Johns Hopkins University School of Medicine

About: Johns Hopkins University School of Medicine is a healthcare organization based out in Baltimore, Maryland, United States. It is known for research contribution in the topics: Population & Medicine. The organization has 44277 authors who have published 79222 publications receiving 4788882 citations.

Sphingosine 1-phosphate promotes endothelial cell barrier integrity by Edg-dependent cytoskeletal rearrangement

Abstract: Substances released by platelets during blood clotting are essential participants in events that link hemostasis and angiogenesis and ensure adequate wound healing and tissue injury repair. We assessed the participation of sphingosine 1-phosphate (Sph-1-P), a biologically active phosphorylated lipid growth factor released from activated platelets, in the regulation of endothelial monolayer barrier integrity, which is key to both angiogenesis and vascular homeostasis. Sph-1-P produced rapid, sustained, and dose-dependent increases in transmonolayer electrical resistance (TER) across both human and bovine pulmonary artery and lung microvascular endothelial cells. This substance also reversed barrier dysfunction elicited by the edemagenic agent thrombin. Sph-1-P-mediated barrier enhancement was dependent upon G(ialpha)-receptor coupling to specific members of the endothelial differentiation gene (Edg) family of receptors (Edg-1 and Edg-3), Rho kinase and tyrosine kinase-dependent activation, and actin filament rearrangement. Sph-1-P-enhanced TER occurred in conjunction with Rac GTPase- and p21-associated kinase-dependent endothelial cortical actin assembly with recruitment of the actin filament regulatory protein, cofilin. Platelet-released Sph-1-P, linked to Rac- and Rho-dependent cytoskeletal rearrangement, may act late in angiogenesis to stabilize newly formed vessels, which often display abnormally increased vascular permeability.

Community-Acquired Pneumonia in Adults: Guidelines for Management

Abstract: This is part of the series of practice guidelines commissioned by the Infectious Diseases Society of America through its Practice Guidelines Committee. The purpose of this guideline is to provide assistance to clinicians in the diagnosis and treatment of community-acquired pneumonia. The targeted providers are internists and family practitioners. The targeted groups are immunocompetent adult patients. Criteria are specified for determining whether the inpatient or outpatient setting is appropriate for treatment. Differences from other guidelines written on this topic include use of laboratory criteria for diagnosis and approach to antimicrobial therapy. Panel members and consultants are experts in adult infectious diseases. The guidelines are evidence based where possible. A standard ranking system is used for the strength of the recommendations and the quality of the evidence cited in the literature reviewed. The document has been subjected to external review by peer reviewers as well as by the Practice Guidelines Committee and was approved by the IDSA Council. An executive summary and tables highlight the major recommendations. The guidelines will be listed on the IDSA home page at http://www.idsociety.org.

Race and trust in the health care system.

Abstract: Objective. A legacy of racial discrimination in medical research and the health care system has been linked to a low level of trust in medical research and medical care among African Americans. While racial differences in trust in physicians have been demonstrated, little is known about racial variation in trust of health insurance plans and hospitals. For the present study, the authors analyzed responses to a cross sectional telephone survey to assess the independent relationship of self-reported race (non-Hispanic black or non-Hispanic white) with trust in physicians, hospitals, and health insurance plans. Methods. Respondents ages 18–75 years were asked to rate their level of trust in physicians, health insurance plans, and hospitals. Items from the Medical Mistrust Index were used to assess fear and suspicion of hospitals. Results. Responses were analyzed for 49 (42%) non-Hispanic black and 69 (58%) non-Hispanic white respondents (N=118; 94% of total survey population). A majority of respondents trusted physicians (71%) and hospitals (70%), but fewer trusted their health insurance plans (28%). After adjustment for potential confounders, non-Hispanic black respondents were less likely to trust their physicians than non-Hispanic white respondents (adjusted absolute difference 37%; p=0.01) and more likely to trust their health insurance plans (adjusted absolute difference 28%; p=0.04). The difference in trust of hospitals (adjusted absolute difference 13%) was not statistically significant. Non-Hispanic black respondents were more likely than non-Hispanic white respondents to be concerned about personal privacy and the potential for harmful experimentation in hospitals. Conclusions. Patterns of trust in components of our health care system differ by race. Differences in trust may reflect divergent cultural experiences of blacks and whites as well as differences in expectations for care. Improved understanding of these factors is needed if efforts to enhance patient access to and satisfaction with care are to be effective.

Long-term antidepressant treatment decreases spiroperidol-labeled serotonin receptor binding

Abstract: Antidepressants compete at several neurotransmitter receptor binding site, but drug affinities do not correlate with clinical efficacy. Long-term, but not short-term, antidepressant treatment decreases the numbers of both serotonin and beta-adrenergic receptors. The decrease in the number of receptor sites is most marked for [3H]spiroperidol-labeled serotonin receptors and is characteristic for antidepressants of several classes.