Vaginal compared with intramuscular progestogen for preventing preterm birth in high-risk pregnant women (VICTORIA study): a multicentre, open-label randomised trial and meta-analysis.

OBJECTIVE: To compare the efficacy of two types of progestogen therapy for preventing preterm birth (PTB) and to review the relevant literature. DESIGN: A multicentre, randomised, open-label, equivalence trial and a meta-analysis. SETTING: Tertiary referral hospitals in South Korea. POPULATION: Pregnant women with a history of spontaneous PTB or short cervical length (<25 mm). METHODS: Eligible women were screened and randomised at 16-22 weeks of gestation to receive either 200 mg of vaginal micronised progesterone daily (vaginal group) or an intramuscular injection of 250 mg 17α-hydroxyprogesterone caproate weekly (IM group). Stratified randomisation was carried out according to participating centres and indications for progestogen therapy. This trial was registered at ClinicalTrials.gov (NCT02304237). MAIN OUTCOME MEASURE: Preterm birth (PTB) before 37 weeks of gestation. RESULTS: A total of 266 women were randomly assigned and a total of 247 women (119 and 128 women in the vaginal and IM groups, respectively) were available for the intention-to-treat analysis. Risks of PTB before 37 weeks of gestation did not significantly differ between the two groups (22.7 versus 25.8%, P = 0.571). The difference in PTB risk between the two groups was 3.1% (95% CI -7.6 to 13.8%), which was within the equivalence margin of 15%. The meta-analysis results showed no significant differences in the risk of PTB between the vaginal and IM progestogen treatments. CONCLUSION: Compared with vaginal progesterone, treatment with intramuscular progestin might increase the risk of PTB before 37 weeks of gestation by as much as 13.8%, or reduce the risk by as much as 7.6%, in women with a history of spontaneous PTB or with short cervical length. TWEETABLE ABSTRACT: Vaginal and intramuscular progestogen showed equivalent efficacy for preventing preterm birth before 37 weeks of gestation.

The coronary CT angiography vision protocol: a prospective observational imaging cohort study in patients undergoing non-cardiac surgery.

INTRODUCTION: At present, physicians have a limited ability to predict major cardiovascular complications after non-cardiac surgery and little is known about the anatomy of coronary arteries associated with perioperative myocardial infarction. We have initiated the Coronary CT Angiography (CTA) VISION Study to (1) establish the predictive value of coronary CTA for perioperative myocardial infarction and death and (2) describe the coronary anatomy of patients that have a perioperative myocardial infarction. METHODS AND ANALYSIS: The Coronary CTA VISION Study is prospective observational study. Preoperative coronary CTA will be performed in 1000-1500 patients with a history of vascular disease or at least three cardiovascular risk factors who are undergoing major elective non-cardiac surgery. Serial troponin will be measured 6-12 h after surgery and daily for the first 3 days after surgery. Major vascular outcomes at 30 days and 1 year after surgery will be independently adjudicated. ETHICS AND DISSEMINATION: Coronary CTA results in a measurable radiation exposure that is similar to a nuclear perfusion scan (10-12 mSV). Treating physicians will be blinded to the CTA results until 30 days after surgery in order to provide the most unbiased assessment of its prognostic capabilities. The only exception will be the presence of a left main stenosis >50%. This approach is supported by best available current evidence that, excluding left main disease, prophylatic revascularisation prior to non-cardiac surgery does not improve outcomes. An external safety and monitoring committee is overseeing the study and will review outcome data at regular intervals. Publications describing the results of the study will be submitted to major peer-reviewed journals and presented at international medical conferences.

Novel F-releasing composite with improved mechanical properties.

In recent years, the authors have been developing novel fluoride-releasing dental composites containing ternary zirconium fluoride chelates. The aim of this study was to improve the physical and mechanical properties of these composites by improving the formulation of the monomers and photoinitiators. The hypothesis was that reduction of hydrophilic monomers and improvement of the photoinitiators could reduce water sorption and significantly increase the mechanical properties of the composite. The degree of conversion of the composites containing different compositions of photoinitiators was studied by Fourier transform near-infrared spectroscopy (FT-NIR). Ten experimental composites containing different compositions of ethoxylated bisphenol-A dimethacrylate (EBPADMA), 1,6-hexanediol dimethacrylate (HDDMA), triethylene glycol dimethacrylate (TEGDMA), and 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy) phenyl]-propane (BisGMA) were tested for flexural strength, viscosity, and water sorption. The experimental composite containing 20% synthesized fluoride-releasing monomer, 30% BisGMA, 30% EBPADMA, and 20% HDDMA showed significantly higher fluoride release and recharge, but physical and mechanical properties similar to those of the control composite containing 40% BisGMA, 40% EBPADMA, and 20% HDDMA.

Cost-effective monitoring for a soil vapor extraction (SVE) system: a simplified modeling and gas sensor test.

In order to establish cost-effective monitoring strategies for soil vapor extraction (SVE), a simplified model for multi-component mass transfer of a complex liquid mixture in porous media and gas sensor are proposed and experimentally evaluated. The basic task for the cost-effective monitoring of SVE is to decide how to predict the performances of venting systems in terms of the contaminant vapor removal rate and the time required to accomplish the clean-up specification. The method includes classifying of individual components of a complex mixture on the basis of gas chromatographic (GC) profile and treating each resulting group as a pseudo-single compound. BTEX components of gasoline were selected for model input and the remainders were divided into 4 groups based on their GC retention times. The model proposed in this study is capable of predicting with accuracy volatilization behaviors of gasoline components in soil and the gas sensor (FIGARO TGS 823) was tested by GC-FID to toluene and TPH-GRO(Total Petroleum Hydrocarbon-Gasoline Range Organics) gas samples. A VOC gas sensor was developed which recognizes TPH-GRO concentrations between 250 and 50 ppm. The developed gas sensor test and proposed model can be used as a valuable tool for the cost-effective monitoring for SVE systems.

Self-assembled monolayers of rigid thiols.

The preparation, structure, properties and applications of self-assembled monolayers (SAMs) of rigid 4-mercapto-biphenyls are briefly reviewed. The rigid character of the biphenyl moiety results in a molecular dipole moment that affects both the adsorption kinetics on gold surfaces, as well as the equilibrium structure of mixed SAMs. Due to repulsive intermolecular interaction, the Langmuir isotherm model does not fit the adsorption kinetics of these biphenyl thiols, and a new Ising model was developed to fit the kinetics data. The equilibrium structures of SAMs and mixed SAMs depend on the polarity of the solution from which they were assembled. Infrared spectroscopy suggests that biphenyl moieties in SAMs on gold have small tilt angles with respect to the surfaces normal. Wetting studies shows that surfaces of these SAMs are stable for months, thus providing stable model surfaces that can be engineered at the molecular level. Such molecular engineering is important for nucleation and growth studies. The morphology of glycine crystals grown on SAM surfaces depends on the structure of the nucleating glycine layer, which, in turn, depends on the H-bonding of these molecules with the SAM surface. Finally, the adhesion of PDMS cross-linked networks to SAM surfaces depends on the concentration of interfacial H-bonding. This non-linear relationship suggests that the polymeric nature of the elastomer results in a collective H-bonding effect.

Vitamin B12S-promoted model rearrangement of methylmalonate to succinate is not a free radical reaction.

To probe for free radical intermediates in the model methylmalonate to succinate rearrangements promoted by vitamin B12s, a model series with a pentenyl side chain radical trap has been devised. The control free radical, generated by tri-n-butyltin hydride treatment of bromomethyl-pentenylmalonate thioester, undergoes rapid cyclization to the six-membered ring, and, as anticipated, no succinate rearrangement product is detected. By contrast when the bromide is treated with vitamin B12s, little cyclized product is observed; the major product is the pentenyl succinate. This result demonstrates that the latter rearrangement does not follow a free radical pathway.