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PubMedDate not supplied

Insecticide metabolism and selective toxicity.

Current research is focused on means to improve the environmental acceptability and selective toxicity of existing classes of insecticides and the search for new and species selective modes of insecticidal action. The study of species differences in metabolism and its modulation by changes in chemical structure is a vital component of this effort. The importance of metabolism is illustrated by examples from the major classes of insect control chemicals, namely organophosphorus and carbamate insecticides, DDT, pyrethroids and insect growth regulators.

Cholinesterase Inhibitors↗
PubMed2001

A general account of selection: biology, immunology, and behavior.

Authors frequently refer to gene-based selection in biological evolution, the reaction of the immune system to antigens, and operant learning as exemplifying selection processes in the same sense of this term. However, as obvious as this claim may seem on the surface, setting out an account of "selection" that is general enough to incorporate all three of these processes without becoming so general as to be vacuous is far from easy. In this target article, we set out such a general account of selection to see how well it accommodates these very different sorts of selection. The three fundamental elements of this account are replication, variation, and environmental interaction. For selection to occur, these three processes must be related in a very specific way. In particular, replication must alternate with environmental interaction so that any changes that occur in replication are passed on differentially because of environmental interaction. One of the main differences among the three sorts of selection that we investigate concerns the role of organisms. In traditional biological evolution, organisms play a central role with respect to environmental interaction. Although environmental interaction can occur at other levels of the organizational hierarchy, organisms are the primary focus of environmental interaction. In the functioning of the immune system, organisms function as containers. The interactions that result in selection of antibodies during a lifetime are between entities (antibodies and antigens) contained within the organism. Resulting changes in the immune system of one organism are not passed on to later organisms. Nor are changes in operant behavior resulting from behavioral selection passed on to later organisms. But operant behavior is not contained in the organism because most of the interactions that lead to differential replication include parts of the world outside the organism. Changes in the organism's nervous system are the effects of those interactions. The role of genes also varies in these three systems. Biological evolution is gene-based (i.e., genes are the primary replicators). Genes play very different roles in operant behavior and the immune system. However, in all three systems, iteration is central. All three selection processes are also incredibly wasteful and inefficient. They can generate complexity and novelty primarily because they are so wasteful and inefficient.

Behaviorism↗
PubMed2006

Broadening the scope on health problems among the chronically neurologically ill with the International Classification of Functioning (ICF).

PURPOSE: The aim of this study was to determine ICF items indicating health problems for patients with a chronic neurological disorder such as multiple sclerosis, Parkinson's disease and neuromuscular disease. METHOD: A Delphi study using three disease-specific panels composed of patients and proxies, medical and non-medical health professionals (N = 98). Panels were asked to select items from the International Classification of Functioning, Disability and Health (ICF) reflecting relevant disease-specific health problems. Items appraised as relevant by the panel members were compared with items in established measures namely: the Minimal Record of Disability (MRD) and the Disability and Impact Profile (DIP). RESULTS: Sixty-eight ICF items were considered to be the most relevant, and belonged to four ICF domains. No significant differences were found between the appraisal of items by patients/proxies and health professionals. Agreement across the disease panels appeared to be (very) strong. Differences between the three disease-specific panels were found for the 'Body Functions and Structures' domain: consensus was reached by extension of the inclusion criteria. The ICF-item selection covers almost all items of the established measures. The largest contrast was shown in the item selection for the 'participation' and 'environmental factors' domains. CONCLUSIONS: Selected items indicate a broader scope in studying health problems compared with widely used health status measures in neurology, especially for the ICF domains 'Participation' and 'Environmental Factors'.

Chronic Disease↗
PubMed2006

Isolation of Salmonella from environmental samples collected in the reptile department of Antwerp Zoo using different selective methods.

AIMS: To evaluate the environmental spread of Salmonella strains in the reptile department of Antwerp Zoo and to compare different isolation methods for Salmonella. METHODS AND RESULTS: One hundred environmental samples were collected in the service sections and public spaces of the reptile department. After pre-enrichment in buffered peptone water (BPW), selective enrichment was performed in Rappaport Vassiliadis Single Component Enrichment Broth (RVS), Selenite Cystine Broth (SEL) and Mueller Kauffman Tetrathionate Broth (MKTTn). Subculturing on Modified Semisolid Rappaport-Vassiliadis (MSRV) Medium, and the combined use of immunomagnetic separation (IMS) and RVS was evaluated. The isolation media used were Hektoen Enteric Agar (HE), Phenol Red Brilliant Green Agar (BG) and Xylose Lysine Decarboxylase Agar (XLD). Salmonella strains were found in 47 samples (47.0%). Most isolations were made on HE after combined IMS/RVS enrichment. Sixty-six Salmonella strains were serotyped, 29 belonged to Salmonella enterica ssp. enterica (I), 3 to ssp. salamae (II), 29 to ssp. arizonae or diarizonae (IIIa/b), 4 to ssp. houtenae (IV) and 1 strain showed autoagglutination. In addition, a 10-year survey (1995-2004) of Salmonella serovars isolated from reptiles at Antwerp Zoo is presented. CONCLUSIONS: A high prevalence of Salmonella strains was noted in the service sections of the reptile department. Only a few isolations were made in the public spaces. Selective enrichment in RVS was the most efficient. In combination with IMS, this method gave an even higher isolation rate than the International Standard method (ISO 6579:2002). SIGNIFICANCE AND IMPACT OF THE STUDY: This study confirms the importance of reptiles as spreaders of Salmonella in their surroundings. The possible infectious risks for zoo personnel and visitors are evaluated. Improved laboratory protocols for the isolation of Salmonella from the environment are suggested.

Animals↗
PubMedDate not supplied

[The ability to extrapolate the direction of movement in mice selected for large and small brain weight: the influence of environmental enrichment].

Female mice from the strains selected for large and small brain weight (LB, SB) were kept either in "enriched" or in standard laboratory environment for 3 months. At the end of this period they were tested in the open field and for the ability to extrapolate the direction of the food stimulus movement. Scores of the LB mice kept in the "enriched" environment were significantly higher in the extrapolation test as compared to the LB mice kept in the standard environment as well as to the SB mice of both groups.

Animals↗
PubMedDate not supplied

A longitudinal investigation of selected pesticide metabolites in urine.

As part of a longitudinal investigation of environmental exposures to selected chemical contaminants, concentrations of the pesticide metabolites 1-naphthol (INAP), 3,5,6-trichloro-2-pyridinol (TCPY), malathion dicarboxylic acid (MDA), and atrazine mercapturate (AM) were measured in repeated samples obtained from 80 individuals in Maryland during 1995-1996. Up to six urine samples were collected from each individual at intervals of approximately 8 weeks over a 1-year period (i.e., one sample per participant in each of six cycles). INAP (median=4.2 microg/l and 3.3 microg/g creatinine) and TCPY (median=5.3 microg/l and 4.6. microg/g creatinine) were present in over 80% of the samples, while MDA and AM were detected infrequently (6.6% and <1% of samples, respectively). Geometric mean (GM) concentrations of INAP in urine did not vary significantly among sampling cycles. In contrast, GM concentrations of TCPY were significantly greater in samples collected during the spring and summer of 1996 than in the preceding fall and winter. Repeated measurements of INAP and TCPY from the same individual over time were highly variable. The average range of INAP and TCPY concentrations from the same individual were approximately 200% and 50% greater than the respective population mean levels. Geometric mean (GM) TCPY concentrations differed significantly between Caucasian (n=42, GM=5.7 microg/g creatinine) and African-American (n=11, GM=4.0 microg/g) participants and among education levels, but were not significantly different among groups classified by gender, age, or household income. In future research, environmental measurements of the parent compounds and questionnaire data collected concurrently with the biomarker data will be used to characterize the determinants of variability in the urinary pesticide metabolite levels.

Adolescent↗
PubMed2004

Genetic and environmental (inter)actions in male mouse lines selected for aggressive and nonaggressive behavior.

The purpose of this study was to investigate the effects of genetic and environmental factors, as well as their interaction, in the etiology of aggressive behavior in two mouse lines bidirectionally selected for offensive aggression. To this end, we raised the Finnish TA (aggressive) and TNA (nonagressive) selection lines either in isolation or in cohabitation with a female after weaning. At the age of 3 months we determined their aggressive behavior in three paradigms (intruder resident, neutral cage, resident intruder) against a male standard opponent. We also determined the animals' aggressive behavior against a female mouse. The results show genetic and environmental effects, as well as gene-environment interaction. We see prominent genotype effects under all conditions but each test is sensitive to a specific combination of environmental effects. A particularly noteworthy result is that variation in the unusual behavior of aggression towards a female is largely explained by the interaction of genotype with isolation. We also examined whether test experience influenced the outcome of an encounter between an experimental animal and an opponent, and found that this factor should not be underestimated, its effect size and direction depending on the type of paradigm and way of housing. These data suggest that the identification of genes underlying aggressive behavior in mice is by no means straightforward and that the result of this search will depend on the environmental design of the study (type of paradigm, housing conditions). These data also suggest that the use of 'test battery' mice might produce different results than the use of test-naïve animals.

Aggression↗
PubMed2006

Selecting earlywood vessels to maximize their environmental signal.

The anatomical features of earlywood vessels often reflect information about past climatic conditions. We examined the relationships between mean monthly temperature and mean vessel lumen area (MVA) in various categories of earlywood vessels. Subsets of earlywood vessels of chestnut (Castanea sativa Mill.) were selected from a previously reported dataset based on several progressive size-related procedures. To include all earlywood vessels, the minimum size considered was 10,000 microm2. Changes in the correlations between MVA and the mean air temperature in March are described and discussed. The results show that not all vessels embody the same information. The MVA of a proportion of the largest earlywood vessels in each annual ring was most closely related to March temperature, whereas MVA of the smallest earlywood vessels was better correlated with June temperature. This difference is probably a result of the vessels being formed at different times: early spring for the largest earlywood vessels and later in spring for the smallest earlywood vessels. Analyses combining large and small vessels yielded lower correlations between MVA and monthly temperature. The number, size and distribution of vessels can vary greatly from ring to ring. In making year-to-year comparisons, the best information is provided by observations on vessels of contemporaneous ontogenesis. Criteria for the selection and analysis of vessels in the assessment of temperature during the season of wood formation are proposed and discussed.

Climate↗
PubMed1999

[Studies on detection methods for Legionella species from environmental water].

We investigated selective cultivation media and previous treatments of samples suitable for detection of Legionella species from environmental water and for elimination of co-existing microbes which gave rise to an interference with the evaluation of Legionella sp. growth. Twenty thousand U of polymyxin B (PL-B)/ml and 100 micrograms of oxytetracycline (OTC)/ml seem to be useful as additives to MWY selective agar medium. Both antibiotics markedly inhibited the growth of co-existing microbes with almost no influence on the growth of Legionella sp. In the studies on the resistance of 8 strains of Legionella sp., 24 strains of co-existing microbes and 2 standard strains of Staphylococcus aureus and Escherichia coli to acid treatment (0.2 M HCl-KCl, pH 2.2, 25 degrees C, 4 minutes) and heating (50 degrees C, 20 minutes), acid treatment or heating alone showed no inhibition on the growth of almost all strains examined. However, combination with acid treatment after heating resulted in an apparent extinction of almost all microbes except for Legionella sp., Seven strains from co-existing microbes showed an apparent growth inhibition against 8 strains of Legionella sp. with different serotypes and were all identified as Pseudomonas aeurginosa, which were all eliminated by means of the combination with acid treatment after heating. From these results, it was concluded that the combined pre-treatment of water samples with acid after heating and the addition of PL-B and OTC into the selective cultivation medium is an useful method for detection of Legionella sp. from environmental water.

Anti-Bacterial Agents↗
PubMed1975

Ion-selective electrodes and enzyme electrodes in environmental and clinical studies.

Electrodes have been developed for the assay of glucose, urea, amino acids, uric acid, phosphate, nitrate and perchlorate. The electrodes for the organic compounds are enzyme electrodes which are prepared by chemically immobilizing an enzyme over the outside of a conventional ion-selective electrode. These electrodes will be discussed in depth. The progress and the development of the electrodes that show sensitivity and selectivity for phosphate, nitrate and perchlorate will be outlined. The basis of these sensors is a complex of a transition metal of either an analog of thiourea or an organic chelator, such as 1,10-phenanthraline. Such electrodes respond linearly to phosphate, nitrate or perchlorate, and show selectivity over sulphate, halides and acetate. The linear range of all these electrodes is approx. 10(-1)-10(-5) M with a near Nernstian slope and a reproducibility of 1%. The electrodes are stable and can be used continuously.

Amidohydrolases↗
PubMed2001

Solutions to health care waste: life-cycle thinking and "green" purchasing.

Health care waste treatment is linked to bioaccumulative toxic substances, such as mercury and dioxins, which suggests the need for a new approach to product selection. To address environmental issues proactively, all stages of the product life cycle should be considered during material selection. The purchasing mechanism is a promising channel for action that can be used to promote the use of environmentally preferable products in the health care industry; health care facilities can improve environmental performance and still decrease costs. Tools that focus on environmentally preferable purchasing are now emerging for the health care industry. These tools can help hospitals select products that create the least amount of environmental pollution. Environmental performance should be incorporated into the evolving definition of quality for health care.

Conservation of Natural Resources↗
PubMed1981

Measurements of environmental radiation exposure dose rates at selected sites in Brazil.

Two types of portable instruments were developed by the former Health and Safety Laboratory of the U.S. Atomic Energy Commission to characterize external gamma radiation fields and to estimate individual exposure dose rates from major natural or fission radionuclides distributed in the soil: a pressurized ionization chamber and a NaI(T1) gamma-ray spectrometer. The two instruments were used to measure environmental radiation exposure rates at three distinct geological areas of Brazil: - in the towns of Guarapari and Meaípe located on the monazite sand belt, ES. - on the vicinities of the uranium mine of Poços de Caldas, MG. - around the site of the Brazilian first nuclear power plant, in Angra dos Reis, RJ. The radiometric survey demonstrated once more the usefulness and versatility of the two instruments used. The measurements around the nuclear installations of Poços de Caldas and Angra dos Reis, allowed a rapid assessment of the local radiation background and its variability, as well as the selection of stations for the routine monitoring program. Radioactive anomalies were detected and characterized previously to the start of plant operations. The survey in Guarapari and Meaípe confirmed the results obtained by Roser and Cullen in 1958 and 1962, except on sites where considerable changes took place since then. The spectrometric measurements gave estimations of the relative proportion of 40K, 238U and 232Th series in the ground and also indications on the homogeneity of their distribution in the soil.

Brazil↗
PubMed2000

[Change in gene action, genotype ranks, and results of selection in a Johannesen populations under the effect of environmental factors].

Eight mapped mutants (er, tfl, fb, fca, fd, fe, fg, and fy) of arabidopsis (Arabidopsis thaliana (L.) Heynh.) were chosen as the model for investigation of plant response to vernalization and day length. Six quantitative characters were recorded: the number of days from sowing until flowering, plant weight, stem height, number of rosette leaves, number of cauline leaves, and total leaf number. The genotypes responded differently to environmental changes, which altered the effects of genes on quantitative traits, genotype ranks, and selection consequences. A certain set of environmental factors may result in selection in favor of one genotype, and another set may result in selection for another genotype, with direction and intensity of selection being the same.

Arabidopsis↗
PubMed2000

Determination of environmentally relevant aromatic amines in the ppt levels by cation selective exhaustive injection-sweeping-micellar electrokinetic chromatography.

Environmentally important aromatic amines are determined by micellar electrokinetic chromatography (MEKC) with UV detection. Using a combination of field-enhanced sample injection in the capillary zone electrophoresis format (performed for a longer period than usual, e.g., 200 s at high voltages; cation selective exhaustive injection) and sweeping in the MEKC format, from 10(4)- to 10(5)-fold improvements in detector response are achieved for all positively chargeable test analytes. Preliminary results indicate that limits of detection for the positively chargeable aromatic amines are in the parts per trillion (ppt) levels.

Amines↗
PubMed2006

Analysis of hexabromocyclododecane diastereomers and enantiomers by liquid chromatography/tandem mass spectrometry: chromatographic selectivity and ionization matrix effects.

Hexabromocyclododecane (HBCD) is a flame retardant that is undergoing environmental risk assessment. The liquid chromatographic retention and electrospray ionization matrix effects were investigated for HBCD methods of analysis for environmental matrices. Column selectivity towards HBCD diastereomers was evaluated for C30 and C18 stationary phases under different mobile phase conditions and column temperatures. The HBCD elution order was dependent on the shape selectivity of the stationary phase and the mobile phase composition. Greater resolution, on columns with reduced shape selectivity, of beta-HBCD and gamma-HBCD was achieved with the use of an acetonitrile/water (compared with a methanol/water) mobile phase composition. A liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) method for the analysis of HBCD in biological tissues was evaluated for potential matrix effects. The influence of extracted matrix components on HBCD diastereomer and enantiomer analysis was investigated using a postextraction addition approach. Although the analysis of HBCD diastereomers was relatively unaffected by the sample matrix, the responses of the HBCD enantiomers in tissue samples were significantly influenced by matrix effects and other changes to the ionization conditions. The use of racemic 13C-labeled HBCD diastereomers as internal standards for enantiomer fraction measurements corrected for the changes in the mass spectrometer response.

Acetonitriles↗
PubMed2000

A study of the genetic and environmental etiology of stuttering in a selected twin sample.

Stuttering is a developmental disorder of speech production that usually emerges in childhood. In this study, a large population-based twin sample from the Australian Twin Registry (1567 pairs and 634 singles aged 17-29 years) was screened to identify twin pairs in which one or both members reported themselves to be affected by stuttering. Telephone interview-based diagnoses were obtained for 457 of these individuals (self-reported affected cases, cotwins, and controls) to determine whether the self-report was correct. To correct for ascertainment bias we carried out a bivariate analysis of the final diagnosis in the selected sample with the screening item in the full sample, using the categorical raw data option of Mx 1.47c. After correcting for ascertainment bias, approximately 70% (95% confidence interval: 39-86%) of the variance in liability to stuttering was found to be attributable to additive genetic effects, with the remainder due to nonshared environmental effects.

Adolescent↗