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• Repeat SARS-CoV-2 testing after admission is key in suspicious cases • Whole genome sequencing can assist with outbreak investigations • Increased patient contact time is a risk factor for nosocomial SARS-CoV-2 infection • Performing aerosol-generating procedures increases nosocomial SARS-CoV-2 risk Despite several outbreaks of SARS-CoV-2 amongst healthcare personnel (HCP) exposed to COVID-19 patients globally, risk factors for transmission remain poorly understood. We conducted an outbreak investigation and case-control study to evaluate SARS-CoV-2 transmission risk in an outbreak among HCP at an academic medical center in California that was confirmed by whole genome sequencing. A total of 7/9 cases and 93/182 controls completed a voluntary survey about risk factors. Compared to controls, cases reported significantly more patient contact time. Cases were also significantly more likely to have performed airway procedures on the index patient, particularly placing the patient on high flow nasal cannula, continuous positive airway pressure (CPAP), or bilevel positive airway pressure (BiPAP) (OR = 11.6; 95% CI = 1.7 –132.1). This study highlights the risk of nosocomial infection of SARS-CoV-2 from patients who become infectious midway into their hospitalization. Our findings also reinforce the importance of patient contact time and aerosol-generating procedures as key risk factors for HCP infection with SARS-CoV-2. Re-testing patients for SARS-CoV-2 after admission in suspicious cases and using N95 masks for all aerosol-generating procedures regardless of initial patient SARS-CoV-2 test results can help reduce the risk of SARS-COV-2 transmission to HCP. [ABSTRACT FROM AUTHOR]

• Higher prevalence of COVID-19 in patient-facing employees. • Food and environmental service personnel had highest prevalence of COVID-19. • Symptomatic employees had a percent positivity of 4.11%. • Asymptomatic employees had a percent positivity of 0.35%. It is vital to know which healthcare personnel (HCP) have a higher chance of testing positive for severe acute respiratory syndrome coronavirus 2 (COVID-19). A retrospective analysis was conducted at Stanford Children's Health (SCH) and Stanford Health Care (SHC) in Stanford, California. Analysis included all HCP, employed by SCH or SHC, who had a COVID-19 reverse transcriptase polymerase chain reaction (RT-PCR) test resulted by the SHC Laboratory, between March 1, 2020 and June 15, 2020. The primary outcome was the RT-PCR percent positivity and prevalence of COVID-19 for HCP and these were compared across roles. SCH and SHC had 24,081 active employees, of which 142 had at least 1 positive COVID-19 test. The overall HCP prevalence of COVID-19 was 0.59% and percent positivity was 1.84%. Patient facing HCPs had a significantly higher prevalence (0.66% vs 0.43%; P =.0331) and percent positivity (1.95% vs 1.43%; P =.0396) than nonpatient facing employees, respectively. Percent positivity was higher in food service workers (9.15%), and environmental services (5.96%) compared to clinicians (1.93%; P <.0001) and nurses (1.46%; P <.0001), respectively. HCP in patient-facing roles and in support roles had a greater chance of being positive of COVID-19. [ABSTRACT FROM AUTHOR]

Abstract: A rapid and highly sensitive chiral sensing technique was developed for the chiral discrimination of mandelic acid (MA) using a quartz crystal microbalance (QCM) modified with an amide-type S-MA derivative. After the modification, the response difference when exposed to the target R-MA and S-MA was measured using a low concentration range from 10μM to 3mM combined with a novel analysis technique. For the given target concentrations, the chiral discrimination factor between S-MA and R-MA was 5.7 when using the normal frequency measurement. Remarkably, the novel sensing technique produced a chiral discrimination factor up to 9.4 based on an additional parameter at the same experimental condition. In addition, the interaction properties between the enantiomers and the chiral selector were investigated in detail using the F–R model. The main advantages of the novel sensing technique are that it is based on a real-time technique, requires a short detection time, and is highly sensitive within a 10–300μM concentration range. In particular, the excellent sensitivity for a low target concentration was because the novel analysis method revealed the mechanical difference of the intermolecular binding properties between the target enantiomers and the selector. [Copyright &y& Elsevier]

Abstract: The crystal agglomeration of Ni/Co/Mn hydroxide (NCM hydroxide) in a continuous Couette–Taylor (CT) crystallizer was experimentally studied. The NCM hydroxide crystals produced by the reaction crystallization were simultaneously coagulated to form agglomerate particles via the consecutive steps of physical adhesion of the crystals and molecular growth. Thus, the hydrodynamic conditions and supersaturation profile in the CT crystallizer were the most critical influencing parameters determining the agglomerate particle size and shape. The particle size was reduced when increasing the rotation speed of the inner cylinder in the CT crystallizer, as enhancing the intensity of the Taylor vortex broke and re-dispersed the physically adhered crystals. In addition, a high Taylor vortex changed the irregularly shaped agglomerate particles into spherical ones. The supersaturation profile in the CT crystallizer was prolonged when increasing the mean residence time and decreasing the feed concentration, thereby enlarging the particle size. Similarly, a chelating reaction also prolonged the supersaturation profile in the CT crystallizer, resulting in a larger particle size. In the agglomeration, the individual crystals created a hexagonal system stacked on the (001) face, meaning that the particles were mostly covered by the (101) face. In general, under the tested operating conditions, the CT crystallizer was able to produce agglomerate particles that were narrowly distributed and smaller than 5μm in size within 10min of the mean residence time. [Copyright &y& Elsevier]

Abstract: Sonication and turbulent agitation were used to investigate the mechanism of crystal aggregation and agglomeration during the reaction crystallization of cerium carbonate. Aggregation and agglomeration occurred simultaneously during the crystallization, thus the product suspension included both crystal aggregates and agglomerates. As crystal aggregation involves the physical adhesion of crystals, the particle size changed sensitively according to the sonication energy and agitation speed during the crystallization. In contrast, since crystal agglomeration is based on molecular growth following crystal aggregation, the agglomerates were strong enough to resist the acoustic impact of the sonication and turbulent shear of the agitation during the crystallization. Thus, the crystal aggregates in the product suspension were completely re-dispersed by an acoustic after-treatment of 30W for 20min. Acoustic after-treatment was also used to determine the agglomerate size and estimate the degree of aggregation of the product suspension. As a result, sonication above 60W was found to be adequate to prevent any aggregation or agglomeration during the crystallization, regardless of the agitation conditions. [ABSTRACT FROM AUTHOR]

Abstract: Core–shell particles of SiO2/ZrO2 were developed using a sol–gel process. Spherical core particles of SiO2, 320nm in diameter, were initially prepared using tetraethylorthosilicate (TEOS), and then uniformly shelled with ZrO2 nano-particles synthesized with zirconium(IV) butoxide (TBOZ). The deposition of ZrO2 nano-particles on the SiO2 core particles was generally promoted when increasing the H2O and TBOZ concentrations and temperature of the sol–gel process. However, micron-sized homo-aggregates of ZrO2 were formed above certain concentrations of H2O and TBOZ due to self-aggregation of the nano-ZrO2 particles. It was very interesting to discover that a chemical bonding between zirconium and silicon bridged by oxygen (Si–O–Zr bond) was developed during the formation of the ZrO2 shell around the core particles, as the silane groups on the core particles were condensed with zirconium hydroxyl groups during the deposition of ZrO2. XPS and FT-IR confirmed the chemical bonding of Si–O–Zr in the core–shell particles. [Copyright &y& Elsevier]

Abstract: This study investigated the control of hydroxyl groups, one of key factors determining the surface properties of silica particles synthesized by the sol-precipitation of tetraethyl orthosilicate (TEOS). Thus, a thermal gravity analysis (TGA) was used to facilitate quantitative measurements of the hydroxyl groups on the silica particles, while BET and FT-IR were used to analyze the specific surface area and functional silane groups on the silica particles, respectively. In the sol-precipitation process, silanes that include various hydroxyl groups are formed as intermediates based on the hydrolysis and condensation of TEOS. Thus, NH3, as a basic catalyst initiating the nucleophilic substitution of TEOS, was found to accelerate the hydrolysis and increase the hydroxyl group content on the silica particles. Plus, the hydroxyl group content was also increased when increasing the concentrations of TEOS and water as the hydrolysis reactants. However, the hydroxyl group content was reduced when increasing the temperature, due to the promotion of condensation. Based on the weight loss of the particles according to the thermal analysis, the hydroxyl group content on the silica particles varied from 5.6–42.7OH/nm2 under the above reaction conditions. [Copyright &y& Elsevier]

The microwave characteristics and the microstructures of 0.88Al2O3–0.12TiO2 with various amounts of MgO–CaO–SiO2–Al2O3 (MCAS) glass sintered at different temperatures have been investigated. The sintering temperature can be lowered to 1300 °C by the addition of MCAS glass. The densities, dielectric constants (&epsiv;r) and quality values (Q×f) of the MCAS-added 0.88Al2O3–0.12TiO2 ceramics decrease with the increase of MCAS glass content. The temperature coefficients of the resonant frequency (τf) are shifted to more negative values as the MCAS content or the sintering temperatures increase. The change of the crystalline phases of Al2TiO5 phase and rutile-TiO2 phase has profound effects on the microwave dielectric properties of the MCAS-added Al2O3–TiO2 ceramics. As sintered at 1250 °C, 0.88Al2O3–0.12TiO2 ceramics with 2 wt.% MCAS glass addition exists a &epsiv;r value of 8.63, a Q×f value of 9578 and a τf value of +5 ppm/°C. [Copyright &y& Elsevier]

A periodic nano-porous surface on quartz crystal electrodes was carefully fabricated for increasing the mass-sensitive areas. Detailed porous structures were prepared by analyzing Au electrochemical reduction process of PS layer coated quartz crystals. The sensitivity measurement of the porous quartz crystals was performed with several traditional methods, and an optimized reduction time for higher sensitivity was determined. The frequency shift of the nano-porous quartz crystals showed 10 times bigger change with the same concentration of target solutions in self-assembly procedures. In the procedures, the freshly increased surface portion did not produce additional molecular slip-effects on the measured resonant resistance values, thus, the periodic porous chips showed another side merit for the mass sensor applications. We propose a possible use of the current porous surface as a platform for developing other high-performance sensors and analyses. A periodic nano-porous surface on quartz crystal electrodes was carefully fabricated for increasing the mass-sensitive areas. Detailed porous structures were prepared by analyzing Au electrochemical reduction process of PS layer coated quartz crystals. The sensitivity measurement of the porous quartz crystals was performed with several traditional methods, and an optimized reduction time for higher sensitivity was determined. The frequency shift of the nano-porous quartz crystals showed 10 times bigger change with the same concentration of target solutions in self-assembly procedures. In the procedures, the freshly increased surface portion did not produce additional molecular slip-effects on the measured resonant resistance values, thus, the periodic porous chips showed another side merit for the mass sensor applications. We propose a possible use of the current porous surface as a platform for developing other high-performance sensors and analyses. Image 1 • The mechanism for the PSB templated electrochemical gold deposition is clarified. • The increased gold areas did not show the sensitivity decrease done by the molecular-slip effect. • The self-assembly of 3-APTES showed 10-fold bigger frequency changes than a normal commercial quartz crystal. • A novel application of the fabricated chip was suggested for readers. [ABSTRACT FROM AUTHOR]

Abstract: A novel molecularly imprinted conducting polymer (MICP) system with porous thin films of electropolymerized polypyrrole (Ppy) derivatives was successfully developed to detect a specific target molecule (e.g. theophylline). The porous MICP films grown on gold pore arrays through cyclic voltammetry showed increased sensing response in detecting theophylline compared to a conventional planar MICP film due to its improved sensing capacity. [Copyright &y& Elsevier]

Abstract: Lavendustin A and hormothamnione were reported to exhibit cytotoxic effects on tumor cell lines. In the present studies, a series of chromone-based lavendustin analogs were synthesized as a simplified hybrid of hormothamnione and lavendustin A by the reductive-amination of formyl-chromone 5 with various amines followed by aminoalkylation. Most compounds synthesized showed significantly improved potencies compared to the standard compound 3 against most of cancer cell lines tested indicating that the removal of styryl group enhanced cancer cell growth inhibitory activities. Compound 4h and 4k showed the most potent inhibitory activities with GI50 values in the range of 6.01–9.92 μg/ml on A-549 and HCT-15 cells. [ABSTRACT FROM AUTHOR]

Objective: To evaluate serum adiponectin levels and organization into multimers in women with polycystic ovary syndrome (PCOS) and assess relationships between adiponectin, glucose tolerance, and insulin resistance.Design: In vivo and in vitro study.Setting: Outpatient clinic at university and Veterans hospitals in the United States and university laboratory.Patient(s): Thirty-one obese women with PCOS and six age- and body mass index (BMI)-matched normal cycling control subjects.Intervention(s): All subjects studied in the fasting state.Main Outcome Measure(s): A 75-g oral glucose tolerance test (OGTT), hyperinsulinemic/euglycemic clamp, circulating adiponectin levels, adipocyte adiponectin content, and organization of adiponectin into multimeric forms.Result(s): Whole body insulin action (glucose disposal rate, 5.61 +/- 2.90 vs. 8.79 +/- 0.81 mg/kg/min, PCOS and control) and adiponectin levels (9.5 +/- 0.7 7 vs. 17.4 +/- 1 microg/mL, PCOS vs. control) were significantly reduced in the subjects with PCOS. There were significant correlations between glucose tolerance, insulin action, and circulating adiponectin levels in all subjects. The content of adiponectin protein was reduced in subcutaneous adipocytes from subjects with PCOS (252 +/- 31 vs. 388 +/- 58 arbitrary units/10 microg protein). Subjects with PCOS had less of their circulating adiponectin organized into high molecular weight (HMW) multimeric complexes. Glucose-intolerant subjects with PCOS also had less intracellular HMW adiponectin.Conclusion(s): Both circulating adiponectin levels and the portion present as the most active HMW form are reduced in PCOS, with differences related to the degree of glucose intolerance and insulin resistance. [ABSTRACT FROM AUTHOR]

Abstract: 2-Styrylchromones, which are relatively scarce in nature, have been reported to possess potent cytotoxicities on KB cell line. Lavendustin A, a metabolite of Streptomyces griseolavendus, has been shown to inhibit a growth of A431 cell line. Accordingly, a series of compounds 3a–g having structural features of styrylchromones and lavendustin A were synthesized and evaluated for cytotoxicity using SRB assay on four tumor cell lines. Compounds 3a–g were synthesized by the condensation of 2-methylchromone derivative 7 with several aromatic aldehydes. Among synthesized, compound 3e showed the significant cytotoxic activity on HCT-15 cell line with IC50 values of 7.17 μg/ml indicating that lavendustin A derivatives containing 2-arylethenylchromone ring have a potential in anti-tumor application. [Copyright &y& Elsevier]

Abstract: Objective: Pravastatin has been reported to elevate circulating adiponectin levels in patients with various insulin resistant state, hypertension, coronary artery disease, and hypercholesterolemia. This study aimed to evaluate whether pravastatin increase serum total and high molecular weight adiponectin levels and improve insulin sensitivity in female patients with type 2 diabetes mellitus and hypercholesterolemia. Patients and design: This study was designed as a multicenter, double-blind, placebo-controlled, factorial randomized trial (placebo and pravastatin at 20 or 40 mg per day). A total of 73 female patients with type 2 diabetes and hypercholesterolemia were enrolled. Changes in total and high molecular weight (HMW) serum adiponectin levels, the ratio of HMW adiponectin to total adiponectin, insulin sensitivity measured by homeostasis model assessment of insulin resistance (HOMA-IR) and lipid profiles were evaluated after 16 weeks in each group. Results: Total cholesterol and low-density lipoprotein (LDL) cholesterol levels were significantly reduced after 16 weeks in the pravastatin 20 mg and 40 mg treatment groups compared with the placebo group (P = 0.008 and P = 0.004, respectively). However, there were no significant differences between the 20 mg and 40 mg pravastatin treatment groups in terms of total adiponectin and HMW adiponectin serum levels, as well as insulin sensitivity (P = 0.348 and P = 0.991). Conclusions: In female patients with type 2 diabetes and hypercholesterolemia, 16 weeks pravastatin therapy did not affect on serum total adiponectin or HMW adiponectin levels. [Copyright &y& Elsevier]

Abstract: In a series of field experiments, emissions of two major greenhouse gases (GHGs), methane (CH4) and carbon dioxide (CO2) were measured using a closed chamber technique in summer 2010 to evaluate the effects of solid beef cattle manure land application techniques. The treatments included a control (C: no manure), two manure application rates (40 and 80 T ha−1), and two injection layers (surface vs. subsurface (5 cm)): (1) 40 T ha−1 on surface (S40), (2) 80 T ha−1 on surface (S80), (3) 40 T ha−1 at subsurface (D40), and (4) 80 T ha−1 at subsurface (D80)). The exchange patterns of CH4 and CO2 in the control were variable and showed both emission and deposition. However, only emissions were seen in the manure treatments. Emissions of CH4 were seen systematically on the ascending order of 5.35 (C), 59.3 (S40), 68.7 (D40), 188 (S80), and 208 μg m−2 h−1 (D80), while those of CO2 also showed a similar trend: 12.9 (C), 37.6 (S40), 55.8 (D40), 82.4 (S80), and 95.4 mg m−2 h−1 (D80). The overall results of our study suggest that the emissions of CH4 and CO2 are affected most noticeably by the differences in the amount of manure application. [Copyright &y& Elsevier]

Abstract: Background: Induced pluripotent stem (iPS) cells allow derivation of autologous differentiated cells for cell therapy. The purpose of this study was to compare the cardiac differentiation potential of mouse iPS cells with embryonic stem (ES) cells and demonstrate that they could produce functional cardiomyocytes. Methods: iPS cells were prepared from mouse embryonic fibroblasts by lentiviral mediated expression of four transcription factors (Oct4/Sox2/Klf4/C-myc). To induce cardiac cell differentiation, iPS-S-6 or D3-ES cells were induced to form embryoid bodies (EBs) using a two-medium culture protocol, then plated onto gelatin-coated plates and maintained in DMEM. Results: Following classification of the generation periods of contracting EBs into early (d8–d11), middle (d12–d15) and late (d16–20), iPS cells in the early period exhibited characteristics similar to ES cells. In iPS cells from the middle period group, the ratio of contracting EBs was significantly increased compared to ES cells, and the difference persisted in cells from the late period group (p<0.05). The percentage of contracting EBs formed from iPS and ES cells were 44.8% and 33.3%, respectively. In addition, iPS cell-derived cardiomyocytes exhibited mRNA expression of cardiac mesoderm markers such as GATA4 and NKX2.5, and cardiomyocyte markers such as α1s, α1c, α-MHC, β-MHC, Cx40, TnI, TnT, ANF and Hey2. Single cardiomyocytes exhibited typical cross-striated myofibrillar organization, and electrophysiological studies revealed functional cardiac-specific voltage-gated Na+, Ca2+ and K+ channels. Conclusions: These results demonstrate that functional cardiomyocytes can be generated from iPS cells, and suggest that these cells may be useful for the treatment of cardiovascular disease. [Copyright &y& Elsevier]

Abstract: The drown-out crystallization of sodium chloride is conducted on a DNA-modified quartz crystal microbalance (QCM). To investigate the crystallization behavior of NaCl on a DNA template, a thiol-modified DNA oligomer is self-assembled on a gold electrode of QCM. The resonant frequency shift and resonant resistance of the DNA-modified QCM are measured with the continuous injection of ethanol in the NaCl saturated solution, and compared with those of a bare QCM without any modification. F–R diagram is interpreted to analyze a detailed mechanism of the QCM response change for the crystallization. An atomic force microscope (AFM) technique is also used to confirm the procedure of the NaCl crystallization on the DNA template. From these results, it is found that the QCM sensor system could be applied to monitor the NaCl crystallization in the aqueous solution, and to detect a super-saturation point or degree. [Copyright &y& Elsevier]

Abstract: We show a new fabrication technique of a molecular order thin film utilizing a simple molecular diffusion method. Hydrophilic polymers of different molecular weights are used for the examination. The mechanism and the standard procedure of the technique are analyzed by a quartz crystal microbalance and an atomic force microscope. The results show the molecularly flat nanostructure of the final film can be fabricated by the technique. In our experimental condition, lower molecular weighted hydrophilic polymers (M w<10,000) such as PEG, PVA and PAA are spontaneously self-assembled on mica and gold surfaces. We believe the technique can be useful in many other surface-related studies and applications. [Copyright &y& Elsevier]

Different amounts of MgO–CaO–SiO2–Al2O3 (MCAS) glass content are used as the sintering aid of 0.84(mol%)Al2O3–0.16(mol%)TiO2 composition. The sintering characteristics, the crystal structures, and the microwave characteristics of MCAS glass-added 0.84Al2O3–0.16TiO2 ceramics have been investigated under the sintering temperatures of 1200–1350 °C. During the sintering process, the TiO2 and Al2O3 will form the Al2TiO5 phase. The crystal intensity of Al2TiO5 phase increases and that of TiO2 phase decreases with the increase of sintering temperature. In this study, the MCAS glass content and sintering temperature have large effects on the sintering and microwave dielectric characteristics of MCAS glass-added 0.84Al2O3–0.16TiO2 ceramics. [Copyright &y& Elsevier]

[Display omitted] Our previous research showed that N -carboxy-phenylsulfonyl hydrazide (scaffold A) could reduce LPS-stimulated PGE 2 levels in RAW 264.7 macrophage cells by an inhibition of mPGES-1 enzyme. However, a number of scaffold A derivatives showed the drawbacks such as the formation of regioisomers and poor liver metabolic stability. In order to overcome these synthetic and metabolic problems, therefore, we decided to replace N -carboxy-phenylsulfonyl hydrazide (scaffold A) with N -carboxy-phenylsulfonamide (scaffold B) or N -amido-phenylsulfonamide frameworks (scaffold C) as a bioisosteric replacement. Among them, MPO-0186 (scaffold C) inhibited the production of PGE 2 (IC 50 : 0.24 μM) in A549 cells via inhibition of mPGES-1 (IC 50 : 0.49 μM in a cell-free assay) and was found to be approximately 9- and 8-fold more potent than MK-886 as a reference inhibitor, respectively. A molecular docking study theoretically suggests that MPO-0186 could inhibit PGE 2 production by blocking the PGH 2 binding site of mPGES-1 enzyme. Furthermore, MPO-0186 demonstrated good liver metabolic stability and no significant inhibition observed in clinically relevant CYP isoforms except CYP2C19. This result provides a potential starting point for the development of selective and potent mPGES-1 inhibitor with a novel scaffold. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of calcium ionophore on the fertilization rate of a patient with normozoospermia who nonetheless exhibited a low fertilization rate in intracytoplasmic sperm injection (ICSI).Design: Case report.Setting: In vitro fertilization center.Patient(s): A male patient whose sperm, though diagnosed as normal by semen analysis, exhibited a severely low fertilization rate in ICSI cycles.Intervention(s): Oocytes were activated by calcium ionophore after ICSI.Main outcome measure(s): Fertilization rate after oocyte activation; ultrastructure and protein expression of the patient''s sperm.Result(s): The fertilization rate of oocytes activated with calcium ionophore (12 of 15, 80.0%) was higher than that of the nonactivated oocytes (4 of 16, 25.0%). Four embryos derived from the activated oocytes were transferred, resulting in a twin pregnancy. Further investigation revealed abnormalities in the patient''s sperm: many nuclear vacuoles were observed and the expression of some proteins was absent.Conclusion(s): Oocyte activation with calcium ionophore was effective at increasing the fertilization rate of dysfunctional sperm characterized by ultrastructural and protein expression anomalies. [Copyright &y& Elsevier]

In order to investigate dynamic properties of polypyrrole (Ppy) thin films in various electrolyte solutions, NaCl, NaClO4, NaNO3, NaDS, LiClO4, KClO4, resonant frequency and resistance were measured through electrical polymerization process using a quartz crystal analyzer (QCA). The surface structure was observed by using atomic force microscopy (AFM). A diagram of the resonant frequency and resistance (F-R diagram) was used to interpret the results and compared with AFM photograph. When the Ppy film is polymerized onto the AT-cut quartz electrode crystal, it behaves as a rigid elastic layer at the initial stage. Then, it turns into a viscoelastic layer as polymerization. This is due to the penetration of electrolytes into the film. The size, mass and mobility of the hydrated cation and anion of the electrolyte affected the degree of the viscoelastic change of the polypyrrole thin films. [Copyright &y& Elsevier]