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101.
The possible mechanism of the underlying nephropathy found in the rat toxicity study of FYX-051, a xanthine oxidoreductase inhibitor, was investigated. Rats received oral treatment of either 1 or 3 mg/kg of FYX-051, with and without citrate for four weeks to elucidate whether nephropathy could be caused by materials deposited in the kidney. Furthermore, analysis of the renal deposits in rats was also performed. Consequently, interstitial nephritis comprising interstitial inflammatory cell infiltration, dilatation, basophilia and epithelial necrosis of renal tubules and collecting ducts, deposits in renal tubules and collecting ducts, and so forth was seen in six of the eight rats and in all eight rats in the 1 and 3 mg/kg FYX-051 alone groups, respectively, with the intensity in the 3 mg/kg group being moderate to severe. In the simultaneous treatment with citrate group, however, no alterations were observed in the kidney, except for minimal interstitial nephritis in one instance in the 3 mg/kg FYX-051 + citrate group along with an increased urinary pH, leading to an increase in xanthine solubility. Analysis of intrarenal deposits showed that the entity would be composed of xanthine crystals. The present study, therefore, showed that nephropathy in rats occurring after the administration of FYX-051 was a secondary change caused by xanthine crystals being deposited in the kidney, and no other causes could be implicated in this kidney lesion.  相似文献   
102.
PURPOSE: We present results of patients with hepatocellular carcinoma (HCC) treated with proton beam therapy. EXPERIMENTAL DESIGN: We reviewed 162 patients having 192 HCCs treated from November 1985 to July 1998 by proton beam therapy with or without transarterial embolization and percutaneous ethanol injection. The patients in the present series were considered unsuitable for surgery for various reasons, including hepatic dysfunction, multiple tumors, recurrence after surgical resection, and concomitant illnesses. The median total dose of proton irradiation was 72 Gy in 16 fractions over 29 days. RESULTS: The overall survival rate for all of the 162 patients was 23.5% at 5 years. The local control rate at 5 years was 86.9% for all 192 tumors among the 162 patients. The degree of impairment of hepatic functions attributable to coexisting liver cirrhosis and the number of tumors in the liver significantly affected patient survival. For 50 patients having least impaired hepatic functions and a solitary tumor, the survival rate at 5 years was 53.5%. The patients had very few acute reactions to treatments and a few late sequelae during and after the treatments. CONCLUSIONS: Proton beam therapy for patients with HCC is effective, safe, well tolerable, and repeatable. It is the useful treatment mode for either cure or palliation for patients with HCC irrespective of tumor size, tumor location in the liver, insufficient feeding of the tumor with arteries, presence of vascular invasion, impaired hepatic functions, and coexisting intercurrent diseases.  相似文献   
103.
Natural killer (NK) cell-type lymphoproliferative diseases of granular lymphocytes can be subdivided into aggressive NK cell leukemia (ANKL) and chronic NK cell lymphocytosis (CNKL). One reason for the poor outcome in ANKL is leukemic infiltration into multiple organs. The mechanisms of cell trafficking associated with the chemokine system have been investigated in NK cells. To clarify the mechanism of systemic migration of leukemic NK cells, we enrolled nine ANKL and six CNKL cases, and analyzed the expression profiles and functions of chemokine receptors by flowcytometry and chemotaxis assay. CXCR1 was detected on NK cells in all groups, and CCR5 was positive in all ANKL cells. Proliferating NK cells were simultaneously positive for CXCR1 and CCR5 in all ANKL patients examined, and NK cells with this phenotype did not expand in CNKL patients or healthy donors. ANKL cells showed enhanced chemotaxis toward the ligands of these receptors. These results indicated that the chemokine system might play an important role in the pathophysiology of ANKL and that chemokine receptor profiling might be a novel tool for discriminating ANKL cells from benign NK cells.  相似文献   
104.
L-leucine, an essential amino acid, is one of the most popular ingredients in dietary supplements. To investigate a possibility of its embryo-fetal toxicity in rats, 11- to 12-week old dams were orally administered an aqueous solution of L-leucine at doses of 300 or 1000 mg/kg body weight on gestational days 7-17. Body weight and feed intake was evaluated throughout the whole course of pregnancy (days 0-20). L-Leucine did not influence body weight, but at a dose of 1000 mg/kg, slightly enhanced feed intake on days 14 and 18 of pregnancy. Caesarean section (day 20) revealed no influences on the litter size and weight of live-born fetuses, the number of corpora lutea, implantation index or the quality of placenta, and the minor increase in feed intake was considered irrelevant to the pregnancy outcomes. Fetuses were evaluated in a battery of external, visceral and skeletal examinations. No effects of L-leucine on gender ratio and external abnormalities, and no significant treatment-related variations in visceral and skeletal pathologies were observed. These results suggested that L-leucine, administered orally during organogenesis at doses up to 1000 mg/kg body weight, did not affect the outcome of pregnancy and did not cause fetotoxicity in rats.  相似文献   
105.

Background  

Neuromyelitis optica (NMO) is a recurring inflammatory neurological disease characterized by severe optic neuritis and myelitis. The purpose of this study was to determine whether the retinal nerve fiber layer thickness (RNFLT) is correlated with the clinical presentations in patients with NMO and to determine the clinical factors that lead to poor visual outcomes.  相似文献   
106.
Objectives: To clarify the clinical risk factors associated with poor neonatal outcomes due to umbilical cord prolapse (UCP).

Methods: A postal questionnaire survey was attempted in Japan. The clinical risk factors and managements associated with poor neonatal outcomes were analyzed in cases of UCP treated in Japan.

Results: A total of 267 cases of UCP (out of 2?037?460 total deliveries) were analyzed. The rates of intrauterine death, neonatal death and survival with disability were 3.4%, 5.6% and 7.1%, respectively. The multivariate regression analysis for these poor neonatal outcomes revealed that the significant risk factors included a prolapsed amniotic sac (adjusted odds ratio (aOR), 4.49), preterm labor (aOR, 2.99) and replacement of the prolapsed umbilical cord into the uterus (aOR, 2.87). However, UCP that occurred during labor (aOR, 0.28) and emergency cesarean section (aOR, 0.11) were associated with a reduction in the rates of poor outcomes. The interval between the diagnosis of UCP and delivery was significantly longer in the infants with a poor outcome than intact survival (median 30 versus 24?min, p?=?0.048).

Conclusion: An emergency cesarean section should be carried out immediately to ensure a better outcome for the infant.  相似文献   
107.
Anastomotic leakage (AL) after colorectal surgery is a serious complication. This study aimed to evaluate the effectiveness of the EEA™ circular stapler, a new triple-row circular stapler (TCS), relative to a conventional, double-row circular stapler (DCS).A total of 285 patients who underwent anastomosis with the double stapling technique at the Tokyo Medical University Hospital between 2017 and 2021 were included in this nonrandomized clinical trial with historical controls using a propensity score (PS) analysis. The primary endpoint was the risk of AL.We performed a 1:2 PS matching analysis. Before case matching, AL occurred in 15 (7.4%) and 2 (2.4%) patients in the DCS and TCS groups, respectively, with no significant difference (P = .17). After case matching, AL occurred in 13 patients (11.6%) and 1 patient (1.8%) in the DCS and TCS groups, respectively, revealing a significant difference (P = .04). Cox models were created by applying PS to adjust for group differences via regression adjustment. Odds ratios for AL in the DCS group versus the TCS group were 0.31 (95% confidence interval [CI]: 0.07–1.38) in the entire cohort, 0.15 (95% CI: 0.02–0.64) in the regression adjustment cohort, and 0.14 (95% CI: 0.02–1.09) in the 1:2 PS-matched cohort.PS analysis of clinical data suggested that the use of TCS contributes to a reduced risk of AL after colorectal anastomosis CTwith the double stapling technique.  相似文献   
108.
109.
1. Effects of three compounds which are used as calmodulin inhibitors (trifluoperazine, W-7 and calmidazolium) on Ca2+ channels were investigated in smooth muscle from rat vas deferens. 2. All three calmodulin inhibitors relaxed the smooth muscle precontracted by a high concentration of KCl (63.7 mM). The order of potency for the relaxation was trifluoperazine > W-7 > calmidazolium. 3. In binding studies using a microsomal fraction of vas deferens, all these calmodulin inhibitors displaced specific [3H]-nimodipine binding. Trifluoperazine and W-7 inhibited the binding at concentrations that relaxed the smooth muscle whereas calmidazolium inhibited at concentrations much lower than those necessary for muscle relaxation. 4. Ba2+ current flowing through voltage-gated Ca2+ channels was measured under whole-cell voltage-clamp conditions in isolated smooth muscle cells. The Ba2+ current was suppressed by the three calmodulin inhibitors in the concentration-range where inhibition of [3H]-nimodipine binding was observed. Neither voltage-dependence nor the inactivation time course of Ba2+ current were affected by these compounds. 5. The results suggest that the calmodulin inhibitors directly block Ca2+ channels in the smooth muscle cells. The channel inhibition by trifluoperazine and W-7, but perhaps not that by calmidazolium, may be responsible for the muscle relaxation observed with these compounds.  相似文献   
110.
Purpose Hypertension, one of the more common chronic diseases affecting the elderly, has been reported to influence leukocyte–endothelial cell interaction. The leukocyte-mediated inflammatory process contributes to age-related changes in vessels. This study was designed to evaluate age-related changes in leukocyte–endothelial cell interaction in the hypertensive rat retina. Methods Male spontaneous hypertensive rats (SHR; 1.5, 3, 6, 12, and 20 months of age) and age-matched Wistar-Kyoto rats (WKY) were used. The number of accumulated leukocytes was counted in sections of flat-mounted retinal tissue. The expression of intercellular adhesion molecule-1 (ICAM-1) and CD18 (the common β-chain of ICAM-1 ligands) was evaluated. Retinal thickness was evaluated histologically. Results The number of accumulated leukocytes and the expression of ICAM-1 and CD18 increased in the aged retina. The number of leukocytes that accumulated and the expression of CD 18 were significantly higher in the SHR group than in the WKY group (P < 0.01). In addition, retinal thickness decreased with age. Conclusion Leukocyte–endothelial cell interaction increased in the aged retina and these changes were more severe in SHR retina than in WKY retina. This increased interaction was first observed at 3 months, a relatively young age.  相似文献   
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