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nov. is proposed. The type strain is SB3404T (= KCTC 49371T = JCM 34018T).Methyl mercury (MeHg) is an organic highly toxic compound that is transported efficiently via the human placenta. Our previous data suggest that MeHg is taken up into placental cells by amino acid transporters while mercury export from placental cells mainly involves ATP binding cassette (ABC) transporters. We hypothesized that the ABC transporter multidrug resistance-associated protein (MRP)1 (ABCC1) plays an essential role in mercury export from the human placenta. Transwell transport studies with MRP1-overexpressing Madin-Darby Canine Kidney (MDCK)II cells confirmed the function of MRP1 in polarized mercury efflux. Consistent with this, siRNA-mediated MRP1 gene knockdown in the human placental cell line HTR-8/SVneo resulted in intracellular mercury accumulation, which was associated with reduced cell viability, accompanied by increased cytotoxicity, apoptosis, and oxidative stress as determined via the glutathione (GSH) status. In addition, the many sources claiming different localization of MRP1 in the placenta required a re-evaluation of its localization in placental tissue sections by immunofluorescence microscopy using an MRP1-specific antibody that was validated in-house. Taken together, our results show that (1) MRP1 preferentially mediates apical-to-basolateral mercury transport in epithelial cells, (2) MRP1 regulates the GSH status of placental cells, (3) MRP1 function has a decisive influence on the viability of placental cells exposed to low MeHg concentrations, and (4) the in situ localization of MRP1 corresponds to mercury transport from maternal circulation to the placenta and fetus. We conclude that MRP1 protects placental cells from MeHg-induced oxidative stress by exporting the toxic metal and by maintaining the placental cells’ GSH status in equilibrium.Tween (polysorbate) 20 and 80 are surfactants used for the development of parenteral protein drugs, due to their beneficial safety profile and stabilisation properties. To elucidate the mechanism by which Tween 20 and 80 stabilise proteins in aqueous solutions, either by a “direct” protein to surfactant interaction and/or by an interaction with the protein film at the air-water interface, we used spectroscopic (Infrared Reflection Absorption Spectroscopy, IRRAS) and microscopic techniques (Brewster Angle Microscopy, BAM) in combination with surface pressure measurements. To this end, the impact of both types of Tweens with regard to the displacement of the protein from the air-water interface was studied. As a model protein, human serum albumin (HSA) was used. The results for the displacement of the adsorbed HSA films by Tweens 20 and 80 can partially be understood on the basis of an orogenic displacement mechanism, which depends on the critical surface pressure of the adsorbed protein film. With increasing concentration of Tween in the sub-phase, BAM images showed the formation of different domain morphologies. IRRA-spectra supported the finding that at high protein concentration in the sub-phase, the protein film could not be completely displaced by the surfactants. BV-6 mw Comparing the impact of both surfactants, we found that Tween 20 adsorbed faster to the protein film than Tween 80. The adsorption kinetics of both Tweens and the speed of protein displacement increased with rising surfactant concentration. Tween 80 reached significant lower surface pressures than Tween 20, which led to an incomplete displacement of the observed HSA film.
The evidence regarding the effect of exercise, specifically Modified Pilates (MP), on pelvic floor muscles (PFMs) is limited. We report our pilot study using the MAPLe® device to assess the effect of MP type exercises on PFM electomyographic (EMG) activity and whether PFM contraction could be performed during specific MP exercises.
The MAPLe® device was used to measure EMG activity of PFMs in healthy volunteers in different MP positions. Positions were divided into ‘neutral’, ‘core’ and ‘plank’ and EMG readings were taken at rest, during Valsalva and during active contraction.
Twenty volunteers were recruited. The median age was 35 (IQR 27-39.5)years. Higher EMG readings were seen in ‘core’ and ‘plank’ positions at rest. No position inhibited a conscious contraction and positions which engaged core muscles provoked an augmented contraction.
This is the first study to show that when MP positions are held for short periods of time, in asymptomatic women, the changes in PFM EMG are higher. This suggests that a stronger muscle contraction can be achieved when the core is co-contracted. Higher EMG readings were seen during ‘core’ and ‘plank’ positions; despite this, further activation with a conscious PFM contraction was still achievable.
This is the first study to show that when MP positions are held for short periods of time, in asymptomatic women, the changes in PFM EMG are higher. This suggests that a stronger muscle contraction can be achieved when the core is co-contracted. Higher EMG readings were seen during ‘core’ and ‘plank’ positions; despite this, further activation with a conscious PFM contraction was still achievable.
There are well-established associations between parental/peer relationships and adolescent substance use, but few longitudinal studies have examined whether adolescents change their substance use in response to changes in their parents’ behavior or peer networks. We employ a within-person change approach to address two key questions Are changes in parenting and peer factors associated with changes in adolescent marijuana and alcohol use? Are there sensitive periods when changes in parenting and peer factors are more strongly associated with changes in adolescent marijuana and alcohol use?
We analyzed longitudinal data collected annually on 503 boys, ages 13-19, recruited from Pittsburgh public schools. Questionnaires regarding parental supervision, negative parenting practices, parental stress, physical punishment, peer delinquency, and peer drug use were administered to adolescents and their caretakers. Alcohol and marijuana use were assessed by a substance use scale adapted from the National Youth Survey.