Mechanism-Inspired Synthesis of Poly(alkyl malonates) via Alternating Copolymerization of Epoxides and Meldrum's Acid Derivatives.

Direct incorporation of malonate units into polymer backbones is a synthetic challenge. Herein, we report the alternating and controlled anionic copolymerization of epoxides and Meldrum's acid (MA) derivatives to access poly(alkyl malonates) using (-bis(salicylidene)phenylenediamine)AlCl and a tris(dialkylamino)cyclopropenium chloride cocatalyst. This unique copolymerization yields a malonate-containing repeat unit while releasing a small molecule upon MA-derivative ring-opening.

Mechanism of Alternating Poly(lactic--glycolic acid) Formation by Polymerization of ()- and ()-3-Methyl Glycolide Using an Enantiopure Aluminum Complex.

The mechanism(s) of alternating PLGA synthesis by ring-opening polymerization of ()- and ()-3-methyl glycolide promoted by enantiopure aluminum complexes have been rationalized by density functional theory (DFT) calculations. The high regioselectivity of the ()-MeG polymerization is obtained by repetitive ring opening at the glycolyl site by the ()-catalyst whereas a lower regioselectivity is predicted by the ROP of ()-MeG. The behavior of the two monomers is rationalized by unveiling the active site fluxionality of the enantiopure catalyst, identifying the rate-limiting steps that encode a preference at the glycolyl site versus the lactyl site, and revealing selection of the opposite monomer enantioface.

Community paramedic hospital reduction and mitigation program: study protocol for a randomized pragmatic clinical trial.

Background: New patient-centered models of care are needed to individualize care and reduce high-cost care, including emergency department (ED) visits and hospitalizations for low- and intermediate-acuity conditions that could be managed outside the hospital setting. Community paramedics (CPs) have advanced training in low- and high-acuity care and are equipped to manage a wide range of health conditions, deliver patient education, and address social determinants of health in the home setting. The objective of this trial is to evaluate the effectiveness and implementation of the Care Anywhere with Community Paramedics (CACP) program with respect to shortening and preventing acute care utilization.

ProDOT-Assisted Isomerically Pure Indophenines.

Reactions between 3,4-propylenedioxythiophenes (ProDOTs) and -alkyl isatins under ambient conditions result in isomerically pure indophenine materials as confirmed by TLC and H NMR analysis. The resulting low band gap materials exhibit favorable inter- and intramolecular interactions, high thermal stabilities, low energy electronic transitions, and amphoteric redox behavior.

Art, clinical moral perception, and the moral psychology of healthcare professionalism.

This essay describes an example of how we-one professor of the elective course Art, Medicine, and Clinical Moral Perception at Creighton University School of Medicine, one Director of Adult Programs at the Joslyn Museum of Art in Omaha, Nebraska, and fourth year medical students-practice perception skills using art objects. This essay presents one example of the journal assignments to which students respond in written narratives about their own perception habits. We also share questions any health professions educator can use to guide students' study of their habits of perception using art objects.

Cell proliferation and epidermal growth factor signaling in non-small cell lung adenocarcinoma cell lines are dependent on Rin1.

Rin1 is a Rab5 guanine nucleotide exchange factor that plays an important role in Ras-activated endocytosis and growth factor receptor trafficking in fibroblasts. In this study, we show that Rin1 is expressed at high levels in a large number of non-small cell lung adenocarcinoma cell lines, including Hop62, H650, HCC4006, HCC827, EKVX, HCC2935, and A549. Rin1 depletion from A549 cells resulted in a decrease in cell proliferation that was correlated to a decrease in epidermal growth factor receptor (EGFR) signaling.

Demonstrating sub-nm closed loop MEMS flattening.

Ground based high-contrast imaging (e.g. extrasolar giant planet detection) has demanding wavefront control requirements two orders of magnitude more precise than standard adaptive optics systems.

Effect of wavefront error on 10(-7) contrast measurements.

Received October 11, 2005; accepted November 10, 2005; posted December 2, 2005 (Doc. ID 65234) We have measured a contrast of 6.5 x 10(-8) from 10 to 25 lambda/D in visible light on the Extreme Adaptive Optics testbed, using a shaped pupil for diffraction suppression.

Experimental demonstration of phase correction with a 32 x 32 microelectromechanical systems mirror and a spatially filtered wavefront sensor.

A 32 x 32 microelectromechanical systems deformable mirror is controlled in closed loop with a spatially filtered Shack-Hartmann wavefront sensor and a Fourier-transform wavefront reconstruction algorithm. A phase plate based on atmospheric turbulence statistics is used to generate a 1 microm peak-valley static phase aberration. Far-field images and direct phase measurements of the residual are used to compare performance with and without the spatial filter.

Peroxidase activity within circulating neutrophils correlates with pulmonary phenotype in cystic fibrosis.

Excess neutrophils are present in the airways of patients with cystic fibrosis (CF). Myeloperoxidase (MPO) activity of acid extracts of sputum is directly correlated with airflow obstruction in CF patients. We hypothesized that the sputum MPO was derived from the MPO of neutrophils that entered the airways from the circulation.

Evidence of nanobacterial-like structures in calcified human arteries and cardiac valves.

Mechanisms mediating vascular calcification remain incompletely understood. Nanometer scale objects hypothesized to be a type of bacteria (nanobacteria) are associated with calcified geological specimens, human kidney stones, and psammona bodies in ovarian cancer. Experiments were designed to evaluate human vascular tissue for the presence of similar nanometer-scale objects.

The use of a positive procedure to increase engagement on-task and decrease challenging behavior.

The exhibition of stereotypic and self-injurious behavior (SIB) combined with a lack of work engagement makes it very difficult to place a person with severe disabilities in an integrated work environment. The purpose of this research was to examine use of a positive procedure to increase engagement on-task and reduce self-injurious slapping and stereotypic clothes manipulation by a 46-year-old man with severe disabilities. A single-subject research design was used to examine the effects of the combined DRA-DRO (differential reinforcement of alternative behavior-differential reinforcement of other behavior) procedure in fostering more appropriate behavior.

Effect of puberty on coronary arteries from female pigs.

Vascular function changes following loss of ovarian hormones in women at menopause and in experimental animals following surgical ovariectomy. Little is known about changes in vascular function during hormonal transition from sexual immaturity (juvenile) to sexual maturity. Therefore, experiments were designed to determine effects of natural puberty on vascular function in female pigs.

Endothelium-dependent responses in coronary arteries are changed with puberty in male pigs.

In humans, cardiovascular disease begins in young adulthood and is more prevalent in males than females. However, little is known about vascular function during transition to adulthood in males. The aim of this study was to define changes in production of endothelium-derived nitric oxide (NO) and coronary arterial responses during puberty.

Endothelial function in pigs transgenic for human complement regulating factor.

Background: Expression of human complement regulating factor (hCRF) in porcine organs prevents hyperacute rejection of these organs after xenotransplantation to nonhuman primates. Experiments were designed to characterize endothelial and smooth muscle function of arteries from pigs transgenic for hCD46.

Methods: Arterial blood from outbred pigs transgenic for hCD46 expression and nontransgenic animals of the same lineage was analyzed for angiotensin-converting enzyme (ACE), C-type natriuretic peptide (CNP), and nitric oxide.

Effect of early exposure on the integration of dental implants: Part 2--Clinical findings at 6 months postloading.

Implant exposure during initial healing after placement has been considered important in both implant integration and postloading effects. This study evaluated the effect of early implant exposure on the clinical findings prerestoration and 6 months postrestoration. Forty-eight implants (24 CPTi and 24 Ti-13-13) were placed in maxillary and mandibular posterior sites in six baboons.

Effect of unintentional exposure of 2-stage implants upon subsequent osseointegration: histologic findings 6 months postloading.

The purpose of this study was to evaluate the effect of early spontaneous exposure of 2-stage implants upon subsequent histologic bone contact following occlusal loading. As part of a study comparing 2 types of metallic threaded implants, 48 implants (24 CPTi and 24 Ti-13Nb-13Zr) were placed in maxillary and mandibular posterior sites in 6 baboons. Implant exposure was evaluated at time of placement and at each weekly visit for the first 3 weeks, then at 1, 2, and 3 months, and also at 6 months for the maxilla.

Effect of early exposure on the integration of dental implants in the baboon: Part 1--Clinical findings at uncovering.

There has been increased discussion on the advantages of a one- versus a two-stage surgical approach in the placement of dental endosseous implants. This study evaluated the influence of early implant exposure on crestal bone height adjacent to the implant surface and Periotest values at uncovering in the baboon. Forty-eight implants (24 commercially pure titanium, 24 titanium alloy) were placed in maxillary and mandibular posterior sites in 6 baboons.

Treatment with endothelin-receptor antagonists increases NOS activity in hypercholesterolemia.

In experimental hypercholesterolemia, endothelium-dependent relaxations decrease, as does endothelial immunoreactivity for nitric oxide (NO) synthase (NOS; eNOS) in coronary arteries. Systemic levels of NO also decrease with concomitant elevations in systemic circulating levels of endothelin (ET)-1. Chronic treatment of hypercholesterolemic pigs with ET-receptor antagonists increases circulating NO and improves endothelium-dependent relaxations.

Adventitial versus intimal liposome-mediated ex vivo transfection of canine saphenous vein grafts with endothelial nitric oxide synthase gene.

Purpose: Experiments were designed (1) to evaluate liposome-mediated endothelial constitutive nitric oxide synthase (ecNOS) transfection in vein grafts and (2) to compare intimal and adventitial routes of transfection.

Methods: Male mongrel dogs (N = 36) underwent bilateral femoral artery bypass grafting with the lateral saphenous vein. In each animal one vein was transfected with plasmid (pVR1012) containing the ecNOS gene, and another vein was transfected with plasmid alone (control).

Modulation of nitric-oxide synthase by nicotine.

Effects of nicotine on arterial endothelium-dependent relaxations mediated by nitric oxide are controversial. Experiments were designed to test the hypothesis that nicotine can directly alter activity of endothelial nitric-oxide synthase (eNOS). NOS from aortic endothelial cells of untreated dogs and recombinant eNOS, neuronal NOS, and inducible NOS were used for these experiments.

Time and dose effect of transdermal nicotine on endothelial function.

Nicotine patches are available as an over-the-counter medication for aid in smoking cessation. This study was designed to determine how nicotine patch therapy over time and dose ranges used in smoking cessation programs in humans affects endothelium-dependent relaxations. Dogs were treated with nicotine patches (11, 22, or 44 mg/day) for 2 and 5 wk.

A morphometric evaluation of allograft matrix combinations in the treatment of osseous defects in a baboon model.

Recent and ongoing research efforts have been made to increase the efficacy of biomaterials as structural fillers during in vivo bony reconstructions. Although the selection of the possible material choices has grown, a biomaterial that can be physically molded to the defect/void space as well as offer biomimetic tissue regeneration has yet to be made available. With the potential success of demineralized freeze-dried bone allografts (DFDBA) combined with tendonous collagen as an effective filling material, further research should help to elucidate its use.

Distribution and function of recombinant endothelial nitric oxide synthase in transplanted hearts.

Introducing recombinant genes into donor hearts may offer a therapeutic intervention that could potentially attenuate the complications of heart transplantation, including rejection, infection and accelerated atherosclerosis. In the cardiovascular system, reduced bioactivity of endothelial nitric oxide is a feature of atherosclerosis and vascular injury. Nitric oxide is an arterial vasodilator that also inhibits proliferation of vascular smooth muscle cells and platelet aggregation.