Collodial particles at a range of fluid-fluid particles

The study of solid particles residing at fluid-fluid interfaces has become an established area in surface and colloid science recently experiencing a renaissance since around 2000. Particles at interfaces arise in many industrial products and processes like anti-foam formulations, crude oil emulsions, aerated foodstuffs and flotation. Although they act in many ways like traditional surfactant molecules, they offer distinct advantages also and the area is now multi-disciplinary involving research in the fundamental science and potential applications. In this Feature Article, a flavour of some of this interest is given based on recent work from our own group and includes the behaviour of particles at oil-water, air-water, oil-oil, air-oil and water-water interfaces. The materials capable of being prepared by assembling various kinds of particles at fluid interfaces include particle-stabilised emulsions, particle-stabilised aqueous and oil foams, dry liquids, liquid marbles and powdered emulsions

Immunoglobulin Allotypes and Immune Response to Meningococcal Group B Polysaccharide

Serum samples were collected from 120 healthy adult volunteers (105 Caucasians and 15 Negros) before and after immunization with meningococcal polysaccharide (MPS) group B vaccine. Antibodies to MPS group B were measured and sera were typed for several Gm and Km(l) allotypes. A significant association was found between the Km(l) allotype and immune response to MPS group B in Caucasians

Clinical evaluation of the FloTrac/VigileoTM system and two established continuous cardiac output monitoring devices in patients undergoing cardiac surgery†‡

Background Assessment of cardiac output (CO) by the FloTrac/Vigileo™ system may offer a less invasive means of determining the CO than either the pulmonary artery catheter (PAC) or the PiCCOplus™ system. The aim of this study was to compare CO measurements made using the FloTrac/Vigileo™ system with upgraded software (FCO, Edwards Lifesciences, Irvine CA, USA), the PiCCOplus™ system (PCO, Pulsion Medical Systems, Munich, Germany) and continuous CO monitoring using a PAC (CCO; Vigilance™ monitoring, Edwards Lifesciences, Irvine CA, USA) with intermittent pulmonary artery thermodilution (ICO). The study was conducted in patients undergoing elective cardiac surgery. Methods Thirty-one patients with preserved left ventricular function were enrolled. CCO, FCO, and PCO were recorded in the perioperative period at six predefined time points after achieving stable haemodynamic conditions; ICO was determined from the mean of three bolus injections. Bland-Altman analysis was used to compare CCO, FCO, and PCO with ICO. Results Bland-Altman analysis revealed a comparable mean bias and limits of agreement for all tested continuous CO monitoring devices using ICO as reference method. Agreement for all devices decreased in the postoperative period. Conclusion The performance of the FloTrac/Vigileo™ system, the PiCCOplus™, and the Vigilance™ CCO monitoring for CO measurement were comparable when tested against intermittent thermodilution in patients undergoing elective cardiac surger

Patient well‐being after general anaesthesia: a prospective, randomized, controlled multi‐centre trial comparing intravenous and inhalation anaesthesia

Background. The aim of this study was to assess postoperative patient well‐being after total i.v. anaesthesia compared with inhalation anaesthesia by means of validated psychometric tests. Methods. With ethics committee approval, 305 patients undergoing minor elective gynaecologic or orthopaedic interventions were assigned randomly to total i.v. anaesthesia using propofol or inhalation anaesthesia using sevoflurane. The primary outcome measurement was the actual mental state 90 min and 24 h after anaesthesia assessed by a blinded observer using the Adjective Mood Scale (AMS) and the State‐Trait‐Anxiety Inventory (STAI). Incidence of postoperative nausea and vomiting (PONV) and postoperative pain level were determined by Visual Analogue Scale (VAS) 90 min and 24 h after anaesthesia (secondary outcome measurements). Patient satisfaction was evaluated using a VAS 24 h after anaesthesia. Results. The AMS and STAI scores were significantly better 90 min after total i.v. anaesthesia compared with inhalation anaesthesia (P=0.02, P=0.05, respectively), but equal 24 h after both anaesthetic techniques (P=0.90, P=0.78, respectively); patient satisfaction was comparable (P=0.26). Postoperative pain was comparable in both groups 90 min and 24 h after anaesthesia (P=0.11, P=0.12, respectively). The incidence of postoperative nausea was reduced after total i.v. compared with inhalation anaesthesia at 90 min (7 vs 35%, P<0.001), and 24 h (33 vs 52%, P=0.001). Conclusion. Total i.v. anaesthesia improves early postoperative patient well‐being and reduces the incidence of PONV. Br J Anaesth 2003; 91: 631-

Glial βii spectrin contributes to paranode formation and maintenance

Action potential conduction along myelinated axons depends on high densities of voltage-gated Na channels at the nodes of Ranvier. Flanking each node, paranodal junctions (paranodes) are formed between axons and Schwann cells in the peripheral nervous system (PNS) or oligodendrocytes intheCNS. Paranodal junctions contribute to both no deassembly and maintenance. Despitetheir importance, the molecular mechanisms responsible for paranode assembly and maintenance remain poorly understood. βII spectrin is expressed in diverse cells and is an essential part of the submembranous cytoskeleton. Here, we show that Schwann cell βII spectrin is highly enriched at paranodes. To elucidate the roles of glial βII spectrin, we generated mutant mice lacking βII spectrin in myelinating glial cells by crossing mice with a floxed allele of Sptbn1 with Cnp-Cre mice, and analyzed both male and female mice. Juvenile (4 weeks) and middle-aged (60 weeks) mutant mice showed reduced grip strength and sciatic nerve conduction slowing, whereas no phenotype was observed between 8 and 24 weeks of age. Consistent with these findings, immunofluorescence microscopy revealed disorganized paranodes in the PNS and CNS of both postnatal day 13 and middle-aged mutant mice, but not in young adult mutant mice. Electron microscopy confirmed partial loss of transverse bands at the paranodal axoglial junction in the middle-aged mutant mice in both the PNS and CNS. These findings demonstrate that a spectrin-based cytoskeleton in myelinating glia contributes to formation and maintenance of paranodal junctions.Fil: Susuki, Keiichiro. Baylor College of Medicine; Estados UnidosFil: Zollinger, Daniel R.. Baylor College of Medicine; Estados UnidosFil: Chang, Kae Jiun. Baylor College of Medicine; Estados UnidosFil: Zhang, Chuansheng. Baylor College of Medicine; Estados UnidosFil: Huang, Claire Yu Mei. Baylor College of Medicine; Estados UnidosFil: Tsai, Chang Ru. Baylor College of Medicine; Estados UnidosFil: Galiano, Mauricio Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; Argentina. Baylor College of Medicine; Estados UnidosFil: Liu, Yanhong. Baylor College of Medicine; Estados UnidosFil: Benusa, Savannah D.. Virginia Commonwealth University; Estados UnidosFil: Yermakov, Leonid M.. Wright State University; Estados UnidosFil: Griggs, Ryan B.. Wright State University; Estados UnidosFil: Dupree, Jeffrey L.. Virginia Commonwealth University; Estados UnidosFil: Rasband, Matthew N.. Baylor College of Medicine; Estados Unido

Differences in cervical cancer screening knowledge, practices, and beliefs: An examination of survey responses

Among the identified barriers to HPV vaccination is the concern that women may compensate for their reduced susceptibility to cervical cancers by reducing cervical cancer screening. This exploratory study examined the relationship between cervical cancer screening rates and HPV vaccination. We conducted a cross-sectional survey using a convenience sample of women aged 21-35 attending a local minority health fair in July 2015. Data were analyzed in 2015-2016. Outcomes assessed were: receiving a Pap test within the last three years, awareness and comfort with current Pap test recommendations, and knowledge regarding the purpose of a Pap test. A total of 291 women were included in the analyses. Mean age was 28.5 years and 62% were non-Hispanic black. 84% had received a Pap test in the last three years and 33% had received at least one HPV vaccine. Logistic regression results showed that women who had been vaccinated did not have lower odds of having a Pap test in the past three years (OR = 1.32; 95% CI = 0.66-2.65). In an adjusted regression model controlling for age and race, vaccinated women were significantly more likely to have had a Pap test (AOR = 3.06; 95% CI = 1.37-6.83). Yet only 26% of women knew the purpose of a Pap test and the proportion who answered correctly was higher among non-Hispanic white women. Women who have been vaccinated for HPV are more likely to have been screened for cervical cancer. These results suggest areas for more robust studies examining pro-health attitudes, behaviors, and communication regarding vaccination and preventive screening

Preconditioning with sevoflurane decreases PECAM-1 expression and improves one-year cardiovascular outcome in coronary artery bypass graft surgery

Background. Cardiac preconditioning is thought to be involved in the observed decreased coronary artery reocclusion rate in patients with angina preceding myocardial infarction. We prospectively examined whether preconditioning by sevoflurane would decrease late cardiac events in patients undergoing coronary artery bypass graft (CABG) surgery. Methods. Seventy-two patients scheduled for elective CABG surgery were randomized to preconditioning by sevoflurane (10 min at 4 vol%) or placebo. For all patients, follow-up of adverse cardiac events was obtained 6 and 12 months after surgery. Transcript levels for platelet-endothelial cell adhesion molecule-1 (PECAM-1/CD31), catalase and heat shock protein 70 (Hsp70) were determined in atrial biopsies after sevoflurane preconditioning. Results. Pharmacological preconditioning by sevoflurane reduced the incidence of late cardiac events during the first year after CABG surgery (sevoflurane 3% vs 17% in the placebo group, log-rank test, P=0.038). One patient in the sevoflurane group and three patients in the placebo group experienced new episodes of congestive heart failure and three additional patients had coronary artery reocclusion. Perioperative peak concentrations for myocardial injury markers were higher in patients with subsequent late cardiac events [NTproBNP, 9031 (4125) vs 3049 (1906) ng litre−1, P<0.001; cTnT, 1.31 (0.88) vs 0.46 (0.29) µg litre−1, P<0.001]. Transcript levels were reduced for PECAM-1 and increased for catalase but unchanged for Hsp70 in atrial biopsies after sevoflurane preconditioning. Conclusions. This prospective randomized clinical study provides evidence of a protective role for pharmacological preconditioning by sevoflurane in late cardiac events in CABG patients, which may be related to favourable transcriptional changes in pro- and antiprotective protein

Gold catalysts for the synthesis of aromatic azocompounds from nitroaromatics in one step

[EN] One-step selective hydrogenation of nitroaromatics to obtain symmetric azocompounds with high yields has been performed with a gold supported on cerium oxide catalysts. Au/TiO2 and Au/CeO2 catalysts direct the reaction by two different pathways and with different selectivities. In situ FTIR studies reveal that the surface concentration of the intermediate nitrosobenzene is decisive in directing the reaction trough the different reaction pathways. In this way, while on Au/TiO2 a fast hydrogenation of the nitrosobenzene intermediate leads to a low surface concentration of the nitrosocompound, on Au/CeO2 nitrosobenzene is more stabilized on the catalyst surface leading to a lower hydrogenation and a higher coupling rate, resulting in high selectivities to azobenzene. On Au/CeO2, the relative weak adsorption of the azo with respect to the azoxycompound on the catalyst surface avoids the consecutive hydrogenation of azocompounds to the corresponding anilines until all the azoxy has been consumed. Asymmetric azobenzenes have also been obtained with very high yields on TiO2, through the Mills reaction.The authors wish to acknowledge the financial support from the Spanish Ministries of Education and Science and Economy and Competitiveness under the project Consolider-Ingenio 2010 (CSD2009-00050 "Development of more efficient catalysts for the design of sustainable chemical processes and clean energy production") and the Severo Ochoa program (SEV-2012-0267), respectively. D.C. thanks the Spanish MEC for postgraduate scholarship, project MAT2006-14274-C02-01.Cómbita Merchán, DF.; Concepción Heydorn, P.; Corma Canós, A. (2014). Gold catalysts for the synthesis of aromatic azocompounds from nitroaromatics in one step. Journal of Catalysis. 311:339-349. https://doi.org/10.1016/j.jcat.2013.12.014S33934931

Effect of Ce and Sb on Primary Graphite Growth in Cast Irons

It is well-known that if certain trace elements are present in cast iron melts the morphology of the graphite precipitates can be altered. In order to understand the effect of doping elements on primary growth of graphite, pure Fe–Sb alloys were prepared by induction melting. They were then placed in graphite crucibles and heated to a temperature above the Fe–C eutectic so that the charge became saturated in carbon and melted. To obtain Fe–Ce alloys, metallic Ce was added at the bottom of a graphite crucible and covered with iron, and then heated as for the Fe–Sb charge. In both cases, the melt was then cooled and held slightly above the eutectic temperature so that primary graphite crystals, which had nucleated on the crucible walls and then detached from it, could grow freely in the melt. The influence of the added elements on graphite growth was revealed by the change in the shape and distribution of the crystals compared to those obtained in similar experiments carried out with pure Fe. The experiments were made in air and vacuum so as to point out possible interactions between the elements present in the melt and oxygen