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101.
Urinary cadmium and serum levels of estrogens and androgens in postmenopausal Japanese women. 总被引:1,自引:0,他引:1
Chisato Nagata Yasuko Nagao Chiken Shibuya Yoshitomo Kashiki Hiroyuki Shimizu 《Cancer epidemiology, biomarkers & prevention》2005,14(3):705-708
BACKGROUND: Recent laboratory studies have suggested that cadmium is an estrogenic compound and may be a potential risk factor for breast cancer. METHODS: We investigated the relationship between urinary cadmium concentrations and serum concentrations of estrone, testosterone, and dehydroepiandrosterone sulfate in 164 postmenopausal Japanese women. RESULTS: There was a significant positive association between the urinary cadmium and serum testosterone levels after controlling for age and body mass index. The mean testosterone level was 28% higher in women with high urinary cadmium (> or = 3.00 microg/g creatinine) than in those with low urinary cadmium (< 2.00 microg/g creatinine). Urinary cadmium was not significantly associated with serum estrone and dehydroepiandrosterone sulfate levels. Additional adjustment for smoking, alcohol and reproductive factors including known risk factors for breast cancer did not substantially alter the results. CONCLUSION: Data suggested that cadmium exposure is associated with increased testosterone levels. As high testosterone levels have been associated with the risk of breast cancer, the involvement of cadmium exposure in breast cancer risk should be evaluated in future studies. 相似文献
102.
Elias JJ Nagao M Chu YH Carbone JJ Lennox DW Chao EY 《Clinical orthopaedics and related research》2000,(370):250-258
Intraoperative proximal femur fractures are a significant concern during noncemented total hip arthroplasty. The current study was performed to investigate the hypothesis that broaching the femur and inserting the stem without using mallet applied impact loads will reduce the risk of intraoperative fracture. Rosette strain gauges were applied to the medial and anteromedial cortex of six human anatomic specimen femurs to compare the strain distribution for broaching and stem insertion. Eight additional femurs were used to compare the strain distribution for stem insertion using impact loading and constant rate stem insertion. For the impact loading stem insertions, the soft tissues surrounding the femur were modeled. Constant rate stem insertions were performed using a mechanical testing machine. The largest strains measured at the medial and anteromedial sites primarily were aligned with the femur hoop axis. The largest strain magnitude, orientation, and sign (tensile or compressive) varied widely among femurs. The stem insertion strains were significantly larger than the broaching strains (two-way analysis of variance with replication). The impact stem insertion strains were not significantly different from the constant rate stem insertion strains. The results indicate that the femur geometry and material properties have a greater influence on the strain distribution than does the implantation technique. 相似文献
103.
Yosuke Ando Takahiro Hayashi Kaori Ito Eri Suzuki Naoyuki Mine Ayumi Miyamoto Miyuki Oya Hidezo Matsuda Ami Isaji Toru Nakanishi Kazuyoshi Imaizumi Tomoyuki Shibata Tatsuyoshi Okada Kazuo Sakurai Kensei Naito Ichiro Uyama Kenji Kawada Hiroshi Takahashi Shigeki Yamada 《Supportive care in cancer》2016,24(2):871-878
104.
Kaori Sumida Gen Kashiwaya Shinichiro Seki Takafumi Masui Yoshinori Ando Kikuji Yamashita Akira Fujimura Seiichiro Kitamura 《Clinical anatomy (New York, N.Y.)》2014,27(7):1009-1015
In our ongoing series of anatomical studies to determine the three‐dimensional architecture of the human velar muscles, we have previously reported on the palatopharyngeus. The present study deals with the musculus uvulae (MU), in which the positional relationships of its origin to the posterior nasal spine and the palatine aponeurosis, as well as the interrelation between its anatomical status and functions, have yet to be clarified. Macroscopic and microscopic examinations were performed on 25 and 2 cadavers, respectively. In the former, bilateral MUs and their adjacent structures were exposed mainly from the nasal aspect. In the latter, the soft palates embedded in paraffin were cut into frontal and sagittal sections and alternately processed with HE and Azan stains. The left and right MUs adjacent to each other were found to run longitudinally along the midline beneath the nasal aspect of velum. It was overlaid by glandular tissue that increased in amount as it coursed distally. After originating from the oral surface of palatine aponeurosis, it ran backward to cross above the sling formed by the levator veli palatini muscles of both sides and reached the tip of uvula with its muscle fibers intermingled with glandular tissue. Past studies have proposed three functions of MU to enhance the efficiency of velopharyngeal closure: space occupier, stiffness modifier, and velar extensor. All of the above‐described anatomical characteristics of MU could be explained as being adapted for these functions. This implies that MU is actively responsible for maintaining the velopharyngeal closure efficiency. Clin. Anat. 27:1009–1015, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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108.
Monji Koga Kaori Koga Juichiro Nakayama Shinichi Imafuku 《The Journal of dermatology》2014,41(10):885-889
Neurofibromatosis type 1 (NF1) is a well‐known genetic disorder characterized by café‐au‐lait spots and neurofibromas, but many other clinical characteristics and associated comorbidities also have been reported. This study aimed to characterize NF1 further by investigating its association with anthropometric characteristics and other diseases. We performed a case–control study of 227 NF1 patients (101 male, 126 female) and a randomly selected age‐ and sex‐matched control group of 681 non‐NF1 patients (303 male, 378 female) who visited our institution in Japan. We examined adult (≥20 years) height and body mass index (BMI), and, in the total sample, allergic diseases (bronchial asthma [BA], atopic dermatitis [AD] and allergic rhinitis) and other respiratory cardiovascular and psychiatric disorders. In adults, the mean BMI was lower in the NF1 group than in the control group, and was significantly statistically different among men (P = 0.0238). In the whole sample, the prevalences of BA (P = 0.0184), AD (P = 0.0144) and valvular heart disease (P = 0.0166) were significantly greater in the NF1 group than in the control group. To date, no similar research on the BMI or the prevalence of allergic disease in NF1 patients has been reported. Our results suggest that NF1 patients tend to have lower BMI and may have alterations in specific metabolic pathways and altered allergic immunity. 相似文献
109.
Shou Soeda Kaori Yamada Miho Ohsugi 《Genes to cells : devoted to molecular & cellular mechanisms》2013,18(10):850-858
Mammalian oocytes are arrested at metaphase II due to high MAP kinase activity. After fertilization, oocytes resume meiosis, leading to female chromosome segregation, polar body emission and pronuclear (PN) formation. Previous biochemical studies showed that MAP kinase activity remained high for several hours after fertilization and began to decrease in parallel with PN formation. It has been thought that MAP kinase activity is incompatible with PN formation, and its inactivation is required for the initiation of PN formation in mammalian oocytes. In this study, we revisited this hypothesis by examining MAP kinase activity and PN formation in individual mouse oocytes using cytological analysis. We showed that MAP kinase activity in oocytes could be evaluated using phospho‐ERK1/2 immunofluorescent staining. Co‐immunofluorescent staining of phospho‐ERK1/2 and nuclear pore components showed that PN formation preceded MAP kinase inactivation and could be initiated while MAP kinase activity was still high. Moreover, artificial inactivation of MAP kinase or its downstream target, ribosomal S6 kinase, accelerated but did not rapidly induce PN formation. Our results show that although the MAP kinase pathway negatively regulates PN formation, its inactivation is neither necessary nor sufficient for PN formation. These results suggest the involvement of other essential factor(s) in this process. 相似文献
110.
Kaori Kitaoka Azusa Kitade Junko Nagaoka Kokoro Tsuzaki Kiyomi Harada Wataru Aoi Sayori Wada Hiroaki Asano Naoki Sakane Akane Higashi 《Nutrition Research And Practice》2015,9(4):385-392
BACKGROUND/OBJECTIVESRecent studies have reported an association of the angiotensin II type 2 receptor (AT2R) 3123Cytosine/Adenine (3123C/A) polymorphism with essential hypertension and cardiovascular diseases. The purpose of the study was to investigate whether the AT2R 3123C/A polymorphism affects blood pressure for free-living hypertensive men during a 5-month intervention period.SUBJECTS/METHODSThe subjects were free-living hypertensive Japanese men aged 40 to 75 years who agreed to intervention in the period from 2004 to 2011. Detection of the AT2R 3123C/A polymorphism was determined by polymerase chain reaction. The dietary intervention was designed to decrease salt level and to increase potassium level through cooking instructions and self-monitoring of the diet. The exercise session consisted of activities such as stretching, resistance training, and walking. Blood pressure, urinary sodium and potassium excretion, dietary and lifestyle data, and non-fasting venous blood sample were collected at baseline and after the intervention period.RESULTSThirty nine subjects were eligible for participation and the follow-up rate was 97.4%. The C allele proportion was 57.9%. AT2R 3123C/A polymorphism was X-chromosome-linked, therefore we analyzed the C and A genotypes. At baseline, no significant differences were observed between the genotype groups. After the intervention, there were no significant differences in lifestyle habit between the groups. Nevertheless, the estimated salt excretion (g/day) was significantly decreased only in the C genotype (13.0-10.3, P = 0.031). No significant change was observed in systolic blood pressure (SBP) (mmHg) in the A genotype, but a significant decrease was observed in the C genotype (150.0-141.5, P = 0.024).CONCLUSTIONSIn the C genotype, it might be easy to improve SBP through lifestyle intervention in free-living hypertensive Japanese men, however generalization could not be achieved by the small sample size. 相似文献