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Y Ziv

Publications and source records attributed to Y Ziv.

At least 55 records · Page 3Linked to original sources

A YAC contig spanning the ataxia-telangiectasia locus (groups A and C) at 11q22-q23.

Ataxia-telangiectasia (A-T) is an autosomal recessive disease involving cerebellar degeneration, immunodeficiency, cancer predisposition, chromosomal instability and radiosensitivity. A-T is heterogeneous, and the majority of A-T cases are associated with two complementation groups, A and C. The ATA and ATC loci are closely linked at chromosome 11q22-q23. Recombination mapping and linkage disequilibrium analysis have confined both loci between the markers D11S1817 and D11S927, spaced approximately 3.5 Mb apart. Isolation in yeast artificial chromosomes of the genomic segment defined by these loci is essential to identify the gene or genes containing the ATA and ATC mutations. A YAC contig spanning 4.5 Mb, which includes the D11S1817-D11S927 interval, was constructed using two whole genome libraries (ICRF and St. Louis), and a chromosome 11-specific library. Construction of this contig was expedited by prior generation of a region-specific ICRF sublibrary using Alu-PCR products derived from a radiation hybrid. The contig was expanded further by screening the libraries with Alu-PCR products derived from YAC clones and with STSs from YAC ends. YAC clones were aligned by fingerprinting with moderately repetitive probes.

Ataxia Telangiectasia↗

Physical localization of microsatellite markers at the ataxia-telangiectasia locus at 11q22-q23.

The autosomal recessive disorder ataxia-telangiectasia (A-T) is genetically heterogeneous, with four complementation groups. The genes for the two major groups (ATA and ATC) have been mapped to 11q22-q23. Genetic analysis of the disease has been conducted to date using biallelic polymorphisms. We have physically mapped to this region eight new microsatellite markers that were generated by three laboratories that construct whole-genome linkage maps. These markers should be valuable for refined localization and positional cloning of the A-T genes and for diagnostic purposes. The results demonstrate the value of integrating genetic and physical maps generated by different laboratories.

Ataxia Telangiectasia↗

Incidence, risk factors, and treatment of dysplasia in the anal transitional zone after ileal pouch-anal anastomosis.

UNLABELLED: Preservation of the anal transitional zone (ATZ) after restorative proctocolectomy and stapled ileal pouch-anal anastomosis (IPAA) for ulcerative colitis is controversial. PURPOSE: To evaluate the incidence, risk factors, and treatment options for dysplasia and/or cancer after restorative proctocolectomy and stapled IPAA. METHODS: We reviewed the records of all 254 patients operated on for ulcerative colitis who had a restorative proctocolectomy, stapled IPAA, and annual postoperative biopsies of ATZ. Follow-up studies included an annual questionnaire and physical examination. RESULTS: During a follow-up of 2.3 +/- 1.4 (mean +/- standard deviation) years, low-grade dysplasia was found in eight patients (3.1 percent), 16 (median: range, 6-56) months after surgery. Repeated biopsies revealed dysplasia in only two of eight patients, and completion mucosectomy was performed. Dysplasia in ATZ was associated with a preoperative (P = 0.02) or postoperative (P = 0.04) pathologic diagnosis of ulcerative colitis with concurrent dysplasia or cancer. No association (P > 0.05) was found between dysplasia and the following: age, sex, preoperative length of disease, use of a double-stapled versus single-stapled technique, or anastomotic distance from the dentate line. CONCLUSIONS: Incidence of low-grade dysplasia in ATZ was low. Restorative proctocolectomy with total mucosectomy of the anal canal and handsewn IPAA is recommended for patients with preoperative diagnosis of ulcerative colitis and concurrent cancer or dysplasia. Frequent follow-up with biopsies is recommended for patients with incidental finding of cancer or high-grade dysplasia after restorative proctocolectomy and stapled IPAA with preservation of ATZ. For persistent or recurrent low-grade dysplasia, we recommend a completion mucosectomy.

Adult↗

Ulcerative colitis and coexisting colorectal cancer: recurrence rate after restorative proctocolectomy.

BACKGROUND: The association between mucosal ulcerative colitis (MUC) and adenocarcinoma is well established. METHODS: Records of patients who had undergone restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) from 1983 through 1992 were examined. Of these, 604 had MUC and 27 (4.3%) had MUC with coexisting cancer. Patients were surveyed annually for recurrent disease. Pouch function and quality of life were evaluated with a questionnaire and physical examination. RESULTS: The duration of disease was longer (p = 0.001) in patients with cancer (16.1 +/- 8.0 years) than in those without cancer (9.1 +/- 7.1 years), although the mean age at diagnosis of MUC was the same. Of the 27 patients, 20 had colon cancer and seven had rectal cancer. Multicentricity was found in seven (25.9%) patients. Using the TNM staging classification, 14 patients (51.8%) had stage 1 cancer, eight (29.6%) had stage 2, four (14.8%) had stage 3, and one (3.8%) had stage 4. The patient with stage 4 cancer died 5 months after surgery and was excluded from the follow-up analysis. During a mean follow-up time of 4.3 +/- 2.6 years, cancer recurred in two of the remaining 26 patients (7.7%). In one patient, a local recurrence was found 8 months after surgery, and distant metastases were found in the other patient 35 months after surgery. Both recurrences were in patients with colon cancer. Two of the 26 patients died; one death was related to cancer recurrence (3.8%). Pouch function is good to excellent in all surviving patients. CONCLUSIONS: Restorative proctocolectomy for patients with MUC and coexisting colorectal cancer can be performed with a favorable prognosis and function. It is appropriate for curative intent, given that an adequate margin without tumor is obtained.

Adolescent↗

Physical and genetic mapping at the ATA/ATC locus on chromosome 11q22-23.

Genetic heterogeneity in ataxia-telangiectasia (A-T) points to four different genes responsible for this disease. The two major A-T genes, ATA and ATC, were localized by genetic analysis close to each other on chromosome 11q22-23, prompting efforts of positional cloning. Essential steps in positional cloning are long-range cloning of the genomic region of interest, and derivation of highly polymorphic markers that would allow further reduction of the interval carrying the A-T gene. We constructed genomic contigs across the D11S611-D1S424 region harbouring the ATA and ATC genes in yeast artificial chromosome (YAC) vectors. These contigs were used as a fine mapping tool and enabled us to localize along the A-T region, eight microsatellite markers generated randomly by genome mapping centres. In addition, we used specific YAC clones to generate five new microsatellite markers based on polymorphic CA repeats. Recombination mapping based on Israeli A-T families indicates that the ATC gene is distal to the locus D11S1817. Further linkage analysis using these markers is expected to reduce the major A-T locus considerably to a size appropriate for cosmid cloning and identification of transcribed sequences.

Ataxia Telangiectasia↗

Oncogenic osteomalacia induced by schwannoma in a patient with neurofibromatosis.

A 62-year-old woman known to be suffering from Von Recklinghausen disease and osteomalacia was operated on for a pelvic mass. Pathological examination of the excised tumor showed it to be a schwannoma and this tumor was considered to be responsible for the osteomalacia. The return of previously abnormal laboratory data to normal values and the impressive clinical and subjective improvement further support the assumption that the excised schwannoma was responsible for the pathology observed in this patient.

Female↗

Paired STSs amplified from radiation hybrids, and from associated YACs, identify highly polymorphic loci flanking the ataxia telangiectasia locus on chromosome 11q22-23.

The high resolution mapping of the ataxia telangiectasia (A-T) locus on chromosome 11q22-23 requires the generation of new polymorphic markers specifically within the segment of 11q22-23 to which the locus has been assigned. We have made use of a library of Alu-PCR clones, amplified from a radiation reduced somatic cell hybrid containing the relevant chromosome 11 segment, to generate sequence tagged sites (STS) within the 11q22-23 region and have used YAC clones to extend the loci identified by these STSs. The identification of paired polymorphisms (from Alu-PCR and the associated YAC derived clone), which are physically linked, but which show minimal linkage disequilibrium, provides a highly informative haplotype for use in genetic linkage analysis in A-T families. We describe the characterisation of 2 such polymorphic loci, D11S535 and D11S611, which map between existing flanking markers, and which provide additional information on the location of the major A-T locus.

Ataxia Telangiectasia↗

Bilateral localized Castleman disease of the retroperitoneum.

A case report of a 23-year-old patient with abdominal pain was found to have a bilateral, retroperitoneal localized form of Castleman disease. To the best of our knowledge, it is the first report of a bilateral form described in the literature. Surgical excision resulted in the disappearance of symptoms and both masses were found to be of the hyaline type. Follow-up computerized tomography revealed no pathological sequelae.

Adult↗

Ataxia-telangiectasia: linkage analysis in highly inbred Arab and Druze families and differentiation from an ataxia-microcephaly-cataract syndrome.

Ataxia-telangiectasia (A-T) is a progressive autosomal recessive disease featuring neurodegeneration, immunodeficiency, chromosomal instability, radiation sensitivity and a highly increased proneness to cancer. A-T is ethnically widespread and genetically heterogeneous, as indicated by the existence of four complementation groups in this disease. Several "A-T-like" genetic diseases share various clinical and cellular characteristics with A-T. By using linkage analysis to study North American and Turkish A-T families, the ATA (A-T, complementation group A) gene has been mapped to chromosome 11q23. A number of Israeli Arab A-T patients coming from large, highly inbred families were assigned to group A. In one of these families, an additional autosomal recessive disease was identified, characterized by ataxia, hypotonia, microcephaly and bilateral congenital cataracts. In two patients with this syndrome, normal levels of serum immunoglobulins and alpha-fetoprotein, chromosomal stability in peripheral blood lymphocytes and skin fibroblasts, and normal cellular response to treatments with X-rays and the radiomimetic drug neocarzinostatin indicated that this disease does not share, with A-T, any additional features other than ataxia. These tests also showed that another patient in this family, who is also mentally retarded, is affected with both disorders. This conclusion was further supported by linkage analysis with 11q23 markers. Lod scores between A-T and these markers, cumulated over three large Arab families, were significant and confirmed the localization of the ATA gene to 11q23. However, another Druze family unassigned to a specific complementation group, showed several recombinants between A-T and the same markers, leaving the localization of the A-T gene in this family open.

Ataxia↗

The ATC (ataxia-telangiectasia complementation group C) locus localizes to 11q22-q23.

The multisystem autosomal recessive disease ataxia-telangiectasia (A-T) is determined by several genes, as evidenced by the existence of four complementation groups in this disorder. Using linkage analysis, the ATA (A-T complementation group A) gene was previously localized to chromosome 11, region q22-q23. Analysis of the segregation of RFLP markers from this region in a Jewish-Moroccan family assigned to group C indicates that the ATC (A-T complementation group C) gene localizes to chromosome 11q22-q23 as well.

Ataxia Telangiectasia↗

Prospects for the chemoprevention of breast cancer.

Breast cancer is by far the most common type of cancer in women accounting for 20% of all new cases. It is estimated that 1 in 12 women will develop breast cancer at some time in their life. Each year in the UK, 24,500 women are newly diagnosed with breast cancer and 15,000 women die from it. The incidence rates rise from less than 10 per 100,000 women aged under 30 years to 300 per 100,000 in women aged over 85 years. The seriousness of the problem is emphasized by the fact that for women aged 35-54 years, breast cancer is the commonest single cause of all death. Both the incidence and the mortality have slightly increased in recent years, although mainly in the older age groups. There has been a slight decrease in the mortality rates for women aged 15-44 years over the last 35 years, but in all the older age groups there have been increases.

Adolescent↗

Localization of an ataxia-telangiectasia locus to a 3-cM interval on chromosome 11q23: linkage analysis of 111 families by an international consortium.

Linkage of at least two complementation groups of ataxia-telangiectasia (AT) to the chromosomal region 11q23 is now well established. We provide here an 18-point map of the surrounding genomic region, derived from linkage analysis of 40 CEPH families. On the basis of this map, 111 AT families from Turkey, Israel, England, Italy, and the United States were analyzed, localizing the AT gene(s) to an 8-cM sex-averaged interval between the markers STMY and D11S132/NCAM. A new Monte Carlo method for computing approximate location scores estimates this location as being at least 10(8) times more likely than the next most likely interval, with a support interval midway between STMY and D11S132 that is either 5.2 cM (sex-averaged and conservatively based on 3 lod scores from the maximum-location score) or 2.8 cM (male specific, based on a 2.72:1 interval-specific female-to-male distance ratio.

Ataxia Telangiectasia↗

B lymphocyte changes induced by peri-operative blood transfusions and surgery in patients with colorectal cancer.

Seventy patients with Duke's C adenocarcinoma scheduled to undergo surgery were divided into two groups, those who received no peri-operative transfusion (Group I, 26 patients) and those who received an average of 2.1 units of packed red blood cells per person peri-operatively (Group II, 44 patients). Immunological parameters were tested 1 week before and 1 and 5 weeks after surgery in order to determine the influence of the transfusion of these parameters. Comparison of the mean values obtained before operation with those obtained one week post-operatively revealed a significant change in the number of B cells (P = 0.014), with a decrease in Group I and an increase in Group II, which was seen to persist for the mean values obtained 5 weeks after surgery. The higher rates of recurrence and the lower rates of survival reported in patients who received transfusion may be related to an as yet unidentified role of B cells or a subpopulation in the immune system, manifested in the suppression of activity of those components responsible for destroying micrometastases. In relation to the site of the tumor no definite conclusions can yet be drawn as to the prognostic importance of our findings concerning the immunological parameters.

Adenocarcinoma↗

Massive haemoperitoneum complicating metastasis in the liver.

The rare phenomenon of gross intra-abdominal bleeding due to hepatic metastasis was seen in a young male who a short time before had undergone orchiectomy because of embryonal cell carcinoma. Following laparotomy, 4 liters of fresh blood were drained from the peritoneal cavity and the left lobe of the liver, containing a single large metastasis, was removed. It is stressed that when no other cause of such haemorrhage can be found in a patient known to have had malignancy, the possibility of bleeding from a metastasis should be considered and appropriate measures taken.

Adult↗