Comparison Among Children with Children with Autism Spectrum Disorder, Nonverbal Learning Disorder and Typically Developing Children on Measures of Executive Functioning

It has been suggested that children with nonverbal learning disabilities (NLD) or Asperger’s Syndrome (AS) may show difficulties with executive functioning. There were 3 groups in this study who completed a neuropsychological battery of visual-spatial, executive functioning, and reasoning tasks; AS (n = 37), NLD (n = 31), and controls (n = 40). Results indicated that children in both clinical groups scored within average limits on measures of spatial reasoning and verbal ability. Fluid reasoning was also found to be within average ranges for all groups. The AS group experienced significant problems with cognitive flexibility compared to the other two groups. In contrast the NLD group showed fewer difficulties with cognitive flexibility but more problems with visual sequencing. These findings suggest that performance on executive function measures for children with AS or NLD is remarkably similar with subtle differences present.     

Addressing Environmental Health Concerns near Trecatti Landfill Site,United Kingdom

Residents near the Trecatti landfill site located in South Wales, United Kingdom, expressed concern about odors and health effects they attributed to site emissions. The authors compared routinely collected, population-based, health data from potentially exposed electoral wards (i.e., United Kingdom electoral tracts) with data from both wards nearby, matched for socioeconomic deprivation scores, and with wards where residents were likely to attend the same hospital. Mortality rates were higher for all causes and neoplastic diseases (but not respiratory disease) in the exposed wards, but there was no change in rates after the site opened. Hospital data revealed a transient increase in admissions for asthma during the 3 yr that preceded the peak in odor complaints. The birth prevalence of congenital malformations was raised in the exposed wards, but the authors could not exclude a possible artifact resulting from differences in reporting practices between hospitals. The absence of environmental monitoring in the community during the period of public concern was a significant weakness of this study.     

Laser‐mediated cell ablation during post‐implantation mouse development

BACKGROUND: Laser‐mediated cell ablation is a powerful tool that has been used to understand cell fate in a variety of externally developing organisms but has not been used during mammalian post‐implantation development. RESULTS: We describe a method pairing laser ablation with murine embryo culture and establish parameters that can be used to precisely ablate cells in the selected field with minimal disruption to adjacent cells or the underlying cell matrix. Ablation of a large domain of endoderm, followed by ～1 day of culture results in a phenotypically normal embryo and gut tube, indicating that laser ablation is compatible with normal development. We next focused on one of the three precursor populations that have been shown to produce the liver bud. Ablations of a single progenitor domain result in a unilateral delay in the liver bud while the contralateral side is unaffected. CONCLUSIONS: We demonstrate that laser ablation is a specific and useful technique for studying cell fate in the mouse embryo. This method represents a powerful advance in developmental studies in the mouse and can be used to provide information on the specification of organs, differentiation, cell migration, and vital tissue interactions during development. Developmental Dynamics, 242:1202–1209, 2013. © 2013 Wiley Periodicals, Inc.     

Platelet‐rich plasma enhances the integration of bioengineered cartilage with native tissue in an in vitro model

Current therapies for cartilage repair can be limited by an inability of the repair tissue to integrate with host tissue. Thus, there is interest in developing approaches to enhance integration. We have previously shown that platelet‐rich plasma (PRP) improves cartilage tissue formation. This raised the question as to whether PRP could promote cartilage integration . Chondrocytes were isolated from cartilage harvested from bovine joints, seeded on a porous bone substitute and grown in vitro to form an osteochondral‐like implant. After 7 days, the biphasic construct was soaked in PRP for 30 min before implantation into the core of a donut‐shaped biphasic explant of native cartilage and bone. Controls were not soaked in PRP. The implant–explant construct was cultured for 2–4 weeks. PRP‐soaked bioengineered implants integrated with host tissue in 73% of samples, whereas controls only integrated in 19% of samples. The integration strength, as determined by a push‐out test, was significantly increased in the PRP‐soaked implant group (219 ± 35.4 kPa) compared with controls (72.0 ± 28.5 kPa). This correlated with an increase in glycosaminoglycan and collagen accumulation in the region of integration in the PRP‐treated implant group, compared with untreated controls. Immunohistochemical studies revealed that the integration zone contained collagen type II and aggrecan. The cells at the zone of integration in the PRP‐soaked group had a 3.5‐fold increase in matrix metalloproteinase‐13 gene expression compared with controls. These results suggest that PRP‐soaked bioengineered cartilage implants may be a better approach for cartilage repair due to enhanced integration.     

Housing Status and HIV Risk Behaviors Among Transgender Women in Los Angeles

Due to social stigma, lack of social support, and minimal legal employment opportunities, transgender women (transwomen) face elevated rates of unstable housing. This study examined the association between housing status and HIV risk behaviors among 517 transwomen encountered through street outreach. Seven variables (including sociodemographics, HIV status, housing status, and sexual partner type) were used to estimate partial associations during multivariable analyses; housing status was coded trichotomously (housed, marginally housed, and homeless) for these analyses. Results demonstrated that homeless and marginally housed transwomen engaged in significantly higher rates of illicit drug use than housed transwomen; however, marginally housed and housed transwomen engaged in significantly higher rates of illegal hormone injections than homeless transwomen. Rates of sex work were high in the sample as a whole, though sex with an exchange partner was most common among the marginally housed transwomen. Multivariate logistic regression revealed that unstable housing moderated the association between HIV status and engagement in unprotected serodiscordant anal intercourse. The marginally housed transwomen exhibited the greatest risk profile for HIV acquisition or transmission.