Intrarectal transmission, systemic infection, and CD4+ T cell depletion in humanized mice infected with HIV-1

Intrarectal infection between men who have sex with men represents a predominant form of human immunodeficiency virus (HIV) transmission in developed countries. Currently there are no adequate small animal models that recapitulate intrarectal HIV transmission. Here we demonstrate that human lymphocytes generated in situ from hematopoietic stem cells reconstitute the gastrointestinal tract of humanized mice with human CD4+ T cells rendering them susceptible to intrarectal HIV transmission. HIV infection after a single intrarectal inoculation results in systemic infection with depletion of CD4+ T cells in gut-associated lymphoid tissue and other pathologic sequela that closely mimics those observed in HIV infected humans. This novel model provides the basis for the development and evaluation of novel approaches aimed at immune reconstitution of human gut-associated lymphoid tissue and for the development, testing, and implementation of microbicides to prevent intrarectal HIV-1 transmission

Personality profiles of cultures: aggregate personality traits

Personality profiles of cultures can be operationalized as the mean trait levels of culture members. College students from 51 cultures rated an individual from their country whom they knew well (N = 12, 156). Aggregate scores on Revised NEO Personality Inventory scales generalized across age and gender groups, approximated the individual-level Five-Factor Model, and correlated with aggregate self-report personality scores and other culture-level variables. Results were not attributable to national differences in economic development or to acquiescence. Geographical differences in scale variances and mean levels were replicated, with Europeans and Americans generally scoring higher in Extraversion than Asians and Africans. Findings support the rough scalar equivalence of NEO-PI-R factors and facets across cultures, and suggest that aggregate personality profiles provide insight into cultural differences

Simian Immunodeficiency Virus–Induced Intestinal Cell Apoptosis Is the Underlying Mechanism of the Regenerative Enteropathy of Early Infection

The enteropathic manifestations of the human immunodeficiency virus (HIV) and the simian immunodeficiency virus (SIV) in late infection are usually due to infection by other microbes, but in early infection the viruses themselves cause an enteropathy by heretofore undetermined mechanisms. Here we report that SIV induces massive apoptosis of intestinal epithelial cells lining the small and large bowel, thus identifying apoptosis as the driving force behind the regenerative pathology of early infection. We found that apoptosis of gut epithelium paralleled the previously documented apoptosis and massive depletion of CD4 T cells in gut lamina propria, triggered by established mechanisms of gut epithelial cell apoptosis and, at peak, possibly by virus interactions with GPR15/Bob, an intestinal epithelial cell–associated alternative coreceptor for SIV and HIV-1. Apoptosis in early SIV infection is thus the common theme of the pathological processes that quickly afflict the innate as well as adaptive arms of the gut immune system

Visual, Auditory, and Cross Modal Sensory Processing in Adults with Autism:An EEG Power and BOLD fMRI Investigation

Electroencephalography (EEG) and Blood Oxygen Level Dependent Functional Magnetic Resonance Imagining (BOLD fMRI) assessed the neurocorrelates of sensory processing of visual and auditory stimuli in 11 adults with autism (ASD) and 10 neurotypical (NT) controls between the ages of 20-28. We hypothesized that ASD performance on combined audiovisual trials would be less accurate with observable decreased EEG power across frontal, temporal, and occipital channels and decreased BOLD fMRI activity in these same regions; reflecting deficits in key sensory processing areas. Analysis focused on EEG power, BOLD fMRI, and accuracy. Lower EEG beta power and lower left auditory cortex fMRI activity were seen in ASD compared to NT when they were presented with auditory stimuli as demonstrated by contrasting the activity from the second presentation of an auditory stimulus in an all auditory block versus the second presentation of a visual stimulus in an all visual block (AA2­VV2). We conclude that in ASD, combined audiovisual processing is more similar than unimodal processing to NTs

Developing pronunciation skills at the introductory level: motivating students through interpersonal audio discussions

This study investigated students' motivation to develop pronunciation skills while participating in shared conversations called interpersonal audio discussions because research has suggested that learners desire pronunciation instruction in hopes of achieving native-like pronunciation (Gilakjani & Ahmadi, 2011; Harlow & Muyskens, 1994; Drewelow & Theobald, 2007) and that social environments are useful in developing proficiency in a second language (Atkinson, 2002; Aubry, 2009; Ducate & Lomicka, 2009; Firth & Wagner, 1997; Kramsch & Whiteside, 2007; Lee, 2014; Lord, 2008; Pica, 1994b; Smith, Alvarez-Torres & Zhao, 2003; Warschauer, 1996). Due to the plethora of online learning communities, there is also a need for research-based findings that evaluate emerging pedagogical tools for pronunciation development. Participants in the present study were enrolled in a second-semester French course where they focused on pronunciation skills in a web-based software called VoiceThread. Through two questionnaires, journal entries, and assessment activities, students continuously self-reported about the effects of participation on perceptions of pronunciation and its development. Data was analyzed through a mixed methods approach. Results indicated that students had more positive opinions of performance on pronunciation-related tasks as well as higher L2 self-confidence associated with pronunciation after participation. Furthermore, findings detailed how increased interactivity in VoiceThread influenced students' motivation in pronunciation. The study's conclusions maintain that participation in VoiceThread raises students' awareness of their performance in pronunciation thereby creating a feedback-supported environment conducive not only to pronunciation development but also to self-motivation regarding the skill. (Published By University of Alabama Libraries

Kinetics of response in lymphoid tissues to antiretroviral therapy of HIV-1 infection

In lymphoid tissue, where human immunodeficiency virus-type 1 (HIV-1) is produced and stored, three-drug treatment with viral protease and reverse transcriptase inhibitors markedly reduced viral burden. This was shown by in situ hybridization and computerized quantitative analysis of serial tonsil biopsies from previously untreated adults. The frequency of productive mononuclear cells (MNCs) initially diminished with a half-life of about 1 day. Surprisingly, the amount of HIV-1 RNA in virus trapped on follicular dendritic cells (FDCs) decreased almost as quickly. After 24 weeks, MNCs with very few copies of HIV-1 RNA per cell were still detectable, as was proviral DNA; however, the amount of FDC-associated virus decreased by ≤3.4 log units. Thus, 6 months of potent therapy controlled active replication and cleared >99.9 percent of virus from the secondary lymphoid tissue reservoir