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Twenty-eight children developed chickenpox at a day care center in New Hampshire even though many had received the chickenpox vaccine. The boy who started the outbreak had also been vaccinated. However, many had been vaccinated three years before the outbreak, including the boy who started it. This outbreak shows that chickenpox occurring in vaccinated children can be just as infectious as chickenpox in unvaccinated children.

The time-resolved parallel artificial membrane permeability assay with fluorescence detection and comprehensive computer simulations are used to study the passive permeation of three aromatic dipeptides--N-acetyl-phenylalanineamide (NAFA), N-acetyltyrosineamide (NAYA), and N-acetyltryptophanamide (NATA) through a 1,2-dioleoyl-sn-glycero-3-phospocholine (DOPC) lipid bilayer. Measured permeation times and permeability coefficients showfastest translocation forNAFA, slowest for NAYA, and intermediate for NATA under physiological temperature and pH. Computationally, we perform umbrella sampling simulations to model the structure, dynamics, and interactions of the peptides as a function of z, the distance from lipid bilayer. The calculated profiles of the potential of mean force show two strong effects--preferential binding of each of the three peptides to the lipid interface and large free energy barriers in the membrane center. We use several approaches to calculate the position-dependent translational diffusion coefficients D(z), including one based on numerical solution the Smoluchowski equation. Surprisingly, computed D(z) values change very little with reaction coordinate and are also quite similar for the three peptides studied. In contrast, calculated values of sidechain rotational correlation times τrot(z) show extremely large changes with peptide membrane insertion--values become 100 times larger in the headgroup region and 10 times larger at interface and in membrane center, relative to solution. The peptides' conformational freedom becomes systematically more restricted as they enter the membrane, sampling α and β and C7eq basins in solution, α and C7eq at the interface, and C7eq only in the center. Residualwaters of solvation remain around the peptides even in the membrane center. Overall, our study provides an improved microscopic understanding of passive peptide permeation through membranes, especially on the sensitivity of rotational diffusion to position relative to the bilayer. [ABSTRACT FROM AUTHOR]

Computer simulations of passive membrane permeation provide important microscopic insights into the molecular mechanism of this important biological process that are complementary to experimental data. Our review focuses on the main approaches for calculating the free energy, or potential of mean force, for permeation of small molecules through lipid bilayers. The theoretical background for most currently used methods for potential of mean force calculation is described, including particle insertion, thermodynamic integration, umbrella sampling, metadynamics, adaptive biasing force and milestoning. A brief comparison of strengths and weaknesses of the competing approaches is presented. This is followed by a survey of results obtained by the different methods, with special attention to describing the mechanistic insights generated by modelling and illustrating capabilities of the different techniques. We conclude with a discussion of recent advances and future directions in modelling membrane permeation, including latest methodological enhancements, consideration of multiple slow variables and memory effects. [ABSTRACT FROM AUTHOR]

The adsorption of CO and CO2 on Pt supported on ZrO2 and Ce/La-promoted ZrO2 was studied using DRIFTS. The presence of both La and Ce resulted in a decrease in the adsorption of CO at room temperature after reduction at 350 °C. The reduction in the CO adsorption is ascribed to an increase in the support reducibility when La and Ce are both present. Reduction at 350 °C leads to the formation of oxygen defects in the dual promoted support which have been probed using DRIFTS to monitor CO2 dissociation. Hydrogen assisted dissociation is demonstrated on the ZrO2, CeZrO2, and LaZrO2 supports. In the absence of hydrogen, the presence of oxygen vacancies is shown to be necessary for CO2 dissociation. [ABSTRACT FROM AUTHOR]

Current research has demonstrated that nonopioid multimodal analgesia decreases perioperative opioid consumption, postoperative nausea and vomiting (PONV), and pain scores. However, no research has been conducted to examine the patient outcomes of Merit-based Incentive Payment System (MIPS) 477. This study evaluates those outcomes following implementation of MIPS 477. The medical records of 400 adult patients who underwent elective and urgent laparoscopic gynecological procedures at a facility in the Mid- Atlantic region were reviewed. Data collection included patient characteristics, analgesics administered, pain scores at postanesthesia care unit (PACU) arrival and discharge, and antiemetic administration in PACU. This study's primary outcomes were postoperative pain scores, total intraoperative and postoperative opioid consumption, and PONV. Twenty-nine patients (7.8%) met the criteria as a control group, and 341 patients (92.2%) met the criteria as a treatment group. Pain scores were higher upon PACU arrival among the control group (P = .001). The total intraoperative morphine milligram equivalents (MMEs) administered was less among the treatment group (P = .04). The treatment group had reduced total intraoperative MMEs and pain scores at PACU arrival. However, there was no statistical significance in PACU discharge pain score, total PACU MMEs, and PONV in both groups. [ABSTRACT FROM AUTHOR]

Using a wearable electromyography (EMG) and an accelerometer sensor, classification of subject activity state ( i.e ., walking, sitting, standing, or ankle circles) enables detection of prolonged "negative" activity states in which the calf muscles do not facilitate blood flow return via the deep veins of the leg. By employing machine learning classification on a multi-sensor wearable device, we are able to classify human subject state between "positive" and "negative" activities, and among each activity state, with greater than 95% accuracy. Some negative activity states cannot be accurately discriminated due to their similar presentation from an accelerometer ( i.e ., standing vs . sitting); however, it is desirable to separate these states to better inform the risk of developing a Deep Vein Thrombosis (DVT). Augmentation with a wearable EMG sensor improves separability of these activities by 30%.