Loneliness predicts reduced physical activity: Cross-sectional & longitudinal analyses.

Objective: To determine cross-sectional and prospective associations between loneliness and physical activity, and to evaluate the roles of social control and emotion regulation as mediators of these associations. Design: A population-based sample of 229 White, Black, and Hispanic men and women, age 50 to 68 years at study onset, were tested annually for each of 3 years. Main Outcome Measures: Physical activity probability, and changes in physical activity probability over a 3-year period. Results: Replicating and extending prior cross-sectional research, loneliness was associated with a significantly reduced odds of physical activity (OR = 0.65 per SD of loneliness) net of sociodemographic variables (age, gender, ethnicity, education, income), psychosocial variables (depressive symptoms, perceived stress, hostility, social support), and self-rated health. This association was mediated by hedonic emotion regulation, but not by social control as indexed by measures of social network size, marital status, contact with close ties, group membership, or religious group affiliation. Longitudinal analyses revealed that loneliness predicted diminished odds of physical activity in the next two years (OR = 0.61), and greater likelihood of transitioning from physical activity to inactivity (OR = 1.58). Conclusion: Loneliness among middle and older age adults is an independent risk factor for physical inactivity and increases the likelihood that physical activity will be discontinued over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Roles of Notch Signaling in the Tumor Microenvironment

The Notch signaling pathway is an architecturally simple signaling mechanism, well known for its role in cell fate regulation during organ development and in tissue homeostasis. In keeping with its importance for normal development, dysregulation of Notch signaling is increasingly associated with different types of tumors, and proteins in the Notch signaling pathway can act as oncogenes or tumor suppressors, depending on the cellular context and tumor type. In addition to a role as a driver of tumor initiation and progression in the tumor cells carrying oncogenic mutations, it is an emerging realization that Notch signaling also plays a role in non-mutated cells in the tumor microenvironment. In this review, we discuss how aberrant Notch signaling can affect three types of cells in the tumor stroma—cancer-associated fibroblasts, immune cells and vascular cells—and how this influences their interactions with the tumor cells. Insights into the roles of Notch in cells of the tumor environment and the impact on tumor-stroma interactions will lead to a deeper understanding of Notch signaling in cancer and inspire new strategies for Notch-based tumor therapy.     

Molecular Effects of Chronic Exposure to Palmitate in Intestinal Organoids: A New Model to Study Obesity and Diabetes

Intestinal cell dysfunctions involved in obesity and associated diabetes could be correlated with impaired intestinal cell development. To date, the molecular mechanisms underlying these dysfunctions have been poorly investigated because of the lack of a good model for studying obesity. The main aim of this study was to investigate the effects of lipotoxicity on intestinal cell differentiation in small intestinal organoid platforms, which are used to analyze the regulation of cell differentiation. Mouse intestinal organoids were grown in the presence/absence of high palmitate concentrations (0.5 mM) for 48 h to simulate lipotoxicity. Palmitate treatment altered the expression of markers involved in the differentiation of enterocytes and goblet cells in the early (Hes1) and late (Muc2) phases of their development, respectively, and it modified enterocytes and goblet cell numbers. Furthermore, the expression of enteroendocrine cell progenitors (Ngn3) and I cells (CCK) markers was also impaired, as well as CCK-positive cell numbers and CCK secretion. Our data indicate, for the first time, that lipotoxicity simultaneously influences the differentiation of specific intestinal cell types in the gut: enterocytes, goblet cells and CCK cells. Through this study, we identified novel targets associated with molecular mechanisms affected by lipotoxicity that could be important for obesity and diabetes therapy.     

Linear friction welding of Ti-6Al-4V parts produced by electron beam melting

The linear friction welding (LFW) of Ti-6Al-4V parts manufactured through electron beam melting (EBM) is investigated using different processing conditions of frequency (from 40 to 50 Hz) and pressure (from 55 to 75 MPa). The microstructure, hardness, and porosity of the different zones of the weld are analyzed in relation to the parent material. The experiments show that LFW is a viable technology for Ti-6Al-4V EBMed parts since it produces welds with hardness and microstructure comparable to those of the base material. Furthermore, the process is demonstrated to be quite robust in the range of specific power input going from ~0.7 to ~1.2 W/mm2. LFW of small EBMed parts to form larger components is of particular interest for the industrialization of titanium alloy aerospace components produced by means of additive manufacturing.     

Effect of saffron addition on the microbiological,physicochemical, antioxidant and sensory characteristics of yoghurt

The impact of added saffron on the characteristics of yoghurt was evaluated during storage. The fat content was lower in the saffron yoghurt. All colour variables were significantly affected by saffron and storage. From the 15th day of storage, bacterial numbers in the saffron yoghurt were higher than those of the control yoghurt. Sensory analysis data suggested that colour, odour and texture impacted consistently on the overall acceptability of the saffron yoghurt. Saffron addition significantly increased polyphenol content and antioxidant activity, providing evidence that the enrichment of natural yoghurt with saffron yields an innovative fermented product useful for supplementing antioxidant dietary intake.     

Age-related changes in cardiovascular response as a function of a chronic stressor and social support.

The effects of aging, chronic stress, and social support on cardiovascular functioning were examined using a cross-sectional design. 36 family caregivers of Alzheimer's disease victims and 34 control Ss performed 2 active coping tasks while continuous noninvasive measures of cardiovascular activity were monitored. Results revealed that caregivers high in social support displayed typical age-related decreases in heart-rate reactivity, whereas caregivers low in social support displayed age-related increases in heart-rate reactivity. Analyses further indicated that only Ss with low social support were characterized by age-related increases in systolic blood pressure. These results suggest that social support can moderate age-related changes in cardiovascular functioning, particularly in Ss exposed to a chronic stressor. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Just because you're imaging the brain doesn't mean you can stop using your head: A primer and set of first principles.

Developments within the neurosciences, cognitive sciences, and social sciences have contributed to the emergence of social neuroscience. Among the most obvious contemporary developments are brain-imaging procedures such as functional magnetic resonance imaging. The authors outline a set of first principles designed to help make sense of brain-imaging research within the fields of cognitive and social neuroscience. They begin with a principle few would debate--that social cognition, emotion, and behavior involve the brain--but whose implications might not be entirely obvious to those new to the field. The authors conclude that (a) complex aspects of the mind and behavior will benefit from yet a broader collaboration of neuroscientists, cognitive scientists, and social scientists, and (b) social psychologists bring important theoretical, methodological, and statistical expertise to this interdisciplinary enterprise. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electromyographic activity over facial muscle regions can differentiate the valence and intensity of affective reactions.

In a pilot study, 16 undergraduates were exposed briefly to slides and tones that were mildly to moderately evocative of positive and negative affect. Facial electromyograph (EMG) activity differentiated both the valence and intensity of the affective reaction. Moreover, 8 independent judges were unable to determine from viewing videotapes of the Ss' facial displays whether a positive or negative stimulus had been presented or whether a mildly or moderately intense stimulus had been presented. In the main experiment, 28 Ss briefly viewed slides of scenes that were mildly to moderately evocative of positive and negative affect. Again, EMGH activity over the brow, eye, and cheek muscle regions differentiated the pleasantness and intensity of Ss' affective reactions to the visual stimuli even though visual inspection of the videotapes again indicated that expressions of emotion were not apparent. Results suggest that gradients of EMGH activity over the muscles of facial expression can provide objective and continuous probes of affective processes that are too subtle or fleeting to evoke expressions observable under normal conditions of social interaction. (76 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Marital conflict and endocrine function: Are men really more physiologically affected than women?

This study assessed marital conflict behavior and endocrine function in 90 newlywed couples. Blood samples acquired hourly from 8:00 a.m. through 10:00 p.m. were combined to provide composite daytime values for 3 stress hormones--epinephrine ( EPI ), norepinephrine ( NEPI ), and cortisol -- and 3 related hormones (ACTH, growth hormone, and prolactin). These pooled data provided a window on endocrine function in couples for whom the day included a conflict. For wives, higher probabilities of husband's withdrawal in response to wife's negative behavior were associated with higher NEPI and cortisol levels. In addition, higher frequencies of positive behaviors were associated with lower EPI and higher prolactin levels among wives. Husbands' endocrine data were not associated with behavioral data. These findings are discussed in the context of gender models of marital conflict. (PsycINFO Database Record (c) 2010 APA, all rights reserved)