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排序方式: 共有382条查询结果,搜索用时 15 毫秒
1.
A cytogenetic study of 53 human gliomas   总被引:8,自引:1,他引:8  
Cytogenetic studies were performed on human glioma samples obtained by stereotactic biopsy, stereotactic craniotomy, or routine craniotomy. Using in situ culture and robotic harvesting techniques, we obtained suitable metaphases in 50 (94%) of 53 tumors, including 28 diffuse astrocytomas, four juvenile pilocytic astrocytomas, two gliosarcomas, three other miscellaneous astrocytomas, eight oligodendrogliomas, four mixed oligodendroglioma-astrocytomas, and four ependymomas. Cytogenetic studies were performed only on primary cultures; the mean culture time was 9.6 days (range 1-31 days). One or more chromosomally abnormal clones were observed in 35 (66%) tumors. Eleven (21%) other specimens had random nonclonal chromosome abnormalities. In four (8%) specimens, no chromosome abnormalities were noted. The results of this study suggest that grade 3 and 4 tumors are more likely to contain an abnormal clone than tumors of grade 1 or 2 (p less than 0.01). The most common numeric chromosome abnormalities were -6, +7, -10, -13, -14, -15, -18, and -Y. The most common structural abnormalities involved 1p, 6q, 7q, 8p, 9p, 11p, 11q, 13q, and 19q. Four tumors had two or more independent clones and ten contained subclones demonstrating karyotype evolution. With in situ culture and robotic harvesting techniques, cytogenetic studies can be successful on nearly all human gliomas, including those derived from small stereotactic biopsies.  相似文献   
2.
A mentally retarded female child with multiple congenital abnormalities had an abnormal X chromosome and a Y chromosome; the karyotype was interpreted as 46,dup(X)(p21 leads to pter)Y. Prenatal chromosome studies in a later pregnancy indicated the same chromosomal abnormality in the fetus. The fetus and proband had normal female genitalia and ovarian tissue. H--Y antigen was virtually absent in both sibs, a finding consistent with the view that testis-determining genes of the Y chromosome may be suppressed by regulatory elements of the X. The abnormal X chromosome was present in the mother, the maternal grandmother, and a female sib: all were phenotypically normal and showed the karyotype 46,Xdup(X)(p21 leads to pter) with non-random inactivation of the abnormal X. Anomalous segregation of the Xga allele suggests that the Xg locus was involved in the inactivation process or that crossing-over at meiosis occurred.  相似文献   
3.
The nonrandom recurrent nature of chromosome abnormalities in myeloma suggests a role for them in disease pathogenesis. We performed a careful cytogenetic analysis of patients with abnormal karyotypes (n = 254), to discern patterns of association, search for novel abnormalities and elucidate clinical implications. Patients with karyotypic abnormalities suggestive of myelodysplasia/acute leukemia were excluded. In this study we compared survival by abnormality only between patients with abnormal karyotypes. Patients with abnormalities were more likely to have features of aggressive disease as compared to all other patients without abnormalities entered into the myeloma database (lower hemoglobin, higher beta(2)-microglobulin, labeling-index and plasmocytosis; all P < 0.0001). Several groups of patients could be readily identified; hypodiploid (22%), pseudodiploid (36%), hyperdiploid (31%) and near-tetraploid (11%). Clustering associations were seen among several trisomies and monosomy of chromosome 13 and 14. Several monosomies (-2, -3, -13, -14 and -19), 1p translocations/ deletions, and hypodiploidy were associated with a significantly shorter survival. Trisomy of chromosome 13 was rare ( <2%). Even among patients with abnormal karyotypes, specific chromosome abnormalities can impart biologic variability in myeloma, including several monosomies, hypodiploidy and abnormalities of 1p.  相似文献   
4.
A 9-year-old boy with Kawasaki disease survived after two severe myocardial infarctions. Thereafter pharmacologically untreatable ventricular arrhythmia and rapidly deteriorating heart failure developed in the patient. After 19 days of biventricular and a further 27 days of left univentricular mechanical circulatory support with the Berlin Heart (Cardiotechnica, Berlin, Germany) assist device the boy successfully underwent heart transplantation. At a follow-up of 54 months, the boy is leading an active and unrestricted life.  相似文献   
5.
An identical chromosome abnormality, which appears to be derived from a 1;7 translocation [+der(1),t(1;7)(p11;p11)], was observed in the bone marrow of 12 patients with various hematologic disorders at the Mayo Clinic from 1980 to 1984. At the time of cytogenetic evaluation, nine of the patients had either a myeloproliferative disorder or a myelodysplastic syndrome, one had an acute leukemia, and two had treated multiple myeloma with no morphologic evidence of evolving myeloproliferative disease. Of the 11 patients for whom information about previous therapy was available, seven had a history of exposure to chemotherapy for a previous malignant disorder; we were unable to establish whether the remaining patient had had prior treatment. This study suggests a possible relationship between +der(1),t(1;7)(p11;p11) and some treatment-induced hematologic disorders. Such chromosome abnormalities may be the result of a reciprocal chromatid translocation and adjacent I segregation of a quadriradial configuration in metaphase.  相似文献   
6.
Bhatia  R; McGlave  PB; Dewald  GW; Blazar  BR; Verfaillie  CM 《Blood》1995,85(12):3636-3645
The bone marrow microenvironment supports and regulates the proliferation and differentiation of hematopoietic cells. Dysregulated hematopoiesis in chronic myelogenous leukemia (CML) is caused, at least in part, by abnormalities in CML hematopoietic progenitors leading to altered interactions with the marrow microenvironment. The role of the microenvironment itself in CML has not been well characterized. We examined the capacity of CML stroma to support the growth of long-term culture-initiating cells (LTC-IC) obtained from normal and CML marrow. The growth of normal LTC-IC on CML stroma was significantly reduced compared with normal stroma. This did not appear to be related to abnormal production of soluble factors by CML stroma because normal LTC- IC grew equally well in Transwells above CML stroma as in Transwells above normal stroma. In addition, CML and normal stromal supernatants contained similar quantities of both growth-stimulatory (granulocyte colony-stimulating factor (CSF), interleukin-6, stem cell factor, granulocyte-macrophage CSF, and interleukin-1 beta) and growth- inhibitory cytokines (transforming growth factor-beta, macrophage inflammatory protein-1 alpha, and tumor necrosis factor-alpha). The relative proportion of different cell types in CML and normal stroma was similar. However, polymerase chain reaction and fluorescence in situ hybridization studies showed the presence of bcr-abl-positivo cells in CML stroma, which were CD14+ stromal macrophages. To assess the effect of these malignant macrophages on stromal function, CML and normal stromal cells were separated by fluorescence-activated cell sorting into stromal mesenchymal cell (CD14-) and macrophage (CD14+) populations. CML and normal CD14- cells supported the growth of normal LTC-IC equally well. However, the addition of CML macrophages to normal or CML CD14- mesenchymal cells resulted in impaired progenitor support. This finding indicates that the abnormal function of CML bone marrow stroma is related to the presence of malignant macrophages. In contrast to normal LTC-IC, the growth of CML LTC-IC on allogeneic CML stromal layers was not impaired and was significantly better than that of normal LTC-IC cocultured with the same CML stromal layers. These studies demonstrate that, in addition to abnormalities in CML progenitors themselves, abnormalities in the CML marrow microenvironment related to the presence of malignant stromal macrophages may contribute to the selective expansion of leukemic progenitors and suppression of normal hematopoiesis in CML.  相似文献   
7.
A novel oncogenic mutation (FIP1L1-PDGFRA), which results in a constitutively activated platelet-derived growth factor receptor-alpha (PDGFRA), has been invariably associated with a primary eosinophilic disorder. The current study examines both the prevalence and the associated clinicopathologic features of this mutation in a cohort of 89 adult patients presenting with an absolute eosinophil count (AEC) of higher than 1.5 x 10(9)/L. A fluorescence in situ hybridization (FISH)-based strategy was used to detect FIP1L1-PDGFRA in bone marrow cells. None of 8 patients with reactive eosinophilia displayed the abnormality, whereas the incidence of FIP1L1-PDGFRA in the remaining 81 patients with primary eosinophilia was 14% (11 patients). None (0%) of 57 patients with the hypereosinophilic syndrome (HES) but 10 (56%) of 19 patients with systemic mast cell disease associated with eosinophilia (SMCD-eos) carried the specific mutation. The bone marrow mast cell infiltration pattern in FIP1L1-PDGFRA(+) SMCD-eos was distinctly diffuse with loose tumoral aggregates. Treatment with low-dose imatinib (100 mg/d) produced complete and durable responses in all 8 FIP1L1-PDGFRA(+) cases treated. In contrast, only 40% partial response rate was seen in 10 HES cases. FIP1L1-PDGFRA is a relatively infrequent but treatment-relevant mutation in primary eosinophilia that is indicative of an underlying systemic mastocytosis.  相似文献   
8.
We examined the effects of interleukin-12 (IL-12) and interleukin-13 (IL-13) on cytokine, cytokine inhibitor and prostaglandin E (PGE) release from synovial fibroblasts and blood mononuclear cells (MNC). In resting synovial fibroblasts, we found that IL-13 is an inhibitor of IL-8 and PGE release. A significant decrease of PGE synthesis caused by IL-13 was also observed in tumor necrosis factor (TNF)-α-stimulated synovial fibroblasts, whereas IL-12 had no regulatory effects on these cells. In resting and cytokine-stimulated MNC, IL-13 markedly inhibited IL-1β, IL-8 and monocyte chemoattractant protein-1 (MCP-1) release and potently stimulated interleukin-1 receptor antagonist (IL-1ra) synthesis. In contrast, IL-12 stimulated the production of IL-1β and MCP-1 in TNF-α-stimulated MNC and inhibited IL-1ra synthesis in cytokine-stimulated cells. These findings identify novel biological actions of IL-12 and IL-13 on connective tissue and on blood mononuclear cells which indicate their regulatory functions as enhancer and suppressor of inflammatory processes, respectively.  相似文献   
9.
The CC chemokine Monocyte Chemoattractant Protein (MCP)-1/CCL2 has potent mononuclear cell chemo-attractant properties, modulates fibroblast and endothelial cell phenotype and may play an important role in wound healing. In order to examine whether MCP-1 critically regulates myocardial infarct healing, we studied the effects of MCP-1 gene disruption and antibody neutralization in a closed-chest model of reperfused murine myocardial infarction. MCP-1-/- mice had decreased and delayed macrophage infiltration in the healing infarct and demonstrated delayed replacement of injured cardiomyocytes with granulation tissue. In contrast, the time course and density of neutrophil infiltration was similar in MCP-1 null and wild-type animals. MCP-1-/- infarcts had decreased mRNA expression of the cytokines TNF-alpha, IL-1beta, TGF-beta2, -beta3, and IL-10 and demonstrated defective macrophage differentiation evidenced by decreased Osteopontin-1 expression. MCP-1 deficiency diminished myofibroblast accumulation but did not significantly affect infarct angiogenesis. Despite showing delayed phagocytotic removal of dead cardiomyocytes, MCP-1-/- mice had attenuated left ventricular remodeling, but similar infarct size when compared with wild-type animals. MCP-1 antibody inhibition resulted in defects comparable with the pathological findings noted in infarcted MCP-1-/- animals without an effect on macrophage recruitment. MCP-1 has important effects on macrophage recruitment and activation, cytokine synthesis and myofibroblast accumulation in healing infarcts. Absence of MCP-1 results in attenuated post-infarction left ventricular remodeling, at the expense of a prolonged inflammatory phase and delayed replacement of injured cardiomyocytes with granulation tissue.  相似文献   
10.
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