A case-control study of lung cancer with special reference to asbestos exposure.

A case-control study of lung cancer was carried out in Yokosuka City, Kanagawa Prefecture, the location of a pre-war Japanese Imperial naval factory and present site of a U.S. naval base. Cytologically or pathologically confirmed male fatal cases of lung cancer during the period of 1978 to 1982 in Yokosuka Kyosai Hospital were compared with a control group in the same hospital. Controls who died from causes other than cancer, pneumoconiosis, accident, or suicide were matched by age to the cases. Information that included occupational and smoking history was obtained by interviews with the families of the 96 cases and 86 controls. Major results were as follows: a) The relative risks of lung cancer associated with asbestos exposure and suspected exposure were 2.41 (p less than 0.05) and 1.56, respectively, after controlling for age and smoking history, and the relative risk associated with smoking was 6.01 (p less than 0.05) after adjusting for age and asbestos exposure. b) The age- and smoking-adjusted relative risks of lung cancer associated with asbestos exposure were 3.40 (p less than 0.01) and 1.72 for Kreyberg groups I and II, respectively. Significantly elevated relative risk associated with smoking history was demonstrated for Kreyberg group I, but not for group II, after controlling for age and asbestos exposure.

Molecular basis of beta-thalassemia in Japan: heterogeneity and origins of mutations.

Characterization of beta-thalassemia mutations was attempted for 13 unrelated Japanese patients heterozygous for beta-thalassemia. We have systematically analyzed beta-thalassemia genes using polymerase-chain-reaction-related techniques; dot blot hybridization with oligonucleotide probes complementary to known mutations, restriction endonuclease assay and direct sequencing of amplified genomic DNA. Seven different mutations were detected. Six of them are an amber mutation in codon 90 (GAG to TAG), a four-base-pair deletion in codons 41 and 42 causing premature termination due to frameshift, a C-T substitution at position 654 of IVS-2, a G-A substitution at position 1 of IVS-2 and a C-G substitution at position 848 of IVS-2, leading to splicing defects, and an ocher mutation (GAA-TAA) in codon 121 causing a thalassemia intermedia phenotype with inclusion body formation in erythrocytes. A silent mutation (CTG-TTG) was also detected in codon 91 of the allele with the IVS-2 position 1 mutation. These mutations have been reported previously in the Japanese population. The other mutation is a novel one in the Japanese, an amber mutation (TGG-TAG) in codon 15, causing a beta zero-thalassemia phenotype by premature termination of the beta-globin chain synthesis. We analyzed haplotypes of chromosomes bearing each beta-thalassemia mutation. Origins and a spectrum of mutations in comparison with those detected in malaria-endemic regions are discussed.

Screening of blood donors for human parvovirus B19 and characterization of the results.

BACKGROUND AND OBJECTIVES: Human parvovirus B19 (B19 virus) can be transmitted through blood transfusion and plasma-derived products. In a previous report, we utilized the simple hemagglutination method based on the interaction between the B19 virus and P antigen on human erythrocytes in order to screen the blood donors. We called this method receptor-mediated hemagglutination (RHA) [Lancet 1995;346:1237-1238]. In this paper, we report on a large-scale screening of the B19 virus by RHA and discuss the results. MATERIALS AND METHODS: Donor sera from September 1995 to March 1997 and seroconversion panels were enrolled. Donor sera were examined by RHA for large-scale screening. The positive sera in the first screening were then further investigated by the RHA inhibition test, countercurrent immunoelectrophoresis (CIE), an enzyme-linked immunosorbent assay, and polymerase chain reaction (PCR). We also evaluated the infectivity and neutralizing activity of various kinds of sera by the erythroid colony forming unit (CFU-e) assay. To examine the detection limits of the B19 virus by RHA, B19-viremic sera were purified by sucrose gradient ultracentrifugation. RESULTS: Among 257,710 sera specimens, 293 sera (0.11%) gave a positive reaction in the first screening using RHA. Out of these 293 sera specimens, 31 were positive for PCR, of which 28 were also RHA inhibition-positive, and 25 of the 28 CIE-positive. In the CFU-e injury assay, all the RHA inhibition (+) sera showed a decrease in the number of erythroid colonies. The RHA inhibition (-) PCR (+) B19 antibody (+) sera did not affect the erythroid colony formation and protected CFU-e from injury by the B19 virus. By measuring the amount of purified B19 protein and its RHA titer, the detection limit of the B19 virus by RHA was calculated to the 0.37+/-0.03 ng/ml. CONCLUSION: These results suggest that the RHA(+) RHA inhibition (+) sera were infectious in vitro. The combination of RHA and the RHA inhibition test is considered to be useful for the large-scale screening of infectious B19 virus in blood donors with high specificity.

Acidentes do trabalho por animais peçonhentos / Occupational accidents by poisonous animals

Os autores analisaram 2757 prontuários do Hospital Vital Brazil relativos aos atendimentos feitos durante o ano de 1983. Foram encontrados 561 casos de ofidismo (20,3% dos atendimentos), 1136 casos de araneísmo (41,2%) e 390 casos de escorpionismo (14,1%). Os restantes (24,4%) foram atendimentos de picadas de abelhas, outros insetos, dermatites por taturanas etc. Dos 561 casos de ofidismo, 247 foram por Bothrops (44%), 19 por Crotalus (3,4%), 1 por Micrurus (0,2%), 294 por serpentes näo peçonhentas e/ou näo picadas (52,3%). Dos casos de ofidismo, 64,1% eram maiores de 18 anos e destes , 77% do sexo masculino. Os autores chamam a atençäo para os casos de acidentes do trabalho: 135 casos, o que representa 24% e registram acidentes ocorridos em menores de idade: 10,4%. É feita uma descriçäo das ocupaçöes mais atingidas, estando os lavradores em primeiro lugar. Foram encontrados 1136 casos de araneísmo (41,2%), 680 casos foram picados por Phoneutria (59,8%), 62 casos por Loxosceles (5,4%), 134 por Lycosa (11,9%), 35 casos por outras aranhas (3,1%) e 225 (19,8%) por araneísmo provável. Dos casos de araneísmo, 780 foram em adultos (68,7%) e destes, 459 do sexo masculino (58,8%). Foram caracterizados 131 casos de acidentes do trabalho (11,5%), sendo que 6 ocorreram em menores de idade. As atividades de maior risco foram a lavoura, o manuseio e comércio de bananas e a construçäo civil. Dos 390 casos de escorpionismo, 69,3% ocorreram em adultos e destes, 62,7% do sexo masculino. Foram caracterizados 48 casos de acidentes do trabalho, que representam 12,3%, sendo que 5 atingiram menores de idade (8,6%). A atividade de maior risco foi a construçäo civil