Mcdonaldqvist4459

To this end, an extensive review of data sets bearing on MTBE and metabolite genotoxicity, cytotoxicity, and tumorigenicity was applied to reassess MTBE CP and related uncertainty in view of MOA considerations. Adopting the traditional approach that cytotoxicity-driven cancer MOAs are inoperative at very low, non-cytotoxic dose levels, it was determined that MTBE most likely does not increase cancer risk unless chronic exposures induce target-tissue toxicity, including in sensitive individuals. However, the corresponding expected (or plausible upper bound) CP for MTBE conditional on a hypothetical linear (e.g., genotoxic) MOA was estimated to be ∼2 × 10(-5) (or 0.003) per mg MTBE per kg body weight per day for adults exposed chronically over a lifetime. Based on this conservative estimate of CP, if MTBE is carcinogenic to humans, it is among the weakest 10% of chemical carcinogens evaluated by EPA.The dielectric response and electrical properties of junctions based on self-assembled monolayers (SAMs) of the form S(CH2)11X can be controlled by changing the polarizability of X (here X = H, F, Cl, Br, or I). A 1000-fold increase in the tunneling rate and a four-fold increase of the dielectric constant (ε r ) with increasing polarizability of X are found.Formation of metal rich conductive filaments and their rearrangements determine the switching characteristics in HfO2 based resistive random access memory (RRAM) devices. The initiation of a filament formation process may occur either via aggregation of pre-existing vacancies randomly distributed in the oxide or via generation of new oxygen vacancies close to the pre-existing ones. We evaluate the feasibility of vacancy aggregation processes by calculating the structures and binding energies of oxygen vacancy aggregates consisting of 2, 3 and 4 vacancies in bulk monoclinic (m)-HfO2 using density functional theory (DFT). We demonstrate that formation of neutral oxygen vacancy aggregates is accompanied by small energy gain, which depends on the size and shape of the aggregate. In the most strongly bound configurations, vacancies are unscreened by Hf cations and form voids within the crystal, with the larger aggregates having larger binding energy per vacancy (-0.11 to  -0.18 eV). The negatively charged di-vacancy was found to have similar binding energies to the neutral one, while the positively charged di-vacancy was found to be unstable. Thus aggregation process of either neutral or negatively charged oxygen vacancies is energetically feasible.

Tissue-engineered colon (TEC) might potentially replace absent or injured large intestine, but the enteric nervous system (ENS), a key component, has not been investigated. In various enteric neuropathic diseases in which the TEC is derived from aganglionic donor colon, the resulting construct might also be aganglionic, limiting tissue engineering applications in conditions such as Hirschsprung disease (HD). We hypothesized that TEC might contain a diverse population of enteric neuronal subtypes, and that aganglionic TEC can be populated by neurons and glia when supplemented with ENS progenitor cells in the form of neurospheres.

Human and murine organoid units (OU) and multicellular clusters containing epithelium and mesenchyme were isolated from both mouse and human donor tissues, including from normally innervated and aganglionic colon. The OU were seeded onto a biodegradable scaffold and implanted within a host mouse, resulting in the growth of TEC. GSK3 inhibitor Aganglionic murine and human OU were supplemented witm aganglionic colon can be populated with neurons and glia when supplemented with neurospheres. Combining tissue engineering and cellular replacement therapies represents a new strategy for treating enteric neuropathies, particularly HD.

Pulse pressure (PP) amplification expressed as the peripheral-to-central PP ratio has gained importance in the assessment of cardiovascular phenotypes and cardiovascular risk. The aim of the present study was to assess the relationship between PP amplification, large vessel parameters and peripheral blood pressure (BP) to gain insights into the amplification phenomenon.

Peripheral BP, central BP and carotid-femoral pulse wave velocity (cfPWV) were assessed using the OMRON M6, SphygmoCor and Complior devices, respectively, in 741 adults attending the hypertension outpatient clinic. Analysis of covariance, partial correlations and multiple linear regression models were performed to assess the relationship between PP amplification, peripheral BP and cfPWV.

PP amplification was inversely related to BP group. Women showed lower PP amplification than men (1.24 ± 0.18 and 1.35 ± 0.18, respectively, p < 0.001). Age, female gender and mean arterial pressure were inversely associated with PP amplification (p < 0.001), whereas heart rate and body mass index showed positive associations (p < 0.001 and p = 0.049, respectively). cfPWV was a predictor of PP amplification in men but not in women (p = 0.006 and p = 0.424, respectively).

PP amplification is related to BP the higher the BP, the lower the PP amplification. Gender, age and body composition have a significant impact on PP amplification.

PP amplification is related to BP the higher the BP, the lower the PP amplification. Gender, age and body composition have a significant impact on PP amplification.

Despite advances in therapies, disparities in outcomes have been documented for rheumatoid arthritis (RA) patients for both ethnicity and English language proficiency. The goals of these analyses were to compare differences in RA patient-reported outcomes, by both self-identification of ethnicity and English language proficiency, and to identify factors that might explain differences among groups.

Data were collected through structured telephone interviews of a longitudinal cohort with physician-diagnosed RA (n = 438); only women were included (n = 335). Three groups were defined based on self-reported ethnicity and English proficiency white/English (n = 219), Hispanic/English (n = 39), and Hispanic/Spanish (n = 77). Outcomes examined were patient-reported physical functioning, pain, and presence of moderate or severe fatigue. Multivariate regression analyses compared outcomes among groups, adjusting for sociodemographic characteristics, health and disease factors, and depression.

Hispanic/Spanish womenoutcomes may be driven less by ethnicity than by sociodemographic or psychological factors. Measurement instruments that are not culturally appropriate and equivalent may also hamper meaningful analyses of disparities.There is controversy as to how responses to colour in the human brain are organized within the visual pathways. A key issue is whether there are modular pathways that respond selectively to colour or whether there are common neural substrates for both colour and achromatic (Ach) contrast. We used functional magnetic resonance imaging (fMRI) adaptation to investigate the responses of early and extrastriate visual areas to colour and Ach contrast. High-contrast red-green (RG) and Ach sinewave rings (0.5 cycles/degree, 2 Hz) were used as both adapting stimuli and test stimuli in a block design. We found robust adaptation to RG or Ach contrast in all visual areas. Cross-adaptation between RG and Ach contrast occurred in all areas indicating the presence of integrated, colour and Ach responses. Notably, we revealed contrasting trends for the two test stimuli. For the RG test, unselective processing (robust adaptation to both RG and Ach contrast) was most evident in the early visual areas (V1 and V2), but selective responses, revealed as greater adaptation between the same stimuli than cross-adaptation between different stimuli, emerged in the ventral cortex, in V4 and VO in particular. For the Ach test, unselective responses were again most evident in early visual areas but Ach selectivity emerged in the dorsal cortex (V3a and hMT+). Our findings support a strong presence of integrated mechanisms for colour and Ach contrast across the visual hierarchy, with a progression towards selective processing in extrastriate visual areas.Two new proanthocyanidin trimers have been isolated from Cistus incanus herb; gallocatechin-(4α→6)-gallocatechin-(4α→8)-gallocatechin (compound 1) and epigallocatechin-3-O-gallate-(4ß→8)-epigallocatechin-3-O-gallate-(4ß→8)-gallocatechin (compound 2). The structures were determined on the basis of 1D- and 2D-NMR (HSQC, HMBC) of their peracetylated derivatives, MALDI-TOF-MS and by acid-catalysed degradation with phloroglucinol. A more abundant proanthocyanidin oligomer was also isolated, purified and its chemical constitution studied by (13)C-NMR and phloroglucinol degradation. The mean molecular weight of the polymer was estimated to be about 7 to 8 flavan-3-ol-units with a ratio of procyanidin  prodelphinidin units at 15, some of which are derivatised by gallic acid. Water extract and higher oligomeric proanthocyanidin fractions of C. incanus significantly inhibited TPA-induced oedema when applied topically at doses of 0.5 and 1 mg/ear in mice. Furthermore, the extracts and the pure compounds inhibited COX-1 and COX-2 activities. In addition, compound 2 exhibited an IC50 of 4.5 μM against COX-2 indicating its high selectivity towards COX-2.Occupational health and safety management systems apply audit examinations as an integral element of these systems. The examinations are used to verify whether the undertaken actions are in compliance with the accepted regulations, whether they are implemented in a suitable way and whether they are effective. One of the earliest solutions of that type applied in the mining industry in Poland involved the application of audit research based on the MERIT survey (Management Evaluation Regarding Itemized Tendencies). A mathematical model applied in the survey facilitates the determination of assessment indexes WOPi for each of the assessed problem areas, which, among other things, can be used to set up problem area rankings and to determine an aggregate (synthetic) assessment. In the paper presented here, the assessment indexes WOPi were used to calculate a development measure, and the calculation process itself was supplemented with sensitivity analysis.

To determine the effect of obesity on radiation exposure during simulated ureteroscopy.

A validated anthropomorphic adult male phantom with a body mass index (BMI) of approximately 24 kg/m(2), was positioned to simulate ureteroscopy. Padding with radiographic characteristics of human fat was placed around the phantom to create an obese model with BMI of 30 kg/m(2). Metal oxide semiconductor field effect transistor (MOSFET) dosimeters were placed at 20 organ locations in both models to measure organ dosages. A portable C-arm was used to provide fluoroscopic x-ray radiation to simulate ureteroscopy. Organ dose rates were calculated by dividing organ dose by fluoroscopy time. Effective dose rate (EDR, mSv/sec) was calculated as the sum of organ dose rates multiplied by corresponding ICRP 103 tissue weighting factors.

The mean EDR was significantly increased during left ureteroscopy in the obese model at 0.0092 ± 0.0004 mSv/sec compared with 0.0041 ± 0.0003 mSv/sec in the nonobese model (P < 0.01), as well as during right ureteroscopy at 0.