Organocatalytic ring opening polymerization of trimethylene carbonate.

A variety of organocatalysts has been surveyed in the ring opening polymerization of trimethylene carbonate. Excellent control was found for several of these catalysts yielding well-defined polycarbonates with molecular weights up to 50,000 g mol(-1), polydispersities below 1.08, and high end-group fidelity.

Starlike dendrimers in solutions: structural properties and internal dynamics.

We measured the shape and the internal dynamics of starlike dendrimers under good solvent conditions with small-angle neutron scattering and neutron spin-echo (NSE) spectroscopy, respectively. Architectural parameters such as the spacer length and generation were varied in a systematic manner. Structural changes occurring in the dendrimers as a function of these parameters are discussed, i.

Cephalosporins for uncomplicated skin and skin structure infections in emerging community-acquired MRSA.

The treatment of community uncomplicated skin and skin structure infections (uSSSIs) mandates that treatment should be based on careful consideration of infection attributes and patient characteristics, particularly in this era of community-acquired MRSA as an emerging pathogen. However, as most uSSSIs in the community continue to be caused by methicillin-susceptible Staphylococcus aureus or streptococci, effective treatment against these key pathogens should aim to achieve prompt eradication, along with minimal risk of antimicrobial resistance. Cephalosporins are an effective broad-spectrum empirical treatment for uSSSIs, with considerable activity against methicillin-susceptible S.

Organocatalytic living ring-opening polymerization of cyclic carbosiloxanes.

[reaction: see text] An organocatalytic route to narrowly dispersed poly(carbosiloxanes) of predictable molecular weight and end group fidelity is described. N-Heterocyclic carbenes (NHC) and 1,5,7-triazabicyclo[4.4.

Synthesis of well-defined hydrogel networks using click chemistry.

New PEG-based hydrogel materials have been synthesized by Click chemistry and shown to result in well-defined networks having significantly improved mechanical properties; the selectivity of the azide/acetylene coupling reaction also allows for the incorporation of various additives and functional groups leading to chemical tailoring of the hydrogels.

Stereoselective polymerization of rac- and meso-lactide catalyzed by sterically encumbered N-heterocyclic carbenes.

New sterically encumbered N-heterocyclic carbene catalysts were synthesized and used to polymerize rac-lactide to give highly isotactic polylactide or meso-lactide to give heterotactic polylactide.

An acute care surgery model improves outcomes in patients with appendicitis.

Objective: To compare outcomes of appendectomy in an Acute Care Surgery (ACS) model to that of a traditional home-call attending surgeon model.

Summary Background Data: Acute care surgery (ACS, a combination of trauma surgery, emergency surgery, and surgical critical care) has been proposed as a practice model for the future of general surgery. To date, there are few data regarding outcomes of surgical emergencies in the ACS model.

Monolayered organosilicate toroids and related structures: A phase diagram for templating from block copolymers.

Here we report the controlled generation of micelle-templated organosilicate nanostructures resulting from self-assembly of a block copolymer/organosilicate mixture followed by organosilicate vitrification and copolymer thermolysis. Variation of solution condition and the copolymer/organosilicate mixture composition generates widely different film morphologies ranging from toroids to linear features to contiguous nanoporous monolayers. The use of reactive organosilicates for block copolymer templation generates functional inorganic nanostructures with thermal and mechanical stability.

Targeted deletion of Gpbar1 protects mice from cholesterol gallstone formation.

The Gpbar1 [G-protein-coupled BA (bile acid) receptor 1] is a recently identified cell-surface receptor that can bind and is activated by BAs, but its physiological role is unclear. Using targeted deletion of the Gpbar1 gene in mice, we show that the gene plays a critical role in the maintenance of bile lipid homoeostasis. Mice lacking Gpbar1 expression were viable, developed normally and did not show significant difference in the levels of cholesterol, BAs or any other bile constituents.

Triazabicyclodecene: a simple bifunctional organocatalyst for acyl transfer and ring-opening polymerization of cyclic esters.

1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) is an effective organocatalyst for acyl transfer as well as the ring-opening polymerization of cyclic esters.

Acellular pertussis vaccine booster combined with diphtheria and tetanus toxoids for adolescents.

Background: The incidence of pertussis is increasing, especially in adolescents, attributed in part to waning of immunity after childhood immunization. Recently licensed in the United States for use in adolescents, acellular pertussis vaccines will provide an immunogenic and safe option for booster immunization against pertussis.

Methods: This prospective, randomized, observer-blinded, multicenter, comparative study evaluated the safety and immunogenicity of a vaccine formulated with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis antigens (Tdap) compared with tetanus and diphtheria toxoids vaccine (Td) for booster immunization in adolescents.

The lived experience of pregnancy while carrying a child with a known, nonlethal congenital abnormality.

Objective: To gain an understanding of the experience of pregnancy while carrying a child with a known, nonlethal congenital abnormality.

Design: Phenomenological study.

Setting: The participants were interviewed in their own homes, a quiet clinic room, or another location comfortable for them.

Oriented mesoporous organosilicate thin films.

Coassemblies of block copolymers and inorganic precursors offer a path to ordered inorganic nanostructures. In thin films, these materials combined with domain alignment provide highly robust nanoscopic templates. We report a simple path to control the morphology, scaling, and orientation of ordered mesopores in organosilicate thin films through the coassembly of a diblock copolymer, poly(styrene-b-ethylene oxide) (PS-b-PEO), and an oligomeric organosilicate precursor that is selectively miscible with PEO.

Thiourea-based bifunctional organocatalysis: supramolecular recognition for living polymerization.

A versatile, metal-free, organocatalytic approach to the living ring-opening polymerization of lactide using a bifunctional thiourea-tertiary amine catalyst is described. Mild and highly selective polymerization conditions produced poly(lactides) with predictable molecular weights and extremely narrow polydispersities ( approximately 1.05), characteristic of a living polymerization.

Subtelomere FISH analysis of 11 688 cases: an evaluation of the frequency and pattern of subtelomere rearrangements in individuals with developmental disabilities.

Background: Subtelomere fluorescence in situ hybridisation (FISH) analysis has increasingly been used as an adjunct to routine cytogenetic testing in order to detect small rearrangements. Previous reports have estimated an overall abnormality rate of 6%, with a range of 2-29% because of different inclusion criteria.

Methods: This study presents data compiled from 11 688 cases referred for subtelomere FISH testing in three clinical cytogenetic laboratories.

Trace level perchlorate analysis by ion chromatography-mass spectrometry.

Perchlorate is commonly used as an oxidant in solid fuel propellant for rockets and missiles. Recently perchlorate contamination was found in many aquifers associated with Colorado River and other sites. Perchlorate was also found at elevated level in crops that use contaminated water for irrigation.

The evolving role of interventional radiology in trauma care.

Background: Although the traditional role of radiology in trauma care has been diagnostic, therapeutic interventional radiology (IR) techniques have now become essential in the management of many injuries. We hypothesized that IR has evolved at our institution over the last decade from a largely diagnostic to a more therapeutic role in the care of the injured patient.

Methods: Demographic information, computed tomographic scans of the chest and abdomen, and angiographic procedures (APs) performed within 48 hours of admission were reviewed in all patients evaluated at a Level I trauma center for the periods 1993 to 1995 and 2000 to 2002.

Discovery of an MIT-like atracotoxin family: spider venom peptides that share sequence homology but not pharmacological properties with AVIT family proteins.

This project identified a novel family of six 66-68 residue peptides from the venom of two Australian funnel-web spiders, Hadronyche sp. 20 and H. infensa: Orchid Beach (Hexathelidae: Atracinae), that appear to undergo N- and/or C-terminal post-translational modifications and conform to an ancestral protein fold.

Single-component catalyst/initiators for the organocatalytic ring-opening polymerization of lactide.

The synthesis and characterization of a series of primary and secondary alcohol adducts of 1,3-dimesitylimidazolin-2-ylidene is described. These adducts are stable as solids at room temperature, but readily release alcohol and the free carbene in solution. These alcohol adducts function as excellent single-component catalyst/initiators for the ring-opening polymerization of lactide under mild conditions, providing polymers with controlled molecular weights and narrow polydispersities.

Transgenic overexpression of neuromedin U promotes leanness and hypophagia in mice.

Recent work has shown that neuromedin U (NmU), a peptide initially identified as a smooth muscle contractor, may play a role in regulating food intake and energy homeostasis. To further evaluate this putative function, we measured food intake, body weight, energy expenditure and glucose homeostasis in transgenic mice that ubiquitously overexpress murine proNmU. NmU transgenic mice were lighter and had less somatic and liver fat, were hypophagic, and had improved insulin sensitivity as judged by an intraperitoneal insulin tolerance test.