Brain drain

Brain drain is a well-established concept in migration studies. Originally coined in the 1960s, the term refers to profoundly negative effects of large-scale emigration of skilled workers, especially in low-income economies. The terminologies on brain mobility have proliferated to include notions such as brain circulation and brain chains for analysing increasingly transient and multidirectional movements of skilled people in the context of globalization. The notion of brain drain remains important for identifying uneven development through skills migration and the creation of policies and strategies for mitigating resulting detrimental effects, whether at the level of supranational regions and states, or more recently, sub-national regions, cities, places, and institutions. Global patterns of migration indicate substantial loss of talent for some countries and gain for others, whereas empirical findings on the motivations, experiences, and outcomes of brain drain, gain, and circulation paint a more nuanced picture of changing mobilities and networks. Recent conceptual debates in human geography suggest to situate brain drain within wider brain chains to provide more holistic views on skilled migrants’ journeys, from first considerations of emigration via the route taken to settlement, commuting practices, and potential return, including involved and affected people, institutions, infrastructures, and im/materialities

Reduced placental taurine transporter (TauT) activity in pregnancies complicated by pre-eclampsia and maternal obesity.

Taurine is an important nutrient in intrauterine life, being required for fetal organ development and cellular renewal of syncytiotrophoblast (STB), the nutrient transport epithelium of the placenta. As taurine is conditionally essential in human pregnancy, the fetal and placental demand for taurine is met by uptake from maternal blood into STB through the activity of TauT. Pre-eclampsia (PE) and maternal obesity are serious complications of pregnancy, associated with fetal growth restriction (FGR) and abnormal renewal of STB, and maternal obesity is a major risk factor for PE. Here we test the hypothesis that STB TauT activity is reduced in maternal obesity and PE compared to normal pregnancy. STB TauT activity, measured in fragments of placental tissue, was negatively related to maternal BMI over the range 18–46 kg/m(2) in both the first trimester (7–12 weeks gestation) and at term (p < 0.01; linear regression). Neither TauT activity nor expression in the first trimester differed to normal pregnancy at term. STB TauT activity was significantly lower in PE than normal pregnancy (p < 0.01). Neuropeptide Y (NPY), a protein kinase C (PKC) activator which is elevated in PE and obesity, reduced STB TauT activity by 20% (50 pM–50 nM: 2 h) (p < 0.03). Activation of PKC by phorbol 12-myristate-13-acetate (1 μM) reduced TauT activity by 18% (p < 0.05). As TauT activity is inhibited by phosphorylation, we propose that NPY activates PKC in the STB which phosphorylates TauT in PE and maternal obesity. Reduced TauT activity could contribute to dysregulated renewal of STB and FGR that are common to PE and maternal obesity

RAS Mutation Predicts Positive Resection Margins and Narrower Resection Margins in Patients Undergoing Resection of Colorectal Liver Metastases

Background: In patients undergoing resection of colorectal liver metastases (CLM), resection margin status is a significant predictor of survival, particularly in patients with suboptimal response to preoperative therapy. RAS mutations have been linked to more invasive and migratory tumor biology and poor response to modern chemotherapy. Objective. The aim of this study was to evaluate the relationship between RAS mutation and resection margin status in patients undergoing resection of CLM. Methods: Patients who underwent curative resection of CLM from 2005 to 2013 with known RAS mutation status were identified from a prospectively maintained database. A positive margin was defined as tumor cells\1 mm from the parenchymal transection line. Results: The study included 633 patients, of whom 229 (36.2 %) had mutant RAS. The positive margin rate was 11.4 % (26/229) for mutant RAS and 5.4 % (22/404) for wild-type RAS (p = 0.007). In multivariate analysis, the only factors associated with a positive margin were RAS mutation (hazard ratio [HR] 2.439; p = 0.005) and carcinoembryonic antigen level 4.5 ng/mL or greater (HR 2.060; p = 0.026). Among patients presenting with liver- first recurrence during follow-up, those with mutant RAS had narrower margins at initial CLM resection (median 4 mm vs. 7 mm; p = 0.031). A positive margin (HR 3.360; p\0.001) and RAS mutation (HR 1.629; p = 0.044) were independently associated with worse overall survival. Conclusion: RAS mutations are associated with positive margins in patients undergoing resection of CLM. Tumors with RAS mutation should prompt careful efforts to achieve negative resection margins