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71.
Clinical and Experimental Nephrology - We investigated whether butyrylcholinesterase (BChE) was independently related to the overall survival (OS) of patients on maintenance hemodialysis (MHD)....  相似文献   
72.
Reproducibility of corrected QT interval (QTc), especially QTc after exercise, has not been thoroughly investigated. We reviewed charts of pediatric patients who underwent treadmill‐exercise stress testing without medication multiple times within 1 year. In patients with long‐QT syndrome (LQTS; n = 22), the discrepancy in QTc between two treadmill exercise stress tests using Fridericia's formula was 14 ± 12 ms at rest, 13 ± 12 ms 4 min after exercise, with a maximum of 14 ± 12 ms after exercise. There was no statistically significant difference in QTc between the two tests. Intraclass correlation coefficients (ICC) were 0.84, 0.85, and 0.85, respectively. In controls (n = 13), the discrepancy in QTc was 18 ± 12 ms at rest, 14 ± 7 ms 4 min after exercise, with a maximum of 14 ± 9 ms after exercise. There was no significant difference in QTc between the two tests. ICC were 0.78, 0.80, and 0.80, respectively. QTc calculated using Bazett's formula also showed high reproducibility. Reproducibility of QTc in children is high at rest and after exercise.  相似文献   
73.
Hyponatremia is the most common clinical electrolyte disorder. Once thought to be asymptomatic in response to adaptation by the brain, recent evidence suggests that chronic hyponatremia may be linked to attention deficits, gait disturbances, risk of falls, and cognitive impairments. Such neurologic defects are associated with a reduction in quality of life and may be a significant cause of mortality. However, because underlying diseases such as adrenal insufficiency, heart failure, liver cirrhosis, and cancer may also affect brain function, the contribution of hyponatremia alone to neurologic manifestations and the underlying mechanisms remain unclear. Using a syndrome of inappropriate secretion of antidiuretic hormone rat model, we show here that sustained reduction of serum sodium ion concentration induced gait disturbances; facilitated the extinction of a contextual fear memory; caused cognitive impairment in a novel object recognition test; and impaired long-term potentiation at hippocampal CA3–CA1 synapses. In vivo microdialysis revealed an elevated extracellular glutamate concentration in the hippocampus of chronically hyponatremic rats. A sustained low extracellular sodium ion concentration also decreased glutamate uptake by primary astrocyte cultures, suggesting an underlying mechanism of impaired long-term potentiation. Furthermore, gait and memory performances of corrected hyponatremic rats were equivalent to those of control rats. Thus, these results suggest chronic hyponatremia in humans may cause gait disturbance and cognitive impairment, but these abnormalities are reversible and careful correction of this condition may improve quality of life and reduce mortality.  相似文献   
74.

Background

We previously demonstrated validation of the Comprehensive International Classification of Functioning, Disability and Health Core Set for Diabetes Mellitus (ICF-CS for DM) in patients with diabetic nephropathy (DMN). The objective of the present study was to identify differences in experience of physical and psychosocial problems between DMN patients with and without hemodialysis (HD), and diabetes patients without nephropathy using the ICF-CS for DM.

Methods

A total of 302 diabetes outpatients (men, 68 %; mean age, 62 years) were interviewed using four components of the ICF-CS for DM including “Body functions”, “Body structures”, “Activities and participation”, and “Environmental factors”.

Results

The mean number of categories in which difficulty was experienced in the four components was significantly greater in DMN patients with HD followed by DMN patients without HD, and diabetes patients without nephropathy (23.9 vs. 18.0 vs. 13.1, respectively). Multivariate logistic regression models revealed that, compared with diabetes patients without nephropathy, diabetes patients with nephropathy were more likely to have difficulty with physical problems and social activities and participation. Among DMN patients, dialysis patients were found to have larger numbers of problems, and face difficulty with employment status after adjusting for sex, age, type, and duration of diabetes.

Conclusion

The results of this study using the ICF-CS for DM identified the areas for improvement among physical and psychosocial problems in DMN patients with and without HD in contrast to diabetes patients without nephropathy.
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Vascular calcification (VC) is a life-threatening complication of CKD. Severe protein restriction causes a shortage of essential amino acids, and exacerbates VC in rats. Therefore, we investigated the effects of dietary l-lysine, the first-limiting amino acid of cereal grains, on VC. Male Sprague-Dawley rats at age 13 weeks were divided randomly into four groups: low-protein (LP) diet (group LP), LP diet+adenine (group Ade), LP diet+adenine+glycine (group Gly) as a control amino acid group, and LP diet+adenine+l-lysine·HCl (group Lys). At age 18 weeks, group LP had no VC, whereas groups Ade and Gly had comparable levels of severe VC. l-Lysine supplementation almost completely ameliorated VC. Physical parameters and serum creatinine, urea nitrogen, and phosphate did not differ among groups Ade, Gly, and Lys. Notably, serum calcium in group Lys was slightly but significantly higher than in groups Ade and Gly. Dietary l-lysine strongly suppressed plasma intact parathyroid hormone in adenine rats and supported a proper bone-vascular axis. The conserved orientation of the femoral apatite in group Lys also evidenced the bone-protective effects of l-lysine. Dietary l-lysine elevated plasma alanine, proline, arginine, and homoarginine but not lysine. Analyses in vitro demonstrated that alanine and proline inhibit apoptosis of cultured vascular smooth muscle cells, and that arginine and homoarginine attenuate mineral precipitations in a supersaturated calcium/phosphate solution. In conclusion, dietary supplementation of l-lysine ameliorated VC by modifying key pathways that exacerbate VC.Medial vascular calcification is common in aging, diabetes, and CKD.14 Because the presence of vascular calcification is strongly associated with increased cardiovascular morbidity and mortality, several studies in both animals and humans have sought ways to reduce the extent of vascular calcification.510 However, satisfactory therapies have not yet been established.11Adenine-induced renal failure is one of the commonly used animal models for studying the development of vascular calcification, but the prevalence of vascular calcification in this model is not very high. Indeed, Price et al. reported that vascular calcification was detected in only 30% of rats with adenine-induced chronic renal failure (adenine rats) fed a normal-protein diet.5 These authors speculated that consistent vascular calcification might require a longer period of adenine feeding. On the basis of this idea, they designed a low-protein (LP) diet in an attempt to reduce the nitrogen load and thus enable the rats to thrive on the adenine diet for longer periods. As a result of this attempt, Price et al. unexpectedly found that adenine rats fed a LP diet had extensive vascular calcification without a longer feeding period.5 All 13 adenine rats fed the LP diet had uniform alizarin red staining of the aorta, whereas only 3 of the 11 adenine rats fed a normal-protein diet had partial calcification.5 These findings indicated that dietary protein deficiency correlates with the extent of vascular calcification.Proteins are usually made from 20 kinds of amino acids. On the basis of nutritional requirements, these amino acids can be divided into two groups: essential amino acids (EAAs) and non-EAAs. Because restriction of dietary protein results in a shortage of EAAs, the level of dietary EAAs may be relevant to the extent of vascular calcification. Among nine EAAs, this study focused on l-lysine (l-Lys) based on the following three reasons. First, l-Lys is the first-limiting amino acid in most cereal grains.12 Second, the safety of l-Lys supplementation has been verified in the area of animal husbandry. l-Lys has long been added to feed grains in order to improve the utility of feed proteins.13 Third, several studies have demonstrated that dietary supplementation with l-Lys protects bones from osteoporosis, a pathologic condition that often coexists with vascular calcification.14,15 These points prompted us to hypothesize that supplementation with l-Lys would ameliorate vascular calcification. Therefore, in this study, we tested this hypothesis using adenine rats.  相似文献   
78.
A Case of Extragenital Choriocarcinoma in the Jejunum   总被引:2,自引:0,他引:2  
A case of extragenital choriocarcinoma which produces human chorionic gonadotropin (HCG) in the small intestine of a 48-yr-old Japanese women is reported. Only seven such cases have been reported. The patient complained of postprandial upper abdominal pain and vomiting of 5 months' duration. Nine years before, right upper lobectomy was performed because of lung undifferentiated carcinoma. Double-contrast examination of the small intestine showed irregular ulceration in the lower jejunum. Celiac angiography demonstrated a hypervascular tumor stain in the branch of the jejunal artery. The serum HCG level was elevated. Gynecological examination revealed nothing abnormal. A small intestinal neoplasm was diagnosed, and a partial resection of the jejunum was performed. Endoscopy on the operating table showed a large, irregularly shaped sessile ulcer. Histologically the tumor was diagnosed as choriocarcinoma, composed of syncytiotrophoblastic cells and cytotrophoblastic cells. Immunohistochemical staining for HCG was positive. No metastasis was present. Although extragenital choriocarcinoma in the small intestine is rare, it should be included in the differential diagnosis of small intestinal neoplasm.  相似文献   
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The envelope proteins of the hepatitis C virus (HCV), E1 and E2, have been revealed to be essential for invasion of HCV. Thus, we were engaged in the search for the inhibitors against HCV invasion through the assay system using the model virus expressing recombinant HCV envelopes, E1 and E2. Now, we disclosed dimeric hydrolysable tannin oenothein B (1) from MeOH extract of Oenothera erythrosepala as an active principle for inhibition of HCV invasion and its potency was almost the same as that of monomeric hydrolysable tannin, tellimagrandin I (2). Furthermore, by use of stereoselectively prepared 1-β- and 1-α-O-methyl tellimagrandin Is (4 and 5), the introduction of methyl moiety into 1-hydroxy group of 2 was clarified to result in slightly reduction of activity and β-isomer was revealed to exhibit a little stronger activity than α-one.

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