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1.
p = 0.0007) and tumor necrosis (TN) (HMC: p = 0.0050). Univariate analysis showed that AMC or HMC was a statistically significant predictor of overall survival in all patients ( p = 0.0086 and p = 0.0307, respectively). Multivariate analysis showed that AMC was an independent predictor of node status when we fitted a model with node status, BVI, and either AMC or HMC; but HMC was not independent. However, when we fitted a model including all 11 of the other indicators and AMC or HMC, the node status, HG, and LI were independent predictors, but AMC and HMC were not. Although AMC was a better method than HMC for evaluating angiogenesis, we cannot confirm angiogenesis as a significant independent prognostic factor associated with long-term survival in Japanese breast cancer patients.  相似文献   
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A 46-year-old man with chronic myelogenous leukemia was found to have a new complex translocation. In chronic phase, all of the bone marrow cells had a rearrangement of a t(2;9;14;22) (p21;q34;q32;q11). Southern blot analysis of leukocyte DNA revealed rearrangement of the breakpoint cluster region (bcr) within the 5.8-Kb bcr. The patient eventually died in blast crisis 28 months later. The cytogenetic findings of bone marrow cells showed a 46,XY,t(2;9;14;22)(p21;q34;q32;qll),add(lp),del(3q) karyotype in blast crisis.  相似文献   
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Tetrasomy 8, though rare, is usually associated with trisomy 8, a far more common chromosomal abnormality in acute myeloid leukemia (AML). Yet the clonal relationship between trisomy 8 and tetrasomy 8 in the cases with these chromosomal abnormalities has been unclear. Here, we report a case of a 17-year-old male, diagnosed as having a myelodysplastic syndrome (MDS). Chromosome analysis showed the presence of trisomy 8. Five years later, he developed overt AML exhibiting tetrasomy 8 only. After chemotherapy, the blast cells in the bone marrow decreased to 3.4%, and the karyotype showed trisomy 8 alone. Fluorescence in situ hybridization using a probe specific for chromosome 8 showed that the percentages of cells exhibiting 2/ 3 /4 signals were 7.8/89.2/2.0 at the MDS stage, 20.5/36.1/41.0 when overt AML developed and 24.0/72.1/2.4 after chemotherapy. These results suggested that tetrasomy 8 is derived from the AML clone, possibly evolved from the MDS clone with trisomy 8. To our knowledge, this is the first detailed case report of clonal evolution from trisomy 8 into tetrasomy 8 associated with the development of AML from MDS.  相似文献   
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PURPOSE: Increases in gene dosage through DNA amplification represents a common feature of many tumors and can result in the up-regulation of tumor-promoting genes. Our recent genome-wide, array-based comparative genomic hybridization analysis of 66 cases of diffuse large B-cell lymphoma found that genomic gain of 6p21 was observed in as many as 17 cases, including 14 cases with low-level copy number gain and three cases with high-level copy number gains (amplifications). EXPERIMENTAL DESIGN AND RESULTS: To identify the target gene(s) for 6p21 amplification, we constructed a detailed amplicon map at the region of genomic amplification with the aid of high-resolution contig array-based comparative genomic hybridization glass slides, consisting of contiguously ordered bacterial artificial chromosome/P1-derived artificial chromosome clones covering 3 Mb throughout the 6p21 amplification region. Alignment of the amplifications identified a minimally overlapping 800 kb segment containing 15 genes. Quantitative expression analysis of the genes from both patient samples and the SUDHL9 cell line revealed that CCND3 and BYSL (1.9 kb telomeric to the CCND3 gene locus) are the targets of 6p21 genomic gain/amplification. CONCLUSIONS: Although it is known that t(6;14)(p21;q32) induces aberrant overexpression of CCND3 in B-cell malignancies, we were able to show that CCND3, which encodes the cyclin D family member protein that controls the G1-S phase of cell cycle regulation, can also be a target of genomic gain/amplification. Overexpression of CCND3 through genomic amplification is likely to lead to aberrant cell cycle control, although the precise biological role of BYSL with respect to tumorigenesis remains to be determined.  相似文献   
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OBJECTIVE: To examine the expression and regulation of chemotactic factor, macrophage inflammatory protein-1alpha (MIP-1alpha) by fibroblast-like synoviocytes (FLS), monocytes and polymorphonuclear neutrophils (PMN) isolated from the synovial fluid (SF) of rheumatoid arthritis (RA) patients. METHODS: Monocytes or PMN obtained from RA SF were co-cultured with unstimulated semiconfluent RA FLS. Culture supernatants were assayed for MIP-1alpha by enzyme-linked immunosorbent assay. The expression of MIP-1alpha mRNA and protein was also determined by Northern blot analyss and immunohistochemistry respectively. RESULTS: Interaction of activated leucocytes with FLS synergistically increased MIP-1alpha expression and secretion via a mechanism mediated by beta2-integrin/ intercellular adhesion molecule 1. CONCLUSION: MIP-1alpha expression within inflamed joints appears to be regulated not only by inflammatory cytokines but also by the physical interaction of activated leucocytes and FLS, and plays a crucial role in the progression and maintenance of RA synovitis.  相似文献   
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BACKGROUND/AIMS: Activation of reticuloendothelial system functions by the treatment with OK-432 has been reported to enhance liver regeneration. However, its effect on liver regeneration has not been studied after hepatectomy under ischemia/reperfusion which is in clinical use. The aim was to examine the effect of OK-432 on regeneration and energy status of the liver after hepatectomy under ischemia/reperfusion in rats. METHODOLOGY: Rats were randomly divided into two groups; OK-432 pretreatment and saline treatment (control) group. In the OK-432 group, OK-432 (2.5 mg/kg body weight) was administered intraperitoneally 24 hours before hepatectomy. In the control group, the same volume of physiological saline was administered in the same manner. Seventy percent hepatectomy was performed in both groups during the second 15-minute ischemia period after an initial 15-minute ischemia and 15-minute reperfusion periods. The survival after hepatectomy, relative liver weight, deoxyribonucleic acid synthesis rate, and hepatic adenine nucleotide and energy charge levels were examined immediately after hepatectomy and on postoperative days 1, 2, 3, and 7. Serum levels of total bilirubin, glutamic pyruvic transaminase, and hyaluronic acid were also measured. RESULTS: All rats survived and the relative liver weight and deoxyribonucleic acid synthesis rate were not significantly different in the two groups. Serum total bilirubin and glutamic pyruvic transaminase levels were not significantly different in both groups. The serum concentration of hyaluronic acid immediately after hepatectomy was significantly higher in the OK-432 group than in the control group. The pretreatment with OK-432 had no significant effect on the levels of adenine nucleotides and energy charge in the liver. CONCLUSIONS: Under ischemia/reperfusion, pretreatment with OK-432 has no significant effect on regeneration and energy status of the liver after hepatectomy.  相似文献   
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Patients who have undergone allogeneic bone marrow transplantation (allo-BMT) are susceptible to a variety of opportunistic infectious complications in the months to years after engraftment. Impaired in vitro T-cell functions have been documented in these patients, and these T-cell dysfunctions contribute to the prolonged immune deficiency after allo-BMT. In the present study, we examined the expression of CD26 as well as the reconstitution of CD26-mediated T-cell costimulation via the CD3 and CD2 pathways at various times in patients aged greater than 18 years after CD6-positive, T-cell depleted allo- BMT. We found that the percentage of CD26- and CD3-positive cells, as well as the levels of expression of both antigens, was lower than in normal controls during the first 4 months after CD6-depleted allo-BMT. Subsequently, the amount of lymphocytes expressing CD3 and CD26 and the quantitative surface expression of CD3 and CD26 were not significantly different in patients and normal controls. Functional studies showed that CD26-mediated T-cell proliferation via the CD3 pathway was considerably improved and almost reached normal levels by 1 year, whereas recovery of CD26-mediated T-cell proliferation via the CD2 pathway was delayed for at least 2 years after CD6-depleted allo-BMT. As CD26 involvement in the regulation of human thymocyte activation is restricted preferentially to the CD3 pathway--unlike its involvement with both CD3 and CD2 pathways of peripheral T cells--our results suggest that the different effects of CD26-mediated costimulation via the CD3 and CD2 pathways after CD6-depleted allo-BMT may be a reflection of peripheral T-cell immaturity in those individuals, similar to that seen in mature medullary thymocytes or cord T lymphocytes.  相似文献   
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