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Biomedical subjects

K Takeuchi

Publications and source records attributed to K Takeuchi.

At least 451 records · Page 25Linked to original sources
PubMed1998

Assessment of cardiac function and gene expression at an early phase after myocardial infarction.

The purpose of this study was to examine left ventricular function and cardiac gene expressions at an acute phase after myocardial infarction (MI). MI was induced in rats by ligation of the left coronary artery. Two days after MI, we performed Doppler-echocardiography and measured the systolic and diastolic function. We then analyzed the contractile protein and extracellular matrix mRNAs of cardiac tissues in the infarcted region, including the adjacent noninfarcted myocardium (the adjacent noninfarcted myocardium) and the remote noninfarcted myocardium, by Northern blot hybridization. Fractional shortening decreased significantly to 28%. Peak early diastolic filling wave (E wave) velocity increased in MI rats (MI; 90 +/- 3 cm/s versus the control; 71 +/- 2 cm/s, p < 0.05), and the deceleration rate of the E wave velocity was more rapid in MI rats (MI; 22.0 +/- 2.6 m/s2 versus the control; 16.5 +/- 2.0 m/s2, p < 0.01). Atrial filling wave (A wave) velocity decreased, resulting in a marked increase in the ratio of E wave to A wave velocity (MI; 3.1 +/- 0.3 versus the control; 2.1 +/- 0.2, p < 0.01). In the adjacent noninfarcted myocardium, mRNA levels for alpha-skeletal actin, atrial natriuretic polypeptide (ANP), transforming growth factor-beta 1(TGF-beta 1), fibronectin, and collagen types I and III increased significantly. In the remote noninfarcted myocardium, mRNA levels for alpha-skeletal actin, ANP, and collagen types I and III increased, while mRNA levels for beta-myosin heavy chain, TGF-beta 1 and fibronectin did not change. We observed left ventricular dysfunction and different gene expression between adjacent noninfarcted myocardium and in the remote noninfarcted myocardium two days after MI. These findings suggest that cardiac gene expression after MI may be a compensation reaction for cardiac dysfunction induced by myocardial damage.

Animals↗
PubMed1998

Evaluation of rheumatoid arthritis using a scoring system devised from magnetic resonance imaging of rheumatoid knees.

We studied the magnetic resonance imaging (MRI) of 120 knees in 86 rheumatoid arthritis (RA) patients and of 14 unaffected knees in 12 control cases. We also developed a scoring system as a quantitative analysis method. We divided the MRI into 10 items, and classified the severity of the symptoms into 4 grades (score 0 to 3). The average total score increased according to the radiographic grade. Soft tissue lesions were clearly detected, even in the early stages of RA. Items such as synovial proliferation showed a high score even in the early stages, suggesting that it was the initial symptom of RA. The score also showed a correlation with the inflammatory signs. These results suggest that this scoring system is very sensitive and yields a good reflection of RA activity. We demonstrated that this system is simple and convenient for routine diagnostic use. We further demonstrated that it is useful for following the advancement of RA and for evaluating the response to treatment.

Adult↗
PubMed1998

Results of surgical treatment for ossification of the posterior longitudinal ligament of the thoracic spine.

Conservative treatment is ineffective for ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine, and surgical treatment is indicated for most cases, while such cases are not often experienced. In the present study, the results of surgical management involving mainly posterior decompression for this disease were evaluated clinically. The study included 9 patients (1 man and 8 women) who underwent surgical treatment for OPLL of the thoracic spine between 1984 and 1993. Laminectomy was performed in 5 patients, and laminectomy plus anterior decompression of the OPLL via the posterior approach based on Otsuka's method was performed in 2 patients. In 1 patient, laminoplasty for OPLL of the cervical spine was combined with laminectomy of the symptomatic lesion in the thoracic spine. One patient underwent anterior decompression and fusion. The results were evaluated using the Japanese Orthopaedic Association score (JOA score) and recovery rate. The postoperative follow-up period ranged from 1 year to 10 years and 3 months (mean, 4 years and 6 months). The mean JOA score was 4.8 before surgery and improved to 7.6 at the final examination. This was a mean recovery rate of 50.1%. Symptoms caused by OPLL in the thoracic spine can be alleviated by posterior decompression where OPLL extends from the upper to the middle thoracic spine or extends from the middle to the lower thoracic spine. It seems, however, that OPLL localized to the middle thoracic spine requires anterior decompression.

Adult↗
PubMed1998

Persistence of Escherichia coli O157:H7 in dairy fermentation systems.

We examined (i) the persistence of Escherichia coli O157:H7 as a postpasteurization contaminant in fermented dairy products; (ii) the ability of E. coli O157:H7 strains with and without the general stress regulatory protein, RpoS, to compete with commercial starter cultures in fermentation systems; and (iii) the survival of E. coli O157:H7 in the yogurt production process. In commercial products inoculated with 10(3) CFU/ml, E. coli O157:H7 was recovered for up to 12 days in yogurt (pH 4.0), 28 days in sour cream (pH 4.3), and at levels > 10(2) CFU/ml at 35 days in buttermilk (pH 4.1). For the starter culture competition trials, the relative inhibition of E. coli O157:H7 in the experimental fermentation systems was, in decreasing order, thermophilic culture mixture, Lactobacillus delbrueckii subsp. bulgaricus R110 alone, Lactococcus lactis subsp. lactis D280 alone, Lactococcus lactis subsp. cremoris D62 alone, and Streptococcus thermophilus C90 alone showing the least inhibition. Recovery of the rpoS mutant was lower than recovery of its wild-type parent by 72 h or earlier in the presence of individual starter cultures. No E. coli O157:H7 were recovered after the curd formation step in yogurt manufactured with milk inoculated with 10(5) CFU/ml. Our results show that (i) postprocessing entry of E. coli O157:H7 into fermented dairy products represents a potential health hazard; (ii) commercial starter cultures differ in their ability to reduce E. coli O157:H7 CFU numbers in fermentation systems; and (iii) the RpoS protein appears to most effectively contribute to bacterial survival in the presence of conditions that are moderately lethal to the cell.

Animals↗
PubMed1998

Changes in the proliferative activities of cells in experimental atherosclerotic plaques during remodeling.

To investigate the relationship between cytologic alterations and cellular proliferation during atherosclerotic remodeling, we examined experimental atheromatous plaques by immunohistochemistry. Plaques were formed on rabbit aortas by cholesterol-enriched diets and mechanical stimulation over a period of 2 months. Plaques were examined 1 month and 6 months after induction. We used antibodies RAM-11, HHF-35, and monoclonal anti-proliferating cell nuclear antigen (PCNA) antibody for detection of macrophages (Mphi), smooth muscle cells (SMC), and PCNA, respectively. One month after induction, the plaques revealed a thickened intima with a fibrofatty histologic pattern or accumulation of foam cells. With either histologic pattern, foam cells were found to be Mphi and proliferative activity was mainly observed in Mphi. Six months after induction, calcification and organization were seen on the induced plaques, suggesting progression of remodeling. There were fewer Mphi and more SMC compared with plaques examined 1 month after induction. Proliferative activity was observed mainly in SMC. We have demonstrated that the proliferative activity of cell types changes during remodeling of atheromatous plaques. Our results suggest an important relationship between the proliferative activity of SMC and remodeling.

Animals↗
PubMed1998

Cyclooxygenase-2 selective and nitric oxide-releasing nonsteroidal anti-inflammatory drugs and gastric mucosal responses.

Occurrence of gastrointestinal damage and delayed healing of pre-existing ulcer are commonly observed in association with clinical use of nonsteroidal antiinflammatory drugs (NSAIDs). We examined the effects of NS-398, the cyclooxygenase (COX)-2 selective inhibitor, and nitric oxide (NO)- releasing aspirin (NCX-4016) on gastric mucosal ulcerogenic and healing responses in experimental animals, in comparison with those of nonselective COX inhibitors such as indomethacin and aspirin. Indomethacin and aspirin given orally were ulcerogenic by themselves in rat stomachs, while either NS-398 or NCX-4016 was not ulcerogenic at the doses which exert the equipotent antiinflammatory action with indomethacin or aspirin. Among these NSAIDs, only NCX-4016 showed a dose-dependent protection against gastric lesions induced by HCl/ethanol in rats. On the other hand, the healing of gastric ulcers induced in mice by thermal-cauterization was significantly delayed by repeated administration of these NSAIDs for more than 7 days, except NCX-4016. Gastric mucosal prostaglandin contents were reduced by indomethacin, aspirin and NCX-4016 in both normal and ulcerated mucosa, while NS-398 significantly decreased prostaglandin generation only in the ulcerated mucosa. Oral administration of NCX-4016 in pylorus-ligated rats and mice increased the levels of NO metabolites in the gastric contents. In addition, both NS-398 and NCX-4016 showed an equipotent anti-inflammatory effect against carrageenan-induced paw edema in rats as compared with indomethacin and aspirin. These results suggest that both indomethacin and aspirin are ulcerogenic by themselves and impair the healing of pre-existing gastric ulcers as well. The former action is due to inhibition of COX-1, while the latter effect may be accounted for by inhibition of COX-2 and mimicked by NS-398, the COX-2 selective NSAID. NCX-4016, despite inhibiting both COX-1 and COX-2, protects the stomach against damage and preserves the healing response of gastric ulcers, probably because of the beneficial action of NO.

Animals↗
PubMed1998

Biochemical investigation of cell motile activity in rheumatoid synovial fluid.

OBJECTIVE: We have suggested that autocrine motility-like factor is expressed in rheumatoid synovial fluid (SF). We examined the biochemical features of the motile activity. METHODS: We investigated chemokinetic activities of SF from patients with osteoarthritis and joint trauma as well as rheumatoid arthritis (RA) using a unique protein-free culture fibrosarcoma system. We then investigated biochemical features and the signal transduction pathway of the motile activity expressed in RA. RESULTS: We found chemokinetic activity in SF from all patients. However, ability to block binding of the monoclonal antibody to the receptor for autocrine motility factor (AMF) was observed only in rheumatoid SF on immunoblots. Biochemical investigation indicated motile activity to be heat labile, trypsin sensitive, and eluted at high salt concentration from an anion exchange column. Stimulated motility of rheumatoid SF was inhibited by the pertussis toxin, staurosporine (C kinase inhibitor), and genistein (tyrosine kinase inhibitor), but not by A kinase inhibitor, H-8. CONCLUSION: The cell motility activity expressed in rheumatoid SF appears to be AMF, and the cytokine may be essential for communication among leukocytes in rheumatic disease.

Animals↗
PubMed1998

Prenatal diagnosis of fetal urogenital abnormalities with oligohydramnios by magnetic resonance imaging using turbo spin echo technique.

Turbo spin echo technique is a sequence that enables T2 weighted magnetic resonance (MR) images to be obtained in a few seconds. The purpose of this study is to evaluate the usefulness of this sequence in the prenatal diagnosis of fetal urogenital abnormalities associated with oligohydramnios, which make the ultrasound examination inconclusive. Two fetuses suspected of having prune belly syndrome and polycystic kidney on ultrasound examination were studied by MR imaging using turbo-spin echo method in utero. The images were compared with prenatal ultrasonography or post-mortem findings. In both fetuses, abnormalities were diagnosed correctly. This sequence is useful because it provides images of diagnostic quality in a very short scanning time.

Adult↗
PubMed1998

Expression of costimulatory molecule CD80 on peripheral blood T cells in patients with systemic lupus erythematosus.

OBJECTIVE: To investigate the expression of costimulatory molecule CD80 on T cells of peripheral blood mononuclear cells (PBMC) in patients with systemic lupus erythematosus (SLE). METHODS: Monoclonal antibodies against CD80 were used for flow cytometry and expression of CD80 on PBMC was studied in 26 patients with SLE, 18 patients with rheumatoid arthritis (RA), 8 patients with mixed connective tissue disease (MCTD), and 22 healthy controls. RESULTS: CD80 was detected on CD3+ and CD19+ cells in patients with SLE and it was significantly higher than that of controls. In patients with SLE CD80 was expressed on CD4+ T cells (8.05+/-5.45%), significantly higher than in RA and controls, but was not highly expressed on CD8+ T cells (1.67+/-2.87%). CD80+CD4+ T cell phenotype analysis revealed CD45RA-, CD45RO+, and CD25+, or HLA-DR+ activated T cells. The percentage of CD80+ cells in CD4+ cells increased in the active stage of SLE, and was significantly correlated with the SLE disease activity index. CONCLUSION: CD80 can be expressed on activated CD4+ T cells in PBMC of patients with SLE in vivo and the appearance of these cells is associated with the disease activity in SLE.

Antibodies, Monoclonal↗
PubMed1998

Effect of nitric oxide-releasing aspirin derivative on gastric functional and ulcerogenic responses in rats: comparison with plain aspirin.

The effects of a nitric oxide (NO)-releasing derivative of aspirin, NCX-4016, on gastric functional and ulcerogenic responses in rat stomachs were examined in comparison with those of aspirin. Topical application of aspirin (80 mM) to the stomach markedly decreased transmucosal potential difference and slightly increased luminal pH (acid back-diffusion) with minimal effect on mucosal blood flow, whereas NCX-4016 caused a marked increase in mucosal blood flow with no effect on potential difference and pH. Aspirin itself was ulcerogenic, causing damage in the mucosa when administered p.o., and it markedly potentiated gastric ulcerogenic response to hypothermic stress (28 degrees C-30 degrees C) with no effect on acid secretion when given s.c. NCX-4016, however, was not ulcerogenic by itself, did not modify the ulcerogenic response to stress and even showed a dose-dependent protection against HCl/ethanol-induced gastric lesions. When NCX-4016 was given intragastrically to pylorus-ligated rats, a large amount of NO was detected in both gastric contents and serum. NCX-4016 administered either p.o. or s.c. produced an equipotent inhibition of mucosal PGE2 generation in the stomach, as compared with aspirin. In addition, both aspirin and NCX-4016 suppressed carrageenan-induced rat paw edema. These results suggest that, unlike aspirin, the NO-releasing derivative of aspirin NCX-4016 neither had a topical irritating action on the stomach nor exerted a worsening effect on gastric ulcerogenic response to stress, but rather provided gastric protection against ethanol, despite inhibiting cyclo-oxygenase activity and showing anti-inflammatory action much as aspirin does. NCX-4016, probably by releasing NO, exerted protective effects that counteracted the potential damaging effects of cyclo-oxygenase inhibition.

Animals↗
PubMed1998

Regional cerebral blood flow evaluated by 99mTc-HMPAO-SPECT in patients with axillo-axillary bypass for subclavian steal syndrome.

BACKGROUND: Clear evidence of cerebral blood circulation has not been shown after axillo-axillary bypass surgery in patients with subclavian steal syndrome. METHODS: We investigated the cerebral circulation and blood flow in 3 patients receiving axillo-axillary bypass by RI angiography using 99mTc-dl hexamethyl propylene amine oxime (99mTc-HMPAO). Two patients had vertebral basilar cerebral symptoms which were related to decreased cerebral blood flow evidenced by 99mTc-HMPAO. RESULTS: After the correction, cerebral symptoms disappeared and improved cerebral blood circulation detected by 99mTc-HMPAO-SPECT. CONCLUSIONS: We concluded that axillo-axillary bypass was a fairly effective procedure to improve cerebral blood circulation evidenced by 99mTc-HMPAO-SPECT.

Axillary Artery↗
PubMed1998

Relation between the kinetics of thallium-201 in myocardial scintigraphy and myocardial metabolism in patients with acute myocardial infarction.

OBJECTIVE: To investigate the relations between myocardial metabolism and the kinetics of thallium-201 in myocardial scintigraphy. METHODS: 46 patients within six weeks after the onset of acute myocardial infarction underwent resting myocardial dual isotope, single acquisition, single photon emission computed tomography (SPECT) using radioiodinated 15-iodophenyl 3-methyl pentadecaenoic acid (BMIPP) and thallium-201, exercise thallium-201 SPECT, and positron emission tomography (PET) using nitrogen-13 ammonia (NH3) and [F18]fluorodeoxyglucose (FDG) under fasting conditions. The left ventricle was divided into nine segments, and the severity of defects was assessed visually. RESULTS: In the resting SPECT, less BMIPP uptake than thallium-201 uptake was observed in all of 40 segments with reverse redistribution of thallium-201, and in 21 of 88 segments with a fixed defect of thallium-201 (p < 0.0001); and more FDG uptake than NH3 uptake (NH3-FDG mismatch) was observed in 35 of 40 segments with reverse redistribution and in 38 of 88 segments with fixed defect (p < 0.0001). Less BMIPP uptake in the resting SPECT was observed in 49 of 54 segments with slow stress redistribution in exercise SPECT, and in nine of 17 segments with rapid stress redistribution (p < 0.0005); NH3-FDG mismatch was observed in 42 of 54 segments with slow stress redistribution and in five of 17 segments with rapid stress redistribution (p < 0.0005). CONCLUSIONS: Thallium-201 myocardial scintigraphy provides information about not only myocardial perfusion and viability but also about myocardial metabolism in patients with acute myocardial infarction.

Adult↗
PubMed1998

Two cases of primary pulmonary hypertension diagnosed during pregnancy.

Primary pulmonary hypertension (PPH) is a rare clinical entity with a high mortality in pregnancy, delivery and postpartum. This paper describes two clinical cases of PPH diagnosed in pregnancy with different severity and outcomes; Case 1 was diagnosed as PPH at 34 weeks of gestation with pulmonary arterial pressure of 60 mmHg and delivered successfully by cesarean section with uneventful postoperative course. Case 2 was diagnosed as PPH at 26 weeks of gestation with pulmonary arterial pressure of 120 mmHg and delivered by cesarean section but died on the 7th day after the operation because of serious and progressive pulmonary hypertension. Patients with primary pulmonary hypertension should avoid pregnancy because of the high mortality, although some cases including ours have been reported with positive outcome.

Adult↗
PubMed1998

[Trial of new intraocular lens power calculation following phototherapeutic keratectomy].

We reviewed the SRK-II method and introduce a new equation to calculate the intraocular lens (IOL) power for eyes which underwent laser phototherapeutic keratectomy (PTK). The Gullstrand series was used to determine the power and the radius of curvature of planoconvex IOLs which alter the focal point from the cornea to reach the conjugate point on the retina. The radius of anterior corneal curvature (R), axial length (AXL), predicted postoperative anterior chamber depth (ACD), and lens thickness (LT) were employed in the following formula to calculate the IOL refractive power: K = R/7.7, DC = 337. 5/R, VC = 1,000/DC*1.336 where VC is the posterior vertex focal length. A1 = -(VC-ACD), B1 = AXL-0.5* K-ACD-0. 103 LT, S = 1/A1 + 1/B1; this determined the diopter (D) of IOL in liquid to be (D) = 1,000/(1/S)* 1.336. In eyes which underwent PTK, the keratometric value prior to cataract surgery was not applied. Instead, R' defined as R-dT, where R is the radius of corneal curvature prior to PTK and dT the amount of corneal tissue removed, was introduced. Further, the corneal thickness before cataract surgery (CT') was defined as CT-dT where CT is the corneal thickness prior to PTK. Although it is important to select a lens that has an acurate predicted anterior chamber depth, the new equation appears to be more useful than the SRK-II formula.

Cataract Extraction↗
PubMed1998

[Clinical evaluation as palliative therapy of combination chemotherapy with continuous infusional 5-fluorouracil and consecutive low-dose cisplatin in unresectable gastrointestinal carcinoma].

Combination chemotherapy with continuous infusion 5-FU, 350 mg/m2/day and low-dose CDDP between 5 to 10 mg/body/day (day 1-5) was evaluated in 46 patients with unresectable gastric (34), colorectal (10) and biliary tract (2) carcinoma. This regimen was repeated for 4 weeks. The overall response rate was 45.7% (21/46), but the resectable rate was only 10.9% (5/46). Toxic response (> grade 2) was 22% (10/46). After chemotherapy, the patients preserved good performance status and quality of life. Median survival time was about 11 months, and there was no significant difference between CR or PR cases and NC one. Survival time of patients correlated not to the reduction rate of tumor but to conditions of hosts (e.g., performance status, quality of life). These results suggested that this therapy is an effective palliative chemotherapy for patients with unresectable gastrointestinal carcinoma.

Adult↗
PubMed1998

[Pneumonia caused by granulomatous Pneumocystis carinii in a patient with the acquired immunodeficiency syndrome].

A 54-year-old man was admitted to the hospital because of fever and general fatigue. A chest roentgenogram on admission showed lobular opacities and ill-defined opacities in both lower lobes. The pneumonia was successfully treated with antibiotics. The acquired immunodeficiency syndrome was diagnosed because ELISA and PCR tests for antibodies to the human immunodeficiency virus were positive and the CD 4+ lymphocyte count was 39 per cubic millimeter. Examination of bronchoalveolar lavage fluid revealed no Pneumocystis carinii. Trimethoprim and sulfamethoxazole were given prophylactically, but were withdrawn because of a rash. The patient began to receive aerosolized pentamindine and was discharged. On the next day, he was readmitted to the hospital because of a high fever. A chest roentgenogram showed diffuse miliary opacities. Chest CT scan also showed diffuse small nodular opacities in both lungs. Examination of a transbronchial biopsy specimen revealed well-defined, noncaseating granulomas with pneumocystis organisms in their centers. Cultures for tuberculosis and fungi were all negative. We diagnosed granulomatous pneumonia caused by Pneumocystis carinii, which is an atypical manifestation of Pneumocystis carinii pneumonia. The patient died of sepsis and cardiac tamponade. Microscopically, the lung tissue was found to have foamy intra-alveolar exdates, which is a typical histological feature of Pneumocystis carinii pneumonia.

AIDS-Related Opportunistic Infections↗