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J Hayashi

Publications and source records attributed to J Hayashi.

At least 19 recordsLinked to original sources
PubMed1995

Age-associated changes of mitochondrial translation and respiratory function in mouse brain.

We examined age-associated changes of respiratory enzyme activities and protein synthesis in mitochondria isolated from mouse brain with high oxidative activities. Cytochrome c oxidase activity increased unexpectedly with aging, while the mitochondrial translational activities showed two phases of alterations: they increased progressively up to 21 weeks after birth followed by a gradual decrease with aging. Results showed that these changes were not due to the change in mitochondrial DNA (mtDNA) copy number or the accumulation of deletion mutations in mtDNA. These observations suggest that the common feature of age-associated changes in both human and mouse mitochondrial functions is limited to the decrease in mitochondrial translational activity. Therefore, mouse brain can be used as a model to understand the relationships between aging and mitochondrial function by examining the cause of decrease in mitochondrial translation activity.

Aging↗
PubMed1995

Intrafamilial transmission of hepatitis-C virus among the population of an endemic area of Japan.

OBJECTIVES: To assess the role of intrafamilial transmission of hepatitis C virus (HCV) among general populations. DESIGN AND SETTING: Cross-sectional study in an HCV-endemic area of Japan. PARTICIPANTS: A total of 1122 residents (mean age, 41.7 years; range, 0 to 80 years), including 359 mother-child pairs and 234 pairs of spouses. MAIN OUTCOME MEASURES: Antibody to HCV (anti-HCV) was examined using second-generation anti-HCV testing by passive hemagglutination assay. Hepatitis C virus RNA was detected by polymerase chain reaction with primers deduced from the 5'-noncoding region and HCV genotypes by reaction with type-specific primers deduced from the HCV core gene. RESULTS: Prevalence of anti-HCV was 14.1% (158/1122), and HCV RNA was detected in 82.9% of those who tested positive for anti-HCV. Prevalence of anti-HCV increased with advancing age, but no anti-HCV was found among 312 persons younger than 20 years. Of the 53 children with anti-HCV-positive mothers, three were positive for anti-HCV, all were older than 20 years, and all had a history of surgical treatment. Hepatitis C virus RNA was found in one mother-child pair but with different HCV genotypes. Both spouses were positive for anti-HCV in 17 of 234 pairs. Of the 11 pairs of spouses in whom the HCV genotypes of both were determined, five had different HCV genotypes. CONCLUSIONS: While HCV is highly endemic in this area, neither vertical nor horizontal transmission between spouses seems to play an important role in its spread. The incidence of intrafamilial transmission of HCV seems to be low.

Adolescent↗
PubMed1995

Characterization of ATP receptor responsible for the activation of phospholipase A2 and stimulation of prostaglandin E2 production in thymic epithelial cells.

In TEA3A1 rat thymic epithelial cells, ATP stimulates prostaglandin E2 (PGE2) production through activation of phospholipase A2 (PLA2) enzymic activity. The stimulation of PGE2 production tested with other nucleotides indicated the agonist potency of adenosine 5'-[gamma-thio]triphosphate (ATP[S]) > or = UTP > ATP, with ED50 of about 10 microM for ATP[S]. In TEA3A1 cells, cross-linking studies with ATP[35S] revealed the presence of four cell-surface cross-linked bands of 42 kDa, 53 kDa, 83 kDa and 100 kDa in Triton X-100 extracts of TEA3A1 cells by fluorography. Guanosine 5'-[gamma-thio]triphosphate specifically blocked the cross-linking of ATP[35S] to the 53 kDa, 83 kDa and 100 kDa ATP-binding proteins, and inhibited the ATP[S]-mediated stimulation of PGE2 production with an ED50 of about 25 microM. On the other hand, 2-methylthioadenosine triphosphate (2MeSATP) blocked ATP[35S] cross-linking to the 42 kDa protein, but had no effect on ATP[S]-mediated stimulation of PGE2 production. In a variant cell line, TEAvarl, derived from TEA3A1 cells that lost their response to ATP in the activation of PLA2, the presence of 83 kDa ATP-binding protein was not detected. Results from our study suggest that ATP activates PLA2 enzymic activity in TEA3A1 cells by binding to an atypical ATP receptor that has not been described previously.

Animals↗
PubMed1995

Elimination of paternal mitochondrial DNA in intraspecific crosses during early mouse embryogenesis.

To examine whether mtDNA is uni- or biparentally transmitted in mice, we developed an assay that can detect sperm mtDNA in a single mouse embryo. In intraspecific hybrids of Mus musculus, paternal mtDNA was detected only through the early pronucleus stage, and its disappearance co-incided with loss of membrane potential in sperm-derived mitochondria. By contrast, in interspecific hybrids between M. musculus and Mus spretus, paternal mtDNA was detected throughout development from pronucleus stage to neonates. We propose that oocyte cytoplasm has a species-specific mechanism that recognizes and eliminates sperm mitochondria and mtDNA. This mechanism must recognize nuclearly encoded proteins in the sperm midpiece, and not the mtDNA or the proteins it encodes, because sperm mitochondria from the congenic strain B6.mtspr, which carries M. spretus mtDNA on background of M. musculus (B6) nuclear genes, were eliminated early by B6 oocytes as in intraspecific crosses. We conclude that cytoplasmic genomes are transmitted uniparentally in intraspecific crosses in mammals as in Chlamydomonas and that leakage of parental mtDNA is limited to interspecific crosses, which rarely occur in nature.

Animals↗
PubMed1995

Serum levels of soluble interleukin-2 receptors and effects of interferon-alpha for patients with chronic hepatitis C virus.

To characterize the role of serum soluble interleukin-2 receptor (sIL-2R) in hepatitis C virus (HCV) infection, the level of sIL-2R was measured by ELISA in 117 subjects with chronic HCV infection and in 23 healthy controls. HCV RNA was detected by polymerase chain reaction in all subjects with HCV infection. Forty-seven patients with chronic hepatitis and 10 with liver cirrhosis were treated for six months with natural interferon-alpha. The sIL-2R levels of 40 asymptomatic HCV carriers (632 +/- 340 units/ml), 47 patients with chronic hepatitis (547 +/- 204 units/ml), 10 with cirrhosis (679 +/- 239 units/ml, and 20 with hepatocellular carcinoma (1145 +/- 487 units/ml) were significantly higher than those of healthy controls (380 +/- 191 units/ml) (P < 0.05, respectively). The levels of sIL-2R increased, as did the histological activity index scores (r = 0.348, P < 0.01). The level of sIL-2R rose after the initial administration of interferon in all 57 patients. In patients whom HCV RNA was eliminated from the sera within a six-month follow-up after cessation of treatment, the level of sIL-2R reverted to basal values, but in patients in whom HCV RNA was not eliminated the value was significantly higher than that before treatment. These results suggest that monitoring serum sIL-2R in patients with chronic HCV infection treated with interferon may provide information concerning the possibility of the elimination of HCV RNA.

Carcinoma, Hepatocellular↗
PubMed1995

Relationship of genotype to level of hepatitis C viraemia determined by competitive polymerase chain reaction.

To compare the levels of hepatitis C virus (HCV) viraemia in carriers of the same genotype in various stages of chronic HCV infection, we quantified the amount of HCV RNA by competitive polymerase chain reaction and determined HCV genotype using type-specific primers. The study population included 255 patients with chronic HCV infection (asymptomatic 33, chronic hepatitis 141, liver cirrhosis 50, hepatocellular carcinoma 31). Of these 255, the prevalence of HCV RNA genotype II was 67.8%, genotype III, 17.3% and genotype IV, 14.9%; no genotype I was found. The level of HCV RNA (logarithmic transformed copy numbers per 50 microliters of serum) was significantly higher in subjects of genotype II than in those of genotypes III or IV (mean titre 5.8 +/- 1.0 vs. 5.1 +/- 1.2 and 4.8 +/- 1.1, P < 0.05, respectively). There was no significant difference in the level of HCV RNA between genotypes III and IV. Of 173 patients of genotype II, there were no significant differences between the level of HCV RNA and the stage of liver disease or in the level of HCV RNA by age. Of the 129 with genotype II with a history of blood transfusion, there was no significant difference between the level of HCV RNA of patients with and without a history of transfusion or between that of patients with a history of blood transfusion and the time elapsed since blood transfusion. The level of HCV viraemia depended on the genotype of HCV RNA and did not correlate to age or to the stage of liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Determining the acuteness and stability of deep venous thrombosis by ultrasonic tissue characterization.

PURPOSE: The intent of the study was to determine whether ultrasonic tissue characterization (UTC) could indicate acuteness and stability of deep venous thrombosis (DVT) of the lower extremities. METHODS: Thrombi presenting as filling defects on color Doppler imaging in the common or superficial femoral or popliteal veins in 50 extremities in 45 patients with DVT were studied. Acute DVT was less than 4 days duration, and chronic DVT was greater than 21 days duration. UTC analysis of parameters from the normalized power spectrum of backscattered ultrasound signals from venous filling defects was performed. This spectrum approaches a straight line, and its basic parameters, slope, and Y-intercept are related to scatterer size, concentration, and the square of the scatterer-to-medium acoustic impedances. Ten of the DVT extremities were reexamined at 1 week to assess UTC changes that would indicate thrombus instability. RESULTS: Acute DVT (19 of the 50 extremities) could be distinguished from chronic DVT, mainly on the basis of significantly higher intercept values for the acute group, which were 11.6 relative decibels (dBr) higher than those of the chronic DVT group. Discriminant linear analysis of the two parameters indicated a sensitivity of 94.7% and specificity of 90.3% in correctly diagnosing acute DVT. In a small sample of 10 extremities reexamined at 1 week, acute DVT extremities showed a mean 9.4 dBr decrease in intercept values with no significant change in slope. CONCLUSIONS: UTC distinguished clinically defined acute from chronic DVT. In a small series of extremities, UTC revealed significant instability of acute thrombi in a selected patient population.

Acute Disease↗
PubMed1995

Surgery for cavoatrial extension of malignant tumors.

Surgical management for cavoatrial involvement of malignant tumors and its outcome is reported on for 6 patients; their age ranged from 55 to 79 years and 5 were male and 1 female. The basic disease was renal cell carcinoma in 5 cases and adrenal leiomyosarcoma in 1. Intracaval tumor extension was diagnosed by computed tomography, magnet resonance imaging, digital subtraction angiography, and echocardiography. The tumor was resected together with adherant vena cava and invaded right-atrial wall, using cardiopulmonary bypass and normo- or mild-hypothermia in 5 patients. The caval defect needed to be reconstructed with a slit GORE-TEX vascular prosthesis in 3 patients. In all patients the tumor resections were successful and without major complications. All patients survived and are well from 4 to 52 months after the surgery. It is concluded that such cavoatrial extensions of malignant tumors can be safely and accurately resected with the aid of cardiopulmonary bypass, with favorable early and late outcomes in patients who have no distant metastatic lesions.

Adrenal Gland Neoplasms↗
PubMed1995

Higher expression levels of alternatively spliced pX mRNA in human T lymphotropic virus type I asymptomatic carriers positive for antibodies to p40tax protein.

cDNA of human T lymphotropic virus type I (HTLV-I) pX gene mRNA expressed in peripheral blood lymphocytes of asymptomatic carriers was sequenced. One cDNA clone contained a novel splicing acceptor site, indicating an unidentified form of pX mRNA: pX delta 17 delta 37. All 21 asymptomatic carriers expressed some level of alternatively spliced pX mRNA (pX, pX delta 17, p21rex, orfII, or pX delta 17 delta 37). pX and pX delta 17 were the dominant mRNA species among the five pX mRNAs. All pX mRNAs but orfII correlated significantly with amounts of provirus DNA (P < .05). Levels of provirus DNA and pX mRNAs were significantly higher in anti-p40tax-positive carriers than in negative ones. These observations suggest that the pX mRNAs are expressed ubiquitously, with a complex pattern of splicing, and that the presence of anti-p40tax may serve as a marker for a higher virus load and viral replication levels in asymptomatic HTLV-I carriers.

Aged↗
PubMed1995

[An autopsy of an HIV infected patient with dilated cardiomyopathy (DCM)].

A case of a HIV infected 61-year-old bisexual male with dilated cardiomyopathy (DCM) is reported. The death was originally recorded as from undetermined causes, but on autopsy, his heart showed left ventricular dilatation macroscopically, variety in size and vacuolation of cardiomyocyte, partial deciduation of cardiac muscle and diffuse perivascular fibrosis microscopically. These findings were compatible with DCM which was compounded by excessive weight loss. The further data indicated that the etiology of DCM in this case was directly related to the HIV infection.

Cardiomyopathy, Dilated↗
PubMed1995

[Evaluation of three kinds of assays for the presence of antibody to hepatitis C virus (anti-HCV) and the association of them with HCV RNA].

In order to evaluate the feasibility for the detection of antibody to hepatitis C (anti-HCV), the first generation assay (c100-3 Ab) and two second generation assays (2nd EIA and 2nd PHA) were used to test 477 individuals who visited the medical hospital or clinics in Iki Island, Nagasaki Prefecture. HCV RNA, antibody titer by 2nd PHA and four kinds of antibody to epitope of HCV by RIBA II were also surveyed to determine their association with these three assays. Prevalence of anti-HCV was 26.6% by c100-3, 38.8% by 2nd PHA and 39.6% by 2nd EIA, indications that the 2nd generation assays are much more sensitive than c100-3. Prevalence of HCV RNA was 82.1% among 190, anti-HCV positive individuals; 100% among 52 individuals with liver disease, but only 75.4% in those without liver disease. HCV antibody titer, over 2(11) was higher among those who were positive for HCV RNA than those negative for HCV RNA. Four antibodies by RIBA II were all positive and reacted strongly when they were positive for HCV RNA, but only antibody to core antigen was observed among those negative for HCV RNA, suggesting that only antibody to core antigen remains in those with past HCV infection.

Adolescent↗
PubMed1995

[Evaluation of immunochromatography assay technique for detection of antibody to hepatitis B surface antigen (HBsAg)].

A new immunochromatography assay (Dainascreen Ausab Dainabot) has been recently introduced for the detection of the presence of antibody to HBsAg. To evaluate the feasibility of using the Dainascreen Ausab, we carried out comparison tests with this method and PHA. In the test of 439 sera from HB vaccinees, inhabitants in Iki Island, Nagasaki Pref., patients with autoimmune diseases and with acute hepatitis B, 154 (31.2%) were positive by Dainascreen Ausab, 145 (29.4%) were positive by PHA and 145 (29.4%) were positive by both Dainascreen Ausab and PHA. Nine (1.8%) were positive by only Dainascreen and there were none positive by only PHA. A good correlation was observed between the titer of the antibody by this method and IMx. The anti-HBs assay by this method was able to be completed within 15 minutes and the procedure was very simple. The results indicate that the sensitivity of Dainascreen is superior to PHA and that it is easy to use.

Chromatography, Thin Layer↗
PubMed1995

[Clinical analysis of 14 patients with anti-myeloperoxidase antibody positive rapid progressive glomerulonephritic syndrome].

We investigated the clinical features and outcome of 14 patients with anti-myeloperoxidase antibody (MPO-ANCA) positive rapidly progressive glomerulonephritic syndrome. Underlying diseases included microscopic polyarteritis in 6 patients, idiopathic crescentic glomerulonephritis with lung hemorrhage in 2 patients, idiopathic glomerulonephritis in 3 patients, rapidly progressive glomerulonephritic syndrome without renal biopsy in 1 patient, crescentic glomerulonephritis associated with Sjögren syndrome and progressive systemic sclerosis in 1 patient and crescentic glomerulonephritis associated with sarcoidosis in 1 patient. Five patients were male (mean age, 59.2 years) and 9 were female (mean age, 54.0 years). On admission, most patients had anemia, leukocytophilia, and marked elevation of C-reactive protein (CRP). Average hemoglobin, white blood cell count and CRP levels on admission were 8.1 mg/dl, 11,500/mm3 and 14.7 mg/dl, respectively. Average serum creatinine was 4.0 mg/dl. All patients were treated with steroids either with or without cyclophosphamide. As the patients recovered clinically, the MPO-ANCA titers declined. Although most patients responded well to immunosuppressive therapy, some died of serious complications (such as acute respiratory distress syndrome, fungal infection, and pneumocystis pneumonia). The prognosis of patients with severe renal failure was especially poor. We conclude that early diagnosis, treatment and intensive care during immunosuppressive therapy are very important in the management of MPO-ANCA-positive rapidly progressive glomerulonephritis.

Adolescent↗
PubMed1995

Transmission of hepatitis C virus by health care workers in a rural area of Japan.

OBJECTIVE: The prevailing route of hepatitis C virus (HCV) transmission in Japan is unclear, so we expected that a survey of routes of HCV infection in an endemic area might clarify the mode of transmission. METHODS: We screened 2049 inhabitants in an isolated rural village of Fukuoka, Japan using HCV markers. All serum samples were assayed for antibody to HCV (anti-HCV) (ELISA), and anti-HCV-positive samples were assayed for HCV RNA and genotype (polymerase chain reaction). RESULTS: The prevalence of anti-HCV was 19.7% and increased with advancing age, from zero in the under 19 yr of age group to 30.7% in the 60-69 yr of age group. HCV RNA was detected in 82.9% of the anti-HCV-positive inhabitants, and 88.3% of them had genotype II. Anti-HCV was detected in 17.8% of the children of HCV-carrier mothers, similar to the rate (15.4%) for all inhabitants in the 40-49 yr of age group, the same age group for the mean age of the anti-HCV-positive children. Anti-HCV was detected in 34.8% of husbands of female HCV carriers and in 22.2% of wives of male HCV carriers, similar to the rates (36.2% in males and 26.6% in females) for all inhabitants in 60-69 yr of age group, the same age group for the mean ages of carriers' spouses. The prevalence of anti-HCV was the highest in inhabitants of one of three distinct areas of this village where patients had often been injected with insufficiently sterilized syringes and needles for treatment in the same clinic. CONCLUSION: These observations suggest that medical intervention probably played a more important role in the spread of the HCV infection in the village studied than did familial transmission.

Adult↗
PubMed1995

Human T-lymphotropic virus type-I, and hepatitis A, B and C viruses in Nepal: a serological survey.

In 1987, 676 blood samples were collected from inhabitants of the Bhadrakali and Kotyang villages in Nepal. The samples were tested for the prevalence of antibody to hepatitis A virus (anti-HAV), hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc), second-generation antibody to hepatitis C virus (anti-HCV) and antibody to human T-lymphotropic virus type-I (anti-HTLV-I). Anti-HAV was present in 99.3% of the people surveyed. The prevalence of anti-HAV reached 100% in the < 25 age group and was as high or only slightly lower in all other age groups. The prevalence of HBsAg was 0.3% and of anti-HBc 7.7%. Anti-HCV was found in 0.1% of the residents. No significant difference by gender or village was noted in the prevalence of anti-HAV, HBsAg, anti-HBc, or anti-HCV. No anti-HTLV-I-positive persons were identified. These data suggest that the prevalence of hepatitis B and C virus infections in Nepal is low in contrast to hepatitis A virus infection, and that human T-lymphotropic type-I infection may be absent in this population.

Adolescent↗
PubMed1995

[Cabrol's operation and the aortic arch replacement for Stanford type A dissecting aortic aneurysm].

Replacement of the aortic arch was performed simultaneously with Cabrol's operation utilizing modified selective cerebral perfusion (SCP) in a patient with a Stanford type A dissecting aortic aneurysm. Preoperative arteriography revealed that the dissection involved both common carotid arteries. For this reason, antegrade SCP was performed via the branches attached to the composite graft which were anastomosed to both of the common carotid arteries following clamping under deep hypothermia. The operation was successfully performed, and the patient's postoperative recovery was uneventful. This method of SCP is useful in the treatment of patients with prior difficulty or risk of cannulation.

Adult↗
PubMed1995

[Surgical treatment of 22 primary cardiac myxomas].

We report surgical treatment of 22 patients with primary cardiac myxomas, including 17 left atrial (LA), 3 right atrial (RA), 1 left ventricular and 1 right ventricular myxomas. Eighteen patients manifested congestive heart failure, and an embolic episode was observed in 5 patients preoperatively. Inflammatory laboratory findings were observed in 16 patients. One case of RA myxoma was complex cardiac myxoma. A transverse biatrial approach was useful for removal of large LA myxomas and when the attachment of the tumor was unconfirmed preoperatively. There were no hospital deaths. Stroke occurred in 1 and supraventricular arrhythmia in 3 patients in the early postoperative period. There were 2 late deaths unrelated to cardiac myxomas. No signs of recurrence have been observed.

Aged↗