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Biomedical subjects

K Aoki

Publications and source records attributed to K Aoki.

At least 919 records · Page 51Linked to original sources
PubMed1979

A test of significance for geographic clusters of disease.

The geographic pattern of disease has been visually studied by depicting the categorized mortality or morbidity rates on a map. Visual study, however, by no means indicates the statistical significance of observed clusters, i.e., whether or not the geographic aggregations could occur by chance alone. In this paper, an approach for assessing the deviation from chance expectation of the geographic pattern actually observed on the map is described. A simple chi-square test is proposed, and its validity is substantiated by a Monte Carlo approach, which is derived analytically as a special case of Knox's test for space--time clustering. The parameters required for the test are (1) total number of areas, (2) numbers of subareas for each mortality of morbidity category, (3) total number of geographically adjacent areas, and (4) observed numbers of adjacent areas having concordant category pairs.

Adult↗
PubMed1979

Potentiation of anticancer effect of carboquone in vivo by glucose pretreatment.

Anticancer effect of carboquone was notably potentiated in tumor-bearing mice when they were pretreated with 5% glucose solution in the system of blood flow-interrupting hyperthermic chemotherapy. It was further found by quantitative analysis that the potentiation was much greater than increase in the general toxicity of the drug by administration of glucose. Mitomycin-C, on the other hand, revealed no such marked effect though it is considerably similar to carboquone in chemical structure.

Animals↗
PubMed1979

Antitumor effect of thermodifferential chemotherapy with carboquone on Ehrlich carcinoma.

A thermodifferential chemotherapy, consisting of systemic administration of antitumor drug and local hyperthermia combined with general hypothermia, was examined and gave satisfactory antitumor results. In search of basic optimal conditions required, this therapeutic system was tested on Ehrlich tumor implanted in the hind limbs of mice. The results obtained were as follows: (a) From the viewpoint of either the antitumor effect or the adverse effect of the therapy, local hyperthermia at 41 degrees for 60 min combined with general hypothermia at 20 approximately 24 degrees was found to be the best thermodifferential condition. (b) The thermodifferential treatment alone without drug administration displayed little antitumor effect. (c) General hypothermia applied not only enhanced the antitumor effect of the drug in loco but also reduced general toxicity of the drug. In the present therapy, carboquone displayed the best antitumor effect among the drugs tested. This suggests that the potentiation of tumoricidal activity of carboquone under the acidic condition produced by cancer cell metabolism in hyperthermia was deeply involved in the effectiveness of this therapy.

Animals↗
PubMed1979

An epidemiologic approach to host factors in the etiology of cancer.

We examined the contribution of host factors in carcinogenesis by evaluating the frequency distributions and secular trends in available epidemiologic data of mortality and morbidity around the world. In most developed countries, the age-adjusted death rates of cancer of all sites have levelled off in recent years and the intercountry difference in mortality is small. Deaths from cancer account for approximately 20% of total deaths in these countries. It is believed that the difference in cancer mortality of all sites between the developed and developing countries can be explained by the different levels of mortality from infectious and parasitic diseases, including deaths from tuberculosis. A certain upper limit for the number of cancer deaths in each population is strongly suggested by the unaltered cumulative mortality rate from cancer and tuberculosis up to 85 years of age in a defined birth cohort in the developed countries. The apparent age dependency in cancer mortality as well as some other essential epidemiologic implications in carcinogenesis, the commonly observed proportion of cancer deaths of around 20% of total deaths, and the well-known etiologic importance of environmental factors which determines the site-specific cancer mortality and morbidity lead one to consider the definite existence of "susceptibles to cancer" in each population. However, the concept of susceptibles to cancer is different from the usual one of hereditary predisposition to so-called "intractable diseases," which have low incidence rates.

Adolescent↗