Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Environment”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,225 records · Page 68Linked to original sources
PubMed1981

Alcohol ingestion and man's ability to adapt to exercise in a cold environment.

Previous work from this laboratory indicated that when alcohol was ingested prior to performing two hours of mild exercise in a cold environment, subjects experienced greater heat loss and lower blood glucose levels. The present study expanded the protocol to three hours in order to establish if these detrimental effects continued when blood alcohol levels declined. Young, male volunteers (n = 6) ingested water, water and alcohol (2.5 ml/Kg) or water, alcohol (2.5 ml/Kg) and dextrose (50 gm/150 ml water) on different occasions. The 3 treatments were administered by a balanced design. Following fluid ingestion, the subject performed intermittent, bicycle work (40% VO2max) with a 20 min work--10 min rest pattern for 3 hr. in a -5 degrees C environment. VO2, R, and blood glucose data did not reveal any significant metabolic effects of alcohol. The water-alcohol ingestion resulted in a peak blood level (13.05 +/- 2.34 mM l-1) after 69 +/- 39 min. During the third hour there was a decline to 60% of the peak value. With dextrose, the peak level was less (9.29 +/- 2.62 mM . l-1) (p less than or equal to 0.05) and occurred almost one hour later (p less than or equal to 0.05). Generally the alcohol-dextrose data were similar to the previous study in that the alcohol treatment resulted in a significantly greater heat loss (p less than or equal to 0.05). During the third hour the skin and core temperatures remained constant in the control and alcohol-dextrose treatments; however, in the alcohol series the values rose and approached control levels. The study confirmed that moderate levels of blood alcohol can impair thermoregulation while performing mild exercise in a cold environment and thus alcohol ingestion prior to any activity in a cold environment is contraindicated. However, the impairment dissipates when the blood alcohol is metabolized. When alcohol is ingested with dextrose, the alcohol effects are reduced.

Adaptation, Physiological↗
PubMed1982

Student perception of school environment and its relationship to mood, achievement, popularity, and adjustment.

This study examined relationships between student perceptions of classroom environment and mood, achievement, popularity, and adjustment, both for students in general and for "problem" (i.e., acting-out, anxious, and unpopular) children. Subjects included 511 fifth- and sixth-grade students from 23 classes in four suburban schools. Class environment was assessed by responses to a short form of the Classroom Environment Scale (CES). Students also completed mood adjective checklists and peer sociometric ratings. Reading and arithmetic report card grades and achievement test scores were recorded for the school year, and teachers submitted adjustment ratings for all students. Classes, rather than students, were used as the main unit of analysis. For classes in general, high perceived Order and Organization and Affiliation related to greater student popularity. Relationships between perceptions of class environment and the dependent measures were stronger for problem students. For that group, high perceived Order and Organization, Affiliation, and Innovation related to positive mood, greater peer popularity, and teacher ratings indicating more positive adjustment.

Achievement↗
PubMed1981

Failure to preserve cortical binocularity in strabismic monkeys raised in a unidirectional visual environment.

It has been claimed that cortical binocularity can be preserved by raising exotropic kittens in a visual environment consisting of spatially periodic contours. We raised visually immature monkeys (Macaca mulatta) with prismatically or surgically induced horizontal and vertical strabismus in a visual environment consisting exclusively of vertical stripes. Electrophysiologic studies of the striate cortex yielded results that are comparable to those obtained in strabismic monkeys raised in an unrestricted visual environment. Thus we cannot confirm in strabismic monkeys that binocularly responding cortical neurons can be preserved by exposing the animals to a nonconflicting repetitive visual environment

Animals↗
PubMed1981

Relationship between home environment and school adjustment of TMR children.

The relationship between the home environment and school adjustment of 104 TMR children was examined. Assessment of home environment included measurement of environmental process variables with Caldwell's HOME Inventory and psychosocial climate with Moos, Insel, and Humphrey's Family Environment Scale. Certain child-rearing attitudes and relevant demographic characteristics were also investigated. Measures of school adjustment included the child's social status, self-concept, and IQ and teacher's ratings of classroom behavior. Results revealed that specific factors of home environment were significantly related to the adjustment of TMR children in school including (a) harmony and quality of parenting, (b) educational and cognitive stimulation available at home, (c) emotional support for learning, and (d) cohesiveness of family members.

Adaptation, Psychological↗
PubMed1980

Contributions of the caregiving environment to increased lead burden of children.

Two groups of children, 12 to 30 months (n = 14) and 31 to 78 months of age (n = 12), showing increased lead burden were compared to a sample of children matched for age, sex, and socioeconomic status but showing no evidence of increased lead burden. All children were screened at a local county health department because of suspected lead exposure or as part of the Early and Periodic Screening, Diagnosis, and Treatment Program. The quality of the caregiving environment was assessed using the HOME Inventory. A measure of maternal intelligence was also obtained. For the younger children, significant deficits in maternal IQ and quality of the caregiving environment were associated with increased lead burden. In particular, the subscales of the HOME Inventory dealing with emotional and verbal responsivity of the mother and maternal involvement with the child were significantly lower for children with increased lead burden. For the older children there was no significant association between lead burden and home environment or maternal IQ. The results suggest that intellectual deficits previously attributed to lead toxicity may be related to compromised home environment.

Child↗
PubMed1980

Type A coronary-prone behavior in the work environment.

The model presented in this paper accounts for the relationship between Type A behavior and the work environment and identifies: (1) susceptible Type A individuals; (2) potential occupational stressors in the work environment; (3) subsequent resulting control conflict and maladaptive coping behavior; (4) feedback error and time lag resulting in detrimental symptoms; and (5) methods of changing Type A behavior (Fig 1). From this literature review, it becomes clear that there is a need for further prospective research especially in the area aimed at isolating and determining the specific work environment variables which enhance Type A behavior. As yet, no prospective research project is known which has followed a sample of employees from their job application and interview situation through their careers, in order to investigate changes in, and influences on, Type A behavior patterns. Finally, there is an obvious need for the introduction of more Type A behavior modification programs for workers, and perhaps more emphasis should also be directed toward changing the Type A behavior pattern socialization process, which appears to be so prevalent in urban, middle-class home environments.

Age Factors↗
PubMedDate not supplied

Reducing crying and irritability in neonates using a continuously controlled early environment.

A mother's "holding" environment has been shown to be effective in reducing infant crying and irritability. When mothers hold or cuddle their infants they create a microenvironment with stimuli similar to those of the intrauterine environment. Several of these same stimuli were incorporated into a cradle designed to provide a similar "holding" environment for the infant when the mother was not there. Ninety healthy term newborn infants were randomized to an experimental (n = 45) or control group (n = 45). The experimental group used a cradle that produced motion, sound, tactile (containment), and reduced-light stimuli at stimulus levels that initially approximated intrauterine sensory stimulation levels and gradually decreased to the levels of the home environment over 16 weeks. The control group used an identical cradle with no stimulus modulation features. Infants were placed in their respective cradles from 2 hours after birth during the times they would normally be placed in an infant bed. The mother-infant interaction or parenting style was not changed or manipulated. Mothers' use of the cradles did not differ significantly. An electronic status monitor measured and recorded infant presence and crying in the cradles. The Brazelton Neonatal Behavioral Assessment Scale test was done at 1 to 2, 14, and 24 days of age by "blinded" examiners. Additionally, phone calls and home visits were conducted by a registered nurse.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1977

Nutrition and the responses to extreme environments.

The calorie requirements of adequately clothed men living and working in a cold environment are not increased, except for the 2-5 percent increase in matabolic rate due to the "hobbling" effect of the heavy clothing. The energy requirements in the cold, as in a temperate environment, are primarily a function of body weight and level of physical activity. The discrepancies between studies of persons living in a hot environment are explainable and are primarily due to the level of protection from the heat. The increased requirements are probably due to the increased heat load imposed on the body by solar radiation and the extreme heat. The increased requirements, in all likelihood, are a combination of increased action by blood in heat transport, increased ventilation and heart rate, and increased action of the sweat glands plus the increase in metabolic rate due partially to elevation in body temperature. In view of some strong new evidence, the energy requirements are increased for individuals living and working in extremely hot environments. There is no evidence showing that modification of macro nutrient composition of the diet will enhance either heat tolerance or cold adaptation in humans. Recent studies indicate that high carbohydrate diets will improve tolerance during high altitude exposure.

Animals↗
PubMed1996

[The microclimate conditions of the environment for treating patients in hospital clinics and wards (a review)].

The problem of the microclimatic parameters of the environment in some clinics and hospital departments is discussed as well as their significance in the general therapeutic course. The impact of the air environment as a potent therapeutic factor is outlined. It is stated that the temperature regime in the rooms must be differentiated in accordance to the climatic conditions, seasons, patient's age, the nosologic group. Discussing the problem with regard to the balance "man-environment" it is outlined that the adaptive capabilities, which are narrowed and altered in the patient, can not compensate for the unfavourable conditions of the environment. The authors point at differentiated values of the microclimatic parameters for the rooms in some clinics and departments.

Health Facility Environment↗
PubMed1996

[A national plan for action on the environment and health].

Preserving the environment and human health is an irreversible part of the activity towards stable development. Acknowledging the necessity of such development, the European countries commence working out of plans that subordinate their policy to this object. Concerning the health policy the new strategy requires improving of the integrated system for environmental and health control-an administrative framework that reflects the partnership between health and environmental institutions and the other sectors at all levels of control. The main means and instruments for control of health and the environment are: 1) information system for health and environment; 2) identification and evaluation of the health and environmental risks; 3) a framework of the current legislation; 4) additional measures for control, including economical and fiscal instruments; 5) professional training and qualification; 6) public information and health education; 7) public participation; 8) researches and technological works. The correct functioning of the complex "taking decisions-control system" and the expected results depend on the adequate working out and application of the above mentioned means. The national action plan for environment and health is a fundamental project on a large scale for preserving the health and environmental interests of the country targeting at its stable progress.

Bulgaria↗
PubMed1998

Polygenic mutation in Drosophila melanogaster: genotype x environment interaction for spontaneous mutations affecting bristle number.

A highly inbred line of Drosophila melanogaster was subdivided into replicate sublines that were subsequently maintained independently with 10 pairs of parents per generation. The parents were randomly sampled for 19 'unselected' sublines and artificially selected for high or low abdominal or sternopleural bristle number for 12 'selected' sublines (with 3 replicate selection lines/trait/direction of selection). Divergence in mean bristle number among the unselected sublines, and response of the selected sublines to selection, are attributable to the accumulation of new mutations affecting bristle number. The input of mutational variance per generation, VM, can be estimated from the magnitude of response or divergence, assuming neutrality of mutations affecting the bristle traits. We reared unselected lines at generations 222 and 224, and selected lines at generations 182-184 of mutation accumulation at each of three temperatures (18 degrees C, 25 degrees C, 28 degrees C), and estimated the mutational variance common to all environments and the mutational variance from genotype x environment interaction. For sternopleural bristle number, the mutational interaction variance was 26% of the mutational variance common to all temperatures, and the interaction variance was due to temperature x line interaction. For abdominal bristle number, the mutational interaction variance was 142% of the mutational variance common to all temperatures, and the interaction variance was due to interactions of temperature x line, sex x line, and temperature x sex x line. It is possible that segregating variation for bristle number is maintained partly by genotype x environment interaction, but information on the fitness profiles of mutations affecting bristle number in each environment will be necessary to evaluate this hypothesis quantitatively.

Abdomen↗
PubMed1998

[Factors aggravating bronchial asthma in urban children (II)--The involvement of atopy and serum fatty acids, and their interaction with urban living environment].

The aggravation of bronchial asthma in today's urban child population was studied by an epidemiological study in order to elucidate the involvement of food habits as well as individual factors such as age, sex, and history of atopic dermatitis, and the interaction with urban living environments. The asthma group consisted of 202 children under 12 years old who had been recently diagnosed as having bronchial asthma and under the care of Osaka Prefectural Habikino Hospital. The non-asthma group consisted of 81 children under 12 years old who had been under care at Osaka Prefectural Hospital but had no present history of allergic symptom. The individual factors and the urban living environments (atmospheric environment, housing style) were surveyed by questionnaire. Also, the mite (Dp: Dermatophagoides pteronyssinus, Df: Dermatophagoides farinae) specific immunoglobulin E (Dp-IgE, Df-IgE) and the composition of serum fatty acid were examined as objective indicators for atopy and dietary habits, respectively. In this study, bronchial asthma was classified into two types: atopic/non-atopic, according to whether Dp-IgE was present/absent (positive/negative). Thus, for the risk factors given above, their involvement in each type of asthma was examined. As atopy is an important factor of child asthma, the relative risk (odds ratio) of Dp-IgE increase (atopy) was also examined by logistic regression analysis in each of the asthma and non-asthma groups. The results are as follows: 1. As age increased, the risk of atopy increased but the risk of asthma decreased. 2. The risk of asthma increased as Dp-IgE rather than Df-IgE increased. 3. For the composition of serum fatty acid, the lower quartile ranking (LQR) group for a saturated fatty acid, stearic acid, and the upper quartile ranking (UQR) group for a mono-unsaturated fatty acid, oleic acid, had a higher risk of nonatopic asthma. 4. The LQR group for omega 6-poly-unsaturated fatty acid such as linoleic acid, had a lower risk of atopy. 5. The UQR group for a omega 3-poly-unsaturated fatty acid, eicosapentaenoic acid, had a higher risk of nonatopic asthma. The UQR of eicosapentaenoic acid and living environments within 25 m from a major road or housing of reinforced concrete structure showed involvement in synergistic increase in the risk of non-atopic asthma.

Asthma↗
PubMed1998

Demography and the environment.

Demographers' interest in the environment has generally been enmeshed in broader issues of population growth and economic development. Empirical research by demographers on environmental issues other than natural-resource constraints is limited. In this paper, I briefly review past demographic thinking about population and the environment and suggest reasons for the limited scope of demographic research in this area. Next, I describe more recent demographic research on the environment and suggest several newer areas for demographic research. Finally, I consider the future of research on the environment in the field of demography.

Demography↗
PubMed2000

The relative order of helical propensity of amino acids changes with solvent environment.

A model peptide of sequence Ac-Y-VAXAK-VAXAK-VAXAK-NH(2), where X is substituted with one of nineteen amino acids (P excluded), was synthesized and titrated with methanol to study helical propensity as a function of solvent environment. The CD spectra of these peptides are largely random coil in 2 mM sodium phosphate buffer (pH 5.5) and show a conformational change to alpha-helix with increasing methanol content. Singular value decomposition was used to correct the CD spectra for the absorbing side chains of W, Y, F, C, and M, and this correction can be substantial. With correction both W and F become good helix formers. The free energy for helix propagation was calculated using the Lifson-Roig statistical model for each of the nineteen amino acids at each point in their titration. The results show that the rank order of helical propensity for the nineteen amino acids changes with solvent environment. This result will be particularly important if proteins undergo hydrophobic collapse before secondary structures are formed, because amino acids can then see different solvent environments as the secondary structures are formed. Related amino acids are found to have interesting correlations in the shape of their titration curves. This finding provides one explanation for the limiting 70% accuracy in predicting secondary structure from sequence, since the helical propensities used are calculated for an average solvent environment. Proteins 2000;39:132-141.

Amino Acid Sequence↗
PubMed2000

A data fusion environment for multimodal and multi-informational neuronavigation.

OBJECTIVE: Part of the planning and performance of neurosurgery consists of determining target areas, areas to be avoided, landmark areas, and trajectories, all of which are components of the surgical script. Nowadays, neurosurgeons have access to multimodal medical imaging to support the definition of the surgical script. The purpose of this paper is to present a software environment developed by the authors that allows full multimodal and multi-informational planning as well as neuronavigation for epilepsy and tumor surgery. MATERIALS AND METHODS: We have developed a data fusion environment dedicated to neuronavigation around the Surgical Microscope Neuronavigator system (Carl Zeiss, Oberkochen, Germany). This environment includes registration, segmentation, 3D visualization, and interaction-applied tools. It provides the neuronavigation system with the multimodal information involved in the definition of the surgical script: lesional areas, sulci, ventricles segmented from magnetic resonance imaging (MRI), vessels segmented from magnetic resonance angiography (MRA), functional areas from magneto-encephalography (MEG), and functional magnetic resonance imaging (fMRI) for somatosensory, motor, or language activation. These data are considered to be relevant for the performance of the surgical procedure. The definition of each entity results from the same procedure: registration to the anatomical MRI data set (defined as the reference data set), segmentation, fused 3D display, selection of the relevant entities for the surgical step, encoding in 3D surface-based representation, and storage of the 3D surfaces in a file recognized by the neuronavigation software (STP 3.4, Leibinger; Freiburg, Germany). RESULTS: Multimodal neuronavigation is illustrated with two clinical cases for which multimodal information was introduced into the neuronavigation system. Lesional areas were used to define and follow the surgical path, sulci and vessels helped identify the anatomical environment of the surgical field, and, finally, MEG and fMRI functional information helped determine the position of functional high-risk areas. CONCLUSION: In this short evaluation, the ability to access preoperative multi-functional and anatomical data within the neuronavigation system was a valuable support for the surgical procedure.

Adult↗
PubMed1999

Case-parents design for gene-environment interaction.

The scientific and public health implications of gene-environment interaction warrant that the most powerful study designs and methods of analysis be used. Because traditional case-control designs, which use nonrelated subjects, have demonstrated the need for large samples to detect interactions, alternative study designs may be worthwhile, such as sampling diseased cases and their parents. If the transmission of particular alleles from parents to their diseased child appears to be distorted from Mendelian expectation, then this suggests an etiologic association of the alleles with disease; if the frequency of transmission differs between exposed and nonexposed cases, then gene-environment interaction is suggested. We present likelihood-based methods to assess interaction, as well as an extension of the transmission/disequilibrium test (TDT). For these statistical tests, we also derive methods to compute sample size and power. Comparisons of sample size requirements between the case-parents design and the case-control design indicate that the case-parents design can be more powerful to detect gene-environment interactions, particularly when the disease susceptible allele is rare. Also, one of the derived likelihood methods, based on additive effects of alleles, tended to be the most robust in terms of power for a broad range of genetic mechanisms, and so may be useful for broad applications to assess gene-environment interactions.

Case-Control Studies↗
PubMed1999

Structure investigation of amphiphilic cyclopeptides in isotropic and anisotropic environments-A model study simulating peptide-membrane interactions.

It has been proposed that the membrane allows a much more efficient binding of certain small or medium-sized amphiphilic messenger molecules to their receptor, not only by accumulation of the drug, but also by induction of orientations and conformations that are much more favorable for receptor docking than structures adopted in isotropic phases. A series of eight amphiphilic cyclic peptides containing lipophilic (L-alpha-aminodecanoic acid = Ada, L-alpha-aminohexadecanoic acid = Ahd, Nhdg = N-hexadecylglycine) and hydrophilic (Lys, Asp) amino acids were synthesized and examined by means of NMR spectroscopy and molecular dynamics (MD) simulations in isotropic (CDCl3) and membrane-mimicking anisotropic (SDS/H2O) solvents to study the influence of the environment on their individual conformations. NMR data of cyclo(-Gly1-D-Asp2-Ahd3-Ahd4-Asp5-Gly6+ ++-) (C4), cyclo(-Lys1-D-Pro2-Lys3-Ada4-Pro5-Ada6-) (C5) and cyclo(-Lys1-Pro2-Lys3-Ada4-D-Pro5-Ada6-) (C6) clearly indicate that those compounds are too rigid to perform a conformational change upon transition from an isotropic to an anisotropic environment. On the other hand, the experimental data of cyclo (-Gly1-Asp2-Ahd3-Ahd4-Asp5-Gly6-) (C1), cyclo(-Asp1-Ala2-Nhdg3-Ala4-D-Asp5-) (C7), and cyclo(-D-Asp1-Ala2-Nhdg3-Ala4-Asp5-) (C8) suggest highly flexible unstructured molecules in both environments. However, for cyclo(-Asp1-Asp2-Gly3-Ahd4-Ahd5-Gly6-) (C2) we observed a structure inducing effect of a membrane-like environment. The compound populates three different conformations in SDS/H2O, whereas in CDCI3 no preferred conformation can be detected. cyclo(-D-Asp1-Asp2-Gly3-Ahd4-Ahd5-Gly6-) (C3) clearly exhibits two different conformations with a shifted beta,beta-turn motif in CDCI3 and SDS/H2O solutions. The conformational change could be reproduced in a restraint-free MD simulation using the biphasic membrane mimetic CCl4/H2O. Our results give clear evidence that membrane interactions may not only lead to structure inductions, but can also induce major conformational changes in compounds already exhibiting a defined structure in isotropic solution.

Carbon Tetrachloride↗
PubMed2002

Developmental behavior of gene expression for brown rice thickness under different environments.

The dynamic changes of genetic effects, including main effects, and genotype x environment (GE) interaction effects on brown rice thickness (BRT) across environments were investigated by using the developmental genetic models. Seven cytoplasmic male sterile lines of indica rice (Oryza sativa L.) as females and five restoring lines as males were used in a factorial design to produce grains of F(1)s and F(2)s in two environments (years) for developmental genetic analysis. The results indicate that genetic effects, especially GE interaction effects of triploid endosperm genes, cytoplasm genes, and diploid maternal plant genes were important to the performance of BRT at various filling stages of rice. The BRT was genetically controlled by the net genetic effects of genes expressed at the early and late filling stages (1-7 days and 15-21 days after flowering, respectively). The differences in net genetic effects under different environments for endosperm, cytoplasm, and maternal plant genes were found, and the net GE interaction effects were more important to BRT at the early filling and mature stages of rice. Some net genetic effects, especially for net cytoplasm effects spasmodically expressed, were detected among filling stages. Higher additive and cytoplasm main effects, along with their interaction effects, were found, which would be useful for selection for BRT in breeding programs. The predicated genetic effects at different filling stages show that the parents of V20 and Xieqingzao were better than others for improving BRT of progenies.

Analysis of Variance↗