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Biomedical subjects

M Sakurai

Publications and source records attributed to M Sakurai.

At least 1,009 records · Page 56Linked to original sources

[Effect of furosemide on ouabain toxicity in guinea pigs (author's transl)].

An attempt was made to study the effect of furosemide on the toxic and lethal dose (LD) of ouabain. Ouabain was infused continuously in guinea pigs anesthetized with urethane. The toxic dose of ouabain was determined by the minimal dose which produced ventricular arrhythmias. The LD of ouabain was 300.8 +/- 13.8 microgram/kg (mean +/- SE) in control guinea pigs. When furosemide was administered in a dose of 2 mg/kg i.v. prior to ouabain, this was significantly decreased to 225.2 +/- 14.1 microgram/kg (P less than 0.01). Furosemide-treated guinea pigs also showed a marked decrease in toxic dose of ouabain. In another series of experiment, the ouabain uptake by the heart and its subcellular fraction were determined by the infusion of 3H-ouabain at a constant rate under the same experimental conditions aforementioned. Approximately 30% decrease in the LD of 3H-ouabain was also observed in the furosemide pretreated guinea pigs. 3H-ouabain concentration in blood, cardiac muscles and microsomal fraction were lower than control group. These findings suggest that potentiation of ouabain toxicity produced by furosemide is not associated with increased cardiac ouabain uptake, but with increased sensitivity at the site of action.

Animals↗

Hepatitis B surface antigen and chronic hepatitis in infants born to asymptomatic carrier mothers.

Twenty-three infants born to asymptomatic hepatitis B surface antigen (HBSAg) carrier mothers were followed up to determine the vertical transmission of hepatitis B virus. Four infants became positive for HBSAg within four months after birth. Three showed hepatic dysfunction; liver biopsy specimens demonstrated mild chronic hepatitis in one and persistent hepatitis in another. In six infants followed up for more than six months after birth, antibody to HBSAg (anti-HBS) without antigenemia could be detected. Antigenemia of cord blood strongly suggested that hepatitis B viral infection of the infant would occur. HBSAg was also demonstrated in breast milk by radioimmunoassay in three cases. These findings indicate that vertical transmission of hepatitis B virus occurs in many infants born to asymptomatic HBSAg carrier mothers, and that some of them become persistent carriers or develop chronic hepatitis without showing any signs suggesting hepatic involvement.

Biopsy, Needle↗

Diagnostic skin test reactions with varicella virus antigen and clinical application of the test.

Varicella virus antigen was prepared and used in skin testing of 75 children one to 17 years old. Results of skin tests were analyzed in relation to history of varicella, presence of absence of neutralizing antibody, and susceptibility to clinical varicella. All 22 children with no history of varicella and no neutralizing antibody were negative in the skin test when an erythematous change of greater than or equal to 5 mm in diameter was taken as a positive result. Of the 53 children with neutralizing antibody, only three were negative in the skin test. The skin test was applied clinically in an institution for mentally retarded children immediately after varicella infection occurred in a patient. A total of 65 patients were examined by the skin test, and 24 children with negative results were given live varicella virus vaccine. As a result, no spread of varicella was observed except for three cases, which developed two weeks after onset of illness in the index case. Thus the skin test seems clinically useful in the determination of susceptibility of individuals to clinical varicella.

Adolescent↗

Application of a live varicella vaccine in children with acute leukemia or other malignant diseases.

A live varicella vaccine was used in 11 susceptible children in remission from acute leukemia, ten of whom had been in remission for six months or less, and in 6 children with neuroblastoma and retinoblastoma. In the immunological checkup before vaccination, most of them showed a positive reaction in the skin tests with dinitrochlorobenzene, phytohemagglutinin, purified protein derivative, and viral antigens. Leukopenia (three cases, less than 3,000/cu mm) and decreased IgG level (two cases, 380 mg/dl and 445 mg/dl) were observed in the children with leukemia. Anticancer medication was suspended from one week before vaccination to one week after vaccination. The only clinical reaction was a minute rash that appeared three weeks after vaccination in two children with leukemia and that disappeared within three days. Serological responses by complement fixing and neutralizing (NT) tests were detected in all the vaccinated children four weeks after vaccination, and NT antibody was still detected 28 months after vaccination in the two patients tested. Three of the vaccines were exposed to natural varicella at home and in the classroom 2 to 18 months after vaccination, but they were free from any varicella symptoms.

Acute Disease↗

Orcein staining of hepatitis B surface antigen in paraffin sections of liver on autopsy cases.

Paraffin sections of liver on 227 autopsy cases were stained by a modified orcein method of Shikata et al (14) in order to detect hepatitis B surface antigen (HBsAg). Blood of all the 227 cases obtained at autopsy were tested for HBsAg by immune adherence hamagglutination method (7) and for antibody to HBsAg (anti-HBs) by passive hemagglutination method (6). Cases of seropositive in HBsAg but negative in anti-HBs group showed orcein-positive hapatocyte in 13 (68%) of 19 cases of cirrhosis with hepatoma, in 2 (67%) of 3 cases of cirrhosis without hepatoma, and in 2 (67%) of 3 cases of non-cirrhotic neoplastic diseases other than hepatoma. Cases of seronegative in both HBsAg and anti-HBs group showed orceinpositive hepatocyte in 4 (17%) of 24 cases of cirrhosis with hepatoma, in 2 (11%) of 19 cases of cirrhosis without hepatoma, and in 3 (5%) of 60 cases of non-cirrhotic neoplastic diseases other than hepatoma. Cases of seronegative in HBsAg but positive in anti-HBsAg but positive in anti-HBs group showed orcein-positive hepatocyte in 1 (17%) of 6 cases of cirrhosis with hepatoma and in 1 (5%) of 21 cases of non-cirrhotic neoplastic diseases other than hepatoma. Cases of seropositive in both HBsAg and anti-HBs group showed orcein-positive hepatocyte in 1 (33%) of 3 cases of cirrhosis with hepatoma. No orcein-positive hepatocyte was detected in cases of hepatoma without cirrhosis and in cases of non-cirrhotic non-neoplastic diseases in any serological groups.

Autopsy↗

Chromosomes and causation of human cancer and leukemia. XI. Correlation of karyotypes with clinical features of acute myeloblastic leukemia.

Acute myeloblastic leukemia (AML) patients with chromosomal abnormalities in their bone marrow cells were divided into those with minor karyotypic abnormalities (MIKA) and those with major karyotypic abnormalities (MAKA). One of the largest subgroups in the MIKA group was shown to have cytologic characteristics typical of so-called "classical" AML and a "prototypic" karyotype, which has been shown to be due to translocation between chromosomes number 8 and number 21. A missing Y chromosome in AML was mostly associated with this karyotype. Patients of the MAKA group were usually erythroleukemic, had no or very few normal metaphases among the abnormal ones in the marrow, and almost invariably showed karyotypic instability. Karyotypic differences did not affect the patients' survival after the initiation of chemotherapy as much as did the presence or absence of normal metaphases. However, the karyotypes do appear to be relevant to the decision as to whether a patient should be administered chemotherapy when no normal metaphases are found on the initial bone marrow examination.

Adolescent↗

Chromosomes and causation of human cancer and leukemia. XIII. An evaluation of karyotypic findings in erythroleukemia.

This study was an attempt at defining the cytogenetic features of erythroleukemia (EL), particularly as related to the group of AML patients with MAKA (major karyotypic abnormalities), which generally were caused by three or more cellular events of translocation or nondisjunction. Eight of the 17 patients with MAKA had a diagnosis of EL or possible EL. In most cases, MAKA was featured by hypodiploidy, karyotypic instability, and polyploidy in the leukemic cells. The most common abnormalities were loss of B or G group chromosomes and gain of a no. 16 or one or more marker chromosomes. Each of the markers of 2q+, Dq+, mar(A2, st), mar(C12, M), r(?F) and minute metacentric and acentric markers was observed in two or more patients. The extent of polyploidy seemed to be correlated with the proportion of erythroid precursor cells in the marrow and with the karyotypic instability. Since the patients exhibited the same chromosomal features, whether or not they had a diagnosis of EL or possible EL, and since patients without such a diagnosis also had cytologic suggestions of EL, a close relation of MAKA to EL is assumed. It is believed that patients with MAKA constitute one of the three chromosomally classifiable groups of EL.

Bone Marrow↗

The chromosomes and causation of human cancer and leukemia. XVIII. The missing Y in acute myeloblastic leukemia (AML) and Ph1-positive chronic myelocytic leukemia (CML).

The occurrence of a missing Y chromosome was investigated in the bone marrow cells of male individuals, i.e., 255 controls, 73 with acute myelocytic leukemia (AML) and 59 with Ph1-positive chronic myelocytic leukemia (CML). The incidence in controls of individuals with 45,X cells increased with age, particularly after the age of 60. In AML, 45,X metaphases were detected in two patients over 70 years of age, but the leukemia seemed to have involved the 46,XY cells rather than the 45,X cells. Four of the six patients with No. 8-No. 21 translocation and two of the 16 with major karyotypic abnormalities (MAKA) exhibited a missing Y in the leukemic cells in addition to other karyotypic aberrations. Four of the Ph1-positive CML patients exhibited a missing Y in all or nearly all the cells in the bone marrow along with the Ph1. In one patient, additional chromosome abnormalities involved the 46,XY,Ph1 rather than the 45,X,Ph1 cells. The genesis of the missing Y in CML cells may be related to the presence of the Ph1, though apparently the patient's age also plays a role. It is our hypothesis that 45,X or 45,X,Ph1 cells are resistant to the development of further chromosomal abnormalities and, thus, reflect their resistance to being involved in an acute leukemic process.

Adolescent↗

Pancreatic carcinoma in infancy. An electron microscopic study.

A case of a malignant epithelial tumor of tail of the pancreas in a 3-year-old Japanese girl is presented. This is the fourth case reported with ultrastructural study. This type of pancreatic carcinoma of the infant has no endocrine granules or endocrine function. The ultrastructural study suggests that the tumor is derived from a primitive epithelial cell with differentiation toward acinar cell.

Adenoma, Islet Cell↗