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81.
Mitsuhiro Fukao Yuichi Hattori Morio Kanno Ichiro Sakuma Akira Kitabatake 《British journal of pharmacology》1997,120(7):1328-1334
- The aim of the present study was to identify the sources of Ca2+ contributing to acetylcholine (ACh)-induced release of endothelium-derived hyperpolarizing factor (EDHF) from endothelial cells of rat mesenteric artery and to assess the pathway involved. The changes in membrane potentials of smooth muscles by ACh measured with the microelectrode technique were evaluated as a marker for EDHF release.
- ACh elicited membrane hyperpolarization of smooth muscle cells in an endothelium-dependent manner. The hyperpolarizing response was not affected by treatment with 10 μM indomethacin, 300 μM NG-nitro-L-arginine or 10 μM oxyhaemoglobin, thereby indicating that the hyperpolarization is not mediated by prostanoids or nitric oxide but is presumably by EDHF.
- In the presence of extracellular Ca2+, 1 μM ACh generated a hyperpolarization composed of the transient and sustained components. By contrast, in Ca2+-free medium, ACh produced only transient hyperpolarization.
- Pretreatment with 100 nM thapsigargin and 3 μM cyclopiazonic acid, endoplasmic reticulum Ca2+-ATPase inhibitors, completely abolished ACh-induced hyperpolarization. Pretreatment with 20 mM caffeine also markedly attenuated ACh-induced hyperpolarization. However, the overall pattern and peak amplitude of hyperpolarization were unaffected by pretreatment with 1 μM ryanodine.
- In the presence of 5 mM Ni2+ or 3 mM Mn2+, the hyperpolarizing response to ACh was transient, and the sustained component of hyperpolarization was not observed. On the other hand, 1 μM nifedipine had no effect on ACh-induced hyperpolarization.
- ACh-induced hyperpolarization was nearly completely eliminated by 500 nM U-73122 or 200 μM 2-nitro-4-carboxyphenyl-N,N-diphenylcarbamate, inhibitors of phospholipase C, but was unchanged by 500 nM U-73343, an inactive form of U-73122. Pretreatment with 20 nM staurosporine, an inhibitor of protein kinase C, did not modify ACh-induced hyperpolarization.
- These results indicate that the ACh-induced release of EDHF from endothelial cells of rat mesenteric artery is possibly initiated by Ca2+ release from inositol 1,4,5-trisphosphate (IP3)-sensitive Ca2+ pool as a consequence of stimulation of phospholipid hydrolysis due to phospholipase C activation, and maintained by Ca2+ influx via a Ni2+- and Mn2+-sensitive pathway distinct from L-type Ca2+ channels. The Ca2+-influx mechanism seems to be activated following IP3-induced depletion of the pool.
82.
Sakurada I Kido T Suwazono Y Kobayashi E Kinouchi N Nogawa K 《Environmental health and preventive medicine》1999,4(1):30-33
An investigation on the health status of 79 male preparatory school students lodging at a dormitory in Japan was carried out
by questionnaire on lifestyles, subjective symptoms and mental status, as compared with two control groups: 73 medical students
and 36 new employees. About 83 % of them slept less than 6 hours and 70 % of them did not exercise. Many students are troubled
with back pain or lumbago(47%), sensation of incomplete bladder emptying(l6%), loss of visual acuity(55%) and eye fatigue(65%).
Self-rating depression scale score of preparatory school students was not significantly higher than those of the control groups.
The lifestyles of preparatory school students found to be very restricted and strained. However, no significant differences
on mental adverse health effects was found among three groups. 相似文献
83.
Use of ultrasound-guided percutaneous needle biopsy in the diagnosis of mediastinal tumors 总被引:1,自引:0,他引:1
Yoshimi Otani Ichiro Yoshida Susumu Ishikawa Akio Ohtaki Osamu Kawashima Toru Takahashi Yasushi Sato Yasuo Morishita 《Surgery today》1996,26(12):990-992
We herein report the usefulness of ultrasoundguided percutaneous needle biopsy for histological diagnosis in 18 patients with mediastinal tumors. Computed tomography revealed these tumors to be in contact with the chest wall. The preoperative diagnosis was thymoma in 7 patients, germinoma in 5, neurogenic tumor in 3, and other in 3. The most commonly encountered indication for an ultrasound-guided percutaneous needle biopsy was an anterior mediastinal lesion (78%; 14 of 18 patients). In 16 (89%) of the 18 patients, the biopsy diagnosis corresponded to the post-operative diagnosis. No complications were encountered in any of the patients. This new technique of ultrasound-guided percutaneous needle biopsy is both relatively simple and highly accurate and may thus be useful for outpatients. Preoperative ultrasound-guided percutaneous needle biopsy is thus considered to be a safe and reliable method for the histological diagnosis of mediastinal tumors, and a good alternative to traditional biopsy techniques such as mediastinoscopy or thoracotomy.Presented at the 11th Biennial Asian Congress on Thoracic and Cardiovascular Surgery, Kuala Lumpur, Malaysia, November, 21–25, 1993. 相似文献
84.
Ryoichi Sato Ichiro Hisatome Yasunori Tanaka Norito Sasaki Hiroshi Kotake Hiroto Mashiba Ryo Katori 《Naunyn-Schmiedeberg's archives of pharmacology》1991,344(3):331-336
Summary Aprindine is a class Ib antiarrhythmic agent. We studied effects of aprindine (3 µmol/l) on the Na+ current using whole cell voltage clamp (tip resistance = 0.5 , [Na]i ando = 10 mmol/l at 18°C). Aprindine revealed tonic block (Kdrest = 37.7 µmol/l, Kdi = 0.74 µmol/l; n = 4). Aprindine, shifted inactivation curve to hyperpolarizing direction by 11.4 ± 3.5 mV (n = 4) without changes in slope factor. In the presence of 3 µmol/l aprindine, aprindine showed phasic block, i.e., duration-dependent block at 2 Hz (64% ±3070 at 1.5 ms, 82%±6% at 20 ms, 93%±7% at 200 ms; n = 4). Short single prepulse also produced aprindine-induced phasic block (12% at 1.5 ms, 22% at 100 ms; n = 2). After removal of fast inactivation of Na+ current by 3 mmol/l tosylchloramide sodium, aprindine revealed phasic block, independent of holding potential. The recovery time constant from aprindine-induced phasic block was 4.8 s at holding potential = –100 mV and 5.0 s at holding potential = –140 mV. This use-dependent block of aprindine had pH dependency. Under acidic condition (pH 6.0), 3 µmol/l aprindine showed smaller use-dependent block (14% ± 7% at 2 Hz; n = 4) comparing with either at pH 7,4 (68% ± 13%; n = 4) or at pH 8.0 (90% ±12%; n = 4).The results suggest that aprindine could bind to the receptor via activation process through channel pore, resulting in decrease of Na+ current, and egress from the receptor through the lipid bilayer. These effects might be attenuated under acidic condition due to changes in intracellular ratio of charged to neutralized form of drug molecule.
Send offprint requests to: R. Sato at the above address 相似文献
85.
Regulation of p27 by S-phase kinase-associated protein 2 is associated with aggressiveness in non-small-cell lung cancer. 总被引:13,自引:0,他引:13
Atsushi Osoegawa Ichiro Yoshino Shinji Tanaka Kenji Sugio Toshifumi Kameyama Masafumi Yamaguchi Yoshihiko Maehara 《Journal of clinical oncology》2004,22(20):4165-4173
PURPOSE: The F-box protein S-phase kinase-associated protein 2 (Skp2) is one of the positive regulators of the cell cycle that promote ubiquitin-mediated proteolysis of the cyclin-dependent kinase inhibitor p27. In this study, we investigated the significance of Skp2 expression in human non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Clinicopathologic features and immunohistochemical expression of Skp2 and p27 proteins were studied in 138 patients with NSCLC. Survival analyses were performed using the Kaplan-Meier method and the Cox regression model. To analyze the role of Skp2 in vitro, NSCLC cells were transfected with an Skp2-expressing vector or small interfering RNA. RESULTS: Skp2 was overexpressed in males, smokers, patients with squamous cell carcinomas, and patients with poorly differentiated cancers (P = .034, < .0001, < .0001, and .002, respectively). The multivariant analysis revealed that Skp2 expression is an independent prognostic factor for survival in NSCLC. An inverse relationship of Skp2 with p27 expression was observed (P = .012), and patients with both a higher expression of Skp2 and a lower expression of p27 showed a significantly unfavorable prognosis (P = .0002). In vitro ectopic expression of Skp2 in NSCLC cells reduced the protein level of p27. Conversely, induction of Skp2 siRNA increased the protein level of p27, leading to growth inhibition in NSCLC cells. CONCLUSION: Skp2 overexpression is closely associated with the suppression of p27 and the aggressiveness in NSCLC. It also could be a therapeutic target in NSCLC. 相似文献
86.
Functional impact of breast cancer by age at diagnosis. 总被引:5,自引:0,他引:5
Candyce H Kroenke Bernard Rosner Wendy Y Chen Ichiro Kawachi Graham A Colditz Michelle D Holmes 《Journal of clinical oncology》2004,22(10):1849-1856
PURPOSE: To explore changes in physical and psychosocial function before and after breast cancer by age at diagnosis. PATIENTS AND METHODS: A total of 122,969 women from the Nurses' Health Study (NHS) and NHS 2, ages 29 to 71 years, who responded to pre- and postfunctional status assessments were included; 1,082 women were diagnosed with breast cancer between 1992 and 1997. Functional status was measured using the Medical Outcomes Study Short Form 36 (SF-36). Mean change in health-related quality of life (HRQoL) scores was computed across categories representing the combination of incident breast cancer (yes or no) and age at diagnosis (< or = 40, 41 to 64, or 65+ years). RESULTS: Compared with women < or = 40 years without breast cancer, women with breast cancer experienced significant functional declines. Young (age < or = 40) women who developed breast cancer experienced the largest relative declines in HRQoL (as compared with middle-aged and elderly women) in multiple domains including physical roles (-18.8 v -11.5 and -7.5 points, respectively), bodily pain (-9.0 v -2.7 and -2.7 points), social functioning (-11.3 v -4.3 and -4.4 points) and mental health (-3.1 v 0.0 and +0.4 points). Much of the decline in HRQoL among elderly (age > or = 65) women with breast cancer was age related. CONCLUSION: Young women may fare worse than middle-aged or elderly women in both physical and psychosocial dimensions after breast cancer diagnosis. The needs of women facing breast cancer may be better understood within a life stage framework. 相似文献
87.
Pelvic insufficiency fractures in postmenopausal woman with advanced cervical cancer treated by radiotherapy. 总被引:3,自引:0,他引:3
Ichiro Ogino Naoyuki Okamoto Yoshimi Ono Tatsuo Kitamura Hiroki Nakayama 《Radiotherapy and oncology》2003,68(1):61-67
PURPOSE: To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. MATERIAL AND METHODS: A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. RESULTS: Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. CONCLUSIONS: We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight. 相似文献
88.
Reduced MLH1 expression after chemotherapy is an indicator for poor prognosis in esophageal cancers.
Kentaro Kishi Yuichiro Doki Masahiko Yano Takushi Yasuda Yoshiyuki Fujiwara Syuji Takiguchi Sontae Kim Ichiro Higuchi Morito Monden 《Clinical cancer research》2003,9(12):4368-4375
PURPOSE: Loss of function or expression of the mismatch repair gene MLH1 has been implicated in experimentally acquired resistance to cisplatin (CDDP) and other anticancer agents. The clinical significance of MLH1 expression was evaluated in advanced thoracic squamous cell carcinoma of the esophagus (ESCC) treated by neoadjuvant chemotherapy. EXPERIMENTAL DESIGN: We investigated MLH1 and P53 expression by immunohistochemistry in the surgical specimens of 107 patients who had undergone preoperative chemotherapy using CDDP along with 5-FU and ADM. These findings were correlated with the clinical outcome for this treatment. Biopsy samples before chemotherapy in 20 of these patients, and another 43 surgical specimens without chemotherapy, were also examined as control samples. RESULTS: In surgical specimens of ESCC, low MLH1 expression was not frequent without chemotherapy, whereas it was commonly observed after chemotherapy (14 versus 37%, P = 0.0057). Comparison between samples before and after chemotherapy revealed that MLH1 expression was unchanged during chemotherapy in 12 of 20 patients (60%) but was from high to low in 8 of 20 patients (40%). In the surgical specimen after neoadjuvant chemotherapy, MLH1 expression was not correlated with any clinicopathological factors, including the response to chemotherapy. However, low MLH1 showed poorer prognosis than high MLH1 (5-year survival 40.6 versus 19.3%, P = 0.0393), and in multivariate analysis, MLH1 was an independent prognostic factor for this multimodal treatment, following lymph node metastasis and clinical response to chemotherapy. Positive p53 expression, which was not affected by chemotherapy, was weakly associated with a poor response and clinical outcome, although this trend was not significant. CONCLUSIONS: In advanced ESCC, expression of MLH1 is reduced during CDDP-based chemotherapy, and this may partly account for poor postoperative survival. 相似文献
89.
Abul Mokarim Masataka Uetani Ichiro Sakamoto Nobuyuki Hayashi Koichiro Nomata Hiroshi Ohtani 《Acta oncologica (Stockholm, Sweden)》1997,36(2):175-181
Forty-five patients (median age 63 years) with muscle invasive bladder cancer were treated with transcatheter intraarterial infusion (TAI) of cisplatin (CDDP) and doxorubicin. They received a total of 114 courses (median 3 courses per patient) of TAI. Complete response was obtained in 20 patients (44%), partial response in 17 (38%), stable disease in 6(13%), and progression of disease in 2 patients (5%). The overall response rate was 82% at a median follow-up of 36 months. The actuarial survival of the patient population was 72% at 5 years; 36 patients were alive and 9 had died of cancer progression. The treatment was generally extremely well tolerated without major complications. The current study also revealed the fact that papillary carcinomas were more sensitive to this therapy than were non-papillary tumors. Overall, response rate and local control were significantly higher in low-grade than in high-grade tumors. The observed high complete response and good survival rate suggest that intraarterial CDDP and doxorubicin might be highly effective for localized invasive bladder cancer. 相似文献
90.
Nobukazu Fujimoto Yoshihiko Segewa Nagio Takigawa Ichiro Takata Katsuyuki Hotta Hiroshi Mogami Masao Nakata Koichi Mandai Kenji Eguchi 《Lung cancer (Amsterdam, Netherlands)》1998,20(3):203-209
We present two cases of intrapulmonary lymph node. The patients were a 44-year-old woman and a 71-year-old man each with a small peripheral nodule in the lung. On computed tomography (CT) scans, both nodules were spiculated. Since histological diagnosis could not be obtained by bronchoscopic examination or CT-guided needle biopsy, they underwent video-assisted thoracoscopic surgery. Histological examination of the resected material revealed that both nodules were composed of lymph node. Intrapulmonary lymph node has until recently been assigned no clinical significance; however, differential diagnosis of this lesion from lung cancers and other metastatic tumors is now clinically important. 相似文献