Human Platelet-Derived Growth Factor (PDGF): Amino-Terminal Amino Acid Sequence

Human platelet-derived growth factor (PDGF) obtained from outdated human platelets was subjected to amino-terminal amino acid sequence analysis by automated Edman degradation. Despite the apparent presence of limited proteolytic degradation of the protein derived from this method, the sequence analysis reveals two primary peptide sequences and suggests that active PDGF is composed of two, possibly homologous, peptides linked by a disulfide bond or bonds

Simian sarcoma virus onc gene, v-sis, is derived from the gene (or genes) encoding a platelet-derived growth factor

The transforming protein of a primate sarcoma virus and a platelet-derived growth factor are derived from the same or closely related cellular genes. This conclusion is based on the demonstration of extensive sequence similarity between the transforming protein derived from the simian sarcoma virus onc gene, v-sis, and a human platelet-derived growth factor. The mechanism by which v-sis transforms cells could involve the constitutive expression of a protein with functions similar or identical to those of a factor active transiently during normal cell growth

Association of Biologic Therapy with Coronary Inflammation in Patients with Psoriasis as Assessed by Perivascular Fat Attenuation Index

© 2019 American Medical Association. All rights reserved. Importance: Psoriasis is a chronic inflammatory skin disease associated with increased coronary plaque burden and cardiovascular events. Biologic therapy for psoriasis has been found to be favorably associated with luminal coronary plaque, but it is unclear whether these associations are attributable to direct anti-inflammatory effects on the coronary arteries. Objective: To investigate the association of biologic therapy with coronary inflammation in patients with psoriasis using the perivascular fat attenuation index (FAI), a novel imaging biomarker that assesses coronary inflammation by mapping spatial changes of perivascular fat composition via coronary computed tomography angiography (CCTA). Design, Setting, and Participants: This prospective cohort study performed from January 1, 2013, through March 31, 2019, analyzed changes in FAI in patients with moderate to severe psoriasis who underwent CCTA at baseline and at 1 year and were not receiving biologic psoriasis therapy at baseline. Exposures: Biologic therapy for psoriasis. Main Outcomes and Measures: Perivascular FAI mapping was performed based on an established method by a reader blinded to patient demographics, visit, and treatment status. Results: Of the 134 patients (mean [SD] age, 51.1 [12.1] years; 84 [62.5%] male), most had low cardiovascular risk by traditional risk scores (median 10-year Framingham Risk Score, 3% [interquartile range, 1%-7%]) and moderate to severe skin disease. Of these patients, 82 received biologic psoriasis therapy (anti-Tumor necrosis factor α, anti-interleukin [IL] 12/23, or anti-IL-17) for 1 year, and 52 did not receive any biologic therapy and were given topical or light therapy (control group). At baseline, 46 patients (27 in the treated group and 19 in the untreated group) had a focal coronary atherosclerotic plaque. Biologic therapy was associated with a significant decrease in FAI at 1 year (median FAI-71.22 HU [interquartile range (IQR),-75.85 to-68.11 HU] at baseline vs-76.09 HU [IQR,-80.08 to-70.37 HU] at 1 year; P \u3c.001) concurrent with skin disease improvement (median PASI, 7.7 [IQR, 3.2-12.5] at baseline vs 3.2 [IQR, 1.8-5.7] at 1 year; P \u3c.001), whereas no change in FAI was noted in those not receiving biologic therapy (median FAI,-71.98 [IQR,-77.36 to-65.64] at baseline vs-72.66 [IQR,-78.21 to-67.44] at 1 year; P =.39). The associations with FAI were independent of the presence of coronary plaque and were consistent among patients receiving different biologic agents, including anti-Tumor necrosis factor α (median FAI,-71.25 [IQR,-75.86 to-66.89] at baseline vs-75.49 [IQR,-79.12 to-68.58] at 1 year; P \u3c.001) and anti-IL-12/23 or anti-IL-17 therapy (median FAI,-71.18 [IQR,-75.85 to-68.80] at baseline vs-76.92 [IQR,-81.16 to-71.67] at 1 year; P \u3c.001). Conclusions and Relevance: In this study, biologic therapy for moderate to severe psoriasis was associated with reduced coronary inflammation assessed by perivascular FAI. This finding suggests that perivascular FAI measured by CCTA may be used to track response to interventions for coronary artery disease

Expert consensus document: Defining the major health modifiers causing atrial fibrillation: a roadmap to underpin personalized prevention and treatment

Despite remarkable advances in antiarrhythmic drugs, ablation procedures, and stroke-prevention strategies, atrial fibrillation (AF) remains an important cause of death and disability in middle-aged and elderly individuals. Unstructured management of patients with AF sharply contrasts with our detailed, although incomplete, knowledge of the mechanisms that cause AF and its complications. Altered calcium homeostasis, atrial fibrosis and ageing, ion-channel dysfunction, autonomic imbalance, fat-cell infiltration, and oxidative stress, in addition to a susceptible genetic background, contribute to the promotion, maintenance, and progression of AF. However, clinical management of patients with AF is currently guided by stroke risk parameters, AF pattern, and symptoms. In response to this apparent disconnect between the known pathophysiology of AF and clinical management, we propose a roadmap to develop a set of clinical markers that reflect the major causes of AF in patients. Thereby, the insights into the mechanisms causing AF will be transformed into a format that can underpin future personalized strategies to prevent and treat AF, ultimately informing better patient care