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Y Harada

Publications and source records attributed to Y Harada.

At least 847 records · Page 47Linked to original sources

Inhibition and promotion of tumor growth by BCG: evidence for stimulation of humoral enhancing factors by BCG.

Effects of pretreatment with BCG, strain Japan, on tumor growth were studied using a transplatable methylcholanthrene (MCA)-induced fibrosarcoma in C3H/He mice. Injection of BCG7 weeks before tumor inoculation at a site distant from the tumor caused a slight inhibition of tumor growth. A low dose of tumor cells did not grow at the BCG-primed site when BCG was injected 7 and 11 weeks before the tumor. When a high dose was inoculated into the BCG-primed site, inhibition of the primary tumor occurred in mice which had received BCG 7 weeks previously, but the number of distant metastases in the popliteal lymph node and the lungs was increased in mice pretreated with BCG at any time. Furthermore, post treatment with BCG at a site distant from the tumor caused promotion of tumor growth. Enhanced antibody formation and suppression of delayed type hypersensitivity (DTH) occurred in tumor-bearing mice. BCG treatment of such mice caused a vigorously enhanced antibody formation and a marked suppression of DTH. The sera from tumor-bearing mice enhanced tumor growth. Tumor growth was suppressed in splenectomized mice. These findings suggested that antibodies against tumor-specific antigens enhanced tumor growth in this system and that BCG treatment of tumor-bearing mice stimulated formation of antibodies probably acting as blocking factors.

Animals↗

Human otoconia in surgical specimens.

The utricular otoconia of four patients, which were removed during surgical procedures (one for an eighth nerve section operation and three for removal of acoustic neuromas) with the use of the translabyrinthine approach, were observed with the scanning electron microscope. The otoconia of these patients showed some abnormal features. In three of the four patients, a number of otoconia were found to have cracked lines. One of these patients was a 14-year-old boy; the other patients were more than 40 years old. In the remaining case, the otoconial facet surfaces were rough, and a few otoconia were unusually shaped.

Adolescent↗

Mode of immunopotentiating action of BCG: macrophage activation produced by BCG-infection.

Macrophage activation as measured by increased rate of carbon clearance and spreading of peritoneal macrophage was studied in mice infected with BCG, strain Japan. BCG caused marked increase of the numbers of peritoneal cells and spread macrophages. The increases of spread macrophages reached a peak at the 3rd week of BCG infection introduced by the both routes of intravenous(i.v.) injection and foot pad(f.p.) injection. BCG also enhanced the clearance of carbon. In the case of BCG given i.v., the increase of the rate of carbon clearance was biphasic : an early increase reaching maximum at the 1st week and a late increase reaching maximum at the 3rd week of BCG infection. When BCG given into one foot pad, peak increase was reached at the 5th week. The activation of macrophages as measured by increased levels of carbon clearance and increased numbers of spread macrophages in the mice receiving BCG i.v. was approximately two fold greater than that in the mice receiving BCG by f.p. route. When sheep red blood cells (SRBC) as antigen were injected i.v. into the mice primed with BCG i.v., the optimal interval between BCG priming and subsequent antigen injection varied with the dose of antigen for the induction of the highest level of delayed type hypersensitivity (DTH) to SRBC, but not with the degree of macrophage activation.

Animals↗

Mode of immunopotentiating action of BCG: persistence and spread of BCG infection.

The mode of action of BCG, strain Japan was investigated using the immune response to sheep red blood cells (SRBC) as an indicator system. When SRBC were injected into the BCG-primed foot pad, the direct plaque forming cells (PFC) and the effector cells responsible for delayed type hypersensitivity (PTH) were produced in various lymphoid organs widely distributed. Furthermore, bacterial counts in the draining popliteal lymph node and the spleen in the mice inoculated with BCG into the hind foot pad suggested that a local infection with BCG has spread to a generalized systemic infection of lymphoid tissues with time. Enhancement of DTH response to SRBC was induced when the mice previously infected with BCG were inmunized with SRBC mixed with purified protein derivative (PPD). These findings suggested that nonspecific augmentation of immune response with BCG was due to a generalized systemic activation of lymphoid system by BCG infection and the long lasting effect of immunopotentiation with BCG was due to persisting BCG infection in the lymphoid tissues.

Animals↗

Experimental Pseudomonas infection in mice: acquired resistance against Pseudomonas septicemia and altered susceptibility in BCG infected mice.

Pseudomonas septicemia in mice caused the early death in the first three days of infection without any localized lesions. Localized lesions such as abscess are observed in the kidney and liver after the third day of infection. The early death increased in the BCG infected mice showing an increased level of macrophage activation. It seemed that such early death is due to endotoxin produced by Pseudomonas aeruginosa. However, the BCG infected mice showing an enhanced antibody formation were more resistant to pseudomonas septicemia. Immune serum protected such death, but immune spleen cells did not. Furthermore immune serum also protected the increased death in BCG infected mice.

Animals↗

Black hairy tongue. A scanning electron microscopic study.

A patient with tongue malignancy associated with a black hairy tongue is presented. Specimens from e area fo the black hairy tongue and from a normally appearing part were studied with the scanning electron microscope. The "hairs" consisted of elongated filiform papillae due to accumulated keratinized layers. In-between these layers, fungi and bacteria were found. The aetiology of the blck hairy tongue in this patient is discussed.

Humans↗

Membranous tracheitis following endotracheal intubation.

In this study, four patients with membranous tracheitis following endotracheal intubation are presented. Possible causes for the development of the condition were mostly related to subglottic epithelial trauma caused by the pressure of the cuff of the tube for a long time on the mucosa and the drying effect of atropine. The literature concerning the development of membranous tracheitis in previous studies is also presented.

Adolescent↗

The effect of an expectorant on the tracheal mucosa. A scanning-electron microscopic study.

The effect of an intravenous expectorant agent, i.e. Bisolvon, on the secretory activity of the tracheal mucosa of the dog was studied with the scanning electron microscope. A marked increase in the production of tracheal secretion was observed 15 and 30 min following the injection. Both the goblet cells in the epithelium and the seromucinous glands in the tunica propria contributed to the formation of the secretion. 60 min after the injection, the submucosal glands were shrunken or empty. The rapid secretory response to the expectorant, Bisolvon, confirmed the active and important role of the tracheal mucociliary clearance mechanism for the protection of the lower respiratory tract.

Animals↗