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PubMed1991

[Environment, chemicals and public health].

It is obvious that, to the general public, environmental pollution determines the state of public health to a considerable extent. Scientifically, however, this relationship is less readily detectable, particularly when the environment polluted by chemicals is the polluted human environment. It is more correct to define 'environment' to include both the 'external' and the 'local' environment. The external environment includes a part which is directly affected by man, for instance when man-made chemicals are involved as well as the natural environment. The local or personal environment particularly concerns matters which may be comprised in the term 'lifestyle'. The above forms of environment may all affect health, although effects may differ in quality and quantity. These relationships are discussed, with special reference to the occurrence of cancer.

Carcinogens↗
PubMed1986

Acid-base balance and blood lactate and pyruvate levels in albino rats bred under normobaric hypoxia or normoxia, after muscular work in a hypoxic or hypoxic-hypercapnic environment.

Albino rats, Wistar family, have been raised since birth in normobaric hypoxic environment (10-12% O2). This hypoxic animal group and a normoxic animal group were subjected to muscular fatigue by forced march within revolving room. Normoxic animals were subjected to 3 spaced trials: in normoxic environment; in hypoxic normobaric environment; in the same hypoxic normobaric environment with about 2% CO2 added. Hypoxic animals were subjected to 2 spaced trials: in hypoxic normobaric environment; in the same hypoxic environment with about 2% CO2 added. At the end of every single trial, lactatemia, blood pyruvate, acid-base balance and the erythrocytic number were examined. Albino rats raised in hypoxic environment since birth, subjected to muscular work in hypoxic environment showed a smaller increase of lactatemia and a moderate variation of the acid-base balance, compared to normoxic animals in the same conditions. CO2 added to the respired hypoxic mixture during muscular work, attenuated in both animal groups, the observed modifications. Finally we found that the erythrocytes per mm3 of blood increased from the second drawing of blood.

Acid-Base Equilibrium↗
PubMedDate not supplied

Physiological responses during work in hot humid environments.

Studies have been conducted on 6 young healthy Indians in simulated comfortable, hot humid and very hot humid conditions to evaluate the physiological reactions during work. Physiological responses like exercise oxygen consumption (VO2), pulmonary ventilation (VE) and heart rate (HR) were noted during sub-maximal fixed work rates of 400, 500 and 600 kgM/min. In addition, duration of continuous work at these three rates of work, in the three simulated environments was also noted. Physiological responses i.e. VO2, VE and HR were noted every 15 minutes of work. Besides these responses, rectal temperature (Tr), mean skin temperature (Ts) and mean sweat rate were also noted during the continuous work. Results indicated a significantly higher oxygen cost (VO2) during 400 kgM/min of work in hot and very hot humid environments whereas, in the higher rates of work, the changes were not significant. The cardiac frequency showed a significantly higher rise during different grades of activities in hot and very hot environments except in the highest work rate in hotter environments, possibly due to attainment of maximum heart rate. The duration of continuous physical efforts in various grades of activities decreased significantly (P less than 0.001) in hot humid environments than in the comfortable temperature. During the progression of the work, the mean skin temperature decreased in comfortable temperature but increased in hot humid environments. The mean rectal temperature, increased during work in hot humid environment, and the rate of rise was much faster in higher work rates attaining the target temperature much earlier. The rate of sweating increased significantly as the heat load of the body increased. In hot humid environments, work performance decreased due to early attainment of maximum heart rate, reduction in VO2 max, disproportionate rise in rectal temperature, narrowing of the difference between the core and the skin temperature and attainment of maximum sweating rate.

Adult↗
PubMed2003

Context-dependent memory in a meaningful environment for medical education: in the classroom and at the bedside.

PURPOSE: Learning-in-context is a much-discussed topic in medical education. Information is said to be better recalled when the learning environment resembles the later retrieval environment. Godden and Baddeley (1975) showed that divers recalled words better when the recall condition matched the original learning environment, i.e. underwater or on land. Though it is unclear whether the findings can be generalized for medical education, medical educators regularly refer to them. We replicated the Godden and Baddeley study in ecologically more valid conditions for medical education and extended it with meaningful subject matter (namely, a patient case description). METHOD: Sixty-three clerks were randomized over four conditions, contrasting a clinical (bedside) with an educational (classroom) environment as both learning and recall conditions. Students were asked to recall a list of words and a patient case in the same environment or in the opposite environment as where they learned it. RESULTS: We failed to find a significant same-context advantage for free recall of the list of words and the patient case propositions. However, there does appear to be a slight tendency towards better recall of the case description when learning took place in the clinical environment. DISCUSSION: In medical education, the context, if conceived as physical surroundings, does not seem to contribute to a same-context advantage. One should be cautious in generalizing the findings of Godden and Baddeley. However, different forms of 'context' other than the physical one used in the Godden and Baddeley study may well enhance learning effects in medical education.

Analysis of Variance↗
PubMed1995

Environment influences functional outcome of cerebral infarction in rats.

BACKGROUND AND PURPOSE: The purpose of this study was to determine whether preoperative and postoperative enrichment of the environment can enhance the functional outcome after cerebral infarction in rats. METHODS: The right middle cerebral artery was ligated in adult spontaneously hypertensive male rats, and the functional outcome was studied for 12 weeks after the operation. Three groups were compared: A, rats kept in individual cages before and after the operation (n = 9); B, rats kept in individual cages before the operation but transferred to an enriched environment after the operation (n = 10); and C, rats kept in an enriched environment all the time (n = 12). The enriched environment consisted of a large cage with opportunities for various activities, but rats were not forced to do any particular tasks. RESULTS: Rats kept in an enriched environment (groups B and C) performed significantly better than rats in group A in a leg-placement test, beam walking, walking on a rotating pole, and climbing. The infarct size and thalamic atrophy did not differ among the groups. CONCLUSIONS: The laboratory environment is important for the functional outcome in brain ischemia. We hypothesize that an enriched environment may stimulate mechanisms that enhance brain plasticity after focal brain ischemia.

Animals↗
PubMed2004

Multisensory environments for leisure: promoting well-being in nursing home residents with dementia.

Multisensory environments such as Snoezelen rooms are becoming increasingly popular in health care facilities for older individuals. There is limited reliable evidence of the benefits of such innovations, and the effect they have on residents, caregivers, and visitors in these facilities. This two-stage project examined how effective two types of multisensory environments were in improving the well-being of older individuals with dementia. The two multisensory environments were a Snoezelen room and a landscaped garden. These environments were compared to the experience of the normal living environment. The observed response of 24 residents with dementia in a nursing home was measured during time spent in the Snoezelen room, in the garden, and in the living room. In the second part of the project, face-to-face interviews were conducted with six caregivers and six visitors to obtain their responses to the multisensory environments. These interviews identified the components of the environments most used and enjoyed by residents and the ways in which they could be improved to maximize well-being.

Affect↗
PubMedDate not supplied

[Work environment at a university hospital: perception of nurses].

Knowledge of the work climate is important in all organizations since the this climate can either contribute to or limit the development and sense of fulfillment of those working within the workplace. The aim of this study was to describe the nurses' perception of the working environment in a university hospital. Two-hundred and thirteen nurses completed a self-administered questionnaire which included the Work Environment Scale (WES) translated to Spanish. The nurses perceived that involvement and cohesion among colleagues was high. The support of the supervisor as well as the autonomy given to nurses in their work was considered moderate. The nurses also highlighted organizational aspects, i.e. planning and efficiency at work and the clarity of what was expected of them in their daily activities. The perception of the work environment differed among the various nursing units. In general, nurses with the fewest years of professional experience perceived the work environment more positively. This study has enabled the determination of a work environment profile of a group of nurses in a university hospital. Moreover, guidance is offered to nurse managers of the nursing units on the positive aspects of the work environment which should be reinforced and on the negative aspects which should be modified in order to create an optimal work environment.

Adult↗
PubMed1988

Effect of maternal presence on the fear response to an unfamiliar environment as measured by heart rate in rats as a function of age.

Rats 16 to 60 days of age were placed in an unfamiliar environment either alone or in the presence of an anesthetized lactating dam. Rats of all ages show a dramatic increase in fear, as measured by heart rate (HR), when placed alone in an unfamiliar environment. Adult rats, however, show a rapid decline in heart rate during the course of a 90-min session, whereas 16-day-old rats show no significant decrease in HR during the same period. These results suggest that the adult rats become less fearful of the test environment over time, but that the 16-day-olds maintain a high level of fear throughout the 90-min test period. Twenty-three- and 30-day-old rats show an adultlike pattern of adaptation to the unfamiliar environment, i.e., their heart rates return partially but not completely to baseline levels within the 90-min session. When an anesthetized lactating dam is present in the test environment, a strikingly different pattern of results is obtained. Heart rate in the 16-day-old rat is immediately reduced to near baseline levels whereas in the young adult (60-day-old) rat the presence of the anesthetized dam has no effect on either initial HR or rate of adaptation. Again the 23- and 30-day-old rats showed an intermediate pattern of adaptation. In two follow-up experiments the effects of adding (Expt. 2) or removing (Expt. 3) an anesthetized dam on the 16-day-old rats' response to an unfamiliar environment was examined. Both experiments showed that animals were more fearful when the dam was absent from the environment than when it was present.

Aging↗
PubMed1997

Locomotor sensitization to quinpirole: environment-modulated increase in efficacy and context-dependent increase in potency.

This study examines whether behavioural sensitization to the dopamine agonist, quinpirole, reflects an increase in the drug's potency and/or efficacy to induce locomotion, and how these parameters are influenced by environmental context. Three experiments were conducted in which animals received either chronic quinpirole (10 x 0.5 mg/kg, twice weekly) or saline injections in either the home cage environment, an alternate environment or the testing environment (activity monitors), followed by a dose-response test for the expression of sensitization in the activity monitors. Compared to the acute dose-response relationship, chronic quinpirole increased the maximum response. This increase in efficacy was significantly higher in animals treated with quinpirole in a non-home cage environment compared to those that received chronic treatment in the home cage. A leftward shift in the dose-effect function was observed only in animals with prior drug experience in the testing environment. Results indicate that locomotor sensitization to quinpirole reflects an environment-modulated increase in the drug's efficacy, and an environment-dependent increase in drug potency. Efficacy and potency may be subject to sensitization by non-associational and associational mechanisms, respectively.

Animals↗
PubMed1984

Effects of intensive induction chemotherapy for extensive-disease small cell bronchogenic carcinoma in protected environment-prophylactic antibiotic units.

Fifty-five patients with extensive-disease small cell bronchogenic carcinoma received three courses of intensive, inpatient, remission induction chemotherapy in (25 patients) or out (30 patients) of protected environment-prophylactic antibiotic (PEPA) units. Chemotherapy consisted of ECHO induction (E = epipodophyllotoxin VP-16-213; C = cyclophosphamide; H = hydroxydaunorubicin; O = Oncovin) and PRIME maintenance (PR = procarbazine; I = ifosfamide; ME = methotrexate). All evaluable patients (22 in the protected environment group and 26 in the control group) had a complete (50 percent in the protected environment group and 54 percent in the control group) or partial (50 percent in the protected environment group and 46 percent in the control group) remission. Median response and survival durations for both treatment groups were similar. The median survival duration of patients with a complete remission favored the protected environment group (16.5 versus 12.67 months; p = 0.20). Two patients (one from each group) are alive and disease-free for more than four years. Myelosuppression was intense and more pronounced in the protected environment group (p less than or equal to 0.01). Infectious complications were less common in patients receiving intravenous prophylactic antibiotics and in those treated with intravenous antibiotics in PEPA units (p less than or equal to 0.04). There were no treatment-related deaths, although treatment might have contributed to the death of three patients in the protected environment group and four in the control group. The administration of intensive ECHO induction chemotherapy to patients with extensive small cell bronchogenic carcinoma produced a high complete remission rate, although there was no significant long-term survival advantage over a program of less intensity. The administration of intravenous prophylactic antibiotics and the use of PEPA units significantly reduced the infectious morbidity of chemotherapy.

Adult↗
PubMed1986

The effects of postoperative physical environment on novelty seeking behaviour and maze learning in rats with hippocampal lesions.

The effects of different postoperative physical environments on novelty seeking and maze learning were tested in rats that sustained dorsal hippocampal lesions at 30 days. After surgery, rats were isolated for one month, either with objects or without objects in their cages. All rats were moved daily to new cages and observed during the first 5 min; during these periods, sham-operated rats and rats with lesions interacted similarly with their environment. At the end of the differential housing period, rats were tested for their reactions towards a novel object introduced to their familiar environment (test 1) and towards a novel environment they were free to explore or to avoid (test 2). In test 1, rats with lesions made more contacts with the novel object than did intact rats, and rats previously housed with objects, whether they sustained lesions or not, climbed on the novel object more often than rats reared without objects. In test 2, rats with lesions made no clear distinction between the novel and familiar environments irrespective of their postoperative treatment; in contrast, intact rats housed with objects differed from intact rats housed without objects in their preference for the novel and familiar environments and in the locomotor activity they displayed in these environments. Following these two tests, learning performance was assessed in an 8-arm radial maze. Rats with lesions made more errors than the intact rats, and within the rats with lesions those reared with objects tended to make fewer errors than those reared without objects.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2006

The effect of environment and task on gait parameters after stroke: A randomized comparison of measurement conditions.

OBJECTIVES: To assess the effect of environment and a secondary task on gait parameters in community ambulant stroke survivors and to assess the contribution of clinical symptoms to gait performance. DESIGN: A 2x3 randomized factorial design with 2 main factors: task (no task, motor task, cognitive task) and environment (clinic, suburban street, shopping mall). SETTING: Subjects were assessed in 1 of 3 settings: 2 in the community (a suburban street and shopping mall) and 1 clinical environment. PARTICIPANTS: Twenty-seven people with stroke (mean age, 61+/-11.6y; mean time since stroke onset, 45.8+/-34.2mo), living at home, were recruited from community stroke groups and from a local rehabilitation unit. Selection criteria included the following: ability to give informed consent, unilateral first ever or recurrent stroke at least 6 months previously, walking independently in the community, a gait speed between 24 and 50 m/min, Mini-Mental State Examination score of 24 or higher, and no severe comorbidity. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Gait speed (in m/min), cadence, and step length were assessed by using an accelerometer with adjustable thresholds. Clinical measures hypothesized to influence gait parameters in community environments were also assessed including fatigue, anxiety and depression, and attentional deficit. RESULTS: Twenty-seven people with a mean baseline gait speed of 42.2+/-5.9 m/min were randomly allocated to 1 of 9 conditions in which the setting and distraction were manipulated. Analysis of variance showed a significant main effect for environment (P = .046) but not for task (P = .37). The interaction between task and environment was not significant (P = .73). Adjusting for baseline gait speed, people walked on average 8.8m/min faster in the clinic (95% confidence interval, 0.3-17.3m/min) than in the mall. Scores for fatigue, anxiety and depression, and attentional deficit were higher than normative values but did not influence gait performance. CONCLUSIONS: This study suggests that people with chronic stroke cope well with the challenges of varied environments and can maintain their gait speed while performing a secondary task. Despite moderate levels of gait impairment, gait automaticity may be restored over time to a functional level.

Analysis of Variance↗
PubMed2005

Acute and chronic cocaine behavioral effects in novel versus familiar environments: open-field familiarity differentiates cocaine locomotor stimulant effects from cocaine emotional behavioral effects.

Cocaine is a potent stimulant drug, but its stimulant effects can be substantially modulated by environmental novelty versus familiarity. In this report, we varied exposures to a novel environment as a way to assess the impact of environmental familiarity versus novelty upon the locomotor activation induced by acute and chronic cocaine treatments. In experiment 1, the effects of 1 (PE1) versus 0 (PE0) pre-exposures to the test environment were compared for their impact upon the locomotor stimulant, central zone entry and grooming effects induced by an acute cocaine (10 mg/kg) treatment. In experiment 2, the effects of 10 (PE10) versus 0 (PE0) pre-exposures upon the cocaine effects were compared. Experiment 3 assessed the effects of nine cocaine treatments (10.0 mg/kg) initiated in a novel environment (PE0) versus familiar environment (PE10). In all experiments, cocaine had a potent locomotor stimulant effect in a novel environment, which was attenuated by environmental familiarity such that in PE10 groups, cocaine did not reliably induce an acute locomotor stimulant effect. Environmental novelty/familiarity, however, did not reliably alter cocaine effects upon central zone penetration, grooming behavior, or the neurochemical effects induced by cocaine. In the chronic treatment regimen, the PE0 group exhibited a tolerance-like decrease in locomotor activation, but the PE10 group exhibited a sensitization-like increase in locomotor activation. Despite the marked directional changes in the locomotor stimulant effects of cocaine treatments, initiated in a novel (PE0) versus familiar (PE10) environment, the same asymptotic levels of locomotor activation were achieved. In contrast, the behavioral measures of central zone activity progressively increased with repeated treatments regardless of whether the environment was initially novel (PE0) or familiar (PE10). Thus, habituation factors can profoundly alter the locomotor stimulant effects of cocaine and can induce pseudo-tolerance phenomena. In contrast, central zone activity undergoes sensitization-like effects independent of habituation state and therefore appears to represent a more fundamental behavioral effect of cocaine. In that, central zone penetration in an open-field is linked to emotional processes; this finding is of substantial importance in understanding the effects of repeated cocaine usage.

Acute Disease↗
PubMed2006

Early family environment, current adversity, the serotonin transporter promoter polymorphism, and depressive symptomatology.

BACKGROUND: Mixed evidence has suggested that homozygous carriers of the short allele (s/s) of the serotonin transporter gene-linked polymorphic region (5-HTTLPR) may be at increased risk for depression, if they have also been exposed to early or current adversity/stress. We address this debate by examining the relation of a stressful early family environment, recent adversity/stress, and the 5-HTTLPR to depressive symptomatology in a normal sample. METHODS: A nonclinical sample of 118 young adult men and women completed assessments of early family environment, recent stressful events, psychosocial resources, and psychological distress, including depressive symptomatology. The 5-HTTLPR was genotyped using a standard protocol with DNA extracted from oral fluid. RESULTS: A stressful early family environment was significantly related to depressive symptomatology. In addition, gene-by-environment (GxE) interactions were observed between the 5-HTTLPR and both early family environment and current adversity/stress. Individuals homozygous for the short allele had greater depressive symptomatology if they had experienced early or recent adversity but significantly less depressive symptomatology if they reported a supportive early environment or recent positive experiences, compared with participants with the s/l or l/l genotype. CONCLUSIONS: Early or current environment, in conjunction with the serotonin transporter polymorphism, predicts depressive symptomatology.

Adolescent↗
PubMed2005

The urban built environment and overdose mortality in New York City neighborhoods.

Accidental drug overdose continues to be a substantial cause of mortality for drug users. Characteristics of the neighborhood built environment may be important determinants of the likelihood of drug overdose mortality independent of individual-level factors. Using data from the New York City Office of the Chief Medical Examiner, we conducted a multilevel case control study using data on accidental overdose deaths as cases and non-overdose accidental deaths as controls. We used archival data from the New York City Housing and Vacancy Survey and the Mayor's Office of Operations to assess characteristics of neighborhood external (e.g. dilapidation of buildings) and internal (e.g. quality of utilities in houses) built environment. Multilevel analyses were used to assess the relations between the neighborhood built environment and the likelihood of overdose death. Six out of the eight characteristics of the external environment studied and three out of the six characteristics of the internal environment studied were significantly associated with the likelihood of fatal drug overdose in multilevel models after adjusting for individual-level (age, race, sex) and neighborhood-level (income, drug use) variables. Deterioration of the built environment, particularly the external environment, is associated with an increased likelihood of fatal accidental drug overdose. Disinvestment in social resources, psychosocial stressors, neighborhood differences in response to a witnessed overdose, and differences in vulnerability to the adverse consequences of drug use in different neighborhoods may explain the observed associations.

Adolescent↗
PubMed2006

Perceptions of the environment, physical activity, and obesity.

Obesity rates are rising rapidly across the developed and developing world. Until recently obesity research has mainly focused on biological, psychological and behavioural factors. But there is growing agreement that environmental factors play an important role as well. In this study data from the 2003 Health Survey for England (n = 14,836) were analysed from a multilevel perspective to examine (1) the associations of the perceptions of the local environment with obesity, self-rated health, and physical activity, and (2) whether physical activity mediates the association between the perceptions of the environment, and obesity and self-rated health. This study found that perceptions of the friendliness of the local environment were mainly associated with self-rated health; perceived access to leisure facilities with sports activities; perceived access to a post office with walking; and the presence of social nuisances with obesity and poor self-rated health. In addition, positive perceptions of the social environment (i.e., social support and social capital) were associated with higher levels of physical activity, and lower levels of poor self-rated health and obesity. Only limited support was found for the idea that health behaviours mediate the associations between the perceptions of the environment, obesity, and self-rated health. Controlling for the three physical activity measures only rendered a small number of associations with self-rated health non-significant, and did not affect the associations with obesity. Overall, the results show that certain aspects of the environment may contribute to the risk of obesity and poor health. More research is needed to examine the specific mechanisms that link (the perceptions of) the environment to obesity and health.

Adolescent↗
PubMed2006

Assessing the educational environment in the operating room-a measure of resident perception at one Canadian institution.

BACKGROUND: The educational experience in the operating room is considered the centerpiece of learning for surgical residents. The educational environment is defined as the "ethos" or "climate" that affects all aspects of learning within an educational setting. A measure of the educational environment in the operating room as perceived by residents would assist educators and trainees in gauging the quality of the learning occurring within this important venue. The Operating Room Educational Environment Measure (OREEM) was adapted from an inventory validated for use with basic surgical trainees in Scotland to determine whether an inventory specifically adapted to the specialized environment of the operating room can produce a valid assessment of trainee perception of the overall educational environment and the contributing factors therein at a North American institution. METHODS: The 40-item inventory was piloted on a group of general surgery residents at the University of Calgary from November 26, 2003, to January 31, 2004. RESULTS: With a response rate of 96%, the OREEM was shown to be a relevant, internally consistent (Cronbach proportional, variant = .8656) and valid tool for assessing the overall educational environment in the operating room within a Canadian surgical residency program. Four subscales included teaching and training, learning opportunities, atmosphere, and workload/supervision/support. The overall mean score of 74% suggests the learning environment may be considered satisfactory; however, areas for potential improvement are identifiable. Results reveal strengths such as a nondiscriminatory operating room atmosphere on racial and gender grounds. However, differences were shown in male and female perceptions of learning opportunities and in junior versus senior perceptions of workload, supervision, and support. CONCLUSIONS: The OREEM has potential to be applied further as a quality assessment tool whose results could be used by faculty and program directors to improve the learning experiences of residents in the operating room.

Canada↗
PubMed2006

Impact of preschool environment upon children's physical activity and sun exposure.

BACKGROUND: The physical qualities of outdoor environments are important to trigger healthy behavior in children. We studied the impact of outdoor environments upon spontaneous physical activity and exposure to ultraviolet (UV) radiation in 4- to 6-year-old children at 11 preschools in Stockholm county. METHODS: In May-June 2004, pedometry and measurement of UV radiation were carried out on 197 children from 11 preschools in Stockholm county. Outdoor environments differed regarding vegetation, topography, space, and education. Ambient global UV radiation data were collected, free sky, and ground surface assessed. Arrival, in- and outdoor stay, and departure were recorded. For analysis, linear mixed model analysis was applied. RESULTS: In environments with trees, shrubbery, and broken ground, the mean step count/min was 21.5, and mean exposure to UV radiation as fraction of available UV during play outdoors 14.6%. In delimited environments with little vegetation, the mean step count/min was 17.7 and mean exposure fraction to UV radiation 24.3% (P < 0.001, crude). Step/min range was 8.9-30.0 (girls) and 8.8-37.2 (boys), UV radiation exposure range 4-60% (no difference between genders). CONCLUSION: Spacious preschool environments with trees, shrubbery, and broken ground trigger physical activity and yield sun protection in outdoor play. As many children attend preschool, access to such environments is recommended in community architecture.

Child↗