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1.
Ecotoxicol Environ Saf ; 184: 109669, 2019 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-31536847

RESUMEN

Cotton hosts a variety of arthropod pests requiring intensive control mostly with insecticides, which in turn may impact beneficial insects and the environment. Therefore, insect control in cotton fields preconizes the use of selective insecticides that offer pest control but conserve natural enemies. In this work, we measured the impact of recommended insecticides on the abundance of predatory insects and predation upon sentinel preys in the field. Further, the survival of four key selected predatory insects of cotton ecosystem, representing chewing and sucking feeding habits and different pest species attacked [Chrysoperla externa Hagen, Eriopis connexa (Germar), Podisus nigrispinus (Dallas) and Orius insidiosus (Say)], were assessed when exposed to the dried residues of the tested insecticides. Mortality of sentinel prey caused by natural enemies was higher in areas treated with selective insecticides relative to the non-selective ones, and most of time similar to the untreated areas. Furthermore, areas treated with non-selective insecticides experienced prolonged impact between sprays depending on the insecticide applied. Seasonal abundance of predatory insects was 2× greater in fields under selective and untreated fields compared to those under non-selective recommendation. Survival of predators exposed to the dried residues of the selective insecticides pymetrozine, chlorantraniliprole, pyriproxyfen, and cyantraniliprole were greater than when exposed to the non-selective lambda-cyhalothrin, malathion, dimethoate, and thiamethoxam. Among the non-selective insecticides, malathion and dimethoate exhibited shorter residual time compared to the thiamethoxam and lambda-cyhalothrin + thiamethoxam. Therefore, the recommendation of selective insecticides provides benefits for cotton pest management by maintaining the action of the natural enemies present in the field.


Asunto(s)
Escarabajos/efectos de los fármacos , Gossypium/crecimiento & desarrollo , Heterópteros/efectos de los fármacos , Control de Insectos/métodos , Insecticidas/farmacología , Conducta Predatoria/efectos de los fármacos , Animales , Ecosistema , Modelos Teóricos
2.
Psychol Med ; 48(4): 679-691, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28780927

RESUMEN

BACKGROUND: Deficits in social cognition may be among the most profound and disabling sequelae of paediatric traumatic brain injury (TBI); however, the neuroanatomical correlates of longitudinal outcomes in this domain remain unexplored. This study aimed to characterize social cognitive outcomes longitudinally after paediatric TBI, and to evaluate the use of sub-acute diffusion tensor imaging (DTI) to predict these outcomes. METHODS: The sample included 52 children with mild complex-severe TBI who were assessed on cognitive theory of mind (ToM), pragmatic language and affective ToM at 6- and 24-months post-injury. For comparison, 43 typically developing controls (TDCs) of similar age and sex were recruited. DTI data were acquired sub-acutely (mean = 5.5 weeks post-injury) in a subset of 65 children (TBI = 35; TDC = 30) to evaluate longitudinal prospective relationships between white matter microstructure assessed using Tract-Based Spatial Statistics and social cognitive outcomes. RESULTS: Whole brain voxel-wise analysis revealed significantly higher mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) in the sub-acute TBI group compared with TDC, with differences observed predominantly in the splenium of the corpus callosum (sCC), sagittal stratum (SS), dorsal cingulum (DC), uncinate fasciculus (UF) and middle and superior cerebellar peduncles (MCP & SCP, respectively). Relative to TDCs, children with TBI showed poorer cognitive ToM, affective ToM and pragmatic language at 6-months post-insult, and those deficits were related to abnormal diffusivity of the sCC, SS, DC, UF, MCP and SCP. Moreover, children with TBI showed poorer affective ToM and pragmatic language at 24-months post-injury, and those outcomes were predicted by sub-acute alterations in diffusivity of the DC and MCP. CONCLUSIONS: Abnormal microstructure within frontal-temporal, limbic and cerebro-cerebellar white matter may be a risk factor for long-term social difficulties observed in children with TBI. DTI may have potential to unlock early prognostic markers of long-term social outcomes.


Asunto(s)
Lesiones Traumáticas del Encéfalo/fisiopatología , Lesiones Traumáticas del Encéfalo/psicología , Imagen de Difusión Tensora , Conducta Social , Sustancia Blanca/patología , Adolescente , Australia , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Niño , Cognición , Femenino , Humanos , Modelos Lineales , Estudios Longitudinales , Masculino , Análisis Multivariante , Pruebas Neuropsicológicas , Estudios Prospectivos , Teoría de la Mente , Factores de Tiempo , Sustancia Blanca/diagnóstico por imagen
3.
Child Psychiatry Hum Dev ; 49(1): 109-122, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28523378

RESUMEN

Evidence-based parenting interventions have been developed and evaluated largely with mothers. This study examined practitioner reports of rates of father attendance, barriers to engagement, organizational support for father-inclusive practice, participation in training in father engagement, and competencies in working with fathers. It also explored predictors of practitioner competence and rates of father attendance. Practitioners (N = 210) who delivered parenting interventions completed an online survey. Participants reported high levels of confidence in engaging fathers, but only one in three had participated in training and levels of father attendance in parenting interventions were low. Logistic regressions showed that high levels of practitioner competence were predicted by participation in training. Moderate levels of father attendance (vs. low levels) were predicted by greater number of years of experience while high levels of attendance (vs. low levels) were predicted by greater experience, higher levels of competence and higher levels of organizational support. The implications of the findings to informing policy and practice for enhancing father engagement are discussed.


Asunto(s)
Relaciones Padre-Hijo , Padre/psicología , Responsabilidad Parental/psicología , Competencia Profesional , Psicología/normas , Trabajadores Sociales , Encuestas y Cuestionarios , Femenino , Humanos , Modelos Logísticos , Masculino , Trabajadores Sociales/psicología
4.
Cell Death Differ ; 7(1): 48-58, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10713720

RESUMEN

In this study, we demonstrate for the first time that complement attack of target cells, in the presence of suitably high levels of serum, can induce the oligonucleosomal DNA fragmentation characteristic of apoptosis. This phenomenon requires membrane permeabilisation induced by formation of the complete membrane attack complex and relies on physiologically relevant levels of serum. TUNEL analysis detected complement mediated DNA fragmentation as early as 30 min after the addition of serum and electron microscopy confirmed that chromatin became condensed after complement attack. Various experiments implicate serum DNase I as the mediator of this DNA fragmentation. Intriguingly, membrane permeability induced by melittin gave rise to similar serum dependent DNA fragmentation. The implications of these results for the study of apoptosis in vitro and in vivo are discussed.


Asunto(s)
Apoptosis/inmunología , Proteínas del Sistema Complemento/inmunología , Animales , Cromatina , Fragmentación del ADN , Cobayas , Humanos , Células Tumorales Cultivadas
5.
Mol Immunol ; 22(7): 803-10, 1985 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3849671

RESUMEN

The ability of two univalent antibody derivatives to invoke complement-mediated lysis of guinea-pig L2C leukemic lymphocytes was investigated. The derivatives were Fab/c from rabbit IgG antibody, in which only one Fab arm is removed from the parent molecule and FabFc in which Fab gamma, from peptic digestion of sheep IgG antibody, is disulfide-bonded to the Fc gamma yielded by papain digestion of an arbitrary IgG. Antibody activity was directed against surface IgM on the target cells. Both derivatives could invoke lysis via the classical pathway in the presence of rabbit complement. Exposure of the cells to the derivatives at 37 degrees C before introducing complement yielded no protective antigenic modulation. At low complement concns the derivatives were more efficient than the parent antibodies at invoking lysis, apparently due to the fact that the derivatives do not cause modulation: it appears that cells can undergo a useful degree of modulation when confronted simultaneously by bivalent antibody and low levels of complement. The Fab/c preparations were also able to invoke lysis by guinea-pig complement. Lysis occurred under conditions where activation took place only via the classical pathway (in dilute complement) or only via the alternative pathway (in the absence of calcium ions, or in C4-deficient guinea-pig serum). The results demonstrate that there is no need for two antigen-binding Fab arms in antibody activation of either the classical or alternative complement pathways. They favour models requiring clustering of Fc regions rather than steric changes which might follow binding of antigen.


Asunto(s)
Activación de Complemento , Fragmentos Fc de Inmunoglobulinas/inmunología , Fragmentos de Inmunoglobulinas/inmunología , Inmunoglobulina G/inmunología , Animales , Línea Celular , Complemento C4/deficiencia , Factor D del Complemento/inmunología , Vía Alternativa del Complemento , Vía Clásica del Complemento , Citotoxicidad Inmunológica , Cobayas , Fragmentos Fab de Inmunoglobulinas/inmunología , Inmunoglobulina M/inmunología , Linfocitos/inmunología , Conejos
6.
Eur Psychiatry ; 30(5): 555-61, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25618445

RESUMEN

RESEARCH IN CONTEXT: Parents of children with life threatening illness or injuries are at elevated risk of distress reactions, involving symptoms of acute stress disorder, depression and anxiety. Currently, the impact of child illness factors is unclear, and to date research systematically examining the prevalence of these psychological reactions across different illness groups with an acute life threat is sparse. This is important to explore given that studies show that parent functioning impacts on the psychological adjustment and recovery of the ill child. WHAT DOES THIS STUDY ADD?: At four weeks following a child's diagnosis of a serious illness, 49-54% of parents met DSM-IV criteria for acute stress disorder, across a number of illness groups, whereas 15-27% of parents were in the moderate/severe range for depression and anxiety, and 25-31% for stress. Results from this study demonstrate that rates and severity of these psychological reactions in parents of seriously ill children do not vary according to illness type. BACKGROUND: A life threatening childhood illness/injury can lead to significant distress reactions in parents, with independent studies finding such reactions in several different illness groups. To date, there is limited research systematically comparing the prevalence of adverse parental psychological reactions across different childhood illness groups with an acute life threat. This study aimed to investigate the frequency and severity of symptoms of acute traumatic stress, depression, anxiety and general stress in parents, following admission of their child to hospital for a life threatening illness. The study also aimed to explore the relationship between these symptoms, and to determine whether they differ according to illness/injury. METHODS: Cross-sectional data from a prospective, longitudinal study are reported. Participants were 194 parents of 145 children (49 couples), admitted to cardiology (n=53), oncology (n=40) and pediatric intensive care units (n=52), for serious illnesses/injuries. Parents completed self-report questionnaires within four weeks of hospital admission. RESULTS: Rates of acute traumatic stress (P=0.262), depression (P=0.525), anxiety (P=0.453) and general stress symptoms (P=0.720) in parents were comparable across illness type, with 49-54% reaching criteria for acute stress disorder, 15-27% having clinical levels of depression and anxiety, and 25-31% for general stress. Anxiety was most strongly associated with acute traumatic stress (r=0.56), closely followed by stress (r=0.52) and depression (r=0.49), with all correlations highly significant (P<0.001). CONCLUSIONS: These findings provide evidence that the child's medical condition is not associated with parents' experience of clinically significant psychological symptoms, and emphasize the importance for health care providers to be aware of these potential psychological reactions in parents, regardless of the type of illness.


Asunto(s)
Ansiedad/epidemiología , Enfermedad Crítica/psicología , Depresión/epidemiología , Padres/psicología , Trastornos por Estrés Postraumático/epidemiología , Adulto , Ansiedad/psicología , Australia/epidemiología , Niño , Preescolar , Estudios Transversales , Depresión/psicología , Femenino , Humanos , Unidades de Cuidado Intensivo Pediátrico , Estudios Longitudinales , Masculino , Relaciones Padres-Hijo , Prevalencia , Estudios Prospectivos , Trastornos por Estrés Postraumático/psicología
7.
J Immunol Methods ; 38(3-4): 295-307, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6777432

RESUMEN

Guinea pig L2C neoplastic B-lymphocytes processed from leukaemic blood collected into EDTA as anticoagulant exhibited high affinity rosetting for EAC mouse indicator cells. Partial blocking of the C3-receptors was apparent with blood collected into heparin or citrate as anticoagulant. This could be minimized by keeping the temperature at 4 degrees C and avoided by ensuring a high final concentration of citrate (greater than or equal to 40 mM). Results from experiments in vitro suggested that receptor blocking may have been a consequence of complement activation by the L2C cells occurring via the alternative pathway. No injury to the cells was evident with any of the anticoagulants used, and their susceptibility to antibody-dependent complement-mediated lysis was independent of anticoagulant and unaffected by the irregular presence of membrane-bound C3. In experiments where the antibody-induced redistribution of L2C surface immunoglobulin was investigated, it was found that cells processed from blood collected into EDTA showed poor ability to cap and interiorize their surface immunoglobulin in comparison with cells processed from heparinized or citrated blood. Inhibition of capping was found to be dependent on the concentration of EDTA and could be avoided by collecting blood into a large volume of low molarity EDTA as opposed to a small volume of high molarity EDTA. Some practical and theoretical consequences of our observations are discussed.


Asunto(s)
Anticoagulantes , Linfocitos B/inmunología , Transformación Celular Neoplásica , Complemento C3 , Animales , Formación de Anticuerpos , Unión Competitiva , Bovinos , Recuento de Células , Separación Celular , Ácido Edético , Ácido Egtácico , Cobayas , Recubrimiento Inmunológico , Neoplasias Experimentales/inmunología , Receptores de Antígenos de Linfocitos B , Receptores de Complemento , Formación de Roseta
8.
J Immunol Methods ; 231(1-2): 169-75, 1999 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-10648936

RESUMEN

We described previously a scheme for linking functionally intact human normal Fcgamma1, via a thioether linkage emerging from its hinge, to any molecule expressing a free sulfhydryl group (SH). The scheme entails reducing the Fc to release four SH from the two inter-gamma disulfide bonds (SS) in the hinge, blocking one SH by a stochastic alkylation, restoring by SS-interchange the inter-gamma SS whose two SH are still available, and attaching a bismaleimide linker to the one remaining SH. One thereby obtains Fc with a single maleimide group (Fc-maleimide) for attachment to the SH-displaying partner. Restoration of the inter-gamma SS is necessary if the final chimeric construct is to be able to activate the classical complement pathway. However, during this preparation of Fc-maleimide, there is apparently some SS-formation between non-homologous SH, so that not all hinges emerge with a reconstituted inter-gamma SS. To reduce this error we have modified the preparative procedure after investigating an initial partial reduction of the hinge, and reviewing the conditions for stochastic alkylation. During partial reduction by dithiothreitol, the two hinge SS were cleaved apparently randomly: there was no evidence for one bond being more susceptible to reduction than the other, and little indication that the reduction of one bond enhanced the susceptibility of the other. By limiting reduction to an average of one SS per molecule, and alkylation to 0.8 SH per molecule, a final Fc-maleimide product is obtained in which most of the molecules have passed through the entire preparation with one of their hinge SS, and by inference much of the hinge conformation, remaining intact.


Asunto(s)
Cadenas gamma de Inmunoglobulina/química , Maleimidas/química , Compuestos de Sulfhidrilo/química , Humanos , Ligandos
9.
Pediatrics ; 95(5): 646-56, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7536915

RESUMEN

OBJECTIVE: To determine the outcomes of bacterial meningitis in school-age survivors. DESIGN: Prospective cohort study. SETTING: Teaching pediatric hospital. CHILDREN: During 1983 through 1986, 158 meningitis survivors, ages 3 months to 14 years, treated at a single center were enrolled. Between 1991 and 1993, 130 children, 82% of the original cohort, were evaluated at a mean age of 8.4 years and a mean of 6.7 years after their meningitis. OUTCOME MEASURES: Blinded neurologic, neuropsychologic, audiologic, behavior, and socio-demographic assessments were compared with those from grade- and sex-matched control children. Multivariate analyses adjusted for age at testing and socio-demographic variables. RESULTS: There was a systematic increase in risk of abnormality or poorer functioning for children with meningitis, compared with control children, across all categories tested, which was significant for fine motor function, Intelligence quotient (IQ) scores, and tests of school behavior, neuropsychologic function, and auditory figure-ground differentiation. Eleven children who had experienced meningitis (8.5%) had major deficits (IQ < 70, seizures, hydrocephalus, spasticity, blindness, or severe to profound hearing loss); a further 24 (18.5%) cases and 14 (10.8%) control children had minor deficits (IQ 70 to 80, inability to read, mild to moderate hearing loss, abnormalities in speech discrimination, or school behavior problems). Overall, children who had meningitis were at greater risk (26.9%) for disability. Children with acute neurologic complications had more adverse outcomes than those with uncomplicated meningitis and control children (39% vs 18% vs 11%, respectively). CONCLUSIONS: One in four school-age meningitis survivors has either serious and disabling sequelae or a functionally important behavior disorder, neuropsychologic or auditory dysfunction adversely affecting academic performance. As a group, survivors function less well than their classroom peers, and risk is greatest for, but not confined to, those who had acute neurologic complications. All survivors require careful follow-up, at least until school age.


Asunto(s)
Trastornos de la Conducta Infantil/etiología , Discapacidades del Desarrollo/etiología , Meningitis Bacterianas/complicaciones , Enfermedades del Sistema Nervioso/etiología , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Estudios de Seguimiento , Trastornos de la Audición/etiología , Humanos , Lactante , Inteligencia , Masculino , Pruebas Neuropsicológicas , Factores de Riesgo , Sobrevivientes
10.
Dis Markers ; 5(1): 19-29, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3502978

RESUMEN

The relative concentrations of pCG14 RNA (a myelocyte-specific mRNA), pAM6 RNA (a monocyte-lineage specific marker), and c-myc RNA (present at higher concentrations in more primitive cells) were measured in the RNAs from peripheral blood leucocytes from leukaemic samples and normal individuals. The potential of differences in the relative abundances of these three RNAs in a series of 34 leukaemias was assessed as a means of distinguishing among the myeloid leukaemias. The chronic phase CGL samples were clustered with a high pCG14 RNA, a medium to low c-myc RNA abundance, and a variable pAM6 RNA level. The ANLL samples could be distinguished from the chronic phase CGL by virtue of different relative abundances of these RNAs: low pCG14, medium to high c-myc and a variable pAM6. The acute phase CGL samples showed a variety of relative RNA abundances with some samples sited within the ANLL region. Using samples obtained during the progression of CGL we have shown a shift in the relative abundances of these RNAs from the CGL region towards the ANLL region, and have suggested that the use of these parameters may allow the progression to acute phase to be monitored and, possibly, predicted.


Asunto(s)
Leucemia Mieloide/genética , Hibridación de Ácido Nucleico , Sondas ARN , ARN Mensajero , ARN Neoplásico , Humanos , Leucemia Mieloide/clasificación , Leucocitos/análisis , Oncogenes
11.
Ann N Y Acad Sci ; 511: 308-17, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3439716

RESUMEN

Recombinant plasmid cDNA libraries representing the polyadenylated RNAs in the myeloid cell lines KG1 and ML1 have been constructed. The screening protocol has identified several clones which contain sequences homologous to RNAs expressed at high abundance in one or more of the myeloid cell lines KG1, ML1 and HL60. The relative abundances of RNAs homologous to three recombinants, pML15, pKG21 and pKGA/F5 were measured by an RNA dot hybridisation method in total RNAs isolated from peripheral blood leukocytes from leukaemic patients and normal individuals. High levels of these RNAs were observed mainly in ANLL and acute phase CML samples. The data suggest that these probes have the potential to sub-divide the ANLLs and to extend a molecular classification of the myeloid leukaemias.


Asunto(s)
ADN Recombinante/aislamiento & purificación , ADN/aislamiento & purificación , Células Madre Hematopoyéticas/análisis , Leucemia/patología , Hibridación de Ácido Nucleico , ARN Mensajero/análisis , ARN Neoplásico/análisis , Enfermedad Aguda , Diferenciación Celular , Células Madre Hematopoyéticas/patología , Humanos , Leucemia/clasificación , Leucemia/genética , ARN Mensajero/genética , ARN Neoplásico/genética , Células Tumorales Cultivadas/análisis
12.
Recent Results Cancer Res ; 159: 104-12, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11785834

RESUMEN

One approach to improving the results of antibody treatment of posttransplant and other lymphomas is to alter the geometry of the antibody molecule so as to enhance its cytotoxicity. When antibody alights on a cell, cytotoxicity can be exerted by initiation of apoptotic signals at the cell surface, and by recruitment of effectors to specific sites on the antibody Fc region. Other routes to cytotoxicity have been described but their generality is debatable. The effectors consist of complement, and a series of potentially cytotoxic cells (macrophages, NK cells, neutrophils and others) bearing Fc-receptors (FcR). Recent evidence suggests that the FcR-bearing cells are the more important in dealing with antibody-coated autologous cells, including tumor cells. If the antibody happens to be of the host IgG class then its Fc region (Fcgamma) will contain a site for attachment of a non-cytotoxic FcR known as FcRB (the Brambell receptor): it is this receptor, present on endothelial cells, which recycles the molecule intact if it happens to be endocytosed and thus prolongs its metabolic life. Replacement of the mouse Fcgamma by human Fcgamma is expected to have three beneficial effects: better recruitment of human effector cells, better persistence of the antibody in extracellular fluid, and removal of a major source of immunogenic epitopes. Chemical manipulations of Fab'gamma and Fcgamma modules, linking them in different geometries via their hinge regions, offers constructs with further enhancements of cytotoxicity. These include Fab2Fc2, in which the presence of dual Fc regions enhances recruitment of both complement and cellular effectors; and bispecific antibody of the same modular formula in which one of the Fab arms is specific for tumor while the other is specific for, and recruits powerfully, a cellular effector.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Inmunoterapia , Linfoma/terapia , Animales , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Citotoxicidad Inmunológica , Humanos , Ratones , Ingeniería de Proteínas
13.
Dev Neuropsychol ; 20(1): 385-406, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11827095

RESUMEN

Although there have been significant theoretical advances in the field of child neuropsychology, developmental features of adolescence have received less attention. Progress in clinical practice is restricted due to a lack of well-standardized, developmentally appropriate assessment techniques. This article addresses these issues in relation to executive skills. These abilities are targeted for 2 reasons: first, because they are often considered to be mature during late childhood and adolescence, despite limited investigation in this age range; and second, because of their central importance to efficient day-to-day functioning. Using a normative sample of 138 children, aged 11.0 to 17.11 years, this article plots the development of executive skills through late childhood and early adolescence and interprets progress in these skills with reference to current neurological and cognitive theory.


Asunto(s)
Cognición/fisiología , Escalas de Wechsler , Adolescente , Australia , Niño , Femenino , Humanos , Masculino
14.
Mutat Res ; 197(2): 303-12, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3277044

RESUMEN

In this study, we expanded the use of the genus Tradescantia to investigate the plant activation of promutagens and further refine the methodology of the plant cell/microbe coincubation assay. Liquid suspension cell cultures of Tradescantia clone 03 and Tradescantia clone 4430 were used to activate the promutagen m-phenylenediamine into a mutagenic compound which was detected by Salmonella typhimurium strain TA98 in the plant cell/microbe coincubation assay. Optimum treatment parameters were established for both plant cell lines. Optimum was defined as the lowest concentration or shortest time period that provided consistently positive results and high rates of revertants. Preliminary experiments with both cell lines defined 2.5 mumoles m-phenylenediamine per plate as the optimum concentration to be used in the determination of the optimal coincubation period and the optimal concentration of plant cells. These experiments also determined the optimal physiological stage at which both clones should be used in the coincubation assay. Differences were found in the optimal of coincubation (1h for clone 03, 2 h for clone 4430) and growth stage (mid-log for clone 03, mid- to late-log for clone 4430). Similar activation responses were seen for both clones when the concentration of plant cells (mg/ml) was varied. Under optimized conditions, clone 03 cells demonstrated an approximately 10% higher activation response than clone 4430.


Asunto(s)
Fenilendiaminas/metabolismo , Plantas/metabolismo , Biotransformación , Células Cultivadas , Células Clonales/metabolismo , Pruebas de Mutagenicidad , Mutágenos/biosíntesis , Mutágenos/farmacología , Fenilendiaminas/farmacología , Salmonella typhimurium/efectos de los fármacos
15.
Mutat Res ; 138(2-3): 157-67, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6392874

RESUMEN

The Tradescantia-Micronucleus (Trad-MCN) test is a simple short-term bioassay for various gaseous and liquid forms of chemical agents, and physical agents such as radiation. 140 agents, directly or indirectly related to human health, were screened for their mutagenicity. Plant cuttings of young inflorescences, in which the pollen mother cells undergo various stages of meiosis, were maintained in nutrient solution for experimentation. Treatments were made either by absorption of the soluble agents through the stem, by diffusion of gaseous agents through the leaves and buds, by exposure to internal/external radiation or by in situ exposure to air pollutants. Micronuclei formed from damaged chromosomes served as the indicators of mutagenicity. Results of 140 agents tested are listed in 9 different categories. (1) Carcinogens/mutagens, (2) common beverages, (3) common chemicals, (4) drugs, (5) pesticides, (6) common household chemicals, (7) radiation and radioisotopes, (8) in situ monitoring, (9) complex environmental mixtures. Out of 140 agents tested, 52 showed positive, 20 showed borderline positive responses and 5 showed strong toxicity. Test results of 41 agents in the present study showed 67% congruity with Ames test results found in the literature.


Asunto(s)
Mutágenos/farmacología , Mutación , Plantas/efectos de los fármacos , Bebidas , Carcinógenos/farmacología , Núcleo Celular/efectos de los fármacos , Núcleo Celular/efectos de la radiación , Humanos , Pruebas de Mutagenicidad/métodos , Plaguicidas/farmacología , Plantas/efectos de la radiación , Salmonella typhimurium/efectos de los fármacos
16.
Child Neuropsychol ; 6(2): 87-100, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16210206

RESUMEN

Bacterial meningitis is a life threatening infection of the central nervous system. This illness is most prevalent early in life when the healthy child is rapidly acquiring language. This study investigated whether children with a history of bacterial meningitis were at risk for language difficulties post illness. Thirty post-meningitic children, aged between 9 years 0 months and 11 years 0 months, participated in this study. Each subject was administered a measure of non-verbal cognitive ability and a range of language tasks. These children performed poorly on applied language tasks, which tap skills used in effective discourse. These deficits occurred despite age appropriate performances on measures of linguistic/grammatical knowledge. These findings clearly illustrate that bacterial meningitis has implications for ongoing language development, which emphasises the importance of long term follow up. In developmental terms, this discrepancy between verbal knowledge and problem solving represents a dissociation between language skills which develop early in life and those which emerge later. This pattern of results suggests that bacterial meningitis may result in a delay in language development. A young age at illness was identified as an additional risk factor for adverse outcome. This study highlights the need to inform parents/guardians that post-meningitic children are at risk for experiencing language difficulties throughout childhood.


Asunto(s)
Trastornos del Desarrollo del Lenguaje/etiología , Meningitis Bacterianas/complicaciones , Daño Encefálico Crónico/diagnóstico , Daño Encefálico Crónico/etiología , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Inteligencia , Trastornos del Desarrollo del Lenguaje/diagnóstico , Pruebas del Lenguaje , Masculino , Riesgo
17.
Neurology ; 76(8): 719-26, 2011 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-21339499

RESUMEN

OBJECTIVES: Fetal exposure to some antiepileptic drugs (AEDs) carries increased risk of major birth defects, and may be associated with reduced intellectual abilities. The impact on language remains unclear. This study aimed to investigate the impact of fetal AED exposure on language skills. METHODS: Women with epilepsy and their children were recruited to this observational study through the Australian Pregnancy Register for Women with Epilepsy and Allied Disorders. Language skills of 102 AED-exposed children were assessed using the Clinical Evaluation of Language Fundamentals, fourth edition (CELF-4). Assessments were conducted blind to drug. Maternal epilepsy, pregnancy, and medical histories were obtained from prospectively collected records. RESULTS: Mean CELF-4 Core Language scores of children exposed to sodium valproate in monotherapy (mean 91.5, SD 17.5) or polytherapy (mean 73.4, SD = 22.3) were significantly below the standardized test mean of 100 (p < 0.05). Mean language scores of children exposed to carbamazepine or lamotrigine monotherapy, or polytherapy without sodium valproate, were not significantly different from normal. First-trimester sodium valproate dose was negatively correlated with language scores, and significantly predicted language scores after controlling for other group differences. CONCLUSIONS: Fetal exposure to sodium valproate increases the risk of language impairment. This should be taken into account when making treatment decisions for women with epilepsy of childbearing age.


Asunto(s)
Anticonvulsivantes/efectos adversos , Trastornos del Desarrollo del Lenguaje/etiología , Lenguaje , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Análisis de Varianza , Distribución de Chi-Cuadrado , Niño , Relación Dosis-Respuesta a Droga , Epilepsia/tratamiento farmacológico , Femenino , Humanos , Trastornos del Desarrollo del Lenguaje/diagnóstico , Masculino , Observación , Valor Predictivo de las Pruebas , Embarazo
18.
Int J Dev Neurosci ; 29(2): 137-43, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21147212

RESUMEN

Traumatic brain injury (TBI) in children results in damage to the developing brain, particularly in severely injured individuals. Little is known, however, of the long-term structural aspects of the brain following childhood TBI. This study investigated the integrity of the brain 10 years post-TBI using magnetic resonance imaging volumetrics in a sample of 49 participants with mild, moderate and severe TBI, evaluated against a normative sample of 20 individuals from a pediatric database with comparable age and gender distribution. Structural integrity was investigated in gray and white matter, and by manually segmenting two regions of interest (hippocampus, amygdala), potentially vulnerable to the effects of childhood TBI. The results indicate that more severe injuries caused a reduction in gray and white brain matter, while all TBI severity levels resulted in increased volumes of cerebrospinal fluid and smaller hippocampal volumes. In addition, enlarged amygdala volumes were detected in severely injured patients compared to their mild and moderate counterparts, suggesting that childhood TBI may disrupt the development of certain brain regions through diffuse pathological changes. The findings highlight the lasting impact of childhood TBI on the brain and the importance of monitoring brain structure in the long-term after early injury.


Asunto(s)
Amígdala del Cerebelo/anatomía & histología , Amígdala del Cerebelo/patología , Lesiones Encefálicas/patología , Hipocampo/anatomía & histología , Hipocampo/patología , Adolescente , Amígdala del Cerebelo/crecimiento & desarrollo , Atrofia/patología , Mapeo Encefálico/métodos , Niño , Preescolar , Hipocampo/crecimiento & desarrollo , Humanos , Lactante , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos
20.
J Neurol Neurosurg Psychiatry ; 76(3): 401-8, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15716536

RESUMEN

OBJECTIVE: To examine the contributions of injury severity, physical and cognitive disability, child and family function to outcome 30 months after traumatic brain injury (TBI) in children. DESIGN: A prospective, longitudinal, between group design, comparing function before and after injury across three levels of injury severity. SUBJECTS: One hundred and fifty children, 3.0-12.11 years old, admitted to hospital with a diagnosis of TBI. The sample was divided according to injury severity: mild (n = 42), moderate (n = 70), severe (n = 38). Children with a history of neurological, developmental, and psychiatric disorders were excluded from participation. MAIN OUTCOME MEASURES: Post injury physical function, cognitive ability (incorporating intellect, memory, and attention), behavioural and family functioning, and level of family burden. RESULTS: A dose-response relation was identified for injury severity and physical and cognitive outcome, with significant recovery documented from acute to six months after TBI. Behavioural functioning was not related to injury severity, and where problems were identified, little recovery was noted over time. Family functioning remained unchanged from preinjury to post injury assessments. The level of family burden was high at both six and 30 months after injury, and was predicted by injury severity, functional impairment, and post injury child behavioural disturbance. CONCLUSIONS: These results suggest ongoing problems for the child and significant family burden 30 months after TBI. The nature and severity of the physical and cognitive problems are closely related to injury severity, with child and family function predicted by psychosocial and premorbid factors.


Asunto(s)
Lesiones Encefálicas/rehabilitación , Trastornos del Conocimiento/etiología , Costo de Enfermedad , Salud de la Familia , Adaptación Psicológica , Adulto , Niño , Preescolar , Femenino , Estado de Salud , Humanos , Masculino , Pronóstico , Estudios Prospectivos , Índice de Severidad de la Enfermedad
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