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Human pharmaceuticals in the aquatic environment a review.

There has been increasing concern in recent years about the occurrence, fate and toxicity of pharmaceutical products in the aquatic environment. Many of the more commonly used drug groups (for example antibiotics) are used in quantities similar to those of pesticides and other organic micropollutants, but they are not required to undergo the same level of testing for possible environmental effects. The full extent and consequences of the presence of these compounds in the environment are therefore largely unknown and the issue as a whole is ill-defined. Although these compounds have been detected in a wide variety of environmental samples including sewage effluent, surface waters, groundwater and drinking water, their concentrations generally range from the low ppt to ppb levels. It is therefore often thought to be unlikely that pharmaceuticals will have a detrimental effect on the environment. However, the lack of validated analytical methods, limited monitoring data and the lack of information about the fate and toxicity of these compounds and/or their metabolites in the aquatic environment makes accurate risk assessments difficult.

Germany↗

Accessibility to the public environment as perceived by teenagers with functional limitations in a south Swedish town centre.

PURPOSE: Owing to physical inaccessibility persons with mobility restrictions and other functional limitations often face problems in public environments, leading to restrictions in activity and participation. To investigate general accessibility and perceived problems of accessibility to the public environment in a town centre, as well as visiting preferences to public facilities, among teenagers with functional limitations. METHODS: An interview questionnaire specific to a south Swedish town was constructed and used with 33 Swedish teenagers with functional limitations. RESULTS: To a varying degree, all 33 teenagers commented on accessibility problems, e.g. concerning uneven surface material outdoors, steps at entrances, heavy doors and restricted space indoors. The results also indicated that teenagers with functional limitations to a high extent want to visit the same environments as other teenagers, but that it is often impossible owing to accessibility problems. Furthermore, because of accessibility problems, many of the teenagers were dependent on personal assistance. CONCLUSION: Inaccessibility results in dependence, which might affect personal development negatively, and much effort are required in order to ensure activity and societal participation. Efficient priorities in public environment accessibility matters and discussions with the actors involved require valid and reliable data on local accessibility problems.

Adolescent↗

The regulatory environment past and future--incentive or impediment to developments in food science and technology: a perspective from FDA.

The best system for protecting public health is one that involves two layers of control before food reaches the consumer. The first layer of control is the industry's clear responsibility to prepare food that is safe. The second layer of control is the monitoring that is provided by government to ensure that the industry is doing its job and is in fact producing safe food. While some may view this "second layer" as an impediment in the development and marketing of new technologies, there is another way to look at the "regulatory environment". The regulatory environment itself, is not an impediment to the development of food science and technology. The regulatory environment, with all its components--scientists, consumers, industry, and Congress--defines "safety" within the context of today's technology, scientific capability, and tolerance level of the lay public. The entire regulatory environment serves to guide the development of food science and technology by providing signposts, in the form of scientifically sound regulatory decisions. The scientific basis of these decisions becomes building blocks on which to rest further refinement of the technology, product, ingredient, or packaging material or on which research in related technologies or research in innovative directions can build. This scientific groundwork becomes very important as more and more companies move away from having self-contained research laboratories toward using commercial laboratories and academic institutions, as well as participating in cooperative research endeavors to meet food safety and product development research needs.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Total volatile organic compounds in the urban environment of Delhi.

Total volatile organic compounds (TVOCs) in the urban ambient environment of Delhi were monitored from November 1994 to June 1995 at 13 sites using an inexpensive and a manual-labor-intensive sample collection procedure in want of sophisticated equipment. The results of the study show appreciable levels of TVOCs in the ambient environment of Delhi. The amount of TVOCs in the ambient environment was found to vary between 3 and 42 ppmv and exhibited wide temporal and seasonal variations. On a diurnal cycle, TVOC levels mostly peaked at 9:00 a.m., which coincided with the peak traffic hour. TVOC buildup in the urban atmosphere has serious implications for air quality through the formation of highly toxic oxidants. The results of this preliminary study make out a strong case for a regular monitoring of TVOCs in the urban environment of Delhi.

Air Pollution↗

Thirst and work capacity of older people in a hot environment.

In a hot environment, especially during exercise, the main role of thermoregulative mechanisms is to dissipate excessive heat from the body. The most effective way of heat dissipation is sweat production and its evaporation off skin surface. Intense sweating results in a considerable loss of water and electrolytes. There are some results that indicate lower thirst of older men than young ones in response to a hot environment and osmotic stimuli. Our studies conducted in men of different ages exposed to a hot environment indicated that there were no significant differences in rectal temperature (Tre) or heat storage (S) among groups at rest. Lower Tre and lower S in older men with higher physical capacity for their age than in young ones with average physical capacity was shown. However, in all the experiments significantly lower thirst in older men than in the young was indicated. Special attention should be paid to fluid replacement among workers in a hot environment because of lower thirst and lower hydration of older men. These individuals may be exposed to dehydration risk during prolonged exercise, despite the possibility to tolerate heat strain as well as young ones. Further studies are necessary because of some diversity in the meaning of the results.

Adult↗

The safe use of automated external defibrillators in a wet environment.

UNLABELLED: There has been concern regarding potential shock hazards for rescuers or bystanders when a defibrillator is used in a wet environment and the recommended safety procedure, moving the patient to a dry area, is not followed. OBJECTIVE: To measure the electrical potentials associated with the use of an automated external defibrillator (AED) in a realistically modeled wet environment. METHODS: A raw processed turkey was used as a patient surrogate. The turkey was placed on a cement floor while pool water was applied to the surrounding area. To simulate a rescuer or bystander in the vicinity of a patient, a custom sense probe was constructed. Defibrillation shocks were delivered to the turkey and the probe was used to measure the voltage an operator/bystander would receive at different points surrounding the surrogate. The test was repeated with salt water. RESULTS: The maximum voltage occurred approximately 15 cm from the simulated patient and measured 14 V peak (current 14 mA peak) in the case of pool water, and 30 V peak (current 30 mA peak) in the case of salt water. CONCLUSIONS: Thirty volts may result in some minor sensation by the operator or bystander, but is considered unlikely to be hazardous under these circumstances. The maximum currents were lower than allowed by safety standards. Although defibrillation in a wet environment is not recommended practice, our simulation of a patient and a rescuer/bystander in a wet environment did not show significant risk should circumstances demand it.

Animals↗

Educational environment in traditional and innovative medical schools: a study in four undergraduate medical schools.

INTRODUCTION: The undergraduate curricula of medical schools in King Abdul Aziz University, Saudi Arabia, Umm Al-Qura University, Saudi Arabia and Sana'a University, Republic of Yemen are traditional, like most of the medical schools in the Middle East region. The curriculum in Dundee University Medical School, UK, claims to follow the prescriptions of the UK General Medical Council to be outcome based with three interlocking phases and students encouraged to take responsibility for their own learning. The aim of this study is to measure the educational environment, using the 50-item Dundee Ready Education Environment Measure (DREEM), in each medical school and to compare the educational environment as perceived by the responding students of the traditional medical schools in developing countries with that of the "modernised" medical school in Dundee University, UK. METHODS: The DREEM was administered to 1072 medical students in the four different universities. Using SPSS, data were expressed as means of scores. Comparisons between schools, years of study and gender were made using non-parametric tests. RESULTS: For all three traditional medical schools, the mean scores of the inventory were lower compared with Dundee Medical School. Students from traditional schools rated their learning and teaching environment significantly lower than their counterparts in Dundee Medical School. Similarly, they rated their academic self-perceptions, social-self perceptions and their atmosphere more poorly than the Dundee students. CONCLUSION: The DREEM provides useful diagnostic information about medical schools, whether it is in developing or western developed countries.

Adult↗

Importance of sanitary environment for growth performance and plasma nutrient homeostasis during the post-weaning period in piglets.

Deterioration of sanitary conditions in piggeries is known to limit growth performance through inducing a moderate immune response. This article reports the results of an experiment performed to reproduce the consequences of bad sanitary conditions on growth performance and nutrient plasma concentrations of piglets after weaning. We propose to use these experimental conditions as a model for studying the interactions between nutrition and pig health. In this experiment, 20 pairs of littermate piglets were selected and weaned at 28 days of age on the basis of their body weight. Within each pair, piglets were pair-fed and each one was affected to one of the two experimental groups. The first group was housed in a clean environment and was fed an antibiotic supplemented standard diet. The second group was kept in unsanitary rooms, mixed with non-experimental piglets and was fed the same standard diet but without antibiotic supplementation. Compared to pigs kept in the clean environment, piglets kept in the unsanitary environment had significantly lower rate of weight gain and feed efficiency from weaning to 20 d post weaning then from 36 - 45 d post weaning. They also displayed higher plasma concentrations of haptoglobin, copper, vitamin B12 and lysine but lower concentrations of glutathione, pyridoxal-5-phosphate, folic acid, threonine and tryptophan. Our results showed that a reduction of growth performance and a modification of nutrient utilization can be induced by decreasing the sanitary quality of environment where pigs are kept after weaning and after transition to another building. This response could be explained by a moderated activation of body defences.

Amino Acids↗

The effects of a nap opportunity in quiet and noisy environments on driving performance.

While napping has previously been shown to alleviate the effects of sleep loss, before advocating the use of naps in transport accident campaigns it is necessary to consider whether a nap opportunity in a noisy uncomfortable environment can produce the same benefits as a nap opportunity in conditions that are conducive to sleep. To examine this, eight participants drove a driving simulator for 50 min at 11:00h on three different test days. The simulator used has previously been found to be sensitive to the effects of sleep loss, alcohol consumption, and time of day. All three sessions were conducted after one night of sleep loss. Prior to driving during each session the participants either had a 60 min nap opportunity in a quiet or noisy environment, or no nap opportunity. Driving performance and reaction time while driving were measured, as were subjective sleepiness and ratings of sleep quality. No significant benefits of nap opportunities on driving performance were found. Levels of subjective sleepiness were not affected by the nap opportunity condition; however, sleep was rated as more refreshing and restful after a nap in a quiet environment compared to noisy environment. The measures of effect size reported suggest further research is required to unequivocally test the effects of nap opportunities on driving ability.

Accidents, Traffic↗

Animals, energy, and water in extreme environments: perspectives from Ithala 2004.

Animals occupy an impressive range of environments, and many approach the limits of conditions that are compatible with life. Such environments are often characterized by low productivity, and survival depends on abilities to maintain levels of hydration sufficient for biochemical reactions and an adequate level of energy turnover. Specific adaptations for acquiring and conserving water affect the intake and utilization of energy that is available for growth and reproduction. Almost any benign, historically stable environment can become hostile if conditions change, and the severity of challenges to animals depends on temporal as well as spatial factors that are related to the intensity and duration of harsh conditions (e.g., drought). Animals have responded to such changes through avoidance, phenotypically plastic adjustments, and evolutionary changes in genomic structure. Here we present an overview of research findings presented at a session of the Third International Conference of Comparative Physiology and Biochemistry. We hope such a synthesis will stimulate new directions in research that address biological responses to environmental change. In this context, we believe that challenging environments in Africa might provide increasingly useful sites for biological investigations relating to the application of comparative and evolutionary approaches toward a deeper understanding of physiological adaptation.

Acclimatization↗

Biomagnetometers for unshielded and well shielded environments.

The paper describes magnetometers for operation in well shielded and unshielded environments. For unshielded environments, the noise cancellation is accomplished by spatial filtering using higher-order gradiometers which are formed in software. The theory of the software formation of high-order gradiometers has been successfully tested experimentally to the second-order gradient level, using a seven-channel prototype system. An unshielded, open environment system, designed to operate with third-order noise cancellation is presently under construction. It is a whole head system, consisting of a minimum of 64 sensing channels, and is expected to be operational by late 1991. In the opposite extreme, a magnetometer is being developed for operation in a well shielded environment of a whole body superconducting shield. The high temperature superconducting shield will operate in liquid nitrogen, while the magnetometer detection system will operate in liquid helium. The high level of shielding will allow detection of biomagnetic signals using magnetometers. The whole body high temperature superconducting shielded system is presently under development and a half scale working shield already exists. The complete whole body shielded system is expected to be operational in 1994/95.

Equipment Design↗

Radioactivity in food and the environment: calculations of UK radiation doses using integrated assessment methods.

A new method for estimating radiation doses to UK critical groups is proposed for discussion. Amongst others, the Food Standards Agency (FSA) and the Scottish Environment Protection Agency (SEPA) undertake surveillance of UK food and the environment as a check on the effect of discharges of radioactive wastes. Discharges in gaseous and liquid form are made under authorisation by the Environment Agency and SEPA under powers in the Radioactive Substance Act. Results of surveillance by the FSA and SEPA are published in the Radioactivity in Food and the Environment (RIFE) report series. In these reports, doses to critical groups are normally estimated separately for gaseous and liquid discharge pathways. Simple summation of these doses would tend to overestimate doses actually received. Three different methods of combining the effects of both types of discharge in an integrated assessment are considered and ranked according to their ease of application, transparency, scientific rigour and presentational issues. A single integrated assessment method is then chosen for further study. Doses are calculated for surveillance data for the calendar year 2000 and compared with those from the existing RIFE method.

Food Contamination, Radioactive↗

Conceptualization and evaluation of an optimal healing environment for chronic low-back pain in primary care.

This paper describes what a primary care-based optimal healing environment (OHE) might look like for chronic low-back pain, and presents a research protocol to evaluate the effect of such an environment on a variety of important patient and clinician outcomes. Such an environment may be conceived of as having three major components: (1) the health care environment in which the primary care team works; (2) the cognitive, technical, clinical and organizational skills of the team, and; (3) the "healing" skills of the team members, particularly the primary care physician. A variety of study designs available for evaluating the effects of an OHE on patient and clinical outcomes are described. Decisions about study site and population, appropriate outcome measures, required sample sizes, methods of patient recruitment, treatment protocol and analytic issues would need to be tailored to the specific requirements of the study. Because many elements of an OHE designed for chronic back pain seen in primary care settings would also be relevant for the other 98% of primary care visits, it is preferable to design, implement and evaluate an OHE for primary care practice in general than for only a specific condition.

Clinical Protocols↗

Studying optimal healing environments: challenges and proposals.

The concept of optimal healing environments has strong face validity, but it is difficult to operationalize the complexity of the human dimensions that comprise the process of healing. Only rigorous evidence can justify the tremendous resources necessary to create optimal healing environments. This article outlines the current challenges of studying optimal healing environments from a clinical epidemiology perspective and discusses the major potential obstacles to include human resources, relationship-centered care competencies, dysfunctional educational and health care systems, research competencies, credibility, dispersed and unfocused current evidence base, and the actual logistical methodological difficulties. The concept of optimal healing environments is a paradigm shift in the delivery and study of medical care, and such an initiative will likely take decades to transition. However, there are feasible activities that can currently be undertaken to expedite this transition, chief of which is establishing a coalition of influential societies to forge an agenda on several fronts. Research activities presently should focus on validating and simplifying measurement tools for healing-related outcomes constructs, expanding the versatility and use of qualitative methods, as well as synthesizing research evidence to help clarify the current evidence base and the future research agenda.

Chronic Disease↗

The physicochemical environment of the neonatal intestine.

Dietary intake, bacterial metabolites, and the secretion of factors (eg, proteins, electrolytes, lipid-soluble molecules, and water) by the body each contribute to the physicochemical environment of the gastrointestinal tract. Peristalsis regulates the changes along the length of the intestine. However, coordinated peristaltic responses develop as premature infants mature. In addition, the physicochemical environment of the center of the intestinal lumen differs from that of the epithelial surface. The area adjacent to the small intestinal epithelium is more acid than the bulk phase. Na+/H+ exchange antiporters in the epithelial cell apical membrane generate this acidity. Mucus maintains the acid microclimate by preventing free diffusion of hydrogen ions into the bulk phase. Development also affects these mechanisms. Changes in the lumenal environment may alter the synthesis of signaling molecules expressed by the intestinal epithelium. Thus, the epithelium, through changes in gene regulation, may act as an active interface that transmits information about the composition of the intestinal lumen to the mucosal immune system. Premature neonates are at risk of necrotizing enterocolitis, a disease almost exclusively associated with oral feeds. The pathogenesis of this condition may, in part, be due to the immaturity of the interactions between the physicochemical environment of the lumen and intestine.

Cytokines↗

Flexible matching strategies to increase power and efficiency to detect and estimate gene-environment interactions in case-control studies.

Lack of power is a pertinent problem in many case-control studies of gene-environment interactions. The authors recently introduced the concept of flexible matching strategies with varying proportions of a matching factor among selected controls (degree of matching) to increase the power and efficiency of case-control studies. In this study, they extended the concept of flexible matching strategies to the field of gene-environment interactions. They assessed the power and efficiency of such studies to detect and estimate gene-environment interactions under a variety of assumptions regarding the prevalence and effects of the environmental exposure and the genetic susceptibility as well as their association in the population. For each set of parameters, 10,000 case-control studies were simulated using varying degrees of matching. Traditional frequency matching increased the power and precision in most scenarios, but even greater gains were often obtained by increasing the prevalence of the environmental exposure in controls above the one in cases. The authors concluded that flexible matching strategies can increase the power and efficiency of case-control studies to detect and estimate gene-environment interactions compared with traditional frequency matching and therefore might help to alleviate the notorious lack of power of these studies in specific situations.

Case-Control Studies↗

Arbor 3D: an interactive environment for examining phylogenetic and taxonomic trees in multiple dimensions.

UNLABELLED: This paper examines a new technique for the visualization of and the interaction with trees, objects frequently used to convey hierarchical relationships in biological data. Motivated by the quality of 2D tree interaction, we adapt the planar tree-of-life metaphor to a virtual, semi-immersive 3D environment. A 3D environment extends the utility of this metaphor by allowing the user to view an entire data set in a single screen. Interrogation of the tree is implemented using 3D input devices. This real-time interrogation of the tree itself provides a quick means by which to qualitatively analyse the hierarchical data. In this paper, we describe the techniques underlying the implementation of such an environment. We conclude by considering the utility of tree metaphors as a basis for the representation of highly dimensional data sets. AVAILABILITY: Arbor3D (source code, a binary executable for SGI IRIX 6.4, Perl parsers, and sample Newick data files) are available via the Internet (http://xian.tamu.edu/Arbor3D/). Arbor3D can be displayed in "CAVE simulator" mode on an SGI workstation screen, or as an interactive virtual environment on a projection workbench. CONTACT: druths@rice.edu; echen@cs.rice.edu; leland@xian.tamu.edu

Classification↗

Gene-environment interaction between an aldehyde dehydrogenase-2 (ALDH2) polymorphism and alcohol consumption for the risk of esophageal cancer.

Aldehyde dehydrogenase-2 (ALDH2) degrades acetaldehyde metabolized from ethanol. Its encoding gene ALDH2 has a functional polymorphism: ALDH2 Glu487LYS: An association between this polymorphism and esophageal cancer among alcoholics has been reported. To further evaluate the gene-environment interaction, a hospital-based case-control study was conducted. Cases were 102 patients with histologically confirmed esophageal cancer and controls were 241 non-cancer outpatients of Aichi Cancer Center. ALDH2 genotypes were examined by a PCR-CTPP method developed in our laboratory, which does not require a digestion stage. Logistic regression analysis was employed for estimation of relative risk and gene-environment interaction. The allele frequency for ALDH2 Lys487 was 0.28, consistent with previous reports. The age, sex, smoking and drinking status adjusted odds ratio for the ALDH2 Glu/Lys and Lys/Lys genotypes as compared with the Glu/Glu genotype was 3.43 (95% CI 1.74-6.75). The odds ratio for heavy drinking was 49.6 (14.5-169.4) among Lys487 carriers and 7.84 (2.77-22.2) for the Glu/Glu genotype. The gene-environment interaction between alcohol drinking and the ALDH2 Lys487 allele was 6.84 (2.39-19.6), whereas no significant interaction was obtained with smoking status. Although limited because of its prevalent case-control design, our study revealed a strong gene-environment interaction between ALDH2 polymorphism and heavy alcohol consumption. Taking the observed high risk of esophageal cancer in association with the ALDH2 Lys487 allele into consideration, reducing alcohol intake may be most protective among Lys487 allele carriers of this polymorphism.

Adult↗