Search results for " STRESS"

Intravascular pillars and pruning in the extraembryonic vessels of chick embryos.

2010

To investigate the local mechanical forces associated with intravascular pillars and vessel pruning, we studied the conducting vessels in the extraembryonic circulation of the chick embryo. During the development days 13-17, intravascular pillars and blood flow parameters were identified using fluorescent vascular tracers and digital time-series video reconstructions. The geometry of selected vessels was confirmed by corrosion casting and scanning electron microscopy. Computational simulations of pruning vessels suggested that serial pillars form along pre-existing velocity streamlines; blood pressure demonstrated no obvious spatial relationship with the intravascular pillars. Modeling a Re…

Slāpekļa (II) oksīda metabolīti multiplās sklerozes slimnieku asins plazmā atkarībā no terapijas efektivitātes

2020

Multiplā skleroze (MS) ir kompleksā, neirodeģeneratīvā saslimšana ar izteikto autoimūno komponentu, ar kuru slimo ap 2,2 miljoniem vidēja vecuma cilvēku visā pasaulē. Slimībai progresējot, attīstās fiziskā un garīga nespēja, kas noved pie pacienta nāves, visbiežāk no elpceļu infekcijām, 12-25 gadu laikā pēc klīnisko simptomu atklāšanas. Mūsdienās pieejamie terapijas veidi dod iespēju palēnināt slimības progresiju, bet neļauj pilnībā to izārstēt. Kamēr nav pieejama efektīva ārstēšanas metode, liela nozīme ir diagnostikas kritēriju un laboratorijas testu izstrādei, kas ļautu noteikt slimības pazīmes pirms vai pēc minimāli izteiktas simptomātikas rašanās. Tas var dot iespēju ātrāk uzsākt uztur…

Role of peroxiredoxin 6 in the chondroprotective effects of microvesicles from human adipose tissue-derived mesenchymal stem cells

2021

Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://www.sciencedirect.com/science/article/pii/S2214031X21000656?via%3Dihub Background: Osteoarthritis (OA) is a joint disease characterized by cartilage degradation, low-grade synovitis and subchondral bone alterations. In the damaged joint, there is a progressive increase of oxidative stress leading to disruption of chondrocyte homeostasis. The modulation of oxidative stress could control the expression of inflammatory and catabolic mediators involved in OA. We have previously demonstrated that extracellular vesicles (EVs) present in the secretome of human mesenchymal stem cells from adipose tissu…

Persistence of the effects of the covid-19 lockdown on sleep: A longitudinal study

2021

The effects of the COVID-19 pandemic on sleep have been widely documented, but longitudinal evaluations during different phases of the “COVID-19 era” are needed to disentangle the specific consequences of the r145estrictive measures on sleep variables. The aim of this study was to assess the immediate effect of the lockdown’s end on sleep and sleep-related dimensions in an Italian sample, also considering the stress and depressive symptoms. We used an online survey to longitudinally collect data on sociodemographic, environmental, clinical, sleep, and sleep-related variables in two time points: during and immediately after the lockdown. The final sample included 102 participants. The large …

Perinatal Parenting Stress, Anxiety, and Depression Outcomes in First-Time Mothers and Fathers: A 3- to 6-Months Postpartum Follow-Up Study

2016

Objective: Although there is an established link between parenting stress, postnatal depression, and anxiety, no study has yet investigated this link in first-time parental couples. The specific aims of this study were 1) to investigate whether there were any differences between first-time fathers’ and mothers’ postnatal parenting stress, anxiety, and depression symptoms and to see their evolution between three and 6 months after their child’s birth; and 2) to explore how each parent’s parenting stress and anxiety levels and the anxiety levels and depressive symptoms of their partners contributed to parental postnatal depression. Method: The sample included 362 parents (181 couples; mothers…

Computational Fluid Dynamics Simulation of Hydrodynamics and Stresses in the PhEur/USP Disintegration Tester Under Fed and Fasted Fluid Characteristi…

2015

ABSTRACT: Disintegration of oral solid dosage forms is a prerequisite for drug dissolution and absorption and is to a large extent dependent on the pressures and hydrodynamic conditions in the solution that the dosage form is exposed to. In this work, the hydrodynamics in the PhEur/USP disintegration tester were investigated using computational fluid dynamics (CFD). Particle image velocimetry was used to validate the CFD predictions. The CFD simulations were performed with different Newtonian and non-Newtonian fluids, representing fasted and fed states. The results indicate that the current design and operating conditions of the disintegration test device, given by the pharmacopoeias, are n…

Effects of bupivacaine on human erythrocytes submitted to stress and evidence for an interaction between bupivacaine and flumazenil

1999

Aims To examine the effects of bupivacaine on erythrocytes submitted to an oxidative stress (AAPH) and to provide evidence for an in vitro interaction between bupivacaine and flumazenil. Methods Human erythrocytes were studied with or without AAPH in the presence of different concentrations of bupivacaine (0.15, 0.3, 0.9 and 1.8 mmol l−1 ), or flumazenil (0.16 mmol l−1 ) and with the association of flumazenil and two doses of bupivacaine (0.15 and 0.3 mmol l−1 ). Potassium efflux was measured by flame photometry at t0, and every 30 min for 2 h. Results In the absence of AAPH, extracellular potassium remained unchanged. Oxidative stress induced a significant increase in extracellular potassi…

Contribution of oxidative stress to excitotoxicity-induced deleterious iNOS in the CNS.

1999

A new class of organic nitrates: investigations on bioactivation, tolerance and cross-tolerance phenomena

2009

Background and purpose:  The chronic use of organic nitrates is limited by serious side effects including oxidative stress, nitrate tolerance and/or endothelial dysfunction. The side effects and potency of nitroglycerine depend on mitochondrial aldehyde dehydrogenase (ALDH-2). We sought to determine whether this concept can be extended to a new class of organic nitrates with amino moieties (aminoalkyl nitrates). Experimental approach:  Vasodilator potency of the organic nitrates, in vitro tolerance and in vivo tolerance (after continuous infusion for 3 days) were assessed in wild-type and ALDH-2 knockout mice by isometric tension studies. Mitochondrial oxidative stress was analysed by L-012…

Targeting Oxidative Stress as a Therapeutic Approach for Idiopathic Pulmonary Fibrosis

2022

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease characterized by an abnormal reepithelialisation, an excessive tissue remodelling and a progressive fibrosis within the alveolar wall that are not due to infection or cancer. Oxidative stress has been proposed as a key molecular process in pulmonary fibrosis development and different components of the redox system are altered in the cellular actors participating in lung fibrosis. To this respect, several activators of the antioxidant machinery and inhibitors of the oxidant species and pathways have been assayed in preclinicalin vitroandin vivomodels and in different clinical trials. This review discusses the role of …