CD4+CD25+ TR Cells Suppress Innate Immune Pathology Through Cytokine-dependent Mechanisms

CD4+CD25+ regulatory T (TR) cells can inhibit a variety of autoimmune and inflammatory diseases, but the precise mechanisms by which they suppress immune responses in vivo remain unresolved. Here, we have used Helicobacter hepaticus infection of T cell–reconstituted recombination-activating gene (RAG)−/− mice as a model to study the ability of CD4+CD25+ TR cells to inhibit bacterially triggered intestinal inflammation. H. hepaticus infection elicited both T cell-mediated and T cell–independent intestinal inflammation, both of which were inhibited by adoptively transferred CD4+CD25+ TR cells. T cell–independent pathology was accompanied by activation of the innate immune system that was also inhibited by CD4+CD25+ TR cells. Suppression of innate immune pathology was dependent on T cell–derived interleukin 10 and also on the production of transforming growth factor β. Thus, CD4+CD25+ TR cells do not only suppress adaptive T cell responses, but are also able to control pathology mediated by innate immune mechanisms

Sexually Dimorphic Effects of Prenatal Stress on Cognition, Hormonal Responses, and Central Neurotransmitters

Exposure to stress during gestation results in physiological and behavioral alterations that persist into adulthood. This study examined the effects of prenatal stress on the postnatal expression of sexually differentiated cognitive, hormonal, and neurochemical profiles in male and female rats. Pregnant dams were subjected to restraint stress three times daily for 45 min during d 14-21 of pregnancy. The offspring of control and prenatally stressed dams were tested for anxiety-related and cognitive behaviors, stress and gonadal steroid hormone levels, as well as monoamines and metabolite levels in selected brain regions. Postnatal testosterone levels (measured at 1 and 5 d) did not differ between controls and prenatally stressed animals. In adulthood, the serum corticosterone response to stress was attenuated in prenatally stressed females, eliminating the sex difference normally observed in this parameter. Prenatally stressed females exhibited higher anxiety levels, evidenced by longer open field entry latencies. Prenatal stress had no effect on object recognition memory, but eliminated the advantage normally seen in the male performance of a spatial memory task. Neurochemical profiles of prenatally stressed females were altered toward the masculine phenotype in the prefrontal cortex, amygdala, and hippocampus. Thus, prenatal stress altered subsequent cognitive, endocrine, and neurochemical responses in a sex-specific manner. These data reinforce the view that prenatal stress affects multiple aspects of brain development, interfering with the expression of normal behavioral, neuroendocrine, and neurochemical sex differences. These data have implications for the effects of prenatal stress on the development of sexually dimorphic endocrine and neurological disorders

Simulations of Dust in Interacting Galaxies I: Dust Attenuation

A new Monte-Carlo radiative-transfer code, Sunrise, is used in conjunction with hydrodynamic simulations of major galaxy mergers to calculate the effects of dust in such systems. The simulations are in good agreement with observations of dust absorption in starburst galaxies, and the dust has a profound effect on their appearance. The dust attenuation increases with luminosity such that at peak luminosities ~90% of the bolometric luminosity is absorbed by dust. In general, the detailed appearance of the merging event depends on the stage of the merger and the geometry of the encounter. The fraction of bolometric energy absorbed by the dust, however, is a robust quantity that can be predicted from the intrinsic properties bolometric luminosity, baryonic mass, star-formation rate, and metallicity of the system. This paper presents fitting formulae, valid over a wide range of masses and metallicities, from which the absorbed fraction of luminosity (and consequently also the infrared dust luminosity) can be predicted. The attenuation of the luminosity at specific wavelengths can also be predicted, albeit with a larger scatter due to the variation with viewing angle. These formulae for dust attenuation appear to be valid for both isolated and interacting galaxies, are consistent with earlier studies, and would be suitable for inclusion in theoretical models, e.g. semi-analytic models of galaxy formation.Comment: 12 pages, 10 figures, submitted to Ap

Fabrication of low-cost, large-area prototype Si(Li) detectors for the GAPS experiment

A Si(Li) detector fabrication procedure has been developed with the aim of satisfying the unique requirements of the GAPS (General Antiparticle Spectrometer) experiment. Si(Li) detectors are particularly well-suited to the GAPS detection scheme, in which several planes of detectors act as the target to slow and capture an incoming antiparticle into an exotic atom, as well as the spectrometer and tracker to measure the resulting decay X-rays and annihilation products. These detectors must provide the absorption depth, energy resolution, tracking efficiency, and active area necessary for this technique, all within the significant temperature, power, and cost constraints of an Antarctic long-duration balloon flight. We report here on the fabrication and performance of prototype 2"-diameter, 1-1.25 mm-thick, single-strip Si(Li) detectors that provide the necessary X-ray energy resolution of $\sim$4 keV for a cost per unit area that is far below that of previously-acquired commercial detectors. This fabrication procedure is currently being optimized for the 4"-diameter, 2.5 mm-thick, multi-strip geometry that will be used for the GAPS flight detectors.Comment: Accepted for publication at Nuclear Instrumentation and Methods A, 12 pages, 11 figure

In-situ resonant band engineering of solution-processed semiconductors generates high performance n-type thermoelectric nano-inks.

Thermoelectric devices possess enormous potential to reshape the global energy landscape by converting waste heat into electricity, yet their commercial implementation has been limited by their high cost to output power ratio. No single "champion" thermoelectric material exists due to a broad range of material-dependent thermal and electrical property optimization challenges. While the advent of nanostructuring provided a general design paradigm for reducing material thermal conductivities, there exists no analogous strategy for homogeneous, precise doping of materials. Here, we demonstrate a nanoscale interface-engineering approach that harnesses the large chemically accessible surface areas of nanomaterials to yield massive, finely-controlled, and stable changes in the Seebeck coefficient, switching a poor nonconventional p-type thermoelectric material, tellurium, into a robust n-type material exhibiting stable properties over months of testing. These remodeled, n-type nanowires display extremely high power factors (~500 µW m-1K-2) that are orders of magnitude higher than their bulk p-type counterparts

The Role of Loneliness as a Mediator Between Autism Features and Mental Health Among Autistic Young Adults

Autistic adults commonly experience anxiety and depression. These mental health concerns are often tied to social experiences, such that mental well-being can be supported by social connection and deteriorated by loneliness. The mediating role of social and emotional loneliness (i.e. social isolation and lack of emotional attachment, respectively) between autism features and mental health has yet to be empirically tested among autistic adults. Here, 69 autistic young adults completed self-report questionnaires assessing social contact (Friendship Questionnaire), autism features (Autism Quotient), mental health (Liebowitz Social Anxiety Scale, Social Phobia Inventory, Beck Depression Inventory), and loneliness (Social and Emotional Loneliness Scale for Adults). Positive associations emerged between autism features, social loneliness, family loneliness, social anxiety, and depression. In addition, more social contact was related to less social and family loneliness and less social anxiety but was not related to depression. Mediation analyses indicated significant indirect effects of social contact and autism features on mental health through social loneliness. Indirect effects partially held substituting family loneliness for social loneliness and did not hold using romantic loneliness. In light of these results, the scientific and clinical implications of the role of loneliness for autistic young adults are discussed and recommendations provided. Lay abstract Autistic adults commonly experience mental health concerns including social anxiety and depression, which can have negative effects on their quality of life. It is not completely clear, however, why rates of mental health concerns are so high. Some evidence suggests that social connectedness might play a key role. The goal of this study was to explore links between loneliness, mental health concerns, autism features, and social contact among autistic adults and test whether the links between mental health with autism features and social contact can be explained by loneliness. Researchers in this study collected data using questionnaires completed by 69 autistic young adults. Autistic adults who reported more autism features also reported more social and family loneliness, higher levels of social anxiety and depression, and fewer initiated social contacts. In addition, adults with more social contact initiations were likely to report lower levels of social and family loneliness and social anxiety but not depression. Results showed that the link from social engagement and autism features to social anxiety and depression symptoms could be mostly explained by loneliness. The results of this study expand previous findings by illustrating one factor (loneliness) that might be responsible for the high rates of mental health concerns among adults on the autism spectrum. These findings highlight the importance of studying factors related to mental health concerns among autistic adults and ways to best support social connectedness for the mental well-being of autistic young adults

Who's most at risk of poor body image? Identifying subgroups of adolescent social media users over the course of a year

Types and stability of appearance-related social media use patterns remain under-explored despite established links between social media use and wellbeing. This study aimed to identify subgroups of social media users, and explore whether subgroup membership was stable over time and associated with body image-related outcomes. Adolescents (N = 766; Mage = 12.76, SD = 0.73; 49.40% female) completed four surveys across 1-year, reporting several social media use indices, body dissatisfaction, dietary restraint, and strategies to increase muscle. Latent profile analyses identified two subgroups (moderate and high users), that remained reasonably stable over time. The high subgroup exhibited poorer body image at baseline, though differences seemed to dissipate somewhat over 1-year. Examination of subgroup transition over time showed more rapid increases in poor body image outcomes among social media increasers and more rapid declines for reducers. Prevention programs which aim to reduce high levels of social media use among children, young adolescents, and high-risk individuals (i.e., appearance-focused users) appear warranted

Metabolic and Transcriptional Modules Independently Diversify Plasma Cell Lifespan and Function

Plasma cell survival and the consequent duration of immunity vary widely with infection or vaccination. Using fluorescent glucose analog uptake, we defined multiple developmentally independent mouse plasma cell populations with varying life- spans. Long-lived plasma cells imported more fluo- rescent glucose analog, expressed higher surface levels of the amino acid transporter CD98, and had more autophagosome mass than did short-lived cells. Low amino acid concentrations triggered re- ductions in both antibody secretion and mitochon- drial respiration, especially by short-lived plasma cells. To explain these observations, we found that glutamine was used for both mitochondrial respira- tion and anaplerotic reactions, yielding glutamate and aspartate for antibody synthesis. Endoplasmic reticulum (ER) stress responses, which link meta- bolism to transcriptional outcomes, were similar between long- and short-lived subsets. Accordingly, population and single-cell transcriptional compari- sons across mouse and human plasma cell subsets revealed few consistent and conserved dif- ferences. Thus, plasma cell antibody secretion and lifespan are primarily defined by non-transcriptional metabolic traits