Characterisation of the vascular pathology in Sigmodon hispidus (Rodentia: Cricetidae) following experimental infection with Angiostrongylus costaricensis (Nematoda: Metastrongylidae).

BACKGROUND: Angiostrongylus costaricensis is a nematode that causes human abdominal angiostrongyliasis, a disease found mainly in Latin American countries and particularly in Brazil and Costa Rica. Its life cycle involves exploitation of both invertebrate and vertebrate hosts. Its natural reservoir is a vertebrate host, the cotton rat Sigmodon hispidus. The adult worms live in the ileo-colic branches of the upper mesenteric artery of S. hispidus, causing periarteritis. However, there is a lack of data on the development of vasculitis in the course of infection. OBJECTIVE: To describe the histopathology of vascular lesions in S. hispidus following infection with A. costaricensis. METHODS: Twenty-one S. hispidus were euthanised at 30, 50, 90 and 114 days post-infection (dpi), and guts and mesentery (including the cecal artery) were collected. Tissues were fixed in Carson's Millonig formalin, histologically processed for paraffin embedding, sectioned with a rotary microtome, and stained with hematoxylin-eosin, resorcin-fuchsin, Perls, Sirius Red (pH = 10.2), Congo Red, and Azan trichrome for brightfield microscopy analysis. FINDINGS: At 30 and 50 dpi, live eggs and larvae were present inside the vasa vasorum of the cecal artery, leading to eosinophil infiltrates throughout the vessel adventitia and promoting centripetal vasculitis with disruption of the elastic layers. Disease severity increased at 90 and 114 dpi, when many worms had died and the intensity of the vascular lesions was greatest, with intimal alterations, thrombus formation, iron accumulation, and atherosclerosis. CONCLUSION: In addition to abdominal angiostrongyliasis, our data suggest that this model could be very useful for autoimune vasculitis and atherosclerosis studies.

Relationship between carotid intima media thickness and helminth infections on Flores Island, Indonesia.

OBJECTIVE: To examine the association between helminth infections and atherosclerosis. BACKGROUND: Chronic helminth infection, which can lead to poor nutritional status and anti-inflammatory response, might protect against the development of atherosclerosis. METHODS: A cross-sectional study was performed in Flores, Indonesia, an area highly endemic for soil-transmitted helminths (STH). Stool samples from 675 participants aged 18-80 years were collected and screened for Trichuris trichiura by microscopy and for Ascaris lumbricoides, Necator americanus, Ancylostoma duodenale, and Strongyloides stercoralis by qPCR. We collected data on body mass index (BMI), waist to hip ratio (WHR), blood pressure, fasting blood glucose (FBG), lipid, high sensitive C-reactive protein (hs-CRP), total immunoglobulin-E (TIgE) and Escherichia coli lipopolysaccharide stimulated cytokines (tumor necrosis factor and interleukin-10). In a subset of 301 elderly adults (≥40 years of age) carotid intima media thickness (cIMT) was measured. RESULTS: Participants with any STH infection had lower BMI (kg/m2) (mean difference -0.66, 95%CI [-1.26, -0.06]), WHR (-0.01, [-0.02, -0.00]), total cholesterol (mmol/L) (-0.22, [-0.43, -0.01]) and LDL-cholesterol (mmol/L) (-0.20, [-0.39, -0.00]) than uninfected participants. After additional adjustment for BMI the association between helminth infection and total cholesterol (mean difference -0.17, 95%CI [-0.37, 0.03]) as well as LDL-cholesterol (-0.15, [-0.33, 0.04]) was less pronounced. BMI, WHR, and total cholesterol were negatively associated with number species of helminth co-infections. Participants with high TIgE, an indicator of exposure to helminths, had lower FBG, TC, and HDL. The association between TIgE and TC and HDL remained significant after adjustment with BMI. No clear association was found between STH infection or TIgE and mean cIMT. CONCLUSIONS: This cross-sectional study presents evidence that helminth infections were negatively associated with risk factors for cardiovascular disease, an association at least partially mediated by an effect on BMI. The significance of this finding needs to be determined.

Fluke (Spirorchiidae) infections in sea turtles stranded on Taiwan: prevalence and pathology.

The prevalence of spirorchiid fluke infections of marine turtles is high and may cause the death of the hosts throughout their ranges. Virtually nothing has been reported regarding the infective status of sea turtles stranded on Taiwan. Between 2007 and 2010, 30 green turtles (Chelonia mydas) and 2 loggerhead turtles ( Caretta caretta ), stranded and dead, were examined for spirorchiid flukes and their eggs. Twenty-four of the green turtles were juveniles, and the stranded loggerhead turtles were subadults. Adult spirorchiid flukes were found in 13 green turtles but not in the loggerheads. Four species of flukes were identified, namely, Leardius learedi , Hapalotrema postorchis , H. mehrai , and Carettacola hawaiiensis . The main infection sites were the major arteries and heart. Seventy percent of the green turtles harbored spirorchiid eggs, but no eggs were found in loggerheads. The largest eggs with bipolar spines, type I eggs, were found in every case. Although more than half of the stranded turtles were infected, parasite infections were not the main cause of death in the green turtles. Fishery by-catch is probably responsible for the mortality of these stranded turtles.

[Autoimmune and inflammatory mechanisms of atherosclerosis development].

This paper contains the results of researches from the N.N.Anichkov laboratory of atherogenesis, the analysis of initial stages of,atherosclerosis made from the position of immune inflammation in the arterial wall. The leading role of mLDL, which are the main cholesterol carrier, in the development of immune inflammation in situ is shown.