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A Amiel

Publications and source records attributed to A Amiel.

At least 55 records · Page 3Linked to original sources
PubMed1997

Asynchronous replication of p53 and 21q22 loci in chronic lymphocytic leukemia.

In this study, in order to evaluate the replication pattern and the cell cycle dynamics of normal and malignant cells from patients with chronic lymphocytic leukemia, we applied the FISH technique with the p53 gene. Asynchrony was determined by the presence of one single and one set of double dots in the same cell. The rate of asynchronous replication was significantly higher in malignant cells than in normal cells (a mean of 28 vs 13, respectively, P = 0.023). There were proportionately more cells with two single dots among the normal cells (P = 0.0047). These results probably reflect the changes in gene replication and cell cycle progression that occur in malignant cells.

Cell Cycle↗
PubMed1997

Monoallelic p53 deletion in chronic lymphocytic leukemia detected by interphase cytogenetics.

Chromosomal aberrations can be detected in 50% of patients with chronic lymphocytic leukemia (CLL). A role for tumor suppressor genes in the genesis of lymphoid tumors has been reported. In B-CLL, p53 gene mutations were found in 10-15% of the patients. We used fluorescence in situ hybridization (FISH) to detect p53 deletion in B-CLL. We also correlated the cytogenetic findings with the clinical course. In situ hybridization to interphase nuclei showed monallelic p53 deletion in 6 of 23 patients (26%). The percentage of cells with one p53 signal ranged from 12 to 100. A statistically significant correlation between p53 deletion and progression of CLL was demonstrated. We conclude that FISH is a sensitive and reliable method to detect deletion of specific genes (i.e., p53) in CLL. The finding of p53 deletion is associated with disease progression.

Aged↗
PubMed1997

Elevated hCG as an isolated finding during the second trimester biochemical screen: genetic, ultrasonic, and perinatal significance.

This study was undertaken in an attempt to determine the significance of elevated maternal serum human chorionic gonadotropin (MShCG), in the presence of an otherwise normal screen with respect to fetal malformations, chromosomal aberrations, and pregnancy outcome. Targeted ultrasound findings and perinatal outcome of 298 women in whom serum hCG was > or = 2.5 MOM and who were screen-negative for Down syndrome (the study group) were compared with a control group of 229 women in whom serum hCG as well as the other parameters were within the normal range. Genetic amniocentesis was performed in 125 women from the study group. Ultrasonically detected malformations were significantly more frequent among the study group (12 vs. 1, P = 0.01). Pregnancy complications were similar in the two groups, with the exception of pre-eclampsia-toxaemia, which was significantly more frequent in the study group (5 vs. 0, P = 0.02). There was one case of an abnormal karyotype (47,XXY). Although genetic amniocentesis does not appear warranted, isolated elevated MShCG levels during the second trimester screening was associated with an increased risk of fetal anomalies detected by ultrasound and of toxaemia of pregnancy.

Adult↗
PubMed1996

Are all phenotypically-normal Turner syndrome fetuses mosaics?

Cytogenetic and fluorescent in situ hybridization (FISH) studies were performed on several formalin-fixed tissues obtained from four fetuses diagnosed at amniocentesis as 45,XO-Turner syndrome. Three of the four were phenotypically normal and one had malformations. The three phenotypically normal cases were found to have an additional normal cell line, which may explain their ability to survive, at least to the time of pregnancy termination well into the second trimester. The abnormal 45,XO fetus was not found to be mosaic in all of the tissues examined. In 45,XO cases in which no malformation is detected, the possibility of mosaicism should be raised and thus the counselling should be modified accordingly.

Cell Count↗
PubMed1996

Synergistic effects of interleukin-11 with other growth factors on the expansion of hematopoietic progenitors from normal individuals and chronic myeloid leukemia patients resistant to treatment with cytosine arabinoside or eilatin.

Interleukin-11 (IL-11) is a novel cytokine that has been shown to stimulate human hematopoietic progenitors including the CD34+ CD33- DR- early progenitors. IL-11 has little effect on its own but it synergizes with other hematopoietic growth factors. We investigated the recovery of human myeloid progenitors incubated with IL-11 alone or in combination with other cytokines, including stem cell factor (SCF), interleukin-3 (IL-3) and granulocyte macrophage colony-stimulating factor (GM-CSF) following their in vitro treatment with ARA-C (10(-9) M) or Eilatin (10(-7) M). IL-11 in combination with IL-3 and GM-CSF markedly increased CFU-C colony growth pre- and post-ARA-C or Eilatin incubation from CML and normal individual bone marrow (BM) cells. Similarly, IL-11 alone or in combination with other cytokines increased cell recovery following 7-day suspension culture. A decrease in BCR/ABL fusion product was observed (by FISH analysis) after incubation of BM cells from CML patients in liquid culture for 7 days with 10(-9) M ARA-C or 10(-7) M Eilatin in the presence of IL-11 alone or in combination with other cytokines. These results indicate that following cytoreductive therapy IL-11 may enhance to a greater extent the growth of normal myeloid progenitors than the malignant clone and may, therefore, be of clinical importance for CML patients treated with chemotherapeutic agents.

Animals↗
PubMed1996

Genetic diagnosis from formalin-fixed fetal tissue using FISH: a new tool for genetic counseling in subsequent pregnancies.

We evaluated the feasibility of retrospective genetic testing for numerical chromosomal aberrations by applying the FISH technique to formalin-fixed fetal tissue. Fetal tissue from 10 old cases with known aneuploidy and from 13 cases with known fetal malformations, were tested with specific DNA probes for pericentromeric repeat regions of chromosomes 13/21, 18, X and Y. FISH diagnosis concurred with karyotype in all nine cases with sufficient cells. Numerical aberration was diagnosed in six out of 13 cases with fetal malformations.

Aneuploidy↗
PubMed1996

Trisomies 9 and 8 detected by fluorescence in situ hybridization in patients with systemic mastocytosis.

BACKGROUND: Systemic mastocytosis is a rare disease characterized by proliferation of mast cells in one or more organs. The origin of the mast cells is still debated, although it has been recently shown that they derive from CD34+ hematopoietic progenitors. Some clinical and in vitro studies have suggested a possible link between myeloproliferative disorders and systemic mast cell disease. OBJECTIVE: This study was designed to further evaluate the association between systemic mast cell disease and other hematologic disorders by means of conventional cytogenetic analysis and fluorescent in situ hybridization. METHODS: We used cytogenetic analysis and fluorescent in situ hybridization with probes to chromosomes 8 and 9 in six patients with systemic mast cell disease. RESULTS: Fluorescent in situ hybridization helped to identify five patients with trisomy 9 and one with trisomy 8. In contrast, chromosomal analysis demonstrated an abnormal karyotype (45,XO/46,XY) in only one patient. CONCLUSION: The association between myeloproliferation disorders and systemic mast cell disease may be explained by the finding that trisomy 9 and trisomy 8 are common in both disorders. A trisomy was detected in all of the patients in our small group compared with nearly 40% of previously reported patients with myeloproliferative disorders. FISH is more sensitive than conventional cytogenetics in detecting these aberrations.

Adult↗
PubMed1996

The detection of trisomies 8 and 9 in patients with essential thrombocytosis by fluorescence in situ hybridization.

Essential thrombocytosis (ET) is a clonal, chronic myeloproliferative disorder (MPD) originating from a multipotent stem cell. To date no specific cytogenetic marker has been found in ET. It was recently reported that chromosomal aberrations have been detected by fluorescence in situ hybridization (FISH) in patients with normal karyotypes or nonanalyzable metaphases. Therefore, we evaluated whether trisomies 8 and 9, which are commonly found in MPDs, can be detected in ET by FISH and compared the results with chromosome analysis. Peripheral blood mononuclear cells of patients with essential thrombocytosis were studied by classical chromosome banding and by FISH. We used biotin labeled alpha satellite of chromosome 8 and biotin labeled beta satellite of chromosome 9 as probes for the FISH studies. FISH detected 5 patients with trisomy 8 and 5 with trisomy 9 of the 18 patients evaluated. No trisomy was found by cytogenetic studies. The trisomies were detected by FISH in only a minority of the cells. No correlation was found between the presence of a trisomy and clinical characteristics. FISH is a sensitive method for the detection of trisomies 8 and 9 in patients with ET. The common finding of these chromosomal aberrations in MPD suggests that genes associated with myeloid proliferation are located on these chromosomes. Standardization of interphase cytogenetics is needed before this technique can be accepted for routine use in the clinic.

Adult↗
PubMed1996

Fluorescent in situ hybridization (FISH) for the detection of trisomy 8 in acute myeloblastic leukemia.

The karyotype of acute myeloid leukemia (AML) blasts has a major prognostic importance. However conventional cytogenetic studies of AML patients may fail to reveal chromosome abnormalities. Trisomy 8 is a common numerical abnormality in all AML subtypes. We evaluated the role of fluorescent in situ hybridization (FISH) in the detection of trisomy 8 in de-novo AML, and compared the results to chromosome analysis in some patients. Cytogenetic studies were performed in 9 of 12 patients. In three patients no metaphases were obtained. Of the remaining six, trisomy 8 was only detected in the metaphases of 1 patient. In contrast, 4 patients showed +8 with FISH and one had a borderline value. We conclude that FISH is a rapid and sensitive method to detect numerical aberrations in AML. In the future larger prospective studies should explore the biological and clinical application of the FISH method in different hematological malignancies.

Adult↗
PubMed1995

Uterine cavity lavage: adding FISH to conventional cytogenetics for embryonic sexing and diagnosing common chromosomal aberrations.

This study was undertaken to examine the efficacy for early prenatal diagnosis of uterine cavity lavage at the level of the internal os and to assess the rate of maternal contamination. In phase I, uterine cavity lavage was performed in 38 women scheduled for pregnancy termination between 6 and 12 weeks. In addition to short- and long-term cultures, one-colour FISH (fluorescence in situ hybridization) with Y and X probes was used for fetal sexing. Two-colour FISH was used in all known male fetuses for the assessment of maternal contamination. In phase II, lavage was performed on 16 women. Fetal sex was diagnosed with direct labelled X and Y probes and common numerical chromosomal aberration was attempted with 18 and 21 direct labelled probes. Fetal sexing was successful in all cases in phases I and II. Out of 34 patients in which tissue was obtained, only FISH was done in six. Long-term cell cultures were successful in the other 28 cases, but complete karyotyping in 19 (56 per cent). No chromosomal aberration was found with the direct labelled probes 18 and 21 in FISH. Maternal contamination was assessed to be 5-10 per cent. This simple and easy-to-master technique is very effective in obtaining fetal cells early in pregnancy for genetic diagnosis, especially by FISH. However, the safety of the procedure must be tested in ongoing pregnancies.

Adolescent↗
PubMed1995

Amniocentesis rate and the detection of Down syndrome and other chromosomal anomalies in Israel.

We investigated the contribution of different screening criteria to the prenatal detection of Down syndrome (DS) as well as other chromosomal anomalies in the Jewish population in Israel during 1990 and 1992. There was a significant decrease (P < 0.03) in the incidence of DS live-births during 1992 (40:78 442) compared with 1990 (69:73 751) which paralleled a marked increase in total prenatal testing and in DS cases detected prenatally. Private laboratories, which perform amniocenteses mostly for women with a low risk of DS and without genetic counselling, had a significantly lower detection rate (1:917) compared with that of the genetic institutes, which following genetic counselling test both women > or = 37 years of age (1:91) and women younger than 37 years (1:113). The detection of chromosomal anomalies other than DS was less affected by the reason for amniocentesis. Amniocentesis indicated by maternal serum marker screening of women younger than 37 years identified a greater number of chromosomal anomalies other than DS than amniocentesis based on age (> or = 37 years) alone (111:9604 versus 94:9810; P < 0.06). Prenatal detection of DS is most effective when the indication for amniocentesis follows genetic counselling. The increasing use of maternal serum marker screening leads to a significant improvement in the positive detection rate of chromosomal anomalies other than DS in young women.

Adult↗
PubMed1995

Fluorescent in-situ hybridization (FISH) as an aid to marker chromosome identification in prenatal diagnosis.

Five cases of supernumerary marker chromosomes were identified in prenatal diagnosis as derived from chromosomes 18, X, and Y. One unexpected finding was in a case where the PCR was positive for the SRY gene while fluorescence in situ hybridization was positive for two X centromeres. In another case with an X derived supernumerary marker the newborn was phenotypically normal. Two women with fetal mar(18) and mar(Xp) decided to terminate the pregnancy. The fifth pregnancy had a karyotype of 46,XX,-15,+der(15)t(Y:15)(q11,23;p13). A phenotypically normal girl was born at term.

Adult↗
PubMed1995

Fluorescence in situ hybridization for the detection of trisomies 8 and 9 in polycythemia vera.

Trisomies 8 and 9 are the most common numerical chromosome abnormalities in polycythemia vera (PCV). Their role in the pathogenesis of the disease is unclear, however, as is their diagnostic or prognostic value. We evaluated fluorescent in situ hybridization as compared to chromosome analysis for the detection of trisomies 8 or 9 in peripheral blood cells of PCV patients. We demonstrated that FISH is a more sensitive method for the detection of the abnormalities. A positive correlation between the duration of the disease and trisomy 9 was found. FISH is a sensitive, convenient, and rapid method for the diagnosis and follow-up of chromosome aberrations in patients with PCV. The application of FISH to a larger cohort of patients may provide valuable information regarding the role of the chromosomal aberrations in the initiation and progression of this disease.

Adolescent↗
PubMed1995

Fluorescence in situ hybridization (FISH) for retrospective detection of trisomies 3 and 7 in multiple myeloma.

The malignant plasma cells of multiple myeloma (MM) have a low proliferative activity and therefore cytogenetic studies of the disease have been severely limited. We evaluated the role of fluorescence in situ hybridization (FISH) in the detection of numerical chromosomal abnormalities in early stages of myeloma and the applicability of the method to stored archival slides. Old air-dried bone marrow smears from 15 myeloma patients obtained at presentation were probed with alpha satellite DNA sequences to chromosomes 3 and 7. Numerical chromosome aberrations were found in eight (53%) of the patients, including six (of 12) with trisomy 7, and two (of eight) with trisomy 3. This study demonstrates that FISH is a sensitive method for the detection of numerical aberrations in myeloma and for the study of old slides for retrospective analysis.

Aged↗
PubMed1995

The BCL-1, BCL-2, and BCL-3 oncogenes are involved in chronic lymphocytic leukemia. Detection by fluorescence in situ hybridization.

The putative oncogenes BCL-1, BCL-2, and BCL-3 are commonly rearranged by translocations to the immunoglobulin genes in B-cell malignancies. However, Southern blotting rarely detected their involvement in chronic lymphocytic leukemia (CLL). This discrepancy could stem from some unique features of the oncogenesis of CLL or be due to shortcomings of Southern blotting. We have therefore evaluated the role of fluorescence in situ hybridization (FISH) in the detection of these oncogenes in CLL. Twenty consecutive CLL patients were studied by FISH for the detection of BCL-1, BCL-2, or BCL-3 rearrangement and for the presence of trisomy 12. Selected patients were also evaluated by classical cytogenetic techniques and by Southern blot analysis. Juxtaposition of JH and BCL-1 was demonstrated in 10 (50%), BCL-2 in three (15%), and BCL-3 in four (20%) of the patients. Trisomy 12 was detected by FISH in 11 (55%) patients. The coexistence of trisomy 12 and translocation of the BCL-1 oncogene was common. Three of the patients had chromosomal aberrations compatible with those detected by FISH. In contrast, in none of the five patients selected by their positive FISH findings was a rearrangement demonstrated by Southern blotting. We conclude that FISH is a sensitive method for the detection of oncogene involvement in CLL. Mainly BCL-1, but also BCL-2 and BCL-3, are commonly translocated to the immunoglobulin heavy chain locus on chromosome 14. These translocations are often associated with trisomy 12. These findings indicate that the BCL oncogenes are commonly involved in CLL and lend support to the multi-hit theory of cancer development.

Aged↗
PubMed1995

Monoclonal lymphocyte proliferation and bcl-2 rearrangement in essential mixed cryoglobulinaemia.

A patient with essential mixed cryoglobulinaemia (EMC) type II and hepatitis C virus (HCV) infection, in whom immunophenotypic and genotypic studies demonstrated a clonal proliferation of B lymphocytes, is described. Fluorescent in situ hybridization with probes to Ig heavy chain gene and to the oncogene bcl-2 demonstrated a translocation of bcl-2 to the immunoglobulin heavy chain locus on chromosome 14. A sharp rise in the level of the monoclonal IgM was associated with a second genetic aberration [t(8:22) (q24:q11)]. No other clinical evidence of disease progression could be demonstrated. Low grade lymphoproliferative disorder with typical cytogenetic abnormalities developed on the background of EMC and HCV. Clinical progression was associated with a second genetic abnormality involving the myc oncogene. It is possible that HCV chronic infection may indirectly influence oncogenes associated with lymphoma.

Adult↗
PubMed1995

[Regression towards the mean and repeated echocardiographic measurements of the left ventricular mass].

The selection of a group of patients based on a high value of a clinical or biological parameter leads to the finding of a tendency to a reduction of this value when remeasured, known as "regression towards the mean". The amplitude of this phenomenon is greater when the selected subjects are far from normal values and the intra-individual variability of the parameter under consideration is very high. Measurement of left ventricular mass is very affected by this statistical phenomenon. The authors undertook a prospective study to analyse the components of variability of repeated echocardiographic measurements of left ventricular mass and to quantify the expected effect of regression towards the mean in the follow-up of patients with left ventricular hypertrophy. Twenty-five randomly chosen subjects underwent 2 echocardiographic examinations at 2 week intervals: at each visit, the patient had two recordings and each recording was measured twice by the same "blinded" operator. Variance analysis showed intra-individual variability represented 30% of total variability, comprising only 2% for the measurements and 28% for the recordings and the visits. The importance of regression towards the mean was calculated with respect to the initial value of the left ventricular mass index: for example, when the left ventricular mass index was 150 g/m2, a spontaneous regression of 18 g/m2 can be expected at the next measurement. This phenomenon should be taken into consideration in the interpretation of longitudinal echocardiographic studies.

Adolescent↗