Interfacial properties of the brine + carbon dioxide + oil + silica system.

Molecular dynamics simulations of the H2O + CO2 + aromatic hydrocarbon and H2O + CO2 + benzene + silica (hydrophilic) systems are performed to gain insights into CO2-enhanced oil recovery (EOR) processes. For comparison purposes, an overview of the previous simulation studies of the interfacial properties of the brine + CO2 + alkane + silica system is also presented. In general, the water contact angle (CA) of the H2O + CO2 + silica (hydrophilic) system increased with pressure and decreased with temperature. The CAs of the H2O + hydrocarbon + silica (hydrophilic) system are not significantly affected by temperature and pressure. The simulated CAs were in the ranges of about 58°-77° and 81°-93° for the H2O + hexane + silica (hydrophilic) and the H2O + aromatic hydrocarbon + silica (hydrophilic) systems, respectively. In general, these CAs were not significantly influenced by the addition of CO2. The simulated CAs were in the ranges of about 51.4°-95.0°, 69.1°-86.0°, and 72.0°-87.9° for the brine + CO2 + silica (hydrophilic), brine + hexane + silica (hydrophilic), and brine + CO2 + hexane + silica (hydrophilic) systems, respectively. All these CAs increased with increasing NaCl concentration. The adhesion tension of the brine + silica (hydrophilic) system in the presence of CO2 and/or hexane decreased with increasing salt concentration. The simulated CAs were in the range of about 117°-139° for the H2O + alkane + silica (hydrophobic) system. These CAs are increased by the addition of CO2. At high pressures, the distributions of H2O normal to the silica (hydrophobic) surface in the droplet region of the H2O + silica system were found to be strongly affected by the presence of CO2. These insights might be key for optimizing the performance of the miscible CO2 water-alternating-gas injection schemes widely used for EOR.

Diagnosis and predicted outcomes of patients with cystic fibrosis related liver disease considered for lung transplantation.

INTRODUCTION: There is no gold standard criterion for the diagnosis of cystic fibrosis-related liver disease (CFRLD) and there is uncertainty over its impact on the outcome of lung transplantation. METHOD: Lung recipients (n = 238) were divided into two groups-CFRLD and non-CFRLD based on a modified aspartate aminotransferase-to-platelet ratio index (APRI) score (mAPRI) to diagnose CFRLD and predict severity of liver disease. Groups were compared to assess validity of the diagnosis and survival outcomes. RESULT: The new diagnostic criterion was effective at differentiating CFRLD from non-CFRLD. There was no significant difference in the survival between two groups at short, medium, or long term demonstrated by the Kaplan-Meier plot with survival of 85%, 73%, 47%, 18.6%, and 4.7% at 1, 2, 5, 10, and 15 years respectively. A mAPRI score of greater than .2 had a sensitivity of 43.0% but a specificity of 82.5 % for diagnosis of CFRLD and 46.5% sensitivity but 100% specificity in predicting an ultrasound/biopsy proven hepatic abnormality associated with CFRLD. CONCLUSION: A mAPRI sore is a highly specific non-invasive tool for diagnosis of CFRLD. Recipients with CFRLD but grossly preserved hepatocellular function have a similar outcome to patients without CFRLD.

Interfacial properties of the hexane + carbon dioxide + water system in the presence of hydrophilic silica.

Molecular dynamics simulations were conducted to study the interfacial behavior of the CO2 + H2O and hexane + CO2 + H2O systems in the presence of hydrophilic silica at geological conditions. Simulation results for the CO2 + H2O and hexane + CO2 + H2O systems are in reasonable agreement with the theoretical predictions based on the density functional theory. In general, the interfacial tension (IFT) of the CO2 + H2O system exponentially (linearly) decreased with increasing pressure (temperature). The IFTs of the hexane + CO2 + H2O (two-phase) system decreased with the increasing mole fraction of CO2 in the hexane/CO2-rich phase xCO2 . Here, the negative surface excesses of hexane lead to a general increase in the IFTs with increasing pressure. The effect of pressure on these IFTs decreased with increasing xCO2 due to the positive surface excesses of carbon dioxide. The simulated water contact angles of the CO2 + H2O + silica system fall in the range from 43.8° to 76.0°, which is in reasonable agreement with the experimental results. These contact angles increased with pressure and decreased with temperature. Here, the adhesion tensions are influenced by the variations in fluid-fluid IFT and contact angle. The simulated water contact angles of the hexane + H2O + silica system fall in the range from 58.0° to 77.0° and are not much affected by the addition of CO2. These contact angles increased with pressure, and the pressure effect was less pronounced at lower temperatures. Here, the adhesion tensions are mostly influenced by variations in the fluid-fluid IFTs. In all studied cases, CO2 molecules could penetrate into the interfacial region between the water droplet and the silica surface.

Intersecting sex-related inequalities in self-reported testing for and prevalence of Non-Communicable Disease (NCD) risk factors in Kerala.

BACKGROUND: Non-Communicable Diseases (NCDs) are among India's top burdens, particularly in states like Kerala, which is at an advanced stage of the epidemiological transition. Evidence in India points towards intersectional inequalities in risk factors of NCDs and testing, both of which are understudied in Kerala. We estimated the self-reported testing and prevalence of key NCD risk factors-blood pressure (BP) and blood glucose (BG) comparing Kerala men and women across educational, wealth, religion, as well as caste and tribal status subgroups. METHOD: A multistage random sample survey of 3398 women and 2982 men aged 30 years and over was administered in 4 districts of Kerala from July to October 2019. Descriptive analysis for men and women was undertaken using survey weights. Slope index of Inequality and Relative Concentration Index for wealth and education related inequalities, and, Weighted Mean Difference from Mean and Index of Disparity for caste and tribal status, as well as religion related inequalities were calculated using World Health Organisation's Health Equity Assessment Toolkit Plus and Stata 12. RESULTS: A significantly higher proportion of women reported BP and BG testing by medical personnel in the previous year than men (BP Testing among Women (BPTw): 90.3% vs BP Testing among Men (BPTM):80.8%, BG Testing among Women (BGTw): 86.2% vs BG Testing among Women (BGTM):78.3%). Among those tested, more women (11.2%) than men (7.9%) reported High Blood Pressure (HBP) but not High Blood Glucose (HBG). Testing for BP was concentrated among less-educated women while BG testing was concentrated among both less educated women and men. HBP and HBG were concentrated among less educated and wealthier groups. Although sex differences were insignificant across caste and tribal status and religion subgroups, magnitude of inequalities was high for HBP and HBG. CONCLUSION: Distinct patterns of sex inequalities were present in self-reported testing and prevalence of NCD risk factors in Kerala. Education and wealth seem to be associated with testing while prevalence appeared to vary by religious groups. Given the low rates of illiteracy, it is encouraging but maybe a data artefact that a small population of less-educated persons was getting tested; however, exclusion of poor groups and inequalities by other dimensions raise concerns. Further exploration is needed to understand underlying mechanisms of these inequalities to ensure we leave no one behind.

Soluble ACE2 and angiotensin II levels are modulated in hypertensive COVID-19 patients treated with different antihypertension drugs.

PURPOSE: This study examines the effect of antihypertensive drugs on ACE2 and Angiotensin II levels in hypertensive COVID-19 patients. INTRODUCTION: Hypertension is a common comorbidity among severe COVID-19 patients. ACE2 expression can be modulated by antihypertensive drugs such as ACEis and ARBs, which may affect COVID-19's prognosis. BB and CCB reduce mortality, according to some evidence. Their effect on circulating levels of ACE2 and angiotensin II, as well as the severity of COVID-19, is less well studied. MATERIALS AND METHODS: The clinical data were collected from 200 patients in four different antihypertensive medication classes (ACEi, ARB, BB, and CCB). Angiotensin II and ACE2 levels were determined using standard ELISA kits. ACE2, angiotensin II, and other clinical indices were evaluated by linear regression models. RESULTS: Patients on ACEi (n = 57), ARB (n = 68), BB (n = 15), or CCB (n = 30) in this study had mild (n = 76), moderate (n = 76), or severe (n = 52) COVID-19. ACE2 levels were higher in COVID-19 patients with severe disease (p = 0.04) than mild (p = 0.07) and moderate (p = 0.007). The length of hospital stay is correlated with ACE2 levels (r = 0.3, p = 0.003). Angiotensin II levels decreased with severity (p = 0.04). Higher ACE2 levels are associated with higher CRP and D-dimer levels. Elevated Angiotensin II was associated with low levels of CRP, D-dimer, and troponin. ACE2 levels increase with disease severity in patients taking an ARB (p = 0.01), patients taking ACEi, the degree of disease severity was associated with a decrease in angiotensin II. BB patients had the lowest disease severity. CONCLUSION: We found different levels of soluble ACE2, and angiotensin II are observed among COVID-19 patients taking different antihypertensive medications and exhibiting varying levels of disease severity. COVID-19 severity increases with elevated ACE2 levels and lower angiotensin II levels indicating that BB treatment reduces severity regardless of levels of ACE2 and angiotensin II.

Feasibility and acceptability of a physical activity behavioural modification tele-coaching intervention in lung transplant recipients.

BACKGROUND: Despite improvements in pulmonary function following lung transplantation (LTx), physical activity levels remain significantly lower than the general population. To date, there is little research investigating interventions to improve daily physical activity in LTx recipients. This study assessed the feasibility and acceptability of a novel, 12-weeks physical activity tele-coaching (TC) intervention in LTx recipients. METHODS: Lung transplant recipients within 2 months of hospital discharge were recruited and randomised (1:1) to TC or usual care (UC). TC consists of a pedometer and smartphone app, allowing transmission of activity data to a platform that provides feedback, activity goals, education, and contact with the researcher as required. Recruitment and retention, occurrence of adverse events, intervention acceptability and usage were used to assess feasibility. RESULTS: Key criteria for progressing to a larger study were met. Of the 15 patients eligible, 14 were recruited and randomised to TC or UC and 12 completed (67% male; mean ± SD age; 58 ± 7 years; COPD n = 4, ILD n = 6, CF n = 1, PH n = 1): TC (n = 7) and UC (n = 5). TC was well accepted by patients, with 86% indicating that they enjoyed taking part. Usage of the pedometer was excellent, with all patients wearing it for over 90% of days and rating the pedometer and telephone contact as the most vital aspects. There were no adverse events related to the intervention. After 12 weeks, only TC displayed improvements in accelerometry steps/day (by 3475 ± 3422; p = .036) and movement intensity (by 153 ± 166 VMU; p = .019), whereas both TC and UC groups exhibited clinically important changes in physical SF-36 scores (by 11 ± 14 and 7 ± 9 points, respectively). CONCLUSION: TC appears to be a feasible, safe, and well-accepted intervention in LTx.

Chest X-ray Findings and Hyponatremia in COVID-19 Pneumonia Patients.

BACKGROUND: The World Health Organization declared the coronavirus disease-2019 (COVID-19) a pandemic in December 2019. COVID-19 can affect most organs of the body but predominantly affects the lungs. Chest infection is associated with hyponatremia primarily due to inappropriate ectopic secretion of antidiuretic hormone. We conducted a six-month retrospective observational study to evaluate the relationship between chest X-ray (CXR) radiological findings and serum sodium levels. Our secondary goal was to assess the relationship between CXR findings and patient outcomes. AIM OF THE STUDY: To assess the relationship between the initial CXR findings, hyponatremia severity, and outcome in COVID-19 infected patients. MATERIALS AND METHODS: We conducted a retrospective review of CXR findings of COVID-19 patients aged > 18 years. The patients were healthy and had no history of hyponatremia before COVID-19 infection. All recruited patients were admitted to one of four hospitals in Qatar (Hazm Mebaireek General Hospital, Communicable Disease Center, and all affiliated quarantine centers managed under the Communicable Disease Centre, Mesaieed Hospital, and Ras Laffan Hospital) between March and June 2020. We excluded patients with factors that contributed to hyponatremia. Three score grades were established to describe the CXR findings. Patients were divided into three groups by the principal researcher according to their serum sodium levels. A radiologist evaluated the CXR findings with the patient and group information obscured. The principal researcher collected the X-ray scores for analysis with the serum sodium levels. We used SPSS for Windows, Version 15.0. (SPSS Inc., Chicago, IL, USA) and STATA Package Version 12.0 (StataCorp, College Station, TX, USA) to analyze the data. A p-value ≤  0.05 was considered significant. RESULTS: A total of 414 CXR patients with COVID-19 were recruited; 275 patients had hyponatremia and 139 had normal sodium levels and were used as the control group. Patients with normal serum sodium and hyponatremia were classified into three categories based on the CXR findings. Grade 0 (95), Grade 1 (43), and Grade 2 (137) hyponatremic patients were reported. The mean sodium levels were 133.6, 131.3, and 127.2 mmol/L for Grades 0, 1, and 2, respectively (p < 0.001). More than 95% of the patients who developed hyponatremia were >30 years. Moderate and severe hyponatremia was more prevalent in patients with Grade 1 or Grade 2 CXR findings and were >30 years. CONCLUSION: Serum sodium levels in COVID-19 patients correlated well with the severity of the CXR findings observed at the early disease stage. Furthermore, simple CXR scores can be used to identify COVID-19 patients at a higher risk of hyponatremia, length of hospital stay, medical care support type, and mortality.

Interfacial behavior of the decane + brine + surfactant system in the presence of carbon dioxide, methane, and their mixture.

Molecular dynamics simulations are carried out to get insights into the interfacial behavior of the decane + brine + surfactant + CH4 + CO2 system at reservoir conditions. Our results show that the addition of CH4, CO2, and sodium dodecyl sulfate (SDS) surfactant at the interface reduces the IFTs of the decane + water and decane + brine (NaCl) systems. Here the influence of methane was found to be less pronounced than that of carbon dioxide. As expected, the addition of salt increases the IFTs of the decane + water + surfactant and decane + water + surfactant + CH4/CO2 systems. The IFTs of these surfactant-containing systems decrease with temperature and the influence of pressure is found to be less pronounced. The atomic density profiles show that the sulfate head groups of the SDS molecules penetrate the water-rich phase and their alkyl tails are stretched into the decane-rich phase. The sodium counterions of the surfactant molecules are located very close to their head groups. Furthermore, the density profiles of water and salt ions are hardly affected by the presence of the SDS molecules. However, the interfacial thickness between water and decane/CH4/CO2 molecules increases with increasing surfactant concentration. An important result is that the enrichment of CH4 and/or CO2 in the interfacial region decreases with increasing surfactant concentration. These results may be useful in the context of the water-alternating-gas approach that has been utilized during CO2-enhanced oil recovery operations.

In vitro effects of combined iron chelation, antibiotics and matrix disruption on clinical isolates of Pseudomonas aeruginosa.

OBJECTIVES: Pseudomonas aeruginosa is an important pathogen in chronic suppurative respiratory diseases, with adverse effects on severity, healthcare utilization and quality of life. Aerosolized combined biofilm disruption and iron chelators offer novel proof-of-concept for improving airway antimicrobial efficacy. Our aim was to assess the activity of desferrioxamine, Dornase alfa (DNase) and antibiotics on biofilm formation and against mature preformed biofilms of P. aeruginosa. METHODS: Fifty-six isolates of P. aeruginosa were screened for biofilm production and seven isolates with varying capacity to form biofilms were referred for further study. Three antibiotics (colistin, tobramycin and ciprofloxacin) as well as desferrioxamine and DNase were assessed for their ability to prevent biofilm formation using the crystal violet assay. The same method was used to assess their impact on mature biofilms. Each agent, as well as combinations of these agents, was also assessed for its effect on the metabolic activity and viability of preformed P. aeruginosa biofilm by the resazurin reduction assay and by performing viable counts. RESULTS: Antibiotics alone prevented the development of biofilms and partly reduced the viability of mature biofilms. Desferrioxamine and DNase did not reduce biofilm formation. For most isolates, desferrioxamine and DNase did not offer any clear advantage over the use of antibiotics alone with respect to reducing the viability of Pseudomonas biofilms. CONCLUSIONS: Colistin, tobramycin and ciprofloxacin prevented biofilm formation by P. aeruginosa and reduced the viability of mature biofilms. For most isolates, there was no clear advantage of combining these antimicrobials with desferrioxamine or DNase.

Field-testing of primary health-care indicators, India.

OBJECTIVE: To develop a primary health-care monitoring framework and health outcome indicator list, and field-test and triangulate indicators designed to assess health reforms in Kerala, India, 2018-2019. METHODS: We used a modified Delphi technique to develop a 23-item indicator list to monitor primary health care. We used a multistage cluster random sampling technique to select one district from each of four district clusters, and then select both a family and a primary health centre from each of the four districts. We field-tested and triangulated the indicators using facility data and a population-based household survey. FINDINGS: Our data revealed similarities between facility and survey data for some indicators (e.g. low birth weight and pre-check services), but differences for others (e.g. acute diarrhoeal diseases in children younger than 5 years and blood pressure screening). We made four critical observations: (i) data are available at the facility level but in varying formats; (ii) established global indicators may not always be useful in local monitoring; (iii) operational definitions must be refined; and (iv) triangulation and feedback from the field is vital. CONCLUSION: We observe that, while data can be used to develop indices of progress, interpretation of these indicators requires great care. In the attainment of universal health coverage, we consider that our observations of the utility of certain health indicators will provide valuable insights for practitioners and supervisors in the development of a primary health-care monitoring mechanism.

Plasma ammonia concentrations in extremely low birthweight infants in the first week after birth: secondary analysis from the ProVIDe randomized clinical trial.

BACKGROUND: Little is known about normative ammonia concentrations in extremely low birthweight (ELBW) babies and whether these vary with birth characteristics. We aimed to determine ammonia concentrations in ELBW babies in the first week after birth and relationships with neonatal characteristics and protein intake. METHODS: Arterial blood samples for the measurement of plasma ammonia concentration were collected within 7 days of birth from ProVIDe trial participants in six New Zealand neonatal intensive care units. RESULTS: Three hundred and twenty-two babies were included. Median (range) gestational age was 25.7 (22.7-31.6) weeks. Median (interquartile range (IQR)) ammonia concentration was 102 (80-131) µg/dL. There were no statistically significant associations between ammonia concentrations and birthweight or sex. Ammonia concentrations were weakly correlated with mean total (Spearman's rs = 0.11, P = 0.047) and intravenous (rs = 0.13, P = 0.02) protein intake from birth, gestational age at birth (rs = -0.13, P = 0.02) and postnatal age (rs = -0.13, P = 0.02). CONCLUSIONS: Plasma ammonia concentrations in ELBW babies are similar to those of larger and more mature babies and only weakly correlated with protein intake. Currently, recommended thresholds for investigation of hyperammonaemia are appropriate for ELBW babies. Protein intake should not be limited by concerns about potential hyperammonaemia.

Epidemiological characteristics of de novo hepatitis B infection in liver transplant recipients-An experience from a tertiary care centre in Qatar.

BACKGROUND: The emergence of hepatitis B surface antigen in a patient with previously negative hepatitis B virus (HBV) serology post-orthotropic liver transplant (OTLX) is known as de novo hepatitis B (DNHB). As there are no data on patients with DNHB available from Qatar, we aim to do a pioneer study indexing their clinical profile and epidemiology of patients with DNHB in Qatar. MATERIALS AND METHODS: This descriptive epidemiological study was done by retrospectively reviewing records of 159 post-OTLX patients. HBV serology of these patients post-OTLX was reviewed, and 17 were identified as DNHB cases. Baseline epidemiological characteristics were defined and compared between DNHB cases and the rest. DNHB cases were analyzed statistically using the chi-square test and Kaplan-Meier curve. RESULTS: The majority of the subjects were men (65%) and Qataris (40%). Mean age was 57.4 ± 12.5 years. Bulk of them underwent OTLX in China (44%). The overall incidence of DNHB was 10.7%, with transplants in China having significantly higher incidence than transplants from all other countries. The mortality rate was 23.5% in DNHB cases compared to 2.8% in non-DNHB. 67% of patients survived at least 64 months after the diagnosis of DNHB. Five-year survival did not vary significantly between those with DNHB and those without. CONCLUSION: Orthotropic liver transplant in centers selecting donors liberally without screening for HBV poses the risk of DNHB. We recommend having protective levels of HBs antibodies before OTLX. Prophylactic antiviral treatment should be considered until peri-operative HBV transmission has been excluded by screening hepatic tissue for HBV DNA.

Standardised neonatal parenteral nutrition formulations - Australasian neonatal parenteral nutrition consensus update 2017.

BACKGROUND: The first consensus standardised neonatal parenteral nutrition formulations were implemented in many neonatal units in Australia in 2012. The current update involving 49 units from Australia, New Zealand, Singapore, Malaysia and India was conducted between September 2015 and December 2017 with the aim to review and update the 2012 formulations and guidelines. METHODS: A systematic review of available evidence for each parenteral nutrient was undertaken and new standardised formulations and guidelines were developed. RESULTS: Five existing preterm Amino acid-Dextrose formulations have been modified and two new concentrated Amino acid-Dextrose formulations added to optimise amino acid and nutrient intake according to gestation. Organic phosphate has replaced inorganic phosphate allowing for an increase in calcium and phosphate content, and acetate reduced. Lipid emulsions are unchanged, with both SMOFlipid (Fresenius Kabi, Australia) and ClinOleic (Baxter Healthcare, Australia) preparations included. The physicochemical compatibility and stability of all formulations have been tested and confirmed. Guidelines to standardise the parenteral nutrition clinical practice across facilities have also been developed. CONCLUSIONS: The 2017 PN formulations and guidelines developed by the 2017 Neonatal Parenteral Nutrition Consensus Group offer concise and practical instructions to clinicians on how to implement current and up-to-date evidence based PN to the NICU population.

Tracheal Allotransplantation-Lessons Learned.

Reconstruction of long tracheal defects still proves to be a challenge. Free fasciocutaneous flaps with cartilaginous struts or an allotransplant trachea have been reported but not been widely performed. This article reports with the experience of using a tracheal allotransplant in such a defect. A 43-year-old lady presented with adenoid cystic carcinoma involving the entire trachea from subglottic area up to the carina, leading to a life-threatening airway occlusion. After preliminary stenting, allotransplant trachea obtained from a brain-dead individual was revascularized in the forearm of the patient after mechanical decellularization to reduce the immune load and fulfil the need for immunosuppression in the background of active cancer. Subsequently, the trachea and larynx were resected. The vascularized neotrachea was transferred successfully into the neck. The patient did well initially but succumbed to a fatal hemorrhage due to innominate vein aneurysmal rupture on the 22nd day after the transplant. The technical details of resection, fabrication of the neotrachea, its transfer, and the lessons learnt in this tracheal allotransplant are described.

Effects of drug abuse, smoking and alcohol on donor hearts and lungs.

Potential heart and lung donors with a history of illicit drugs and/or smoking and alcohol are frequently offered, though there is no clear guidance on when it is safe to use these organs. A review of the literature on effects of drugs, alcohol and smoking on donor outcomes, and the effects of these on the intact heart and lung was undertaken. There has been a marked increase in deaths from opioid abuse in many developed countries, though recent evidence suggests that outcomes after cardiothoracic transplantation are equivalent to nonopioid donor causes of death. For donor smoking, there is an increased risk with lung transplantation; however, that risk is less when compared to further waiting on the transplant list for a nonsmoking alternative. Heavy alcohol consumption does not adversely affect heart transplantation, and there is no clear evidence of adverse outcomes after lung transplantation. There are no overall effects of cannabis or cocaine on survival after heart or lung transplantation. In all these cases, careful donor assessment can establish if a particular organ can be used. In most cases, use of drugs requires careful assessment, but is not in of itself a contraindication to cardiothoracic transplantation.

Deformation mechanisms of polytetrafluoroethylene at the nano- and microscales.

Polytetrafluoroethylene (PTFE) has not only a low coefficient of friction but also a high wear rate. Numerous studies investigating the possibility of reducing wear and the mechanisms of deformation have been conducted using experimental and computational studies. In this paper the deformation and mechanical failure of single chains and bulk PTFE are investigated using molecular dynamics (MD). Due to the length scale limitations of the model that MD simulations can investigate, a coarse-grained model is developed and PTFE particles of varying densities are generated to investigate their mechanical properties at the microscale. The coarse-grained potential parameters and coarse-grained model of PTFE are derived from first principles based ReaxFF simulations and are then used to investigate the microscale mechanical properties of PTFE. The MD study indicates that temperature has a pronounced effect on the maximum strength of a single chain, the elastic modulus is dependent on chain length, and chains shorter than 100 Å have an increase in maximum strength. During indentation and scratch the frictional coefficient of bulk PTFE is dependent on the direction of the scratch on the PTFE substrate. The coarse-grained PTFE simulations show that indentation force is dependent on the density of PTFE, and the smoother the surface of the particle the lower the coefficient of friction. The coarse-grained model that connects the atomic and macroscales of PTFE will lead to a direct comparison with experimental PTFE thin films.

Identification and characterization of a novel bacterial ß-glucosidase that is highly specific for the ß-1,2-glucosidic linkage of sesaminol triglucoside.

A gene (PSTG2) coding for a novel ß-glucosidase belonging to glycoside hydrolase family 3 was identified in the vicinity of the previously identified ß-glucosidase gene [sesaminol triglucoside (STG)-hydrolyzing ß-glucosidase, PSTG1] in the genome of Paenibacillus sp. strain KB0549. Compared with PSTG1, recombinant PSTG2 more specifically acted on the ß-1,2-glucosidic linkage of the STG molecule to transiently accumulate a larger amount of 6-O-(ß-D-glucopyranosyl)-ß-D-glucopyranosylsesaminol.

Cerebral Vasculopathy in Coarctation of Aorta-a Rare Association.

Coarctation of aorta is a rare congenital cardiovascular condition where patients are at risk of systemic arteriopathy, including hypertension and intracranial aneurysms.1 Here we report a rare case of young ischemic stroke, who was found to be having a cerebral vasculopathy and coarctation of aorta on evaluation.

Rapid Deposition of Uniform Polydopamine Coatings on Nanoparticle Surfaces with Controllable Thickness.

Polydopamine is a bioinspired, versatile material that can adhere to bulk and nanoscale surfaces made of disparate materials to improve their physical and chemical properties in many applications. The typical methods to coat polydopamine on the nanoparticle substrates usually take several hours to a day. This work successfully applies a dispersion method to form a controllable, uniform coating on a nanoparticle surface within minutes. Using plasmonic Ag nanoparticles as a substrate, the coating thickness can be monitored using a spectroscopic method based on the extinction peak shifts of the Ag nanoparticles. The deposition rate increases with dopamine concentration; however, too much excess dopamine leads to the formation of free dopamine particles. The optimized concentration of dopamine (i.e., ∼6 mM) can be applied to other nanoparticles by normalizing the number of particles to maintain a constant concentration of dopamine per unit surface area (i.e., 1.70 × 104 dopamine/nm2). The molecular dynamics simulation reveals that the amount of hydrogen bonding increases with water content, suggesting that sufficient mixing using the dispersion tool facilitates the formation of hydrogen bonding, thus rapidly depositing PDA on the nanoparticle surface. The physical and chemical properties (e.g., pH response and thermal stability) can be tailored by varying the coating thickness due to the changes in the number of hydrogen bonds and the conformation of π-π interactions. This dispersion method provides a facile means to control the PDA coating thickness on nanoparticle surfaces and thus the surface properties of nanoparticles toward various applications.