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Biomedical subjects

A Yamada

Publications and source records attributed to A Yamada.

At least 19 recordsLinked to original sources
PubMed1979

A role for clonal dominance in the maintenance of allotype suppression?

The establishment of immunological memory during the early and complete phase of allotype suppression in the young rabbit has been shown to lead to the preferential production of antibodies with the nonsuppressed allotypic specificity in response to recall injections given after spontaneous or induced release from suppression. It is suggested that this manifestation of clonal dominance, applied to stimulation by environmental antigens, may contribute to the long lasting persistence of allotype imbalance in allotype suppressed rabbits.

Animals↗
PubMed1979

Radiologic assessment of resectability and prognosis in esophageal carcinoma.

Utilizing double-contrast technique it is possible to detect the earliest malignant lesions of the esophagus even when the carcinoma is confined to the mucosa. In patients with carcinoma, it is also important to attempt to grade and classify the lesion in order to predict its resectability and prognosis. The resectability of a lesion is determined by the depth of invasion and by the presence or absence of lymph node metastases. The significant factors are the length of the lesion, its gross morphology, the character of its margins, and the depth of ulceration. Unfortunately, the depth of invasion is not necessarily directly related to the prognosis. In some carcinomas confined to the submucosa, lymph node metastases are already present, and these patients have a poor prognosis. The presence of lymph node metastases in early carcinoma can be suggested by the gross morphology of the lesion, its length, irregularity of the surface, and the presence of a complex lesion. Careful analysis of the radiographic features of the carcinoma can be valuable for the assessment of resectability and prognosis.

Carcinoma↗
PubMed1979

Asymptomatic infection of mouse hepatitis virus in the rat. Brief report.

After intranasal inoculation of suckling rats mouse hepatitis virus multiplied mostly in the nasal epithelium; though there were no symptoms, antibodies were produced. Antibodies were also demonstrated in adult rats. These findings suggest that the rat may be a natural host for the virus.

Animals↗
PubMed1979

Factors involved in the age-dependent resistance of mice infected with low-virulence mouse hepatitis virus.

Four-week-old weanling mice survived, whereas 1-week-old suckling mice died, after intraperitoneal inoculation of mouse hepatitis virus, MHV-S strain. The factors involved in this difference in susceptibility were studied. After virus inoculation, differences in virus growth in the liver and spleen were observed, which correlated with the susceptibility of animals to the virus. Interferon, detected at an early stage of infection, was considerably lower in suckling mice than in weanling mice. Titers of MHV-S in peritoneal cells from infected animals were at least 100 times greater in suckling than in weanling mice, and a similar, but less prominent difference in virus growth was also found in the corresponding cultured macrophages. After transfer of peritoneal cells from weanling to suckling mice, a decrease in mortality of infected suckling mice was observed. These results suggest that both interferon and macrophages may be important in the age-dependent resistance of mice to MHV-S infection.

Aging↗
PubMed1979

Comparison of 4 serological tests--complement fixation, neutralization, fluorescent antibody to membrane antigen and immune adherence hemagglutination--for assay of antibody to varicella-zoster (V-Z) virus.

Four tests for antibody to varicella-zoster (V-Z) virus were compared; these were tests of complement fixation (CF), neutralization (NT), fluorescent antibody to membrane antigen (FAMA) and immune adherence hemagglutination (IAHA). Fifty-two sera from patients with varicella and zoster and from recipients of live varicella vaccine were examined by the 4 tests. The CF test was least sensitive, but the antibody titers by the NT, FAMA and IAHA tests were roughly comparable. The IAHA test was the simplest and fastest to perform, and appeared suitable for routine serological assay to V-Z virus. The correlation between the IAHA antibody titer and susceptibility of individuals to clinical varicella was investigated retrospectively using sera obtained during 2 outbreaks of varicella in an institution for children, where all the unvaccinated children had developed varicella symptoms. Most of the 25 pre-exposure sera from unvaccinated children examined by the IAHA test had tiers of less than 1:2. In contrast, all the 23 sera from vaccinated children who did not develop varicella had detectable antibody titers of 1:2 to 1:64. These results indicate that the IAHA titer reflects the susceptibility or resistance of individuals to clinical varicella.

Antibodies, Viral↗
PubMed1979

T lymphocyte-dependent difference in susceptibility between DDD and C3H mice to mouse hepatitis virus, MHV-3.

After intraperitoneal inculation with a virulent mouse hepatitis virus, MHV-3, 50% lethal dose in DDD mice was about 7 log10 higher than that in C3H mice. Histopathologically, splenic lymphocytes especially of the thymus-dependent area were more severely affected in susceptible C3H mice than in DDD mice. In the liver of C3H mice, virus multiplied exponentially after inoculation, attaining 10(6) PFU at moribund stage, while virus multiplication in DDD mice was much less prominent decreasing remarkably at day 5 or later. The virus could multiply in the primary culture of spleen cells from C3H mice but not in those from DDD mice, and cells supporting virus growth seemed to be a theta-positive population of lymphocytes. No difference was observed between the two strains of mice in the ability of peritoneal macrophages to support virus growth in vitro as well as serum interferon levels after infection.

Animals↗
PubMed1979

Linear melorheostotic scleroderma with hypertrichosis.

On the basis of clinical features and histological findings, cutaneous manifestations of linear melorheostotic scleroderma are apparently derived from a localized proliferative disorder and are not secondary to bone changes. If the hypertrichosis has the same origin as the osteocutaneous changes, melorheostosis may represent a congenital disorder with both ectodermic and mesodermic components.

Adult↗
PubMed1978

Stable chimerism induced in noninbred rabbits by neonatal injection of spleen cells from alltoype-suppressed adult donors. II. Distribution of donor and recipient allotypes on blood lymphocytes, in serum immunoglobulins, and in specific antibodies.

Long-lasting and stable lymphoid cell chimerism has been noted in three littermates of a group of five rabbits given injections at birth of spleen cells of an allotype-suppressed adult rabbit. The chimeric state manifested itself by the simultaneous display of light and heavy chain markers directed by donor and recipient genotypes in serum immunoglobulins (Ig), on blood lymphocytes, and on antibody molecules made in response to stimulation with three test antigens. Although the genotypes of two of the chimeras were found to be a1a1/b9b9 and the third to be a1a1/b6b9, phenotypically all three were a1a2/b5b6b9. By all of the criteria used to analyze to distribution of allotypes, Ig with the recipients' own allotypes predominated over that controlled by the donor's genotype. With only minor deviations the same proportions of recipient to donor types prevailed in total serum Ig and in the antibody fractions tested.

Animals↗
PubMed1978

Isolation of mouse hepatitis virus from infant mice with fatal diarrhea.

An epizootic of fatal diarrhea occurred in mice which were approximately 10 days of age. The enteric lesions were similar to those reported in lethal intestinal virus of infant mice, but many diseased mice also had necrotic hepatitis. Mouse hepatitis virus antigen was demonstrated in the affected intestine and liver, and a virus that produced syncitium formation in mouse brain tumor cell culture was isolated from the intestines, livers, and brains. The virus was capable of producing intestinal and hepatic lesions similar to the naturally occurring disease after inoculation into suckling mice. Electron microscopy revealed viral particles within affected intestinal epithelial cells of the inoculated mice.

Animals↗
PubMed1978

Acute, subacute and chronic toxicity of oxepinac.

The acute, subacute and chronic toxicity of 6,11-dihydro-11-oxodibenz[b,e]oxepin-3-acetic acid (oxepinac) was investigated in several animal species. The LD50 value was lower in rats than in rabbits, mice and dogs. The major cause of death was perforative ulcer in the gastrointestinal tract. Long-term study in rats revealed that oxepinac produced no hematological, blood chemical and pathological changes except for minor anemia and fatal ulcer formation occurring predominantly in females. Oxepinac proved to be less toxic than indometacin in chronic toxicity in rats.

Acetates↗