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991.
Kawamoto K Nagano M Kanda F Chihara K Shigeyoshi Y Okamura H 《Journal of neuroscience research》2003,74(6):852-857
Vasoactive intestinal peptide (VIP) neurons constitute a large group in the suprachiasmatic nucleus (SCN) and it is thought that they are involved in the generation and entrainment of circadian rhythm. We have characterized these VIP-expressing neurons in rat SCN by their ability to induce the mammalian Period1 (Per1) gene in response to light exposure, innervation of retinal afferents, day-night variations in VIP mRNA, and coexpression of gastrin releasing peptide (GRP). VIP neurons in the ventrolateral SCN (SCNVL) were subdivided into two groups, light-evoked Per1-inducible main SCNVL (SCNVLmain) and non-Per1-inducible medially located SCNVL (SCNVLmed). Retinal innervation was abundant in the SCNVLmain but nearly absent in the SCNVLmed. Day-night variation in VIP mRNA expression level was observed in the SCNVLmain but not in the SCNVLmed. GRP mRNA was seen in rarely SCNVLmed but abundant in SCNVLmain, where some neurons coexpressed VIP mRNA. These findings indicate that VIP neurons in the SCN can be divided into two topographically and functionally distinct groups. 相似文献
992.
Response properties of nociceptors in the rat's temporomandibular joint (TMJ) were investigated using an in vitro TMJ-nerve preparation. Recordings were obtained from 33 nociceptive units that responded to mechanical, chemical, and/or thermal stimuli. According to both characteristics of nociceptors and afferent fibers, nociceptive units in the TMJ area were classified into the following four subtypes: Adelta-high-threshold mechanonociceptor (HTM) (12.1%), Adelta-polymodal nociceptor (POLY) (36.4%), C-HTM (12.1%), and C-POLY (39.4%). The mean mechanical threshold of the Adelta units was significantly lower than that of the C units. Bradykinin increased the discharge of Adelta- and C-POLY units. No significant differences of thermal thresholds between Adelta and C units were found. The percentage of Adelta units was 47.2% and of C units was 52.8%, respectively. In the TMJ area, POLY units were predominant (75.8%), suggesting that inflammatory reactions can easily evoke pain sensation. 相似文献
993.
994.
Lee JE Nakagawa T Kim TS Iguchi F Endo T Dong Y Yuki K Naito Y Lee SH Ito J 《The Laryngoscope》2003,113(6):994-999
OBJECTIVES/HYPOTHESIS: The survival of the spiral ganglion (SG) is a critical issue in preservation of hearing. Research on topics related to this issue requires a mouse experimental model because such a model has advantages including use of genetic information and knockout or "knockin" mice. Thus, the aim of the study was to establish a mouse model for induction of apoptosis of SG neurons with a definite time course. STUDY DESIGN: Laboratory study using experimental animals. METHODS: C57BL/6 mice were used as experimental animals and were subjected to direct application of cisplatin into the inner ear. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay and immunostaining for Neurofilament 200-kD (NF) and peripherin were used for analysis of SG degeneration. In addition, generation of peroxynitrite in affected spiral ganglions was examined by immunostaining for nitrotyrosine. Cellular location of activated caspase-9 and cytochrome-c in dying SG neurons were examined for analysis of cell death pathway. RESULTS: The TUNEL assay and immunohistochemical analysis for NF and peripherin indicated that type I neurons in spiral ganglions were deleted through the apoptotic pathway over time. Spiral ganglion neurons treated with cisplatin exhibited expression of nitrotyrosine, indicating induction of peroxynitrite by cisplatin. In dying SG neurons, expression of activated caspase-9 and translocation of cytochrome-c from mitochondria to cytoplasm were observed, indicating the mitochondrial pathway of apoptosis. CONCLUSION: The predictable fashion of induction of apoptosis in SG neurons over a well-defined time course in the model in the study will aid studies of the molecular mechanism of cell death and elucidation of a strategy for prevention of SG degeneration. 相似文献
995.
The potency of ambient air for DNA-adduct formation was estimated using Wistar rats. The animals were maintained in a small-animal facility located beside a main highway intersection in Kawasaki City, Japan, for up to 60 weeks and were exposed to roadside air contaminated mainly with automobile emission (exposure group, EG) or to clean air (control group, CG). Compared to CG, the relative adduct levels (RAL) were increased significantly in EG lungs (17.1-fold (P<0.05)), nasal mucosa, and livers after exposure for 4 weeks. However, there were no significant differences in RAL between EG and CG after exposure for 12 weeks, but they were elevated again in EG after exposure for 48 or 60 weeks. These results suggest that roadside air in this region can cause the generation of DNA adducts. This activity of ambient roadside air can be estimated using experimental animals, indicating that biological monitoring of DNA-adduct formation may be a powerful tool to assess the effect of ambient air on human health. 相似文献
996.
We analyzed the characteristics of 120 patients of primary lung cancer supposed to be induced by exposure to asbestos. Most of 120 patients were male and the age ranged from 47 to 87 years with a median of 70 years. No particular tendency was observed in the histological types of the lung cancer in 120 patients. Forty of the 120 patients were heavy smokers. When the occupational history was analyzed, most of the patients had been exposed to asbestos in former Japanese naval shipyard, commercial shipyards, construction industry and ironworks. The term of asbestos exposure was 2 to 60 years with a median 27 years. Lung cancers appeared after 15 to 69 years with a median 43 years from the initial exposure to asbestos. Lung cancer was accompanied by asbestosis in 35 patients and by pleural plaques in 77. Twenty-two patients had both asbestosis and pleural plaques. The number of asbestos bodies per 5 g wet lung tissue for 72 patients whose lung tissues obtained from autopsy or surgery was more than 150 bodies which meant the number of occupational asbestos exposure. As for the kinds of asbestos fibers of 32 patients, 14 patients exposed to crocidolite, 10 patients to amosite and 8 patients to chrysotile. 相似文献
997.
Kuriki K Nagaya T Tokudome Y Imaeda N Fujiwara N Sato J Goto C Ikeda M Maki S Tajima K Tokudome S 《The Journal of nutrition》2003,133(11):3643-3650
A cross-sectional study was conducted to clarify the associations of lifestyle factors (habitual exercise, alcohol intake and smoking habit) and plasma fatty acid (FA) concentrations as biomarkers of dietary FA intakes. We collected 7-d weighed diet records, lifestyle information and blood samples from 15 male and 79 female Japanese dietitians, and estimated dietary FA intakes and analyzed plasma FA concentrations. Plasma concentrations of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and (n-3) highly unsaturated FA (HUFA) derived from marine foods, but not linoleic and alpha-linolenic acid from plant origins, demonstrated positive correlations with dietary intakes (r = 0.303-0.602, P < 0.05) in both genders. Multiple linear regression analyses adjusted for age, BMI, total energy intake, fat (or respective FA) consumption and lifestyle factors showed that dietary intakes of EPA, DHA and (n-3) HUFA were positively associated with age in men (P < 0.05) and negatively associated with BMI in women [P < 0.01 for DHA and (n-3) HUFA]. The plasma concentrations of EPA, DHA and (n-3) HUFA in women were found to be positively associated with age and marine oil (or respective FA) intake (P < 0.01), and negatively associated with total energy intake [P < 0.05 for EPA and (n-3) HUFA]. Lifestyle factors were not associated with dietary FA intakes and plasma FA concentrations. These findings suggest that the plasma concentrations of EPA, DHA and (n-3) HUFA might be useful biomarkers for the assessment of relative FA intakes without considering associations with habitual exercise, alcohol intake and smoking habit. 相似文献
998.
Toyokawa S Nishikawa H Ueji M Motegi K Kano K 《Environmental health and preventive medicine》2001,6(1):41-46
Several factors have been reported as risk factors for the development of osteoporosis. In this study, we aimed to examine
the relationship among lifestyle factors, biologic factors, and bone mineral density (BMD) using structural equation modeling
(SEM). The subjects in the present study consisted of 866 postmenopausal Japanese women aged between 40 and 80 years old.
In the analysis by the SEM, we employed a multiple basic model. As the structural variables, lifestyle factors and biologic
factors were selected.
The goodness of fit index (GFI) of the final model was 0.991 and the Akaike’s information criteria (AIC) showed the lowest
value in the peripheral models. The degree of association between biologic factors and BMD was −0.576 (direct association),
0.012 (indirect association), and −0.564 (total association). With regard to the correlation between lifestyle factors and
BMD, the degrees of association were 0.085, −0.084, and 0.001, respectively.
This study defined a pilot model for factors influencing BMD. Although is remains necessary to conduct further analyses with
more valid measurements and constructs, this model indicated that the correlation between BMD and lifestyle factors was lower
than that between BMD and biologic factors. 相似文献
999.
Toda M Morimoto K Nakamura S Umeda T Nakaji S Sugawara K 《Environmental health and preventive medicine》2001,6(2):82-87
The purpose of this study was to investigate the effect of weight reduction on the anti-mutagenicity of human saliva. Subjects
were 16 male college judo players. The anti-mutagenicity of the saliva was measured using the umu test. There was an inhibiting
effect of the saliva on the mutagenicity of AF-2. However, a modifying effect of the saliva on Trp-P-1 was not observed. On
the day before a competition and 7 days after the competition, the inhibiting capacity of the saliva for the mutagenicity
of AF-2 decreased and increased in two non-weight reduction and two weight reduction groups, respectively.
However, on the day before the competition, the changed body weights (r=−0.77, p<0.01) and BMI (r=−0.77, p<0.01) were significantly
correlated with that of the inhibiting capacity of the saliva for the mutagenicity of AF-2. In addition, the BMI at 20 days
before the competition was not significantly but markedly correlated with it (r=0.50, p=0.057). At 7 days after the competition,
however, these correlations were not found.
These findings suggest a unique correlation between the anti-mutagenicity of human saliva and body weight or BMI. 相似文献
1000.
Komoriyama H Tanaka I Ikezawa H Kanasugi K Hagiwara M Yamaguchi S 《Drugs of today (Barcelona, Spain : 1998)》2001,37(3):151-158
Low-molecular-weight protease inhibitors were synthesized and developed in Japan and are in clinical use there for the treatment of acute pancreatitis. However, protease inhibitors are not acknowledged as drugs for the treatment of pancreatitis in other countries. In a recent study in 30 patients with necrotizing pancreatitis, survival rate was improved (mortality rate 13.3%) by continuous intraarterial administration of low-molecular-weight protease inhibitors as compared to conventional treatment. In Italy it was reported that pancreatic disorder decreased after the administration of low-molecular-weight protease inhibitors before the start of endoscopic retrograde cholangiopancreatography. Low-molecular-weight protease inhibitors may be potential alternative drugs for the treatment and/or prevention of acute pancreatitis and, therefore, warrant further evaluation. (c) 2001 Prous Science. All rights reserved. 相似文献