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101.
Masseter activity patterns during chewing, which were quantitatively assessed using T50 values, were compared between the right and left sides of healthy young males. Surface electromyograms were recorded from both masseters, and each participant was asked to chew four different agar samples at his own pace across two separate sessions. The four agar samples, each possessing differing textural properties, consisted of two normal and two distinctive agar varieties. The Pearson’s correlation coefficient was calculated for each pair of T50 values to evaluate the degree of synchronization of activity patterns between both masseters. A three-way analysis of variance revealed significant main effects of the ‘participant’ and ‘experimental session’ factors, but not of the ‘test food’. The number of significant coefficients increased stepwise by increasing the number of chews per sequence. These results suggest the importance of the initial stages of chewing sequences in facilitating the synchronization of bilateral masseter activity patterns.  相似文献   
102.
The amounts of sorbitol (SOR) excreted in 24-h urine were determined on two groups, i.e., diabetic and nondiabetic patients, using an improved method in which ion exchange resin column processing was applied, and these levels were compared with SOR levels in whole blood. Urinary SOR concentration was also determined in diabetic and normal rats in the same manner and its relationship to aldose reductase (AR) activity in whole blood was investigated. Changes in SOR levels in urine and whole blood were compared in diabetic rats after administration of an AR inhibitor (ARI). Whole blood SOR levels and urinary SOR excretion were significantly higher in diabetic patients than in nondiabetic patients. The same results were obtained in the animal models. In diabetic rats, the urinary SOR excretion was about five times higher than that in control rats, and the AR activity in whole blood was also significantly higher. The increase in urinary SOR excretion and whole blood SOR levels, as well as AR activity, in blood in the diabetic state was inhibited by ARI administration. The influence of the diabetic state and the efficacy of the ARI were more marked in urinary SOR excretion than in whole blood SOR levels. These data indicate that determinations of urinary SOR excretion and AR activity are easily measurable and of benefit to assessing the diabetic condition.  相似文献   
103.

Background

IgG4-related disease (IgG4-RD) is a novel clinical disease entity characterized by elevated serum IgG4 concentration and tumefaction or tissue infiltration by IgG4+ plasma cells. Although IgG4-RD is not rare and is clinically important, its clinical diagnostic criteria have not been established. Comprehensive diagnostic criteria for IgG4-RD, including the involvement of various organs, are intended for the practical use of general physicians and nonspecialists.

Methods

Two IgG4-RD study groups, the Umehara and Okazaki teams, were organized by the Ministry of Health, Labor and Welfare Japan. As IgG4-RD comprises a wide variety of diseases, these groups consist of physicians and researchers in various disciplines, including rheumatology, hematology, gastroenterology, nephrology, pulmonology, ophthalmology, odontology, pathology, statistics, and basic and molecular immunology throughout Japan, with 66 and 56 members of the Umehara and Okazaki teams, respectively. Collaborations of the two study groups involved detailed analyses of clinical symptoms, laboratory results, and biopsy specimens of patients with IgG4-RD, resulting in the establishment of comprehensive diagnostic criteria for IgG4-RD.

Results

Although many patients with IgG4-RD have lesions in several organs, either synchronously or metachronously, and the pathological features of each organ differ, consensus has been reached on two diagnostic criteria for IgG4RD: (1) serum IgG4 concentration >135?mg/dl, and (2) >40% of IgG+ plasma cells being IgG4+ and >10?cells/high powered field of biopsy sample. Although the comprehensive diagnostic criteria are not sufficiently sensitive for the diagnosis of type 1 IgG4-related autoimmune pancreatitis (IgG4-related AIP), they are adequately sensitive for IgG4-related Mikulicz??s disease (MD) and kidney disease (KD). In addition, the comprehensive diagnostic criteria, combined with organ-specific diagnostic criteria, have increased the sensitivity of diagnosis to 100% for IgG4-related MD, KD, and AIP.

Conclusion

Our comprehensive diagnostic criteria for IgG4-RD are practically useful for general physicians and nonspecialists.  相似文献   
104.
Objective In this study, we investigated whether and how the COVID-19 pandemic affected glycemic control and blood pressure (BP) control in patients with diabetes mellitus (DM). Methods DM patients whose HbA1c level was measured regularly before and after the declaration of a state of emergency were included in this study. Some patients were given questionnaires about changes in their lifestyle to determine the factors affecting glycemic control and BP control. Results The median HbA1c level of the 804 patients increased significantly from 6.8% before the state of emergency to 7.1% and 7.0% during and after the state of emergency, respectively. This was in contrast to the decrease one year earlier due to seasonal variations. In the 176 patients who responded to the questionnaire, the HbA1c level also increased significantly during and after the state of emergency. The worsening of glycemic control was more pronounced in the group that had achieved HbA1c of <7% before the state of emergency than in those with higher values. Unlike the rise in HbA1c, the BP did not rise during the state of emergency but did rise significantly afterwards. There was no marked decrease in HbA1c or BP after the state of emergency, even in patients who responded that they were much more careful with their diet, ate less, or exercised more. Conclusions The COVID-19 pandemic worsened glycemic control and BP control, even in patients who perceived no marked change in their diet or exercise, suggesting that more active lifestyle guidance is necessary for good treatment of DM patients.  相似文献   
105.
Subtotally nephrectomized rats were found to have decreased activities of superoxide dismutase (SOD), catalase and glutathione peroxidase, and spin-trapping with 5,5-dimethyl-1-pyrroline-N-oxide showed that the amount of hydroxyl radical (·OH) in the residual kidney tissue was greater than that in the normal kidney. In contrast, rats given ginseng saponin (25 mg/kg body weight) orally for 30 days after subtotal nephrectomy showed restoration of catalase activity to almost a normal level. A significant increase in SOD activity was observed. ·OH, which is highly reactive and for which there is no scavenger system in the body, was decreased markedly in kidney homogenates obtained from rats given ginseng saponin. The increased levels of uraemic toxins in the blood were also reduced in rats given ginseng saponin. These findings indicate that ginseng saponin helps to inhibit the progression of renal failure by scavenging radicals.  相似文献   
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108.
State‐dependent modulation of sensory systems has been studied in many organisms and is possibly mediated through neuromodulators such as monoamine neurotransmitters. Among these, dopamine is involved in many aspects of animal behaviour, including movement control, attention, motivation and cognition. However, the precise neural mechanism underlying dopaminergic modulation of behaviour induced by sensory stimuli remains poorly understood. Here, we used Drosophila melanogaster to show that dopamine can modulate the optomotor response to moving visual stimuli including noise. The optomotor response is the head‐turning response to moving objects, which is observed in most sight‐reliant animals including mammals and insects. First, the effects of the dopamine system on the optomotor response were investigated in mutant flies deficient in dopamine receptors D1R1 or D1R2, which are involved in the modulation of sleep‐arousal in flies. We examined the optomotor response in D1R1 knockout (D1R1 KO) and D1R2 knockout (D1R2 KO) flies and found that it was not affected in D1R1 KO flies; however, it was significantly reduced in D1R2 KO flies compared with the wild type. Using cell‐type‐specific expression of an RNA interference construct of D1R2, we identified the fan‐shaped body, a part of the central complex, responsible for dopamine‐mediated modulation of the optomotor response. In particular, pontine cells in the fan‐shaped body seemed important in the modulation of the optomotor response, and their neural activity was required for the optomotor response. These results suggest a novel role of the central complex in the modulation of a behaviour based on the processing of sensory stimulations.  相似文献   
109.
BACKGROUND: Some studies focusing on low-risk profiles for cardiovascular disease have been reported in Western countries. Yet, few reports have examined, with substantial longevity, the low-risk profile for cardiovascular disease in the Japanese population. This study examines whether having a favorable risk factor profile yields lower all-cause mortality and whether the proportion of those with a low-risk profile is larger in the Japanese population. METHODS AND RESULTS: A total of 8,339 men and women aged 30-69 years without a history of cardiovascular diseases for 19 years, who had participated in the 1980 National Survey on Circulatory Disorders after being randomly selected from throughout Japan, were followed. Low risk was defined as having all of the following baseline characteristics: blood pressure (BP) <120/80 mmHg; no antihypertensive medication; serum cholesterol 160-240 mg/dl (4.14-6.22 mmol/L); no history of diabetes; and non-smoker. The long-term mortality of the low-risk group was compared with that of others using the Cox proportional hazard model. The prevalence of low risk was 9.4% of all participants. The multivariate-adjusted hazard ratios for low-risk individuals compared with others were as follows: 0.33 (95% confidence intervals (CI), 0.15-0.74) for cardiovascular disease and 0.63 (95% CI, 0.46-0.88) for all-cause mortality. The most attributable risk factor for all-cause mortality was high BP (>or=120/80 mmHg). CONCLUSION: Japanese individuals with favorable cardiovascular disease risk profiles had lower mortality from cardiovascular disease and all-causes than those without.  相似文献   
110.
Two distinct pathways of p16 gene inactivation in gallbladder cancer   总被引:1,自引:0,他引:1  
AIM: TO examine the mechanism of inactivation of the p16 gene in gallbladder cancer, and to investigate p16 alterations and their correlation with clinicopathological features.
METHODS: Specimens were collected surgically from 51 patients with gallbladder cancer. We evaluated the status of protein expression, loss of heterozygosity(LOH), homozygous deletion and promoter hypermethylation using immunohistochemistry, microsatellite analysis, quantitative real-time polymerase chain reaction (PCR) and methylation-specific PCR, respectively. In addition, mutations were examined by direct DNA sequencing.
RESULTS: Homozygous deletions of the p16 gene exon2, LOH at 9p21-22, p16 promoter hypermethylation, and loss of p16 protein expression were detected in 26.0% (13/50), 56.9% (29/51), 72.5% (37/51) and 62.7% (32/51), respectively. No mutations were found. LOH at 9p21 correlated with the loss of p16 protein expression (P 〈 0.05). Homozygous deletion of the p16 gene, a combination LOH and promoter hypermethylation, and multiple LOH at 9p21 were significantly correlated with the loss of p16 protein expression (P 〈 0.05). LOH at 9p21 and promoter hypermethylation of the p16 gene were detected in 15.4% (2/13) and 92.3% (12/13) of the tumors with homozygous deletion of the p16 gene, respectively. P16 alterations were not associated with clinicopathological features.
CONCLUSION: Our results suggest that LOH and homozygous deletion may be two distinct pathways in the inactivation of the p16 gene. Homozygous deletion, a combination of LOH and promoter hypermethylation, and multiple LOH are major mechanisms of p16 inactivation in gallbladder cancer.  相似文献   
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