Is sarcoma a complication of arterial femoro-popliteal bypass?

Angiosarcoma is a rare neoplasm comprising 1 to 2% of soft tissue sarcoma. This tumor has been associated with previous irradiation, exposure to toxins and the presence of foreign bodies. A case report of an epithelioid angiosarcoma that developed at the site of an arterial femoro-popliteal bypass using autologous vein is described. The initial presentation looked like a painful popliteal cyst. Chronic fibrosis secondary to the thrombosis could play a role in the tumorogenesis of this uncommon tumor. This case illustrates that sarcoma may be a late complication of vascular bypass and may have a rheumatologic presentation.     

Human eosinophils express and release IL-13 following CD28-dependent activation

Human eosinophils produce a large number of cytokines, including immunoregulatory cytokines. Given that eosinophils store and release interleukin (IL)-4, a key cytokine in the pathogenesis of allergic inflammation, and that IL-4 and IL-13 share common biological functions, we investigated the possibility that IL-13 may be synthesized by these cells. Using flow cytometry and immunocytochemistry, we show that eosinophils synthesize and store IL-13. Granule localization was demonstrated after subcellular fractionation, and IL-13 immunoreactivity was localized to crystalloid, granule-enriched fractions. Furthermore, electron microscopic analyses specifically localized IL-13 to the dense cores of bicompartmental secondary granules. Upon CD28 ligation, IL-13 was released by eosinophils, whereas a combination of CD28 and immunoglobulin A complexes resulted in decreased IL-13 secretion. Furthermore, eosinophil-derived IL-13 exerts a biological effect, inducing CD23 expression on B cells. By having the capacity to synthesize and release IL-13, eosinophils may participate in the development and maintenance of the T helper cell type 2 response, a prominent feature of allergic diseases.     

Prevalence of hypertension and cardiovascular risk factors among long‐term AIDS survivors: A report from the field

HIV infection is associated with increased risk and progression of cardiovascular disease (CVD), yet little is known about the prevalence of CVD risk factors among long‐term AIDS survivors in resource‐limited settings. Using routinely collected data, we conducted a retrospective study to describe the prevalence of CVD risk factors among a cohort of HIV‐infected patients followed for over 10 years in Port‐au Prince, Haiti. This cohort includes 910 adults who initiated antiretroviral therapy (ART) between 2003 and 2004 and remained in care between 2014 and 2016 when routine screening for CVD risk factors was implemented at a large clinic in Haiti. A total of 397 remained in care ≥10 years and received screening. At ART initiation, 59% were female, median age was 38 years (IQR 33‐44), and median CD4 count was 117 cells/mm³ (IQR 34‐201). Median follow‐up time from ART initiation was 12.1 years (IQR 11.7‐12.7). At screening, median CD4 count was 574 cells/mm³ (IQR 378‐771), and 84% (282 of 336 screened) had HIV‐1 RNA < 1000 copies/mL. Seventy‐four percent of patients had at least 1 risk factor including 58% (224/385) with hypertension, 8% (24/297) diabetes, 43% (119/275) hypercholesterolemia, 8% (20/248) active smoking, and 10% (25/245) obesity. Factors associated with hypertension were age (adjusted OR 1.06, P < .001) and weight at screening (adjusted OR 1.02, P = .019). Long‐term AIDS survivors have a high prevalence of CVD risk factors, primarily hypertension. Integration of cardiovascular screening and management into routine HIV care is needed to maximize health outcomes among aging HIV patients in resource‐limited settings.     

Peroxisome proliferator-activated receptors alpha and gamma down-regulate allergic inflammation and eosinophil activation

Allergic asthma is characterized by airway hyperresponsiveness, eosinophilia, and mucus accumulation and is associated with increased IgE concentrations. We demonstrate here that peroxisome proliferator-activated receptors (PPARs), PPAR-alpha and PPAR-gamma, which have been shown recently to be involved in the regulation of various cell types within the immune system, decrease antigen-induced airway hyperresponsiveness, lung inflammation, eosinophilia, cytokine production, and GATA-3 expression as well as serum levels of antigen-specific IgE in a murine model of human asthma. In addition, we demonstrate that PPAR-alpha and -gamma are expressed in eosinophils and their activation inhibits in vitro chemotaxis and antibody-dependent cellular cytotoxicity. Thus, PPAR-alpha and -gamma (co)agonists might be of therapeutic interest for the regulation of allergic or inflammatory reactions by targeting both regulatory and effector cells involved in the immune response.