26 results on '"Irokawa M"'
Search Results
2. Endothelial-derived nitric oxide preserves anticoagulant heparan sulfate expression in cultured porcine aortic endothelial cells
- Author
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Irokawa, M., Nishinaga, M., Ikeda, U., Shinoda, Y., Suematsu, M., Gouda, N., Ishimura, Y., and Shimada, K.
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- 1997
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3. Recent decline in hepatitis E virus prevalence among wild boars in Japan: Probably due to countermeasures implemented in response to outbreaks of classical swine fever virus infection.
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Takahashi M, Nishizawa T, Nishizono A, Kawakami M, Sato Y, Kawakami K, Irokawa M, Tamaru T, Miyazaki S, Shimada M, Ozaki H, Primadharsini PP, Nagashima S, Murata K, and Okamoto H
- Subjects
- Animals, Japan epidemiology, Swine, Prevalence, Classical Swine Fever Virus genetics, Classical Swine Fever Virus immunology, Classical Swine Fever Virus classification, Phylogeny, Immunoglobulin G blood, Hepatitis Antibodies blood, Genetic Variation, Hepatitis E virus genetics, Hepatitis E virus immunology, Hepatitis E virus classification, Hepatitis E virus isolation & purification, Hepatitis E epidemiology, Hepatitis E veterinary, Hepatitis E virology, Hepatitis E prevention & control, Sus scrofa virology, Classical Swine Fever epidemiology, Classical Swine Fever prevention & control, Classical Swine Fever virology, Disease Outbreaks veterinary, Genotype, RNA, Viral genetics
- Abstract
Previous studies have emphasized the necessity of surveillance and control measures for hepatitis E virus (HEV) infection in wild boars, an important reservoir of HEV. To assess the current situation of HEV infection in wild boars in Japan, this study investigated the prevalence and genetic diversity of HEV among wild boars captured in 16 prefectures of Japan during 2018-2023. Serum samples from 968 wild boars were examined for anti-HEV IgG antibodies and HEV RNA. The prevalence of anti-HEV IgG varied geographically from 0 % to 35.0 %. HEV RNA was detected in 3.6 % of boars, with prevalence varying by prefecture from 0 % to 22.2 %. Genotype 3 was the most prevalent genotype (91.9 %), followed by genotype 4 (5.4 %), with one strain closely related to genotype 6. The prevalence of HEV infection among wild boars decreased from 2018/2019 to 2022/2023 with significant declines in levels of anti-HEV IgG antibodies (14.5 % vs. 6.2 %, P < 0.0001) and HEV RNA (7.6 % vs. 1.5 %, P < 0.0001). Regional analysis showed varying trends, with no HEV RNA-positive boars found in several regions in recent years. A plausible factor contributing to the decline in HEV infection is the application of countermeasures, including installing fences to prevent intrusion into pig farms, implemented in response to the emergence of classical swine fever virus (CSFV) infection in wild boars and domestic pigs, with incidents reported annually since 2018. Further investigation is warranted to explore the association between countermeasures to CSFV infection and the decrease in HEV infection among wild boars., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2024
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4. Risk Factors for Prolonged Hospital Stay after Endoscopy.
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Nishizawa T, Yoshida S, Toyoshima O, Matsuno T, Irokawa M, Arano T, Ebinuma H, Suzuki H, Kanai T, and Koike K
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Background/aims: The recovery room used after endoscopy has limited capacity, and an efficient flow of the endoscopy unit is desired. We investigated the duration of hospital stay after endoscopy and the risk factors for prolonged hospital stay among outpatients., Methods: We retrospectively studied consecutive patients who underwent esophagogastroduodenoscopy or colonoscopy at the Toyoshima Endoscopy Clinic. We collected data on age, sex, body weight, midazolam and pethidine dosage, respiratory depression during endoscopy, and duration of hospital stay after endoscopy (scope out to check out). Risk factors for prolonged hospital stay (>100 minutes) were identified using multiple logistic regression analysis., Results: We enrolled 3,898 patients, including 3,517 (90.2%) patients tested under sedation and 381 (9.8%) patients tested without sedation. Overall, 442 (11.3%) patients had prolonged stay (>100 min). The mean time difference between sedation group and non-sedation group was 44.2 minutes for esophagogastroduodenoscopy and 39.1 minutes for colonoscopy. Age (odds ratio [OR], 1.025; 95% confidence interval [CI], 1.014-1.036), female sex (OR, 1.657; 95% CI, 1.220-2.249), and midazolam dose (OR, 1.019; 95% CI, 1.013-1.026) were independently associated with prolonged hospital stay after esophagogastroduodenoscopy, with similar results for colonoscopy., Conclusion: Old age, female sex, and midazolam dose were independent risk factors for prolonged hospital stay after endoscopy.
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- 2021
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5. Prevalence and genotype/subtype distribution of hepatitis E virus (HEV) among wild boars in Japan: Identification of a genotype 5 HEV strain.
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Takahashi M, Nishizawa T, Sato Y, Miyazaki S, Aikawa T, Ashida K, Tamaru T, Oguro K, Hayakawa F, Matsuoka H, Ozaki H, Kodera Y, Irokawa M, Hirose H, Nagashima S, Kawakami M, Mizuo H, Okamoto H, and Murata K
- Subjects
- Animals, Disease Reservoirs virology, Female, Hepatitis Antibodies blood, Hepatitis E transmission, Hepatitis E virus isolation & purification, Humans, Japan epidemiology, Male, Phylogeny, Prevalence, Swine, Disease Reservoirs veterinary, Genotype, Hepatitis E epidemiology, Hepatitis E veterinary, Hepatitis E virus classification, Hepatitis E virus genetics, Sus scrofa virology
- Abstract
To further investigate the prevalence of hepatitis E virus (HEV) infection and characterize HEV genomes among Japanese wild boars (Sus scrofa leucomystax), 1880 boars captured in 17 prefectures in Japan from 2013 to 2019 were studied. Overall, anti-HEV IgG was detected in 8.9 % and HEV RNA was detected in 3.9 % of boars, which was comparable with our previous studies during 2003-2013 (10.3 % and 3.5 %, respectively). Among 74 boar HEV strains obtained from infected boars in the present study, 50 (68 %) were classified into genotype 3 (3a and 3b), 23 (31 %) were classified into genotype 4 (4i), and the remaining strain (wbJGF_19-1) was classified into genotype 5. The wbGF_19-1 strain shared 92.7 % identity over the entire genome with the prototype genotype 5 strain (JBOAR135-Shiz09). The identification of the second genotype 5 HEV strain in a place that is located only 100 km from the site at which JBOAR135-Shiz09 was identified, suggests that genotype 5 HEV circulates within a relatively close range in Japan. Genetically similar HEV strains forming a clade were identified from wild boars living in each area during the observation period of 11-13 years, although the nucleotide sequence changed gradually, accounting for up to 3.4-3.6 % within the 412-nucleotide ORF2 sequence. Eight groups of boars with a cluster of HEV infections were observed, consisting of two, three or four infected offspring, presumably born to the same mother or offspring with their mother. These results suggest that wild boars continue to be important reservoirs for HEV infection in humans in Japan., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
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6. Kyoto classification in patients who developed multiple gastric carcinomas after Helicobacter pylori eradication.
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Sakitani K, Nishizawa T, Toyoshima A, Yoshida S, Matsuno T, Yamada T, Irokawa M, Takahashi Y, Nakai Y, Toyoshima O, and Koike K
- Abstract
Background: Endoscopic Kyoto classification predicts gastric cancer risk; however, the score in the patients with primary gastric cancer after Helicobacter pylori ( H. pylori ) eradication therapy is unknown., Aim: To elucidate the Kyoto classification score in patients with both single gastric cancer and multiple gastric cancers developed after H. pylori eradication., Methods: The endoscopist recorded the Kyoto classification at the endoscope and the Kyoto classification score at the time of the first diagnosis of gastric cancer after H. pylori eradication. The score was compared between single gastric cancer group and multiple gastric cancers group., Results: The Kyoto score at the time of diagnosis of 45 cases of gastric cancer after H. pylori eradication was 4.0 points in average. The score was 3.8 points in the single gastric cancer group, and 5.1 points in the multiple gastric cancers group. The multiple group had a significantly higher score than the single group ( P = 0.016). In the multiple gastric cancers group, all the patients (7/7) had 5 or higher Kyoto score, while in single gastric cancer group, the proportion of patients with a score of 5 or higher was less than half, or 44.7% (17/38)., Conclusion: Patients diagnosed with gastric cancer after H. pylori eradication tended to have advanced gastritis. In particular, in cases of multiple gastric cancers developed after H. pylori eradication, the endoscopic Kyoto classification score tended to be 5 or higher in patients with an open type atrophic gastritis and the intestinal metaplasia extended to the corpus., (©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.)
- Published
- 2020
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7. Relationship between smoking and a new index of arterial stiffness, the cardio-ankle vascular index, in male workers: a cross-sectional study.
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Hata K, Nakagawa T, Mizuno M, Yanagi N, Kitamura H, Hayashi T, Irokawa M, and Ogami A
- Abstract
Background: Cigarette smoking is one of the major factors that increases arterial stiffness. The purpose of this study was to examine further the relationship between smoking status and arterial stiffness using a new index, the cardio-ankle vascular index (CAVI), in male Japanese workers., Methods: This cross-sectional study included 4,729 male Japanese workers undergoing annual health checkups. CAVI was measured at the time of the annual health checkup between April 2007 and March 2008. The subjects were divided into three groups, smokers (n = 1,913), former smokers (n = 1,481) and non-smokers (n = 1,348) according to their responses to a questionnaire. We compared the CAVI in the three groups after adjusting for age. Multiple regression analysis was used to examine the association between CAVI and the number of cigarettes smoked per day in order to examine whether there was a dose-response relationship between smoking and CAVI., Results: The mean CAVI for each group was 7.81 ± 0.02 for smokers, 7.70 ± 0.02 for former smokers and 7.64 ± 0.02 for non-smokers. A significant difference was observed between each group. According to the results of multiple regression analysis, the standardized β of the number of cigarettes smoked per day was 0.09 (p < 0.01). This confirmed a positive association with CAVI., Conclusions: Our study demonstrated that there is a significant association between the number of cigarettes smoked per day and arterial stiffness, as measured by CAVI.
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- 2012
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8. Uptake transporter organic anion transporting polypeptide 1B3 contributes to the growth of estrogen-dependent breast cancer.
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Maeda T, Irokawa M, Arakawa H, Kuraoka E, Nozawa T, Tateoka R, Itoh Y, Nakanishi T, and Tamai I
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- Animals, Biological Transport, Breast Neoplasms genetics, Cell Line, Tumor, Cell Proliferation, Female, Gene Expression Regulation, Neoplastic, Humans, Organic Anion Transporters, Sodium-Independent genetics, Solute Carrier Organic Anion Transporter Family Member 1B3, Xenopus laevis, Breast Neoplasms metabolism, Estrone analogs & derivatives, Estrone metabolism, Organic Anion Transporters, Sodium-Independent metabolism
- Abstract
Estrone-3-sulfate is one of the most abundant estrogen precursors in postmenopausal women. We previously showed that estrone-3-sulfate transporters are present in human breast cancer-derived MCF-7 cells (J. Pharmacol. Exp. Ther. 311 (2004) 1032-1037) and that inhibition of estrone-3-sulfate uptake resulted in the suppression of cell growth (Pharm. Res. 22 (2005) 1634-1641); therefore, estrone-3-sulfate transporter should be a novel target for therapy of hormone-dependent breast cancers. The purpose of the present study is to identify the transporter(s) responsible for the uptake of estrone-3-sulfate in breast cancer cells. We obtained two subclones of MCF-7 cells with different estrone-3-sulfate uptake activities and searched for differentially expressed transporter genes by means of DNA microarray analysis. Among several candidate transporters identified, OATP1B3 was further evaluated, since the uptake characteristics of estrone-3-sulfate by MCF-7 cells seemed consistent with the transport properties of OATP1B3. The contribution of OATP1B3 to estrone-3-sulfate uptake by MCF-7 cells was examined by the relative activity factor (RAF) method, and was calculated to amount to 6%. This result suggests that OATP1B3 is one of the transporters contributing to the supply of the estrogen precursor estrone-3-sulfate to estrogen-dependent breast cancer cells., (Copyright © 2010 Elsevier Ltd. All rights reserved.)
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- 2010
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9. Estimation method of finger tapping dynamics using simple magnetic detection system.
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Kandori A, Sano Y, Miyashita T, Okada Y, Irokawa M, Shima K, Tsuji T, Yokoe M, and Sakoda S
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- Adult, Computer Simulation, Equipment Design, Equipment Failure Analysis, Female, Humans, Male, Reproducibility of Results, Sensitivity and Specificity, Fingers physiology, Magnetics instrumentation, Models, Biological, Movement physiology, Physical Examination instrumentation, Transducers
- Abstract
We have developed the simple estimation method of a finger tapping dynamics model for investigating muscle resistance and stiffness during tapping movement in normal subjects. We measured finger tapping movements of 207 normal subjects using a magnetic finger tapping detection system. Each subject tapped two fingers in time with a metronome at 1, 2, 3, 4, and 5 Hz. The velocity and acceleration values for both the closing and opening tapping data were used to estimate a finger tapping dynamics model. Using the frequency response of the ratio of acceleration to velocity of the mechanical impedance parameters, we estimated the resistance (friction coefficient) and compliance (stiffness). We found two dynamics models for the maximum open position and tap position. In the maximum open position, the extensor muscle resistance was twice as high as the flexor muscle resistance and males had a higher spring constant. In the tap position, the flexor muscle resistance was much higher than the extensor muscle resistance. This indicates that the tapping dynamics in the maximum open position are controlled by the balance of extensor and flexor muscle friction resistances and the flexor stiffness, and the flexor friction resistance is the main component in the tap position. It can be concluded that our estimation method makes it possible to understand the tapping dynamics.
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- 2010
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10. Visceral fat area and markers of insulin resistance in relation to colorectal neoplasia.
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Yamamoto S, Nakagawa T, Matsushita Y, Kusano S, Hayashi T, Irokawa M, Aoki T, Korogi Y, and Mizoue T
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- Adult, Case-Control Studies, Female, Humans, Logistic Models, Male, Middle Aged, Obesity, Abdominal metabolism, Odds Ratio, Colorectal Neoplasms epidemiology, Colorectal Neoplasms etiology, Colorectal Neoplasms metabolism, Insulin Resistance physiology, Intra-Abdominal Fat metabolism, Obesity, Abdominal complications, Obesity, Abdominal epidemiology
- Abstract
Objective: Although abdominal obesity and related metabolic abnormalities are hypothesized to promote colorectal carcinogenesis, direct confirmation of this effect is required. Here, we examined the relation of early-stage colorectal neoplasia to visceral fat area and markers of insulin resistance., Research Design and Methods: Subjects were participants in a comprehensive health screening conducted at the Hitachi Health Care Center, Ibaraki, Japan. During a 3-year period (2004-2007), a total of 108 patients with early-stage colorectal neoplasia, including 22 with early cancer, were identified among individuals who received both colorectal cancer screening and abdominal computed tomography scanning. Three control subjects matched to each case subject were randomly selected from those whose screening results were negative. Conditional logistic regression analysis was used to examine the association of measures of obesity and markers of insulin resistance with colorectal neoplasia, with adjustment for smoking and alcohol drinking., Results: Visceral fat area, but not subcutaneous fat area, was significantly positively associated with colorectal cancer, with odds ratios (95% CI) for the lowest to highest tertile of visceral fat area of 1 (reference), 2.17 (0.45-10.46), and 5.92 (1.22-28.65), respectively (P(trend) = 0.02). Markers of insulin resistance, particularly fasting glucose, were also positively associated with colorectal cancer risk. In contrast, no associations were observed for colorectal adenomas., Conclusions: These results suggest that visceral adipose tissue accumulation and insulin resistance may promote the development of early-stage cancer but not adenoma in the colorectum.
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- 2010
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11. Detection of exaggerated blood pressure response using laboratory of physical science protocol and risk of future hypertension.
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Odahara T, Irokawa M, Karasawa H, and Matsuda S
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- Adult, Employment, Exercise Test, Follow-Up Studies, Humans, Male, Middle Aged, Predictive Value of Tests, Risk Factors, Survival Analysis, Travel, Blood Pressure physiology, Hypertension epidemiology
- Abstract
Objective: To assess the usefulness of the Laboratory of Physical Science (LOPS) protocol for detecting exaggerated blood pressure (BP) response as a risk factor for future hypertension when controlling for work and personal factors., Methods: Subjects were 815 healthy normotensive men (mean age, 43.1 ± 6.76 yr; range, 29-64 yr) who participated in the LOPS protocol, a graded 4-stage exercise test undertaken for the measurement of 40-70% of maximum oxygen consumption. A hypertensive response was defined as systolic blood pressure (SBP) of 250 mmHg or diastolic blood pressure (DBP) of 120 mmHg during the exercise test., Results: New-onset hypertension or the initiation of antihypertensive drug treatment had occurred in 108 men (13.3%) after 7 yr of follow-up. Cox proportional survival analysis revealed significantly increased risks of developing hypertension were associated with exaggerated BP response to exercise (hazard ratio, 2.3; 95% confidence interval, 1.4-3.7) and higher frequency of business trips (hazard ratio, 1.7; 95% confidence interval, 1.2-2.5) after multivariable adjustments for work and personal-related risk factors., Conclusions: These results suggest that the LOPS protocol is effective for detecting exaggerated BP response as a risk factor for future hypertension when controlling for work and personal-related risk factors. Exaggerated BP response to exercise and higher frequency of business trips are risk factors for developing future hypertension.
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- 2010
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12. Predominant contribution of rat organic anion transporting polypeptide-2 (Oatp2) to hepatic uptake of beta-lactam antibiotics.
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Nakakariya M, Shimada T, Irokawa M, Koibuchi H, Iwanaga T, Yabuuchi H, Maeda T, and Tamai I
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- 1-Methyl-4-phenylpyridinium pharmacology, Animals, Estrone analogs & derivatives, Estrone pharmacology, Female, Hepatocytes drug effects, Kinetics, Liver-Specific Organic Anion Transporter 1 metabolism, Male, Multidrug Resistance-Associated Proteins metabolism, Oocytes, Organic Anion Transporters antagonists & inhibitors, Organic Anion Transporters genetics, Organic Anion Transporters, Sodium-Independent metabolism, Rats, Rats, Wistar, Solute Carrier Organic Anion Transporter Family Member 1B3, Sulfobromophthalein pharmacology, Tetraethylammonium pharmacology, Xenopus laevis, Anti-Bacterial Agents metabolism, Hepatocytes metabolism, Nafcillin metabolism, Organic Anion Transporters metabolism, beta-Lactams metabolism
- Abstract
Purpose: To identify the rat hepatic basolateral transporters involved in the hepatic uptake of beta-lactam antibiotics using nafcillin as a model beta-lactam antibiotic that undergoes extensive biliary excretion., Materials and Methods: Uptake by isolated rat hepatocytes and Xenopus laevis oocytes expressing organic anion transporting peptides (Oatp1, 2, and 4) and organic anion transporter (OAT2) was evaluated., Results: Nafcillin uptake by isolated rat hepatocytes was saturable with the Km of 210 microM and was significantly inhibited by anionic compounds (estrone-3-sulfate and sulfobromophthalein), but not by cationic compounds (tetraethylammonium and 1-methyl-4-phenylpyridinium). In an in vitro uptake study by Xenopus oocytes expressing hepatic basolateral membrane transporters, nafcillin was transported by multiple Oatps with Km values of 4120 microM (Oatp1/Oatp1a1), 198 microM (Oatp2/Oatp1a4), and 1,570 microM (Oatp4/Oatp1b2), though it was not transported by hOAT2. Comparison of affinity and analysis by the relative activity factor method indicated that Oatp2 is the predominant contributor to the hepatic uptake of nafcillin. Cefadroxil, cefazolin, cefmetazole, cefoperazone, cefsulodin, and cephalexin, though not cefotaxime or ceftriaxone, were also substrates of Oatp2., Conclusion: These findings suggest that Oatp2 plays a key role in the hepatic uptake of nafcillin and most other beta-lactam antibiotics in rats.
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- 2008
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13. Identification and species similarity of OATP transporters responsible for hepatic uptake of beta-lactam antibiotics.
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Nakakariya M, Shimada T, Irokawa M, Maeda T, and Tamai I
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- Anilides pharmacology, Animals, Benzoates pharmacology, Cryopreservation, Hepatocytes metabolism, Humans, Kinetics, Liver-Specific Organic Anion Transporter 1, Oocytes metabolism, Organic Anion Transporters antagonists & inhibitors, Organic Anion Transporters, Sodium-Independent antagonists & inhibitors, Organic Anion Transporters, Sodium-Independent metabolism, Rats, Sincalide metabolism, Solute Carrier Organic Anion Transporter Family Member 1B3, Xenopus laevis, Liver metabolism, Nafcillin metabolism, Organic Anion Transporters metabolism, beta-Lactams metabolism
- Abstract
The present study was designed to identify the organic anion transporting polypeptide (OATP) molecule(s) responsible for the uptake of beta-lactam antibiotics in human liver, using cryopreserved hepatocytes, as well as Xenopus oocytes and cultured cells expressing human OATPs. Nafcillin uptake by human hepatocytes was saturable with a Km of 533 microM. In vitro uptake studies revealed that OATP1B3 and OATP1B1 transported nafcillin with Km values of 74 microM and 11 mM, respectively. Analysis by the relative activity factor method suggested that OATP1B3 contributes mainly to nafcillin uptake and OATP1B1 contributes moderately. This conclusion was supported by the results of a study with selective inhibitors. Furthermore, OATP1B3 transported six other beta-lactam antibiotics, and their uptake clearances by OATP1B3 correlated well with those mediated by rat Oatp1a4, which is the predominant contributor to basolateral uptake of nafcillin by rat hepatocytes. These findings suggest that OATP1B3 plays a major role in the hepatic uptake of beta-lactam antibiotics in humans, and probably corresponds functionally to Oatp1a4 in rat liver.
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- 2008
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14. Carnitine/organic cation transporter OCTN2-mediated transport of carnitine in primary-cultured epididymal epithelial cells.
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Kobayashi D, Irokawa M, Maeda T, Tsuji A, and Tamai I
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- Acetylcarnitine pharmacology, Amino Acid Transport Systems, Animals, Betaine analogs & derivatives, Betaine pharmacology, Biological Transport, Carnitine pharmacology, Cells, Cultured, Dose-Response Relationship, Drug, Leucine pharmacology, Lysine pharmacology, Male, Organic Cation Transport Proteins antagonists & inhibitors, Organic Cation Transport Proteins genetics, Pyrilamine pharmacology, Quinidine pharmacology, RNA analysis, Rats, Rats, Sprague-Dawley, Reverse Transcriptase Polymerase Chain Reaction, Sodium metabolism, Solute Carrier Family 22 Member 5, Time Factors, Carnitine metabolism, Epididymis metabolism, Epithelial Cells metabolism, Organic Cation Transport Proteins metabolism
- Abstract
Carnitine is essential for the acquisition of motility and maturation of spermatozoa in the epididymis, and is accumulated in epididymal fluid. In this study, carnitine transport into primary-cultured rat epididymal epithelial cells was characterized to clarify the nature of the transporter molecules involved. Uptake of carnitine by primary-cultured epididymal epithelial cells was time, Na(+) and concentration dependent. Kinetic analysis of carnitine uptake by the cells revealed the involvement of high- and low-affinity transport systems with Km values of 21 microM and 2.2 mM respectively. The uptake of carnitine by the cells was significantly reduced by inhibitors of carnitine/organic cation transporter (OCTN2), such as carnitine analogues and cationic compounds. In RT-PCR analysis, OCTN2 expression was detected. These results demonstrated that the high-affinity carnitine transporter OCTN2, which is localized at the basolateral membrane of epididymal epithelial cells, mediates carnitine supply into those cells from the systemic circulation as the first step of permeation from blood to spermatozoa.
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- 2005
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15. Suppression of cell proliferation by inhibition of estrone-3-sulfate transporter in estrogen-dependent breast cancer cells.
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Nozawa T, Suzuki M, Yabuuchi H, Irokawa M, Tsuji A, and Tamai I
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- Alkaline Phosphatase biosynthesis, Breast Neoplasms metabolism, Cell Line, Tumor, Dose-Response Relationship, Drug, Estrone antagonists & inhibitors, Estrone pharmacokinetics, Female, Humans, Indicators and Reagents pharmacology, Membrane Transport Proteins genetics, Membrane Transport Proteins metabolism, Sulfobromophthalein pharmacology, Transcriptional Activation, Breast Neoplasms drug therapy, Cell Proliferation drug effects, Estrogens pharmacology, Estrone analogs & derivatives, Membrane Transport Proteins drug effects
- Abstract
Purpose: The aim of the study is to suppress the progress of estrogen-dependent breast cancer by inhibiting the membrane transporter, which mediates the internalization of estrone-3-sulfate as estrogen precursor in the cancer cells., Methods: The uptake of estrone-3-sulfate by estrogen-dependent breast cancer MCF-7 cells was measured, and inhibitory study using various organic anions on estrone-3-sulfate uptake by MCF-7 cells was conducted. The effects of the inhibitor on the transcription of reporter gene and cell proliferation induced by estrone-3-sulfate were examined., Results: The uptake of estrone-3-sulfate by MCF-7 cells was saturable with Km value of 2.32 microM. The uptake was Na+-independent and was inhibited by several anionic compounds such as bromosulfophthalein. Bromosulfophthalein also significantly inhibited the transcription of reporter gene via estrogen response element and cell proliferation induced by estrone-3-sulfate. However, the transcriptional activation or cell proliferation induced by estrone was not inhibited by bromosulfophthalein. Reverse transcription-polymerase chain reaction analysis revealed the expression of mRNA of organic anion transporting polypeptide (OATP)-D and OATP-E as possible candidates to transport estrone-3-sulfate., Conclusions: The uptake of estrone-3-sulfate is mediated by Na+-independent transporter(s). Inhibitor of estrone-3-sulfate transporter suppressed the transcription and cell proliferation induced by estrone-3-sulfate in MCF-7 cells. The results provide the basis of a novel strategy for breast cancer treatment by focusing on the transporter responsible for the uptake of estrone-3-sulfate.
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- 2005
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16. Effect of a Change in the Sleep/Wake Cycle on the Diurnal Variation of Fibrinolytic Parameters.
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Irokawa M, Nishinaga M, Funayama H, Ikeda U, and Shimada K
- Abstract
The mechanism underlying the circadian rhythm of fibrinolysis is not well understood. To evaluate the influences of wakefulness and of the intrinsic circadian rhythm on fibrinolytic activity, we examined diurnal changes (8:00 am vs. 8:00 pm) in plasminogen activator inhibitor-1 (PAI-1) activity, tissue plasminogen activator (t-PA) antigen levels, and t-PA activity, as well as in plasma serum cortisol levels, in 10 healthy males (21 +/- 2 years) for two consecutive days. On the first day, subjects remained awake all day and night. They slept during the daytime (8:30 am to 5:30 pm) on the following day. PAI-1 activity and cortisol levels were significantly decreased, and t-PA activity tended to increase during the daytime on the first day. On the morning following overnight wakefulness, PAI-1 activity and cortisol levels did not return to the levels of the previous morning. On the second day, the afternoon decrease in PAI-1 activity, but not cortisol levels, was still observed, although its magnitude was substantially attenuated. No significant diurnal changes were observed in the levels of t-PA antigen throughout the study period. These findings suggest that the diurnal variation of fibrinolytic activity may be governed by an intrinsic circadian rhythm of PAI-1, which can be modified by a change in the time of wakefulness.
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- 1998
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17. Importance of aortic wave reflections in age-associated central blood pressure changes in nonhypertensive humans.
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Miyashita H, Ikeda U, Irokawa M, Yaginuma T, and Shimada K
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- Adolescent, Adult, Aged, Aged, 80 and over, Aorta diagnostic imaging, Blood Pressure, Humans, Middle Aged, Pulse, Transducers, Pressure, Ultrasonography, Aging physiology, Aorta physiology
- Published
- 1995
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18. Expression of monocyte chemoattractant protein-1 in vascular tissue.
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Seino Y, Ikeda U, Takahashi M, Hojo Y, Irokawa M, Kasahara T, and Shimada K
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- Animals, Arteriosclerosis etiology, Arteriosclerosis metabolism, Base Sequence, Calcium-Calmodulin-Dependent Protein Kinases metabolism, Cattle, Cells, Cultured, Humans, Molecular Sequence Data, Muscle, Smooth, Vascular cytology, Rats, Arteriosclerosis physiopathology, Chemokine CCL2 genetics, Muscle, Smooth, Vascular metabolism, RNA, Messenger biosynthesis
- Abstract
We investigated monocyte chemoattractant protein-1 (MCP-1) mRNA expression in rat vascular smooth muscle cells (VSMC) and in human atherosclerotic arteries to test the involvement of MCP-1 in the pathogenesis of atherosclerosis. In Northern blot analysis, MCP-1 mRNA expression was not observed in unstimulated cultured rat vascular smooth muscle cells (VSMC), but its expression was clearly observed by exposure to tumour necrosis factor-alpha (100 U/ml) for 2-6 h. Mitogen-activated protein kinase activity in VSMC incubated in serum-free culture medium was increased by exposure to 0.5% fetal bovine serum, while the effect was significantly suppressed in the presence of MCP-1 (100 ng/ml). We then evaluated MCP-1 mRNA expression in atherosclerotic arteries obtained from 12 patients undergoing bypass revascularization through reverse transcription-polymerase chain reaction analysis and observed MCP-1 mRNA expression in all atherosclerotic arteries studied. These results support the premise that MCP-1 is secreted by VSMC in atherosclerotic plaques as well as by endothelial cells and macrophages and contributes to the pathogenesis of atherosclerosis.
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- 1995
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19. Sjögren's syndrome with pleural effusion.
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Ogihara T, Nakatani A, Ito H, Irokawa M, Ban S, Takahashi A, Nishinarita M, and Oka Y
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- Biopsy, Humans, Male, Middle Aged, Pleural Effusion diagnosis, Sjogren's Syndrome diagnosis, Pleural Effusion etiology, Sjogren's Syndrome complications
- Abstract
Sjögren's syndrome (Sjs) can cause many organic changes, but is rarely accompanied by pleuritis. We report here a 62-year-old patient with subclinical Sjs who developed unilateral pleuritis with moderate effusion. He was diagnosed to have subclinical Sjs based on the positivity of anti SS-A/SS-B antibodies and the biopsy findings of minor salivary glands which revealed lymphocyte infiltration around the duct. In the pleural effusion, both increased lymphocytes and anti SS-A/SS-B antibodies were observed. He showed no signs of infection nor malignancy. There was no direct evidence that he had other collagen diseases which cause pleuritis. We conclude that the pleuritis was caused by Sjs. In patients with Sjs, activated polyclonal B lymphocytes and autoantibodies are considered to cause systemic tissue damage. This case indicates that these factors can cause pleuritis in Sjs patients.
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- 1995
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20. The coagulation system is activated in idiopathic cardiomyopathy.
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Yamamoto K, Ikeda U, Furuhashi K, Irokawa M, Nakayama T, and Shimada K
- Subjects
- Antithrombin III analysis, Atrial Function, Left physiology, Cardiomyopathy, Dilated diagnostic imaging, Cardiomyopathy, Hypertrophic diagnostic imaging, Case-Control Studies, Echocardiography, Enzyme-Linked Immunosorbent Assay, Female, Fibrin Fibrinogen Degradation Products analysis, Fibrinolysin analysis, Fibrinopeptide A analysis, Humans, Male, Middle Aged, Peptide Hydrolases analysis, Ventricular Dysfunction, Left blood, Ventricular Dysfunction, Left diagnostic imaging, alpha-2-Antiplasmin analysis, beta-Thromboglobulin analysis, Antifibrinolytic Agents, Blood Coagulation physiology, Blood Coagulation Factors analysis, Cardiomyopathy, Dilated blood, Cardiomyopathy, Hypertrophic blood
- Abstract
Objectives: We investigated the plasma levels of molecular markers for platelet activity and the thrombotic and fibrinolytic status in patients with hypertrophic cardiomyopathy and dilated cardiomyopathy to determine the activating site of coagulation in these disorders., Background: A thromboembolic event is a serious complication in patients with idiopathic cardiomyopathy. However, the activating site of the coagulation system in idiopathic cardiomyopathy has not been fully investigated., Methods: We determined the plasma levels of molecular markers for platelet activity (platelet factor 4 and beta-thromboglobulin), thrombotic status (fibrinopeptide A and thrombin-antithrombin III complex) and fibrinolytic status (D-dimer and plasmin-alpha 2-plasmin inhibitor complex) in 13 patients with hypertrophic cardiomyopathy, 17 patients with dilated cardiomyopathy and 20 normal subjects., Results: Plasma levels of platelet factor 4, beta-thromboglobulin and plasmin-alpha 2-plasmin inhibitor complex did not differ significantly among the three groups, whereas plasma levels of fibrinopeptide A and thrombin-antithrombin III complex in both patient groups were significantly higher than those in normal subjects. Plasma levels of D-dimer in patients with dilated cardiomyopathy were significantly higher than those in patients with hypertrophic cardiomyopathy and normal groups. In patients with hypertrophic cardiomyopathy, both fibrinopeptide A and thrombin-antithrombin III complex levels were significantly correlated with left atrial diameter. In patients with dilated cardiomyopathy, fibrinopeptide A and thrombin-antithrombin III complex levels showed a positive correlation with left ventricular end-diastolic volume and a negative correlation with fractional shortening of the left ventricle., Conclusions: The activated coagulation system in patients with hypertrophic and dilated cardiomyopathy may be triggered by left atrial dilation in hypertrophic cardiomyopathy and left ventricular enlargement and dysfunction in dilated cardiomyopathy.
- Published
- 1995
- Full Text
- View/download PDF
21. [Efficacy of combination therapy against MRSA in Ibaraki Prefecture].
- Author
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Otsuka M, Sawahata T, Nakai T, Hasegawa S, Iwata S, Yoshizawa Y, Ishida H, Irokawa M, Goto A, and Shinohara Y
- Subjects
- Adolescent, Adult, Aged, Anti-Bacterial Agents therapeutic use, Child, Child, Preschool, Dibekacin analogs & derivatives, Dibekacin therapeutic use, Female, Fosfomycin therapeutic use, Humans, Infant, Japan, Lactams, Male, Middle Aged, Pseudomonas Infections complications, Pseudomonas Infections drug therapy, Staphylococcal Infections complications, Staphylococcal Infections microbiology, Staphylococcus aureus isolation & purification, Aminoglycosides, Drug Therapy, Combination therapeutic use, Methicillin Resistance, Staphylococcal Infections drug therapy, Staphylococcus aureus drug effects
- Abstract
Clinical efficacies of fosfomycin (FOM) or arbekacin (ABK) plus beta-lactam combination therapies against methicillin-resistant Staphylococcus aureus (MRSA) infections were examined in 15 major hospitals in Ibaraki Prefecture. The subjects were 54 inpatients from January 1991 to April 1993, and most of them showed moderate to severe infections with underlying diseases. MRSA alone was isolated from 23 patients and the other 31 patients had polymicobes including MRSA. Pseudomonas aeruginosa was the most frequent among the co-isolated strains. The number of patients treated with FOM and cefmetazole (CMZ) was 22 (Group C) and that with FOM and flomoxef (FMOX) was 25 (Group F). CMZ or FMOX was administrated 60 minutes after FOM administration. To 8 nonresponding patients in Groups C and F and 7 nonresponders to the other therapies, ABK and ceftazidime (CAZ) or ABK and piperacillin (PIPC) were treated simultaneously (Group A). The clinical efficacies of Groups C and F were 63.6% and 64%, respectively. The bacteriological efficacies (eradication rates) of both groups including microbial substitutions were 42.9% in the former and 56.5% in the latter. No statistical differences were observed in the clinical and the bacteriological efficacies between Groups C and F. The clinical and bacteriological efficacies in Group A were 66.7% and 46.2%, respectively. No side effects were observed in any cases. Mild disturbances of hepatic functions were observed in 2 cases of Groups C and F, and there were no abnormal laboratory test results in Group A.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1994
22. [Survey of MRSA infection in Ibaraki-ken--Ibaraki Association for infectious diseases].
- Author
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Hasegawa S, Yoshizawa Y, Nakai T, Sawahata T, Ishida H, Irokawa M, Iwata S, Goto A, Shinohara Y, and Togawa S
- Subjects
- Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents therapeutic use, Drug Resistance, Microbial, Humans, Japan epidemiology, Prevalence, Staphylococcal Infections drug therapy, Staphylococcal Infections epidemiology, Staphylococcus aureus isolation & purification, Methicillin Resistance, Staphylococcal Infections microbiology, Staphylococcus aureus drug effects
- Abstract
This study which was undertaken at several major hospitals in Ibaraki-ken revealed that, 1) the proportion of Staphylococcus aureus in all the isolates ranged from 5% to 17% and the prevalence of MRSA in isolates of Staphylococcus aureus varied from 51% to 82% depending upon each individual hospital. 2) the clinical response to FOM and CMZ combination therapy was 88.9% and, to FOM and CZON was 57.1% showing no statistical differences between the two regimens. 3) in vitro analyses assessed by the FIC index of 251 isolates revealed that FOM had an additive or synergistic effect with CMZ in 53.8%, with CZON in 66.9%, with minocycline (MINO) in 43.8%, with cefamandole (CMD) in 61.8%, with cefazolin (CEZ) in 62.9% and with imipenem/cliastatin sodium (IPM/CS) in 68.9% at all isolates. 4) the cumulative curve of susceptibility to single CMZ and the combination of CMZ and FOM revealed that the blood levels of CMZ at 3 hours after intravenous administration covered 57% of isolates when used alone and 82% of isolates when in combination with FOM. The blood levels of CZON at 3 hours covered 5% of isolates when used alone and 41% when in combination with FOM. The extent of the therapeutic effect increased from 6% to 42% by CMD, from 12% to 54% by CEZ, from 20% to 58% by IPM/CS and from 78% to 84% by MINO. The combination of CMZ and FOM was found to be the most effective for enhanced effects on MRSA in vitro.
- Published
- 1992
23. [Effect of H1- and H2-receptor antagonists on late asthmatic responses].
- Author
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Nakazawa T, Irokawa M, Nagasawa T, Fueki R, and Kobayashi S
- Subjects
- Drug Therapy, Combination, Humans, Male, Middle Aged, Asthma drug therapy, Chlorpheniramine therapeutic use, Cimetidine therapeutic use, Guanidines therapeutic use
- Published
- 1983
24. [Indomethacin-induced asthma (author's transl)].
- Author
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Irokawa M, Nemoto T, Nakazawa T, Fueki R, and Kobayashi S
- Subjects
- Adult, Aspirin adverse effects, Female, Humans, Male, Middle Aged, Asthma chemically induced, Indomethacin adverse effects
- Published
- 1977
25. [A case of hypersensitivity pneumonitis relation to sericulture (sericulturist's lung disease)].
- Author
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Umegae Y, Matsui S, Irokawa M, Katakai S, Nakazawa T, Iizuka K, Miura S, Fueki R, Kobayashi S, and Kitaichi M
- Subjects
- Alveolitis, Extrinsic Allergic pathology, Bronchial Provocation Tests, Female, Humans, Lung pathology, Middle Aged, Occupational Diseases pathology, Alveolitis, Extrinsic Allergic diagnosis, Bombyx, Occupational Diseases diagnosis
- Published
- 1986
26. [Inhibitory effects of various drugs on histamine or allergen-induced bronchoconstriction].
- Author
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Nakazawa T, Umegae Y, Matsui S, Irokawa M, and Kobayashi S
- Subjects
- Adolescent, Adult, Aged, Animals, Diethylcarbamazine therapeutic use, Drug Evaluation, Female, Guinea Pigs, Histamine Antagonists therapeutic use, Humans, Indomethacin therapeutic use, Male, Middle Aged, Prednisolone therapeutic use, Asthma drug therapy
- Published
- 1985
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