The role of focal adhesion kinase in nonmuscle cell contraction

Focal adhesions are specialized cell contact sites of distinct molecular composition and structure that bridge the actin cytoskeleton to the extracellular matrix and provide for efficient bidirectional transmission of biochemical and mechanical signals between the intra- and extracellular compartment. Many proteins within the focal adhesion have been discovered to be an integral component of the adhesion structure and function; however, a key molecule in the organization and physiological activity of focal adhesions is focal adhesion kinase (FAK). FAK is a nonreceptor tyrosine kinase that is essential for cell processes including cell migration, growth, and survival. Due to its connection between the cytoskeleton and extracellular matrix, FAK has been proposed to be a key component of integrin downstream signaling that regulates the organization of actin for transduction of cellular forces from inside to outside of the cell. While many studies have focused on determining FAK\u27s role in sensing mechanical forces and regulating contractile signaling pathways, very few studies have attempted to determine the role of FAK in cell contraction through direct measurement of cellular tension. Therefore, the role of FAK in fibroblast and endothelial cell contractility was determined.;To investigate the role of FAK in endothelial cell tension and monolayer permeability, a stable FAK knockdown human pulmonary microvessel endothelial cell line (FAK-KD) was generated. Knockdown of FAK altered both cell morphology and actin distribution, and increased focal adhesion formation and VE-cadherin localization to cell-cell contacts. Measurement of tension produced by cells embedded within a three-dimensional (3-D) collagen matrix revealed that loss of FAK increased basal tension without alterations in basal myosin phosphorylation. Agonist-induced force was unaffected. However, loss of FAK enhanced endothelial monolayer barrier function. Thus, FAK is responsible for the balance between cellmatrix and cell-cell cohesion in order to regulate endothelial cell tension and monolayer permeability.;In order to determine the role of FAK in fibroblast cell contractility, FAK knockout (FAK-KO) mouse embryonic fibroblasts (MEFs) embedded in 3-D collagen gels were utilized. FAK null MEFs produced a decrease in basal tension and minimal agonist induced force compared to controls (FAK-WT). However, myosin II phosphorylation was comparable between FAK-KO and FAK-WT MEFs. Investigation of the collagen matrix revealed that FAKKO MEFs had an inability to organize their collagen matrix. Inhibition of FAK kinase activity or expression of FAK mutants revealed that FAK kinase activity was dispensable for tension generation. Thus, FAK localization to the focal adhesion was critical in the transmission of internal force to the collagen matrix resulting in cell contraction.;Collectively, these data show that FAK is an integral part in nonmuscle cellular tension. Although the loss of FAK altered tension generation differently in fibroblasts and endothelial cells, the differences in each cell\u27s physiological function may explain why FAK regulates cell tension differently. Nevertheless, FAK is an important molecular player in focal adhesions facilitating the transduction of forces from inside to outside of the cell and may be a novel target in the development of treatments to control cell contractility

Hot topics, urgent priorities, and ensuring success for racial/ethnic minority young investigators in academic pediatrics.

BackgroundThe number of racial/ethnic minority children will exceed the number of white children in the USA by 2018. Although 38% of Americans are minorities, only 12% of pediatricians, 5% of medical-school faculty, and 3% of medical-school professors are minorities. Furthermore, only 5% of all R01 applications for National Institutes of Health grants are from African-American, Latino, and American Indian investigators. Prompted by the persistent lack of diversity in the pediatric and biomedical research workforces, the Academic Pediatric Association Research in Academic Pediatrics Initiative on Diversity (RAPID) was initiated in 2012. RAPID targets applicants who are members of an underrepresented minority group (URM), disabled, or from a socially, culturally, economically, or educationally disadvantaged background. The program, which consists of both a research project and career and leadership development activities, includes an annual career-development and leadership conference which is open to any resident, fellow, or junior faculty member from an URM, disabled, or disadvantaged background who is interested in a career in academic general pediatrics.MethodsAs part of the annual RAPID conference, a Hot Topic Session is held in which the young investigators spend several hours developing a list of hot topics on the most useful faculty and career-development issues. These hot topics are then posed in the form of six "burning questions" to the RAPID National Advisory Committee (comprised of accomplished, nationally recognized senior investigators who are seasoned mentors), the RAPID Director and Co-Director, and the keynote speaker.Results/conclusionsThe six compelling questions posed by the 10 young investigators-along with the responses of the senior conference leadership-provide a unique resource and "survival guide" for ensuring the academic success and optimal career development of young investigators in academic pediatrics from diverse backgrounds. A rich conversation ensued on the topics addressed, consisting of negotiating for protected research time, career trajectories as academic institutions move away from an emphasis on tenure-track positions, how "non-academic" products fit into career development, racism and discrimination in academic medicine and how to address them, coping with isolation as a minority faculty member, and how best to mentor the next generation of academic physicians

The challenge of measuring intra-individual change in fatigue during cancer treatment

Evaluate how well three different patient-reported outcomes (PROs) measure individual change

Factors associated with posttraumatic stress symptoms in a prospective cohort of patients after abdominal sepsis: a nomogram

Objective: To determine to what extent patients who have survived abdominal sepsis suffer from symptoms of posttraumatic stress disorder (PTSD) and depression, and to identify potential risk factors for PTSD symptoms. Design and setting: PTSD and depression symptoms were measured using the Impact of Events Scale-Revised (IES-R), the Post-Traumatic Symptom Scale 10 (PTSS-10) and the Beck Depression Inventory II (BDI-II). Patients and participants: A total of 135 peritonitis patients were eligible for this study, of whom 107 (80%) patients completed the questionnaire. The median APACHE-II score was 14 (range 12-16), and 89% were admitted to the ICU. Measurements and results: The proportion of patients with "moderate" PTSD symptom scores was 28% (95% CI 20-37), whilst 10% (95% CI 6-17) of patients had "high" PTSD symptom scores. Only 5% (95% CI 2-12) of the patients expressed severe depression symptoms. Factors associated with increased PTSD symptoms in a multivariate ordinal regression model were younger age (0.74 per 10 years older, p = 0.082), length of ICU stay (OR = 1.4 per doubling of duration, p = 0.003) and having some (OR = 4.9, p = 0.06) or many (OR = 55.5, p < 0.001) traumatic memories of the ICU or hospital stay. Conclusion: As many as 38% of patients after abdominal sepsis report elevated levels of PTSD symptoms on at least one of the questionnaires. Our nomogram may assist in identifying patients at increased risk for developing symptoms of PTSD

Promoter DNA Methylation of Oncostatin M receptor-β as a Novel Diagnostic and Therapeutic Marker in Colon Cancer

In addition to genetic changes, the occurrence of epigenetic alterations is associated with accumulation of both genetic and epigenetic events that promote the development and progression of human cancer. Previously, we reported a set of candidate genes that comprise part of the emerging “cancer methylome”. In the present study, we first tested 23 candidate genes for promoter methylation in a small number of primary colon tumor tissues and controls. Based on these results, we then examined the methylation frequency of Oncostatin M receptor-β (OSMR) in a larger number of tissue and stool DNA samples collected from colon cancer patients and controls. We found that OSMR was frequently methylated in primary colon cancer tissues (80%, 80/100), but not in normal tissues (4%, 4/100). Methylation of OSMR was also detected in stool DNA from colorectal cancer patients (38%, 26/69) (cut-off in TaqMan-MSP, 4). Detection of other methylated markers in stool DNA improved sensitivity with little effect on specificity. Promoter methylation mediated silencing of OSMR in cell lines, and CRC cells with low OSMR expression were resistant to growth inhibition by Oncostatin M. Our data provide a biologic rationale for silencing of OSMR in colon cancer progression and highlight a new therapeutic target in this disease. Moreover, detection and quantification of OSMR promoter methylation in fecal DNA is a highly specific diagnostic biomarker for CRC

Re-visiting Meltsner: Policy Advice Systems and the Multi-Dimensional Nature of Professional Policy Analysis

10.2139/ssrn.15462511-2

Transcriptional Landscape of the Prenatal Human Brain

Summary The anatomical and functional architecture of the human brain is largely determined by prenatal transcriptional processes. We describe an anatomically comprehensive atlas of mid-gestational human brain, including de novo reference atlases, in situ hybridization, ultra-high resolution magnetic resonance imaging (MRI) and microarray analysis on highly discrete laser microdissected brain regions. In developing cerebral cortex, transcriptional differences are found between different proliferative and postmitotic layers, wherein laminar signatures reflect cellular composition and developmental processes. Cytoarchitectural differences between human and mouse have molecular correlates, including species differences in gene expression in subplate, although surprisingly we find minimal differences between the inner and human-expanded outer subventricular zones. Both germinal and postmitotic cortical layers exhibit fronto-temporal gradients, with particular enrichment in frontal lobe. Finally, many neurodevelopmental disorder and human evolution-related genes show patterned expression, potentially underlying unique features of human cortical formation. These data provide a rich, freely-accessible resource for understanding human brain development

Identification of 12 new susceptibility loci for different histotypes of epithelial ovarian cancer.

To identify common alleles associated with different histotypes of epithelial ovarian cancer (EOC), we pooled data from multiple genome-wide genotyping projects totaling 25,509 EOC cases and 40,941 controls. We identified nine new susceptibility loci for different EOC histotypes: six for serous EOC histotypes (3q28, 4q32.3, 8q21.11, 10q24.33, 18q11.2 and 22q12.1), two for mucinous EOC (3q22.3 and 9q31.1) and one for endometrioid EOC (5q12.3). We then performed meta-analysis on the results for high-grade serous ovarian cancer with the results from analysis of 31,448 BRCA1 and BRCA2 mutation carriers, including 3,887 mutation carriers with EOC. This identified three additional susceptibility loci at 2q13, 8q24.1 and 12q24.31. Integrated analyses of genes and regulatory biofeatures at each locus predicted candidate susceptibility genes, including OBFC1, a new candidate susceptibility gene for low-grade and borderline serous EOC