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101.
Changes in optic nerve head blood flow and retrobular hemodynamics following calcium-channel blocker treatment of normal-tension glaucoma 总被引:2,自引:0,他引:2
Tomita G Niwa Y Shinohara H Hayashi N Yamamoto T Kitazawa Y 《International ophthalmology》1999,23(1):3-10
Background: Because calcium channel blockers reduce vascularresistance, they may have a clinical application in the treatment ofnormal-tension glaucoma (NTG). This study investigates changes inboth the optic disc blood flow and the hemodynamics of retrobulbarvessels in NTG patients after the systemic administration of a calcium channel blocker. Methods: Twelve eyes of 12 NTG patients (meanage 57 6 ± 15.3 years) were examined before and after a 4-weektreatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 × 10 pixel windowplaced on the temporal rim region of the optic disc perfusion map. Byultrasound color Doppler imaging (CDI), we measured the peak systolicvelocity (PSV) and the end diastolic velocity (EDV) of the ophthalmicartery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. Results: After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05).Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA(P <0 .05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. Conclusions: Oral nilvadipine appears to reduce orbital vascular resistance, which consequentlyincreases the optic disc blood flow.
Abbreviations.BP – blood pressure;CRA – central retinal artery;CDI – ultrasound color Doppler imaging;EDV – end diastolic velocity;NPCA – short posterior ciliary arteries located nasal to optic nerve;NTG – normal-tension glaucoma;OA – ophthalmic artery;PP – perfusion pressure;PSV – peak systolic velocity;RI – resistance index;SLDF scanning laser-Doppler flowmetry;TPCA – short posterior ciliary arteries locatedtemporal to optic nerve. 相似文献
102.
Hydroxyamino, nitroso and nitro derivatives of 3-amino-1-methyl-5H-pyrido[4,3-b]indole(Trp-P-2) and 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole(Glu-P-1), mutagens-carcinogens produced on pyrolysis of aminoacids, were synthesized from Trp-P-2 and Glu-P-1. 3-Hydroxyamino-1-methyl-5H-pyrido[4,3-b]indole(N-OH-Trp-P-2) and 2-hydroxyamino-6-methyldipyrido[l,2-a:3',2'-d]imidazole (N-OH-Glu-P-1) were obtained with good yieldsby controlled catalytic reduction of 3-nitro-l-methyl-5H-pyrido[4,3-b]indoleand 2-nitro-6-methyldipyrido[1,2-a:3',2'-d]imidazole. Subsequentoxidation of N-OH-Trp-P-2 and N-OH-Glu-P-1 with -manganese dioxideyielded 3-nitroso-1-methyl-5H-pyrido[4,3-b]indole and 2-nitroso-6-methyldipyrido[1,2-a:3',2'-d]imidazole.All six synthesized compounds were mutagenic to Salmonella typhimuriumTA98 without mammalian activation systems. The mutagenic activitiesof hydroxyamino and nitroso derivatives were identical for bothS. typhimurium TA98 and TA98NR, the nitroreductase deficientstrain. However, nitro derivatives were essentially mutageniconly towards S. typhimurium TA98. 相似文献
103.
Tetsuya Yamada Gaku Ichihara Hailan Wang Xiaozhong Yu Kei-ichiro Maeda Hiroko Tsukamura Michihiro Kamijima Tamie Nakajima Yasuhiro Takeuchi 《Toxicological sciences》2003,71(1):96-103
Although 1-bromopropane has been used in chemical and electronic industries as an alternative to ozone layer-depleting solvents, its toxicity on female reproductive organs has not been fully elucidated. The aim of this experiment was to determine the effect of 1-bromopropane on female reproductive function in rats. Forty female Wistar rats were divided into four equal groups. Each group was exposed daily to 0, 200, 400, or 800 ppm of 1-bromopropane for eight h a day. After exposure for 7 weeks, all rats in the 800-ppm group became seriously ill and were sacrificed during the 8th week. The other dose groups were exposed for 12 weeks. In the 800-ppm group, but not in the other two exposed groups, body weight was significantly less than the control at each time point from 2 to 7 weeks after the beginning of exposure. Tests of vaginal smears showed a significant increase in the number of irregular estrous cycles with extended diestrus in the 400- and 800-ppm groups. Histopathological examination of the ovary showed a significant dose-dependent reduction of the number of normal antral follicles and a decrease in the number of normal growing follicles in the 400-ppm group. No significant change was found in plasma concentrations of LH or FSH in any group when compared with the control. Our results indicate that 1-bromopropane can induce a dose-dependent ovarian dysfunction in nonpregnant female rats associated with disruption in follicular growth process. 相似文献
104.
105.
Takeshi Tominaga Hiroki Koyama Tetsuya Toge Shigeto Miura Keizo Sugimachi Susumu Yamaguchi Koichi Hirata Yasumasa Monden Yasuo Nomura Masakazu Toi Izo Kimijima Shinzaburo Noguchi Hiroshi Sonoo Kazuaki Asaishi Tadashi Ikeda Tadaoki Morimoto Jun Ota Yasuo Ohashi Osahiko Abe 《Journal of clinical oncology》2003,21(6):991-998
PURPOSE: We compared the therapeutic usefulness of doxifluridine (5'-DFUR) alone and a combination of 5'-DFUR plus cyclophosphamide (CPM), both of which are considered effective against advanced and recurrent breast cancer, to determine which treatment is more beneficial as postoperative adjuvant chemotherapy. PATIENTS AND METHODS: A total of 1,131 women with node-positive primary breast cancer were randomly assigned after primary surgery to receive 5'-DFUR alone or 5'-DFUR plus CPM. All patients initially received 5'-DFUR in an oral dose of 1,200 mg/d for 4 weeks, starting 4 weeks after surgery. Chemotherapy was then not given for 2 weeks. Patients in the 5'-DFUR group subsequently received five 4-week cycles of treatment consisting of oral 5'-DFUR (1,200 mg/d) for the first 2 weeks and no chemotherapy for the next 2 weeks. Those assigned to the 5'-DFUR plus CPM group also received oral CPM 100 mg/d for the first 2 weeks and no chemotherapy for the next 2 weeks. Women 50 years or older concurrently received 20 mg/d of tamoxifen for 2 years in both groups. RESULTS: Of the 1,088 eligible women, 546 were assigned to receive 5'-DFUR alone and 542 were assigned to receive 5'-DFUR plus CPM. Overall disease-free survival was significantly better in women who received 5'-DFUR plus CPM than in those who received 5'-DFUR alone (log-rank test, P =.021). Toxic effects occurred in 20.0% of patients (109 of 546) in the 5'-DFUR group and 32.3% of patients (175 of 542) in the 5'-DFUR plus CPM group (chi(2) test, P <.001). CONCLUSION: Combination therapy with 5'-DFUR plus CPM is more effective in preventing recurrence than 5'-DFUR alone. 相似文献
106.
Tetsuya Otani Motoki Iwasaki Seiichiro Yamamoto Tomotaka Sobue Tomoyuki Hanaoka Manami Inoue Shoichiro Tsugane 《Cancer epidemiology, biomarkers & prevention》2003,12(12):1492-1500
Few studies have examined the association of alcohol consumption and cigarette smoking with colorectal cancer in Asian populations whose genetic susceptibility to these factors are different from Western populations. We investigated this association and the joint effect of these factors, and estimated the population-attributable fraction to clarify the public health impact on a Japanese population, based on a prospective study. We analyzed the 10-year (cohort I) and 7-year (cohort II) follow-up data of the Japan Public Health Center-based prospective study on cancer and cardiovascular disease, derived from 90,004 (42,540 male and 47,464 female) middle-aged and elderly Japanese. We identified 716 (457 in men and 259 in women) newly diagnosed cases of colorectal cancer. Both alcohol consumption and smoking were clearly associated with colorectal cancer in men, after adjusting for age, family history of colorectal cancer, body mass index, and physical exercise. Regular heavy drinking of 150 g/week or more of ethanol showed a statistically significant increased risk compared with nondrinkers: relative risks (RRs) were 1.4 [95% confidence interval (CI), 1.1-1.9] for 150-299 g/week and 2.1 (95% CI, 1.6-2.7) for 300 g/week or more. On the contrary, regular ethanol consumption was not associated with colorectal cancer (RR, 0.7; 95% CI, 0.4-1.1) in women. In terms of smoking, the RRs were 1.4 (95% CI, 1.1-1.8) for current smokers and 1.3 (95% CI, 0.98-1.7) for ex-smokers compared with never-smokers in men. The risk of smoking in women was similar to that in men, although not statistically significant. The colorectal cancer risk with 300 g/week or more of ethanol in current smokers was estimated at 3.0 (95% CI, 1.8-5.1) compared with nondrinkers among nonsmokers in men. Colorectal cancer attributable to alcohol consumption or smoking was estimated to be 46%. In conclusion, approximately half of the colorectal cancer cases may be preventable by tobacco and alcohol controls in middle-aged and elderly Japanese men. 相似文献
107.
108.
Satoshi Katsuno Tetsuya Ishiyama Masanori Sakaguchi Hiroki Takemae 《The Laryngoscope》1997,107(5):661-664
Patients with advanced cervical cancers often have direct invasion of their carotid arteries. The prognosis for these patients with nonsurgical therapy is extremely poor. Because complete tumor removal is the only therapy that can offer these patients a chance for cure, carotid resection should be performed. We performed carotid resection and reconstruction on nine patients with advanced cervical cancers. Of these patients, none suffered from severe neurologic postoperative complications such as permanent hemiplegia. Three of the nine patients have been disease free for more than 24 months. These three patients would not have survived without carotid resection. Further study will show the usefulness of carotid resection and reconstruction in decreasing the morbidity and mortality in patients with cervical cancer involving the carotid artery. 相似文献
109.
Shigemi Onoue Takehito Katoh Yoshihisa Shibata Yasushi Mokuno Katsushi Yoshida Satoshi Kamiya Tetsuya Abe Kiyoshi Hiramatsu Minoru Esaki Haruhiko Chigira 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(2):121-124
We report a case of a long-term survivor with malignant melanoma of the anus who did not undergo radical surgery. A 71-year-old
woman who presented with anal bleeding and anal tumor underwent an excisional biopsy in September 1985. The biopsy specimen
was a lobulated, polypoid, pigmented mass 2 cm in diameter, that had been located on the anterior wall of the anus. A satellite
nodule 7 mm in diameter was found on the left wall of the anus at the level of the dentate line. Both tumors were histologically
diagnosed as malignant melanoma. The primary tumor was 6 mm thick. Melanoma cells were present microscopically at the cut
end of the rectum. Because of her history of ischemic heart disease, the patient rejected our recommendation that she undergo
radical surgery, and received 10 courses of carboplatin 20 mg intramuscularly and OK-432 10 K.E. (Klinische Einheit) intradermally
every week. A single, pigmented metastatic inguinal lymph node developed and was excised in June 1987. A recurrent tumor was
detected in the rectum in October 1992, so again we recommended radical surgery. The patient rejected radical surgery again,
and received 12 courses of carboplatin 10 mg intramuscularly every 2 weeks. She died of disease at home in July 1993 after
surviving for 7 years and 10 months. An autopsy was not performed. This case shows that local excision of the primary lesion
may be appropriate to preserve the quality of life of patients with early-stage malignant melanoma of the anus. 相似文献
110.
Tetsuya Shirokawa Yoshiyuki Ishida Wataru Matsunaga Sadamu Nakai Ken-ichi Isobe 《Nihon shinkei seishin yakurigaku zasshi》2005,25(1):43-48
The locus coeruleus (LC), located within the caudal pontine central gray, is composed of noradrenaline-containing neurons. The axons of these neurons form extensive collateral branches that project widely to many brain sites. The function of the LC is still unclear at present, however, LC neurons are known to exhibit marked axonal regeneration and sprouting in response to brain damage. We investigated the age-related changes in noradrenergic innervations of the frontal cortex, using in vivo electrophysiological techniques and immunohistochemistry. While noradrenergic innervations gradually decreased with age in the frontal cortex, a high degree of sprouting occurred in the LC axon terminals in middle age. Neither the electrophysiological properties of LC neurons nor NA levels in the frontal cortex changed with age. These findings suggested that the LC neurons preserve a strong capacity to remodel their axon terminals even in the aging brain. Exogenous brain-derived neurotrophic factor (BDNF) infusion caused a marked increase in the density of noradrenergic axon in the aged brain, but no trophic action of BDNF was observed in the young or middle-aged brain. The result suggests that BDNF is necessary for the maintenance of noradrenergic innervations in the aged brain. 相似文献