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21.
Differentiation of subtypes B and E of human immunodeficiency virus type 1 by polymerase chain reaction using novel env gene primers 总被引:2,自引:0,他引:2
Yagyu F Ikeda Y Ariyoshi K Sugiura W Wongkhomthong SA Masuda M Ushijima H 《Journal of virological methods》2002,101(1-2):11-20
Novel sets of env gene PCR primers for distinguishing human immunodeficiency virus type 1 (HIV-1) subtypes B and E were designed. These primers anneal to different regions of the env gene and amplify DNA fragments of distinct sizes in a subtype-specific manner. Blood samples from 11 HIV-1 carriers in Thailand and 46 carriers in Japan were examined by PCR. The new env primers detected HIV-1 proviral DNA in 100% (11/11) and 88% (37/42) of the subtype B and E infection cases, respectively. The env primers also detected proviral DNA in saliva and breast milk samples in seven of 11 cases and two of three cases, respectively. The PCR subtyping results matched completely with those obtained by nucleotide sequencing of the env V3 region. The results suggest that the PCR using the env primers designed in this study may be an accurate and cost-effective method for differentiating subtypes B and E of HIV-1 in a large number of clinical samples. However, subtype E specific primer cross-react with subtype A, C, G, the new primer in this study is useful for regions in South East Asia where subtype E is predominant. 相似文献
22.
The plasminogen activation system reduces fibrosis in the lung by a hepatocyte growth factor-dependent mechanism 总被引:12,自引:0,他引:12 下载免费PDF全文
Hattori N Mizuno S Yoshida Y Chin K Mishima M Sisson TH Simon RH Nakamura T Miyake M 《The American journal of pathology》2004,164(3):1091-1098
Mice deficient in the plasminogen activator inhibitor-1 gene (PAI-1-/- mice) are relatively protected from developing pulmonary fibrosis from bleomycin administration. We hypothesized that one of the protective mechanisms may be the ability of the plasminogen system to enhance hepatocyte growth factor (HGF) effects, which have been reported to be anti-fibrotic in the lung. HGF is known to be sequestered in tissues by binding to extracellular matrix components. Following bleomycin administration, we found that HGF protein levels were higher in bronchoalveolar lavage fluid from PAI-1-/- mice compared to wild-type (PAI-1+/+) mice. This increase could be suppressed by administering tranexamic acid, which inhibits plasmin activity. Conversely, intratracheal instillation of urokinase into bleomycin-injured PAI-1+/+ mice to activate plasminogen caused a significant increase in HGF within bronchoalveolar lavage and caused less collagen accumulation in the lungs. Administration of an anti-HGF neutralizing antibody markedly increased collagen accumulation in the lungs of bleomycin-injured PAI-1-/- mice. These results support the hypothesis that increasing the availability of HGF, possibly by enhancing its release from extracellular matrix by a plasmin-dependent mechanism, is an important means by which activation of the plasminogen system can limit pulmonary fibrosis. 相似文献
23.
Fumie Takewaki Hanako Nakajima Daiki Takewaki Yoshitaka Hashimoto Saori Majima Hiroshi Okada Takafumi Senmaru Emi Ushigome Masahide Hamaguchi Masahiro Yamazaki Yoshiki Tanaka Shunji Nakajima Hiroshi Ohno Michiaki Fukui 《Nutrients》2021,13(6)
The aim of this research was to reveal the characteristics of gut microbiome altered by acarbose intervention in Japanese patients with type 2 diabetes (T2D) and its possible association with habitual dietary intake. Eighteen patients with T2D were administered acarbose for four weeks. The abundances of two major phyla, namely Actinobacteria and Bacteroidetes, were reciprocally changed accompanied by the acarbose intervention. There were also significant changes in the abundances of ten genera, including the greater abundance of Bifidobacterium, Eubacterium, and Lactobacillus and the lower abundance of Bacteroides in the group after the intervention than that before the intervention. Hierarchical clustering of habitual dietary intake was performed based on the pattern of changes in the gut microbiota and were classified into distinct three clusters. Cluster I consisted of sucrose, cluster II mainly included fat intake, and cluster III mainly included carbohydrate intake. Moreover, the amount of change in Faecalibacterium was positively correlated with the intake of rice, but negatively correlated with the intake of bread. The intake of potato was negatively correlated with the amount of change in Akkermansia and Subdoligranulum. Acarbose altered the composition of gut microbiome in Japanese patients with T2D, which might be linked to the habitual dietary intake. 相似文献
24.
Junko Adachi Takeaki Naito Yasuhiro Ueno Yumi Ogawa Ichiya Ninomiya Yoshitsugu Tatsuno 《Archives of toxicology》1993,67(4):284-289
Peak E substance, 1,1-ethylidenebis[tryptophan], a contaminant found inl-tryptophan tablets, has been suggested as a causative agent for eosinophilia-myalgia syndrome (EMS). Peak E substance (50 mg/kg) was administered perorally to Wistar rats to determine its metabolism and distribution. A purification procedure using Bond Elut C8 cartridges followed by HPLC was developed for the determination of peak E substance. The plasma concentration of peak E substance was 136 ng/ml at 1 h, and urinary excretion was 717 ng at 5 h and 10342 ng for 5–24 h, showing slow excretion of peak E substance into urine. The amount of peak E substance in the contents of the large intestine at 5 h, however, was 3136 g, much greater than urinary excretion for 24 h, indicating considerable transfer of peak E substance to large intestine without decomposition by gastric fluid in the stomach. We have detected for the first time not only the occurrence of peak E substance in plasma and urine, but also 1-methyl-tetrahydro--carboline-3-carboxylic acid (MTCA) in blood and organs of rats treated with peak E substance, thereby suggesting MTCA as one of the the metabolites of peak E substance. The amount of MTCA in the contents of the large intestine as well as in urine of rats treated with peak E substance was significantly greater than inl-tryptophantreated rats (50 mg/kg p.o.), demonstrating that MTCA was more readily produced from peak E substance than froml-tryptophan. Finally, we propose acetaldehydeinduced production of MTCA from peak E substance. 相似文献
25.
1-Methyl-tetrahydro--carboline-3-carboxylic acid (MTCA) may cause eosinophilia-myalgia syndrome (EMS) associated with ingestion ofl-tryptophan. The distribution and excretion of MTCA were studied in rats which had received perorally a single 1.6 mg/kg dose of MTCA. MTCA concentrations in blood, kidney, liver, brain, heart, spleen, lung and gastrocnemius muscle were measured by HPLC combined with fluorometric detection. The concentration of MTCA in each organ reached a maximum at 1 h and then gradually declined. However, a significant level of MTCA still remained at 5 h, when 52% of ingested MTCA remained in the contents of the large intestine. Twenty-nine percent of the ingested MTCA was excreted in urine over the course of 24 h. A higher dose (10 mg/kg) of MTCA resulted in significant elevations in the concentrations and amounts of MTCA in the various organs. In addition, chronic treatment with a 10 mg/kg dose of MTCA for 6 weeks further increased the concentrations and amounts of MTCA in each organ. However, no histological changes were observed in any of the organs after chronic treatment. This is the first report which demonstrates accumulation of MTCA in the blood and various organs, including muscle, of rats. 相似文献
26.
A. Hirose R. Tsuji H. Shimizu T. Tatsuno H. Tanaka Y. Kumasaka M. Nakamura 《Naunyn-Schmiedeberg's archives of pharmacology》1990,341(1-2):8-13
Summary Electrophysiological studies using spectral analysis techniques were undertaken in rabbits to determine whether or not hippocampal rhythmical slow activity (RSA, theta wave activity) was affected by the 5-hydroxytryptamine1A (5-HT1A) agonists 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) and 3 , 4 , 7 , 7 -hexahydro-2-(4-(4-(2-pyrimidinyl)-1-piperazinyl)-butyl)-4, 7-methano-IH-isoindole-1,3(2H)-dione dihydrogen citrate (SM-3997, a newly synthesized anxiolytic drug). Intravenous administration of 8-OH-DPAT and SM-3997 induced a desynchronized pattern with low-amplitude slow wave activity in the hippocampal EEG and inhibited RSA generation following stimulation of the midbrain reticular formation. RSA was also inhibited by 5-HT1A related anxiolytics such as buspirone, gepirone, and ipsapirone. The effects of 8-OH-DPAT and SM-3997 on the hippocampal RSA were blocked by pindolol, which has 5-HT1A antagonistic activity. Direct microinjection of these 5-HTIA selective agonists into the hippocampus inhibited generation of the hippocampal RSA. These findings indicated that 8-OH-DPAT and SM-3997 inhibited the hippocampal RSA by acting on hippocampal 5-HTIA receptors.
Send offprint requests to A. Hirose at the above address 相似文献
27.
We used our new flow cytometric method to measure benzo[a]pyrene-diolepoxide-deoxyribonucleic acid adduct levels in peripheral lymphocytes from healthy male smokers and nonsmokers. Smokers who had pack-years of 20 or more had significantly higher mean benzo[a]pyrene-diol-epoxide-deoxyribonucleic acid adduct levels than nonsmokers. In smokers, the adduct levels were correlated significantly with age, years of smoking, and pack-years, whereas daily tobacco consumption was not correlated with adduct levels. We also found a positive relationship between age and benzo[a]pyrene-diol-epoxide-deoxyribonucleic acid adduct levels in nonsmokers. Passive exposure to tobacco smoke was not associated with adduct levels. The results of our study indicate that benzo[a]pyrene-diol-epoxide-deoxyribonucleic acid adduct levels may be closely related to aging and that tobacco smoking-as well as other environmental factors-may play a role in the benzo[a]pyrene-diol-epoxide-deoxyribonucleic acid adduct formation. 相似文献
28.
29.
Yoshihide Kii Katsuyoshi Nakatsuji Isamu Nose Masafumi Yabuuchi Michiaki Matsuda Tsugutaka Ito 《Drug development research》2003,58(2):209-217
The purpose of this study was to evaluate the effects of ebastine and terfenadine on the electrocardiogram of conscious dogs and cats. In dogs, terfenadine at oral doses of 30 mg/kg twice a day for 7 days prolonged the electrocardiographic QT interval and the corrected QT (QTc) interval on the seventh day, whereas the drug did not affect these parameters on the first day. Plasma concentrations of terfenadine and its active metabolite, fexofenadine, reached 306 and 8,541 ng/mL, respectively, on the seventh day. Ebastine at oral doses of 30 and 100 mg/kg once a day for 7 days was without effect on the QT and QTc intervals, whereas the drug slightly shortened the RR interval. On the seventh day following the dose of 100 mg/kg, plasma concentrations of ebastine and its active metabolite, carebastine, reached 36 and 1,939 ng/mL, respectively. In conscious cats, terfenadine at oral doses of 30 mg/kg twice a day for 7 days prolonged the QT and QTc intervals, QRS duration, JT and the corrected JT intervals. Unexpectedly, terfenadine induced ventricular tachyarrhythmia and premature beats. On the other hand, ebastine at oral doses of 100 mg/kg once a day for 7 days was without effect on the electrocardiographic parameters in cats. These results suggest that the electrocardiographic changes indicative of the proarrhythmic potential of terfenadine can be evaluated in conscious dogs and especially in conscious cats by repeated oral administration, and that ebastine does not induce such changes. 58:209–217, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
30.
Toru Sugiyama Takashi Nishida Akio Kataoka Kan Komai Naofumi Ookura Toshio Oobuchi Michiaki Yakushiji 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(2):92-96
Background We investigated retrospectively the records and tissue samples of patients with primary ovarian transitional cell carcinoma
to determine clinical and pathologic features.
Methods The records of 3 patients with ovarian transitional cell carcinoma were reviewed using data from several imaging techniques:
transvaginal ultrasound, computed tomography, and magnetic resonance imaging. We also determined levels of several tumor marker
molecules; and the level of carbohydrate antigen 125 (CA 125), was examined by means of immunohistochemistry.
Results The tumors of 2 patients were classified as pure trnasitional cell carcinoma; in the remaining patient, as predominantly transitional
cell carcinoma. All tumors were bilateral, and 2 of the 3 tumors formed solid masses. Areas of irregular high intensity signals
were seen in magnetic resonance images of the solid parts of the tumors. All 3 tumors tested positive for CA 125; histochemical
expression was confined to the tumor cell membrane and/or the cytoplasm in all cases. The tumors of all 3 patients tested
negative for carcinoembryonic antigen (CEA), and second-look laparotomies did not reveal any residual neoplasms in any of
the patients. The patients have been in a disease-free state for 34, 42, and 14 months, respectively.
Conclusion Our results suggest that transitional cell carcinomas tend to arise bilaterally and to form solid tumors. Magnetic resonance
imaging was a useful diagnostic modality in these cases. Transitional cell carcinoma was characterized by the presence of
CA 125 and the absence of CEA. 相似文献