532 research outputs found
Relationship between hippocampal structure and memory function in elderly humans
With progressing age, the ability to recollect personal events declines, whereas familiarity-based memory remains relatively intact. It has been hypothesized that age-related hippocampal atrophy may contribute to this pattern because of its critical role for recollection in younger humans and after acute injury. Here, we show that hippocampal volume loss in healthy older persons correlates with gray matter loss (estimated with voxel-based morphometry) of the entire limbic system and shows no correlation with an electrophysiological (event-related potential [ERP]) index of recollection. Instead, it covaries with more substantial and less specific electrophysiological changes of stimulus processing. Age-related changes in another complementary structural measure, hippocampal diffusion, on the other hand, seemed to be more regionally selective and showed the expected correlation with the ERP index of recollection. Thus, hippocampal atrophy in older persons accompanies limbic atrophy, and its functional impact on memory is more fundamental than merely affecting recollection
Brief Report: Does Gender Matter in Intervention for ASD? Examining the Impact of the PEERSÂź Social Skills Intervention on Social Behavior Among Females with ASD
A paucity of research has been conducted to examine the effect of social skills intervention on females with ASD. Females with ASD may have more difficulty developing meaningful friendships than males, as the social climate can be more complex (Archer, Coyne, Personality and Social Psychology Review 9(3):212â230, 2005). This study examined whether treatment response among females differed from males. One hundred and seventy-seven adolescents and young adults with ASD (Nâ=â177) participated in this study. When analyzed by group, no significant differences by gender emerged: PEERSÂź knowledge (TASSK/TYASSK, pâ=â.494), direct interactions (QSQ, pâ=â.762), or social responsiveness (SRS, pâ=â.689; SSIS-RS, pâ=â.482). Thus, females and males with ASD respond similarly to the PEERSÂź intervention
Changes in Depressive Symptoms Among Adolescents with ASD Completing the PEERSÂź Social Skills Intervention
Depression is a common concern among people with autism spectrum disorder (ASD) and is often associated with social skills and relationship challenges. The present data, from a randomized controlled trial, examined the effect of PEERSÂź on self-reported depressive symptoms via the Childrenâs Depression Inventory (CDI) among 49 adolescents with ASD. Findings revealed that many CDI subscale scores declined (pâsâ\u3câ0.05) and were related to direct social contact on the Quality of Socialization Questionnaire at posttest (pâsâ\u3câ0.05). Exploratory analyses uncovered that suicidality was less evident following PEERSÂź. Findings support the notion that social functioning and depression may be intimately intertwined in ASD; therefore, bolstering social skills in ASD may positively influence other domains of functioning, including mental health
Examining the Links Between Challenging Behaviors in Youth with ASD and Parental Stress, Mental Health, and Involvement: Applying an Adaptation of the Family Stress Model to Families of Youth with ASD
Raising a child with autism spectrum disorder (ASD) poses unique challenges that may impact parentsâ mental health and parenting experiences. The current study analyzed self-report data from 77 parents of youth with ASD. A serial multiple mediation model revealed that parenting stress (SIPA) and parental mental health (BAI and BDI-II) appears to be impacted by challenging adolescent behaviors (SSIS-PBs) and, in turn, affect parental involvement (PRQ), controlling for social skills (SSIS-SSs). Further, the study explored the malleability of parentsâ mental health over the course of a social skills intervention, and provides modest evidence that parent depressive symptoms decline across intervention. This study illustrates the importance of considering the entire family system in research on youth with ASD
Zika Virus-Specific IgY Results Are Therapeutic Following a Lethal Zika Virus Challenge without Inducing Antibody-Dependent Enhancement
The Zika virus (ZIKV) is a newly emerged pathogen in the Western hemisphere. It was declared a global health emergency by the World Health Organization in 2016. There have been 223,477 confirmed cases, including 3720 congenital syndrome cases since 2015. ZIKV infection symptoms range from asymptomatic to GullainâBarrĂ© syndrome and extensive neuropathology in infected fetuses. Passive and active vaccines have been unsuccessful in the protection from or the treatment of flaviviral infections due to antibody-dependent enhancement (ADE). ADE causes an increased viral load due to an increased monocyte opsonization by non-neutralizing, low-avidity antibodies from a previous dengue virus (DENV) infection or from a previous exposure to ZIKV. We have previously demonstrated that polyclonal avian IgY generated against whole-killed DENV-2 ameliorates DENV infection in mice while not inducing ADE. This is likely due to the inability of the Fc portion of IgY to bind to mammalian Fc receptors. We have shown here that ZIKV oligoclonal IgY is able to neutralize the virus in vitro and in IFNARâ/â mice. The concentration of ZIKV-specific IgY yielding 50% neutralization (NT50) was 25 ”g/mL. The exposure of the ZIKV, prior to culture with ZIKV-specific IgY or 4G2 flavivirus-enveloped IgG, demonstrated that the ZIKV-specific IgY does not induce ADE. ZIKV IgY was protective in vivo when administered following a lethal ZIKV challenge in 3-week-old IFNARâ/â mice. We propose polyclonal ZIKV-specific IgY may provide a viable passive immunotherapy for a ZIKV infection without inducing ADE
Social Difficulties in Youth with Autism With and Without Anxiety and ADHD Symptoms
Social difficulties inherent to autism spectrum disorder are often linked with coâoccurring symptoms of anxiety and attention deficit hyperactivity disorder (ADHD). The present study sought to examine the relation between such coâoccurring symptoms and social challenges. Parents of adolescents with autism (N = 113) reported upon social challenges via the social responsiveness scale (SRS) and anxiety and ADHD symptomatology via the Child Behavior Checklist. Results revealed differences in SRS scores across coâoccurring symptom subgroups (Anxiety, ADHD, Both, Neither)ânamely, adolescents with autism and anxiety as well as those with autism, anxiety, and ADHD showed greater scores on the SRS than the other groups. Implications for research and clinical practice are discussed and recommendations are offered. Lay Summary
Anxiety and attention deficit hyperactivity disorder (ADHD) symptoms are related to greater social challenges for adolescents with autism spectrum disorder. The present study found that autism with anxiety and autism with anxiety and ADHD, was related to greater social difficulties than autism alone. Findings provide further support for the intertwined nature of anxiety and ADHD symptoms in autism. What this may mean for research and clinical practice is considered and recommendations are suggested
Social Difficulties in Youth with Autism With and Without Anxiety and ADHD Symptoms
Social difficulties inherent to autism spectrum disorder are often linked with coâoccurring symptoms of anxiety and attention deficit hyperactivity disorder (ADHD). The present study sought to examine the relation between such coâoccurring symptoms and social challenges. Parents of adolescents with autism (N = 113) reported upon social challenges via the social responsiveness scale (SRS) and anxiety and ADHD symptomatology via the Child Behavior Checklist. Results revealed differences in SRS scores across coâoccurring symptom subgroups (Anxiety, ADHD, Both, Neither)ânamely, adolescents with autism and anxiety as well as those with autism, anxiety, and ADHD showed greater scores on the SRS than the other groups. Implications for research and clinical practice are discussed and recommendations are offered. Lay Summary
Anxiety and attention deficit hyperactivity disorder (ADHD) symptoms are related to greater social challenges for adolescents with autism spectrum disorder. The present study found that autism with anxiety and autism with anxiety and ADHD, was related to greater social difficulties than autism alone. Findings provide further support for the intertwined nature of anxiety and ADHD symptoms in autism. What this may mean for research and clinical practice is considered and recommendations are suggested
Dual chaperone role of the c-terminal propeptide in folding and oligomerization of the pore-forming toxin aerolysin
Throughout evolution, one of the most ancient forms of aggression between cells or organisms has been the production of proteins or peptides affecting the permeability of the target cell membrane. This class of virulence factors includes the largest family of bacterial toxins, the pore-forming toxins (PFTs). PFTs are bistable structures that can exist in a soluble and a transmembrane state. It is unclear what drives biosynthetic folding towards the soluble state, a requirement that is essential to protect the PFT-producing cell. Here we have investigated the folding of aerolysin, produced by the human pathogen Aeromonas hydrophila, and more specifically the role of the C-terminal propeptide (CTP). By combining the predictive power of computational techniques with experimental validation using both structural and functional approaches, we show that the CTP prevents aggregation during biosynthetic folding. We identified specific residues that mediate binding of the CTP to the toxin. We show that the CTP is crucial for the control of the aerolysin activity, since it protects individual subunits from aggregation within the bacterium and later controls assembly of the quaternary pore-forming complex at the surface of the target host cell. The CTP is the first example of a C-terminal chain-linked chaperone with dual function
Do not drop: Mechanical shock in vials causes cavitation, protein aggregation and particle formation
Industry experience suggests that g-forces sustained when vials containing protein formulations are accidentally dropped can cause aggregation and particle formation. To study this phenomenon, a shock tower was used to apply controlled g-forces to glass vials containing formulations of two monoclonal antibodies and recombinant human growth hormone (rhGH). High-speed video analysis showed cavitation bubbles forming within 30 ÎŒs and subsequently collapsing in the formulations. As a result of echoing shock waves, bubbles collapsed and reappeared periodically over a millisecond timecourse. Fluid mechanics simulations showed low-pressure regions within the fluid where cavitation would be favored. A hydroxyphenylfluorescein assay determined that cavitation produced hydroxyl radicals. When mechanical shock was applied to vials containing protein formulations, gelatinous particles appeared on the vial walls. Size exclusion chromatographic analysis of the formulations after shock did not detect changes in monomer or soluble aggregate concentrations. However, subvisible particle counts determined by microflow image analysis increased. The mass of protein attached to the vial walls increased with increasing drop height. Both protein in bulk solution and protein that became attached to the vial walls after shock were analyzed by mass spectrometry. rhGH recovered from the vial walls in some samples revealed oxidation of Met and/or Trp residues
- âŠ