Search PubMed⌕ Search

Biomedical subjects

E Tanaka

Publications and source records attributed to E Tanaka.

At least 181 records · Page 10Linked to original sources
PubMed1999

[The need for new antituberculosis agents in Japan].

We discussed the need of new antituberculosis agents in Japan concerning drug adverse reactions in particular as well as drug interactions and drug resistance. We reviewed medical charts of hospitalized patients receiving standard antituberculosis chemotherapy (INH + RFP + EB/SM +/- PZA), and analyzed all symptoms, signs and abnormal laboratory data presumably caused by the chemotherapy. About 48% of 228 cases analyzed had at least 1 episode of adverse reactions: 77 episodes of hepatotoxicity, 15 episodes of ototoxicity, 14 episodes of eruption, 14 episodes of ocular toxicity and so on. About 23% cases treated with RFP, 20% cases with SM, 12% cases with INH and 7.7% cases with EB had at least 1 episode of adverse reactions due to the corresponding agent. In 59 cases, at least one agent was stopped to administer because of adverse reactions. Finally, standard chemotherapy could not be completed in 23% of all cases, and in stead, the other agents, mainly new quinolones, were administered. RFP induces cytochrome P450 3A in the liver to decrease the activities of many drugs, such as cyclosporin A, tacrolimus, protease inhibitor, itraconazole, and clarithromycin. In some clinical settings, RFP cannot be administered in combination with such drugs. In conclusions, new antituberculosis agents that have strong activities with less adverse reactions and drug interactions are needed in Japan, even without considering drug resistance.

Aged↗
PubMed1999

[Hepatitis E].

Explore the source record for details and available documents.

Biomarkers↗
PubMed1999

Digitized cerebral synchrotron radiation angiography: quantitative evaluation of the canine circle of Willis and its large and small branches.

BACKGROUND AND PURPOSE: Conventional X-ray angiography lacks the sensitivity and spatial resolution needed to detect small amounts of iodinated contrast material and to quantitate diameters of the small vessels in the brain. The purpose of this study was to ascertain whether digitized synchrotron radiation microangiography, with the use of a high-definition TV camera system, can accurately show small cerebral vessels. METHODS: Six anesthetized dogs were exposed to monochromatic synchrotron radiation with an energy level of 33.3 keV optimized for iodine detection while iodinated contrast material was injected into the brachiocephalic and vertebral arteries. The images were detected with a high-definition TV camera system with a spatial resolution of 30 microm. In all, 26 cerebral angiograms of the circle of Willis with its branches were obtained, and the images were digitized at a workstation. RESULTS: The small branches of the circle of Willis were clearly visible on all images. Vasodilatation of the circle of Willis and its large and small branches induced by CO2 inhalation was quantitatively confirmed on the images: for example, the diameter of one small branch was increased from 0.24 +/- 0.04 mm to 0.38 +/- 0.12 mm. Temporal subtraction improved the image quality. CONCLUSION: The synchrotron radiation angiographic system is useful for visualizing large and small vessels deep in the brain as well as for quantitating their diameters.

Angiography, Digital Subtraction↗
PubMed1999

[Non A-G chronic hepatitis in Japan].

It is clear that certain patients with viral hepatitis are also seronegative for types A, B, C, D, and E. Although hepatitis G virus was discovered recently, this virus has been reported to be non-contributing or only slightly conductive to liver dysfunction. In this article, epidemiological studies regarding patients seronegative for types A to G chronic hepatitis in Japan are reported. Among 1089 patients with chronic liver disease, twenty-five patients (1.8%; 14 chronic hepatitis, 4 cirrhosis, 2 hepatocellular carcinoma) were diagnosed as non A-G hepatitis (negative for HbsAg, HCV-Ab, and HGV RNA). Only 3 of 25 these patients had histories of blood transfusion. The levels of transaminase in the patients with chronic non-A to G hepatitis (without hepatocellular carcinoma) was as the same as those in patients with chronic hepatitis type B and C. Our results indicated a low prevalence of non-A to G chronic hepatitis, yet a few cases were progressive to cirrhosis or HCC, and this may be due to another unknown agents for non-A to G hepatitis.

Adult↗
PubMed1999

[TT virus infection in an area of high-endemicity for hepatitis C].

TT virus (TTV) was recently identified as a candidate for a new hepatitis virus. In the present study, the clinical features and transmission routes of TTV infection were analyzed in an area highly endemic for hepatitis C virus (HCV) infection, and compared to those in an area not endemic. In conclusion, the prevalence of TTV infection was as high as 58% in the high-endemicity area for HCV infection. The main transmission route for TTV appeared to be different from that of HCV and HGV. TTV infection showed a reciprocal association with HCV infection, and had limited pathogenetic effect on hepatitis.

Adult↗
PubMed1999

[Hepatitis E virus].

Explore the source record for details and available documents.

Hepatitis Antibodies↗
PubMed1999

Age- and sex-related changes in toluene metabolism by rat hepatic microsomes in vitro.

Age- and sex-related changes in toluene metabolism by hepatic microsomes of male and female Sprague-Dawley (SD) rats (1 to 20 weeks) were investigated. A major metabolite of toluene, benzyl alcohol (BA), was measured by high-performance liquid chromatography (HPLC). At low substrate toluene concentrations (0.4 mM), in male rats, BA increased dramatically with development, reaching a peak at 5 weeks of age, rapidly decreasing thereafter. In female rats, BA increased dramatically with development at 3 to 5 weeks of age, and then declined gradually to a low level. Gender differences were obtained at 5 and 20 weeks of age, with BA products being higher in males than in females. At high substrate toluene concentrations (5.0 mM), in male rats, the BA formation pattern was similar to that at the low substrate concentration, although the rate of increase with age was slower. In female rats, a peak was obtained at 3 weeks of age, and then declined gradually to a low level. Gender differences were obtained at 5, 15 and 20 weeks of age, with BA products being higher in males than in females. These results indicate that toluene metabolism exhibits age and gender differences.

Aging↗
PubMed1998

Sanitary status of oocytes and embryos collected from heifers experimentally exposed to Leptospira borgpetersenii serovar hardjobovis.

In a preliminary trial and three experiments, a total of 30 Holstein heifers were experimentally infected with a culture of Leptospira borgpetersenii serovar hardjobovis via one or more routes (uterine, cervical supraconjunctival, intranasal) and oviductal and uterine fluids recovered post-mortem or in vivo following superovulation with FSH. All routes of administration were effective in establishing Leptospira infection in the reproductive tract and Leptospira were identified in the oviductal and uterine fluids of all 30 heifers by microscopy. The incidence of infection was confirmed by positive identification of serum antibodies by the microscopic agglutination test (MAT). Twenty-one samples of the embryos (n = 59) recovered were cultured using bacteriological procedures and all tested negative for the infectious microorganism. Using polymerase chain reaction (PCR) assay, however, showed that 29% (7/24) of morula and blastocyst stage embryos, and one out of 29 oocytes tested positive for the presence of leptospiral DNA. A single oocyte or embryo collected from the infected heifers was inoculated intravenously to 26 test heifers. None of the test heifers developed antibody titers to Leptospira. It was concluded that, despite the presence of leptospires in the reproductive tract of donor animals and the association of leptospiral DNA with uterine stage embryos, the transmission of this disease is unlikely to occur by transfer of in vivo produced embryos in the bovine.

Animals↗
PubMed1998

New platelet fibrinogen receptor glycoprotein IIb-IIIa antagonists: orally active series of N-alkylated amidines with a 6,6-bicyclic template.

The design, synthesis, and pharmacological evaluation of (S)-(-)-ethyl [6-[4-(morpholinoformimidoyl)benzamido]-3, 4-dihydro-2H-1-benzopyran-3-yl]acetate hydrochloride ((S)-4.HCl, MS-180), an orally active glycoprotein IIb-IIIa (GPIIb-IIIa) antagonist, are reported. Pharmacophore mapping of amidino and carboxyl groups of already known GPIIb-IIIa antagonists led to the synthesis of nine amidino acids containing 6,6-bicyclic ring skeletons (10a-i). Among them, the compounds 10a,c,e having an amide bond and 1,2,3,4-tetrahydronaphthalene or 3, 4-dihydro-2H-1-benzopyran skeleton showed marked inhibitions with IC50 values of 46-57 nM in human platelet aggregation assay in vitro, but low oral activities. N-Alkylation of the amidino group coupled with the ester prodrug approach afforded MS-180 ((S)-4.HCl), which generates in vivo the corresponding carboxylic acid (S)-3 as an active species. In vitro, (S)-3 inhibited ADP-induced aggregation of guinea pig, dog, and human platelets (IC50 = 110, 253, and 35 nM, respectively) and inhibited the binding of fibrinogen to immobilized GPIIb-IIIa of human platelets (IC50 = 0.12 nM). After oral administration of MS-180 ((S)-4.HCl) to fasted beagle dog, ex vivo inhibition of platelet aggregation was observed. The maximal inhibitions were observed 2-4 h after dosing with dose dependency (60% inhibition at a dose of 1 mg/kg, 85% at 3 mg/kg, and 100% at 10 mg/kg, respectively) and the extent of the inhibitions paralleled the plasma concentration of the active species (S)-3. On the basis of these studies, we selected MS-180 ((S)-4.HCl) as a candidate for clinical evaluation as a drug for the treatment and prevention of thrombosis in patients.

Acetates↗
PubMed1998

Endothelium-dependent relaxation of collateral microvessels after intramuscular gene transfer of vascular endothelial growth factor in a rat model of hindlimb ischemia.

BACKGROUND: Recent investigations have demonstrated the ability of vascular endothelial growth factor (VEGF) to augment the development of collateral arteries in vivo. In vitro studies have suggested that the use of VEGF also improves the endothelium-dependent relaxation of collaterals at the microvascular level. The purpose of this study was to determine in vivo the extent to which vasomotor responses of collateral microvessels are altered after VEGF treatment. METHODS AND RESULTS: Ischemia was induced in the hindlimb of 35 rats by excision of the femoral artery. Immediately thereafter, 400 microg of a plasmid encoding VEGF or ss-galactosidase (control) was transfected into limb muscles. Four weeks later, synchrotron radiation microangiography, with a spatial resolution of 30 microm, was performed to document the reactivity of collateral microvessels. Administration of the endothelium-dependent vasodilator acetylcholine failed to induce dilation of collateral microvessels in control animals. By contrast, profound dilation of collaterals was observed after acetylcholine in VEGF-treated animals. This response was evident in vessels with a linear appearance but not in those with an undulating appearance. The resulting blood flow in the ischemic limb after administration of acetylcholine in the control animals was only 64.6+/-17.0% of that of the contralateral normal limb, whereas blood flow was augmented to 106.1+/-8.4% in VEGF-treated animals (P<0.05). CONCLUSIONS: These results demonstrate in vivo that the use of VEGF restores impaired vasomotor responses in some types of collateral microvessels, which may help to provide a basis for understanding the microcirculation after therapeutic angiogenesis with VEGF.

Acetylcholine↗
PubMed1998

High-spatial-resolution and real-time medical imaging using a high-sensitivity HARPICON camera.

A HARPICON(TM) camera has been applied to a digital angiography system with fluorescent-screen optical-lens coupling. It uses avalanche multiplication in the photoconductive layer for high-sensitivity imaging. The limiting spatial resolutions in the 1050 scanning-line mode of the camera are about 30 and 50 micro m at input field sizes of 20 x 20 and 50 x 50 mm on the screen, respectively. For high-speed imaging, the 525 scanning-line mode at a rate of 60 images s(-1) can be selected. High-quality images of coronary arteries in dogs were obtained by intra-aortic coronary angiography and superselective coronary angiography using a single-energy X-ray above the iodine K-edge energy.

Journal Article↗
PubMed1998

High dose rate versus low dose rate interstitial radiotherapy for carcinoma of the floor of mouth.

PURPOSE: Patients with cancer of the floor of mouth are treated with radiation because of functional and cosmetic reasons. We evaluate the treatment results of high dose rate (HDR) and low dose rate (LDR) interstitial radiation for cancer of the floor of mouth. METHODS AND MATERIALS: From January 1980 through March 1996, 41 patients with cancer of the floor of mouth were treated with LDR interstitial radiation using 198Au grains, and from April 1992 through March 1996 16 patients with HDR interstitial radiation. There were 26 T1 tumors, 30 T2 tumors, and 1 T3 tumor. For 21 patients treated with interstitial radiation alone, a total radiation dose of interstitial therapy was 60 Gy/10 fractions/6-7 days in HDR and 85 Gy within 1 week in LDR. For 36 patients treated with a combination therapy, a total dose of 30 to 40 Gy of external radiation and a total dose of 48 Gy/8 fractions/5-6 days in HDR or 65 Gy within 1 week in LDR were delivered. RESULTS: Two- and 5-year local control rates of patients treated with HDR interstitial radiation were 94% and 94%, and those with LDR were 75% and 69%, respectively. Local control rate of patients treated with HDR brachytherapy was slightly higher than that with 198Au grains (p = 0.113). For late complication, bone exposure or ulcer occurred in 6 of 16 (38%) patients treated with HDR and 13 of 41 (32%) patients treated with LDR. CONCLUSION: HDR fractionated interstitial brachytherapy can be an alternative to LDR brachytherapy for cancer of the floor of mouth and eliminate radiation exposure for the medical staff.

Adult↗
PubMed1998

Intracellular acidification induced by membrane depolarization in rat hippocampal slices: roles of intracellular Ca2+ and glycolysis.

To elucidate the mechanism of pHi changes induced by membrane depolarization, the variations in pHi and [Ca2+]i induced by a number of depolarizing agents, including high K+, veratridine, N-methyl-D-aspartate (NMDA) and ouabain, were investigated in rat hippocampal slices by the fluorophotometrical technique using BCECF or fura-2. All of these depolarizing agents elicited a decrease in pHi and an elevation of intracellular calcium ([Ca2+]i) in the CA1 pyramidal cell layer. The increases in [Ca2+]i caused by the depolarizing agents almost completely disappeared in the absence of Ca2+ (0 mM Ca2+ with 1 mM EGTA). In Ca2+ free media, pHi acid shifts produced by high K+, veratridine or NMDA were attenuated by 10-25%, and those produced by ouabain decreased by 50%. Glucose-substitution with equimolar amounts of pyruvate suppressed by two-thirds the pHi acid shifts induced by both high K+ and NMDA. Furthermore, lactate contents were significantly increased in hippocampal slices by exposure to high K+, veratridine or NMDA but not by ouabain. These results suggest that the intracellular acidification produced by these depolarizing agents, with the exception of ouabain, is mainly due to lactate accumulation which may occur as a result of accelerated glycolysis mediated by increased Na+-K+ ATPase activity. A Ca2+-dependent process may also contribute to the intracellular acidification induced by membrane depolarization. Since an increase in H+ concentration can attenuate neuronal activity, glycolytic acid production induced by membrane depolarization may contribute to the mechanism that prevents excessive neuronal excitation.

Acids↗
PubMed1998

Different personalities between depression and anxiety.

We examined the different personality dimensions between depression and anxiety with Cloninger's seven-factor model of temperament and character. The Temperament and Character Inventory (TCI), which measures four temperament and three character dimensions of Cloninger's personality theory (125-item short version), the Self-rating Depression Scale (SDS), and the State-Trait Anxiety Inventory (STAI) were administered to 223 Japanese students. With hierarchical regression analysis, the SDS score was predicted by scores of Harm-Avoidance, Self-Directedness, and Self-Transcendence, even after controlling for the STAI score. The STAI score was predicted by scores of Self-Directedness and Cooperativeness, even after controlling for the SDS score. More importance should be attached to these dimensions of character because they might contribute to both depression and anxiety.

Adolescent↗
PubMed1998

Sero-epidemiologic study of hepatitis C virus infection in Fukuoka, Japan.

We conducted an epidemiological study of 509 residents of H town, Fukuoka, Japan, to investigate the high mortality rate from liver disease. Antibodies to hepatitis C virus (HCV) (anti-HCV) were detected in 120 residents (23.6%); HCV RNA in 91 (17.9%), and hepatitis B surface antigen (HBsAg) in 13 (2.6%). Multivariate logistic regression analyses showed that presence of anti-HCV, male gender, and history of liver disease were associated with the presence of liver dysfunction, and that age of more than 40 years and a particular district were associated with the presence of anti-HCV. HCV RNA was more frequently detected in anti-HCV-positive men than women (41, or 85.4% versus 50, or 69.4%) (P < 0.05). The incidence of liver dysfunction was significantly higher in HCV RNA-positive men than women (32, or 66.7% versus 22, or 30.6%) (P < 0.05). These findings suggest that: (1) HCV was correlated with the high mortality rate from liver diseases, (2) there were district-related differences in the incidence of HCV, and (3) the lower frequency of elimination of HCV from men may explain why they showed a high mortality from liver disease.

Adult↗
PubMed1998

Two patients with acute hepatitis B with suspected sexual transmission of hepatitis G virus.

Two patients with acute hepatitis B with suggested sexual transmission of hepatitis G virus (HGV) are reported. A total of 18 patients with community acquired acute hepatitis B were analyzed in this study. Two of the 18 patients (patients 1 and 2) were positive for serum HGV RNA at the initial consultation. Both patients had had sexual contact with prostitutes several weeks before the onset of acute hepatitis, and hepatitis B virus (HBV) was suggested to be infected through the sexual contacts. These patients showed no other history of exposure to possible transmission routes for blood-borne hepatitis viruses. Patient 1 was diagnosed as with acute HGV infection because the antibody to HGV envelope-2 protein seroconverted to positive during the course of acute hepatitis. HGV RNA was negative in a serum sample collected from patient 2 before the onset of acute hepatitis, also suggesting acute HGV infection. These results indicate that in patients 1 and 2 HGV was infected along with HBV through sexual contact. The clinical manifestations of acute hepatitis in the two patients with HGV co-infection did not differ from those in the 16 patients with HBV infection alone.

Adolescent↗
PubMed1998

Clinical application of hepatitis C virus core protein in early diagnosis of acute hepatitis C.

A fluorescence enzyme immunoassay (FEIA) for the quantitative measurement of hepatitis C virus (HCV) core protein has recently been developed. In this study, we studied the clinical usefulness of this measurement in patients with acute hepatitis C. Eighteen patients with post-transfusion acute hepatitis C were enrolled in the study; 5 patients showed resolution of hepatitis with disappearance of HCV viremia, while the remaining 13 patients did not. A second generation HCV antibody, HCV RNA, and HCV core protein were measured in serial serum samples taken within 1 month of the onset of acute hepatitis and 3, 6, 12, 24, and 36 months after onset. Within the first month after disease onset, the positivity rates of HCV RNA (100%; P = 0.0014) and HCV core protein (89%; P = 0.0300) were both significantly higher than that of HCV antibody (56%). Six months after disease onset, the positivity rate of HCV antibody had increased, to 100%, and the positivity rates of HCV RNA and HCV core protein began to decrease. HCV core protein levels did not differ between patients with resolved and unresolved disease in the first month after disease onset. These findings indicate that FEIA, a simple assay, for the measurement of HCV core protein was useful for the early diagnosis of acute hepatitis C.

Acute Disease↗