Biomedical subjects

S Otsu

Publications and source records attributed to S Otsu.

18 recordsLinked to original sources

PubMed2005

Influence of age and duration of infection on bacterial load and immune responses to Helicobacter pylori infection in a murine model.

Using a murine model, we previously showed that Helicobacter pylori infects and colonizes offspring via maternal transmission during the nursing period. The aim of this study was to investigate the influence of age and duration of infection on inflammatory and immune responses to H. pylori in infant and adult mice. During the breast-feeding period, the number of bacteria was significantly suppressed in 1-week-old mice infected with H. pylori at an early stage of nursing, compared with adult mice, suggesting that breast-milk induces such low colonization. In addition, these mice had weaker gastric inflammation, especially Th1 cytokine and humoral responses than in mice infected with H. pylori after weaning in spite of elevated levels of Th1 cytokines. Although infant mice showed low inflammatory responses against H. pylori, they produced H. pylori-specific antibodies following vaccination with oral or parenteral adjuvant. Our results suggest the importance of age at the time of primary infection on bacterial load, gastric inflammation and humoral responses in a murine model of H. pylori infection.

Aging↗

PubMed2003

Childhood Helicobacter pylori infection in a murine model: maternal transmission and eradication by systemic immunization using bacterial antigen-aluminium hydroxide.

In humans, transmission of Helicobacter pylori is thought to occur largely during childhood. Infected mothers are generally considered to be the main source of the pathogen. However, little is known about when and how often maternal transmission of H. pylori occurs during childhood. In the present study, we examined these issues in an experimental murine model. Pregnant C57BL/6 mice, infected experimentally with H. pylori, delivered and nursed their litters. The stomachs of the infants were isolated and assessed for transmission of H. pylori. We also investigated the effect of systemic immunization using H. pylori antigen-aluminium hydroxide (AlOH) with regard to providing anti-H. pylori immunity and eradicating the maternally transmitted bacteria in infants. Polymerase chain reaction (PCR) was used to examine the presence of transmitted bacteria and their eradication. Maternal transmission of H. pylori varied widely during the nursing period, but almost all litters showed bacterial transmission at 2 weeks postpartum. Systemic immunization with bacterial antigen-AlOH eradicated the bacteria in most litters; this immunization induced a local decrease of Th2 cytokines and a local increase of Th1 cytokines in the gastric tissue, as determined by ELISA. Our results indicate that our H. pylori vaccine provides not only protection, but also eradication of the already transmitted H. pylori.

Aluminum Hydroxide↗

PubMed1999

[T cell non-depleted bone marrow transplantation for primary refractory erythroleukemia using a partially HLA-mismatched related donor].

We performed an HLA-mismatched T cell non-depleted bone marrow transplant on a 53-year-old man with acute erythroleukemia that was highly resistant to conventional remission-induction chemotherapy. After conditioning that included total body irradiation, the patient received a two-HLA-antigen-mismatched bone marrow graft harvested from his sister using tacrolimus and methotrexate for graft-versus-host disease (GVHD) prophylaxis. He successfully established rapid engraftment accompanied by steroid-responsive GVHD localized to the skin. Although bone marrow samples on day 31 and day 66 disclosed a complete remission with full donor chimerism, the patient relapsed and died of pulmonary infection on day 154. There is evidence that tacrolimus is effective in alleviating GVHD. Selected patients who have partially mismatched related donors with less HLA disparity may benefit from tacrolimus-based T cell non-depleted bone marrow transplants because of the more potent graft-versus-leukemia effect that can be expected compared to transplants using T cell depleted inoculum.

Bone Marrow Transplantation↗

PubMed1987

Statistical analysis of the organ weights in 1,000 autopsy cases of Japanese aged over 60 years.

For practical use in comparing organ weights of autopsy cases in the aged, and also for evaluating gerontological parameters during human senescence, a method of organ weight standardization was introduced. In the method used in this study, a Gaussian distribution was applied to the main peak that appeared in each distribution of organ weights. The Gaussian distribution best fitted the main peak of the distribution even in the elderly autopsy cases when a large number of cases was accumulated. The smaller peak was adopted in a cardiac weight distribution which showed a double peak because clinicopathological analysis to define a background of the double peak revealed that the larger peak was essentially represented by hypertensive hearts. By using the data from standardized values as well as those from arithmetic means and from means of each individual ratio, the following parameters were obtained: weight ratio of each organ to the body, and weight ratio of each organ and of the body to the brain. In these parameters, comparison of the ratios obtained from standardized values with those obtained by the other procedures showed that the age-related change in the ratios from standardized values were the most reasonably smooth and seemed to be less exaggerated by pathological changes. In elderly autopsy cases, organ changes due to geriatric disorders are difficult to distinguish from those due to ordinary physiological changes, which makes the estimation of "normal values" in the aged problematical. The standardized values obtained in the present study, however, represent mass ecological values and may be applicable as comprehensive practical values in geriatric autopsy pathology as well as in gerontological studies.

Aged↗

PubMed1981