Meritor (Brazil)

Pulmonary hypertension (PH) is characterized by extensive pulmonary vascular remodeling, leading to right ventricle (RV) hypertrophy and dysfunction. Since Rho kinases (ROCK) play a key role in smooth muscle proliferation and cardiomyocyte hypertrophy, this work evaluated the effects of ROCK inhibition by LASSBio-2020 and LASSBio-2065 on monocrotaline (MCT)-induced PH. After single injection of MCT (60 mg/kg i.p.), male Wistar rats were randomly divided in groups and treated with vehicle, LASSBio-2020 or LASSBio-2065 (60 μmol/kg/day, i.p.). Table 1 shows summarized data. After 14 days, ROCK inhibitors reduced pulmonary vascular resistance, indicated by the ratio of pulmonary acceleration time and ejection time (PAT/TET; p< 0.05) and medial wall thickness of distal pulmonary arterioles (p< 0.05). LASSBio-2020 and LASSBio-2065 also reduced Fulton index of RV hypertrophy (p< 0.05) and RV afterload, as shown by recovery of RV cardiac output (p< 0.05) and arterial elastance (p< 0.05). ROCK inhibitors improved diastolic function since both compounds reduced RV end-diastolic pressures (RVEDP) and Tau, measured through catheterization. Therefore, ROCK inhibition by LASSBio-2020 and LASSBio-2065 reverted functional and morphological alterations in PH rats and may represent a useful alternative for management of PH-associated RV dysfunction.

The aim of this work is to evaluate the applicability of the Wheeler and Willenborg models to predicting fatigue crack growth retardation in a flash welded structural steel subjected to a single overload during constant amplitude (CA) fatigue crack propagation test. Compact tension specimens, in different microstructural conditions, were subjected to a single overload at a given crack length during CA fatigue loading and crack growth rate da/dN vs. the stress intensity factor range deltaK was monitored, evidencing the retardation in crack propagation over an interval of crack length. The size of the delay zone as well as the number of the delay cycles were predicted by both the Wheeler and Willenborg models and then compared with the experimental data. Finally, the results are presented and discussed focusing on the comparison between the predictions made by the two models in the light of the experimental data.