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Superior mesenteric venous thrombosis (SMVT) is an uncommon but potentially life-threatening disorder. We describe a cirrhotic patient with hepatocellular carcinoma who had partial SMVT for at least 28 months. Our experience may help in the management of such patients. The partial SMVT was not treated at the time of discovery because there was no evidence of bowel infarction. Moreover, the patient had a tendency to bleed severely and was in a poor condition. SMVT was followed using regular ultrasonography and the pattern of SMVT did not change significantly during the follow-up period. A symptom that may have been related to SMVT was abdominal colic pain after meals, which was sometimes followed by diarrhea and / or nausea and vomiting. There was no evidence of bowel ischemia or infarction during follow-up. Abdominal discomfort can be successfully treated using anticholinergic drugs with or without analgesia. 相似文献
173.
Clonal evolution and lack of cytogenetic response are adverse prognostic factors for hematologic relapse of chronic phase CML patients treated with imatinib mesylate 总被引:2,自引:3,他引:2 下载免费PDF全文
O'Dwyer ME Mauro MJ Blasdel C Farnsworth M Kurilik G Hsieh YC Mori M Druker BJ 《Blood》2004,103(2):451-455
We followed 141 patients treated with imatinib mesylate (> 300 mg) for chronicphase chronic myelogenous leukemia (CML) following failure of treatment with interferon. During 12 months from the start of imatinib mesylate treatment, 96.5% achieved a complete hematologic response, 47.0% achieved a major cytogenetic response, and 32.4% achieved a complete cytogenetic response. The proportion of patients with hematologic relapse was 10.9% at 12 months and 14.6% at 18 months. In a univariate Cox regression analysis, the only pretreatment characteristics that correlated with an increased risk of hematologic relapse were hemoglobin level less than 120 g/L (12 g/dL) (P =.02), increased bands in the peripheral blood (P =.01), and clonal evolution (P <.0001). In a multivariate analysis, an elevated platelet count (P =.03) and clonal evolution (P <.0001) were the only significant factors for hematologic relapse. During treatment, the absence of a major cytogenetic response within the first 6 months also significantly correlated with relapse (P =.03). Notably, patients failing to achieve a major cytogenetic response by 6 months had a significantly higher rate of hematologic relapse (27%) compared with those who achieved a major cytogenetic response by 6 months (3%), and patients with clonal evolution had a significantly higher risk of hematologic relapse (50%) than those without clonal evolution (9%). 相似文献
174.
OBJECTIVE: In utero hematopoietic cell transplantation (IUHCT) typically achieves low-level mixed hematopoietic chimerism. However, the goal of IUHCT is to achieve therapeutic levels of chimerism. We hypothesized that prenatal adoptive immunotherapy might achieve high-level donor chimerism after IUHCT. MATERIALS AND METHODS: BALB/CE15 fetal mice were transplanted with a mixture of C57BL/6 (B6) T-cell-depleted bone marrow (TCD BM) cells and splenocytes from B6 mice presensitized to BALB/C alloantigen. The splenocytes were preincubated in L-leucyl-L-leucine methyl ester (LLME), to minimize graft vs host disease (GVHD). Recipients were followed after birth for donor cell chimerism and GVHD. RESULTS: Full donor hematopoietic chimerism following a single prenatal transplant was achieved in seven transplanted animals. Fully chimeric animals were healthy, without evidence of GVHD, and maintained their engraftment for the duration of the study (48 weeks). However, the addition of presensitized LLME-treated cells decreased survival until weaning relative to TCD BM alone, suggesting that some animals were lost to acute GVHD. Surviving chimeric animals demonstrated increased frequencies of T-regulatory cell populations in their spleen and BM, suggesting that they had successfully suppressed GVHD, allowing survival. CONCLUSIONS: This study represents "proof in principle" that prenatal immunotherapeutic strategies may achieve complete hematopoietic engraftment across full MHC barriers when combined with IUHCT. However, strategies with greater hematopoietic specificity must be developed prior to consideration of clinical application. 相似文献
175.
Phosphatidylinositol 3-kinase is required for insulin-like growth factor-I-induced vascular smooth muscle cell proliferation and migration 总被引:12,自引:0,他引:12
Insulin-like growth factor-I (IGF-I) plays an important role in regulating vascular smooth muscle cell (VSMC) proliferation and directed migration. The mitogenic and chemotactic actions of IGF-I are mediated through the IGF-I receptor, but how the activation of the IGF-I receptor leads to these biological responses is poorly understood. In this study, we examined the role of phosphatidylinositol 3-kinase (PI3 kinase) in mediating the mitogenic and chemotactic signals of IGF-I. IGF-I treatment resulted in a significant increase in phosphotyrosine-associated PI3 kinase activity in cultured primary VSMCs. To determine whether insulin receptor substrate (IRS)-1, -2, or both are involved in IGF-I signaling in VSMCs, cell lysates were immunoprecipitated with either an anti-IRS-1 or an anti-IRS-2 antibody, and the associated PI3 kinase activity was determined. IGF-I stimulation resulted in a significant increase in IRS-1- but not IRS-2-associated PI3 kinase activity, suggesting that IGF-I primarily utilizes IRS-1 to transmit its signal in VSMCs. The IGF-I-induced increase in IRS-I-associated PI3 kinase activity was concentration dependent. At the maximum concentration (50 ng/mL), IGF-I induced a 60-fold increase. This activation occurred within 5 minutes and was sustained at high levels for at least 6 hours. IGF-I also caused a concentration-dependent and long-lasting activation of protein kinase B (PKB/Akt). Inhibition of PI3 kinase activation by LY294002 or wortmannin abolished IGF-I-stimulated VSMC proliferation and reduced IGF-I-directed VSMC migration by approximately 60%. These results indicate that activation of PI3 kinase is required for both IGF-I-induced VSMC proliferation and migration. 相似文献
176.
Probing the Saccharomyces cerevisiae centromeric DNA (CEN DNA)-binding factor 3 (CBF3) kinetochore complex by using atomic force microscopy 总被引:1,自引:0,他引:1 下载免费PDF全文
Pietrasanta LI Thrower D Hsieh W Rao S Stemmann O Lechner J Carbon J Hansma H 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(7):3757-3762
Yeast centromeric DNA (CEN DNA) binding factor 3 (CBF3) is a multisubunit protein complex that binds to the essential CDEIII element in CEN DNA. The four CBF3 proteins are required for accurate chromosome segregation and are considered to be core components of the yeast kinetochore. We have examined the structure of the CBF3-CEN DNA complex by atomic force microscopy. Assembly of CBF3-CEN DNA complexes was performed by combining purified CBF3 proteins with a DNA fragment that includes the CEN region from yeast chromosome III. Atomic force microscopy images showed DNA molecules with attached globular bodies. The contour length of the DNA containing the complex is approximately 9% shorter than the DNA alone, suggesting some winding of DNA within the complex. The measured location of the single binding site indicates that the complex is located asymmetrically to the right of CDEIII extending away from CDEI and CDEII, which is consistent with previous data. The CEN DNA is bent approximately 55 degrees at the site of complex formation. A significant fraction of the complexes are linked in pairs, showing three to four DNA arms, with molecular volumes approximately three times the mean volumes of two-armed complexes. These multi-armed complexes indicate that CBF3 can bind two DNA molecules together in vitro and, thus, may be involved in holding together chromatid pairs during mitosis. 相似文献
177.
Rong‐Kuo Lyu Wei‐Hung Chen Sung‐Tsang Hsieh 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2002,6(2):163-166
Abstract: Previous studies have shown that both plasma exchange (PE) and double filtration plasmapheresis (DFPP) are effective treatments in Guillain‐Barré syndrome (GBS). Whether PE and DFPP have similar effects in GBS is not clear. This report compares the therapeutic effectiveness of PE and DFPP in GBS patients treated in 3 major hospitals in northern Taiwan. A total of 102 patients were included in this survey, including 39 with PE (hereafter PE group) and 63 with DFPP (hereafter DFPP group). Both groups showed significant improvement of disability scores after treatment. However, time to onset of effect was shorter (5.6 ± 3.5 versus 7 ± 3.4 days, p < 0.05), and changes of disability scores were more prominent (1.3 ± 0.8 versus 0.8 ± 0.8, p < 0.05) in the PE group than the DFPP group. Mortality and outcome after 6 months were not different between the 2 groups. In conclusion, both PE and DFPP are effective treatments in GBS. PE was superior to DFPP in short‐term effectiveness. The long‐term effectiveness was not different. 相似文献
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