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Biomedical subjects

M Sata

Publications and source records attributed to M Sata.

At least 181 records · Page 10Linked to original sources

GB virus C (GBV-C)/hepatitis G virus (HGV) infection among intravenous drug users in Japan.

A sero-epidemiologic survey of 74 IVDUs and 86 age-matched controls was performed to investigate the prevalence, clinical significance, and genetic distribution of GB virus C (GBV-C)/hepatitis G virus (HGV) infection among intravenous drug users (IVDUs) in Japan. GBV-C/HGV RNA was detected by reverse transcriptase-hemi-nested polymerase chain reaction (RT-hemi-nested PCR) for the 5'-untranslated region (5'-UTR) in 43.2% (32/79) of the IVDUs compared with 1.2% (1/86) of the controls (P < 0.001). The duration of drug use did not correlate with the prevalence of GBV-C/HGV. Thirteen subjects positive for GBV-C/HGV RNA without HCV RNA had normal serum aminotransferase concentrations. Phylogenetic tree showed that the 32 GBV-C/HGV-positive isolates from IVDUs were classified within a new GBV-C/HGV group, which has been identified mainly in Asian subjects (type 3). The present study illustrated, (1) the high incidence of GBV-C/HGV infection among Japanese IVDUs, (2) GBV-C/HGV alone may not be an important pathogenic factor for hepatic injury, and (3) type 3 GBV-C/HGV was the most prevalent among IVDUs in Japan.

Adolescent↗

Basic fibroblast growth factor regulates proliferation and motility of human hepatoma cells by an autocrine mechanism.

BACKGROUND/AIMS: Basic fibroblast growth factor has mitogenic and angiogenic properties. In this study, we aimed to evaluate the role of fibroblast growth factor in the development and progression of human hepatocellular carcinoma. METHODS: The expression of basic fibroblast growth factor, fibroblast growth factor receptor-1, and a receptor isoform was investigated by in situ hybridization, immunohistochemistry, reverse transcription-polymerase chain reaction, Western blot analysis and confocal laser-scanning microscopy. The influence of exogenous basic fibroblast growth factor on DNA synthesis and motility of human hepatoma cells were also evaluated. RESULTS: Basic fibroblast growth factor and fibroblast growth factor receptor-1 messenger RNAs were present mainly in tumor cells and less so in hepatocytes from noncancerous liver tissue. Immunoreactive products of basic fibroblast growth factor and fibroblast growth factor receptor-1 were observed in tumor cells. The isoform IIIc was expressed in hepatocellular carcinoma tissue and hepatoma cell lines. Exogenous basic fibroblast growth factor stimulated DNA synthesis and motility of hepatoma cells. The effect was more marked in poorly-differentiated hepatoma cells than in well-differentiated hepatoma cells. Fibroblast growth factor-1 expression on hepatoma cells was also more marked in poorly-differentiated hepatoma cells than in well-differentiated hepatoma cells. The stimulated motility on basic fibroblast growth factor was suppressed by an anti-fibroblast growth factor receptor-1 antibody. CONCLUSIONS: Basic fibroblast growth factor may play an important role in the development and progression of hepatocellular carcinoma via an autocrine mechanism involving fibroblast growth factor and its receptor.

Adult↗

Therapeutic effects of restricted diet and exercise in obese patients with fatty liver.

BACKGROUND/AIMS: The incidence of obese patients with fatty liver has recently increased in Japan as well as in the United States and Europe. Fatty liver may occasionally progress to liver cirrhosis. In this study, we have compared the effects of restricted diet and exercise versus no treatment in obese patients with fatty liver. METHODS: Twenty-five obese patients with fatty liver were divided into treated and control groups. Fifteen obese patients followed a program of restricted diet (ideal weight x 25 Cal x kg(-1)) and exercise (walking or jogging) for a trial period of 3 months. No changes in diet or lifestyle were made by the other 10 patients during the same trial period. Blood biochemical tests and liver histology were compared in all patients before and after the trial. RESULTS: In the treated group, weight, blood biochemical data such as aminotransferase, albumin, cholinesterase, total cholesterol and fasting blood glucose values, and steatosis were significantly decreased after the trial. In the control group, there were no significant differences in the clinical and histological findings before and after the trial. CONCLUSIONS: These results indicate that restricted diet and exercise therapy, such as walking and jogging, are useful means of improving blood biochemical data and histological findings in liver tissues related to fatty liver.

Adolescent↗

Formation of black pigment gallstone in a hamster model of experimental cirrhosis.

The relationship between liver cirrhosis and the pathogenesis of black pigment stones has not been clarified. We attempted to induce black pigment stone formation in the gallbladders of hamsters. Male golden hamsters were divided into a cirrhosis group and a control group. Liver cirrhosis was induced by administering drinking water containing thioacetamide. The control group was given tap water. Gallstones at 48 weeks after treatment were examined by stereoscopic microscopy and scanning electron microscopy. The copper content of the black pigment stones was analysed by atomic absorption spectrophotometry. Black pigment stones in the gallbladder were detected in 25% of the cirrhosis group. Their surface and cross-section appeared amorphous. Black pigment stones contained copper. We confirmed the formation of gallstones in an animal model of cirrhosis by thioacetamide. Our findings may contribute to the clarification of the relationship between the pathogenesis of black pigment stones and the pathophysiology of liver cirrhosis.

Animals↗

Transmission routes and clinical courses in sporadic acute hepatitis C.

Between March 1994 and March 1996 we studied transmission routes and clinical courses in eight patients with sporadic acute hepatitis C (two men, six women). Of the eight patients, three were treated for another illness 1-2 months before the onset of hepatitis, one was a parenteral drug abuser, one had an accidental needlestick injury and two had sexual contact with a partner with chronic hepatitis C virus (HCV) infection. Clinical courses included four women whose HCV RNA and alanine aminotransferase (ALT) became persistently negative without treatment, and four men and two women with the same results following interferon (IFN) treatment. It is thought that IFN therapy may prevent the progression to chronic liver disease. Results from this study might be useful in the future management of patients with sporadic acute hepatitis C.

Acute Disease↗

Early therapy with interferon for acute hepatitis C acquired through a needlestick.

Because there is no effective neutralizing antibody or vaccine for preventing hepatitis C virus (HCV) transmission, HCV can be transmitted to health care workers through accidental needlesticks. Recently, two of our health care workers acquired HCV infection through needlestick accidents and developed acute hepatitis C. The route of transmission was confirmed by molecular evolutionary analysis with use of the E2 region of the HCV genome. After the clinical onset of acute hepatitis, the health care workers were treated with interferon (IFN) (total dose, approximately 300 megaunits). Neither individual developed chronic hepatitis. This finding raises the possibility that treatment with low-dose IFN following an accidental needlestick may be beneficial, even when it is started after the clinical onset of hepatitis.

Acute Disease↗

Detection of MAGE-4 protein in the sera of patients with hepatitis-C virus-associated hepatocellular carcinoma and liver cirrhosis.

The aim of this study was to determine whether MAGE-4 protein is detectable in sera of patients with hepatocellular carcinoma and other liver diseases. An enzyme-linked immunosorbent assay was employed for detection of MAGE-4 protein in sera of liver disease patients, healthy men and women (control I) and those undergoing prostatic cancer screening (control II). MAGE-4 protein levels in sera of patients with hepatitis C virus-associated HCC (HCC-C) (n = 45, mean = 2.160 ng/ml) and HCV-associated cirrhosis (LC-C) (n = 55, 1.072 ng/ml) were significantly higher (P < 0.0001) than those of control I (0.327 ng/ml) or control II (0.394 ng/ml). MAGE-4 protein was positive in 21/45 (46.7%) HCC-C patients and 18/55 (32.7%) LC-C patients (cut-off, mean plus 2 SD in healthy controls) but in 0/12 (0%) hepatitis B virus-associated HCC (HCC-B) patients, 3/49 (6.1%) hepatitis B virus-associated LC (LC-B) patients, 4/47 (8.5%) alcoholic liver disease patients, and 1/49 (2.0%) controls. Serum MAGE-4 protein level may be useful as a marker for identification of LC-C patients suffering from HCC that is undetectable by presently available methods.

Adult↗

Hepatitis C virus RNA present in saliva but absent in breast-milk of the hepatitis C carrier mother.

In order to examine whether saliva and breast-milk are mediators of the vertical transmission of hepatitis C virus (HCV) from an HCV carrier mother, serum, saliva, and breast-milk samples from 11 HCV carrier mothers were collected at the time of delivery, and at approximately 1- to 3-months intervals for as long as 30 months postpartum. Serum was also sampled from their children. All samples were analysed for the presence of HCV RNA, using the nested polymerase chain reaction method. No HCV RNA was detected in any breast-milk samples. In saliva, HCV RNA was detected in four of the 11 mothers (36%). These four mothers also had liver function abnormalities. Hepatitis C virus RNA was not detected in any serum samples of the children, and all children had normal liver function. The children were monitored for periods from 2 to 44 months. During this period, there was no evidence of virus transmission. Breast-milk is not likely to be a source of mother-to-child transmission of HCV. Maternal saliva may harbour HCV, but it may not result in infant infection.

Child, Preschool↗

Bafilomycin A1, a specific inhibitor of V-type H+-ATPases, inhibits the acidification of endocytic structures and inhibits horseradish peroxidase uptake in isolated rat sinusoidal endothelial cells.

The role of vacuolar type H+-ATPases (v-ATPases) and pH gradient between the endocytic compartments and cytoplasm in the endocytosis of horseradish peroxidase, a mannose-terminated glycoprotein, was investigated morphologically in isolated rat sinusoidal endothelial cells. Toward this purpose, a specific inhibitor of v-ATPases, bafilomycin A1, was used to inhibit v-ATPases in the vacuolar system. Uptake of horseradish peroxidase was examined by electron microscopy. Fluorescent staining by acridine orange showed that bafilomycin A1 inhibited the acidification of the endocytic compartments. Horseradish peroxidase was taken up via mannose receptors and was distributed in the endocytic structures in the isolated sinusoidal endothelial cells. Uptake of horseradish peroxidase was significantly inhibited by bafilomycin A1, and this finding was confirmed by morphometrical analysis. These results suggest that: a) v-ATPases are necessary for acidification of the endocytic compartments in the sinusoidal endothelial cells and b) the pH gradient between the endocytic compartments and the cytoplasm that is generated by v-ATPases is necessary for the receptor-mediated endocytosis of a mannose-terminated glycoprotein, horseradish peroxidase.

Acridine Orange↗

GB virus infection in patients with oral cancer and oral lichen planus.

We studied the incidence of GBV-C infection in patients with oral cancer or oral lichen planus (OLP). Subjects included 38 patients with oral cancer and 34 patients with OLP from whom serum was collected to detect GBV-C-RNA using reverse transcription (RT) "nested" PCR. GBV-C-RNA was positive in 1 (2.6%) oral cancer patient and 3 (8.8%) OLP patients. All 4 GBV-C-positive patients were also positive both for the antibody for hepatitis C virus (anti-HCV) and HCV-RNA, indicating simultaneous infection with GBV-C and HCV. In conclusion, GBV-C infection was found in 5.5% (4/72) of oral cancer or OLP patients and all patients infected with GBV-C also had HCV infection. This suggests that GBV-C infection is unlikely to play an important role in the pathogenesis of oral cancer and OLP.

Aged↗

Prevalence of hepatitis C antibodies in health care personnel.

To determine the prevalence of hepatitis C virus (HCV) infection in health care personnel in an HCV endemic area, we conducted a seroprevalence study of 1638 Kurume University Hospital physicians, nurses, laboratory staff, and clerical staff (560 men, 1078 women). Antibody to HCV (anti-HCV) was found in 2.8% (46) of subjects and hepatitis B surface antigen was found in 1.1% (18). The anti-HCV positive rate in health care personnel was no higher than reported in the general population of Fukuoka prefecture in Kyushu, Japan. There were no significant differences in anti-HCV positive rate by occupation. However, the prevalence of anti-HCV positive individuals increased significantly as age and length of time in an occupation increased. Anti-HCV positive rate in health care personnel was probably not related to length of time in an occupation. The data suggest that HCV infection is not easily transmitted to health care personnel in an HCV endemic area.

Adult↗

[A case of cat scratch disease identified by an elevated Bartonella henselae antibody level using enzyme immunoassay].

A 68-year-old male was admitted to our hospital because of fever and a 2-week history of inguinal adenomegaly. Since he owned a cat, cat scratch disease was suspected. But it was necessary to distinguish cat scratch disease from lymphoma type adult T-cell leukemia because he showed a high level of antibody against HTLV-1. An excisional biopsy of the inguinal node was performed. Histopathologic examination revealed abscess-forming granulomatous lymphadenitis compatible with cat scratch disease. A Warthin-Starry silver stain showed pleomorphic bacilli in the lymph node. So we confirmed a serological response to Bartonella henselae, the causative agent of cat scratch disease, using enzyme immunoassay (EIA). The IgG antibody level to B. henselae was positive at 42 EIA Unit before treatment. After treatment with intravenous cefepime and oral tosufloxacin, his physical symptoms improved and the antibody level decreased to less than 12 EIA Unit. EIA was very useful for diagnosis of this case. Serology to B. henselae may replace traditional diagnostic criteria for cat scratch disease.

Aged↗

Duration of chronic HCV infection and efficacy of interferon in chronic hepatitis C patients with a history of blood transfusion. The Study Group for Treatment of Hepatitis in the Kyushu Area.

To investigate correlations between the interval between blood transfusion and the start of IFN therapy, and IFN efficacy, we studied chronic hepatitis C patients with a history of blood transfusion. The subjects were 122 patients with chronic hepatitis C and a history of blood transfusion at 64 institutions. The patients were treated with high or low-dose IFN. High-dose therapy consisted of intramuscular injection of human lymphoblastoid interferon (HLBI), 6 x 10(6) IU daily for 2 weeks, then 3 times a week for 22 weeks, and low-dose interferon therapy of intramuscular injection of HLBI, 6 x 10(6) IU daily for 2 weeks, then 3 x 10(6) IU 3 times a week for 22 weeks. Normal serum ALT levels for 6 months or more after completing IFN (complete response) were found in 44/122 (36.2%) patients and HCV RNA was no longer detectable after completing IFN therapy in 19/68 (27.9%). Patients in whom the interval between blood transfusion and the start of IFN therapy was less than 20 years had significantly higher rates of HCV RNA-negative complete response than those in whom the interval was 20 years or more (p < 0.039). When chronic HCV infection is caused by blood transfusion, the efficacy of IFN depends on the duration of chronic HCV infection. Since the duration of HCV infection is a factor in predicting efficacy, early IFN therapy may be more effective.

Adult↗

Reduced contractility and histological changes in the gallbladder due to portal hypertension in a hamster cirrhosis model.

BACKGROUND/AIMS: Little is known about the relationship of portal venous pressure to contractility and histological changes in the gallbladder. In this study, we investigated the relationship between portal hypertension and contractility and histological changes in the gallbladder in a hamster cirrhosis model. METHODS: Liver cirrhosis was induced in the hamsters (n = 20) by thioacetamide (TAA). Portal venous pressure was directly measured using a pressure-measuring instrument. The contractility of the gallbladder was appraised by the diameter before and after caerulein treatment. Gallbladder wall thickness and vessel areas in tissues were evaluated in relation to the portal venous pressure. RESULTS: The portal venous pressure, gallbladder wall thickness with submucosal edema and area of vessels in the gallbladder wall in the cirrhosis group were significantly increased compared with those in the control group (n = 20, receiving saline instead of TAA). The gallbladder contraction rate in the cirrhosis group was significantly decreased compared with that in the control group. In the cirrhosis group, there were positive correlations between the portal venous pressure and the gallbladder contraction rate, gallbladder wall thickness, and area of vessels. CONCLUSIONS: In the gallbladders of experimental cirrhotic hamsters, portal hypertension caused dilatation of the vessels as well as submucosal edema, and was an important factor in the increased thickness and reduced contractility of the gallbladder wall.

Animals↗

Inhibition of neutrophil elastase-induced interleukin-8 gene expression by urinary trypsin inhibitor in human bronchial epithelial cells.

BACKGROUND: Urinary trypsin inhibitor (UTI), a potential inhibitor for proteinases including neutrophil elastase (NE), trypsin, plasmin, cathepsin B and H has been used for the treatment of lung diseases with the absence of side effects in Japan. METHODS: In this study, we investigated the inhibitory effects of UTI on both purified NE and NE activities present in bronchoalveolar fluids from patients with chronic bronchitis. We also investigated the inhibitory capacity of UTI with regard to NE-induced interleukin-8 gene expression in human bronchial epithelial cells by Northern analyses. RESULTS: UTI inhibited NE activities in bronchoalveolar lavage fluid from patients with chronic bronchitis and of the purified enzyme. In addition, UTI inhibited NE-induced interleukin-8 gene expression and protein secretion in a human bronchial epithelial cell line. CONCLUSIONS: Our results suggest that UTI is applicable to patients with a variety inflammatory lung diseases in which NE plays a pivotal role.

Bronchi↗

Elevated levels of cytokeratin 19 in the bronchoalveolar lavage fluid of patients with chronic airway inflammatory diseases--a specific marker for bronchial epithelial injury.

Cytokeratin 19 (CK19) is a specific cytoskeletal structure of simple epithelia, including bronchial epithelial cells (BEC). Since CK19 is released from injured bronchial epithelium, we investigated the levels of CK19 fragments in the bronchoalveolar lavage fluid (BALF) of eight patients with chronic airway inflammatory diseases (CAID) using an enzyme-linked immunosorbent assay (ELISA). Included in our test group were four cases of chronic bronchitis, three cases of bronchiectasis, and one case of diffuse panbronchiolitis. There were also 15 control subjects (five asymptomatic smokers and 10 nonsmokers). BALF from the nonsmokers as well as from the asymptomatic smokers contained few CK19 fragments (0.2 +/- 0.2 and 1.9 +/- 0.8 pg/ml, respectively). In contrast, significantly high levels of CK19 were present in the BALF of patients with CAID (21.7 +/- 5.7 pg/ml; p < 0.01 versus nonsmoking controls). In addition, CK19 fragment concentrations in BALF correlated significantly with the number of neutrophils (r = 0.722, p < 0.01) but not with the numbers of macrophages or lymphocytes in BALF. BALF from patients with CAID contained high levels of neutrophil elastase (NE) activity, suggesting that NE might be an important stimulus for the release of CK19 from BEC. To prove this, we incubated BET-1A cells, a human immortalized bronchial epithelial cell line, both in the absence and the presence of inflammatory mediators (including NE, tumor necrosis factor-alpha [TNF-alpha], and hydrogen peroxide). We then measured the concentration of CK19 fragments in the culture supernatants with ELISA. BET-1A cells released CK19 fragments into their culture supernatants after treatment with NE but not after treatment with TNF or hydrogen peroxide. Further, we demonstrated that CK19 cleaved by NE could not be detected by ELISA. Our results suggest that CK19 measurement in BALF is useful for assessing the presence of bronchial epithelial injuries.

Adult↗