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Biomedical subjects

T Seki

Publications and source records attributed to T Seki.

At least 397 records · Page 22Linked to original sources
PubMed1993

Neurological manifestations of hemorrhagic colitis in the outbreak of Escherichia coli O157:H7 infection in Japan.

An outbreak of hemorrhagic colitis associated with Escherichia coli O157:H7 occurred in a kindergarten in Saitama, Japan from September to November, 1990. Seven patients admitted to our hospital showed neurological manifestations: generalized seizures, impaired consciousness, urinary incontinence, gaze nystagmus, phrenic nerve palsy, action tremor and vertigo. Two patients died. On the basis of the clinical courses and laboratory findings of the seven patients and postmortem findings of one case, these neurological symptoms were suspected to be induced by the verotoxin elaborated by Escherichia coli O157:H7.

Bacterial Toxins↗
PubMed1993

Effect of some alkaloids, flavonoids and triterpenoids, contents of Japanese-Chinese traditional herbal medicines, on the lipogenesis of sebaceous glands.

The effects of some alkaloids and flavonoids, which are major ingredients in some of the Japanese Kampoh drugs (Japanese-Chinese traditional herbal medicines) experientially known to be efficacious for the treatment of acne vulgaris, on the lipogenesis in the sebaceous glands of the hamster ear, an excellent animal model for the human sebaceous gland, were studied. Lipogenesis was assayed by determining 14C incorporation into sebaceous lipids extracted from the sebaceous glands which were preincubated with 14C-acetate. We found that the lipogenesis in the hamster sebaceous glands was suppressed 63 and 54% by 10(-4) M berberine (an alkaloid) and wogonin (a flavonoid), respectively. We suggest that the therapeutic effects of some Japanese Kampoh drugs experimentally used for acne vulgaris could be due to inhibition of lipogenesis by their active ingredients such as berberine and wogonin.

Alkaloids↗
PubMed1993

Retinals and retinols induced by estrogen in the blood plasma of Xenopus laevis.

Injection of estrogen into male Xenopus laevis induced the appearance of retinals (retinal and 3-dehydroretinal) and a considerable increase in the amount of retinols (retinol and 3-dehydroretinol) in the blood plasma. These retinoids were mainly in the all-trans form. Without estrogen injection, retinols were normally found in the blood plasma of both males and females, but only trace amounts of retinals were detected and these were restricted to the plasma of females. The proteins in the blood plasma of estrogen-injected males were separated into two fractions. One fraction included vitellogenin, the precursor of egg yolk proteins, and the other contained some plasma proteins other than vitellogenin. Retinals were detected in the former and retinols in the latter. It is suggested that retinals are bound to vitellogenin and are taken up into oocytes in the process of vitellogenesis.

Animals↗
PubMed1993

Influence of composition of l-menthol-ethanol-water ternary solvent system on the transdermal delivery of morphine hydrochloride.

The influence of concentration of each component in l-menthol-ethanol-water ternary solvent system (MEW system) on the skin permeation of morphine hydrochloride (MPH) was investigated in hairless rats. The cumulative amount of MPH permeated through the excised abdominal skin over 8 h (Q-8) was selected as an index of skin permeability. With changing MPH concentration over a wide range from 0.01 to 10% in a MEW system (5% l-menthol and 40% ethanol), the values of Q-8 were proportional to MPH concentration. The concentration was fixed at 1% for the following experiments. For the effect of the concentration of l-menthol at 40% ethanol, the maximum Q-8 was observed at 5% l-menthol, and no greater enhancement of Q-8 was obtained by increasing l-menthol concentration above that. In the ethanol effect at 5% l-menthol, the maximum Q-8 was observed at 45% ethanol. When 2-propanol and methanol, which are more lipophilic and hydrophilic than ethanol, respectively, were used instead of ethanol, the maximum values of Q-8 were observed at 40 and 55%. The maximum values for Q-8 were obtained in the vicinity of the solubility of l-menthol in the MEW system in all cases, suggesting that the skin permeation enhancing effect of the system is dependent on the thermodynamic activity of l-menthol.

1-Propanol↗
PubMed1993

Clinical and laboratory studies of severe periodontal disease in an adolescent associated with hypophosphatasia. A case report.

Hypophosphatasia is a congenital disease characterized by defective bone mineralization, deficiency of alkaline phosphatase (ALP) activity, increased excretion of the phosphoethanolamine (PEA) in the urine, and premature loss of the deciduous teeth. A male hypophosphatasia patient (aged 15 years 6 months) with premature exfoliation of the deciduous teeth was referred to our hospital because of severe periodontal destruction in the permanent dentition. Blood and urine tests as well as oral and periodontal examinations were performed. Serum antibody titers against 7 periodontopathic bacteria by the enzyme-linked immunosorbent assay (ELISA), monocyte and neutrophil chemotaxis measurements, and cellular immunity tests were also performed. Low levels of ALP in serum and PEA in the urine were found. Monocyte and neutrophil chemotaxis exhibited normal values. Slightly depressed CD2+, CD3+, and CD4+ and slightly elevated activity of NK cells were found. An elevated level of serum antibody to Porphyromonas gingivalis was observed. Oral radiographic examination showed a mirror pattern of alveolar bone loss which is similar to that seen in localized juvenile periodontitis. Periodontal treatment of this patient was carried out for 4 years. The severely affected sites, the lower right and left first molars and the upper right first molar, had to be extracted. However, the other sites were well maintained. The serum IgG level against P. gingivalis was decreased after 4 years of periodontal treatment. Infection with P. gingivalis was suspected to be associated with the destruction of this patient's hypophosphatasia, but other dental abnormalities such as abnormal enamel, dentin, and cementum formation may also have contributed to the periodontal pathology.

Adolescent↗
PubMed1993

Hormonal disregulation mechanism in the rat thyroid tumor induced by diniconazole.

To assess the toxicological significance of thyroidal tumor observed slightly in a long-term rat study with diniconazole, (E)-1-(2,4-dichlorophenyl)- 4,4-dimethyl-2-(1,2,4-triazol-1-yl)-1-penten-3-ol, a 3-month subacute feeding study was conducted in male Crj: CD (SD) rats by administering diniconazole in diet at concentrations of 0, 100, 1,000, or 2,000 ppm. Examinations mainly for thyroid functions were performed at Weeks 2, 4 and 13. Measurement of serum hormone levels revealed continuous decreases in serum thyroxine (T4) and free T4 levels at and above 1,000 ppm and increase in serum thyroid stimulating hormone (TSH) level at 2,000 ppm concurrently with liver weight and hepatic UDP-glucuronyltransferase (UDP-GT) increases at and above 1,000 ppm. No changes were observed in serum triiodothyronine (T3) and free T3 levels. Increase in thyroid uptake of 125I and organification of 125I in the thyroid at 2,000 ppm and thyroid follicular cell hyperplasia at and above 1,000 ppm were also observed. However, no compound-related changes were observed in autopsy and organ weight in the thyroid. Based on the above results, diniconazole induces increases in the hepatic UDP-GT activity and the thyroid hormone excretion from the liver. The increased excretion of thyroid hormones causes decrease in serum T4 and free T4 levels, triggering the feedback mechanism of the pituitary gland, promotion of TSH release from the pituitary gland and increase in serum TSH level. The increased serum TSH level probably leads to increased 125I uptake of thyroid and thyroid follicular cell hyperplasia. Thus, the thyroid tumorigenesis in rats treated with diniconazole is due to the secondary overstimulant effect on the thyroid by increased serum TSH level. The toxicological significance in humans is extremely low and it is unlikely that diniconazole would increase thyroid tumor in humans even if diniconazole were to alter normal thyroid hormone level in humans.

Animals↗
PubMed1993

Highly polysialylated neural cell adhesion molecule (NCAM-H) is expressed by newly generated granule cells in the dentate gyrus of the adult rat.

We have found in the adult rat that the persistent expression of a highly polysialylated neural cell adhesion molecule (NCAM-H) that is generally specific to developing tissues, remains restrictively in the cells of the deepest portion of the dentate granular layer. Since the granule cells are known to continue to be generated in this region during the adult period, we have tried to determine whether NCAM-H is expressed by newly generated granule cells. Immunoelectron microscopic observation revealed that about half of the NCAM-H-expressing cells had the features of dentate granule cells, and that the rest of these cells appeared to be immature cells. Double immunostaining for NCAM-H and glial fibrillary acidic protein (GFAP) revealed that the NCAM-H-expressing cells differed from GFAP-positive glial cells. In rats injected with 5-bromo-2'-deoxyuridine (BrdU) at post-natal day 35, double immunostaining for NCAM-H and BrdU demonstrated that the BrdU-labeled cells expressed NCAM-H at 12 d after the injection but not at 80 d. These results provide the first direct evidence that NCAM-H is expressed transiently by newly generated granule cells that may add new neuronal circuits to the adult hippocampal formation.

Animals↗
PubMed1993

[Molecular biological analysis of HLA class II gene in autoimmune hepatitis among Japanese].

The frequencies of HLA B54, DR4, DR53 and DQ4 were significantly higher in patients with autoimmune hepatitis than in healthy controls. HLA-DR4 was most frequently associated with autoimmune hepatitis. To define the HLA class II gene which has the susceptibility or resistance to autoimmune hepatitis, we performed HLA class II genotyping using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) method. The frequency of DRB1*0405 was significantly higher in autoimmune hepatitis than in controls. However, there was no significant difference in the frequency of the DR4 associated Dw-allele between the patients and the controls who were DR4-positive. Six DR4-negative patients had DR2, but there was no significant difference in the frequency of the DR2-associated Dw-alleles compared with the DR2-positive controls. Comparison of the amino acid residues of DRB1 chain suggested that the basic amino acid at position 13, which is present only on the DR2 and DR4 B1 molecules (Arg on DR2 and His on DR4), contributes to the susceptibility to autoimmune hepatitis among Japanese.

Asian People↗
PubMed1993

Association of primary biliary cirrhosis with human leukocyte antigen DPB1*0501 in Japanese patients.

To investigate the relationship between distribution of human leukocyte antigen alleles and susceptibility to primary biliary cirrhosis among Japanese, we performed serological typing and human leukocyte antigen DP genotyping in 47 Japanese patients with primary biliary cirrhosis. Serologically, the frequency of human leukocyte antigen DQ3 was significantly higher in the patients than in healthy controls, whereas frequency of DR52 was significantly lower in the patients. Human leukocyte antigen DP genotyping using the polymerase chain reaction-restriction-fragment-length polymorphism method showed that the frequency of human leukocyte antigen DPB1*0501 (85.1%) was significantly higher in patients than in healthy controls but that the frequency of DPB1*0402 was significantly lower in patients. The positive association of human leukocyte antigen DPB1*0501 with primary biliary cirrhosis was stronger than that of serological human leukocyte antigen DQ3, which can be explained by its linkage to DPB1*0501. In addition, three of seven DPB1*0501-negative patients had DPB1*0202, suggesting that the human leukocyte antigen DPB1 amino-acid chain plays an important role in the immunogenesis of primary biliary cirrhosis among Japanese patients. Comparative analysis of amino acid sequences from DPB1 alleles indicated that a Leu at position 35 of the DPB1 chain likely contributes to the susceptibility to primary biliary cirrhosis among the Japanese.

Adult↗
PubMed1993

[Cardiac function following left ventricular aneurysm repair--comparison between patch reconstruction and direct closure methods].

Left ventricular function was compared between two groups of patients who underwent patch reconstruction or direct closure of the ventricular wall following resection of a post-infarction left ventricular aneurysm (LVA). There were 15 and 9 patients in the respective groups. Coronary artery bypass grafting was additionally performed in 8 patients (53%) in the patch reconstruction group and 5 patients (56%) in the direct closure group. The size of the patch used for patch reconstruction (including the suture line) was 57 +/- 19% of the resected area. Before and 1-2 months after surgery, equilibrium RI angiography and cardiac catheterization were performed to assess the following hemodynamic parameters: ejection fraction (EF) at rest and during exercise, left ventricular end-diastolic pressure (LVEDP), left ventricular end-diastolic volume index (LVEDVI), cardiac index (CI) and mean pulmonary artery pressure (m-PAP). Preoperatively, there were no differences in each parameter between the two groups. Postoperatively, there were significant improvements in the EF at rest and during exercise (p < 0.01), LVEDVI (p < 0.01) and the LVEDP (p < 0.05). However there no significant changes in CI or m-PAP following the operation. There were also no significant differences observed in the postoperative values between the two groups. However, based upon postoperative left ventriculograms, patch reconstruction was significantly superior to direct closure for reconstruction of a septal aneurysm.

Aged↗
PubMed1993

[Vanishing tumor thrombus in IVC after oral administration of UFT and TAE in a patient with HCC; a case report].

A 74-year-old man was diagnosed as hepatocellular carcinoma (HCC) in the area of S6-7 with tumor thrombus continuously developed from hepatic vein to inferior vena cava (IVC). AFP value remained high despite two transcatheter arterial embolizations with adriamycin, mitomycin and Lipiodol (Lp-TAE). The AFP value gradually decreased two weeks after oral administration of UFT. Nine months after, the AFP level was 26.4 ng/ml and the tumor thrombus in the IVC disappeared. The size of the main tumor did not change. This case suggests Lp-TAE and UFT are useful for suppressing the growth of the main tumor and to extinguish the tumor thrombus.

Aged↗
PubMed1993

Augmented production of interleukin-8 in cerebrospinal fluid in bacterial meningitis.

Interleukin-8 (IL-8) elaborated by monocytes and endothelial cells is a cytokine which is responsible for adhesion of leucocytes to vascular endothelium and migration of neutrophils into the cerebrospinal fluid (CSF) from the intravascular space. The inflammation in meningitis is elicited by the cytokine release from leucocytes which encounter micro-organisms in the arachnoid or subarachnoid space. In bacterial meningitis, tumour necrosis factor (TNF), IL-1 and IL-6 are produced vigorously, and initiate and augment the inflammation in the central nervous system. In this study, utilizing a quantitative immunometric sandwich enzyme immunoassay, the concentration of IL-8 was investigated in the CSF of patients with bacterial meningitis, patients with aseptic meningitis, and patients with gastroenteritis who served as controls. The IL-8 concentration was markedly higher in the CSF of patients with bacterial meningitis (224 +/- 2.57 pg/ml; mean +/- SD) than in the CSF of patients with aseptic meningitis (less than 30 pg/ml). The IL-8 level in the CSF of patients with aseptic meningitis did not differ from that in the CSF of the patients with gastroenteritis (less than 30 pg/ml). The augmented production of IL-8 in CSF may account for the inflammation in bacterial meningitis being more severe than that in aseptic meningitis.

Acute Disease↗
PubMed1993

[Cell viability assessment of cold-preserved (4 degrees C) and cryopreserved (-196 degrees C) allograft valves by flowcytometric analysis].

We introduced cryopreservation technique to store the allograft valve and subsequently commenced the use of the cryopreserved aortic allograft valve for aortic valve replacement. For the clinical use of the allograft valve, it is essential to evaluate the cell viability. We assessed cell viability of the allograft valve by flowcytometry (FCM), using a fluorescein diacetate (FDA)-propidium iodide (PI) stain. Pulmonary allograft valves were harvested from the cadavers with a consent. Of the 9 valves collected and sterilized in 4 degrees C antibiotic solution for 48 hours, 4 valves were stored under refrigeration (cold-preserved), and the remaining 5 valves were cryopreserved. The warm ischemic time from cardiac death to valve preservation was 7.3 +/- 5.4 hours. The cold-preserved valves were stored at 4 degrees C in the nutrient medium (TC-199, calf serum and HEPES buffer). The cryopreserved valves were frozen by a programmable freezer to -80 degrees C in the same nutrient medium containing 10% dimethylsulfoxide (DMSO), and subsequently stored in liquid nitrogen (-196 degrees C). We assessed the cell viability of the allograft valve leaflet, before storage and at 2 weeks, 1 month and 2 months after the storage. Suspensions of the valve leaflet fibroblasts were double-stained with FDA (1 micrograms/ml) and PI (1 microgram/ml) for flowcytometric analysis of the viable cells (cells showing a chromatic response to FDA but no response to PI). In the cold-preserved group, percentage of the viable cell was 90.3 +/- 3.6% before storage, 62.0 +/- 3.0% after 1 month of storage, and 50.3 +/- 3.7% after 2 months of storage.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve↗
PubMed1993

[Transcatheter arterial chemoembolization to hepatic metastases from colorectal cancer].

Response of transcatheter arterial chemoembolization (TAE) and transcatheter arterial infusion chemotherapy to hepatic metastases was reported in 25 cases of colorectal cancer. The severity of liver metastases was H1 in 12 cases, H2 in 9 cases, and H3 in 4 cases. Liver metastases were found during surgery in 12 of these patients, and 13 showed metastases or recurrence in the liver after resections of primary lesions. Catheters were inserted selectively to the proper hepatic artery by Seldinger's method, followed by injection of embolizing agents (gelfoam particles of Lipiodol) with adriamycin or 5-FU + leucovorin in most cases. Response was assessed by blood CEA levels, diagnostic imaging, and period of survival. In 5 cases in whom liver resections were performed following TAE, response was assessed by histopathological findings of the resected specimens. Two patients showed partial response (PR), 12 no change (NC) and 11 progressive disease (PD) by diagnostic imaging. Blood CEA levels fell to less than 50% of pre-treatment levels in 26% of cases. Histological changes by TAE were confirmed in 4 of 5 cases after liver resections, but viable cancer cells were observed in all cases. A case of mucinous cancer showed no change histologically. As the other case of mucinous cancer showed PD by diagnostic imaging, TAE was not suggested to be suitable to treat cases of mucinous cancer. More improvements in the dosage, drugs and times of treatment were suggested to yield a better response rate in TAE therapy for liver metastases from colorectal cancer.

Adult↗
PubMed1993

Depression of drug-metabolizing activity in the human liver by interferon-beta.

The depressant effect of interferon beta on drug-metabolizing activity in the human liver was investigated. Seven patients with chronic hepatitis C were treated with interferon beta at doses of 3 x 10(6) to 9 x 10(6) IU/day for 8 wk. The activities of 7-methoxycoumarin O-demethylase and 7-ethoxycoumarin O-deethylase in specimens obtained by liver biopsy were examined before and after interferon treatment. Theophylline pharmacokinetics were also examined before and after interferon treatment. Interferon beta treatment reduced the activities of both O-dealkylases from 6.0 (100%) to 3.2 (53%) nmol/gm liver per minute and from 1.9 (100%) to 1.1 (58%) nmol/gm liver per minute, respectively (p < 0.05). The total body clearance of theophylline was also decreased (from 0.76 to 0.56 ml/kg/min; p < 0.05), and its elimination half-life was increased (from 8.4 to 11.7 hr; p < 0.05); however, the volume of distribution was not significantly affected. The magnitude of the decreases in enzyme activities and in theophylline clearance varied widely in individual patients and did not correlate with the dose of interferon administered. This study provides the first direct evidence that interferon beta can depress the activity of drug-metabolizing enzymes in the human liver.

7-Alkoxycoumarin O-Dealkylase↗
PubMed1993

[Late results of aortic valve plasty (aortic leaflet slicing) simultaneously performed with mitral valve surgery].

We followed the course of 20 patients who underwent aortic valve plasty (AVP) combined with mitral valve surgery for rheumatic mild aortic valve disease in association with severe mitral valve disease. At operation, all patients underwent aortic leaflet slicing with a knife, and aortic commissurotomy were performed additionally in 10 patients. After surgery, the degree of aortic valve regurgitation and the amplitude of aortic leaflet motion were assessed chronologically, using ultrasound cardiography. One month after surgery, all but one patients showed a reduction in regurgitation to degree I or less. From the third post-operative year, however aortic valve regurgitation tended to increase again. However, the post-operative degree of regurgitation was observed not to be severer than the pre-operative degree of regurgitation, and no patients showed aggravation of aortic valve regurgitation attributable to exacerbation of mitral valve disease. We divided the patients into two groups according to improvement of aortic valve regurgitation. In the group where the degree of regurgitation returned to the pre-operative one, the degree of amplitude of leaflet motion began to reduce from the third post-operative year and was nearly equal to the pre-operative one at the fifth post-operative year. The results of this study can be summarized as follows: 1. From the third post-operative year, aortic regurgitation was aggravated and aortic valve motion amplitude decreased. 2. The number of sliced valve leaflets and incised commissures did not correlate well with the post-operative reduction in regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Percutaneous transluminal angioplasty of dialysis access shunts].

Sixteen balloon angioplasties were performed in 10 patients with upper-extremity dialysis access shunts. The initial success rate was 80% (12/15). Of the initial successes, 58% (7/12) were patent at six months and 13% (1/8) at one year. In nine cases, repeat PTA was necessary. The mean interval of patency was about four months. The longest interval was two and a half years. The complication of thrombosis of the loop shunt during PTA was successfully treated by fibrinolytic therapy.

Adult↗