Novel composite meshes to evaluate their structural property and in vivo biocompatibility for tissue repair

404-410Composite meshes of different types have been prepared and used for tissue repair in pelvic floor disorder. An interlocking texture mesh (inter-mesh) and a membrane coated mesh (electro-mesh) have been used based on their structural property and biocompatibility. The proportion of degradation material in inter-mesh (69.6%) is found extremely higher than that of electro-mesh (3.22%), thus leading to higher product weight (65.50±2.31 g/m2) and thickness (0.500±0.025 mm). After 4 weeks of implantation in animal experiment, inter-mesh with surrounding tissues is observed to have higher breaking strength in tensile behavoir and better flexibility. Tissues on inter-mesh are found to grow faster with larger thickness (0.76±0.033 mm). The surface area loss of inter-mesh (2.49±0.25%) is much less than that of electro-mesh (7.49±0.63 %) within the first 2 weeks of implantation. However, the material’s degradation is accelerated after 2 weeks, leading to a higher shrinkage of 13.12±1.48 %

Novel composite meshes to evaluate their structural property and in vivo biocompatibility for tissue repair

Composite meshes of different types have been prepared and used for tissue repair in pelvic floor disorder. An interlocking texture mesh (inter-mesh) and a membrane coated mesh (electro-mesh) have been used based on their structural property and biocompatibility. The proportion of degradation material in inter-mesh (69.6%) is found extremely higher than that of electro-mesh (3.22%), thus leading to higher product weight (65.50±2.31 g/m2) and thickness (0.500±0.025 mm). After 4 weeks of implantation in animal experiment, inter-mesh with surrounding tissues is observed to have higher breaking strength in tensile behavoir and better flexibility. Tissues on inter-mesh are found to grow faster with larger thickness (0.76±0.033 mm). The surface area loss of inter-mesh (2.49±0.25%) is much less than that of electro-mesh (7.49±0.63 %) within the first 2 weeks of implantation. However, the material’s degradation is accelerated after 2 weeks, leading to a higher shrinkage of 13.12±1.48 %

Novel Tet(L) Efflux Pump Variants Conferring Resistance to Tigecycline and Eravacycline in Staphylococcus Spp.

Tigecycline is regarded as one of the few important last-resort antibiotics to treat complicated skin and intra-abdominal infections. Members of the genus Staphylococcus are zoonotic pathogens and pose a serious threat to public health. Tigecycline resistance in this species appears to be a rare phenomenon, and the mechanisms underlying tigecycline resistance have not been fully elucidated. Here, we report two novel variants of the tet(L) gene in Staphylococcus spp. from swine in China, designed as tet(L)F58L and tet(L)A117V. The tet(L)F58L was located within a 18,720 bp chromosomal multidrug resistance gene cluster flanked by two copies of IS257 in Staphylococcus cohnii 11-B-312, while the tet(L)A117V was located on a 6,292 bp plasmid in S. haemolyticus 11-B-93, which could be transferred to S. aureus by electrotransformation. Cloning of each of the two tet(L) variants into S. aureus RN4220 showed 16- or 8-fold increases in the minimal inhibition concentrations (MICs), which can fully confer the resistance to tigecycline (MICs from 0.125 to 2 mg/liter) and eravacycline (MICs from 0.125 to 1 or 2 mg/liter), but no increase in the MICs of omadacycline, compared with the MICs of the recipient strain S. aureus RN4220. In the in vivo murine sepsis and in the murine pneumonia models, an increase in CFU of S. aureus 29213_pT93 carrying the tet(L)A117V was seen despite tigecycline treatment. This observation suggests that the tet(L)A117V and its associated gene product compromise the efficacy of tigecycline treatment in vivo and may lead to clinical treatment failure. Our finding, that novel Tet(L) efflux pump variants which confer tigecycline and eravacycline resistance have been identified in Staphylococcus spp., requires urgent attention. IMPORTANCE Tigecycline and eravacycline are both important last-resort broad spectrum antimicrobial agents. The presence of novel Tet(L) efflux pump variants conferring the resistance to tigecycline and eravacycline in Staphylococcus spp. and its potential transmission to S. aureus will compromise the efficacy of tigecycline and eravacycline treatment for S. aureus associated infection in vivo and may lead to clinical treatment failure

The influence of preincubation time of prepared sperm before IVF on fertilization, embryo developmental competence and the reproductive outcomes

Objectives: It has been provided that if incubation time of prepared sperm can affect sperm motility and DNA fragment, but little is known about the influence of sperm preincubation time (SI) on the sperm’s fertilizing ability, subsequent embryonic development and pregnancy outcomes in in vitro fertilization (IVF). The aim of this study was to explore the association of SI with fertilization rate, embryo development and clinical outcomes in IVF, further, to find an optimal preincubation time for prepared sperm before insemination in IVF. Material and methods: This retrospective cohort study included a total of 1453 infertile couples undergoing IVF in our center performed from January 2016 to January 2019. Sperm were preincubated at 37℃ 6% CO2 for different times before insemination. Preincubation time associated with fertilization rate (FR), 2PN rate, D3 good quality embryo rate, fresh embryo implantation rate (IR), blastocyst formation rate, cumulative pregnancy rate (CPR), cumulative ongoing pregnancy rate (COPR), cumulative live birth rate (CLBR), newborn health and gender ratio were analyzed by chi-square analysis. Results: FR and 2PN rate of SI more than four hours SI groups (> 4 h SI group) decreased significantly compared with other SI groups (p < 0.01). There were no significant differences of the D3 high quality embryo rate among five SI groups. The blastocyst formation rate of  > 4 h SI group was significantly lower than that of 2–3 h SI group (45.5% vs 56.1%, p < 0.05); and 1–2 h SI group also had significant difference with 2–3 h and 3–4 h SI group (48.9% vs 56.1% and 54.6%, p < 0.05). There were a significant decrease of fresh IR and CPR in ≤1 h SI group compared with 1–2 h SI group (19.6% vs. 38.0%, p < 0.05; 62.7% vs 73.7%, p < 0.05); ≤ 1 h SI group also have the lowest CLBR (45.6%), it had statistic differences with 1–2 SI group and 3–4 SI group (45.6% vs 63.2%, p < 0.01; 45.6% vs 61.2%, p < 0.05). Conclusions: The sperm preincubated time at 37℃ 6% CO2 before insemination could influence sperm fertilizing ability, blastocyst formation, embryo implantation and CLBR in IVF cycles. The best time for prepared sperm preincubation at 37℃ is one to four hours before insemination in IVF

In Situ Study the Dynamics of Blade-Coated All-Polymer Bulk Heterojunction Formation and Impact on Photovoltaic Performance of Solar Cells

All-polymer solar cells (all-PSCs) have achieved impressive progress by employing acceptors polymerized from well performing small-molecule non-fullerene acceptors. Herein, the device performance and morphology evolution in blade-coated all-PSCs based on PBDBT:PF5–Y5 blends prepared from two different solvents, chlorobenzene (CB), and ortho-xylene (o-XY) are studied. The absorption spectra in CB solution indicate more ordered conformation for PF5–Y5. The drying process of PBDBT:PF5–Y5 blends is monitored by in situ multifunctional spectroscopy and the final film morphology is characterized with ex situ techniques. Finer-mixed donor/acceptor nanostructures are obtained in CB-cast film than that in o-XY-cast ones, corresponding to more efficient charge generation in the solar cells. More importantly, the conformation of polymers in solution determines the overall film morphology and the device performance. The relatively more ordered structure in CB-cast films is beneficial for charge transport and reduced non-radiative energy loss. Therefore, to achieve high-performance all-PSCs with small energy loss, it is crucial to gain favorable aggregation in the initial stage in solution

Bayesian multimodel estimation of global terrestrial latent heat flux from eddy covariance, meteorological, and satellite observations

Accurate estimation of the satellite-based global terrestrial latent heat flux (LE) at high spatial and temporal scales remains a major challenge. In this study, we introduce a Bayesian model averaging (BMA) method to improve satellite-based global terrestrial LE estimation by merging five process-based algorithms. These are the Moderate Resolution Imaging Spectroradiometer (MODIS) LE product algorithm, the revised remote-sensing-based Penman-Monteith LE algorithm, the Priestley-Taylor-based LE algorithm, the modified satellite-based Priestley-Taylor LE algorithm, and the semi-empirical Penman LE algorithm. We validated the BMA method using data for 2000–2009 and by comparison with a simple model averaging (SA) method and five process-based algorithms. Validation data were collected for 240 globally distributed eddy covariance tower sites provided by FLUXNET projects. The validation results demonstrate that the five process-based algorithms used have variable uncertainty and the BMA method enhances the daily LE estimates, with smaller root mean square errors (RMSEs) than the SA method and the individual algorithms driven by tower-specific meteorology and Modern Era Retrospective Analysis for Research and Applications (MERRA) meteorological data provided by the NASA Global Modeling and Assimilation Office (GMAO), respectively. The average RMSE for the BMA method driven by daily tower-specific meteorology decreased by more than 5 W/m2 for crop and grass sites, and by more than 6 W/m2 for forest, shrub, and savanna sites. The average coefficients of determination (R2) increased by approximately 0.05 for most sites. To test the BMA method for regional mapping, we applied it for MODIS data and GMAO-MERRA meteorology to map annual global terrestrial LE averaged over 2001–2004 for spatial resolution of 0.05°. The BMA method provides a basis for generating a long-term global terrestrial LE product for characterizing global energy, hydrological, and carbon cycles

CT-Based Risk Factors for Mortality of Patients With COVID-19 Pneumonia in Wuhan, China: A Retrospective Study

Purpose: Computed tomography (CT) characteristics associated with critical outcomes of patients with coronavirus disease 2019 (COVID-19) have been reported. However, CT risk factors for mortality have not been directly reported. We aim to determine the CT-based quantitative predictors for COVID-19 mortality.Methods: In this retrospective study, laboratory-confirmed COVID-19 patients at Wuhan Central Hospital between December 9, 2019, and March 19, 2020, were included. A novel prognostic biomarker, V-HU score, depicting the volume (V) of total pneumonia infection and the average Hounsfield unit (HU) of consolidation areas was automatically quantified from CT by an artificial intelligence (AI) system. Cox proportional hazards models were used to investigate risk factors for mortality.Results: The study included 238 patients (women 136/238, 57%; median age, 65 years, IQR 51–74 years), 126 of whom were survivors. The V-HU score was an independent predictor (hazard ratio [HR] 2.78, 95% confidence interval [CI] 1.50–5.17; p = 0.001) after adjusting for several COVID-19 prognostic indicators significant in univariable analysis. The prognostic performance of the model containing clinical and outpatient laboratory factors was improved by integrating the V-HU score (c-index: 0.695 vs. 0.728; p < 0.001). Older patients (age ≥ 65 years; HR 3.56, 95% CI 1.64–7.71; p < 0.001) and younger patients (age < 65 years; HR 4.60, 95% CI 1.92–10.99; p < 0.001) could be further risk-stratified by the V-HU score.Conclusions: A combination of an increased volume of total pneumonia infection and high HU value of consolidation areas showed a strong correlation to COVID-19 mortality, as determined by AI quantified CT

Revealing the crystalline packing structure of Y6 in the active layer of organic solar cells: the critical role of solvent additives

The bulk heterojunction (BHJ) morphology of photovoltaic materials is crucial to the fundamental optoelectronic properties of organic solar cells (OSCs). However, in the photoactive layer, the intrinsic crystalline packing structure of Y6, currently the hallmark molecule among Y-series non-fullerene acceptors (NFAs), has not been unambiguously determined. Here, employing grazing-incidence wide-angle X-ray scattering (GIWAXS), we managed to uncover the intrinsic crystalline packing structure of Y6 in the BHJ active layer of OSCs, which is found to be different from its single-crystal structure reported previously. Moreover, we find that solvent additive 1-chloronaphthalene (CN) can induce highly ordered packing of Y6 in BHJ thin films. With the help of atomistic molecular dynamics simulations, it is revealed that π-π interactions generally exist between naphthalene derivatives and IC terminals of Y6 analogues, which would essentially improve their long-range ordering. Our work reveals the intrinsic crystalline packing structure of Y6 in the BHJ active layer as well as its crystallization mechanism in thin films, thus providing direct correlations between this crystalline packing and the device characteristics and photophysical properties.Knut och Alice Wallenbergs StiftelseImmediate accessThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data