Methyl Mercury Exposure at Niigata, Japan: Results of Neurological Examinations of 103 Adults

Background. Large-scale poisonings caused by methyl mercury (MeHg) have occurred in Japan (Minamata in the 1950s and Niigata in the 1960s) and Iraq (in the 1970s). The current WHO neurological risk standard for adult exposure (hair level: 50 μg/g) was based partly on evidence from Niigata which did not consider any cases who were diagnosed later and/or exposed to low level of MeHg (hair mercury level less than 50 μg/g). Methods. Early in the Niigata epidemic in June 1965 there were two extensive surveys. From these two surveys, we examined 103 adults with hair mercury measurement who consulted two medical institutions. We compared the prevalence and the distribution of neurological signs related to MeHg poisoning between exposure categories. Result. We found 48 subjects with neurological signs related to MeHg poisoning who had hair mercury concentration less than 50 μg/g. Among the neurological signs, sensory disturbance of the bilateral distal extremities was observed more frequently, followed by disequilibrium, hearing impairment, and ataxia, in groups with hair MeHg concentration both below 50 μg/g and over 50 μg/g. Conclusion. The present study suggests the possibility that exposure to MeHg at levels below the current WHO limits could cause neurologic signs, in particular, sensory disturbance

Effects of a Fall Prevention Program on Physical Abilities of Elderly People Living in a Rural Region: an Intervention Trial

本研究の目的は、農村部在宅高齢者を介入群と対照群に分け、筋力向上運動、バランス向上運動を主とした運動プログラムの効果を両群間で比較検証することである。新潟県加治川村における60歳以上の在宅自立高齢者52名を年齢でマッチングして介入群29名、対照群23名の2群に無作為に分けた。6ヶ月後に再調査できた介入群25名、対照群18名の計43名(82.7%)について比較した。介入群には、筋力向上運動、バランス向上運動を中核とした7種目の運動と歩行運動(散歩)を実施した。対照群には、月1回のレクリェーションを行った。調査は、介入前の調査・測定、介入の実施、介入後の調査・測定の流れで行った。その結果、介入群の10m全力歩行の分速・歩幅、膝伸展筋力トルク値、対照群の最大1歩幅左側、10m全力歩行の分速・歩幅・歩行率、膝伸展筋力トルク値が有意に改善した。ただし、転倒、社会生活及び疾病のアンケート調査では両群間に有意差は認められなかった。介入群、対照群がともに改善したことによって、運動プログラムの効果を明確にできなかった。今後、効果を明確に検証するためには、(1)参加者の抽出方法、(2)参加地域を日常的に交流のない地域にする、(3)対象者数を増やす、(4)運動負荷量の把握、といった課題があげられた。The purpose of the present study is to evaluate the effects of a fall prevention program on the physical abilities of elderly people in a rural area by comparing muscular strength and balance before and after an exercise program. The subjects were 52 elderly (above 60 years) residents Kajikawa village, Niigata prefecture, Japan, who lived at home. They were divided randomly into an intervention group of 29 and a control group of 23 persons. The intervention group underwent a training program of seven items of physical activity and walking movements including muscular strengthening and balance improvement, while the control group had a recreational activity once every month. After six months, the intervention group of 25 persons and the control group of 18 persons were available for analysis. The data were obtained from surveys taken before and after the intervention and measured the change during this period. Significant improvements were observed in the speed of full-powered walking for 10 meters, step length, walking ratio, and torque of knee extension muscles in the intervention group, but some improvements were observed also in the control group. From the survey, we were unable to detect any difference between groups in the frequency of falls, mode of social life, or occurrence of disease. Since both groups showed various similar improvements, the effects of the physical intervention program remain unclear. Our future studies should be concerned with (1) the selection methods of participants, (2) choice of independent regions for an intervention group and a control group to minimize intermingling (3) the number of participants, and (4) clear measurements of the physical loads in the exercise

Methyl Mercury Exposure at Niigata, Japan : Results of Neurological Examinations of 103 Adults

Background. Large-scale poisonings caused by methyl mercury (MeHg) have occurred in Japan (Minamata in the 1950s and Niigata in the 1960s) and Iraq (in the 1970s). The current WHO neurological risk standard for adult exposure (hair level: 50 μg/g) was based partly on evidence from Niigata which did not consider any cases who were diagnosed later and/or exposed to low level of MeHg (hair mercury level less than 50 μg/g). Methods. Early in the Niigata epidemic in June 1965 there were two extensive surveys. From these two surveys, we examined 103 adults with hair mercury measurement who consulted two medical institutions. We compared the prevalence and the distribution of neurological signs related to MeHg poisoning between exposure categories. Result. We found 48 subjects with neurological signs related to MeHg poisoning who had hair mercury concentration less than 50 μg/g. Among the neurological signs, sensory disturbance of the bilateral distal extremities was observed more frequently, followed by disequilibrium, hearing impairment, and ataxia, in groups with hair MeHg concentration both below 50 μg/g and over 50 μg/g. Conclusion. The present study suggests the possibility that exposure to MeHg at levels below the current WHO limits could cause neurologic signs, in particular, sensory disturbance

Genetic changes of p53, K-ras, and microsatellite instability in gallbladder carcinoma in high-incidence areas of Japan and Hungary

AIM: To disclose geographic differences in genetic changes involved in gallbladder carcinogenesis between two distinct high-incidence areas of Japan and Hungary.\nMETHODS: We examined 42 cases of gallbladder\ncarcinoma: 22 Japanese and 20 Hungarian cases. p53 mutations at exons 5 to 8 and K-ras mutations at codon 12 were tested by direct sequencing. Microsatellite instability was determined from fluorescent dye-labeled\nPCR amplifications of five-microsatellite markers (BAT-25 , BAT-26 , D2S123, D5S346, and D17S250).\nRESULTS: Mutations of p53 were detected in 11 of 22 Japanese cases and 6 of 18 Hungarian cases (11/22 vs 6/18, P = 0.348). Transition at CpG sites was found in none of 11 Japanese cases and 2 of 6 Hungarian cases;\nthe difference was marginally significant (0/11 vs 2/6, P = 0.110). K-ras mutations were detected in only one of the Hungarian cases. Eight of 19 (42.1%) Japanese cases were MSI-high (presence of novel peaks in more than one of the five loci analyzed), whereas only 1 of 15 (6.7%) Hungarian cases was MSI-high (P = 0.047).\nCONCLUSION: It appears that the p53 mutations and MSI differ in patients with gallbladder carcinoma between two distinct high-incidence areas. Geographic variation might exist in the process of gallbladder carcinogenesis

Endocrine disrupting chemicals in Hungarian canned foods

The aim of this study was to clarify the worldwide residual levels of organochloride compounds, such as BHC and DDT, which were reportedly concentrated in animal tissues by biological food chains. As a part of the investigation of endocrine disrupting chemicals (EDCs), we had a chance to measure the level of these compounds in Hungarian canned foods

Genetic changes of p53, K-ras, and microsatellite instability in gallbladder carcinoma in high-incidence areas of Japan and Hungary

AIM: To disclose geographic differences in genetic changes involved in gallbladder carcinogenesis between two distinct high-incidence areas of Japan and Hungary