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991.
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Secondary clonal hemaloiogical disease in donor cells has rarely been reported as a complication of allogeneic stem cell transplantation in hematological disease. We report a case of myelodysplastic syndrome that showed cytogenetic abnormalities of t(2;3) and monosomy 7, which developed 2 years after peripheral blood stem cell transplantation for aplastic anemia and 1 year after liver transplantation for drug-induced hepatic failure. This secondary malignancy of donor origin is most frequently seen in patients with leukemia. We suspect that the chromosomal abnormalities are related to hepatitis-associated aplastic anemia, administration of granulocyte colony-stimulating factor and erythropoietin for posttransplantion pancytopenia, and repeated infections after liver transplantation.  相似文献   
993.
Neuropeptide Y (NPY) is thought to have a major role in the physiological control of energy homeostasis. Among five NPY receptors described, the NPY Y5 receptor (Y5R) is a prime candidate to mediate some of the effects of NPY on energy homeostasis, although its role in physiologically relevant rodent obesity models remains poorly defined. We examined the effect of a potent and highly selective Y5R antagonist in rodent obesity and dietary models. The Y5R antagonist selectively ameliorated diet-induced obesity (DIO) in rodents by suppressing body weight gain and adiposity while improving the DIO-associated hyperinsulinemia. The compound did not affect the body weight of lean mice fed a regular diet or genetically obese leptin receptor-deficient mice or rats, despite similarly high brain Y5R receptor occupancy. The Y5R antagonist acts in a mechanism-based manner, as the compound did not affect DIO of Y5R-deficient mice. These results indicate that Y5R is involved in the regulation and development of DIO and suggest utility for Y5R antagonists in the treatment of obesity.  相似文献   
994.
Stat3 mediates a complex spectrum of cellular responses, including inflammation, cell proliferation, and apoptosis. Although evidence exists in support of a positive role for Stat3 in cancer, its role has remained somewhat controversial because of insufficient study of how its genetic deletion may affect carcinogenesis in various tissues. In this study, we show using epithelium-specific knockout mice (Stat3(Δ/Δ)) that Stat3 blunts rather than supports antitumor immunity in carcinogen-induced lung tumorigenesis. Although Stat3(Δ/Δ) mice did not show any lung defects in terms of proliferation, apoptosis, or angiogenesis, they exhibited reduced urethane-induced tumorigenesis and increased antitumor inflammation and natural killer (NK) cell immunity. Comparative microarray analysis revealed an increase in Stat3(Δ/Δ) tumors in proinflammatory chemokine production and a decrease in MHC class I antigen expression associated with NK cell recognition. Consistent with these findings, human non-small cell lung cancer (NSCLC) cells in which Stat3 was silenced displayed an enhancement of proinflammatory chemokine production, reduced expression of MHC class I antigen, and increased susceptibility to NK cell-mediated cytotoxicity. In addition, supernatants from Stat3-silenced NSCLC cells promoted monocyte migration. Collectively, our findings argue that Stat3 exerts an inhibitory effect on antitumor NK cell immunity in the setting of carcinogen-induced tumorigenesis.  相似文献   
995.
We investigated in conscious dogs (a) the effects of heart failure induced by chronic rapid ventricular pacing on the sequence of development of left ventricular (LV) diastolic versus systolic dysfunction and (b) whether the changes were load dependent or secondary to alterations in structure. LV systolic and diastolic dysfunction were evident within 24 h after initiation of pacing and occurred in parallel over 3 wk. LV systolic function was reduced at 3 wk, i.e., peak LV dP/dt fell by -1,327 +/- 105 mmHg/s and ejection fraction by -22 +/- 2%. LV diastolic dysfunction also progressed over 3 wk of pacing, i.e., tau increased by +14.0 +/- 2.8 ms and the myocardial stiffness constant by +6.5 +/- 1.4, whereas LV chamber stiffness did not change. These alterations were associated with increases in LV end-systolic (+28.6 +/- 5.7 g/cm2) and LV end-diastolic stresses (+40.4 +/- 5.3 g/cm2). When stresses and heart rate were matched at the same levels in the control and failure states, the increases in tau and myocardial stiffness were no longer observed, whereas LV systolic function remained depressed. There were no increases in connective tissue content in heart failure. Thus, pacing-induced heart failure in conscious dogs is characterized by major alterations in diastolic function which are reversible with normalization of increased loading condition.  相似文献   
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Nakamura K  Yanaka K  Ihara S  Nose T 《Neurosurgery》2003,53(5):1210-4; discussion 1214-5
OBJECTIVE AND IMPORTANCE: The association of Graves' disease with multiple intracranial arterial stenoses is rare. CLINICAL PRESENTATION: We report on two Japanese women who experienced the concurrence of Graves' disease and cerebral ischemia attributable to multiple intracranial arterial stenoses around the circle of Willis. Clinically, these patients demonstrated hyperthyroidism, goiter, ophthalmopathy, and ensuing ischemic strokes. Cerebral angiography demonstrated multiple intracranial arterial stenoses around the circle of Willis in both cases. These cases did not meet the full diagnostic criteria for moyamoya disease, in that there were no abnormal, net-like, collateral vessels, but the other clinical and angiographic findings were consistent with this condition. INTERVENTION: After normalization of their hormonal conditions, the patients underwent cerebral revascularization procedures. Both patients achieved excellent recoveries and returned to normal daily life after treatment. CONCLUSION: Multiple intracranial arterial stenoses and Graves' disease may occur simultaneously. Such cases may offer new insights into the pathogenesis of these two conditions. It is important to study more patients with this dual condition, to obtain more evidence of the relationship between genetic and immunogenic backgrounds.  相似文献   
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