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PubMed2002

[Impact on environmental factors on the reproductive system and fetal development].

A literature review discusses the effect of selected environmental factors on women reproductive system, fetal development and growth. According to recent reports, 2-3% of newborns have congenital malformations. These malformations are caused by interaction of genetic and environmental factors. Exposure of paternal or maternal organisms to environmental hazards may damage germ cells or interfere fetal development, resulting in malformation of various organ systems. Since environmental hazards exposures are complex, it is difficult to establish the primary effect of single factor. Factors, that are known to increase the risk of congenital malformations, preterm delivery or spontaneous abortion, are classified into five groups--psychological, social, biological, physical and chemical factors. The governments of most counties recognize the effect of hazardous environmental factors on public health as global problem. World Health Organization encourages researches, aimed at evaluation of various environmental factors impact on health of pregnant women and their offsprings.

Abnormalities, Drug-Induced↗
PubMed2003

Associations between leptospiral infection and seropositivity in rodents and environmental characteristics in Argentina.

Our objective was to look for associations between leptospiral infection in rodents and selected environmental and rodent characteristics in Santa Fe, Argentina. Rodents (n = 214) were trapped alive from January 1998 to December 1999 in three environmental settings. Kidneys from 118 rodents were cultured and serum samples from 201 were processed by enzyme-linked immunosorbent assay (ELISA). Logistic regression was performed with ELISA seropositivity as the dependent variable and rodent characteristics were offered as independent variables. Overall prevalence of positive ELISA reactions was 42% (84/201). In urban areas, leptospiral isolations belonged to the Ballum serogroup; in natural corridors, they belonged to the Icterohaemorragiae serogroup. M. musculus (house mouse) was the most-frequently captured species and the predominant one in urban areas. Most isolates and seropositivity results were obtained on this species. Adults and subadults had higher seroprevalences than juvenile rodents. Oligoryzomys flavescens had higher seroprevalence than Akodon azarae, Mus musculus, Rattus rattus and Rattus norvegicus.

Animals↗
PubMed1996

Circadian rhythms and cancer chemotherapy.

Temporal coordination of biologic processes with an approximately 24-h cycle (circadian) is common throughout the animal and plant kingdom and even in some prokaryotic organisms. In all organisms studied, the capability to keep biologic time is an inherited characteristic located intracellularly. These biological clocks anticipate and get the organism ready for regular environmental changes. This indicates both the ubiquity and the weight of the selective environmental pressure to keep time accurately. Several molecular strategies for biologic time keeping have apparently arisen independently several times throughout evolution. The anatomic, biochemical, and molecular mechanisms of the clock are in the process of being defined. This temporal organization at the cellular, organ, and organismic levels results in predictable differences in the capacity of plants, animals, and human beings to respond to therapeutic interventions administered at different times throughout important biologic cycles (e.g., circadian timed therapy). In the treatment of the cancer bearing host, circadian timing of surgery, anticancer drugs, radiation therapy, and biologic agents can result in improved toxicity profiles, enhanced tumor control, and improved host survival. The routine clinical application of such principles is facilitated by the availability of programmable drug delivery devices. Rhythm frequency ranges other than 24-h (e.g., low frequency: menstrual; high frequency: 10 to 120 min) may also be important to understanding health and disease and to designing successful therapy in diseases as diverse as cancer, infertility, and diabetes.

Animals↗
PubMed2004

How to select stimuli for environmental sound research and where to find them.

A major methodological challenge in environmental sound research is to select appropriate stimuli. When an experiment involves a large number of sound sources, making custom recordings orproducing sounds live is frequently impractical or, for certain sounds, impossible. Existing databases of environmental sound recordings provide a researcher with a useful alternative. However, finding and selecting suitable sounds in such databases can be difficult because of the great variety of sounds present, poor documentation, questionable recording quality, and required purchasing costs. This article describes a number of practical issues to consider during the stimulus selection process, offers a preliminary compilation of existing resources for obtaining environmental sound recordings, provides some normative perceptual data that can be used as a reference for selecting stimuli and evaluating performance, and lists required characteristics and structural aspects of a research-oriented environmental sound database.

Adolescent↗
PubMedDate not supplied

[Simple obesity in children. A study on the role of nutritional factors].

UNLABELLED: Excessive amount of adipose tissue in children and adolescents and simple obesity in particular constitute a growing health problem throughout the world. Adverse health effects of obesity of children justify the need to look for efficient treatments, among them the dietary treatment. THE AIM OF THE STUDY was to examine the effectiveness of dietary treatment in children with simple obesity on the basis of thorough analysis of their state of nutrition, method of nutrition and eating habits and the impact of other environmental factors. Four research hypotheses were formulated: 1. simple obesity of children is influenced by selected environmental factors such as parents' level of education, familial inclination to obesity and health habits, 2. chosen and accepted by the child and/or its mother/parents programme of dietary treatment in the form of low-energy diet with elements of low glycemic index results in the loss of body mass in children, 3. implemented dietary treatment translates into the modification of basic anthropometric features--body mass, body height, thickness of skin and adipose folds on arm, below shoulder blade (scapula), on abdomen as well as arm circumference and anthropometric parameters of examined children--body mass index BMI, waste-hip ratio, body fat content, 4. implemented dietary treatment has an impact on modification of certain biochemical indicators--lipid profile of children with increased indicators of lipid metabolism. MATERIAL AND METHODS: The research concerned 236 children living in the Mazowsze region with diagnosed simple obesity (relative body mass index rel BMI =20%), directed to Gastroenterological and Endocrinological Unit of the Institute of Mother and Child, after the children and/or their mothers/parents had accepted participating in a ten-week long research programme. The state of nutrition was evaluated on the basis of the examination of 8 basic features and 5 anthropometric parameters and basic biochemical indicators of metabolism of carbohydrates and fats, before and after the beginning of dietary treatment. The assessments of the method of nutrition, including eating habits, proportions of food products in the food ration and nutritional value of daily food rations was conducted on the basis of 10-14-day records of the child's diet before the implementation of dietary treatment and on the basis of randomly selected 3-day records of the child's diet from the diet book after the dietary treatment was introduced. The environmental data were collected on the basis of a questionnaire, constructed for this study. RESULTS: The main risk factors for simple obesity in examined children (n=236) aged 3-15 yrs were familial and environmental conditions. A significant correlation was found between the children's obesity expressed by a normalized body mass index BMI z-score, unrelated to age and sex, and mother's level of education and father's obesity (Chi(2) test, p<0.05). A positive correlation was demonstrated between the normalized relative body mass index (BMI z-score) and children's anthropometrical parameters--thickness of skin and adipose folds on the arm, below the shoulder blade (scapula), on the abdomen and their sum, arm circumference, waste-hip ratio and body fat content and the children's parents body mass index (father's BMI, mother's BMI). In boys with simple obesity the tendency to central obesity was observed since early childhood. In the examined group of children no distortions of metabolism of carbohydrates were observed (correct fasting levels of glucose), while in children with obesity the irregularities of metabolism of fats were noted. The implemented dietary treatment (low energy diet with elements of low glycemic index) had a significant impact on improvement of lipid metabolism in all children in whom the irregularities of metabolism of fats were noted. Modification of the diet of children aged 3-6 by implementing dietary recommendations, including the increased frequency of meals and the choice of products with low glycemic index, did not have a significant impact on the decrease of the body mass index in 95% of examined children. A considerable number of children aged 3-6 (n=12) continued to eat only three meals a day and their model of nutrition, including the selection of products, was not significantly modified. The introduced low energy diet with elements of low glycemic index in children of school age (7-15 years) with simple obesity positively influenced the decrease of analyzed features and parameters (p<0.0001). During dietary treatment statistically significant decrease of the children's body mass was observed as well as a decrease of the thickness of skin and adipose folds on the arm, below the shoulder blade (scapula), on the abdomen and a decrease of arm circumference and body fat content. The change of the energy content of a daily food ration, the amount of consumed carbohydrates and products from the group of sugar and sweets, cereal foodstuffs and fat and products from the group of other fats was positively correlated with body mass loss expressed as the difference between z-score BMI before and after the dietary treatment. The modification of the eating habits--increased frequency of meals and reduction or elimination of eating between the meals during the nutrition intervention were not significantly linked to the change of normalized body mass index in the examined children. Only the frequency of eating sweets was related to the change of z-score BMI (p<0.05). The implemented dietary treatment in obese children aged 7-15 yrs significantly influenced the body mass loss. In children (n=38/236) with lipid metabolism abnormalities, the low energy diet with elements of low glycemic index had a favorable impact on the lipid profile. The increased levels of total cholesterol, LDL cholesterol and triglycerides returned to normal. CONCLUSIONS: 1. Simple obesity in children aged 3-15 yrs is connected with familial and environmental factors, including incorrect eating habits. 2. Dietary treatment consisting in the lowering of energetic value of the diet through the reduction of fat consumption and quantity and quality changes with respect to carbohydrates consumption decreased the children's obesity, and was more effective in the older age group (7-15 yrs). Dietary treatment normalizes the lipid profile in children. 3. Significant body mass loss has been observed in children in whose diet the amount of proteins and their share in the total energy value only slightly differs from the level before the dietary treatment. The amount of proteins in the children's diet was within the range of physiological recommendations.

Adolescent↗
PubMed1994

Comparison of CYP1A1 induction and genotoxicity in vitro as indicators of potentially harmful effects of environmental samples.

Cytochrome P450IA1 (CYP1A1) induction of Hepa-1 mouse and H4IIE rat hepatoma cell lines was compared using selected environmental samples. The results were in agreement for both cell lines: no induction was observed for the fly ash extract from peat combustion, an intermediate induction was found for the fly ash extract from biosludge combustion, and a strong induction was detected for natural peat extract. However, Hepa-1 responded to the samples more sensitively than did H4IIE: the half maximal induction (ED50) values for Hepa-1 were smaller than those for H4IIE. In a bacterial DNA repair assay without metabolic activation and in a mammalian sister chromatid exchange test in the presence of metabolic activation the samples were virtually non-genotoxic. Thus the CYP1A1-inducing potency and genotoxicity of the samples were not correlated. In light of these results, the CYP1A1 induction test might be a useful addition to conventional genotoxicity tests, which may fail to detect potentially harmful compounds/mixtures.

Animals↗
PubMed1988

Modeling hospital closure relative to organizational theory: the applicability of ecology theory's environmental determinism and adaptation perspectives.

The writers present a set of hypotheses testing the strength of organizational ecology theory's environmental determinism perspective and the adaptation perspective. Some of these hypotheses are analyzed relative to data on hospital closures in the United States between 1980 and 1985. Initial empirical analyses indicate that environmental determinism's liability of smallness holds relative to hospital closure, but the liability of newness doesn't hold. There are no published accounts where the liability of newness hypothesis hasn't held in research on other industries. The writers speculate that the inverse relationship between a highly changing health care environment and the liability of newness of hospitals may be because newer hospitals are better able to tap into the ongoing changes of the today's turbulent health care delivery environment in the United States. Also, analysis findings show that the environmental interdependence orientation of the adaptation models has some explanatory power in that hospitals with greater community support have much lower closure rates. Consideration of the more organization action oriented framework of the adaptation perspective is called for over the environmental determinism perspective that has been promoted in recent publications. The writers suggest that the more community sponsored a hospital is, the less likely its survival will hinge solely on standard environmental selection criteria, and that the ability of a hospital's administration to correctly adapt to environmental fluctuations is critical, especially in today's turbulent health care delivery environment in the United States.

Health Facilities↗
PubMed2005

A genetically informed study of marital instability and its association with offspring psychopathology.

Parental divorce is associated with a number of emotional and behavioral problems in young-adult offspring, but theoretical and empirical considerations suggest that the relation may be partially or fully accounted for by passive gene-environment correlation or environmental selection characteristics. The current study used the Children of Twins Design to explore whether shared environmental or genetic factors confound the relationship between parental marital instability and measures of psychopathology. Comparisons of the offspring of adult twins in Australia on 3 factors of abnormal behavior, including drug and alcohol, behavioral, and internalizing problems, suggest that environmental influences associated with divorce account for the higher rates of psychopathology. The results are consistent with a causal connection between marital instability and psychopathology in young-adult offspring.

Adult↗
PubMed1999

Distribution of exposure concentrations and doses for constituents of environmental tobacco smoke.

The ultimate goal of the research reported in this series of three articles is to derive distributions of doses of selected environmental tobacco smoke (ETS)-related chemicals for nonsmoking workers. This analysis uses data from the 16-City Study collected with personal monitors over the course of one workday in workplaces where smoking occurred. In this article, we describe distributions of ETS chemical concentrations and the characteristics of those distributions (e.g., whether the distribution was log normal for a given constituent) for the workplace exposure. Next, we present population parameters relevant for estimating dose distributions and the methods used for estimating those dose distributions. Finally, we derive distributions of doses of selected ETS-related constituents obtained in the workplace for people in smoking work environments. Estimating dose distributions provided information beyond the usual point estimate of dose and showed that the preponderance of individuals exposed to ETS in the workplace were exposed at the low end of the dose distribution curve. The results of this analysis include estimations of hourly maxima and time-weighted average (TWA) doses of nicotine from workplace exposures to ETS (extrapolated from 1 day to 1 week) and doses derived from modeled lung burdens of ultraviolet-absorbing particulate matter (UVPM) and solanesol resulting from workplace exposures to ETS (extrapolated from 1 day to 1 year).

Absorption↗
PubMed1989

Nosocomial aspergillosis: environmental microbiology, hospital epidemiology, diagnosis and treatment.

The purpose of this review is to characterize the environmental microbiology, hospital epidemiology, diagnosis and treatment of nosocomial aspergillosis. Appropriate environmental control measures are important in preventing or arresting an outbreak of nosocomial aspergillosis. These include selective environmental microbiological surveillance and floor to ceiling barriers during construction or renovation. These is particularly important for the bone marrow transplant units and units with persistently granulocytopenic patients. We have summarized the point source and cited or formulated the environmental correction measures relating to 25 outbreaks of nosocomial aspergillosis involving a total of more than 100 patients. The most frequent settings of nosocomial invasive aspergillosis occurred in granulocytopenic patients following respiratory infection from an airborne source, associated with hospital construction or contaminated ventilation systems.

Aspergillosis↗
PubMed1995

Learning and evolution: a quantitative genetics approach.

Recent models of the interactions between learning and evolution show that learning increases the rate at which populations find optima in fixed environments. However, learning ability is only advantageous in variable environments. In this study, quantitative genetics models are used to investigate the effects of individual learning on evolution. Two models of populations of learning individuals are constructed and analyzed. In the first model, the effect of learning is represented as an increase in the variance of selection. Dynamical equations and equilibrium conditions are derived for a population of learning individuals under fixed and variable environmental selection. In the second model, the amount of individual learning effort is regulated by a second gene specifying the duration of a critical learning period. The second model includes a model of the learning process to determine the individual fitness costs and benefits accrued during the learning period. Individuals are then selected for the optimal learning investment. The similarities of the results from these two models suggest that the net effects of learning on evolution are relatively independent of the mechanisms underlying the learning process.

Animals↗
PubMed1993

Environmental epidemiologic issues and minority health.

There exist great differences in morbidity and mortality across racial, cultural, and socioeconomic groups. Certain factors, like limited access to health care, are known to contribute to these differences. The contribution of other factors, like disparities in exposure to environmental hazards, is largely unknown as to the effect on minority groups' morbidity and mortality. This article describes select environmental hazards faced by minorities, such as lead toxicity in children, proximity to hazardous waste sites, and consumption of food contaminated with toxic substances, as well as the role of epidemiologists in documenting adverse health effects and participation in interventions to prevent them.

Child, Preschool↗
PubMed2005

Environmental reduplicative paramnesia in a case of atypical Alzheimer's disease.

A 79-year-old patient with neuropathologically confirmed Alzheimer's disease (AD) presented with a selective environmental reduplicative paramnesia (RP), the belief that one or more environments exist simultaneously in two or more physical locations. Clinical presentation and neuropathological examination revealed an atypical form of AD. High neurofibrillary tangle densities were observed in the frontal and temporal association cortex, whereas the parietal and entorhinal cortex, as well as the hippocampus, were nearly spared. These findings are compared to those reported in frontal and frontotemporal variants of AD and discussed in the light of current anatomoclinical models for environmental RP.

Activities of Daily Living↗
PubMed1996

Environmental determinants of selected family-oriented health indicators.

Based on the levels of environmental contamination and degradation, synthetic measures of environmental hazards in urban and rural regions in Poland were developed. At the same time, negative family health indicators associated with environmental contamination were determined. These indicators included: low birth weight, fraction of deaths with low birth weight, excessive male and female mortality in the 30-64 age group. The study revealed a relationship between synthetic measures of environmental hazards and selected health indicators. This relationship, along with the spatial distribution of areas with the highest index values, should be taken into consideration while planning improvements and preventive activities.

Environmental Pollution↗
PubMed2003

Environmental and behavioral factors are associated with the calcium intake of low-income adolescent girls.

Based on social cognitive theory, the purpose of this study was to determine whether selected environmental and behavioral factors were associated with the calcium intake of low-income adolescent girls. Teachers in three public middle schools administered a written survey resulting in data from 105 girls (the majority were Asian American). Calcium intake was lower than recommended and was associated with eating breakfast, number of children in the household, availability of some high-calcium foods, and seeing important others drink milk or being encouraged to drink milk. Educational interventions should be targeted to parents in relation to making affordable sources of calcium available and modeling adequate intake to adolescents.

Adolescent↗
PubMed2000

The nature of the organism. Life has a life of its own.

The question of closure in biological systems is central to understanding the origins of the biological variation and complexity upon which various forms of selection act. Much of evolutionary theory, especially in the second half of the twentieth century, is concerned with the consequences of environmental selection acting on bio-diversity, but neglects questions of the origin of that diversity. This has permitted us to act as if an explanation of consequences was the ultimate explanation in biology. However, Darwin understood that evolution was both information driven and information constrained. The link between evolutionary constraints and closure can be profitably explored by starting with Darwin's notion of the primary of "the nature of the organism" over "the nature of the conditions" articulated in the sixth edition of Origin of Species. Contemporary ideas of self-organization, emergence, complexity, and inherent (developmental and phylogenetic) constraints can be seen as an elaboration and refinement of Darwin's views if we adopt the following perspective: (1) information is cheap, not costly, to produce, but may have costly consequences; and (2) information is produced by systems that are informationally closed but remain thermodynamically open.

Biological Evolution↗
PubMed2003

A review of environmental toxicant analysis by using multidimensional gas chromatography and comprehensive GC.

The purpose of this review is to highlight the developments in coupled-column gas chromatography methods for qualitative analysis of selected environmental toxicants such as dioxin, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), etc. In particular, the new technique of GC x GC will be introduced, and its role, and the promise it offers to this field is discussed. The benefits of enhanced separation to quantitative analysis will be considered. In order to perform an accurate risk assessment, both the dose and biological effects of environmental toxicants have to be determined with a high degree of certainty. This is most often achieved by using chromatographic methods. Given the complexity of most environmental sample extracts, single-column gas chromatography is unable to fully resolve all the components of interest frequently leading to a positive bias in the reported concentrations. Advanced separation tools, such as multidimensional gas chromatography (MDGC), were investigated quite early and demonstrated improvements in separation. However, limitations in the number of target analytes that could be analyzed in a single run as well as insufficient robustness lead to a continued interest in alternative solutions. The parallel development of mass spectrometric identification and quantification strategies proved useful in many cases, although it frequently failed to provide positive identification of chromatographically unresolved isomeric compounds. More recently, comprehensive two-dimensional gas chromatography (GC x GC) may offer a solution to that problem, especially because it offers enhanced resolution for complex mixtures containing trace level environmental toxicants.

Chromatography, Gas↗