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91.
Carnosine (beta-alanyl-L-histidine) and its derivative anserine (beta-alanyl-1-methyl-L-histidine) are antioxidants and putative neurotransmitters in the brain. These dipeptides are rich in the commercially available supplement chicken breast extract (CBEX). To clarify the effects of CBEX on the brain, we examined whether single oral administration of CBEX (20 ml/kg) affects brain dipeptide and free amino acid concentrations in male Wistar rats. CBEX significantly and time-dependently increased carnosine and anserine levels in the plasma (at 120 min after injection, increase rates were 2976 and 4142%, respectively), hippocampus (64 and 78%), and hypothalamus (188 and 120%), but not in cerebral cortex. Significant and time-dependent increases in citrulline in the hippocampus (49%) and hypothalamus (41%) demonstrated generation of nitric oxide due to the increased carnosine and/or anserine levels in these brain regions. These findings suggest that CBEX modifies brain functions by increasing levels of these dipeptides.  相似文献   
92.
The in vitro and in vivo activities of a new rifamycin derivative, KRM-1648, against Mycobacterium tuberculosis H37Rv were compared with those of rifampin. Bactericidal activity was evaluated by using a silicone-coated slide culture method. The MBC of KRM-1648 was 0.15 to 0.3 microgram/ml for 24 h of exposure, while that of rifampin was > 160 microgram/ml under the same conditions. Against experimental murine tuberculosis, KRM-1648 exhibited significant therapeutic effects, in terms of prolonged survival times for mice compared with those with rifampin treatment, even at lower doses, such as 1 and 3 mg/kg. At a dose of 3 mg/kg, KRM-1648 was at least as effective as rifampin at 10 mg/kg. The combination of KRM-1648 (3 mg/kg) plus isoniazid (3 mg/kg) plus ethambutol (10 mg/kg) exhibited much more activity than did rifampin (10 mg/kg) plus isoniazid (3 mg/kg) plus ethambutol (10 mg/kg). These findings suggest that KRM-1648 is a promising candidate for the treatment of tuberculosis.  相似文献   
93.
Background:   Although age is a prognostic factor in multiple myeloma (MM), the prognostic factors in elderly MM patients may be different to those in nonelderly MM patients due to the patient's age. The difference in the significance of prognostic factors between elderly MM patients and the nonelderly MM patients was studied.
Methods:   Forty-two elderly MM patients aged 65 years or older were compared with 68 nonelderly MM patients, who were less than 65 years of age. The characteristics of the elderly patients included: aged 65–81 years (median, 72 years); female/male ratio of 22 : 20; 24 IgG type cases, 13 IgA type cases, one non-secretory case and four cases of Bence-Jones type; one case of stage I, 12 cases at stage II and 29 cases at stage III. The prognostic factors were evaluated by means of univariate analysis and Cox's multivariate analysis.
Results:   The median survival time was significantly shorter in the elderly MM patients (24 months) than in the nonelderly patients (50 months) ( P  < 0.01). Of the univariate prognostic factors, corrected serum Ca (cCa), hemoglobin, serum P, bone marrow plasma cell and uric acid were significant prognostic factors in the elderly MM patients, while nine factors including those listed here, were significant in nonelderly controls. Multivariate analysis showed that serum cCa was the only independent prognostic factor ( P  = 0.019) in elderly MM patients, while serum P and bone lesions were significant prognostic factors in nonelderly MM patients.
Conclusion:   Corrected serum c. (cCa) was an independent prognostic factor in elderly MM patients.  相似文献   
94.
95.
Clinical Oral Investigations - The association between salivary flow rate (SFR) and depressive symptoms have been inconclusive. The present study aimed to investigate the association between SFR...  相似文献   
96.
Many elderly patients with pneumonia have aspiration pneumonia. Therefore they must temporarily abstain from oral intake. However, it is difficult to predict whether or not they will be able to start oral intake. The reason is the standard method to evaluate deglutition about pneumonia patients has not been established. In this study we aimed to develop a simple and convenient method that predicts the prognosis of oral intake as nutrition among elderly patients with acute stage pneumonia. Participants were 77 inpatients fasting due to aspiration risk with acute pneumonia. (86.0 ± 7.7 years; range 68–105 years; men: n = 34, women: n = 43) during September 2011 and August 2013. Their consciousness levels were determined by Glasgow coma scale (GCS) and swallowing function and cough reflex were evaluated by repetitive saliva swallowing test (RSST), modified water swallow test, simple swallowing provocation test and cough test. Oral intake status at discharge was considered as the objective variable, and these tests were considered as explanatory variables. Then receiver operating characteristic (ROC) curve and the area under the curve (AUC) for each was done. From the ROC curve analysis, GCS ≥14 had the largest AUC (0.79) with a sensitivity and specificity of 0.71 and 0.80. That was followed by RSST ≥1, AUC (0.77) with a sensitivity and specificity of 0.81 and 0.67. These results suggest that GCS and RSST could be useful screening tests for prognostic prediction of oral intake capability in elderly patients with acute pneumonia.  相似文献   
97.
98.
In order to develop small-diameter vascular grafts, it is necessary to evaluate endothelialization, especially, in the center part at early stage. For implantation of vascular grafts of 1 cm in length to abdominal aortae of rat, endothelial cells can be formed easily by stretching anastomosis. We evaluated the endothelialization in the center part of vascular grafts by implanting vascular grafts using transgenic (TG) silk fibroin (SF) of 3 cm in length. Vascular grafts were prepared 1.5 mm in diameter and 1 and 3 cm in length using wild type (WT) SF and TG SF by braiding structure, respectively. The grafts were removed after 2 weeks or 3 months and evaluated pathologically. Endothelialization was not confirmed totally after 3 months of implantation. However, endothelialization in the center part of grafts was significantly higher in TG SF than in WT SF. No significant difference was found regarding tissue infiltration and internal diameter. The TG SF revealed migration of the endothelial cells into the center part of the vessels at the early stage. Also, tissue infiltration and remodeling is expected using SF. The 3 cm length vascular grafts can be evaluated as a new experimental system.  相似文献   
99.
Natural killer T cells (NKT cells) are comprised of several subsets. However, the possible differences in their developmental mechanisms have not been fully investigated. To evaluate the dependence of some NKT subpopulations on nuclear factor-κB-inducing kinase (NIK) for their generation, we analysed the differentiation of NKT cells, dividing them into subsets in various tissues of alymphoplasia (aly/aly), a mutant mouse strain that lacks functional NIK. The results indicated that the efficient differentiation of both invariant NKT (iNKT) and non-iNKT cells relied on NIK expression in non-haematopoietic cells; however, the dependence of non-iNKT cells was lower than that of iNKT cells. Especially, the differentiation of CD8+ non-iNKT cells was markedly resistant to the aly mutation. The proportion of two other NKT cell subsets, NK1.1+ γδ T cells and NK1.1 iNKT cells, was also significantly reduced in aly/aly mice, and this defect in their development was reversed in wild-type host mice given aly/aly bone marrow cells. In exerting effector functions, NIK in NKT-αβ cells appeared dispensable, as NIK-deficient NKT-αβ cells could secrete interleukin-4 or interferon-γ and exhibit cytolytic activity at a level comparable to that of aly/+ NKT-αβ cells. Collectively, these results imply that the NIK in thymic stroma may be critically involved in the differentiation of most NKT cell subsets (although the level of NIK dependence may vary among the subsets), and also that NIK in NKT-αβ cells may be dispensable for their effector function.  相似文献   
100.
Portopulmonary hypertension (P-PHT) is sporadically found in cirrhosis patients who have portal hypertension. We retrospectively investigated the clinical features of six patients with P-PHT and compared their hemodynamics and arterial oxygenation with data from 60 cirrhosis patients without pulmonary hypertension (non-PHT cirrhosis) admitted to our department. The mean pulmonary artery pressure and pulmonary vascular resistance index of P-PHT patients ranged from 25 to 57mmHg and from 399 to 1405dynesscm(-5)m(-2), respectively, and their arterial oxygenation was impaired. The systemic vascular resistance and cardiac index of P-PHT patients were similar level to those of patients with non-PHT cirrhosis. We found 10 patients with non-PHT cirrhosis in whom pulmonary vascular resistance exceeded the critical level for pre-capillary pulmonary hypertension (120dynesscm(-5)). These patients showed a distinctive hemodynamic profile, including a decrease of cardiac output due to contraction of the plasma volume and resultant elevation of systemic vascular resistance. However, the decrease of cardiac output contributed little to the elevation of pulmonary vascular resistance. Our findings suggested that certain factor(s) were acting to raise pulmonary vascular tone in these patients, which might cause chronic damage to the pulmonary vascular bed, leading to the onset of pulmonary hypertension.  相似文献   
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