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Biomedical subjects

H Tsuji

Publications and source records attributed to H Tsuji.

At least 55 records · Page 3Linked to original sources
PubMed2001

Effect of cicletanine on the nitric oxide pathway in human umbilical vein endothelial cells.

The purpose of this study was to evaluate the effects of cicletanine, a slightly diuretic antihypertensive drug, on human vascular endothelial cells with regard to nitric oxide, intracellular calcium concentration ([Ca2+]i), cyclic nucleotide, inositol 1,4,5-trisphosphate (IP3), and prostacyclin generation. Primary cultured human umbilical vein endothelial cells were used in this study. [Ca2+]i was measured by fura-2/AM. Cyclic adenosine monophosphate (AMP), cyclic guanosine monophosphate (GMP), IP3, and prostacyclin were measured by radioimmunoassay. Nitric oxide was measured by the Griess method. Cicletanine had no effect on [Ca2+]i. Cicletanine (10(-6)-10(-4) M) increased cyclic GMP but decreased prostacyclin generation. Cicletanine had no stimulating effect on cyclic AMP or IP3 generation. IP3 increased 45Ca release from storage sites. Cicletanine decreased prostacyclin generation via increase in cyclic GMP. Cicletanine had no stimulating effect on nitrogen oxides for 2 h after incubation but increased it after 3-24 h. Pretreatment with L-N(G)-monomethyl-arginine (L-NMMA) prevented this increase. The inhibitory effect of L-NMMA was prevented by pretreatment with L-arginine. These results indicate that nitric oxide and cyclic GMP may contribute to the antihypertensive action of cicletanine.

Antihypertensive Agents↗
PubMed2001

[Isolation and incidence of Cryptosporidium and Giardia from river water].

A study was conducted during the period from July to October in 1999, surface water samples were collected from 13 rivers in Hyogo Prefecture serving as tap water sources and examined for Cryptosporidium oocysts and Giardia cysts using the immunomagnetic separation method. In 9 (69%) of the 13 rivers, Cryptosporidium oocyst was detected. Giardia cyst was detected in 5 (38%) of the 13 rivers. The Cryptosporidium oocyst positive rate was comparable to that of fecal bacteriological indicators, which was also examined and detected in 10 (77%) of 13 rivers. Water samples were collected at 69 points in the 13 rivers. Cryptosporidium parvum oocyst was detected at 38 (55%) of the 69 points, demonstrating widely spread contamination. Comparing 3 areas which were divided on the basis of agricultural circumstance as well as geographical locating, the Cryptosporidium positive rate varied widely according to the area, ranging from 37% to 100%. To elucidate the reason for these differences, the relationship between positive rate and the species and number of livestock animals raised in each respective region was investigated. The results showed a strong correlation (r = 0.91) between the number of raised cattle and contamination with the rate of Cryptosporidium in each area. Furthermore, genetic analysis by PCR-restriction fragment length polymophism method revealed that C. parvum oocyst detected in the rivers studied was the bovine type, probably indicating that the oocyst was excreted from the cattle in the river basins. The degree of contamination with Cryptosporidium in river water was comparable to that of fecal bacteriological indicators, suggesting the possibility that fecal bacteriological indicators examination might be used as a criterion of Cryptosporidium contamination.

Animals↗
PubMed2001

Contamination of river water by Cryptosporidium parvum oocysts in western Japan.

In Japan, only a few rivers have been inspected for Cryptosporidium parvum contamination, and the methods used had low sensitivity. In 1998 and 1999, we used a method with higher sensitivity to examine all large rivers used as sources of water supply in one prefecture (which we divided into four areas) in western Japan for Cryptosporidium oocysts. One sample was collected at each of 156 sites along 18 rivers, and samples were tested for Cryptosporidium oocysts by immunomagnetic separation. Samples were classified as being obtained on an island with livestock and fishing industries, a densely populated urban area, a western region including farming villages, or a still more rural northern area with agriculture and fishing. Restriction fragment length polymorphism analysis was used for identification of the C. parvum found as the bovine or human type. C. parvum was detected in at least one sample from 13 of the 18 rivers and in 47% (74 of 156) of the samples. One-third to all of the samples from each area contained C. parvum oocysts. The number of C. parvum oocysts per 20 liters of river water varied in the same pattern as the number of cattle kept in the four kinds of areas (as determined by the Mantel extension test). Oocysts isolated were of the bovine type; the C. parvum detected in rivers probably came from cattle kept in that valley. As we had expected, when tested with a more sensitive method, river water in western Japan was found to be greatly contaminated with C. parvum oocysts, as reported in other countries.

Animals↗
PubMed2001

Adrenomedullin inhibits angiotensin II-induced expression of tissue factor and plasminogen activator inhibitor-1 in cultured rat aortic endothelial cells.

Adrenomedullin (AM) is a potent vasodilating peptide having a variety of pharmacological properties mainly in respect to vascular pathophysiology. We have previously demonstrated that angiotensin II (Ang II) or natriuretic peptides have influence on the expression of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1) in vascular endothelial cells. The aim of this study was to elucidate the effects of AM on TF and PAI-1 mRNA and protein expression in endothelial cells. As a result, AM inhibited Ang II-induced TF and PAI-1 mRNA expression in a dose- and time-dependent manner. Because the expression of TF and PAI-1 mRNA induced by Ang II was attenuated by the increase of intracellular concentrations of cAMP by forskolin and 8-bromo-cAMP and because AM increased the intracellular level of cAMP in rat aortic endothelial cells, it was indicated that the inhibitory effect of AM on the expressions of TF and PAI-1 was mainly mediated by the cAMP-dependent signal transduction. Furthermore, the inhibitory effect of AM on TF and PAI-1 expression was partly attenuated by an NO synthase inhibitor, N(G)-nitro-L-arginine methyl ester. In conclusion, AM is shown to contribute to the regulation of blood coagulation and fibrinolysis by vascular endothelial cells mainly via the cAMP pathway.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed2001

Tissue distribution of a major mevalonate pyrophosphate decarboxylase in rats.

The 45- and 35-kDa subunits of mevalonate pyrophosphate decarboxylase (MPD) have been purified from rat liver. In this study, we examined the relationship between 45- and 35-kDa MPD and the tissue distribution of a major MPD in rat liver. When the crude extract of rat liver fed on normal chow was subjected to immunoblot analysis using anti-rat 45-kDa MPD antibody, only the 45-kDa band was detected. In a pulse-chase experiment using anti-rat 45-kDa MPD antibody, there was no precursor-product relationship between the 45- and the 35-kDa MPD. In immunoprecipitation, more than 85% of MPD activity in the rat liver was depleted from the crude extract with an excess of the above antibody. When 45-kDa MPD contents in tissues were analyzed by immunoblotting, a single protein band with an apparent molecular weight of 45 kDa was detected in all tissues. The specific protein content of 45-kDa MPD in liver was markedly higher than in other tissues. The activity/amount ratio varied among brain, liver, and testis, being significantly highest in the liver. From these data, it is suggested that 45-kDa MPD serves as a major enzyme involved in cholesterol biosynthesis in rat liver and that a tissue-specific regulator or isozyme of 45-kDa MPD is present in rat liver.

Animals↗
PubMed2001

Mevalonate pyrophosphate decarboxylase is predominantly located in the cytosol of rat hepatocytes.

Mevalonate pyrophosphate decarboxylase (MPD) is found in the 100000 x g supernatant fraction of cells or tissues and is considered to be a cytosolic protein. Recently, other groups reported that MPD is mostly located in the peroxisomes. In this study, we used two different methods to determine whether MPD is predominantly located in the peroxisomes or the cytosol of rat hepatocytes. 1) In permeabilized rat hepatocytes or normal rat kidney cells treated with digitonin, which lack cytosolic enzyme, MPD was mainly present in the medium. 2) Double immunofluorescent labeling of cells with both anti-MPD antibody and anti-hexokinase antibody yielded an immunofluorescent pattern for both enzymes typical of the cytosolic protein. These results indicate that MPD is predominantly located in the cytosol of rat hepatocytes.

Animals↗
PubMed2001

Difference in subcellular distribution between 45- and 37-kDa mevalonate pyrophosphate decarboxylase in rat liver.

We previously reported that the CP diet (a diet containing 5% cholestyramine and 0.1% pravastatin)-induced new species of 37-kDa mevalonate pyrophosphate decarboxylase (MPD) was characteristically and immunologically very similar to the well-known 45-kDa MPD. In the present study, we found a difference in subcellular distribution between 45- and 37-kDa MPD by cell fractionation and immunoblot analysis. The cytosol fraction contained 45- and 37-kDa MPD. Peroxisomal fraction contained a small amount of 45-kDa MPD, but not 37-kDa MPD. Also, 45-kDa MPD in peroxisome is localized in the matrix. From these data, the difference in subcellular distribution between 45- and 37-kDa MPD may be due to differences in the physiological role of cholesterol biosynthesis in rat liver.

Animals↗
PubMed2001

Mevalonate pyrophosphate decarboxylase in stroke-prone spontaneously hypertensive rat is reduced from the age of two weeks.

We carried out a comparison of tissue distribution of mevalonate pyrophosphate decarboxylase (MPD) between normotensive Wistar Kyoto rat (WKY) and stroke-prone spontaneously hypertensive rat (SHRSP) using Western blotting. However, there was no difference in tissue distribution of MPD between WKY and SHRSP, expect in brain and liver. We then compared the MPD between WKY and SHRSP liver at several weeks of age. We found that MPD in the liver as well as brain of SHRSP was significantly reduced from two weeks of age. This data is useful to identify or understand the mechanism underlying the reduced amount of MPD in SHRSP.

Aging↗
PubMed2001

Initial symptoms of acute radiation syndrome in the JCO criticality accident in Tokai-mura.

A criticality accident occurred on September 30, 1999, at the uranium conversion plant in Tokai-mura (Tokai-village), Ibaraki Prefecture, Japan. When the criticality occurred, three workers saw a "blue-white glow," and a radiation monitor alarm was sounded. They were severely exposed to neutron and gamma-ray irradiation, and subsequently developed acute radiation syndrome (ARS). One worker reported vomiting within minutes and loss of consciousness for 10-20 seconds. This worker also had diarrhea an hour after the exposure. The other worker started to vomit almost an hour after the exposure. The three workers, including their supervisor, who had no symptoms at the time, were brought to the National Mito Hospital by ambulance. Because of the detection of gamma-rays from their body surface by preliminary surveys and decreased numbers of lymphocytes in peripheral blood, they were transferred to the National Institute of Radiological Sciences (NIRS), which has been designated as a hospital responsible for radiation emergencies. Dose estimations for the three workers were performed by prodromal symptoms, serial changes of lymphocyte numbers, chromosomal analysis, and 24Na activity. The results obtained from these methods were fairly consistent. Most of the data, such as the dose rate of radiation, its distribution, and the quality needed to evaluate the average dose, were not available when the decision for hematopoitic stem cell transplantation had to be made. Therefore, prodromal symptoms may be important in making decisions for therapeutic strategies, such as stem-cell transplantation in heavily exposed victims.

Amylases↗
PubMed2001

Sandwich enzyme-linked immunosorbent assay system for micro-detection of the wheat allergen, Tri a Bd 17 K.

Seven monoclonal antibodies (mAbs) against the wheat allergen, Tri a Bd 17 K, were prepared to obtain mAbs suitable for a sandwich enzyme-linked immunosorbent assay (sandwich ELISA) for determination of the allergen. Two of the mAbs strongly immunoblotted the allergen purified from wheat flour. However, only one (1G11) of them was found to be suitable for sandwich ELISA. Epitope mapping against mAb-1G11 on the allergen showed that the mAb recognized the peptide containing Lys-38 and Gln-39 of the allergen. We developed a sandwich ELISA method consisting of Aleuria aurantia lectin for fixing the allergen and 1G11 as the first antibody that enabled 4-4,000 ng/well of the allergen to be determined.

Allergens↗
PubMed2001

Cold activation of serum complement in patients with chronic hepatitis C: study on activating pathway and involvement of IgG.

It has been documented that the serum complement activities measured by hemolytic assay (CH50) are decreased after storage of sera at a low temperature in some patients with chronic hepatitis C. However, the mechanism of this phenomenon has not been identified yet. Here, we tried to elucidate factors involved in the cold activation of complement (CAC). To clarify what pathway is activated in CAC, we measured complement cleavage products after cold storage of sera. C4d increased significantly after 12 h-storage at cold temperatures in 5 CAC (+) sera compared with 5 CAC (-) (P < 0.01) and 3 control sera (P < 0.05), while Bb did not increase in any of the groups. In order to determine whether IgG or IgG complex is necessary for CAC, 8 CAC (+) sera were incubated with Protein G Sepharose gel beads, and all of them retained hemolytic activities to some extent after cold storage. Column chromatography through Superose 6HR of CAC-positive serum identified the fractions containing molecules that induced CAC in normal serum, which were depleted by treatment with protein G Sepharose. In conclusion, CAC in hepatitis C seems to occur via a classical or lectin pathway, and the IgG complex produced in hepatitis C virus infection may be an important factor in inducing CAC, a common extrahepatic manifestation of hepatitis C.

Adult↗
PubMed2001

Progression of ossification of the posterior longitudinal ligament following en bloc cervical laminoplasty.

BACKGROUND: Ossification of the posterior longitudinal ligament often causes compressive myelopathy. Ossification is a progressive disease, and it has been reported that the area of ossification increases after decompressive surgery. However, it is uncertain how the progression of ossification affects the long-term outcome after cervical laminoplasty. This study was performed to clarify the relationship between the progression of ossification of the posterior longitudinal ligament and the clinical results following en bloc cervical laminoplasty. METHODS: Forty-five patients who were followed for more than ten years after laminoplasty participated in this study. Radiographs and tomograms of the cervical spine of each patient were made before and after the operation and at the time of the latest follow-up. The extent of ossification in the longitudinal and sagittal axes was evaluated. Neurological function was graded with use of the Japanese Orthopaedic Association scoring system. The relationship between the progression of ossification and the score-based rate of recovery was analyzed. RESULTS: Thirty-three (73%) of the patients had progression of ossification of the posterior longitudinal ligament after laminoplasty. Progression was frequent in patients with the mixed type of ossification and in those with the continuous type, whereas it was rare in patients with the segmental type. The patients with progression of the ossification were significantly younger than those without progression (p = 0.018). The Japanese Orthopaedic Association score improved rapidly within one year and continued to improve up to five years after surgery. The score tended to decrease thereafter. For thirteen patients, the score had worsened at the time of the latest follow-up. Three patients had neurological deterioration following an increase in the thickness of the ossification. CONCLUSIONS: Progression of ossification of the posterior longitudinal ligament was often observed during the long-term follow-up period after laminoplasty. Young patients with mixed and continuous types of ossification had the greatest risk for progression. Preventive measures, such as the use of a wider laminar opening during the laminoplasty, should be considered for patients who are at risk for progression of ossification.

Adult↗
PubMed2001

Lower mortality in patients with the DD genotype of the angiotensin-converting enzyme gene after acute myocardial infarction.

OBJECTIVE: The angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism has been associated with different serum ACE concentrations and cardiac ACE activity. We assessed whether the ACE gene I/D polymorphism influenced cardiac mortality in Japanese patients with acute myocardial infarction. METHODS AND RESULTS: The ACE gene I/D polymorphism was determined in 441 consecutive patients with a first myocardial infarction. There were 69 patients (16%) with the DD genotype, 194 patients (44%) with the ID genotype, and 178 patients (40%) with the II genotype. During a mean follow-up of 9.4 months, there were 49 cardiac deaths (DD, n = 4; ID, n = 26; II, n = 19). The DD genotype was significantly associated with a lower mortality than the other genotypes (p = 0.0363) by Cox regression analysis adjusted for age, sex, site of myocardial infarction, Killip functional class, reperfusion therapy during acute phase, ACE inhibitor use, and beta-blocker use. CONCLUSIONS: In a selected cohort of Japanese patients, the DD genotype was associated with a significantly lower cardiac mortality after a first myocardial infarction.

Female↗
PubMed2001

Effect of dietary seal and fish oils on lipid metabolism in hamsters.

Eicosapentaenoic and docosahexaenoic acids were distributed mainly in the sn-1 and 3 positions of seal oil triacylglycerols and in the sn-2 position of fish oil triacylglycerols. Seal oil-rich or fish oil-rich fats having constant polyunsaturated (PUFAs)/monounsaturated/saturated fatty acids and n-6/n-3 PUFAs ratios were fed to hamsters for 3 weeks. The control fat contained linoleic acid as the sole PUFA. The concentration of triacylglycerols in the liver was significantly lower in the fish oil group than in the control group. Phospholipid concentration in serum was lower and that in the liver was higher in the seal oil group compared with the fish oil group. The activities of fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase (G6PDH), and the malic enzyme were significantly lower in both the fish and seal oil groups than in the control group. Dietary seal oil more effectively reduced arachidonic acid content in liver phosphatidylcholine and phosphatidylethanolamine and serum phosphatidylcholine than fish oil. These results showed that different intramolecular distribution of n-3 PUFAs influenced glycerolipid metabolism and arachidonic acid content in serum and liver phospholipids of hamsters.

Animals↗
PubMed2001

[A case of renal oncocytoma with synchronous contralateral renal cell carcinoma].

A case of bilateral, synchronous renal cell carcinoma and oncocytoma is reported. The patient was a 70-year-old woman. Computed tomographic scan revealed bilateral low density masses, which had a diameter of approximately 4 cm (right kidney), and 2.5 cm (left kidney). We suspected bilateral renal cell carcinomas, and performed, right nephrectomy and left enucleation of the tumor. Pathological diagnosis was right renal cell carcinoma and left oncocytoma. To our knowledge only 5 previous cases of renal cell carcinoma associated with oncocytoma have been reported in Japan. Two cases were metachronous and three cases were unilateral and synchronous. This is the first reported case of bilateral, synchronous renal cell carcinoma and oncocytoma.

Adenoma, Oxyphilic↗
PubMed2001

[Mitogen-induced lymphocyte transformation in patients with Yusho].

To evaluate chronic immune effects of polychlorinated biphenyl (PCB), in vitro lymphocyte transformation in response to nonspecific mitogens were studied in 74 patients with Yusho in 2000. Elevated response in phytohemagglutinin (PHA)-induced lymphocyte transformation was detected in fifteen (20.3%) patients, while decreased PHA response was found in six (8.1%) patients. Concanavalin A (Con A)-induced lymphocyte transformation was increased in six (8.1%) patients, and decreased in eleven (14.9%) patients. There were no significant correlations between blood PCB concentrations and lymphocyte transformation in response to PHA, Con A, or pokeweed mitogen (PWM). We conclude that abnormality of lymphocyte transformation in patients with Yusho is frequent, but it may not be associated with blood PCB concentration.

Adult↗
PubMed2001

[A case of pneumonia, septic pulmonary embolisms with cavities, bilateral large lung abscesses, and multiple liver abscesses caused by Klebsiella pneumoniae].

A 64-year-old man suffering from diabetic hyperosmolar non-ketotic coma was admitted for acute lung abscess in the left apical lung field. Sputum culture and blood culture showed a heavy growth of Klebsiella pneumoniae (K. pneumoniae). He was suffering from sepsis, septic pulmonary embolisms with cavities, bilateral pulmonary consolidations, and multiple liver abscesses. Gradually, the bilateral lung consolidations resolved and areas of consolidation were noted to undergo extensive cavitation bilaterally. Cavitation and abscess formation are frequent complications of K. pneumoniae. Generally, large bilateral lung abscesses caused by K. pneumoniae have a poor prognosis. Cavity nodules are often present in septic pulmonary embolisms. We report a very rare case in a patient with three types of cavities with differing mechanisms. The first was an acute lung abscess, the second, septic pulmonary embolisms with cavities, and the third, large bilateral lung cavities noted in the course of resolving consolidations.

Bacteremia↗