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PubMed2006

Predictors of psychological distress in survivors of the 1999 earthquakes in Turkey: effects of relocation after the disaster.

OBJECTIVE: Relocations after disasters are known to cause added distress in survivors. This study examined the effects of migration and other factors on psychological status of survivors 4 years after the two severe earthquakes in Turkey. METHOD: Five hundred and twenty-six adult survivors of the 1999 earthquakes currently living in Ankara were given self-report measures assessing traumatic stress, depression, earthquake experience and social support. RESULTS: The rates of current post-traumatic stress disorder (PTSD) and depression were 25% and 11%, respectively. Although both traumatic stress and depression factors were predicted by some demographic and trauma severity variables, relocation status predicted depression but not traumatic stress. CONCLUSION: The rates of psychological distress were higher than expected in a city considered to be safe in terms of earthquake risk. Relocation after the disaster may increase psychological distress by disrupting the social network.

Adolescent↗

PubMed1997

Body mass and 26-year risk of mortality among women who never smoked: findings from the Adventist Mortality Study.

The authors have examined the relation between the Quetelet body mass index (BMI) and 26-year risk of all-cause mortality in a population of 12,576 non-Hispanic while, Seventh-day Adventist women (ages 30-74 years) who never smoked. Mortality risk for each BMI quintile (I, < 21.3 kg/m2; II, 21.3-22.9 kg/m2; III, 23.0-24.8 kg/m2; IV, 24.9-27.4 kg/m2; and V, > 27.4 kg/m2) was determined from a proportional hazard regression with adjustment for age and other covariables. In this population, the overall BMI-mortality relation showed dependence on age, duration of follow-up, and baseline indicators of preexisting illness (weight fluctuation, history of major chronic disease, and severe physical complaints). Therefore, the analysis focused on women with no indicators of preexisting illness, and risk estimates were stratified by age at baseline and duration of follow-up. Among middle-aged women (ages 30-54 years), the authors found a weak linear relation during years 1-8 (median attained age, 51 years), a significant linear relation during years 9-14 (median attained age, 57 years), and a significant nonlinear (U-shaped) relation during years 15-26 (median attained age, 68 years). Among older women (ages 55-74 years), they found a significant nonlinear (U-shaped) relation during years 1-8 (median attained age, 71 years) and significant linear relations during years 9-14 (median attained age, 77 years) and years 15-26 (median attained age, 87 years). These findings implicate overweight as a risk factor for fatal disease among women throughout adulthood and raise the possibility that lean, apparently healthy, middle-aged women may experience a higher risk of death during old age due to their lower body weight.

Adult↗

PubMed2006

[Dynamic monitoring of serum pepsinogen among high risk populations of gastric cancer in Zhuanghe county].

OBJECTIVE: To investigate the dynamic changes of serum pepsinogen (PG) among the high risk populations of gastric cancer. METHODS: Peripheral blood samples were collected from 444 subjects in the high risk areas of gastric cancer in Zhuanghe county, Liaoning province, who underwent screening of gastric cancer, 225 males and 219 females, aged 48.31 (21 - 76). ELISA was used to measure the serum PG I and PG II. The PG I/II ratio was calculated. Gastroscopy was conducted to take 4 pieces of biopsy specimens from each subject to undergo pathological examination. Histological examination and serum Hp-IgG antibody determination by ELISA were performed to detect the infection of Helicobacter pylori (Hp). The above mentioned examinations were carried out at the first screening and 6, 12, and 30 months later during follow-up. RESULTS: (1) In the age group 51 - 60, the percentage change in PG II of 6-month follow-up was 0.84, significantly lower than those of the 12-month follow-up (1.22, P = 0.019) and 30-month follow-up (1.24, P = 0.004), and the percentage change in PG I/II of the 6-month follow-up was 1.09, significantly higher than those of the 12-month follow-up (0.75, P = 0.027) and 30-month follow-up (0.69, P = 0.001). However, there were no significant differences in serum PG I, serum PG II, and PG I/II ratio in other age groups. (2) The percentage change in serum PG I of the patients of superficial gastritis (SG) with mitigation of the 6-month follow-up was 0.69, significantly lower than that of the 12-month follow-up (0.97, P = 0.002). The percentage change in PG I/II of the patients of atrophic gastritis (AG) with mitigation of the 6-month follow-up was 1.13, significantly higher than that of the 12-month follow-up (0.75, P = 0.042). (3) The percentage change in PG I of the SG-->NOR (normal) group was 0.94, significantly higher than that of the SG-->AG group (0.79, P = 0.002). The percentage changes in PG I and PG II of the AG-->NOR group were 0.43 and 0.60 respectively, both significantly lower than those of the AG-->SG group (0.87, P = 0.000, and 1.11, P = 0.010). (4) The percentage change in PG I of the Hp negative-->Hp positive group was 0.94, significantly higher than that of the Hp negative-->Hp negative group (0.81, P = 0.026). The percentage changes in PG I and PG II of the Hp positive-->Hp negative group were 0.74 and 0.86 respectively, both significantly lower than those of Hp positive-->Hp positive group (0.93 and 1.15 respectively, both P = 0.000), and the percentage change in PG I/II of the Hp positive-->Hp negative group was 0.90, significantly higher than that of the Hp positive-->Hp positive group (0.70, P = 0.022). CONCLUSION: The percentage change of serum PG is correlated with time of follow-up, feature of stomach disease, and status of Hp infection. Dynamic detection of serum PG can be applied in monitoring the populations in high risk area of gastric cancer.

Adult↗

PubMed1976

Child health clincs and inverse care laws: evidence from longitudinal study of 1878 pre-school children.

In a longitudinal study it was intended that 1878 children should receive periodic developmental examinations from the age of 6 weeks to 3 years. The children were divided into those with a high or low risk of developmental problems. Although clinic attendance rate of 85-89% were achieved in the catchment area 100% coverage was difficult because of population mobility and non-attendance at clinics. Children in families who moved away from the area were more difficult to trace and thus more likely to miss developmental examinations. This was a greater problem in the high-risk group. Altogether 683 home developmental examinations were carried out on 269 children who did not attend clinics. Thirty-five per cent of these children were in the high-risk group compared with 22% in the study population, and significantly more had developmental problems. Thus one possible way of reaching and helping such children is though home developmental examinations.

Child Development↗

PubMed2001

Is German long-term care insurance a model for the United States?

German long-term care insurance, implemented in 1995, significantly extends the coverage of care-related risks. Given the similarities of German and U.S. institutional features, the German social insurance approach has been put forward as a possible model for long-term care in the United States. Using a political economy framework, the authors conducted a policy analysis that compares the main shortfalls of long-term care (LTC) provision in the United States and Germany, examines the responses provided by LTC insurance in Germany, and relates them to broader trends and proposals for change in welfare policy in both countries. German LTC insurance includes a high degree of consumer direction and compensation and protection for informal caregivers; it supports the extension of community-based services. Its shortfalls include the continued split between health and LTC insurance. In both countries, decentralization and institutional and financial fragmentation are some of the characteristics responsible for the failure to promote egalitarian social policy and substantially expand social protection to family- and care-related risks. The German LTC program is a good model for the United States. With a social insurance approach to LTC, costs are spread across the largest possible risk pool. Major goals that can be reached with such a program include establishment of universal entitlements to LTC benefits, consumer choice, and equitability and uniformity.

Activities of Daily Living↗

PubMed2004

A field methodology to study effects of UV radiation on fish larvae.

There is a considerable lack of in situ specific information about the effects of UV-B radiation on limnic animals studied in the field. We exposed larval pike (Esox lucius L.) in two types of cuvettes (glass and quartz) placed at different depths (5 or 15 cm) to natural solar UV or to artificially enhanced UV-B (lamps on 3 h per day), simulating the scenarios for coming decades. Dose realism and comparability with earlier laboratory experiments was the main purpose, and therefore UV-B irradiances to the surface as well as underwater irradiances were directly measured. Result showed that UV-B dose rates in natural waters are low even though DOC concentration was low (4.8 mg/l) in our study lake. A slight increase in ambient UV-B dose rates was enough to cause neurobehavioral symptoms in pike larvae. However, the dose rates applied were inadequate to affect superoxide dismutase (SOD) or HSP70. While assessing the suggested risks due to increased UV, conclusions emphasize the importance of conducting field UV studies as supplements to laboratory experiments. We also recommend direct measurements of UV-radiation at sites where the target organisms are actually exposed.

Animals↗

PubMed2007

A nonlinear model for assessing multiple probabilistic risks: a case study in South five-island of Changdao National Nature Reserve in China.

Several methods for estimating the potential impacts caused by multiple probabilistic risks have been suggested. These existing methods mostly rely on the weight sum algorithm to address the need for integrated risk assessment. This paper develops a nonlinear model to perform such an assessment. The joint probability algorithm has been applied to the model development. An application of the developed model in South five-island of Changdao National Nature Reserve, China, combining remote sensing data and a GIS technique, provides a reasonable risk assessment. Based on the case study, we discuss the feasibility of the model. We propose that the model has the potential for use in identifying the regional primary stressor, investigating the most vulnerable habitat, and assessing the integrated impact of multiple stressors.

China↗

PubMed1996

Oral contraceptives and cancer. A review of the evidence.

The following review considers epidemiological data published from 1990 onwards on oral contraceptives (OCs) and the risk of cancers of the breast, cervix uteri, endometrium, ovary, liver and skin. In several studies, breast cancer risk was seen to be elevated among women who were current users of an OC, or had recently stopped using an OC, whereas there was no residual risk 5 or more years after stopping OC use. No interaction was observed between type of OC, or with any recognised risk factor for breast cancer, or time-factor, except for some potential excess risk for women who started OC use at a young age. Most studies have confirmed that OCs moderately increase the risk of cervical cancer, particularly in human papilloma virus (HPV)-positive women, thus suggesting that OCs may act as a promoter for HPV-induced carcinogenesis. Recent epidemiological studies have confirmed that combined OCs provide substantial protection against endometrial and ovarian cancers, and results suggest that such protection is long-lasting, and may persist for 15 years or more after stopping OC use. Most case-control studies have shown a relationship between OC use and hepatocellular carcinoma. However, data from cohort studies or analysis of vital statistics indicate that the public health impact of such an association is modest, if not negligible. No association was observed between combined OC use and the incidence of skin melanoma, or any other common skin neoplasm. In terms of clinical and public health implications, the most relevant points regarding OC use are: (i) recent data confirm that OCs confer presistent protection against ovarian cancer; and (ii) any increased risk of breast cancer in OC users is moderate and is restricted to current/recent users. This is reassuring for younger women, whose baseline risk of this disease is extremely low.

Contraceptives, Oral, Hormonal↗

PubMed2004

Community ecology of small mammal populations in Panamá following an outbreak of Hantavirus pulmonary syndrome.

In late 1999 and early 2000, an outbreak of hantavirus pulmonary syndrome (HPS) occurred in and around Los Santos, on the Azuero Peninsula of southwestern Panamá. This HPS episode, resulting in 22% case fatality, was linked to the Costa Rican pigmy rice rat, Oligoryzomys fulvescens costaricensis, which harbored a then undescribed hantavirus, Choclo virus. In addition, Cherrie's cane rat, Zygodontomys brevicauda cherriei, was identified as carrying a distinct hantavirus, Calabazo virus with no known pathogenicity to humans. Herein we present the ecological results of the outbreak investigations in the Azuero region. A total of 164 animals were captured, of which 126 were potential small, non-volant mammal hosts of a hantavirus: rodents in the family Muridae. There were significant differences in small mammal community structure between case sites and a negative control site. Differences were manifest in ecological measures of species diversity and in species evenness and heterogeneity measures, as indicated by Pairwise Euclidian distances and Morisita indices of community similarity. Our analyses suggest that human activities (i.e., deforestation for cattle ranching) coupled with environmental factors (i.e., increased precipitation) may have synergistically coalesced for an increased risk of HPS to area residents.

Animal Husbandry↗

PubMed2002

Defining "adverse environmental impact" and making paragraph 316(b) decisions: a fisheries management approach.

The electric utility industry has developed an approach for decisionmaking that includes a definition of Adverse Environmental Impact (AEI) and an implementation process. The definition of AEI is based on lessons from fishery management science and analysis of the statutory term "adverse environmental impact" and is consistent with current natural resource management policy. The industry has proposed a definition focusing on "unacceptable risk to the population"s ability to sustain itself, to support reasonably anticipated commercial or recreational harvests, or to perform its normal ecological function." This definition focuses not on counting individual fish or eggs cropped by the various uses of a water body, but on preserving populations of aquatic organisms and their functions in the aquatic community. The definition recognizes that assessment of AEI should be site-specific and requires both a biological decision and a balancing of diverse societal values. The industry believes that the definition of AEI should be implemented in a process that will maximize the overall societal benefit of the paragraph 316(b) decision by considering the facility"s physical location, design, and operation, as well as the local biology. The approach considers effects on affected fish and shellfish populations and the benefits of any necessary best technology available (BTA) alternatives. This is accomplished through consideration of population impacts, which conversely allows consideration of the benefits of any necessary BTA modifications. This in turn allows selection of BTAs that will protect potentially affected populations in a cost-effective manner. The process also employs risk assessment with stakeholder participation, in accordance with EPA's Guidelines for Ecological Risk Assessment. The information and tools are now available to make informed decisions about site-specific impacts that will ensure protection of aquatic ecosystems and best serve the public interest.

Animals↗

PubMed2003

Epidemiologic determinants of aural abscessation in free-living eastern box turtles (Terrapene carolina) in Virginia.

Epidemiologic determinants of 46 cases of aural abscessation in free-living eastern box turtles (Terrapene carolina) admitted to the Wildlife Center of Virginia (Virginia, USA) from 1991 to 2000 were evaluated. County human population density, year and season of admission, weight, and sex did not affect the risk for box turtles to develop aural abscessation. Counties with cases of aural abscessation were not randomly distributed, but rather were clustered into two multi-county regions. Geographic location was the only risk factor associated with aural abscessation in box turtles found in this study. Possible etiologies could include chronic infectious disease, malnutrition, or chronic exposure to environmental contamination with organochlorine compounds.

Abscess↗

PubMed2004

A watershed-scale model for predicting nonpoint pollution risk in North Carolina.

The Southeastern United States is a global center of freshwater biotic diversity, but much of the region's aquatic biodiversity is at risk from stream degradation. Nonpoint pollution sources are responsible for 70% of that degradation, and controlling nonpoint pollution from agriculture, urbanization, and silviculture is considered critical to maintaining water quality and aquatic biodiversity in the Southeast. We used an ecological risk assessment framework to develop vulnerability models that can help policymakers and natural resource managers understand the impact of land cover changes on water quality in North Carolina. Additionally, we determined which landscape characteristics are most closely associated with macroinvertebrate community tolerance of stream degradation, and therefore with lower-quality water. The results will allow managers and policymakers to weigh the risks of management and policy decisions to a given watershed or set of watersheds, including whether streamside buffer protection zones are ecologically effective in achieving water quality standards. Regression analyses revealed that landscape variables explained up to 56.3% of the variability in benthic macroinvertebrate index scores. The resulting vulnerability models indicate that North Carolina watersheds with less forest cover are at most risk for degraded water quality and steam habitat conditions. The importance of forest cover, at both the watershed and riparian zone scale, in predicting macrobenthic invertebrate community assemblage varies by geographic region of the state.

Animals↗

PubMed2000

Comparing risk factors for population extinction.

Extinction risk of natural populations of animals and plants is enhanced by many different processes, including habitat size reduction and toxic chemical exposure. We develop a method to evaluate different risk factors in terms of the decrease in the mean extinction time. We choose a population model with logistic growth, environmental and demographic stochasticities with three parameters (intrinsic growth rate r, carrying capacity K, and environmental noise sigma(2)(e)). The reduction in the habitat size decreases carrying capacity K only, whilst toxic chemical exposure decreases survivorship (or fertility) and in effect reduces both r and K. We derived a formula for the reduction in habitat size that decrease the mean extinction time by the same magnitude as a given level of toxic chemical exposure. In a large population (large K) or in a slowly growing population (small r), a small decrease in survivorship can cause the extinction risk increase corresponding to a significant reduction in the habitat size. This conclusion depends also on the nonlinearity of dose-effect relationship. To illustrate the method, we analyse a freshwater fish, Japanese crucian carp (Carassius auratus subsp.) in Lake Biwa.

Animals↗

PubMedDate not supplied

Behavioural effects of pesticides in bees--their potential for use in risk assessment.

This paper reviews a wide variety of behavioural effects that have been reported in bees following exposure to pesticides, primarily insecticides. These range from effects on odour discrimination in the individual to the loss of foraging bees due to disruption of their homing behaviour. Some of these effects have the potential to have a significant impact on the development and survival of colonies. However, there is currently little guidance available on the types of behavioural data which should be collected during laboratory, semi-field or field regulatory studies or how they should be included and interpreted in risk assessment. Further work is required to allow risk assessment to include significant behavioural effects and their longer term consequences on colony survival and development. Such an approach will require a larger base set of data to predict the longer-term consequences on colonies of short-term effects on individuals, e.g. through population modelling.

Animals↗

PubMed2003

Limitations of current risk characterization methods in probabilistic environmental risk assessment.

In probabilistic environmental risk assessment, the likelihood and the extent of adverse effects occurring in ecological systems because of exposure(s) to substances are estimated. It is based on the comparison of an exposure/environmental concentration distribution, with a species sensitivity distribution derived from toxicity data. The calculation of a probabilistic risk can be performed in many ways (e.g., area under the curve in joint probability curves). However, several (hypothetical) examples and some theoretical considerations illustrate that the current risk characterisation methods have an integrative character and they focus on the statistical comparison of two distributions without properly considering the environmental interpretation of these underlying distributions. Several scenarios with varying exposure/environmental concentration distribution and species sensitivity distribution standard deviations are discussed.

Animals↗

PubMed1985

Plantar pressure measurements and the prevention of ulceration in the diabetic foot.

Static and dynamic measurements of foot pressure have been carried out on three groups of subjects: diabetic patients with neuropathy (with and without a history of ulceration), diabetic patients with no neuropathy, and normal subjects as controls. In many cases both techniques of measurement detected areas of abnormally high pressure under the foot, but in some cases a particularly high-pressure spot was detected on only one of the tests and sometimes both methods were needed to reveal all the areas of the foot which might be considered to be at risk. The dynamic measurements tended to show multiple areas of high pressure better than the static measurements. Our results indicate the importance of making both types of measurement when seeking to devise suitable means of protecting the foot from ulceration.

Diabetes Mellitus↗

PubMed2006

A method of assessing ecological risk to night heron, Nycticorax nycticorax, population persistence from dichlorodiphenyltrichloroethane exposure.

This paper first introduces a probabilistic method for quantitatively evaluating the effects of chemical pollutants in the environment on a wildlife population, which was applied to assess the ecological risk to night heron (Nycticorax nycticorax) population persistence from dichlorodiphenyltrichloroethane (DDE) exposure in Tai Lake, China. Intrinsic rate of population increase (r) calculated with a population age-structured matrix model was used to measure the adverse effect on population. To perform a probabilistic analysis of risk, lost intrinsic rate of population increase (deltaZ) because of DDE exposure was applied to express the exact extent of risk. The result showed that the risk (i.e., the expectancy of deltaZ of the night heron population exposed to DDE in Tai Lake) was 0.0259, indicating a decrease in gross population size of 2.56% every year compared with that of the previous year without DDE exposure.

Animals↗

PubMed1994

[Onchocerciasis control program in West Africa: socioeconomic development and risk of recrudescence of transmission. 2. Experimental study of the transmission of Onchocerca volvulus strains from Southwestern Sierra Leone by Simulium yahense and Simulium squamosum].

The movements of human populations towards the mining wealth of the northern parts of Sierra Leone are favorable to a high contact rate between onchocerciasis patients coming from the south-western area of this country and the vector species Simulium yahense and Simulium squamosum which assume the essential of onchocerciasis transmission in the above-mentioned mining area. In fact, the Onchocerca volvulus strains concerned by this contact seem to be more pathogenic than those locally transmitted. In order to assess the danger it could represent for the Onchocerciasis Control Programme in West Africa, we carried out the experimental study of transmission which may result from this contact when more or less infected onchocerciasis patients are involved. The results indicated that this transmission by S. yahense may reach high proportions only when heavily infected onchocerciasis patients are implicated. We took also notice of the low capacity of S. squamosum to transmit the O. volvulus strains from the south-western Sierra Leone, irrespective of the microfilarial load of patients. Thus, in the most favorable conditions of a high parasite-vector contact of the study, involvement of S. yahense and onchocerciasis patients with high skin microfilarial loads is the only occurrence to which a high risk of intensive transmission may be related. The authors consider that the probability of such a risk occurring will be drastically reduced, due to the considerable decrease of skin microfilarial loads in human communities which regularly have the advantage of ivermectin (Mectizan) mass treatments.

Animals↗