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Multiple lymphomatous polyposis(MLP)is an uncommon type of gastrointestinal lymphoma characterized by the presence of multiple polyps along the gastrointestinal tract.Most of this entity is in fact considered the counterpart of gastrointestinal tract involvement for mantle cell lymphoma(MCL).To our knowledge,there have been no reports on[fluorine-18]-fluorodeoxy-glucose(18F-FDG)-positron emission tomography(PET)/computed tomography(CT)imaging for gastrointestinal MCL with MLP.We present the results of 18F-FDG PET/CT imaging in a patient with gastrointestinal tract involvement of MCL showing continuous MLP from the stomach to the rectum and intestinal intussusception.FDG-PET/CT findings were false negative in typical MLP spreading widely over the gastrointestinal tract,but uptake was noted in large lesions with deep infiltration considered atypical as MLP.On FDG-PET/CT imaging,the Ki-67proliferative index,which is a cell proliferation marker,showed neither correlation with the presence of uptake nor the maximum standardized uptake value.  相似文献   
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Adynamic bone disease in HD patients is characterized by skeletal resistance to parathyroid hormone (PTH) or suppression of PTH release, leading to a downregulated bone turnover and bone fracture. Hence, we examined the efficacy of weekly teriparatide for HD patients with low PTH indicating adynamic bone disease without a history of parathyroidectomy. Fifteen HD patients with low PTH were recruited in this prospective observational study. Of them, 10 received teriparatide for 12 months and five nontreated patients were enrolled as control. Primary outcomes were defined as the changes in bone mineral density and bone turnover markers. Bone mineral density at the lumbar spine increased by 3.7% and 2.5% at 6 and 12 months, respectively, and bone formation markers increased, while bone resorption markers did not change in the teriparatide group. At 12 months after teriparatide administration, endogenous PTH was secreted followed by the recovery of low bone turnover. 40% of patients in the teriparatide group dropped out due to adverse events and the most common adverse event was transient hypotension. This study suggests that weekly teriparatide for HD patients with low PTH in the absence of parathyroidectomy accelerates bone formation and bone turnover, leading to increased trabecular bone mass and secretion of endogenous PTH.  相似文献   
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5-Lipoxygenase catalyzes leukotriene generation from arachidonic acid. The gene that encodes 5-lipoxygenase, Alox5, has been identified in genome-wide association and mouse Quantitative Trait Locus studies as a candidate gene for obesity and low bone mass. Thus, we tested the hypothesis that Alox5(-/-) mice would exhibit metabolic and skeletal changes when challenged by a high-fat diet (HFD). On a regular diet, Alox5(-/-) mice did not differ in total body weight, percent fat mass, or bone mineral density compared with wild-type (WT) controls (P < 0.05). However, when placed on a HFD, Alox5(-/-) gained more fat mass and lost greater areal bone mass vs. WT (P < 0.05). Microarchitectural analyses revealed that on a HFD, WT showed increases in cortical area (P < 0.01) and trabecular thickness (P < 0.01), whereas Alox5(-/-) showed no change in cortical parameters but a decrease in trabecular number (P < 0.05) and bone volume fraction compared with WT controls (P < 0.05). By histomorphometry, a HFD did not change bone formation rates of either strain but produced an increase in osteoclast number per bone perimeter in Alox5(-/-) mice (P < 0.03). In vitro, osteoclastogenesis of marrow stromal cells was enhanced in mutant but not WT mice fed a HFD. Gene expression for Rankl, Pparg, and Cox-2 was greater in the femur of Alox5(-/-) than WT mice on a HFD (P < 0.01), but these increases were suppressed in the Alox5(-/-) mice after 8 wk of treatment with celecoxib, a cyclooxygenase-2 inhibitor. In sum, there is a strong gene by environmental interaction for bone mass when mice lacking the Alox5 gene are fed a HFD.  相似文献   
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This study aimed to develop a criterion for screening high risk elderly using Demura's fall risk assessment chart (DFRA), compared with the Tokyo Metropolitan Institute of gerontology (TMIG) fall risk assessment chart. Participants included 1122 healthy elderly individuals aged 60 years and over (380 males and 742 females) 15.8% of whom had experienced a fall. We assessed fall risk of the elderly by DFRA and TMIG. To develop a criterion for screening high fall risk subjects among community-dwelling elderly, receiver-operating-characteristic (ROC) analysis was conducted using fall experience (separated into the categories of faller and non-faller) and the following fall risk scale scores: (1) TMIG score, (2) DFRA score, and (3) potential for falling score according to the DFRA (summing the scores of three items). In ROC analyses, the area under the ROC curve (AUC) for evaluating the potential for falling gave a value of 0.797 (95% CI=0.759-0.834) which proved better than the evaluation of the overall TMIG (0.654, 95% CI=0.600-0.706) and DFRA scores (0.680, 95% CI=0.633-0.727). Assessment of the potential for falling and fall experience are of benefit in screening for elderly persons deemed to be at a high fall risk. Further examinations based on the prospective data setting will be required.  相似文献   
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Dominant negative form of transforming growth factor beta receptor type II (dnTGFβRII) mice, expressing a dominant negative form of TGFβ receptor II under control of the CD4 promoter, develop autoimmune colitis and cholangitis. Deficiency in interleukin (IL)-12p40 lead to a marked diminution of inflammation in both the colon and the liver. To distinguish whether IL-12p40 mediates protection by the IL-12 or IL-23 pathways, we generated an IL-23p19(-/-) dnTGFβRII strain deficient in IL-23, but not in IL-12; mice were longitudinally followed for changes in the natural history of disease and immune responses. Interestingly, IL-23p19(-/-) mice demonstrate dramatic improvement in their colitis, but no changes in biliary pathology; mice also manifest reduced T-helper (Th)17 cell populations and unchanged IFN-γ levels. We submit that the IL-12/Th1 pathway is essential for biliary disease pathogenesis, whereas the IL-23/Th17 pathway mediates colitis. To further assess the mechanism of the IL-23-mediated protection from colitis, we generated an IL-17A(-/-) dnTGFβRII strain deficient in IL-17, a major effector cytokine produced by IL-23-dependent Th17 cells. Deletion of the IL-17A gene did not affect the severity of either cholangitis or colitis, suggesting that the IL-23/Th17 pathway contributes to colon disease in an IL-17-independent manner. These results affirm that the IL-12/Th1 pathway is critical to biliary pathology in dnTGFβRII mice, whereas colitis is caused by a direct effect of IL-23. (HEPATOLOGY 2012).  相似文献   
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