Blunted startle reactivity in everyday sadism and psychopathy.

Two studies examined the amplitude of the startle response as a function of the Dark Tetrad of personality (narcissism, Machiavellianism, psychopathy, and sadism). We measured electromyographic activity of the orbicularis oculi muscle evoked by a startle stimulus while participants viewed images on a computer screen. Both studies revealed a negative correlation between general startle reactivity (averaged across positive, negative, and neutral images) and sadistic tendencies.

Preptin Deficiency Does Not Protect against High-Fat Diet-Induced Metabolic Dysfunction or Bone Loss in Mice.

Preptin is derived from the cleavage of the E-peptide of pro-insulin-like growth factor (IGF)-II and is an insulin secretagogue. Observational studies have linked elevated circulating preptin to metabolic dysfunction in humans; however, a causal role for preptin in metabolic dysfunction has not been established. Additionally, preptin can promote osteoblast proliferation and differentiation, suggesting a link with skeletal health.

Combined Growth Factor Hydrogel Enhances Rotator Cuff Enthesis Healing in Rat But Not Sheep Model.

We hypothesized that a combined growth factor hydrogel would improve chronic rotator cuff tear healing in a rat and sheep model. Insulin-like growth factor 1, transforming growth factor β1, and parathyroid hormone were combined into a tyraminated poly-vinyl-alcohol (PVA-Tyr) hydrogel and applied directly at the enthesis. In total, 30 Sprague-Dawley rats and 16 Romney ewes underwent unilateral rotator cuff tenotomy and then delayed repairs were performed after 3-4 weeks.

Dietary supplementation of clinically utilized PI3K p110α inhibitor extends the lifespan of male and female mice.

Diminished insulin and insulin-like growth factor-1 signaling extends the lifespan of invertebrates; however, whether it is a feasible longevity target in mammals is less clear. Clinically utilized therapeutics that target this pathway, such as small-molecule inhibitors of phosphoinositide 3-kinase p110α (PI3Ki), provide a translatable approach to studying the impact of these pathways on aging. Here, we provide evidence that dietary supplementation with the PI3Ki alpelisib from middle age extends the median and maximal lifespan of mice, an effect that was more pronounced in females.

Genetic ablation of the preptin-coding portion of impairs pancreatic function in female mice.

Preptin is a 34-amino acid peptide derived from the E-peptide of pro-insulin-like growth factor 2 and is co-secreted with insulin from β-cells. Little is understood about the effects of endogenous preptin on whole body glucose metabolism. We developed a novel mouse model in which the preptin portion of was genetically ablated in all tissues, hereafter referred to as preptin knockout (KO), and tested the hypothesis that the removal of preptin will lead to a decreased insulin response to a metabolic challenge.

Whole-slide imaging and a Fiji-based image analysis workflow of immunohistochemistry staining of pancreatic islets.

Quantification of cell populations in tissue sections is frequently examined in studies of human disease. However, traditional manual imaging of sections stained with immunohistochemistry is laborious, time-consuming, and often assesses fields of view rather than the whole tissue section. The analysis is usually manual or utilises expensive proprietary image analysis platforms.

Cystinosin-deficient rats recapitulate the phenotype of nephropathic cystinosis.

The lysosomal storage disease cystinosis is caused by mutations in , encoding the cystine transporter cystinosin, and in its severest form leads to proximal tubule dysfunction followed by kidney failure. Patients receive the drug-based therapy cysteamine from diagnosis. However, despite long-term treatment, cysteamine only slows the progression of end-stage renal disease.

The Impact of Maternal High-Fat Diet on Bone Microarchitecture in Offspring.

The incidence of obesity in women of reproductive age has significantly increased over the past 100 years. There is a well-established connection between maternal obesity during pregnancy and an increased risk of developing non-communicable cardiometabolic diseases in her offspring. This mini-review focuses on evidence examining the effect of maternal high-fat diet (HFD) on skeletal development and bone health in later life in offspring.

Sexually dimorphic changes in the endocrine pancreas and skeletal muscle in young adulthood following intra-amniotic IGF-I treatment of growth-restricted fetal sheep.

Fetal growth restriction (FGR) is associated with decreased insulin secretory capacity and decreased insulin sensitivity in muscle in adulthood. We investigated whether intra-amniotic IGF-I treatment in late gestation mitigated the adverse effects of FGR on the endocrine pancreas and skeletal muscle at 18 mo of age. Singleton-bearing ewes underwent uterine artery embolization between 103 and 107 days of gestational age, followed by 5 once-weekly intra-amniotic injections of 360-µg IGF-I (FGRI) or saline (FGRS) and were compared with an unmanipulated control group (CON).

Heterogeneity of murine periosteum progenitors involved in fracture healing.

The periosteum is the major source of cells involved in fracture healing. We sought to characterize progenitor cells and their contribution to bone fracture healing. The periosteum is highly enriched with progenitor cells, including Sca1 cells, fibroblast colony-forming units, and label-retaining cells compared to the endosteum and bone marrow.

Markers for Identification of Postnatal Skeletal Stem Cells In Vivo.

Purpose Of Review: The adult skeleton contains stem cells involved in growth, homeostasis, and healing. Mesenchymal or skeletal stem cells are proposed to provide precursors to osteoblasts, chondrocytes, marrow adipocytes, and stromal cells. We review the evidence for existence and functionality of different skeletal stem cell pools, and the tools available for identifying or targeting these populations in mouse and human tissues.

Internet trolling and everyday sadism: Parallel effects on pain perception and moral judgment.

Objective: This research seeks to clarify the association between online trolling and sadistic personality, and to provide evidence that the reward and rationalization processes at work in sadism are likewise manifest in online trolling.

Method: Online respondents (community adults and university students; total N = 1,715) completed self-report measures of personality and trolling behavior. They subsequently engaged in one of two judgment tasks.

Dispositional malevolence and impression formation: Dark Tetrad associations with accuracy and positivity in first impressions.

Objective: The Dark Tetrad traits (subclinical psychopathy, narcissism, Machiavellianism, and everyday sadism) have interpersonal consequences. At present, however, how these traits are associated with the accuracy and positivity of first impressions is not well understood. The present article addresses three primary questions.

Determining insulin sensitivity from glucose tolerance tests in sheep.

A mathematical model of the dynamics of insulin and glucose during a frequently sampled intravenous glucose tolerance test (IVGTT) in sheep was developed that characterizes the large second-phase insulin secretion response in sheep during IVGTT. The model was fit to measurements of the glucose and insulin dynamics during standard IVGTT ( = 42) and modified IVGTT ( = 40), where insulin was injected 60 min after the initiation of the IVGTT. The correlation between log insulin sensitivity determined by hyperglycemic clamps (HGC) and standard IVGTT was = 0.

Twin Conception in Sheep Leads to Impaired Insulin Sensitivity and Sexually Dimorphic Adipose Tissue and Skeletal Muscle Phenotypes in Adulthood.

Twins are often born small and early and have increased risk of obesity and diabetes later in life. Twin conception in sheep, regardless of whether the pregnancy continues as twins or is reduced to singleton in early gestation, alters offspring growth trajectory and body composition in young adulthood. We hypothesized that twin conception would result in insulin resistance in adulthood, with insulin-resistant adipose tissue and skeletal muscle phenotypes.

Individual differences in activation of the parental care motivational system: assessment, prediction, and implications.

We report on the development, validation, and utility of a measure assessing individual differences in activation of the parental care motivational system: The Parental Care and Tenderness (PCAT) questionnaire. Results from 1,608 adults (including parents and nonparents) show that the 25-item PCAT measure has high internal consistency, high test-retest reliability, high construct validity, and unique predictive utility. Among parents, it predicted self-child identity overlap and caring child-rearing attitudes; among nonparents, it predicted desire to have children.

Behavioral confirmation of everyday sadism.

Past research on socially aversive personalities has focused on subclinical psychopathy, subclinical narcissism, and Machiavellianism-the "Dark Triad" of personality. In the research reported here, we evaluated whether an everyday form of sadism should be added to that list. Acts of apparent cruelty were captured using two laboratory procedures, and we showed that such behavior could be predicted with two measures of sadistic personality.