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Abstract: 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. [Copyright &y& Elsevier]

Experiments were carried out to determine the influence of antigen density on anti-complementary modulation, defined here as the conferring by anti-immunoglobulin (Ig) of resistance to lysis of guinea pig L2k leukaemic lymphocytes through anti-lg plus syngeneic complement (C). Populations of leukaemic cells varied widely in their quantitative expression of surface membrane Ig as judged by the binding to cells of 125I-labelled Fab' fragments from anti-Ig and a good correlation between the hulk antigen density and the percentage of cells lysed by anti-lg plus C was obtained (P=0.02). In the presence of 10 mM sodium azide, which has been shown to diminish the modulation occuring during simultaneous incubations with anti-Ig and C, this correlation was even stronger (P< 0.001). No zone could be defined in which the level of surface Ig expression was sufficient to serve complement Iysis but too low for modulation. Furthermore, both the degrees and rates of modulation occurring on incubation with antibody at 37°C, either before C addition or in the presence of lytic C, were similar for populations of high, low, or intermediate antigen density. Separation of cells by their site or density failed to yield populations differing in either their susceptibility to humoral killing through anti-Ig or their modulating capacity. IgG and IgM antibodies to the L2C cell surface Ig evoked similar levels of killing with syngeneic C. and when compared for their ability to promote anti-complementary modulation, no difference was revealed in either the rate or degree of modulation occurring during incubations at 37°C with the two isotypes. The findings are discussed with particular reference to observations on the modulation of mouse thymus leukaemia (TL) antigens. [ABSTRACT FROM AUTHOR]

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. Image 1 • Predation on sentinel preys is greater in cotton fields treated with selective insecticides. • Seasonal abundance of predatory insects is about two-fold greater in cotton areas treated with selective insecticides. • Survival of key predators is high when exposed to pymetrozine, chlorantraniliprole, pyriproxyfen, and cyantraniliprole. • Impact on predator survival is shorter with malathion and dimethoate in comparison to lambda-cyhalothrin and thiamethoxam. [ABSTRACT FROM AUTHOR]

Examines the outcome of bacterial meningitis in children. Presence of neurologic abnormalities; Factor of an increasing risk of morbidity; Defects in the executive function and academic achievement domains.