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131.
Masato Ando Yuhzo Nakashima Yutaka Nagata 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1990,13(1-2):33-46
We examined the effect of GM1-ganglioside in combination with cholera toxin B, and synthetic α-sialyl cholesterol (α-SC) on neutral amino acid (tritiated α-aminoisobutyric acid, [3H]AIB) uptake, protein synthesis ([3H]leucine incorporation), and Na+, K+-ATPase activity in isolated superior cervical ganglia (SCG) and nodose ganglia (NG) from adult rats after aerobic incubation, usually for 2 h at 37°C in vitro. Cholera toxin B, that specifically masks the oligosaccharide chain of GM1-ganglioside, antagonized the GM1-induced changes in [3H]AIB uptake, [3H]leucine incorporation, and Na+, K+-ATPase activity almost completely in SCG, but partially in NG. Although cholesterol itself had little effect on either [3H]AIB uptake and Na+, K+-ATPase activity both in SCG and NG, α-SC caused considerable reduction of both amino acid uptake and the transport enzyme activity in each ganglia. However, cholesterol was more effective than α-SC in decreasing [3H]leucine incorporation in either ganglia. Whereas addition of EGTA markedly reduced either GM1-induced or α-SC-induced change in [3H]leucine incorporation into acid-insoluble fraction in both SCG and NG, application of Ca2+ ionophore produced considerable recovery of the protein synthesis from the inhibited level by Ca2+-deprivation. ATP and creatine phosphate contents in SCG were elevated by the presence of GM1 or α-SC, whereas [3H]AIB uptake and Na+, K+-ATPase activity were inhibited, suggesting that utilization for membrane transport was diminished as a result of GM1- or α-SC-induced decrease of ATPase activity. 相似文献
132.
Jun Hatazawa Hiroshi Itoh Eku Shimosegawa Iwao Kanno Matsutaroh Murakami Shuichi Miura Hidehiro Iida Toshio Okudera Atsushi Inugami Toshihide Ogawa Hideaki Fujita Yuichi Satoh Ken Nagata Yutaka Hirata Kazuo Uemura 《Annals of nuclear medicine》1994,8(3):213-217
We studied the brain uptake of amino acid in a patient with acute cerebral infarction with L-[2-(F-18)] fluorophenylalanine and positron emission tomography. The increased accumulation of the ligand was specifically found in the peri-infarct area where oxygen metabolism was still maintained but decreased later in the 72-day follow-up period. The kinetic analysis revealed that increased accumulation was not due to increased transport from the blood to the brain but to delayed washout from the brain to the blood. Although the mechanism is still unknown, abnormally high accumulation of L-[F-18]fluorophenylalanine may predict delayed neuronal changes after ischemic insults of the brain. 相似文献
133.
Tomita M Ayabe H Tagawa Y Hara S Tsuji H Oka T Akamine S Takahashi T Shingu H 《Breast cancer (Tokyo, Japan)》1995,2(2):113-117
The procedure of aspiration biopsy cytology by fine needle aspiration (ABC) is as option in establishing definitive diagnoses for breast cancers. In this series, a needle size of 21G was considered most suitable for ABC as well as flow cytometric DNA analysis. Histograms from fresh samples aspirated by fine needle clearly delineated a sharp peak in G&sup0;G(1) phases and also a better CV was obtained than with paraffin-embedded preparations. In addition, fresh samples gave more reliable DI and suggested the value of measuring nuclear DNA contents. It is believed that the prognoses of breast cancers are closely associated with DNA ploidy patterns. In this sense, flow cytometric DNA analysis of fresh samples of ABC is regarded as important in clinical use. 相似文献
134.
PCNA immunostaining combined with AgNOR staining in esophageal squamous cell carcinoma to identify patients with a poor prognosis 总被引:6,自引:0,他引:6
Yoshihisa Morisaki Shingo Shima Yutaka Yoshizumi Yoshiaki Sugiura Susumu Tanaka Seiichi Tamai 《Surgery today》1995,25(5):389-395
Immunostaining of the proliferating cell nuclear antigen (PCNA) provides important information about cell kinetics and is easily performed on routinely obtained formalin-fixed, paraffin-embedded materials. We report herein the results of a retrospective study on PCNA staining in esophageal cancer undertaken to determine its significance. As this study indicated that immunoreactivity was preserved in specimens fixed within 24 h, only 31 specimens from surgical patients were available for this investigation. The mean PCNA index of the patients without invasion to the adventitia (35.7±17.9) was significantly lower than that of those with invasion to the adventitia or neighboring structures (49.7±14.5), while the PCNA index did not correlate with other clinicopathologic parameters such as histologic type, lymph node metastases, or prognosis. However, when an analysis of PCNA staining was combined with an analysis of argyrophilic nucleolar organizer region (AgNOR) staining, a correlation with prognosis was found. In fact, seven patients with a high PCNA index (44) and AgNOR count (6) had a significantly poorer prognosis than the remaining 22 (P=0.0014), and six of these seven patients died within 2 years. These results indicate that this combined evaluation may be useful for the identification of patients with a poor prognosis among those undergoing surgery for esophageal squamous cell carcinoma. 相似文献
135.
Lin Y Kawamura T Anno T Ichihara Y Ohta T Saito M Fujioka Y Kimura M Okada T Kuwayama Y Wakai K Ohno Y 《Environmental health and preventive medicine》1999,4(3):117-121
It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk
factors in relation to severity and physical fitness is still controversial.
Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise
program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods.
Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program,
their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05)
without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic
blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05).
Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum
oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes
in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify
women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness. 相似文献
136.
Impaired glucose tolerance, diabetes mellitus, and gallstone disease: An extended study of male self-defense officials in Japan 总被引:2,自引:0,他引:2
Shizuka Sasazuki Suminori Kono Isao Todoroki Satoshi Honjo Yutaka Sakurai Kazuo Wakabayashi Masato Nishiwaki Hiroaki Hamada Hiroshi Nishikawa Hiroko Koga Shinsaku Ogawa Katsuya Nakagawa 《European journal of epidemiology》1999,15(3):245-251
Few studies have investigated the relation between glucose tolerance status and ultrasonographically determined gallstone disease. Using a 75-g oral glucose tolerance test, we examined the association of impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) with gallstone disease in Japanese men. Subjects were men aged 48 to 59 of the Japan Self-Defense Forces who received a preretirement health examination between October 1986 to December 1994. After exclusion of 12 men under insulin treatment in the consecutive series of 7637 men, 174 were found to have gallstones; 103 were at the state of postcholecystectomy, and 6899 had normal gallbladder. IGT and NIDDM were associated with a modestly increased risk of gallstone disease; adjusted odds ratios were 1.3 (95% confidence interval [CI]: 0.9–1.8) for IGT and 1.3 (95% CI: 0.8–2.0) for NIDDM after adjustment for hospital, rank, smoking, alcohol use, and body mass index. Adjusted odds ratio for IGT and NIDDM combined was 1.3 (95% CI: 1.0–1.7, p=0.08). When prevalent gallstones and postcholecystectomy were considered separately, NIDDM showed a significant, positive association with postcholecystectomy, but not with prevalent gallstones. The findings add to evidence that glucose intolerance is associated with a modest increase in the risk of gallstone disease. 相似文献
137.
Shohei Nakamura Yutaka Kobayashi Kazuhiko Tozuka Akihiko Tokue Akira Kimura Chikuma Hamada 《The Journal of urology》1996,156(4):1275-1279
Purpose
Circadian changes in urinary frequency, diuresis and bladder capacity were evaluated in middle-aged and elderly patients.Materials and Methods
A total of 2,703 urinations from 50 men (median age 66 years) was recorded with a 24-hour uroflowmetry system.Results
During a 24-hour period the elderly group showed increased frequency and decreased bladder capacity. No difference was observed in diuresis between the 2 age groups. From midnight to 6 a.m. frequency in the elderly group was significantly greater (p less than 0.01) than that in the middle-aged group.Conclusions
Increased frequency in the elderly group during these hours was primarily due to an increase in diuresis. 相似文献138.
Fujio Atsuta Kenichi Sato Koscak Maruyama Yutaka Shimada 《Journal of muscle research and cell motility》1993,14(5):511-517
Summary The distribution of connectin (titin), nebulin and -actinin in the areas of myotendinous junctions of chicken pectoralis muscles was examined by immunocytochemical methods. Staining with antibodies against connectin (4C9, SM1 and P1200) and nebulin formed doublets flanking nonterminal Z-bands; near the end of muscle fibres singlets were seen within the terminal sarcomere on the side adjacent to the terminal Z-bands. The apical regions of muscle processes, where no myosin filaments are present although actin filaments exist, were reactive with anti-nebulin but not with anti-connection. Antibodies against pectoralis (skeletal muscle type) -actinin stained non terminal Z-bands and that against gizzard (smooth muscle type) the sarcolemma. Terminal Z-bands were unreactive with both of these antibodies. These findings indicate that, although terminal and nonterminal Z-bands differ in their molecular composition, connectin and nebulin filaments appear to link myosin and actin filaments, respectively, to both Z-band types. 相似文献
139.
Kawanishi Toru Takahashi Atsushi Ohno Yasuo Takanaka Akira Kasuya Yutaka Omori Yoshihito 《Archives of toxicology》1983,54(4):323-330
A simple method for the quantitative estimation of the formation of N-nitrosodimethylamine (NDMA) in mice has been developed. Mice were frozen in liquid nitrogen and homogenized. NDMA was then extracted and analyzed by a gas chromatograph equipped with a thermal energy analyzer. In normal mice NDMA (100 nmole) administered orally was rapidly metabolized and recovery of NDMA was about 10% after 60 min. However, when pyrazole (300 mg/kg) was injected i.p. to mice 60 min before the administration of NDMA, more than 80% of the administered NDMA could be recovered within 60 min. This result suggested that in pyrazole pretreated mice the accurate amount of NDMA formed could be estimated. Therefore the NDMA formation was measured in the pyrazole pretreated mice. When 0.25 mole of aminopyrine and from 0.25 to 2.0 umole of sodium nitrite were simultaneously administered orally, the amount of the NDMA formation in 20 min was found to be from 8.2 to 60.3 nmole. These values are equal to about from 30 to 200 g/kg of body weight which are nearly daily doses expected to cause the carcinogenic effect on mice or rats. This method of measuring NDMA in pyrazole pretreated mice appears to be useful for investigating the in vivo formation of NDMA quantitatively. 相似文献
140.
Shin-ichi Hirano Naoki Agata Yutaka Hara Hiroshi Iguchi Masataka Shirai Hiroshi Tone Norimoto Urakawa 《Cancer chemotherapy and pharmacology》1991,28(4):266-272
Summary In the present study we examined the effects of pirarubicin [(2R)-4-0-tetrahydropyranyladriamycin, THP] on a cardiovascular system. An injection of THP (0.39–3.13 mg/kg, i. v.) reduced the mean blood pressure and caused an increase in the respiratory air rate in anesthetized rats. At 1.5×10–6–1.5×10–5
m, THP markedly relaxed a contraction induced by 10–7
m norepinephrine in rat aorta with endothelium but not in that without endothelium. At a dose of 0.02–0.5 mg, THP produced an increase in the contractile force and the perfusion flow of isolated perfused guinea pig hearts. At a higher concentration (4.5×10–5–1.5×10–4
m), it produced a slight increase in the contractile force of the left atria in guinea pigs. This positive inotropic action of THP was inhibited by diphenhydramine (10–6–5×10–5
m), chlorpheniramine (3×10–7–3×10–5
m), and tripelennamine (3×10–7–3×10–5
m) but not by propranolol (10–6
m), cimetidine (10–5
m), diltiazem (10–6
m), or ryanodine (10–8
m). THP given i. v. at 2.5 mg/kg elevated the plasma histamine level in anesthetized dogs. From these data, we conclude that THP mainly relaxed the rat aorta in the presence of endothelium and that at higher concentrations, it increased the contractile force in the cardiac muscle, probably mediated through the release of histamine. 相似文献