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21.
The small intestine epithelium undergoes rapid and continuous regeneration supported by crypt intestinal stem cells (ISCs). Bmi1 and Lgr5 have been independently identified to mark long-lived multipotent ISCs by lineage tracing in mice; however, the functional distinctions between these two populations remain undefined. Here, we demonstrate that Bmi1 and Lgr5 mark two functionally distinct ISCs in vivo. Lgr5 marks mitotically active ISCs that exhibit exquisite sensitivity to canonical Wnt modulation, contribute robustly to homeostatic regeneration, and are quantitatively ablated by irradiation. In contrast, Bmi1 marks quiescent ISCs that are insensitive to Wnt perturbations, contribute weakly to homeostatic regeneration, and are resistant to high-dose radiation injury. After irradiation, however, the normally quiescent Bmi1(+) ISCs dramatically proliferate to clonally repopulate multiple contiguous crypts and villi. Clonogenic culture of isolated single Bmi1(+) ISCs yields long-lived self-renewing spheroids of intestinal epithelium that produce Lgr5-expressing cells, thereby establishing a lineage relationship between these two populations in vitro. Taken together, these data provide direct evidence that Bmi1 marks quiescent, injury-inducible reserve ISCs that exhibit striking functional distinctions from Lgr5(+) ISCs and support a model whereby distinct ISC populations facilitate homeostatic vs. injury-induced regeneration.  相似文献   
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Using a registration sheet of a prospective registration system for aplastic anemia (AA)/myelodysplastic syndromes (MDS), by the National Research Group on Idiopathic Bone Marrow Failure Syndromes, Japan, we carried out a survey on examinations for diagnosis of bone marrow failure. Bone marrow trephine biopsy was performed in 66 of 105 cases (63%) [Original diagnosis: AA 51 cases (80%), MDS 12 (32%), undiagnosable 3 (75%)]. Bone marrow aspiration was performed in all cases, and aspiration was performed at least twice in 36 cases (34%). The first-line anatomic site for bone marrow aspiration was the posterior iliac crest (62%). Cytogenetic examination was performed in 93%. The concordance rate between the original and the central review diagnosis was 93% among the studied cases: AA, Idiopathic cytopenia of undetermined significance (ICUS) and MDS in total. Flow cytometry analysis to detect paroxysmal nocturnal hemoglobinuria (PNH)-type blood cells was performed in 32%.  相似文献   
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Neurological Sciences - Although bleb formation increases the risk of rupture of intracranial aneurysms, previous computational fluid dynamic (CFD) studies have been unable to identify robust...  相似文献   
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We herein report a case of IgG4-related autoimmune pancreatitis (AIP). A 72-year-old male with jaundice visited our hospital complaining of epigastralgia. A blood chemistry analysis revealed elevated serum levels of total bilirubin and DUPAN-II. Computed tomography (CT) revealed irregularly shaped pancreatic masses with a stricture of the main pancreatic duct (MPD) in the head and tail that were interposed by marked atrophy with MPD dilation in the body. F-18 fluorodeoxyglucose (FDG)-positron emission tomography/CT revealed abnormally intense FDG uptake only at the masses. During surgery, another small tumor was also found in the atrophied body; therefore, a total pancreatectomy was performed under the diagnosis of multiple pancreatic cancers. The histological analysis revealed fibrosis with dense and diffuse infiltrations of lymphocytes and IgG4-positive plasma cells. The pancreatic parenchyma of the body was firmly replaced by fibrosis. AIP can lead to the formation of multiple pancreatic lesions, and thus the correct diagnosis is occasionally difficult to establish in atypical cases.  相似文献   
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ObjectivesTo investigate the frequency of imatinib-induced pancreatic complications and determine whether these are survival prognostic factors in patients with gastrointestinal stromal tumor (GIST).MethodsThis retrospective multicenter study included patients with histopathologically diagnosed GIST treated with imatinib who underwent computed tomography (CT) within 100 days before (pretreatment CT) and 500 days after (post-treatment CT) imatinib initiation (January 2004–December 2019). Forty-eight patients (63.0 ± 12.1 years, 30 men) were included. Two blinded radiologists independently measured pancreatic volumes. Pancreatic volume on pretreatment CT was compared with that of the control (within 1 year prior to pretreatment CT) and the first two post-treatment CTs using paired t-tests. Thresholds for pancreatic hypertrophy and atrophy were defined using a log-rank test. The prognostic importance of pancreatic hypertrophy was further analyzed using multivariate Cox proportional hazard regression models.ResultsPancreatic volume was significantly higher for the first post-treatment CT than pretreatment CT (71.5 cm3 vs. 67.4 cm3, P = .027), whereas no significant difference was observed between the pretreatment and control CTs. Optimal thresholds for pancreatic hypertrophy and atrophy were defined as an 22% increase and 30% decrease and found in 20 and three patients, respectively. Pancreatic hypertrophy was significantly associated with reduced survival [hazard ratio = 2.9 (95% confidence interval, 1.3–6.5), P = .0088]. No patients showed serum lipase elevation, nor were they suspected of having acute pancreatitis.ConclusionThere was frequent asymptomatic pancreatic swelling in patients with GIST after imatinib treatment, and a ≥22% increase in pancreatic volume was a predictor of reduced survival.  相似文献   
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BackgroundEbola virus disease (EVD) was endemic to Africa in 2014–2016. Supportive therapies have been shown to improve the outcome of EVD, and additional supportive therapy including blood transfusion therapy and external circulation could be needed in the event of a future global outbreak. However, pre-transfusion testing policies and guidelines have not yet been established in Japan.MethodsWe conducted a cross-sectional study of blood transfusion therapy for EVD patients at three designated hospitals for serious communicable diseases in Tokyo. In each hospital, we surveyed blood transfusion therapy policy, blood transfusion protocol, presence of a specialist in the department of transfusion medicine, facility capacity for pre-transfusion compatibility testing, and types of personal protective equipment available.ResultsOne hospital had a cross-matched compatible blood transfusion policy, one had a cross-matched compatible blood transfusion policy only when the patient's ABO and RhD type is previously known, and the third had not created a policy. Two hospitals had a department of transfusion medicine. These two hospitals had a special testing unit for serious communicable diseases, while the other had a portable unit for testing. There were no major differences noted in available personal protective equipment.ConclusionPolicies and protocols differ among hospitals. The choice of blood transfusion policy and pre-transfusion testing is largely dependent on equipment and human resources. Further discussion is required to develop national guidelines for blood transfusion therapy in patients with serious communicable diseases, including countermeasures against complications and ethical issues related to the safety of patients and healthcare workers.  相似文献   
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ObjectivesMalnutrition and inflammation are common in patients with head and neck cancer and are closely associated with prognosis. Although several parameters for evaluating nutritional/inflammatory status have been assessed in relation to the prognosis of patients with head and neck cancer, previous studies primarily included patients with advanced-stage disease. To date, there is no consensus regarding the most reliable parameter for predicting the prognosis of early and advanced-stage head and neck cancer. This study sought to evaluate nutritional/inflammatory prognostic factors before treatment in patients with early and advanced-stage head and neck cancer.MethodsWe retrospectively reviewed medical records of patients treated between 2008 and 2015 at our institution in order to evaluate the effects of nutritional/inflammatory parameters, including C-reactive protein/albumin ratio, modified Glasgow prognostic score, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, and Geriatric Nutritional Risk Index, on overall survival. Effects of potential risk factors on overall survival were analyzed by computing Kaplan-Meier estimates; curves were compared using the log-rank test.ResultsA total of 164 patients were enrolled. C-reactive protein/albumin ratio, modified Glasgow prognostic score, platelet/lymphocyte ratio, and Geriatric Nutritional Risk Index were found to be statistically significantly correlated with overall survival. Only the Geriatric Nutritional Risk Index remained statistically significant in the multivariate analysis. The three-year survival rates according to the four-group Geriatric Nutritional Risk Index scores for normal, low, moderate, and high risk were 95.5%, 84.3%, 53.8%, and 23.4%, respectively.ConclusionThe Geriatric Nutritional Risk Index is therefore a useful prognostic factor for patients with early and advanced-stage head and neck cancer.  相似文献   
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The prognosis of follicular lymphoma (FL) is significantly associated with host immunity and tumor microenvironment. Lymphopenia has been identified as a negative prognostic factor for FL. The association between monocytosis and progression-free survival (PFS) in FL remains controversial. It is unknown whether the ratio of peripheral blood absolute lymphocyte count to absolute monocyte count (ALC/AMC) at diagnosis is associated with FL prognosis. We studied 99 consecutive patients with FL who were treated with rituximab-containing chemotherapy at Kitano Hospital or Kyoto University Hospital between 2000 and 2012. We analyzed individual variables associated with the ALC/AMC ratio before treatment, as well as known prognostic factors of FL, and found that an ALC/AMC ratio of 4.7 was the best cut-off value for PFS. Kaplan–Meier analysis showed that a decreased ALC/AMC ratio was associated with inferior PFS (P = 0.022). Multivariate analysis showed that a decreased ALC/AMC ratio was a significant poor prognostic factor independent of other variables (hazard ratio, 2.714; 95 % confidence interval, 1.060–6.948; P = 0.037). The ALC/AMC ratio before treatment may be a significant prognostic factor predicting PFS of FL.  相似文献   
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