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1.
Int J Syst Evol Microbiol ; 70(5): 3534-3540, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32375937

RESUMEN

Seven strains of an unidentifiable Corynebacterium species recovered from blood cultures, urine or cerebrospinal fluid over 26 years, closest to but differentiated from Corynebacterium imitans by 16S rRNA gene and partial rpoB gene sequencing, were studied. In November 2017, Atasayar et al. described a blood culture isolate as Corynebacterium gottingense sp. nov., which had >99 % similarity by 16S rRNA gene sequencing to the Canadian strains. In January 2018, Jani et al. described Corynebacterium godavarianum sp. nov., recovered from the Godavari River, India, which also had >99 % similarity by 16S/rpoB sequencing to the Canadian strains and C. gottingense. In May 2018, Wei et al. described Corynebacterium hadale recovered from hadopelagic water; this too had >99 % similarity by 16S rRNA gene sequencing to C. gottingense, C. godavarianum and the Canadian strains. C. gottingense DSM 103494T and C. godavarianum LMG 29598T were acquired and whole genome sequencing was performed (not previously done). Results were compared with genomes from C. hadale (GenBank accession NQMQ01) and the Canadian isolates. We found that these ten genomes formed a single taxon when compared using digital DNA-DNAhybridization, average nucleotide identity using blastn and average amino acid identity criteria but exhibited some subtle biochemical and chemotaxonomic differences. Heuristically, we propose that C. godavarianum and C. hadale are later heterotypic synonyms of, and the Canadian isolates are identifiable as, C. gottingense. We provide an emended description of Corynebacterium gottingense Atasayar et al. 2017; genomes ranged from 2.48 to 2.69 Mb (C. gottingense DSM 103494T, 2.62 Mb) with G+C content of 65.1-65.6 mol% (WGS), recovered from clinical and environmental sites.


Asunto(s)
Corynebacterium/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , Canadá , ADN Bacteriano/genética , Genes Bacterianos , Humanos , India , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
2.
Int J Syst Evol Microbiol ; 70(1): 83-88, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31596191

RESUMEN

Auritidibacter ignavus is a Gram-stain-positive bacillus derived from otorrhea. Four strains derived from ear discharges in Canada and Switzerland, with features consistent with but distinguishable from Auritidibacter ignavus IMMIB L-1656T (accession number FN554542) by 16S rRNA gene sequencing (97.5 % similarity), were thought to represent a novel species of the genus Auritidibacter. Auritidibacter ignavus DSM 45359T (=IMMIB L-1656T) was acquired to compare with Canadian and Swiss strains by whole-genome sequencing (WGS). Unexpectedly, those isolates were observed to be consistent with A. ignavus DSM 45359T by WGS (ANIb scores >98 %), MALDI-TOF (Bruker), cellular fatty acid analysis and biochemically (some differences were observed). A nearly full 16S rRNA gene sequence could not be readily prepared from A. ignavus DSM 45359T, even after multiple attempts. A 16S rRNA gene chimeric consensus sequence created from the genome assembly of A. ignavus DSM 45359T had only 97.5 % similarity to that of A. ignavus IMMIB L-1656T, implying that 16S rRNA sequence accession number FN554542 could not be replicated. We concluded that our isolates of members of the genus Auritidibacter were consistent with A. ignavus DSM 45359T, did not represent a novel species, and that the sequence corresponding to FN554542 was not reproducible. By WGS, A. ignavus DSM 45359T had genome of 2.53×106 bp with a DNA G+C content of 59.34%, while genomes of Canadian and Swiss isolates ranged from 2.47 to 2.59×106 bp with DNA G+C contents of 59.3-59.52 %. A. ignavus NML 100628 (=NCTC 14178=LMG 30897) did not demonstrate a rodcoccus cycle. Emendation of Auritidibacter ignavus was proposed based on these results.


Asunto(s)
Micrococcaceae/clasificación , Filogenia , Anciano , Técnicas de Tipificación Bacteriana , Composición de Base , Canadá , ADN Bacteriano/genética , Oído/microbiología , Ácidos Grasos/química , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suiza
3.
Can Commun Dis Rep ; 45(11): 296-301, 2019 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-31755876

RESUMEN

BACKGROUND: Increasingly, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) has been used to provide rapid, inexpensive and precise identification of bacteria, including Corynebacterium species. Only three Corynebacterium species are able to produce diphtheria toxin (DT), and strains recovered may be either toxin-producing or non-toxin-producing. It appears the more precise bacterial identification provided by MALDI-TOF systems has led to an increase in requests submitted to the National Microbiology Laboratory (NML) for toxin testing. OBJECTIVE: To describe the number of isolates identified as C. diphtheriae, C. ulcerans and C. pseudotuberculosis, submitted to the NML between January 2006 and July 30, 2019, including their geographic area, source, and whether they produce DT. METHODS: Referrals to the NML of human or animal isolates that were identified as any of those three Corynebacterium species were studied with respect to province, source and toxigenicity. Species identification was confirmed and then specimens were tested by polymerase chain reaction for the presence of tox genes and, if positive, for expression of DT by the modified Elek method. Analysis was descriptive. RESULTS: Over the study period, 639 isolates were identified as C. diphtheriae, 22 isolates as C. ulcerans; no isolates were identified as C. pseudotuberculosis. There was an increase in C. diphtheriae referrals for DT testing: from eight per year in 2006 to an average of 15 per month in 2019, or a 1,200% increase over the 13.6-year period. The referrals were primarily from western Canada (n=609/639; 95%). Most (638/639, 99%) were human isolates and most were obtained from cutaneous sites. Of those isolates, 87/639 (13.6%) were found to be toxigenic and 552/639 (86.4%) non-toxigenic. Among C. ulcerans referrals, 17/22 (77%) were from humans and five (23%) were from animals, with 10/22 (45%) being toxigenic. CONCLUSION: There has been a marked increase in referrals to the NML for DT testing of Corynebacterium species. This could be due to the enhanced ability to identify these bacteria using MALDI-TOF systems. Ongoing monitoring will help to assess whether the increase is due solely to increased precision of diagnosis or whether these are emerging cutaneous pathogens.

4.
Sci Rep ; 7(1): 2489, 2017 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-28559568

RESUMEN

Auxin plays a pivotal role in virtually every aspect of plant morphogenesis. It simultaneously orchestrates a diverse variety of processes such as cell wall biogenesis, transition through the cell cycle, or metabolism of a wide range of chemical substances. The coordination principles for such a complex orchestration are poorly understood at the systems level. Here, we perform an RNA-seq experiment to study the transcriptional response to auxin treatment  within gene groups of different biological processes, molecular functions, or cell components in a quantitative fold-change-specific manner. We find for Arabidopsis thaliana roots treated with auxin for 6 h that (i) there are functional groups within which genes respond to auxin with a surprisingly similar fold changes and that (ii) these fold changes vary from one group to another. These findings make it tempting to conjecture the existence of some transcriptional logic orchestrating the coordinated expression of genes within functional groups in a fold-change-specific manner. To obtain some initial insight about this coordinated expression, we performed a motif enrichment analysis and found cis-regulatory elements TBX1-3, SBX, REG, and TCP/site2 as the candidates conferring fold-change-specific responses to auxin in Arabidopsis thaliana.


Asunto(s)
Arabidopsis/genética , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/genética , Arabidopsis/efectos de los fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/genética , Ácidos Indolacéticos/farmacología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Pliegue de Proteína/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética
5.
Eur J Trauma Emerg Surg ; 43(1): 121-127, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26510941

RESUMEN

PURPOSE: Age is a risk factor for death, adverse outcomes, and health care use following trauma. The American College of Surgeons' Trauma Quality Improvement Program (TQIP) has published "best practices" of geriatric trauma care; adoption of these guidelines is unknown. We sought to determine which evidence-based geriatric protocols, including TQIP guidelines, were correlated with decreased mortality in Pennsylvania's trauma centers. METHODS: PA's level I and II trauma centers self-reported adoption of geriatric protocols. Survey data were merged with risk-adjusted mortality data for patients ≥65 from a statewide database, the Pennsylvania Trauma Systems Foundation (PTSF), to compare mortality outlier status and processes of care. Exposures of interest were center-specific processes of care; outcome of interest was PTSF mortality outlier status. RESULTS: 26 of 27 eligible trauma centers participated. There was wide variation in care processes. Four trauma centers were low outliers; three centers were high outliers for risk-adjusted mortality rates in adults ≥65. Results remained consistent when accounting for center volume. The only process associated with mortality outlier status was age-specific solid organ injury protocols (p = 0.04). There was no cumulative effect of multiple evidence-based processes on mortality rate (p = 0.50). CONCLUSIONS: We did not see a link between adoption of geriatric best-practices trauma guidelines and reduced mortality at PA trauma centers. The increased susceptibility of elderly to adverse consequences of injury, combined with the rapid growth rate of this demographic, emphasizes the importance of identifying interventions tailored to this population. LEVEL OF EVIDENCE: III. STUDY TYPE: Descriptive.


Asunto(s)
Geriatría/normas , Evaluación de Procesos y Resultados en Atención de Salud , Heridas y Lesiones/mortalidad , Anciano , Protocolos Clínicos , Femenino , Humanos , Masculino , Pennsylvania/epidemiología , Guías de Práctica Clínica como Asunto , Centros Traumatológicos
6.
Orig Life Evol Biosph ; 44(3): 169-74, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25515345

RESUMEN

The influence of complex dust composition on the general chemical evolution of a prestellar core and the content of complex organic compounds is studied. It is shown that various component groups respond differently to the presence of a small dust population. At early stages the difference is determined primarily by changes in the balance of photo processes due to effective absorption of ultraviolet photons by small dust grains of the second population and collisional reactions with dust particles. At later stages differences are also caused by the growing dominance of additional reaction channels related to surface organic synthesis.


Asunto(s)
Polvo Cósmico/análisis , Exobiología , Compuestos Orgánicos/análisis , Fotones , Estrellas Celestiales/química , Evolución Química , Procesos Fotoquímicos , Rayos Ultravioleta
7.
J Clin Endocrinol Metab ; 97(1): 163-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22013102

RESUMEN

CONTEXT: Epimers have identical molecular structure but differ in stereochemical configuration. It is widely believed that the C-3 epimer of 25-hydroxyvitamin D(3) [3-epi-25(OH)D(3)] is found only in neonates. However, this epimer was recently detected in a limited number of adults. The physiological importance of 3-epi-25(OH)D(3) is uncertain but might affect 25-hydroxyvitamin D test results and thereby reliability of the 25-hydroxyvitamin D(3) [25(OH)D(3)] measurement. OBJECTIVE: This project describes development of a highly sensitive method for 3-epi-25(OH)D(3) measurement and establishes the prevalence of this epimer in adult clinical serum specimens. DESIGN, SETTING, PARTICIPANTS, AND MAIN OUTCOME MEASURE: Serum 25(OH)D(3), 3-epi-25(OH)D(3), and 25(OH)D(2) concentrations were determined in a cohort of patients (n = 214; age neonate to 80+ yr). High-performance liquid chromatography with ultraviolet detection and high-performance liquid chromatography tandem mass spectrometry with atmospheric pressure chemical ionization equipped with cyanopropyl analytical columns were used to baseline separate and quantitate 25(OH)D(3), 3 epi-25(OH)D(3), and 25(OH)D(2). RESULTS: The C-3 epimer was detected in 212 of 214 (99%) of samples. Concentrations ranged from 1 to 93 ng/ml for 25(OH)D(3) and 0.1 to 23.7 ng/ml for 3-epi-25(OH)D(3). The relative amounts of epimer to 25(OH)D(3) ranged from 0 to 25.5% (mean 4.75%). The epimer amount increased as 25(OH)D(3) increased in a nonlinear mode. In sera with approximately the same 25(OH)D(3) concentration, the ratio of epimer to 25(OH)D(3) varied, e.g. at 25(OH)D(3) values of 20-22 ng/ml, the ratio varied from 2-8.5%. CONCLUSION: 3-Epi-25(OH)D(3) is present in the majority of human serum specimens. Although this concentration is generally low, further work must investigate the impact of 3-epi-25(OH)D(3) on the various 25-hydroxyvitamin D assays and ultimately what information, if any, C-3 epimer measurement can provide clinically.


Asunto(s)
Calcifediol/sangre , Calcifediol/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Análisis Químico de la Sangre/métodos , Calcifediol/análisis , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Estudios de Cohortes , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estereoisomerismo , Espectrometría de Masas en Tándem , Adulto Joven
9.
Inj Prev ; 15(6): 409-12, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19959734

RESUMEN

OBJECTIVE: To show the feasibility of using a controlled trial to investigate the effect of alcohol on firearm use. METHODS: Randomised, blinded, placebo-controlled trial in the Firearm Usage and Safety Experiments (FUSE) Lab. Treatment subjects (male, 21-40-year-old, non-habitual drinkers, with no professional firearms training) received alcohol; control subjects received placebo alcohol. The AIS PRISim Firearm Simulator, including real pistols retrofitted to discharge compressed air cartridges that simulate firearm recoil and sound, was used to measure firearm performance. Accuracy and speed for target shooting, reaction time scenarios, and scenarios requiring judgement about when to use a gun were measured. RESULTS: 12 subjects enrolled in the trial, completing 160 training scenarios. All subjects in the alcohol arm reached target alcohol level. 33% of placebo subjects reported alcohol consumption. Mechanical malfunction of the simulator occurred in 9 of 160 (5.6%) scenarios. Intoxicated subjects were less accurate, slower to fire in reaction time scenarios, and quicker to fire in scenarios requiring judgement relative to controls. CONCLUSIONS: The feasibility of a randomised, controlled trial exploring the relationship between alcohol consumption and firearm use was shown. The hypothesis that alcohol consumption worsens accuracy and retards judgement about when to use a gun should be tested. Larger trials could inform policies regarding firearm use while intoxicated.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Armas de Fuego , Adulto , Simulación por Computador , Método Doble Ciego , Estudios de Factibilidad , Humanos , Juicio , Pruebas Neuropsicológicas , Selección de Paciente , Desempeño Psicomotor , Tiempo de Reacción , Adulto Joven
10.
Inj Prev ; 12(5): 347-50, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17018680

RESUMEN

BACKGROUND AND OBJECTIVE: Finite injury prevention resources make the establishment of prevention priorities essential. Toward this end, the US National Trauma Data Bank (NTDB) for 2000 to 2004 was accessed and four injury prevention priority scores (one previously defined and three new scores) were computed. METHODS: An injury prevention priority score (IPPS) was calculated based on the frequency of an injury mechanism and the median injury severity score. In addition, a mortality priority score (Mort-PS), a hospital charge priority score (Charge-PS), and a years of potential life lost (YPLL-PS) priority score were calculated for the 13 most common injury mechanisms. RESULTS: There was variability across the four scores, but motor vehicle traffic, firearm related, and fall injuries ranked high on all four of the priority criteria. Multiple criteria should be considered when assessing injury burden. CONCLUSIONS: The methods presented here can help prioritize injuries and support more objective public policies.


Asunto(s)
Heridas y Lesiones/prevención & control , Política de Salud , Prioridades en Salud , Humanos , Incidencia , Puntaje de Gravedad del Traumatismo , Estados Unidos/epidemiología , Heridas y Lesiones/epidemiología , Heridas y Lesiones/etiología
12.
Bone Marrow Transplant ; 35(1): 85-9, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15531904

RESUMEN

We describe a series of cases of extreme hypercholesterolemia mediated by lipoprotein X in patients with chronic graft-versus-host disease of the liver after an allogeneic bone marrow transplant. All of the patients presented with a total cholesterol in excess of 1000 mg/dl (25.9 mmol/l). At the time they were also noted to have pseudohyponatremia. Cholesterol appeared to be predominantly carried by lipoprotein X. Intrahepatic cholestasis leading to reflux of bile lipoproteins into the bloodstream and subsequent formation of protein X appears to be the mechanism underlying this phenomenon. Complications, including retinal cholesterol thromboembolism and cholesteroloma of the lung have been seen in the patient with the highest cholesterol levels. Severe hypercholesterolemia is an important, and likely more common than previously reported, long-term complication of allogeneic hematopoietic stem cell transplantation. It is important for clinicians to familiarize themselves with the diagnostic and therapeutic challenges this condition presents.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Enfermedad Injerto contra Huésped/complicaciones , Hipercolesterolemia/metabolismo , Lipoproteína X/fisiología , Hepatopatías/metabolismo , Adulto , Colestasis , Colesterol/sangre , Femenino , Humanos , Hipercolesterolemia/complicaciones , Hígado/patología , Masculino , Persona de Mediana Edad , Factores de Tiempo , Trasplante Homólogo/efectos adversos
15.
J Clin Microbiol ; 40(11): 4375-81, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12409436

RESUMEN

Nineteen new Corynebacterium species or taxa described since 1995 have been associated with human disease. We report the characteristics of 72 strains identified as or most closely resembling 14 of these newer, medically relevant Corynebacterium species or taxa, as well as describe in brief an isolate of Corynebacterium bovis, a rare pathogen for humans. The bacteria studied in this report were nearly all derived from human clinical specimens and were identified by a polyphasic approach. Most were characterized by nearly full 16S rRNA gene sequence analysis. Some isolates were recovered from previously unreported sources and exhibited unusual phenotypes or represented the first isolates found outside Europe. Products of fermentation, with emphasis on the presence or absence of propionic acid, were also studied in order to provide an additional characteristic with which to differentiate among phenotypically similar species.


Asunto(s)
Infecciones por Corynebacterium/microbiología , Corynebacterium/clasificación , Animales , Técnicas de Tipificación Bacteriana , Canadá , Bovinos , Corynebacterium/genética , Corynebacterium/crecimiento & desarrollo , Corynebacterium/aislamiento & purificación , ADN Ribosómico/análisis , Humanos , Datos de Secuencia Molecular , Fenotipo , Propionatos/metabolismo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
17.
Soc Sci Med ; 53(7): 845-63, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11522133

RESUMEN

Geographers have shown that daily activities and social networks are constrained by time-space, but there are also enabling facets or opportunities created by daily routines for accessing material and emotional resources, improving quality of life, and even challenging existing power relations. Time-geography in this paper is taken as a starting point to assess how individuals living with HIV and AIDS navigate the complex and often difficult time space contexts defining their access to services. The concept of time space windows of access is offered as a way to understand the opportunities created by daily routines and social network interaction even in highly marginalized social, economic, and political circumstances. Survey data and in-depth interviews conducted with a diverse group of persons living with HIV and AIDS are used to illustrate this conceptual argument. Results indicate that the time space characteristics of daily routines, such as frequency of activities, variety or heterogeneity in activities, and whether activities are self- or social network-oriented, serve to define the availability of temporal and spatial windows of access to services. In addition, daily routines seem to matter for specific types of services, and have a limited role to play in terms of primary medical services or those associated with basic needs. The implications of these findings for theorizing and for enhancing access to services are provided.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/psicología , Infecciones por VIH/psicología , Accesibilidad a los Servicios de Salud , Investigación sobre Servicios de Salud/métodos , Actividades Recreativas , Adulto , Femenino , Humanos , Entrevistas como Asunto , Masculino , Calidad de Vida , Apoyo Social
18.
Circulation ; 104(3): 257-62, 2001 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-11457741

RESUMEN

BACKGROUND: Human immunodeficiency virus protease inhibitors (HIV PIs) are associated with hyperlipidemia, hyperglycemia, and obesity; however, it is not known whether they increase risk of atherosclerotic vascular disease. The purposes of this study were to characterize the lipoprotein abnormalities associated with use of HIV PIs in individuals with HIV infection and to determine the pathophysiological significance of these changes by assessing their effect on endothelial dysfunction. METHODS AND RESULTS: This was a cross-sectional study of 37 adults with HIV-1 infection who were receiving antiretroviral therapy. Twenty-two were taking HIV PIs (group 1); 15 were not (group 2). Lipids and lipoproteins were measured by enzymatic techniques and nuclear magnetic resonance spectroscopic analysis. Flow-mediated vasodilation (FMD) of the brachial artery was measured by high-resolution ultrasound. Subjects in both groups were similar in regard to age, time since diagnosis of HIV infection, and CD4 cell count. Group 1 subjects had higher total cholesterol (5.68 versus 4.42 mmol/L, P=0.007) and triglyceride (4.43 versus 1.98 mmol/L, P=0.009) levels, characterized by elevated levels of IDL and VLDL. Subjects in group 1 had impaired FMD (2.6+/-4.6%), indicative of significant endothelial dysfunction. Group 2 subjects had normal FMD (8.1+/-6.7%, P=0.005). In group 1, chylomicron, VLDL, IDL, and HDL cholesterol levels predicted FMD. CONCLUSIONS: Use of HIV PIs is associated with atherogenic lipoprotein changes and endothelial dysfunction. Because these metabolic and vascular changes predispose to atherosclerosis, monitoring and treatment of dyslipidemia in patients taking these medications is warranted.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Infecciones por VIH/sangre , Inhibidores de la Proteasa del VIH/efectos adversos , Hiperlipidemias/inducido químicamente , Lipoproteínas/sangre , Adulto , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Arteria Braquial/diagnóstico por imagen , Arteria Braquial/efectos de los fármacos , Arteria Braquial/fisiopatología , Colesterol/sangre , HDL-Colesterol/sangre , Estudios Transversales , Endotelio Vascular/fisiopatología , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Hiperlipidemias/sangre , Hiperlipidemias/diagnóstico , Masculino , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Factores de Riesgo , Triglicéridos/sangre , Ultrasonografía , Vasodilatación/efectos de los fármacos
19.
Br J Health Psychol ; 6(Pt 3): 243-55, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14596725

RESUMEN

OBJECTIVES: Social behaviour was investigated as a contributor to the peer acceptance of children with chronic illness. We predicted that children with illness would receive less acceptance than children without illness, and that prosocial behaviour would improve acceptance, while aggressive behaviour would hamper it. Based upon attribution and cognitive bias theories, we also predicted that prosocial behaviour would be more beneficial and aggressive behaviour less damaging to the acceptance of children with illness compared to healthy children. DESIGN: A 3 (social behaviour: prosocial, aggressive, no information) x 2 (physical status: chronically ill, healthy) within-subjects analogue design was used. METHODS: Preadolescents (N = 149) indicated social acceptance of hypothetical children portrayed in vignettes as either chronically ill or healthy with prosocial, aggressive, or no social behaviour. A 13-item social intentions scale gauged acceptance. RESULTS: The hypotheses were supported. Although children described as ill received lower acceptance ratings than healthy children, prosocial/ill children were more accepted than aggressive/ill children. Social behaviour interacted with physical status to affect acceptance. CONCLUSIONS: Social behaviour influences the peer acceptance of hypothetical children with chronic illness. Prosocial behaviour enhances acceptance of children described with illness, while aggressive behaviour hampers it. Additionally, prosocial behaviour is more beneficial, and aggressive behaviour is less damaging for children described as ill versus healthy. The potential processes by which peers judge acceptance of children with illness are discussed.

20.
Biofouling ; 15(1-3): 141-50, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-22115299

RESUMEN

In response to increased evidence of ecosystem damage by toxic antifouling paints, many researchers have developed nontoxic silicone fouling release coatings. The fouling release capability of these Systems may be improved by adding nonbonding silicone oils to the coating matrix. This idea has been tested by comparing the adhesion strength of hard- and soft-fouling organisms on a cured polydimethylsilicone (PDMS) network to that of the same network containing free polydi-methyldiphenylsilicone (PDMDPS) oil at five exposure sites in North America and Hawaii. Fouling coverage is discussed, together with the bioadhesion data, to emphasize that although these coatings foul the fouling is easily removed. The partitioning of the incorporated oil upon exposure of the coatings to a simulated marine environment containing sediment was determined. Less than 1.1 wt% of the incorporated oil was lost from the coating over one year, and the toxicity of these coatings was shown to be minimal to shrimp and fish. Brush abrasion wear was greater for coatings containing free oil, but the modulus of elasticity was not appreciably decreased by the addition of 10wt% free oil.

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