Sticky Floor and Glass Ceilings in Academic Medicine: Analysis of Race and Gender.

Purpose This paper examines the changes in the representation of women and racial minorities in academic medicine, compares the proportion of minorities in medicine and the general United States (US) population, and discusses potential explanations for observed trends. Methods A retrospective cross-sectional analysis of the Association of American Medical Colleges (AAMC) database was done and used to collect data on the gender and race of physicians in academic medicine. Data was collected for instructors, assistant professors, associate professors, full professors, and chairpersons from 2007 to 2018, and trends were presented. Results White physicians represented most academic physicians at every academic level, peaking in proportion at 82.74% of chairpersons and were lowest at the level of instructor at 59.30%. A similar distribution existed when gender was compared, with men comprising 84.67% of chairpersons and forming the majority at levels of full, associate, and assistant professors. However, most physicians at the level of instructors are women at 55.44%. Conclusions Though women and racial minorities have gained greater representation in academic medicine over the past decade, high-level academic positions are not as accessible to them. Existing efforts of advocacy for women and minority races have proven fruitful over the past decade, but much more work needs to be done.

Cathelicidin modulates synthesis of Toll-like Receptors (TLRs) 4 and 9 in colonic epithelium.

Cathelicidin are innate antimicrobial peptides with broad immunomodulatory functions; however, their role in regulating intestinal defenses is not well characterized. This study aimed to investigate the role of cathelicidin modulating expression of Toll-like receptors (TLRs) 4 and 9 in colonic epithelium in response to bacterial patterns. We demonstrated herein that intestinal epithelial cells, when primed by bacterial lipopolysaccharide (LPS), responded to cathelicidin by increased transcription and protein synthesis of TLR4. This cathelicidin-induced response required the interaction of LPS-TLR4 and activation of MAPK signalling pathways. However, cathelicidin blocked TLR9 responses induced by TLR9 ligand CpG oligodeoxynucleotide (CpG ODN) in these colonic epithelial cells. Modulations of TLRs triggered by cathelicidin in intestinal epithelium occurred mainly in the apical compartment of intestinal cells. Activation of TLR4 by ligands in combination with cathelicidin promoted CXCL8 chemokine secretion and epithelial antimicrobial defenses against Escherichia coli. We concluded that cathelicidin selectively modulated synthesis of TLR4 and 9 in intestinal epithelium, but only when cells were exposed to virulence factors, mostly from apical surfaces. Enhanced TLR4 expression promoted by cathelicidin in intestinal epithelium may be crucial for controlling enteric infectious diseases.

Proline-arginine rich (PR-39) cathelicidin: Structure, expression and functional implication in intestinal health.

Proline-Arginine-39 (PR-39) is a small cationic, proline and arginine rich, cathelicidin that plays an important role in the porcine innate immune system. Although PR-39 was first discovered in intestinal cell lysates of pigs, subsequent research has indicated that it is primarily expressed in bone marrow and other lymphoid tissues including the thymus and spleen, as well as in leukocytes. Mature PR-39 cathelicidin has anti-microbial activity against many gram-negative and some gram-positive bacteria. PR-39 is also a bridge between the innate and adaptive immune system with recognized immunomodulatory, wound healing, anti-apoptotic, and pro-angiogenic functions. The purpose of this review is to summarize our current knowledge about the structure, expression, and functions of PR-39 and its potential to promote intestinal homeostasis. This understanding is relevant in the search of alternative therapeutics against diarrheic enterocolitis, a major problem faced by pork producers both in terms of costs and risk of zoonosis.