Epidemiological study of chromium platers in Japan

A cohort study on platers in Tokyo was carried out using the records of the Tokyo Health Insurance Society of Plating Industry. The type of work and chromium-exposure history of each member of this society was investigated by a questionnaire sent to the manager of each factory. The recovery rate of the questionnaire was 70.5%. Survival information on retired subjects was obtained from the offices of Japanese family registration system (“koseki”). As the result, among 889 male chromium platers who were followed up from April 1, 1970 to September 30, 1976, 19 deaths were observed, but there were no cases of lung cancer. The observed number of deaths was only 50% of the expected number, which had been calculated using the annual male mortality by age of Tokyo. In contrast, a slightly higher number of deaths than expected (107%) was observed in the control group consisting of workers selected from the same factories as the chromium platers. Two types of possible error were considered in this study: the first is that deaths from the chromium-exposed group had been incorrectly assigned to the control group, and the second is that the 30% of nonresponders included a significant number of factories where chromium-related deaths had occurred. However, the response for surviving cases on the history of chromium handling is considered to be reliable. Thus it was decided to conduct a further study focusing on those workers alive on October 1, 1976.     

Uncertainty in cancer risk at low doses of inorganic arsenic

It is unknown whether inorganic arsenic in drinking water concentrations at the current maximum contaminant level of 50 μg/1 poses a cancer risk in the United States. Data from two large epidemiological studies of cancer and arsenic in drinking water in Taiwan indicate a dose‐response relationship, but the magnitude of risk at low concentrations is highly uncertain. Four sources of uncertainty are described: model choice, data aggregation, intra‐village variability of arsenic in well water, arsenic intake from food. New data from an appropriately designed epidemiological study are needed to improve dose‐response assessment.     

Diversity and Geographical Distribution of Phytoplasmas infecting China-tree in Argentina

Yellows diseases associated with phytoplasmas cause high mortality in China‐tree (Melia azedarach) in Argentina, but there has been no previous large‐scale survey to determine their diversity and geographical distribution. To assess the presence and identity of phytoplasmas affecting this species throughout the country, 425 samples of symptomatic trees collected at different geographic locations were analysed by a polymerase chain reaction (using universal and group‐specific primers) and restriction fragment length polymorphism. Phytoplasmas belonging to 16SrIII‐B group were detected at almost every location sampled, whereas 16SrXIII‐C group phytoplasmas, reported for the first time in Argentina, were only found in two regions sharing similar agro‐ecological characteristics (Northeast provinces and Tucumán). Double infections with 16SrIII‐B and 16SrXIII‐C group phytoplasmas were also recorded. Nucleotide sequencing of the 16S rDNA of three Argentinian 16SrXIII‐C group phytoplasma isolates revealed high identity (99.6–99.3%) with the CbY1 isolate reported from Bolivia.     

糖尿病流行病学研究策略及分子遗传学研究进展

流行病学是现代医学的一门重要的基础学科,也是一门应用广泛的应用学科。流行病学作为方法学在复杂疾病研究中有不可替代的作用。糖尿病具有复杂疾病属性,应该以系统的多层次的流行病学方法为研究策略。本文从流行病学与临床医学、遗传学及分子生物学交叉所形成的分支学科一临床流行病学、遗传流行病学及分子流行病学三个方面对糖尿病的研究进展作一综述,并从分子遗传学角度列举了部分糖尿病的候选基因。提出糖尿病的研究应该从宏观流行病学（如社会环境等因素的影响）和微观流行病学（如分子遗传等）结合系统地进行研究。     

糖尿病流行病学研究策略及分子遗传学研究进展

流行病学是现代医学的一门重要的基础学科,也是一门应用广泛的应用学科。流行病学作为方法学在复杂疾病研究中有不可替代的作用。糖尿病具有复杂疾病属性,应该以系统的多层次的流行病学方法为研究策略。本文从流行病学与临床医学、遗传学及分子生物学交叉所形成的分支学科--临床流行病学、遗传流行病学及分子流行病学三个方面对糖尿病的研究进展作一综述,并从分子遗传学角度列举了部分糖尿病的候选基因。提出糖尿病的研究应该从宏观流行病学(如社会环境等因素的影响)和微观流行病学(如分子遗传等)结合系统地进行研究。     

Epidemiological survey of Giardia spp. and Blastocystis hominis in an Argentinian rural community

The aim of this study was to relate personal data, socio-cultural and environmental characteristics, and the presence of symptoms/signs with the frequencies of Giardia spp. and Blastocystis hominis among a rural population in Buenos Aires Province, Argentina. Of the surveyed population (350), 3.7% were infected with only Giardia spp. or 22.9% with B. hominis, and 2.3% were infected with both protozoa. The frequency of infection according to sex; 6.1% of males were infected and 1.6% of females by Giardia spp., 26.7% and 19.5% by B. hominis, and 2.4% and 2.2% by both parasites, respectively. Giardia spp. was detected in only three adults (over 14 years), but B. hominis was more frequent in adults than in children. The prevalences of these protozoa in this community are lower than those reported by other Argentinean studies, which is probably associated with the low density of the studied population (5.95 inhab/km2). Statistical analysis revealed that a male sex, flooding of the home, the use of a latrine, and an abdominal pain were correlated with the presence of these parasites, which indicate the importance of these factors in rural communities.     

2017–2022年中国口蹄疫流行状况分析

【目的】分析近年来中国口蹄疫流行和传播特点,研判口蹄疫流行趋势。【方法】以2017-2022年间中国报告发生的口蹄疫疫情为研究对象,从疫情的“三间分布”、生产环节分布、流行毒株分子流行病学分析及溯源等方面,对近6年的疫情情况进行系统梳理。【结果】2017-2022年间中国共有15个省份报告发生口蹄疫疫情54次。总体形势稳定：Asia 1型口蹄疫维持无疫状态;2019-2022年连续4年未发生A型口蹄疫疫情;田间以散发O型口蹄疫为主。六年间报告牛口蹄疫疫情36次,羊疫情1次,猪疫情17次。分子流行病学研究表明,O/Mya-98、O/Ind-2001、O/CATHAY、O/PanAsia和A/Sea-97这5个流行毒株同时流行,且与同时期周边国家（缅甸、老挝和越南等）口蹄疫毒株遗传关系密切。流行病学调查结果显示,疫情（尤其是牛疫情,占比66.7%）主要发生在流通（57%）、散养（32%）等免疫薄弱环节。【结论】对内强化疫苗免疫和流通动物管控,对外严防境外毒株传入仍是今后中国口蹄疫防控的重要任务。     

In utero arsenic exposure and epigenome-wide associations in placenta,umbilical artery,and human umbilical vein endothelial cells

Exposure to arsenic early in life has been associated with increased risk of several chronic diseases and is believed to alter epigenetic programming in utero. In the present study, we evaluate the epigenome-wide association of arsenic exposure in utero and DNA methylation in placenta (n = 37), umbilical artery (n = 45) and human umbilical vein endothelial cells (HUVEC) (n = 52) in a birth cohort using the Infinium HumanMethylation450 BeadChip array. Unadjusted and cell mixture adjusted associations for each tissue were examined along with enrichment analyses relative to CpG island location and omnibus permutation tests of association among biological pathways. One CpG in artery (cg26587014) and 4 CpGs in placenta (cg12825509; cg20554753; cg23439277; cg21055948) reached a Bonferroni adjusted level of significance. Several CpGs were differentially methylated in artery and placenta when controlling the false discovery rate (q-value<0.05), but none in HUVEC. Enrichment of hypomethylated CpG islands was observed for artery while hypermethylation of open sea regions were present in placenta relative to prenatal arsenic exposure. The melanogenesis pathway was differentially methylated in artery (Max F P < 0.001), placenta (Max F P < 0.001), and HUVEC (Max F P = 0.02). Similarly, the insulin-signaling pathway was differentially methylated in artery (Max F P = 0.02), placenta (Max F P = 0.02), and HUVEC (Max F P = 0.02). Our results show that prenatal arsenic exposure can alter DNA methylation in artery and placenta but not in HUVEC. Further studies are needed to determine if these alterations in DNA methylation mediate the effect of prenatal arsenic exposure and health outcomes later in life.     

Epidemiological reasoning and biological rationale

Abstract

Studies in which the use of biomarkers resub in faulty epidemiological reasoning are reviewed. The criteria for causal associations in science are discussed.     

Magnesium (and trace substance) deficiencies in the pathogenesis of cancer

Except for a few experimental models of magnesium (Mg)-deficiency-induced neoplasms, less attention has been paid in the past quarter century in the Western world to this macromineral than to the trace elements; e.g., selenium (Se) and zinc (Zn), and to vitamins, deficiencies of which are each considered probable factors in oncogenesis. Although early epidemiologic studies showed an inverse correlation between the amount of Mg in soil and water and the incidence of (gastric) cancer, and several animal studies supported the premise that Mg has a prophylactic effect against induction of cancer, other studies showed that Mg supplementation increased the growth of established experimental tumors. Thus, enthusiasm for this approach subsided. The early epidemiologic findings have since been confirmed, and there have been studies demonstrating the importance of Mg in maintaining immunocompetence, and others indicating that immunodeficiencies increase susceptibility to the development of cancer. Evidence has now accrued that indicates that Mg deficiency increases susceptibility to chemical oncogens. The abnormal metabolism of tryptophan (yielding a carcinogenic metabolite) that indicates functional or absolute pyridoxine deficiency is an indirect clue to Mg deficiency. Vitamin B₆-activated enzymes require Mg as a cofactor. However, the early warnings against the use of Mg as part of an antineoplastic program against established cancer were justified, since rapidly metabolizing cells (such as cancers) are dependent on Mg. There are similarities between experiences with Mg and with Se and Zn. All three are required for normal metabolism; Se also protects against free radicals in the environment. Mg and Zn have increased established tumor growth, and their depletion has been applied to antineoplastic programs, with risks comparable to those of using antimetabolic agents.     

Phytoremediation of arsenic contaminated soil by Pteris vittata L. II. Effect on arsenic uptake and rice yield

A greenhouse experiment evaluated the effect of phytoextraction of arsenic from a contaminated soil by Chinese Brake Fern (Pteris vittata L.) and its subsequent effects on growth and uptake of arsenic by rice (Oryza sativa L.) crop. Pteris vittata was grown for one or two growing cycles of four months each with two phosphate sources, using single super phosphate (SSP) and di-ammonium phosphate (DAP). Rice was grown on phytoextracted soils followed by measurements of biomass yield (grain, straw, and root), arsenic concentration and, uptake by individual plant parts. The biomass yield (grain, straw and rice) of rice was highest in soil phytoextracted with Pteris vittata grown for two cycles and fertilized with diammonium phosphate (DAP). Total arsenic uptake in contaminated soil ranged from 8.2 to 16.9 mg pot(-1) in first growing cycle and 5.5 to 12.0 mg pot(-1) in second growing cycle of Pteris vittata. There was thus a mean reduction of 52% in arsenic content of rice grain after two growing cycle of Pteris vittata and 29% after the one growing cycle. The phytoextraction of arsenic contaminated soil by Pteris vittata was beneficial for growing rice resulted in decreased arsenic content in rice grain of <1 ppm. There was a mean improvement in rice grain yield 14% after two growing cycle and 8% after the one growing cycle of brake fern.     

Magnesium,calcium, copper,and zinc in meals

Meals of 12 diets were prepared from conventional foods with precautions against contamination by metallic elements because of epidemiologic associations between ischemic heart disease and the metabolism of magnesium, calcium, copper, and zinc. Magnesium, calcium, copper, and zinc were measured by atomic absorption spectrometry with satisfactory accuracy and precision. The mean daily amount of copper in the diets was less than the apparent adult requirement. Mean amounts of magnesium and zinc were close to apparent requirements; however, adults consuming amounts less than one standard deviation below these means may be depleting body stores and be at risk of pathology. Magnesium and copper were highly correlated (r=0.849,P=0.0001) in meals. This and other significant correlations probably will prevent the relationships of these elements to ischemic heart disease from being elucidated by epidemiology. Metabolic experiments will be necessary to differentiate among several hypotheses.     

Prevalence and Comparison of Diagnostic Methods for Trichomonas vaginalis Infection in Pregnant Women in Argentina

The objectives of this study were to conduct a prevalence survey of trichomoniasis in pregnant women and to evaluate the utility of different methods for its diagnosis. A total of 597 vaginal exudates from pregnant women who were examined at the Hospital de Clinicas in Buenos Aires, Argentina from 1 August 2005 to 31 January 2007, were prospectively and consecutively evaluated. The investigation of Trichomonas vaginalis was made by different microscopic examinations, and culture on liquid medium. The sensitivity and specificity of the microscopic examinations were assessed considering culture on liquid medium as the "gold standard". The prevalence of T. vaginalis obtained by culture on liquid medium was 4.0% (24/597). The prevalence of T. vaginalis obtained by direct wet smear, prolonged May-Grunwald Giemsa staining, and sodium acetate-formalin (SAF)/methylene blue staining-fixing technique was 1.8%, 2.3% and 2.5%, respectively. The sensitivity of the direct wet smear was 45.8%, that of the prolonged May-Grunwald Giemsa staining was 58.3%, and that of the SAF/methylene blue method was 62.5%. Considering the 3 microscopic examinations altogether, the sensitivity rose to 66.7% and the specificity was 100% for all of them. This is the first time that the prevalence data of T. vaginalis by culture in pregnant women are published in Argentina. Due to the low sensitivity obtained by microscopy in asymptomatic pregnant women, the use of the liquid medium is recommended during pregnancy, in order to provide an early diagnosis and treatment.     

Interaction between humic substances and carbohydrates in a Pampasic pond (Argentina)

Interaction between humic substances from a Pampasic pond and carbohydrates was studied. Determinations were performed by gel chromatography using radiolabeled glucose. The results showed that upon lowering the pH the interaction decreases in relation to the steric arrangement that causes the diminution of the accessibility of the available sites. Results of displacement experiments carried out by addition of unlabeled glucose, galactose, saccharose and starch, confirmed that the interaction occurs mainly through labile non specific bonds and is, to a certain degree, independent of the carbohydrate molecular weight involved. This revised version was published online in July 2006 with corrections to the Cover Date.     

Diagnosis and treatment of lung cancer in Denmark during the COVID-19 pandemic

BackgroundWe examined the number of lung cancers diagnosed, the quality of care and the socio-economic and clinical characteristics among patients with lung cancer during the COVID-19 pandemic compared to previous years.MethodsWe included all patients ≥ 18 years old diagnosed with lung cancer from 01 January 2018 to 31 August 2021 as registered in the Danish Lung Cancer Registry. Using a generalised linear model, we estimated prevalence ratios (PR) and 95% confidence intervals (CI) of the associations between the pandemic and socioeconomic and clinical factors, and indicators of quality.ResultsWe included 18,113 patients with lung cancer (82.0% non-small cell lung cancer (NSCLC)), which was similar to the preceding years, although a decline in NSCLC cases occurred during the first lockdown period in 2020. No difference in distribution of income or educational level was observed. No difference was observed in the quality of treatment – as measured by curative intent, proportion of patients resected or who died within 90 days of diagnosis.ConclusionUsing nationwide population-based data, our study reassuringly shows no adverse effects of the COVID-19 pandemic on the diagnosis, socio-economic characteristics nor quality of treatment of lung cancer, as compared to the preceding years.     

Chromium,nickel, and arsenic determinations in human samples by thermal and epithermal neutron activation analyses

Both thermal and epithermal neutron activation analyses have been employed to determine chromium and nickel in lung tissue and arsenic in urine. Based on accuracy, precision, and detection limits, these techniques have been successfully used to analyze lung tissue from a deceased welder, who died, from cancer, and to paratake in an interlaboratory toxicological urine program.     

微生物耐砷机理及其在砷地球化学循环中的作用北大核心CSCD

砷是一种无处不在的有毒类金属,其强致癌性引起了人类的广泛关注。在自然环境中,砷的转化存在物理化学过程和生物过程,其中微生物介导的砷转化是环境砷行为的主要影响因素。微生物的耐砷特性与砷吸收、氧化还原、甲基化、区隔化和外排等过程密切相关。砷在微生物体内的转运转化主要与砷解毒有关,但某些微生物可利用氧化还原过程产生的能量以维持其生长需求。本文综述了微生物介导的砷吸收、转化、区隔化和外排机制,这对阐明砷的地球化学循环过程及指导砷污染土壤和水体修复、阻控农作物砷吸收等方面具有重要意义。