IL-12 protects mice against pulmonary and disseminated infection caused by Cryptococcus neoformans

We examined the role of IL-12 in host resistance to Cryptococcus neoformans using a murine model of pulmonary and disseminated infection. In this model, mice were infected intratracheally with viable yeast cells. Mice untreated with IL-12 allowed an uncontrolled multiplication of yeast cells in the lung with infiltrations of few inflammatory cells, and a cryptococcal dissemination to the brain and meningitis by 3 weeks, resulting in death of all animals within 4–6 weeks. IL-12, when administered from the day of tracheal infection for 7 days, induced a marked infiltration of inflammatory cells, consisting mostly of mononuclear cells, and significantly reduced the number of viable yeast cells in the lung. The treatment suppressed brain dissemination, as shown by a marked reduction of yeast cells in the brain and prevention of meningitis. These effects resulted in a significant increase in the survival rate of infected mice. In contrast, late administration of IL-12 commencing on day 7 after instillation of yeast cells failed to protect the mice against infection with C. neoformans. In further experiments, early administration of IL-12 markedly induced interferon-gamma (IFN-γ) mRNA in the lungs of infected mice, while no IFN-γ mRNA was detected without this treatment. Our results indicate that IL-12 is effective when administered in the early period of pulmonary cryptococcal infection.     

Direct observation of the portal vein interior by intra-operative angioscopy in the dog and man

The purpose of this study was to develop the technique of intra-operative portal angioscopy using a portal angioscope, and to demonstrate its potential use in the therapy for patients with hepatocellular carcinoma (HCC) bearing a portal thrombus. Portal angioscopes, Olympus BF3C10 and CHFP10 of a diameter of 3.5 mm and 4.8 mm, respectively, were used during operation in five dogs, two patients with hepatic metastasis from colon cancer and three patients with HCC having a portal tumour thrombus. The portal vein and hepatic artery were ligated simultaneously, and the angioscope was immediately introduced under direct vision through a small portal venotomy. Blood in the portal vein was almost fully diverted by infusion of heparinized saline through a channel of the angioscope at a rate of 3 mL/min in dogs and 5 mL/min in patients with hepatic metastasis. Rates of 6 mL/min and 10 mL/min in dogs and patients, respectively, were adequate to clear completely the portal vein of blood. In patients with HCC, portal tumour thrombectomy was performed with a Fogarty balloon catheter by suctioning thrombi through a channel of the fibrescope after visual study of the portal thrombus. Observation and treatment of portal thrombus by angioscopy may become an important part of surgical treatment of HCC with portal invasion, but further technical improvement is desirable before this technique becomes a routine procedure.     

Attitudes of medical students towards persons with mental disorders: A comparative study between Japan and Thailand

This study was conducted at three universities, two in Japan and one in Thailand, in order to elucidate the effects of medical education, especially with regard to contact experience on medical students' attitudes toward persons with mental disorders. Questionnaires, which included the Attitudes Towards Disabled Persons Scale (ATDP) and the Contact with Disabled Persons Scale (CDP), were distributed to 1st year students prior to the commencement of their medicine/psychiatry studies and distributed to 6th (or 5th) year students who had completed their psychiatric curriculum. The ATDP scores were lower for 6th year students at all universities, suggesting that post-education students had a more unfavorable attitude than pre-education students. Thai students indicated more unfavorable attitudes than did the Japanese students. Three factors were extracted from the ATDP scale and termed: negation of character, negation of ability and affirmation of normality. Four factors from the CDP scale were extracted and labeled intimate contact experience, ordinary contact experience, unpleasant contact experience and pleasant contact experience. Greater negative attitudes of post-education students than pre-education students were thought to attribute mainly to an increase in factor score of negation of ability and this result was correlated with an increase in factor score of ordinary contact experience in post-education students. Of the three ATDP factor scores, the higher score of Thai students for negation of character contributed to their overall unfavorable attitude scores. The cross-national similarities and differences of students' attitudes towards and contact experience with mentally disordered persons were discussed from the viewpoint of medical education.