1/1493. Increased sister chromatid exchange in bone marrow and blood cells from Bloom's syndrome.Bone-marrow cells from a patient with Bloom's syndrome cultured for 48 h in the presence of BudR exhibited a striking increase in the number of sister chromatid exchanges (SCEs) in comparison to that in the marrow cells of a patient with treated polycythemia vera (PV). Thus, it appears that an increased incidence of SCE in Bloom's syndrome occurs in various differentiated types of cells, not just blood lymphocytes, and constitutes the syndrome's most characteristic cytogenetic feature. In contrast, the incidence of SCE was not increased in marrow cells and lymphocytes of the particular PV patient studied here, whose cells did exhibit increased numbers of chromatid and chromosome gaps and breaks, presumably as result of the patient's earlier treatment. An increased frequency of SCE was demonstrated in Bloom's syndrome lymphocytes using both a technique based on BudR incorporation and one based on labeling with tritated deoxycytidine. This observation constitutes evidence against the increase of SCE being due to an unusual reaction to BudR. By conventional cytogenetic techniques, chromosome instability, including chromatid and chromosome breaks, but no homologous chromatid interchanges were also recognized in Bloom's syndrome bone-marrow cells incubated in vitro (without BudR) for either 1.k or 16 h. This observation points to the existence of chromosome instability in vivo.- - - - - - - - - - ranking = 1keywords = chromosome (Clic here for more details about this article) |
2/1493. Ring chromosome 14 complicated with complex partial seizures and hypoplastic corpus callosum.A Japanese male with mosaicism of ring chromosome 14 and chromosome 14 monosomy is described. He demonstrated the characteristic morphologic features of ring chromosome 14, in addition to mental retardation and epileptic seizures. Clusters of complex partial seizures, one of which originated in the left frontocentral region on electroencephalographic monitoring, were evident. His seizures responded to phenobarbital, and his mental and motor development was only mildly retarded. magnetic resonance imaging revealed a hypoplastic corpus callosum, previously unknown in association with this syndrome.- - - - - - - - - - ranking = 1.80267995446keywords = chromosome, ring chromosome, ring (Clic here for more details about this article) |
3/1493. Partial monosomy and partial trisomy 18 in two offspring of carrier of pericentric inversion of chromosome 18.A pericentric inversion of chromosome 18 is described in the mother of a patient with clinical diagnosis of 18q--syndrome. The propositus' chromosome complement includes the recombinant 18 with deficiency of the distal one-third of the long arm and duplication of the terminal segment of the short arm. The propositus' sister carrier the recombinant 18 with a duplication of the distal one-third of the long arm and a deficiency of the terminal segment of the short arm. The relative length of the inverted segment represents about 60% of the total chromosome 18 length. The probability of recombinant formation following the occurrence of a chiasma within the inverted segment is predicted to be high.- - - - - - - - - - ranking = 1.7515572362106keywords = chromosome, ring (Clic here for more details about this article) |
4/1493. Importance of basophilia in haematopoietic disorders.To the significance of basophilia in haematopoietic disorders, six draw attention to cases have been analyzed. Associated diseases included acute myelogenous leukaemia (AML-M2, M3, M4, and M6), refractory anaemia with excess of blasts (RAEB) and RAEB in transformation (RAEB-T). Two AML cases (M2, M6) were preceeded by myelodysplastic syndromes (MDS). All patients showed greater than 3% basophilia in peripheral blood and bone marrow. basophils were identified successfully by metachromatic staining with toluidine blue in all cases. Three patients (M3, M4, RAEB) presented with lymphadenopathy, suggesting an association with extramedullary involvement. Neutrophil alkaline phosphatase (NAP) activity was significantly reduced in four patients with AML (M2, M3, M4) and RAEB-T. The clinical course was generally unfavourable characterized by short remission duration or disease progression except for the patient with RAEB. Haemorrhage was the main cause of death rather than infection. cytogenetic analysis revealed unique abnormalities involving chromosomes 3q21, 5q31, and 17q11 where the genes for some haematopoietic growth factors or their receptors are located, in addition to t(6;9) and t(15;17).- - - - - - - - - - ranking = 0.25keywords = chromosome (Clic here for more details about this article) |
5/1493. Extra euchromatic band in the qh region of chromosome 9.Chromosomal analysis of amniotic cell culture revealed an extra euchromatic band in the variable heterochromatin region 9q12. cytogenetic analysis of the fetus was compared with the chromosomes of the parents. Using different cytogenetic banding techniques and fluorescence in situ hybridization with specific dna probes, the structural rearrangements involved were considered. The very rare variant proved to be familial. Demonstrating the inheritance of a normal individual supports the interpretation of the prenatal analysis of chromosome 9 as a variant without clinical relevance for the fetus.- - - - - - - - - - ranking = 1.5keywords = chromosome (Clic here for more details about this article) |
6/1493. Progressive dystonia in a child with chromosome 18p deletion, treated with intrathecal baclofen.We report a case of dystonia with a partial deletion of the short arm (p) of chromosome 18 and androgen insensitivity. Neurologic findings in the 18p syndrome are reported to include mental retardation, seizures, incoordination, tremor, and chorea. A 15-year-old girl with a denovo 18p deletion [karyotype 46, XY, del (18)(p11.1)] developed progressive asymmetric dystonia. She had oromotor apraxia and partial expressive aphasia since childhood, and she was able to partially communicate through elementary sign language. At the age of 15 years, she developed subacute and progressive choreic movements of the right arm, severe dystonic posturing of the left arm, and spastic dystonia in both legs. Her response to parenteral or oral benzodiazepines, oral trihexyphenidyl, benztropine mesylate, baclofen, and L-dopa were brief and inadequate. The response to intrathecal baclofen has been sustained over 18 months. In all likelihood, the 18p deletion syndrome affecting this patient is significant in the pathogenesis of her acquired dystonia. Chronic intrathecal baclofen therapy via pump has been effective in this case and should be considered as a treatment modality in carefully selected patients with dystonia.- - - - - - - - - - ranking = 1.2503893090526keywords = chromosome, ring (Clic here for more details about this article) |
7/1493. persistent hyperplastic primary vitreous with retinal tumor in tuberous sclerosis: report of a case including tumoral immunohistochemistry and cytogenetic analyses.OBJECTIVE: The authors describe an ocular lesion combining the characteristics of persistent hyperplastic primary vitreous (PHPV) and a retinal tumor in an infant with tuberous sclerosis complex (TSC). STUDY DESIGN: Case report. methods: immunohistochemistry and cytogenetic studies were performed on TSC cells from an intraocular tumor in a 6-week-old infant. RESULTS: Histopathologic examination showed a thick fibrovascular membrane between the aspect of the lens and the astrocytic component of the mass. glial fibrillary acidic protein (GFAP) showed a variable intracytoplasmic reaction in the astrocytic proliferation, involving approximately 50% of the cells. Tissue culture studies showed a fairly rapid proliferation of fusiform cells, consistent with bipolar astrocytic cells. Cytogenetic studies showed one abnormal clone consisting of three hyperdiploid cells with a loss of chromosome 9 and a gain of chromosomes 6 and 12. CONCLUSION: The atypical localization of the retinal tumor could be explained by the fact that it was trapped during its proliferation by the retinal detachment associated with the PHPV.- - - - - - - - - - ranking = 0.50038930905265keywords = chromosome, ring (Clic here for more details about this article) |
8/1493. Indeterminate-cell histiocytosis: immunophenotypic and cytogenetic findings in an infant.BACKGROUND: The authors report the immunohistochemical, ultrastructural, and cytogenetic findings in a case of malignant histiocytic proliferation in an infant. PROCEDURE: The patient presented initially with bone lesions without skin or systemic involvement. Multiple biopsies were studied extensively by immunohistochemistry and electron microscopy. Cytogenetic studies of cell cultures supplemented with granulocyte-monocyte colony stimulating factor (GM-CSF) were also performed. RESULTS: Morphologically, the cells resembled langerhans cells, although with greater pleomorphism, as evinced by cells with usual polylobated nuclei. These cells expressed markers for macrophages and antigen presenting cells and were CD1a- and S-100-positive, but lacked Birbeck granules. The cells grown in culture supplemented with GM-CSF showed a unique combination of numerical and structural abnormalities affecting chromosomes 1, 6, 8, and 10. The disease followed a malignant course leading to the patient's demise despite aggressive chemotherapy and bone marrow transplant. CONCLUSIONS: The findings suggest a malignant hematopoietic stem-cell neoplasm with a capacity for macrophage or dendritic-cell differentiation. Morphology and immunophenotypic features place this neoplasm within the group recently conceptualized as indeterminate-cell histiocytosis.- - - - - - - - - - ranking = 0.25keywords = chromosome (Clic here for more details about this article) |
9/1493. Renal function studies in an infant with 4p (-) syndrome.An infant with the syndrome of deletion of the short arm of chromosome 4 is described. In addition, this child had renal insufficiency, which is found rarely in association with the 4p(--) syndrome. Previous reports of this syndrome have described only isolated gross structural abnormalites of the urinary tract. In the case discussed here, we present clinical and functional data which indicate that this patient had bilateral renal dysplasia.- - - - - - - - - - ranking = 0.25keywords = chromosome (Clic here for more details about this article) |
10/1493. Infantile autism and associated autosomal chromosome abnormalities: a register-based study and a literature survey.Infantile autism is a heterogenous disorder with unknown aetiology. Evidence from the relatively few family and twin studies suggests a genetic component. Co-occurrence or cosegregation between infantile autism and chromosomal abnormalities may identify candidate regions, which could be tested in linkage or association studies. The purpose of this study was to use the Danish Cytogenetic Central Register in order to detect autosomal chromosome abnormalities associated with infantile autism, and to review the literature for cases of autism associated with autosomal chromosome abnormalities to identify candidate chromosomal regions. The register-based study identified possible candidate regions on chromosome 7q21 and 10q21.2, which have not previously been reported. A few interesting candidate regions, 15q11-13, 16q23, and 17p11.2 were found in the literature survey.- - - - - - - - - - ranking = 1.75keywords = chromosome (Clic here for more details about this article) |
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