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Y Ziv

Publications and source records attributed to Y Ziv.

At least 19 recordsLinked to original sources
PubMed1992

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↗
PubMed1991

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↗
PubMed1991

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↗
PubMed1991

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↗
PubMed1991

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↗
PubMed1990

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↗
PubMed1990

Genetic mapping of X-linked albinism-deafness syndrome (ADFN) to Xq26.3-q27.I.

X-linked albinism-deafness syndrome (ADFN) was described in one Israeli Jewish family and is characterized by congenital nerve deafness and piebaldness. The ADFN mutation probably affects the migration of neural crest-derived precursors of the melanocytes. As a first step toward identifying the ADFN gene, a linkage study was performed to localize the disease locus on the X chromosome. The family was found to be informative for 11 of 107 RFLPs along the X, and two-point analysis showed four of them--factor 9 (F9), DXS91, DXS37, and DNF1--to have definite or suggestive linkage with ADFN. Multipoint linkage analysis indicated two possible orders within this cluster of loci, neither of which was preferable. In both orders F9 was the most distal, and the best estimate for the location of ADFN was between F9 and the next proximal marker (8.6 cM from F9 [Z = 8.1] or 8.3 cM from F9 [Z = 7.9]). These results suggest that the ADFN is at Xq26.3-q27.1. Disagreement between our data and previous localization of DXS91 at Xq11-q13 was resolved by hybridization of the probe pXG-17, which detects the DXS91 locus, to a panel of somatic cell hybrids containing different portions of the X chromosome. This experiment showed that this locus is definitely at Xq24-q26. Together with the linkage data, our results place DXS91 at Xq26 and underscore the importance of using more than one mapping method for the localization of molecular probes.

Albinism↗
PubMed1989

Cellular and molecular characteristics of an immortalized ataxia-telangiectasia (group AB) cell line.

Ataxia-telangiectasia (A-T) is a multisystem hereditary disease featuring neurodegeneration, immunodeficiency, extreme cancer proneness, chromosomal instability, and radiosensitivity. A-T is found in many ethnic groups, and is genetically heterogeneous: four complementation groups have been identified in A-T so far. Attempts to isolate the A-T gene are based in part on gene transfer experiments, using permanent A-T fibroblast lines, obtained by transformation with SV40. "Immortalization" of A-T primary diploid fibroblasts using SV40 is difficult, possibly because of the chromosomal instability of these cells. The number of currently available permanent A-T fibroblast lines is small, and not all of them have been assigned to specific complementation groups. Using the assay of X-ray induced inhibition of DNA synthesis, we have assigned the A-T strain AT22IJE to complementation group AB. Origin-defective SV40 was used to transfect these cells, and one transformant (AT22IJE-T), which survived crisis, was found to have the typical characteristics of permanent cell lines obtained in this way. "In-gel renaturation" analysis did not show any DNA amplification of high degree in AT22IJE-T. Cytogenetic analysis showed considerable chromosomal instability in the new cell line, and medium conditioned by these cells contained the clastogenic activity which is characteristic of the parental strain as well. Other parameters of the "cellular A-T phenotype" have also been retained in the immortalized cells: hypersensitivity to the lethal effects of X-rays and neocarzinostatin, as well as "radioresistant" DNA synthesis. However, the sensitivity of AT22IJE-T to both DNA-damaging agents is less pronounced than that of the parental cells. The capacity of the cells for uptake of foreign DNA was tested by introducing into them the plasmid pRSVneo, using three different transfection methods. Satisfactory frequency of G418-resistant transfectants (0.66%) was achieved using a protocol recently published by Chen and Okayama (Mol. Cell Biol., 7: 2745-2752, 1987), which was found to be superior to the traditional calcium phosphate transfection method and to the polybrene-based method.

Ataxia Telangiectasia↗
PubMed1989

G2 chromosomal radiosensitivity in families with ataxia-telangiectasia.

Ataxia-telangiectasia (A-T) is an autosomal recessive disease involving chromosomal instability, susceptibility to cancer and X-ray hypersensitivity. The latter two features are expressed to a limited extent in the heterozygous carriers of A-T mutations. Although fibroblast lines from A-T heterozygotes clearly show increased susceptibility to the lethal effect of X-irradiation, the difference in post-irradiation survival between cell lines and normal controls is not always large enough to allow the use of X-ray sensitivity as a laboratory assay for carrier detection in A-T. Recently, we have shown in a blind study, that the extent of chromatid damage induced in the G2 phase of the cell cycle by moderate doses of X-rays is markedly higher in A-T heterozygous cells than in normal controls. We have now applied this test to 6 additional obligatory heterozygotes and 24 individuals with different risks of being A-T carriers, from three Israeli A-T families. All 6 cell lines from the obligatory heterozygotes showed the typical hypersensitivity to the clastogenic action of X-rays in G2; of the 24 cell lines with unknown A-T genotype, 16 showed the same hypersensitivity, and 8 responded in a normal way. The proportion of cell lines showing the "A-T-heterozygous phenotype" was in accord with the expected value, based on Mendelian chance calculations. Since these observations were made, a daughter of two hypersensitive parents in one of these families has been diagnosed as having A-T. This confirmed the presumed A-T heterozygosity of the parents, as indicated by the laboratory assay.

Ataxia Telangiectasia↗
PubMed1989

Ataxia-telangiectasia: a variant with altered in vitro phenotype of fibroblast cells.

The clinical and cellular phenotype of ataxia telangiectasia (AT) has been extensively documented in numerous patients of different ethnic groups and is characterized by several specific laboratory hallmarks, such as chromosomal instability, profound radiosensitivity and radioresistant DNA synthesis. Several recent reports have, however, shown variations on this theme. This article describes 2 Turkish siblings with AT, who showed a typical but somewhat more prolonged clinical course of the disease and altered characteristics of fibroblast cells, compared to the 'classical' AT cellular phenotype. Fibroblast strains derived from these patients showed a normal cellular life span, moderate degrees of chromosomal instability and sensitivity to the lethal effects of X-rays and neocarzinostatin, and lack of radioresistant DNA synthesis. A compilation of the literature on 'AT variants' and 'AT-like' syndromes shows that in addition to the internal variability of AT, this disease occupies a limited segment within a large spectrum of clinical and cellular features, which are common to a variety of syndromes. Each of these syndromes covers a different segment in this spectrum. The genetic basis of this family of disorders might be complex.

Ataxia Telangiectasia↗
PubMed1989

Segmental portal hypertension and polycythemia vera.

A patient known to have polycythemia vera developed recurrent melena and was found to have bleeding gastroesophageal varices. Selective superior mesenteric angiography suggested splenic vein thrombosis. Splenectomy led to the disappearance of the varices with no subsequent recurrence of bleeding. We believe this to be the first fully described case of polycythemia vera associated with segmental portal hypertension, and propose that polycythemia vera patients may develop "silent" segmental portal hypertension and that this should be taken into consideration when treating them.

Humans↗
PubMed1989

Clinical implications of anatomic variations of the splenic artery.

An aberrant course of the proximal splenic artery was observed in nine of 26 adult cadavers dissected for mapping of the lesser omentum. Such an aberrant course makes the artery vulnerable to iatrogenic injury. In view of this relatively high prevalence of splenic artery aberration, it is suggested that surgeons operating in the area of the lesser omentum should keep in mind the possibility of its occurrence and the dangers that it may present.

Adult↗
PubMed1988

Local recurrence after low anterior resection using the EEA stapling device.

Fifty-five patients underwent curative stapled low anterior resection for rectal adenocarcinomas located 5 to 15 cm from the anal verge. Two patients (3.7 percent) died postoperatively. The mean follow-up for the remaining 53 patients was 40 months. Local recurrence was diagnosed in 17 patients (32 percent), in most (88 percent) within the first two years after surgery. Most local recurrences appeared in patients classified as Dukes' C1 and C2 but, surprisingly, no significant difference was found between rectal tumors of high and low location as regards recurrence. The high rate of recurrence in this series may be attributable to the large number of patients with advanced tumors, and poorly differentiated carcinoma, or both.

Adenocarcinoma↗