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Pilot randomized trial demonstrating reversal of obesity-related abnormalities in reward system responsivity to food cues with a behavioral intervention
Objectives: Obesity is associated with hyperactivation of the reward system for high-calorie (HC) versus low-calorie (LC) food cues, which encourages unhealthy food selection and overeating. However, the extent to which this hyperactivation can be reversed is uncertain, and to date there has been no demonstration of changes by behavioral intervention. Subjects and methods: We used functional magnetic resonance imaging to measure changes in activation of the striatum for food images at baseline and 6 months in a pilot study of 13 overweight or obese adults randomized to a control group or a novel weight-loss intervention. Results: Compared to controls, intervention participants achieved significant weight loss (−6.3±1.0 kg versus +2.1±1.1 kg, P<0.001) and had increased activation for LC food images with a composition consistent with that recommended in the behavioral intervention at 6 months versus baseline in the right ventral putamen (P=0.04), decreased activation for HC images of typically consumed foods in the left dorsal putamen (P=0.01). There was also a large significant shift in relative activation favoring LC versus HC foods in both regions (P<0.04). Conclusions: This study provides the first demonstration of a positive shift in activation of the reward system toward healthy versus unhealthy food cues in a behavioral intervention, suggesting new avenues to enhance behavioral treatments of obesity
Negotiating daughterhood and strangerhood: retrospective accounts of serial migration
Most considerations of daughtering and mothering take for granted that the subjectivities of mothers and daughters are negotiated in contexts of physical proximity throughout daughters’ childhoods. Yet many mothers and daughters spend periods separated from each other, sometimes across national borders. Globally, an increasing number of children experience life in transnational families.
This paper examines the retrospective narratives of four women who were serial migrants as children (whose parents migrated before they did) . It focuses on their accounts of the reunion with their mothers and how these fit with the ways in which they construct their mother-daughter relationships. We take a psychosocial approach by using a psychoanalytically-informed reading of these narratives to acknowledge the complexities of the attachments produced in the context of migration and to attend to the multi-layered psychodynamics of the resulting relationships. The paper argues that serial migration positioned many of the daughters in a conflictual emotional landscape from which they had to negotiate ‘strangerhood’ in the context of sadness at leaving people to whom they were attached in order to join their mothers (or parents). As a result, many were resistant to being positioned as daughters, doing daughtering and being mothered in their new homes
Till death (or an intruder) do us part: intrasexual-competition in a monogamous Primate
Polygynous animals are often highly dimorphic, and show large sex-differences in the degree of intra-sexual competition and aggression, which is associated with biased operational sex ratios (OSR). For socially monogamous, sexually monomorphic species, this relationship is less clear. Among mammals, pair-living has sometimes been assumed to imply equal OSR and low frequency, low intensity intra-sexual competition; even when high rates of intra-sexual competition and selection, in both sexes, have been theoretically predicted and described for various taxa. Owl monkeys are one of a few socially monogamous primates. Using long-term demographic and morphological data from 18 groups, we show that male and female owl monkeys experience intense intra-sexual competition and aggression from solitary floaters. Pair-mates are regularly replaced by intruding floaters (27 female and 23 male replacements in 149 group-years), with negative effects on the reproductive success of both partners. Individuals with only one partner during their life produced 25% more offspring per decade of tenure than those with two or more partners. The termination of the pair-bond is initiated by the floater, and sometimes has fatal consequences for the expelled adult. The existence of floaters and the sporadic, but intense aggression between them and residents suggest that it can be misleading to assume an equal OSR in socially monogamous species based solely on group composition. Instead, we suggest that sexual selection models must assume not equal, but flexible, context-specific, OSR in monogamous species.Wenner-Gren Foundation, L.S.B. Leakey Foundation, the National Geographic Society, National
Science Foundation (BCS- 0621020), the University of Pennsylvania Research Foundation and the Zoological Society of San Diego, German
Science Foundation (HU 1746-2/1
Canine respiratory coronavirus employs caveolin-1-mediated pathway for internalization to HRT-18G cells
Canine respiratory coronavirus (CRCoV), identified in 2003, is a member of the Coronaviridae family. The virus is a betacoronavirus and a close relative of human coronavirus OC43 and bovine coronavirus. Here, we examined entry of CRCoV into human rectal tumor cells (HRT-18G cell line) by analyzing co-localization of single virus particles with cellular markers in the presence or absence of chemical inhibitors of pathways potentially involved in virus entry. We also targeted these pathways using siRNA. The results show that the virus hijacks caveolin-dependent endocytosis to enter cells via endocytic internalization
Associations between police harassment and distrust in and reduced access to healthcare among Black sexual minority men: A longitudinal analysis of HPTN 061
Objective: Evaluate associations between racialized and homophobia-based police harassment (RHBPH) and healthcare distrust and utilization among Black Sexual Minority Men (BSMM). Methods: We utilized data from a longitudinal cohort study from HIV Prevention Trials Network (HPTN) 061 with baseline, six and 12 month follow-up assessments. Using multivariable analysis, we evaluated associations between RHBPH and healthcare distrust and utilization reported at the 6 and 12 month visits. Results: Of 1553 BSMM present at baseline, 1160 were available at six-month follow-up. In multivariable analysis, increasing frequency of RHBPH was associated with increasing levels of distrust in healthcare providers (aOR 1.31, 95% CI: 1.00, 1.74) and missing 50% or more of healthcare visits at six-month follow-up (aOR 1.93, 95% CI: 1.09, 3.43). Conclusions: Recent experiences of RHBPH are associated with reduced trust in and access to healthcare among BSMM, with more frequent RHBPH associated with greater vulnerability.</p
Visually Driven Activation in Macaque Areas V2 and V3 without Input from the Primary Visual Cortex
Creating focal lesions in primary visual cortex (V1) provides an opportunity to study the role of extra-geniculo-striate pathways for activating extrastriate visual cortex. Previous studies have shown that more than 95% of neurons in macaque area V2 and V3 stop firing after reversibly cooling V1 [1], [2], [3]. However, no studies on long term recovery in areas V2, V3 following permanent V1 lesions have been reported in the macaque. Here we use macaque fMRI to study area V2, V3 activity patterns from 1 to 22 months after lesioning area V1. We find that visually driven BOLD responses persist inside the V1-lesion projection zones (LPZ) of areas V2 and V3, but are reduced in strength by ∼70%, on average, compared to pre-lesion levels. Monitoring the LPZ activity over time starting one month following the V1 lesion did not reveal systematic changes in BOLD signal amplitude. Surprisingly, the retinotopic organization inside the LPZ of areas V2, V3 remained similar to that of the non-lesioned hemisphere, suggesting that LPZ activation in V2, V3 is not the result of input arising from nearby (non-lesioned) V1 cortex. Electrophysiology recordings of multi-unit activity corroborated the BOLD observations: visually driven multi-unit responses could be elicited inside the V2 LPZ, even when the visual stimulus was entirely contained within the scotoma induced by the V1 lesion. Restricting the stimulus to the intact visual hemi-field produced no significant BOLD modulation inside the V2, V3 LPZs. We conclude that the observed activity patterns are largely mediated by parallel, V1-bypassing, subcortical pathways that can activate areas V2 and V3 in the absence of V1 input. Such pathways may contribute to the behavioral phenomenon of blindsight
Dominance hierarchies and social structure in captive groups of the Mozambique tilapia Oreochromis mossambicus
Single-cell RNA-seq supports a developmental hierarchy in human oligodendroglioma
Although human tumours are shaped by the genetic evolution of cancer cells, evidence also suggests that they display hierarchies related to developmental pathways and epigenetic programs in which cancer stem cells (CSCs) can drive tumour growth and give rise to differentiated progeny. Yet, unbiased evidence for CSCs in solid human malignancies remains elusive. Here we profile 4,347 single cells from six IDH1 or IDH2 mutant human oligodendrogliomas by RNA sequencing (RNA-seq) and reconstruct their developmental programs from genome-wide expression signatures. We infer that most cancer cells are differentiated along two specialized glial programs, whereas a rare subpopulation of cells is undifferentiated and associated with a neural stem cell expression program. Cells with expression signatures for proliferation are highly enriched in this rare subpopulation, consistent with a model in which CSCs are primarily responsible for fuelling the growth of oligodendroglioma in humans. Analysis of copy number variation (CNV) shows that distinct CNV sub-clones within tumours display similar cellular hierarchies, suggesting that the architecture of oligodendroglioma is primarily dictated by developmental programs. Subclonal point mutation analysis supports a similar model, although a full phylogenetic tree would be required to definitively determine the effect of genetic evolution on the inferred hierarchies. Our single-cell analyses provide insight into the cellular architecture of oligodendrogliomas at single-cell resolution and support the cancer stem cell model, with substantial implications for disease management
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