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Biomedical subjects

M Imai

Publications and source records attributed to M Imai.

At least 577 records · Page 32Linked to original sources
PubMed1979

Shift from free "small" hepatitis B e antigen to IgG-bound "large" form in the circulation of human beings and a chimpanzee acutely infected with hepatitis B virus.

Hepatitis B e antigen (HBeAg) occurs both free and in association with IgG in the circulation of individuals infected with hepatitis B virus (HBV). We determined free and IgG-bound HBeAg forms separately in the serum of humans and a chimpanzee acutely infected with HBV. In a patient with laboratory acquired HBV infection, the proportion of free HBeAg gradually decreased from 89% to 23%. A similar shift from free to IgG-bound form of HBeAg was invariably observed in 5 additional patients with acute Type B hepatitis. In a chimpanzee that had been experimentally inoculated with HBV, free HBeAg appeared first, then gradually and completely shifted to the IgG-bound form. Finally, IgG-bound HBeAg disappeared, and antibody to HBeAg was detectable in the serum. The determination of both free and IgG-bound forms of HBeAg may provide valuable information, because their ratio reflects the stage and prognosis of acute HBV infection.

Acute Disease↗
PubMed1978

Effects of prostaglandins on Na transport in isolated collecting tubules.

Direct tubular effects of prostaglandins (PG's) on Na transport were examined in isolated cortical and medullary collecting tubules of rabbits perfused in vitro. The animals were treated with deoxycorticosterone acetate (DOCA, 1 mg kg-1 day-1, i.m.) for 3-6 days before experiments. In the cortical collecting tubules PGE2 (1.2 X 10(-7)-2.5 X 10(-5) M), E1 (1.2 x 10(-5) M) and F2alpha (1.2 x 10(-5) M) added to the bath caused reversible decreases in transtubular potential difference (PDt). But neither PGE2 (1.2 X 10(-5) M) added to the perfusate nor PGA2 (1.2 X 10(-5) M) added to the bath had an effect on PDt. The net Na absorption was decreased with PGE2 (1.2 X 10(-5) M) added to the bath from 8.6 +/- 1.36 to 1.5 +/- 1.04 pEq cm-1 s-1 (P is less than 0.02). In rabbits not pretreated with DOCA, the net Na absorption was reduced from 2.73 +/- 0.74 to 1.02 +/- 0.74 pEq cm-1 s-1 (P is less than 0.01). In the outer medullary collecting tubules PGE2 (1.2 X 10(-5) M) added to the bath also caused a reversible decrease in PDt. It is concluded that PGE2, F2alpha and E1 inhibit Na absorption in the collecting tubules by acting on the peritubular membrane.

Animals↗
PubMed1978

Duality of hepatitis B e antigen in serum of persons infected with hepatitis B virus: evidence for the nonidentity of e antigen with immunoglobulins.

Hepatitis B e antigen (HBeAg) is detected in the serum of some persons infected with hepatitis B virus. Owing to a close correlation of HBeAg and hepatitis B virus in the serum, it has been used as a practical indicator of infectivity. Two entities of HBeAg activity physicochemically different from each other were demonstrated in the serum of persons infected with hepatitis B virus. One was associated with a molecule that precipitated in 1.33 M ammonium sulfate solution, was larger than IgG, and had an electrophoretic mobility in the beta- to gamma-globulin regions and an isoelectric point of approximately pH 5.7. In contrast, the other HBeAg activity was associated with a molecule that was soluble in 1.33 M ammonium sulfate solution, was smaller than IgG, and had an electrophoretic mobility in the alpha-globulin region and an isoelectric point at pH 4.8. In spite of their marked physicochemical differences, a line of antigenic identity was clearly observed for them when they were tested against antibody to HBeAg by a them when they were tested against antibody to HBeAg by a double immunodiffusion method. The HBeAg activity associated with the large molecule was completely removed by an affinity column of anti-IgG, whereas the activity of the small molecule was not. These results indicate that, in the serum, HBeAg exists as a molecule smaller than IgG and also in association with IgG.

Electrophoresis, Disc↗
PubMed1978

Failure of antibody to e antigen to precipitate Dane particles containing DNA polymerase activity and hepatitis B core antigen.

Serum samples of 67 asymptomatic carriers were tested for Dane particles by electron microscopy, and for e antigen by immunodiffusion, as well as for hepatitis B antigen-associated DNA polymerase activity, and four samples enriched with respect to Dane particles were selected. Hepatitis B antigen particles in them were separated from e antigen and concentrated by centrifugation, and the Dane-rich preparations were incubated with buffer, antibody to e antigen (anti-HBe) or antibody to hepatitis B surface antigen. After centrifugation, the supernatant was tested for DNA polymerase activity, and both supernatant and precipitate were tested for hepatitis B core antigen (HBcAg) by the immune adherence haemagglutination method after the coat of the Dane particles had been disrupted with NP-40 and 2-mercaptoethanol. It was found that anti-HBe did not precipitate Dane particles as measured by DNA polymerase activity and HBcAg. On the basis of the results obtained, it has been concluded that e antigen does not exist on the surface of hepatitis B virions.

Antibodies, Viral↗
PubMed1978

Pathological studies on a long-term survived case of gamma heavy chain disease--a brief review of 30 reported cases and a proposal for histological typing.

A pathological and brief clinical study on the eleventh case of gamma heavy chain (gamma-chain) disease who died at the age of 44 after a long course of 12 years from the assumed onset of the disease was presented. Clinicopathological observations of the case showed a neoplastic nature which caused her death complicated by asthmatic attacks. Autopsy findings were characterized by diffuse infiltration of lymphoplasmacytoid cells and a few large immunoblastic cells into various organs. Literatures of 30 cases reported in the past, and the modern concept of lymphoma strongly suggest that the classificatory position of gamma-chain disease as well as Waldenström's macroglobulinemia should be placed between multiple myeloma and classic malignant lymphoma as an independent disease entity belonging to the same category. A proposal of histological typing of the disease was made in order to simplify various diagnostic designations in the literatures:--gamma-chain disease, 1) reticular type, 2) lymphocytic predominance, 3) plasmacytic predominance, 4) lymphoplasmacytoid cell type, 5) immunoblastic type. The present case belongs to type 4.

Adolescent↗