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991.
The prognosis of patients receiving allogeneic hematopoietic stem cell transplantation (HSCT) for refractory acute lymphoblastic leukemia (ALL) is very poor. To improve survival rates, we attempted to intensify the conditioning regimen with daunorubicin, vincristine, prednisolone, medium-dose etoposide, cyclophosphamide, and total body irradiation (DNR/VCR/PSL plus medium-dose VP/CY/TBI). Four patients in relapse or induction failure of B-precursor ALL without other complications underwent allogeneic HSCT. Initially, chemotherapy comprising DNR 60 mg/m(2) for 3 days, VCR 1.4 mg/m(2) for 1 day, and PSL 60 mg/m(2) for 3 days was administered, which was followed by medium-dose VP/CY/TBI; some modifications were made for individual patients. All patients achieved engraftment and complete remission after HSCT. Regimen-related toxicities were tolerable and no patient died within 100 days. Two patients were alive without disease on days 563 and 1,055. The third patient relapsed on day 951, while the fourth died on day 179 without disease. Our results indicate that intensified myeloablative HSCT should be considered for patients with refractory ALL.  相似文献   
992.
Background Tissue features to predict the presence or absence of lymph node metastasis (pN) in cases of esophageal squamous cell carcinoma found to contact or penetrate the muscularis mucosae (m3) on endoscopic mucosal resection (EMR) have yet to be clarified in detail. This study was conducted to determine the utility of droplet infiltration (DI) as a candidate. Methods In 27 m3 esophageal squamous cell carcinoma cases who underwent esophagectomy, DI parameters (longitudinal diameter, DIs; number of constituent cells, DIn; distance from the primary focus, DId) for droplet infiltration were examined to allow comparison with vessel permeation (VP) as a predictive factor for lymph node metastasis. Results DIs ≤ 20 μm, DIn ≤ 4, and DId ≥ 200 μm all demonstrated relations with pN (P = 0.001, 0.006, and 0.03, respectively). As predictive factors for lymph node metastasis, DIs ≤ 20 μm and DIn ≤ 4 had sensitivity and likelihood ratios (LR) equal to or higher than VP. Conclusions Tissue features of DI (DIs ≤ 20 μm and DIn ≤ 4) can be applied as predictive factors for lymph node metastasis in m3 esophageal cancers after EMR. This is the English version of a research paper reported in Gastroenterol Endosc 2004;46:2086–94.  相似文献   
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AIM: Lafutidine, a histamine H2 receptor antagonist, exhibits gastro-protective action mediated by capsaicin-sensitive afferent neurons (CSN). We compared the effect between lafutidine and capsaicin, with respect to the interaction with endogenous prostaglandins (PG), nitric oxide (NO) and the afferent neurons, including transient receptor potential vanilloid subtype 1 (TRPV1). METHODS: Male SD rats and C57BL/6 mice, both wild-type and prostacyclin IP receptor knockout animals, were used after 18 h of fasting. Gastric lesions were induced by the po administration of HCI/ethanol (60% in 150 mmol/L HCI) in a volume of 1 mL for rats or 0.3 mL for mice. RESULTS: Both lafutidine and capsaicin (1-10 mg/kg, po) afforded dose-dependent protection against HCI/ ethanol in rats and mice. The effects were attenuated by both the ablation of CSN and pretreatment with NG-nitro-L-arginine methyl ester, yet only the effect of capsaicin was mitigated by prior administration of capsazepine, the TRPV1 antagonist, as well as indomethacin. Lafutidine protected the stomach against HCI/ethanol in IP receptor knockout mice, similar to wild-type animals, while capsaicin failed to afford protection in the animals lacking IP receptors. Neither of these agents affected the mucosal PGE2 or 6-keto PGF1αcontents in rat stomachs. Capsaicin evoked an increase in [Ca2 ]i in rat TRPV1-transfected HEK293 cells while lafutidine did not. CONCLUSION: These results suggest that although both lafutidine and capsaicin exhibit gastro-protective action mediated by CSN, the mode of their effects differs regarding the dependency on endogenous PGs/IP receptors and TRPV1. It is assumed that lafutidine interacts with CSN at yet unidentified sites other than TRPV1.  相似文献   
994.
Increasing recipient age is a well-known risk factor for graft-versus-host disease (GVHD) and treatment-related mortality (TRM) and has a negative impact on allogeneic hematopoietic stem cell transplantation. Since the incidence of severe GVHD after cord blood transplantation (CBT) is lower than that after transplants using bone marrow or mobilized peripheral blood grafts from adult cells, we should expect better outcomes from CBT in older patients. To evaluate the feasibility and efficacy of myeloablative unrelated CBT in patients aged between 50 and 55 years, we performed a retrospective comparison of 100 patients with acute leukemia who received cord blood grafts at our institution. Nineteen older patients (median age, 52; range, 50–55) and 81 younger patients (median, 36; range, 16–49) received a myeloablative conditioning regimen including 12 Gy of total body irradiation and chemotherapy. GVHD prophylaxis included cyclosporine with (n = 96) or without (n = 4) methotrexate. There were no significant differences in the incidences of grades II to IV acute GVHD, extensive-type chronic GVHD, TRM, and the probability of overall and disease-free survival between these groups. These results suggest that, in patients with acute leukemia, myeloablative CBT might be as safe and effective in patients aged between 50 and 55 years as in younger patients.  相似文献   
995.
Background and Aim:  Multipotential mesenchymal stem cells (MSC), present in many organs and tissues, represent an attractive tool for the establishment of a successful stem cell-based therapy in the field of regeneration medicine. Adipose tissue mesenchymal stem cells (AT-MSC), known as adipose-derived stem cells (ASC) are especially attractive in the context of future clinical applications because of their high accessibility and minimal invasiveness during the procedure to obtain them. The goal of the present study was to induce human ASC into functional hepatocytes in vitro within a very short period of time and to check their therapeutic potential in vivo .
Methods:  In vitro generated ASC-derived hepatocytes were checked for hepatocyte-specific markers and functions. Afterwards, they were transplanted into nude mice with liver injury. Twenty-four hours after transplantation, biochemical parameters were evaluated in blood serum.
Results:  We have shown here that ASC can be differentiated into hepatocytes within 13 days and can reach the functional properties of primary human hepatocytes. After transplantation into mice with acute liver failure, ASC-derived hepatocytes can restore such liver functions as ammonia and purine metabolism. Markers of liver injury, alanine aminotransferase, aspartate aminotransferase, as well as ammonia, were decreased after ASC-derived hepatocyte transplantation.
Conclusions:  Our data highlight the properties of ASC as having a special affinity for hepatocyte differentiation in vitro and liver regeneration in vivo . Thus, ASC may be a superior choice for the establishment of a therapy for injured liver.  相似文献   
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