other families deafness is associated with specific clinical
abnormalities. Analysis of large families with non-syndromic and syndromic
deafness have been used to identify genes or gene locations that cause
hearing impairment. The present report describes a large Norwegian family
with autosomal dominant non-syndromic, progressive high tone hearing loss
with linkage to 1q21-q23. A maximum LOD score of 7.65 (theta = 0.00) was
obtained with the microsatellite marker D1S196. Analysis of recombinant
individuals maps the deafness gene (DFNA7) to a 22 cM region between D1S104
and D1S466. The region contains several attractive candidate genes. This
report supports the idea of extensive genetic heterogeneity in hereditary
hearing impairment and represents the first localization of a deafness gene
in a Norwegian family.
相似文献
5.
M J Ackerman B L Siu W Q Sturner D J Tester C R Valdivia J C Makielski J A Towbin 《JAMA》2001,286(18):2264-2269
CONTEXT: Fatal arrhythmias from occult long QT syndrome may be responsible for some cases of sudden infant death syndrome (SIDS). Because patients who have long QT syndrome with sodium channel gene (SCN5A) defects have an increased frequency of cardiac events during sleep, and a recent case is reported of a sporadic SCN5A mutation in an infant with near SIDS, SCN5A has emerged as the leading candidate ion channel gene for SIDS. OBJECTIVE: To determine the prevalence and functional properties of SCN5A mutations in SIDS. DESIGN, SETTING, AND SUBJECTS: Postmortem molecular analysis of 93 cases of SIDS or undetermined infant death identified by the Medical Examiner's Office of the Arkansas State Crime Laboratory between September 1997 and August 1999. Genomic DNA was extracted from frozen myocardium and subjected to SCN5A mutational analyses. Missense mutations were incorporated into the human heart sodium channel alpha subunit by mutagenesis, transiently transfected into human embryonic kidney cells, and characterized electrophysiologically. MAIN OUTCOME MEASURES: Molecular and functional characterization of SCN5A defects. RESULTS: Two of the 93 cases of SIDS possessed SCN5A mutations: a 6-week-old white male with an A997S missense mutation in exon 17 and a 1-month old white male with an R1826H mutation in exon 28. These 2 distinct mutations occurred in highly conserved regions of the sodium channel and were absent in 400 control patients (800 alleles). Functionally, the A997S and R1826H mutant channels expressed a sodium current characterized by slower decay and a 2- to 3-fold increase in late sodium current. CONCLUSION: Approximately 2% of this prospective, population-based cohort of SIDS cases had an identifiable SCN5A channel defect, suggesting that mutations in cardiac ion channels may provide a lethal arrhythmogenic substrate in some infants at risk for SIDS. 相似文献
6.
Ramirez Valdivia MT Crowe TJ 《International journal of health care quality assurance incorporating Leadership in health services》1997,10(4-5):208-212
Patient satisfaction is becoming increasingly important for the successful operation of private and public hospitals. The quality of the service provided can be improved if internal and external customers' opinions are taken into account during the definition of hospital operating objectives. This research presents a new methodology, called the simulation service quality system (SSQS), developed to improve operating performance measures in the light of customer preferences. The motivation for the development of the SSQS methodology arose from the need to achieve timeliness standards at United States Veterans' Hospitals. The Harry S. Truman Memorial Veterans' Hospital in Columbia Missouri served as the validation and initial application site for the SSQS methodology. Details one such project: the objective of reducing customer waiting times to 30 minutes or less at an outpatient treatment clinic. Through the identification of relationships and interactions, discrete-event simulation techniques are applied to model and experiment with the system to ultimately arrive at recommended changes in hospital operating policies which achieve the objective. 相似文献
7.
8.
Two girls (a 5 year old and a 21 month old) experiencing mononucleosis syndrome with coincidental human herpesvirus (HHV)-7 and Epstein-Barr virus (EBV) infections are described. One patient had primary HHV-7 infection and reactivated EBV infection. The other had primary HHV-7 and EBV infections. These cases indicated that HHV-7 is capable of inducing infectious mononucleosis-like illness. Multiple herpesvirus infection in one of the patients also suggests that interaction among herpesviruses can occur in vivo. The consequence of this interaction may have clinical implications. 相似文献
9.
Zhang JD Cao YB Xu Z Sun HH An MM Yan L Chen HS Gao PH Wang Y Jia XM Jiang YY 《第二军医大学学报》2006,27(6):664-664
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans. 相似文献