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Shinichi Oka

Publications and source records attributed to Shinichi Oka.

61 records · Page 4Linked to original sources
PubMed2002

The expression of murine double minute 2 is a favorable prognostic marker in esophageal squamous cell carcinoma without p53 protein accumulation.

BACKGROUND: Murine double minute 2 (MDM2) is an oncoprotein that inhibits the function of p53 tumor-suppressor protein. Although there have been a few reports on MDM2 gene abnormalities, there has been no investigation into expression of the product of this gene in esophageal squamous cell carcinoma. Thus, the clinicopathological and prognostic significance of the product of the MDM2 gene is as yet unknown. METHODS: MDM2 protein expression status was analyzed in surgically resected materials by immunohistochemical procedures. RESULTS: The expression of MDM2 significantly correlated inversely with tumor size, depth of invasion, lymph node metastasis, lymphatic vessel invasion, and stage of disease. However, the expression of MDM2 correlated with neither p53 protein accumulation status nor Ki-67 labeling index. The prognosis with MDM2-positive status was significantly better than that with MDM2-negative status for patients with p53-negative tumors, but not in those with p53-positive tumors. Moreover, multivariate analysis showed that the expression of MDM2 was an independent prognostic factor in patients with p53-negative tumors. CONCLUSIONS: These findings indicate that MDM2 immunohistochemical analysis may provide useful information concerning the prognosis in esophageal squamous cell carcinoma patients with p53-negative tumors.

Aged↗
PubMed2002

[Comparison between HIV-1-infected hemophiliacs and non-hemophiliacs on survival and clinical courses after starting highly active antiretroviral therapy].

In order to investigate the long-term prognosis and clinical efficacy of highly active antiretroviral therapy (HAART) in HIV-1-infected hemophiliacs, we compared clinical courses of 69 HIV-1-infected hemophiliacs and 29 non-hemophiliacs all of whom were asymptomatic between 1990 and 1993. Changes of CD4 count during 1990 through 2000 in both groups were not significantly different. The time to death due to AIDS in both groups were also not significantly different. The major causes of death not related to AIDS in hemophiliacs were bleeding, liver cirrhosis, and liver cancer. A total of 55 (39 hemophiliacs and 16 non-hemophiliacs) out of 98 patients survived in 1997. Since then, the 28 hemophiliacs and the 12 non-hemophiliacs received HAART. Although the percentage of patients whose viral loads (VL) decreased to below undetectable level (VL < 400 copies/ml) by the initial HAART regimens without saquinavir were not significantly different, continuation of the same regimens in the hemophiliacs were significantly longer than non-hemophiliacs (84 weeks vs. 51 weeks, p < 0.05). From starting HAART to July 2000, 35.7% of the hemophiliacs were changed regimens three times or more. That is higher prevalence comparing with non-hemophiliacs of 16.7%. This study suggests that there might be the patient group who have to been changed HAART regimens frequently in the hemophiliacs.

Adolescent↗
PubMed2002

[Pulmonary complications in patients with AIDS].

HIV infection was first reported in 1981 in USA. It has been 20 years since then. Owing to understandings of pathogenesis of this disease and development of new drugs such as the HIV-specific protease inhibitor (PI), prognosis of disease has been tremendously improved. Especially after 1997 in Japan, the strategy of anti-HIV treatment shifted from two drugs combination to three drugs combination, which is called highly active antiretoviral therapy (HAART). HAART was so effective that prevalence of HIV associated opportunistic infections were decreased dramatically. Mortality among hospitalized HIV-infected patients was decreased from 6.7% in 1996 to 2.6% since then in ACC. However, 80% of patients receiving HAART suffered from side effects and 15% of them had to be changed their treatment due to side effects. Furthermore, an unexpected side effect, namely lipodystrophy syndrome (LDS), was emerged among patients who were receiving HAART more than one year. LDS was first reported as re-distribution of lipid such as central obesity with or without lipo-atrophy from extremities and/or face. Now only cosmetic change, but also it is associated with elevation of lipid and glucose level. Therefore, those patients who have LDS are in face of the risk for the ischemic heart diseases. Our survey indicated that the rate of LDS in Japanese patients were almost same as that of Caucasian patients reported elsewhere. Opportunistic infections associated with HIV infection Treatment for HIV infection consists of two major arms; one is use of anti-HIV drugs to prevent development of AIDS described above and the other is diagnosis, treatment, and prophylaxis of opportunistic infections. There are five very important opportunistic infections; Pneumocystis carinii pneumonia (PCP), cryptococcus meningitis, toxoplasma encephalitis, cytomegalovirus (CMV) infection, and Mycobacterium avium complex (MAC) bacteremia. Because if these five were able to diagnose, a patient can survive under appropriate treatment. On the other hand, if these were not diagnosed, patient must be AIDS death. After introducing HAART, number of CMV retinitis, MAC bacteremia, and AIDS dementia complex were decreasing. However, number of PCP sustained high because PCP is the first indicator disease of AIDS if the patient did not know his HIV status. The first choice of drug is sulfamethoxazole/trimethoprim (ST) for PCP treatment. If the patient were in severe respiratory failure, corticosteroid is used concomitantly. Treatment is usually continued for 3 weeks. We have successfully treated 45 out of 47 cases of PCP for 4 years. However, those patients treated with ST for 3 weeks were limited only 35% because of very high rate of side effects of ST. If the patient was intolerant to ST, treatment was switched to pentamidine. After finishing the treatment, the patient is to be treated with a 5-day course of oral desensitization to ST. More than 80% of patients who were previously intolerant to ST became successfully getting tolerance by this method.

AIDS-Related Opportunistic Infections↗
PubMed2002

[Initiation of therapy: when and what to start with?].

Introduction of HAART (highly active antiretroviral therapy) has resulted in dramatic reductions in AIDS-related opportunistic complications and death. We have faced, however, severe complications due to HAART such as lactic acidosis and lipodystrophy syndrome. Regimens currently employed in the treatment may be complex, require multiple drugs to take, difficult to tolerate owing to adverse effects, and decrease level of quality of life in some patients. Decisions about when and with what to initiate HAART must take into account the risk-benefit ratio associated with the therapy. In this article, issues that must be considered in determining timing of initiation and choice of anti-retroviral drugs are discussed.

AIDS-Related Opportunistic Infections↗
PubMed2002

[Living donor liver transplantation in a patient with HIV].

Highly active anti-retroviral therapy(HAART) for human immunodeficiency virus(HIV) has delayed the disease progression. The advances prompted us to undertake liver transplantation in a 41-year-old man with hemophilia B, HIV infection, and hepatitis C(HCV) end-stage liver disease. The donor was the patient's elderly brother. His right liver was implanted by the standard method. Two months after the operation, interferon alfa and ribavirin were administered for HCV infection. HCV was eradicated two weeks after the treatment. The HIV viral load is persistently negative and HAART has not been started so far. Utilizing a organ from living relatives should be one of the options to resolve the concern around the utilization of a scarce public source from cadavers for patients who may not have an equivalent survival to HIV negative patients.

Adult↗
PubMed2001

Influence of human immunodeficiency virus type 1 infection on acute hepatitis A virus infection.

To assess the possible influence of human immunodeficiency virus type 1 (HIV-1) infection on the clinical course of acute hepatitis A virus (HAV) infection, 15 HIV-1-infected homosexual men and 15 non-HIV-infected age-matched subjects were compared. HAV load was higher in HIV-1-infected than in non-HIV-infected patients (P<.001). Duration of viremia in HIV-1-infected patients (median, 53 days) was significantly (P<.05) longer than in non-HIV-infected patients (median, 22 days). HIV-1-infected patients had lower elevations in alanine aminotransferase levels than did non-HIV-infected patients (P<.01) but had higher elevations in alkaline phosphatase levels than did non-HIV-infected patients (P<.001). Some HIV-1-infected patients still had HAV viremia when clinical symptoms had disappeared and alanine aminotransferase levels had returned to normal (60-90 days after the onset of symptoms). HIV-1 infection was associated with prolongation of HAV viremia, which might cause a long-lasting outbreak of HAV infection in HIV-1-infected homosexual men.

Acute Disease↗