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The aim of this study was to analyze the impact of smoking on physical activity, walking capacity, and cardiovascular health in patients with symptomatic peripheral arterial disease (PAD). This cross-sectional study included 180 patients with symptomatic PAD. Patients were classified into 3 groups according to smoking history: smoker (n = 39), ex-smoker (n = 113), and never smoker (n = 28). Physical activity levels, physical function, walking capacity, and cardiovascular health parameters (clinical blood pressure, arterial stiffness, and heart rate variability) were assessed. Smoker patients presented higher sympathetic modulation to the heart (low frequency of heart rate variability: smokers, 71 ± 17 nu; ex-smokers, 53 ± 32 nu; never smokers, 49 ± 21 nu, P < .05) and sympathovagal balance (smokers: 2.44 ± 2.76, ex-smokers: 1.14 ± 1.74, never smokers: 1.04 ± 0.99, P < .05) and lower parasympathetic modulation to the heart (high frequency of heart rate variability: smokers, 29 ± 27 nu; ex-smokers, 47 ± 32 nu; never smokers, 51 ± 21 nu, P < .05) than other patients. In conclusion, nonsignificant differences were observed on physical activity levels, physical function, blood pressure, and arterial stiffness (P > .05). Smoking impairs cardiac autonomic modulation in patients with symptomatic PAD., (Copyright © 2019 Society for Vascular Nursing. Published by Elsevier Inc. All rights reserved.)

Tityus serrulatus is the scorpion specie responsible for the majority of scorpion sting accidents in Brazil. Symptoms of envenomation by Tityus serrulatus range from local pain to severe systemic reactions such as cardiac dysfunction and pulmonary edema. Thus, this study has evaluated the participation of bronchial epithelial cells in the pulmonary effects of Tityus serrulatus scorpion venom (Tsv). Human bronchial epithelial cell line BEAS-2B were utilized as a model target and were incubated with Tsv (10 or 50 μg/mL) for 1, 3, 6 and 24 h. Effects on cellular response of venom-induce cytotoxicity were examined including cell viability, cell integrity, cell morphology, apoptosis/necrosis as well as cell activation through the release of pro-inflammatory cytokines IL-1β, IL-6 and IL-8. Tsv caused a decrease in cell viability at 10 and 50 μg/mL, which was confirmed by lactate dehydrogenase (LDH) measurement. Flow cytometry analyses revealed necrosis as the main cell death pathway caused by Tsv. Furthermore, Tsv induced the release of IL-1β, IL-6 and IL-8. Altogether, these results demonstrate that Tsv induces cytotoxic effects on bronchial epithelial cells, involving necrosis and release of pro-inflammatory cytokines, suggesting that bronchial epithelial cells may play a role in the pulmonary injury caused by Tsv., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Xylopia langsdorfiana A. St.-Hil. &Tul. (Annonaceae) is popularly known in the northeast of Brazil as 'pimenteira da terra', and an essential oil (XL-OE) was extracted from its leaves. Since Xylopia species are cited in folk medicine and diterpenes from X. langsdorfiana have spasmolytic activity, this study aimed to investigate a possible spasmolytic action of XL-OE on smooth muscle models. XL-OE (243 and 729 μg/mL) showed low pharmacologic efficacy on guinea pig trachea and rat aorta and uterus. However, in guinea pig ileum, XL-OE (27-729 μg/mL) inhibited carbachol or histamine-induced phasic contractions (1 μM) in a significant and concentration-dependent manner. In addition, XL-OE (81 μg/mL) reduced fluorescence intensity in ileal myocytes stimulated by histamine, indicating a decrease in cytosolic calcium concentration, which could explain the spasmolytic activity. Thus, XL-OE proved to be a promising natural product to be used in gastrointestinal diseases acting by modulating the cytosolic calcium concentration.

In this study we investigated the mechanism underlying the spasmolytic action of ent-7α-acetoxytrachyloban-18-oic acid (trachylobane-360) and ent-7α-hydroxytrachyloban-18-oic acid (trachylobane-318), diterpenes obtained from Xylopia langsdorfiana, on guinea pig ileum. Both compounds inhibited histamine-induced cumulative contractions (slope=3.5±0.9 and 4.4±0.7) that suggests a noncompetitive antagonism to histaminergic receptors. CaCl(2)-induced contractions were nonparallelly and concentration-dependently reduced by both diterpenes, indicating blockade of calcium influx through voltage-dependent calcium channels (Ca(v)). The Ca(v) participation was confirmed since both trachylobanes equipotently relaxed ileum pre-contracted with S-(-)-Bay K8644 (EC(50)=3.5±0.7×10-(5) and 1.1±0.2×10-(5)M) and KCl (EC(50)=5.5±0.3×10-(5) and 1.4±0.2×10-(5)M). K(+) channels participation was confirmed since diterpene-induced relaxation curves were significantly shifted to right in the presence of 5mM tetraethylammonium (TEA(+)) (EC(50)=0.5±0.04×10-(4) and 2.0±0.5×10-(5)M). ATP-sensitive K(+) channel (K(ATP)), voltage activated K(+) channels (K(V)), small conductance calcium-activated K(+) channels (SK(Ca)) or big conductance calcium-activated K(+) channels (BK(Ca)) did not seem to participate of trachylobane-360 spasmolytic action. However trachylobane-318 modulated positively K(ATP), K(V) and SK(Ca) (EC(50)=1.1±0.3×10-(5), 0.7±0.2×10-(5) and 0.7±0.2×10-(5)M), but not BK(Ca). A fluorescence analysis technique confirmed the decrease of cytosolic calcium concentration ([Ca(2+)](c)) induced by both trachylobanes in ileal myocytes. In conclusion, trachylobane-360 and trachylobane-318 induced spasmolytic activity by K(+) channel positive modulation and Ca(2+) channel blockade, which results in [Ca(2+)](c) reduction at cellular level leading to smooth muscle relaxation., (Copyright © 2011. Published by Elsevier B.V.)

We have previously shown that monoclonal antibodies directed to the 90 kDa glycoprotein and the 35/50 kDa glycoconjugate, present on the surface of Trypanosoma cruzi metacyclic trypomastigotes, inhibited host cell invasion. Here we investigated whether these molecules could be the ligands for the target cell receptor. Binding assays were performed by incubating Vero cells with sonicated parasite extract. Detection of bound parasite components was carried out by using monoclonal antibodies (MoAbs) IG7 and 10D8, which recognize the 90 kDa and the 35/50 kDa antigens respectively. These experiments revealed that the 35/50 kDa glycoconjugate of metacyclic forms, but not the 1G7-reactive antigen, binds to Vero cells. The purified 35/50 kDa antigen bound to Vero cells and inhibited the entry of metacyclic forms in a dose-dependent manner. Although to a lesser extent, an immunologically related 35/50 kDa antigen of non-infective epimastigotes also bound to Vero cells but it was unable to inhibit parasite penetration at a concentration (100 micrograms/ml) in which metacyclic antigen exhibited more than 60% inhibition. All these data suggest that the metacyclic 35/50 kDa surface glycoconjugate is a ligand to the host cell in the process of T. cruzi invasion.