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101.
We studied two cases with leukemia that relapsed in the central nervous system (CNS) after allogeneic stem cell transplantation. One patient underwent peripheral blood stem cell transplantation (SCT) from a related, yet haplotype-mismatched, donor for chronic myelomonocytic leukemia. She was kept in complete remission (CR) in the bone marrow (BM) for 7 months, until relapse in the cerebrospinal fluid (CSF) was evident. In the other patient, with acute lymphoblastic leukemia, systemic relapse occurred when he was still on immunosuppression 6 months after SCT from an unrelated donor. After induction chemotherapy following cessation of immunosuppression, the BM examination proved CR. During consolidation chemotherapy, however, he developed leukemic dissemination in the CSF, despite the fact that the BM was in CR. Chimerism status in the BM mononuclear cells and fractionated peripheral blood (PB) cells (granulocytes, T-lymphocytes, and the others) was assessed by short tandem repeat analysis. In both patients, the BM cells and all the fractions of the PB cells proved donor-type chimeras. These results seem to suggest that the graft-versus-leukemia effects might not be as effective in the CNS as in the BM, even when complete T-lymphoid chimerism is achieved.  相似文献   
102.
The Eisai hyperbilirubinemic rat is a mutant strain of Sprague-Dawley origin with hereditary defects in the biliary excretion of bilirubin glucuronide, glutathione, and several other organic anions. The correlation between bile flow and bile acid excretion rates during taurocholate infusion revealed that bile acid-independent flow was smaller in the mutant than in intact Sprague-Dawley rats (19.3 vs 56.0 μl/kg per min), while bile acid-dependent flow was similar. The correlation between bile flow and glutathione excretion rates in Sprague-Dawley rats with modified hepatic glutathione levels revealed that a certain portion of bile flow was proportional to the biliary excretion of glutathione, with a coefficient of 551 bile per 1 mol glutathione. One-third of bile acid-independent bile flow in intact Sprague-Dawley rats was accounted for by glutathione osmosis, which feature was absent in the mutant rats.  相似文献   
103.
Background and Aims: A prospective , non‐randomized cohort study on long‐term lamivudine treatment , comparing efficacy, drug resistance, and prognosis for various stages of chronic hepatitis B virus (HBV)–related liver disease was performed to elucidate the significance and indication of lamivudine for individual patients at each stage of disease. Methods: A total of 158 cases consisting of 87 chronic hepatitis, 28 compensated cirrhosis, and 43 decompensated cirrhosis, with serum HBV‐DNA > 5 log10 copies/mL and with elevated alanine aminotransferase (ALT) over twice the upper normal limit or complications of hepatic insufficiency, were administered 100 mg of lamivudine daily and monitored for HBV markers, biochemistry, and prognosis. Results: Lamivudine reduced HBV‐DNA and ALT equally in all groups. Serum albumin, prothrombin time (%), and platelet count increased in all groups. The increased margin of albumin was the highest in the decompensated cirrhosis and higher in the compensated cirrhosis than the chronic hepatitis groups. Cumulative incidence of virologic breakthrough was 16%, 42%, 49%, and 53% at 12, 24, 36, and 48 months, respectively, and the strongest predictive factor for lamivudine resistance was persistent HBV‐DNA at 3 months. Ascites, encephalopathy, and jaundice improved in the majority of patients with decompensated cirrhosis. On the other hand, hepatic failure developed or deteriorated in 10 patients after virologic breakthrough, and nine of them had decompensated cirrhosis. Conclusions: Lamivudine was effective in reducing HBV‐DNA and improving hepatic reserve at all stages and was most beneficial and significant for decompensated cirrhosis. Meanwhile, close monitoring of viral load and immediate rescue treatment for lamivudine resistance is necessary to prevent hepatic failure in decompensated cirrhosis.  相似文献   
104.
Synthetic muramyldipeptide (MDP), the minimum structural moiety of bacterial peptidoglycan for adjuvant and related activities, sensitized mice for two types of lethal shock induced by lipopolysaccharide (LPS): an early anaphylactoid shock and late endotoxin shock. In relation to the late reaction in MDP-primed mice, enhanced production of inflammatory cytokines was induced in response to various bacterial components. MDP showed a priming effect in mice not only when administered parentally but also via the oral route. MDP activated human monocytic THP-1 cells in a CD14-, Toll-like receptor 2 (TLR2)- and TLR4-independent manner to increase expression of MyD88, a common adaptor and signaling molecule for TLRs, and exhibited synergistic cytokine inducing effects with TLR4 agonists (LPS, synthetic lipid A), TLR2 agonist (synthetic lipopeptide), and TLR9 agonist (bacterial CpGDNA) in THP-1 cells in culture. Consistent with these findings, MDP primed TLR2 knockout mice as well as wild-type controls, but not TLR4-mutated C3H/HeJ mice, to enhance production of tumor necrosis factor-alpha upon stimulation with synthetic lipid A. In contrast to the BCG- and Propionibacterium acnes-priming system, MDP primed mice in an interferon-gamma-independent manner. Further studies are required to elucidate the mechanisms of the synthetic and priming activities of MDP for various bacterial components.  相似文献   
105.
We present the case of a 55-year-old man who underwent transsacral local excision for a rectal submucosal tumor-like lesion suspected to originate from tuberculosis. The lesion, 2 cm in size, was found incidentally in the posterior wall of the lower rectum during anal fistulectomy. The lesion was apart from the primary crypt of the anal fistula. Barium enema and colonoscopy revealed a protuberant submucosal growth with a shallow depression of the overlying mucosa. Although computed tomography and magnetic resonance imaging showed a well defined round mass within the rectal wall, digital rectal examination suggested extramural origin. Since repeated endoscopic biopsies were negative, we selected the transsacral approach for excisional biopsy to achieve histological diagnosis. The lesion was confined to the rectal wall and the full-thickness rectal wall was excised. Histologically, a foreign-body granuloma with acute inflammation was the main component of the lesion. Caseating granulomas and Langhans' giant cells, consistent with tuberculosis, were also found.  相似文献   
106.
PURPOSE: The aim of this study was to clarify the distribution of lymph node metastasis in colorectal cancer. We also examined the relationship between the primary tumor (T) and the regional node (N) categories of the TNM (primary tumor, regional nodes, metastasis) classification. METHOD: Lymph nodes of surgical specimens in 311 consecutive patients with colorectal cancer were studied using the modified clearing method. RESULTS: Lymph node metastasis was seen in 59.2 percent of the total cases. The upward metastasis rate was 30.7 percent. In the longitudinal spread, most of the lymph node metastasis was seen within 10 cm. On the oral side in rectal cancer, there was no metastasis beyond 4 cm. The lateral metastasis rate in rectal cancer was 8.8 percent and in the lower rectum, the rate of cancer within 6 cm from the anal verge or beyond pT3 was much higher. CONCLUSION: In the TNM classification, there was no significant difference between colon and rectal cancer except pT1 with rectal cancer. In the lower rectal cancer within 6 cm from the anal verge or beyond pT3, there is a high risk of lateral metastasis, and lateral lymph node dissection or radiation therapy should be performed.  相似文献   
107.
The aim of the present study was to explore the unfavorable subset of patients with Stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0). Recurrence-free survival rates were examined in 52 patients with stage T1N2-3M0 and stage T3N0M0 gastric cancer between January 2000 and March 2010. Univariate and multivariate analyses were performed to identify risk factors using a Cox proportional hazards model. The recurrence-free survival (RFS) rates of the patients with stages T1N2, T1N3, and T3N0 cancer were 80.0, 76.4, and 100% at 5 years, respectively. The only significant prognostic factor for the survival rates of the patients with stage pT1N2-3 cancer measured by univariate and multivariate analyses was pathological tumor diameter. The 5-year RFS rates of the patients with stage pT1N2-3 cancer were 60.0%, when the tumor diameters measured <30 mm, and 88.9% when the tumor diameters measured >30 mm (P = 0.0248). These data may suggest that pathological tumor diameter is associated with poor survival in patients with small T1N2-3 tumors. Because our study was a retrospective single-center study with a small sample size, a prospective multicenter study is necessary to confirm whether small tumors are risk factor for the RFS in T1N2-3 disease.Key words: Gastric cancer, Stage II, Adjuvant chemotherapyEvery year, more than 934,000 people develop gastric cancer worldwide. After lung cancer, gastric cancer is the second most frequent cancer-related cause of death.1 Complete resection is essential to cure gastric cancer. Patients with stage II or stage III gastric cancer often develop tumor recurrence, even after complete curative resections.In 2007, the Adjuvant Chemotherapy Trial of S-1 for Gastric Cancer (ACTS-GC) phase III trial demonstrated that S-1 is effective as adjuvant chemotherapy in Japanese patients who have undergone curative D2 gastrectomy for advanced gastric cancer.2 In general, patients eligible for ACTS-GC were those diagnosed with pathological stages II and III. However, patients classified with pathological (p) stages T1N2M0, T1N3M0, and T3N0M0—which are classified as part of stage II—were excluded from the ACTS-GC trial. Because in the prior phase III studies comparing surgery alone and adjuvant chemotherapy, patients with stages T1N+ and T2-3/N0 cancer had excellent prognoses with 5-year overall survival (OS) rates of more than 80% from surgery alone,3,4 these patients were excluded from receiving adjuvant chemotherapy. Japanese Gastric Cancer Association (JGCA) guidelines clearly state that the standard treatment for these patients is surgery alone.5Therefore, patients with stage II gastric cancer have been divided into two groups: one for whom the standard treatment is surgery alone, and the other for whom the standard treatment is surgery and adjuvant chemotherapy with S-1. Before the advent of ACTS-GC, survival rates were poorer in the latter group than in the former. However, treatment with adjuvant chemotherapy with S-1 has reversed this trend. Now, patients in the latter group receiving S-1 adjuvant chemotherapy have 5-year OS rates of 84.2%.6 Therefore, it may be old rationale that dictates that patients in the former group should be excluded from receiving adjuvant chemotherapy, because the 5-year OS rates are now more than 80% by S-1 adjuvant chemotherapy in the latter group. Five-year OS rates of 80% would not be obtained by surgery alone. Among those patients with stage II gastric cancer assigned to the surgery alone group, some may have a poor prognosis and be good candidates for adjuvant chemotherapy. The aim of the present study was to explore the unfavorable subset of patients among those with stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0).  相似文献   
108.
Chromosomal translocations that involve the monocytic leukemia zinc finger (MOZ) gene are typically associated with human acute myeloid leukemia (AML) and often predict a poor prognosis. Overexpression of HOXA9, HOXA10, and MEIS1 was observed in AML patients with MOZ fusions. To assess the functional role of HOX upregulation in leukemogenesis by MOZ–TIF2, we focused on bromodomain-PHD finger protein 1 (BRPF1), a component of the MOZ complex that carries out histone acetylation for generating and maintaining proper epigenetic programs in hematopoietic cells. Immunoprecipitation analysis showed that MOZ–TIF2 forms a stable complex with BRPF1, and chromatin immunoprecipitation analysis showed that MOZ–TIF2 and BRPF1 interact with HOX genes in MOZ–TIF2-induced AML cells. Depletion of BRPF1 decreased the MOZ localization on HOX genes, resulting in loss of transformation ability induced by MOZ–TIF2. Furthermore, mutant MOZ–TIF2 engineered to lack histone acetyltransferase activity was incapable of deregulating HOX genes as well as initiating leukemia. These data indicate that MOZ–TIF2/BRPF1 complex upregulates HOX genes mediated by MOZ-dependent histone acetylation, leading to the development of leukemia. We suggest that activation of BRPF1/HOX pathway through MOZ HAT activity is critical for MOZ–TIF2 to induce AML.  相似文献   
109.
Essential thrombocythemia (ET) is a subtype of myeloproliferative neoplasms. Approximately half of the patients with ET harbor a gain-of-function mutation in the JAK2 gene (JAK2-V617F), a small percentage have mutations in codon 515 of MPL (thrombopoietin receptor) gene, and the rest have neither mutation. Pregnancy is a rare complication of ET, and it has been reported that the number of blood platelets falls with pregnancy in ET patients and the number of blood platelets increases again after a delivery and this phenomenon is observed in JAK2-V617F-positive and JAK2-V617F-negative patients. We report the first case of an ET patient with MPL mutations, whose platelet count improved with the onset of menopause, not pregnancy, and the MPL mutation also simultaneously disappeared.  相似文献   
110.
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