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Biomedical subjects

A Nagata

Publications and source records attributed to A Nagata.

At least 163 records · Page 9Linked to original sources

[Diastema].

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Child↗

Epidemiology of sporadic acute non-A, non-B hepatitis in Japan: a comparison with hepatitis A and B.

Two hundred fifty-eight patients with clinically and serologically proven sporadic acute viral hepatitis during a period of past 7 years (January 1976-December 1982) were analyzed regarding epidemiology and outcome. The frequency of non-A, non-B (NANB) hepatitis was the highest among the three categories of viral hepatitis; 118 patients had hepatitis NANB (46%), 70 hepatitis A (27%), and 70 hepatitis B (27%). In NANB hepatitis, the mean age was older than in other categories of hepatitis and both sexes were equally affected, in contrast to the male predominance in types A and B. Chronic liver disease developed in 32% of patients with NANB hepatitis, but in none of patients with hepatitis type A or B. These results suggest that in Japan the infectious sources of hepatitis NANB virus(es) are more prevalent than those of hepatitis A and B viruses, and also suggest that one of the possible important factors for the high tendency to chronicity may be concerned with intimate contact with, or evolution from, asymptomatic NANB virus carriers.

Adolescent↗

Isolation and characterization of nucleoid proteins from Escherichia coli.

Of the molecular species of proteins associated with the nucleoids of Escherichia coli cells, those with relatively high affinity to bind to DNA were isolated and characterized. Seven classes of nucleoid proteins with molecular weights of 9,000, 17,000 (two molecular species), 22,000, 24,000, 27,000 and 28,000 were isolated at more than 90% purity or were partially purified. On the basis of its amino acid composition and other chemical properties, the 9,000 dalton protein was identified as HLP II (or HU protein or BH2) (Pettijohn 1982; Rouvière-Yaniv and Gros 1975; Varshavsky et al. 1978). The 17 K protein consisted of two molecular species and one of these, 17 K (a) protein, seemed to be identical with HLPI (or protein 1 or BH1) reported previously (Pettijohn 1982; Varshavsky et al. 1977; Varshavsky et al. 1978). The 26 K protein was identical to the 22 K protein (Kishi et al. 1982). The 27 K protein showed immunological cross-reactivity with the antibody for histone H2A and was thus identified as the H protein reported previously (Hübscher et al. 1980). Two basic proteins, 9 K and 17 K(a), showed relatively high binding affinities to DNA, while the 28 K protein showed moderate binding affinity. The biological significance of these nucleoid proteins, which constitute a family of proteins participating in formation of the nucleoid structure, is discussed.

Bacterial Proteins↗

Quantitative analysis of the production of heat-labile enterotoxin by enterotoxigenic Escherichia coli.

A modified method of passive immune hemolysis (PIH) was applied to the quantitative assay of heat-labile enterotoxin (LT) produced by enterotoxigenic Escherichia coli. The method enabled the measurement of 0.2 to 1.2 ng LT. The production of LT by enterotoxigenic E. coli under various conditions was analyzed using the modified method. LT production was intense during the logarithmic growth phase and decreased during the stationary growth phase. Lincomycin (50 to 100 micrograms/ml) affected cell growth slightly, but enhanced production of LT until the late-stationary growth phase. About 90% of the LT produced was retained in the cell, and the rest was excreted into the culture medium. The initial pH of the culture medium affected LT production. Alkaline pH enhanced LT production, though growth was depressed. Aeration enhanced both growth and LT production.

Aerobiosis↗

Hepatocellular carcinoma after non-A, non-B posttransfusion hepatitis.

A case is reported in which non-A, non-B posttransfusion hepatitis was followed serially by chronic persistent hepatitis, chronic active hepatitis, and liver cirrhosis that finally developed into hepatocellular carcinoma. The patient died after a 19-year clinical course. During the last 8 years, repeated attempts to identify serum hepatitis B surface antigen, antibody to hepatitis B surface antigen, and antibody to hepatitis B core antigen were consistently negative. Liver biopsy was performed five times during the clinical course, and at autopsy, liver tissue was obtained from four different nontumor regions. These specimens were investigated by a peroxidase immunoenzyme method which failed to detect hepatitis B surface antigen and hepatitis B core antigen. Non-A, non-B posttransfusion hepatitis may become chronic and sometimes may advance to hepatocellular carcinoma.

Adult↗

[Pancreatic oncofetal antigen (POA) and carcinoma of the pancreas].

Pancreatic oncofetal antigen (POA) was purified from fetal pancreas and migrated in beta-region electrophoretically. Its molecular weight was 80 X 10(4) daltons. Enzyme immunoassay for serum POA revealed that elevated levels of POA were found in sera of patients with pancreatic cancer. By a serological screening of 440 out-patients with combined assay of tumor markers including POA, 4 cases of pancreatic cancer were found. POA was demonstrated in the ductal cells of fetal pancreas and cancer cells of duct cell type pancreatic adenocarcinoma immunohistochemically. Elevated levels of serum POA of patients with pancreatic cancer was probably derived from cancer tissue. These findings indicate that serum POA assay is clinically useful.

Adenocarcinoma↗

A pancreatic oncofetal antigen (POA): its characterization and application for enzyme immunoassay.

We investigated the usefulness of enzyme immunoassay (EIA) for pancreatic oncofetal antigen (POA). The crude POA isolated from POA-positive ascitic fluid of patients with pancreatic cancer was injected into rabbits to raise anti-POA serum. The adsorbed antiserum was used for EIA as anti-POA serum. For the establishment of EIA system for POA, anti-POA-Fab' fragment was conjugated to beta-D-galactosidase from Escherichia Coli. Normal subjects (205 controls) and 132 patients (47 with pancreatic cancer, 22 with chronic pancreatitis, and 63 with other malignant disease) were surveyed. The standard serum from patient M with pancreatic cancer was used in quantitatively determining serum POA levels; value was expressed arbitrarily as 1000U/ml. Normal upper limit of POA was defined as less than 400U/ml (mean + 2SD of normal subjects). POA level higher than normal was observed in 72% of patients with pancreatic cancer, 23-44% of patients with other malignant diseases, and 18% of patients with chronic pancreatitis. The susceptibility of the isolated POA to several enzymes and chemical reagents was also studied. These results suggest the usefulness of EIA for POA in diagnosis of pancreatic cancer.

Antigens, Neoplasm↗

Exocrine pancreatic cancer with humoral hypercalcemia.

Humoral hypercalcemia associated with malignancy has rarely been reported in exocrine pancreatic cancer. We report a patient with cancer of the exocrine pancreas who presented with hypercalcemia which did not respond to indomethacin. Her serum levels of parathyroid hormone and vitamin D derivatives were low. Technetium diphosphonate bone scan revealed no evidence of bone metastasis, a finding which was confirmed at autopsy. On light microscopy, histological classification of the tumor was moderately differentiated tubular adenocarcinoma. The electron microscopic study, however, revealed a few zymogen-like granules containing cancer cells lying between ductal-type cancer cells. A review of humoral hypercalcemia in cancer of the exocrine pancreas is presented. A humoral factor(s) other than parathyroid hormone, prostaglandin E, and vitamin D derivatives is considered responsible for hypercalcemia in this patient.

Adenocarcinoma↗

A case of asymptomatic primary biliary cirrhosis with an initial presenting feature of localized gastric varices.

A case of asymptomatic primary biliary cirrhosis (PBC) with an initial presenting feature of localized gastric varices is reported. The patient, 64 years old female, underwent a barium meal examination because of ill-defined abdominal complaints and was found to have gastric varices localized at the cardia but no esophageal varices. Her blood chemistry showed high values of biliary tract enzymes such as alkaline phosphatase and gamma-glutamyl transpeptidase, but the serum bilirubin level was almost normal. Serum anti-mitochondrial antibody was positive. Histological findings of the surgically biopsied liver specimen were compatible with PBC. The clinical implication of gastric varices in PBC is discussed.

Female↗

Serum pancreatic oncofetal antigen: its clinical usefulness for screening pancreatic cancer in combination with tests for other tumor markers.

Screening for pancreatic cancer was carried out by serum pancreatic oncofetal antigen (POA) tests in 440 out-patients with abdominal complaints, with concomitant assay of carcinoembryonic antigen, alpha-fetoprotein and ferritin. POA was positive in 13 patients, of whom 3 cases of pancreatic cancer, and 4 of other malignant diseases were diagnosed while the remaining 6 were non-malignant. Of these out-patients, 5 cases were finally diagnosed as having pancreatic cancer by further examinations. Of these 5 patients, POA was negative in 2, of whom one was positive for CEA and AFP. Accordingly, when POA test was applied concomitantly with the other 3 marker tests, the detection rate of pancreatic cancer was elevated to 4/5. Twenty-three patients were found to have malignant diseases and 20 of them were positive for at least one of the 4 markers tested. These results suggest that serum POA assay is useful for screening the pancreatic cancer, especially when the other tumor markers are assayed concomitantly.

Adult↗

Clinical application of the enzyme immunoassay for pancreatic oncofetal antigen.

Pancreatic oncofetal antigen (POA) purified by us has been detected in sera of patients with carcinoma of the pancreas by the micro-Ouchterlony method. In an attempt to improve the sensitivity and clinical usefulness of the serum POA assay, we established an enzyme immunoassay for POA and reported the results with this method. In this study, we investigated serum POA levels in pancreatic cancer and other diseases. The tissue localization of this POA in the pancreas was also studied. For the establishment of the enzyme immunoassay, an anti-POA-F(ab')2 fragment prepared from absorbed antiserum was conjugated with beta-D-galactosidase. The solid-phase "sandwich" principle was used. The normal upper limit of the serum POA level was defined as 400 units/ml. Among 60 patients with pancreatic cancer, 44 had elevated levels (73.3%). Of 22 cases with chronic pancreatitis, 4 had elevated levels (18.2%). In malignant diseases other than pancreatic cancer, elevated levels of serum POA were seen in 17.6% to 48.5% of the patients, most of whom had only slightly elevated levels. These results indicate that enzyme immunoassay for POA is clinically useful for making a diagnosis of pancreatic cancer. Immunoperoxidase staining showed POA to be found at the apical surface of ductular cells in fetal pancreas, at the luminal surface of glandular structures in pancreatic cancer tissue, and also at the luminal surface of the small duct in normal pancreas. Thus it is suggested that a high level of serum POA in patients with pancreatic cancer is derived from pancreatic cancer tissue.

Adult↗

Antibacterial activity of palmitoyltuberactinamine N and di-beta-lysylcapreomycin IIA.

Palmitoyltuberactinamine N (Pal-Tua N) and di-beta-lysylcapreomycin IIA (di-beta-Lys-Cpm IIA), which are synthetic derivatives of the antituberculous agent tuberactinomycin (Tum) and capreomycin (Cpm) respectively, were tested for anti-bacterial activity. Pal-Tua N inhibited not only tuberactinomycin-resistant Mycobacterium smegmatis but also Escherichia coli, Corynebacterium diphtheriae, Staphylococcus aureus, Streptococcus pyogenes, although it has lost activity against Mycobacterium tuberculosis. Di-beta-Lys-Cpm IIA inhibited the growth of laboratory-derived Tum-resistant M. smegmatis and M. tuberculosis as well as Tum-resistant M. tuberculosis from patients with one exceptional case.

Anti-Bacterial Agents↗