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Biomedical subjects

M Hosono

Publications and source records attributed to M Hosono.

At least 199 records · Page 11Linked to original sources
PubMed1979

Studies on the resistance to tolerance induction against human IgG in DDD mice. II. Tolerogen-resistant T-cell population in the spleen.

Further studies were carried out to investigate cellular sites of the resistance to the induction of immunological tolerance to HGG in DDD mice, assuming the presence of a subset of tolerogen-resistant splenic T cells. Spleen-seeking T cells were shown to be relatively resistant in comparison with lymph node-seeking T cells. The existence of a tolerogen-resistant T-cell subpopulation was indicated from the experiments demonstrating that tolerance was easily attained after adult thymectomy and that lymph node T cells became much more resistant to tolerance induction after adult splenectomy. The latter experimental result might also exclude the possibility of differences in microenvironment (probably in A cells) between spleen and lymph node. An attempt was made to investigate a possible involvement of A cells in the induction of tolerance. A cells were deprived in vivo by irradiation of the host 3 days prior to spleen cell transfer and in vitro by passing a spleen cell suspension through a Sephadox G-10 column. The deprivation of A cells resulted in priming of the host by the tolerogen rather than easier tolerance induction. No suppressive activity was observed in lymph node cells from tolerized mice. These results suggest that there exists a set of T cells, generated relatively recently in the thymus, preferentially migrating into spleen and there becoming resistant to tolerance induction.

Animals↗
PubMed1977

Resistance to tolerance induction and age-dependent cellular changes in SJL mice.

SJL mice became resistant to tolerance induction between the 2nd and 6th week of life. The effect on tolerance induction of radioresistant accessory (A) cells does not depend on the age of the donor, i.e. is the same whether the A-cell donor is 3 or 12 weeks old. In the thymectomized recipient, reconstituted with spleen cells of 12-week-old donors, resistance to tolerance is greater than in the corresponding intact animal. Resistance to tolerance is due to a change in the T cells, occurs at a different rate in the T cells of thymus and spleen, and my be due to change in the relative proportion of different T-cell subpopulations.

Aging↗
PubMed1977

Tolerance induction as an index of age-related changes.

Tolerance to rabbit gamma globulin RGG) can be induced in newborn or three week old mice of all strains tested. In six week old SJL or NZB mice there is marked resistance against tolerance induction to RGG. This resistance increases with increasing age and is completed by the age of 12 weeks. Resistance to tolerance can be observed in 3 week old SJL animals when human IgG3 but not when human IgG1 or RGG is employed as tolerogen. Using IgG3, resistance to tolerance induction can be demonstrated in 28-34 week old A/J, C57BL/6J and DBA1/J mice. Thus resistance to tolerance induction seems to be a concomitant of aging; SJL and NZB differ from other strains only by the age at which this change is apparent. By the 6th week of age, SJL and NZB mice develop marked resistance to tolerance induction with RGG, and so do hybrids between these two strains; there is no complementation with respect to resistance against tolerance induction. Aggregate-freed iodinated rabbit gamma globulin (125I-RGG) but not mouse immunoglobulin is eliminated much more rapidly from the body of normal 6 week old SJL and NZB mice than from the body of hybrids. Complementation in the hybrids might occur and prevent a response to small quantities of aggregate-freed RGG.

Aging↗
PubMedDate not supplied

Bilio-enteric anastomosis as a risk factor for postembolic hepatic abscesses.

In 2 patients who had undergone pancreatoduodenectomy with choledochojejunostomy, a subsequently detected metastatic tumor of the liver was treated with transcatheter arterial embolization. Weeks later intrahepatic abscesses developed. Pathophysiologic processes that may lead to this complication of hepatic embolization are discussed.

Adult↗
PubMedDate not supplied

A novel murine model of aging, Senescence-Accelerated Mouse (SAM).

Senescence-Accelerated Mouse (SAM) has been under development by our research team at Kyoto University since 1970, based on the AKR/J strain donated by the Jackson Laboratory in 1968. The SAM mouse has an accelerated senescence and age-associated pathologies such as senile amyloidosis, senile osteoporosis, degenerative joint disease, cataract, deficits in learning and memory, brain atrophy, hyperinflation of lungs, hearing impairment and so on. SAM research is advancing world-wide and attempts are being made to clarify fundamental mechanisms involved in primary aging processes, pathogenesis of age-associated pathologies and effective methods to modulate or ameliorate the advance of senescence and disease processes involved in age-associated pathologies.

Journal Article↗
PubMedDate not supplied

CT manifestations of a ruptured hepatic tumor after transcatheter arterial embolization.

There are few reports of the radiologic diagnosis of ruptured hepatic tumors. In a patient with right upper abdominal pain and impending shock, angiography demonstrated a hypervascular hepatic tumor, and CT imaged an extrahepatic mass suggestive of a hematoma. Following transcatheter arterial embolization with Lipiodol Ultrafluide and gelatin-sponge, multiple contiguous CT sections revealed numerous lipiodol droplets adjacent to a lipiodol-containing hepatic tumor, clearly outside the liver. These findings were indicative of a ruptured hepatic tumor. After embolization, the patient's condition improved and he was discharged.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

3D-spiral CT of multiple exostoses.

We report pre- and post-operative three-dimensional (3D)-spiral CT images in a patient with multiple exostoses. Images of 3D-CT, which were performed using the integrated 3D software of the CT system, showed the exact shapes and locations of the individual tumors around the knee joint in comparison with the surgical findings and resected specimen. 3D-spiral CT images of multiple exostoses would be useful for the planning of surgical procedure.

Adolescent↗
PubMedDate not supplied

MRI and scintigraphic features of extraabdominal desmoid tumors.

To determine whether extraabdominal desmoid can be correctly diagnosed using both magnetic resonance imaging (MRI) and scintigraphy with pentavalent technetium-99m dimercaptosuccinic acid and gallium-67 citrate, MRI (T1- and T2-weighted images) and scintigraphy were performed in 18 patients with 27 histologically proved extraabdominal desmoid tumors. The extraabdominal desmoid tumors were characterized by positive uptake of pentavalent technetium-99m dimercaptosuccinic acid and lack of uptake of gallium-67 citrate on scintigraphy. These tumors were isointense to skeletal muscle on T1-weighted MRIs and hyperintense on T2-weighted images. They also displayed septum-like internal inhomogeneity and surrounding hypointense capsular band. The combination of scintigraphy and MRI is of value in correctly diagnosing extraabdominal desmoid tumors except in the rare case of fibrotic verylow-grade sarcoma.

Desmoid Tumors↗
PubMedDate not supplied

Immune abnormality in relation to nonimmune diseases in SAM mice.

A series of related strains of senescence-accelerated mouse (SAM) shows strain-unique age-related diseases, such as amyloidosis, deficit in learning and memory, osteoporosis, and brain atrophy, while many of these disease-prone mouse (SAMP) strains have impaired immune activity as young adults, and have a short life span, probably not due directly to the diseases. Because the mean life span was prolonged and the time of the disease onset was delayed by a low-calorie dietary condition or a specific pathogen-free environment, both of which ameliorate the impaired immune activity, the enhancement of immune activity may help decrease the deteriorative process of aging, to that seen in ordinary strains of mice. Studies using the SAMP model may help elucidate the role of immunity in the aging process. Herein, we review the cellular and genetic basis of the immune abnormality in SAMP mice, then discuss the relationship between immune abnormality and development of the age-related disease, senile amyloidosis, findings obtained on SAMP hybrid mice and congenic mice for disease-related genes. Activation of the gene(s) for senile amyloid per se shortened the life span, and the early development of the immune dysfunction primarily seems to be both genetically and physiologically independent of amyloidosis, although the disease may be indirectly modified in the aged with depressed immune activity.

Aging↗
PubMedDate not supplied

Oligodendroglioma with cystic component in infant.

In this report, we examine the case of a 6-year-old girl with a mixed oligodendroglioma demonstrating uncommon neuroradiological images. CT and MR showed an intratemporal mass with multilocular cystic formation and intratumoral massive calcification, suggestive either of astrocytoma, dysembryoplastic neuroepithelial tumor, or ganglioglioma as a presumptive differential diagnosis. The tumor was almost completely removed. Post-operative histological examination revealed a mixed oligodendroglioma with a small component of astrocytoma. The combination of radiotherapy and chemical treatment was supplemented.

Antineoplastic Agents↗
PubMedDate not supplied

Granulocyte-colony stimulating factor enhances anti-tumour effect of hyperthermia.

The combined effect of granulocyte-colony stimulating factor (GCSF) and hyperthermia in the treatment of experimental tumours was studied to examine the possible involvement of activated granulocytes in the antitumour effect of hyperthermia. Two weeks after transplantation of SCC VII cells (1 x 10(5)) into the instep of the left leg of C3H/HeJ male mice, the mice were given subcutaneous injections of GCSF (0.2 mg/kg) for 4 days. On day 4, hyperthermia was applied locally at 43 degrees C for 40 min. Hyperthermia inhibited the tumour growth, and this effect was enhanced by pre-treating the animals with GCSF. The numbers of circulating neutrophils in control and GCSF-treated mice were 2728 +/- 517/microl and 3124 +/- 194/microl, respectively (p = 0.53). Hyperthermia increased the number of neutrophils to 4409 +/- 700/microl (p < 0.05). Hyperthermia combined with GCSF significantly increased the number of netrophils to 5479 +/- 691/microl (p < 0.01). Chemiluminescence analysis using L-012 revealed that GCSF enhanced the generation of reactive oxygen species by about 10-fold. Glutathione contents in tumours 24 h after hyperthermia decreased by about 50% in both the hyperthermia groups with or without GCSF, as compared to those in the control. The GCSF-enhanced anti-tumour activity of hyperthermia was markedly inhibited by administration of a long-acting superoxide dismutase derivative (SM-SOD). These results suggest that GCSF activates the ability to generate active oxygen species by neutrophils and, thereby, enhances the anti-tumour effect of hyperthermia.

Animals↗