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91.
Both radiation and stresses cause detrimental effects on humans. Besides possible health effects resulting directly from radiation exposure, the nuclear plant accident is a cause of social psychological stresses. A recent study showed that chronic restraint-induced stresses (CRIS) attenuated Trp53 functions and increased carcinogenesis susceptibility of Trp53-heterozygous mice to total-body X-irradiation (TBXI), having a big impact on the academic world and a sensational effect on the public, especially the residents living in radioactively contaminated areas. It is important to investigate the possible modification effects from CRIS on radiation-induced health consequences in Trp53 wild-type (Trp53wt) animals. Prior to a carcinogenesis study, effects of TBXI on the hematopoietic system under CRIS were investigated in terms of hematological abnormality in the peripheral blood and residual damage in the bone marrow erythrocytes using a mouse restraint model. Five-week-old male Trp53wt C57BL/6J mice were restrained 6 h per day for 28 consecutive days, and TBXI (4 Gy) was given on the 8th day. Results showed that CRIS alone induced a marked decrease in the red blood cell (RBC) and the white blood cell (WBC) count, while TBXI caused significantly lower counts of RBCs, WBCs and blood platelets, and a lower concentration of hemoglobin regardless of CRIS. CRIS alone did not show any significant effect on erythrocyte proliferation and on induction of micronucleated erythrocytes, whereas TBXI markedly inhibited erythrocyte proliferation and induced a significant increase in the incidences of micronucleated erythrocytes, regardless of CRIS. These findings suggest that CRIS does not have a significant impact on radiation-induced detrimental effects on the hematopoietic system in Trp53wt mice.  相似文献   
92.
BackgroundDealing with chemotherapy-related cardiac dysfunction (CTRCD) remains a significant problem complicated by the difficulty in early detection of cardiotoxicity. Electrocardiogram (ECG) is expected to be the most realistic methodology due to lower cost-performance and non-invasiveness. We investigated the long-term visual fluctuations in the ECG waveforms in patients with chronic doxorubicin (DOX)-induced cardiotoxicity to identify ECG indices for the early detection of cardiotoxicity.MethodsWe conducted a retrospective case series study by reviewing the medical records of 470 consecutive patients with malignant lymphoma who were treated with DOX at our institute between January 2010 and December 2017. Of them, 23 (4.9%) patients developed left ventricular dysfunction and were diagnosed with CTRCD using echocardiography. We assessed the ECG indices on 12-lead ECG recordings before and after treatment in 15 patients; eight patients were excluded due to conduction disturbances or atrial fibrillation.ResultsCTRCD was detected at a median of 475 (interquartile range, IQR: 341–1333) days after initiating chemotherapy. The evaluation of ECG indices preceding CTRCD development was performed 93 (IQR: 52–232) days before the detection of CTRCD. In the stage of CTRCD, the most significant ECG change was T-wave flattening in leads V3–V6 (12 patients, 80%). Additionally, QTa prolongation was observed in leads I and aVL (n = 10, 66%), leads II, III, and aVF (n = 9, 60%), and leads V3–V6 (n = 10, 73%). These ECG changes were not observed before the treatment but were detected mildly in the pre-CTRCD stage, which subsequently worsened in the CTRCD stage.ConclusionsThis study indicated that T-wave changes and QTa prolongation may be useful as an early indicator before the onset of CTRCD in patients with DOX-induced cardiotoxicity.  相似文献   
93.
Journal of Gastroenterology - This multicenter prospective study (UMIN000019958) aimed to evaluate the usefulness of serum leucin-rich alpha-2 glycoprotein (LRG) levels in monitoring disease...  相似文献   
94.
BACKGROUND AND AIM: The authors have previously shown that production of interleukin (IL)-18 was increased in the inflamed mucosa of patients with Crohn's disease (CD) and blockade of IL-18 ameliorated the murine model of CD. This demonstrated that IL-18 plays a significant role during intestinal inflammation. However, the initial role of IL-18 during intestinal inflammation was unclear; therefore the susceptibility of IL-18 transgenic (Tg) mice to acute dextran sulfate sodium (DSS)-induced colitis was examined. METHODS: Interleukin-18 Tg and wild-type (WT) mice were fed 2.0% of DSS for 8 days. The total clinical scores (bodyweight loss, stool consistency, and rectal bleeding), colon length and histological scores were assessed. The expressions of surface markers and IL-18 on infiltrating lamina propria mononuclear cells were analyzed immunohistochemistrically. Mesenteric lymph node (MLN) cells were isolated and the expressions of CD4+ T-cell activation markers (CD69, CD25 and IL18R) were analyzed by flow cytometry. RESULTS: The IL-18 Tg mice exhibited an increased susceptibility to DSS-induced colitis, as shown by significantly increased clinical, histological scores, and more severe colonic shortening compared with WT mice. Immunohistochemical analysis revealed a significant increase of IL-18 production and CD11b+ macrophages but not CD4+ T cells in the inflamed mucosa in DSS-fed IL-18 Tg compared with DSS-fed WT mice. Furthermore, MLN cells revealed no evidence of increased CD4+ T-cell activation in DSS-fed IL-18 Tg. CONCLUSIONS: These findings suggest that IL-18 overproduction in the mucosa plays an important role in the marked infiltration of macrophages and exacerbates colitis in IL-18 Tg mice.  相似文献   
95.
Annals of Nuclear Medicine - Amyloid positron emission tomography (PET) can reliably detect senile plaques and fluorinated ligands are approved for clinical use. However, the clinical impact of...  相似文献   
96.
97.
BACKGROUND: A prospective study examined whether a combination of an exercise program and heparin administration improves the clinical symptoms of patients with arteriosclerosis obliterans (ASO) without an indication for surgical revascularization because of the lack of distal target vessels or other reasons such as high surgical risk or lack of a vein conduit from previous coronary artery bypass surgery. METHODS AND RESULTS: A total of 19 consecutive patients with symptomatic non-option ASO diagnosed by angiography were randomly assigned to 3 groups: heparin + exercise (walking for 60 min after heparin injection [3,000 units/day IV for 14 days], n = 6), heparin administration only (n = 6), and exercise only (n = 7). Plasma levels of hepatocyte growth factor (HGF) were serially measured before and after intravenous administration of heparin. Ankle brachial pressure index was measured and treadmill exercise test (2.5 km/h, 12% slope) was performed before the 2-week treatment, just after finishing treatment, and 12 weeks after beginning the treatment. Ophthalmic examinations, including visual acuity test, ocular fundoscopy and fluorescein angiographic fundus photography, were performed before and 12 weeks after the treatment program. In all patients, HGF levels increased more than 4-fold of the basal level at 30 min after heparin injection. Maximum walking time was significantly higher in the heparin + exercise group than in the other 2 groups (p < 0.05). There were no patients who showed pathological retinal angiogenesis. CONCLUSION: The combination of an exercise program and heparin administration improves the clinical symptoms of patients with non-option ASO.  相似文献   
98.
Incidence of human parvovirus B19 DNA detection in blood donors   总被引:2,自引:0,他引:2  
Summary. 1000 serum samples from blood donors were tested for human parvovirus B19 (B19) DNA by a nested PCR assay: six samples were positive for B19 DNA. The frequency was 1/167 (0-6%), considerably higher than previous surveys (0-004-0-03%). Five of the six samples were also positive for anti-B19 IgM, indicating an acute phase of infection. It is recommended to screen for B19 DNA in blood products to prevent transfusion mediated viral infection for those susceptible such as immunocompromised patients and pregnant women.  相似文献   
99.
Nonenzymatic glycosylation of plasma proteins may contribute to the excess risk of developing atherosclerosis in patients with diabetes mellitus. Although it is believed that high-density lipoprotein (HDL) is glycosylated at an increased level in diabetic individuals, little is known about a possible linkage between glycated HDL and endothelial dysfunction in diabetes. To clarify whether glucose-modified HDL affects the function of endothelial cells, we first examined herein the level of H(2)O(2) generation from cultured human aortic endothelial cells (HAECs) exposed to a glycated oxidized HDL (gly-ox-HDL) prepared in vitro. Incubation for 48 hours with 100 microg/mL of gly-ox-HDL induced significant release of H(2)O(2) from cells and gly-ox-HDL-induced H(2)O(2) formation was inhibited in the presence of diphenyleneiodonium, an inhibitor of NADPH oxidase. In addition, stimulation of HAECs with gly-ox-HDL for 48 hours elicited a marked downregulation of catalase and Cu(2+), Zn(2+)-superoxide dismutase (CuZn-SOD), suggesting H(2)O(2) formation by gly-ox-HDL to be due to a disturbance involving oxidant and antioxidant enzymes in the cells. Treatment of HAECs with gly-ox-HDL attenuated the expression of endothelial nitric oxide synthase (eNOS), but not inducible nitric oxide synthase (iNOS), and this was followed by decreased production of nitric oxide (NO) by the cells. Furthermore, in vitro experiments with glycated HDL (gly-HDL) in the presence of 2 mmol/L EDTA and Cu(2+)-oxidized HDL suggested the effect of gly-HDL on endothelial function to be possibly potentiated by additional oxidative modification. Taking all of the above findings together, gly-ox-HDL may lead to the deterioration of vascular function through altered production of reactive oxygen species and reactive nitrogen species in endothelial cells.  相似文献   
100.
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