An injectable collagen peptide-based hydrogel with desirable antibacterial, self-healing and wound-healing properties based on multiple-dynamic crosslinking.

Conventional collagen-based hydrogels as wound dressing materials are usually lack of antibacterial activity and easily broken when encountering external forces. In this work, we developed a collagen peptide-based hydrogel as a wound dressing, which was composed of adipic acid dihydrazide functionalized collagen peptide (Col-ADH), oxidized dextran (ODex), polyvinyl alcohol (PVA) and borax via multiple-dynamic reversible bonds (acylhydrazone, amine, borate ester and hydrogen bonds). The injectable hydrogel exhibited satisfactory self-healing ability, antibacterial activity, mechanical strength, as well as good biocompatibility and biodegradability. In vivo experiments demonstrated the rapid hemostasis, accelerated cell migration, and promoted wound healing capacities of the hydrogel. These results indicate that the multifunctional collagen peptide-based hydrogel has great potentials in the field of wound dressings.

Organocatalytic atroposelective synthesis of axially chiral N,N'-pyrrolylindoles via de novo indole formation.

The first organocatalytic atroposelective synthesis of axially chiral N,N'-pyrrolylindoles based on o-alkynylanilines was successfully established via de novo indole formation catalyzed by chiral phosphoric acid (CPA). This new synthetic strategy introduced CPA-catalyzed asymmetric 5-endo-dig cyclization of new well-designed o-alkynylanilines containing a pyrrolyl unit, resulting in a wide range of axially chiral N,N'-pyrrolylindoles in high yields with exclusive regioselectivity and excellent enantioselectivity (up to 99% yield, >20 : 1 rr, 95 : 5 er). Considering the potential biological significance of N-N atropisomers, preliminary biological activity studies were performed and revealed that these structurally important N,N'-pyrrolylindoles had a low IC50 value with promising impressive cytotoxicity against several kinds of cancer cell lines. DFT studies reveal that the N-nucleophilic cyclization mediated by CPA is the rate- and stereo-determining step, in which ligand-substrate dispersion interactions facilitate the axial chirality of the target products.

Outcomes Following Transcatheter Aortic Valve Replacement for Aortic Stenosis in Patients With Type 0 Bicuspid, Type 1 Bicuspid, and Tricuspid Aortic Valves.

BACKGROUND: Data concerning the outcomes of transcatheter aortic valve replacement in type 0 bicuspid aortic stenosis (AS) are scarce. The study aims to compare the outcomes of transcatheter aortic valve replacement for AS in patients with type 0 bicuspid, type 1 bicuspid, and tricuspid aortic valve anatomy. METHODS: We enrolled consecutive patients undergoing transcatheter aortic valve replacement for severe AS between 2012 and 2022 in this single-center retrospective cohort study. The primary outcome was mortality, while secondary outcomes included in-hospital complications such as stroke and pacemaker implantation and transcatheter heart valve hemodynamic performance. RESULTS: The number of patients with AS with type 0 bicuspid, type 1 bicuspid, and tricuspid aortic valve anatomy was 328, 302, and 642, respectively. Self-expanding transcatheter heart valves were used in the majority of patients (n=1160; 91.4%). In the matched population, differences in mortality (30 days: 4.2% versus 1.7% versus 1.7%, Poverall=0.522; 1 year: 10% versus 2.3% versus 6.2%, Poverall=0.099) and all stroke (30 days: 1.0% versus 0.9% versus 0.0%, Poverall=0.765; 1 year: 1.4% versus 1.6% versus 1.3%, Poverall=NS) were nonsignificant, and the incidence of overall in-hospital complications was comparable among groups. Ascending aortic diameter was the single predictor of 1-year mortality in type 0 bicuspid patients (hazard ratio, 1.59 [95% CI, 1.03-2.44]; P=0.035). The proportion of patients with a mean residual gradient ≥20 mm Hg was the highest in those with type 0 bicuspid anatomy, although the need for permanent pacemaker implantation was the lowest in this group. CONCLUSIONS: Major clinical outcomes of transcatheter aortic valve replacement for AS in patients with type 0 bicuspid, type 1 bicuspid, and tricuspid aortic valve anatomy are equivalent at short- and mid-term follow-up. These observations merit further exploration in prospective international registries and randomized controlled trials.

Interpretable machine-learning model for Predicting the Convalescent COVID-19 patients with pulmonary diffusing capacity impairment.

INTRODUCTION: The COVID-19 patients in the convalescent stage noticeably have pulmonary diffusing capacity impairment (PDCI). The pulmonary diffusing capacity is a frequently-used indicator of the COVID-19 survivors' prognosis of pulmonary function, but the current studies focusing on prediction of the pulmonary diffusing capacity of these people are limited. The aim of this study was to develop and validate a machine learning (ML) model for predicting PDCI in the COVID-19 patients using routinely available clinical data, thus assisting the clinical diagnosis. METHODS: Collected from a follow-up study from August to September 2021 of 221 hospitalized survivors of COVID-19 18 months after discharge from Wuhan, including the demographic characteristics and clinical examination, the data in this study were randomly separated into a training (80%) data set and a validation (20%) data set. Six popular machine learning models were developed to predict the pulmonary diffusing capacity of patients infected with COVID-19 in the recovery stage. The performance indicators of the model included area under the curve (AUC), Accuracy, Recall, Precision, Positive Predictive Value(PPV), Negative Predictive Value (NPV) and F1. The model with the optimum performance was defined as the optimal model, which was further employed in the interpretability analysis. The MAHAKIL method was utilized to balance the data and optimize the balance of sample distribution, while the RFECV method for feature selection was utilized to select combined features more favorable to machine learning. RESULTS: A total of 221 COVID-19 survivors were recruited in this study after discharge from hospitals in Wuhan. Of these participants, 117 (52.94%) were female, with a median age of 58.2 years (standard deviation (SD) = 12). After feature selection, 31 of the 37 clinical factors were finally selected for use in constructing the model. Among the six tested ML models, the best performance was accomplished in the XGBoost model, with an AUC of 0.755 and an accuracy of 78.01% after experimental verification. The SHAPELY Additive explanations (SHAP) summary analysis exhibited that hemoglobin (Hb), maximal voluntary ventilation (MVV), severity of illness, platelet (PLT), Uric Acid (UA) and blood urea nitrogen (BUN) were the top six most important factors affecting the XGBoost model decision-making. CONCLUSION: The XGBoost model reported here showed a good prognostic prediction ability for PDCI of COVID-19 survivors during the recovery period. Among the interpretation methods based on the importance of SHAP values, Hb and MVV contributed the most to the prediction of PDCI outcomes of COVID-19 survivors in the recovery period.

Bioelectret poly(lactic acid) membranes with simultaneously enhanced physical interception and electrostatic adsorption of airborne PM0.3.

Traditional polymeric fibrous membranes have been extensively used to reduce the health risks caused by airborne particulate matter (PM), leading to the dramatically increasing pollution of plastics and microplastics. Although great efforts have been made to develop poly(lactic acid) (PLA)-based membrane filters, they are frequently dwarfed by their relatively poor electret properties and electrostatic adsorptive mechanisms. To resolve this dilemma, a bioelectret approach was proposed in this work, strategically involving the bioinspired adhesion of dielectric hydroxyapatite nanowhiskers as a biodegradable electret to promote the polarization properties of PLA microfibrous membranes. In addition to significant improvements in tensile properties, the incorporation of hydroxyapatite bioelectret (HABE) enabled remarkable increase in the removal efficiencies of ultrafine PM0.3 in a high-voltage electrostatic field (10 and 25 kV). This was exemplified by the largely increased filtering performance (69.75%, 23.1 Pa) for PLA membranes loaded with 10 wt% HABE at the normal airflow rate (32 L/min) compared to the pristine PLA counterpart (32.89%, 7.2 Pa). Although the filtration efficiency of PM0.3 for the counterpart dramatically decreased to 21.6% at 85 L/min, the increment was maintained at nearly 196% for the bioelectret PLA, while an ultralow pressure drop (74.5 Pa) and high humidity resistance (RH 80%) were achieved. The unusual property combination were ascribed to the HABE-enabled realization of multiple filtration mechanisms, including the simultaneous enhancement of physical interception and electrostatic adsorption. The significant filtration applications, unattainable with conventional electret membranes, demonstrate the bioelectret PLA as a promising biodegradable platform that allows high filtration properties and humidity resistance.

Concomitant aortic regurgitation predicts better left ventricular reverse remodeling after transcatheter aortic valve replacement.

BACKGROUND: We aim to determine predictors of inadequate left ventricular mass index (LVMi) regression at mid-term after transcatheter aortic valve replacement (TAVR), including the potential role of epicardial adipose tissue (EAT). METHODS: We retrospectively reviewed patients with both echocardiographic assessments and multi-slice computed tomography (MSCT) obtained one year after TAVR. The change of LVMi, the volume and the average CT attenuation of EAT from baseline to one-year follow-up was calculated. Patients were divided into two groups by the percentage change of LVMi at a cut-off of 15%. RESULTS: A total of 152 patients were included with a median age of 74 years (interquartile range [IQR] 69-78 years) and 56.6% being male. LVMi decreased (P < 0.0001) while EAT volume increased and the average CT attenuation decreased (both P < 0.0001) at one year. Baseline atrial fibrillation (P = 0.042), mitral regurgitation ≥ mild (P = 0.006), aortic regurgitation (AR) > mild (P = 0.001) and the change in the average CT attenuation of EAT (P = 0.026) were different between the decrease of LVMi ≥ 15% and < 15%. AR > mild at baseline was the only statistically significant predictor of a decrease of LVMi < 15% at one year (OR 0.33, 95% CI: 0.13 to 0.84, P = 0.021) in multivariate regression. CONCLUSIONS: Concomitant more-than-mild AR might predict better left ventricular reverse remodeling regression after TAVR.

Ion recognition properties of 2,2'-bibenzimidazole regulated by ammonium-modified pillar[5]arenes.

With the increasing issues of environmental degradation and health problem, the selective detection of toxic ions has attracted considerable attention from researchers. Chemical fluorescent sensors with the advantages of facile operation, high sensitivity, rapid response, and easy visualization are emerging as powerful detection tools towards ions. However, the selective recognition of ions is always hindered by the presence of other interfering substances. Herein, we show that supramolecular host-guest interaction based on a pillar[5]arene provides a new opportunity to regulate the ionic recognition properties of guest molecules. A pillar[5]arene-based host-guest complex HG was constructed through the host-guest interaction between ammonium functionalized pillar[5]arene (HAP5) and 2,2'-bibenzimidazole (G). The host-gust complex HG can realize the successive, highly selective, and sensitive detection of specific ions. It was found that only in the presence of HAP5, the sensitivity towards cations was evidently enhanced, and selective successive recognition for I- and HSO4- was achieved. Those results indicate that the introduction of HAP5 can effectively improve the ion recognition performance of 2,2'-bibenzimidazole, so it is a feasible strategy using supramolecular host-guest interaction to regulate the ionic recognition properties of guest molecules.

UV-protective and high-transparency poly(lactic acid) biocomposites for ecofriendly packaging of perishable fruits.

The past decades have witnessed the archetypal shift from petroleum-based to bioplastics including poly(lactic acid) (PLA) for multifunctional packaging. Here we disclose a microwave-assisted functionalization (MAF) approach to functionalize wood fibers (FWFs) at minute level and high yields (approaching 99 %), conferring high affinity to PLA matrix and significant promotion of mechanical properties. By incorporating of 10 wt% FWFs, the tensile strength and toughness of PLA composite films were elevated to 54.5 MPa and 1.6 MJ/m3, increasing nearly 28 % and over 45 % compared to those of the counterpart loaded pristine wood fibers (PWFs), respectively. It is of significance to note the FWF-enabled unique optical properties for PLA, as exemplified by approximately 100 % UV-blocking ratio (UVR) in the whole UV region with the addition of 20 wt% FWFs. By contrast, the UVR values of PWF-filled PLA (5 %-20 %) gradually decreased as the fiber contents increased, mainly ascribed to the UV reflection at the poorly bonded interfaces and relatively inferior functionality of PWFs. This distinction allowed us to fabricate UV-barrier packaging for preservation of fresh fruits, which were perishable under the UV light of sunshine. The impressive mechanical robustness and high UVR, may prompt affordable and ecofriendly PLA/FWF composites appropriate for packaging.

Nonlinear Optical Properties of Pyrene Derivatives Based on a Donor-Acceptor Structure and Its Polyurethane Composites.

Two pyrenyl Schiff base derivatives with π conjugated structures (B2 and B3) were designed and synthesized. Then, B2 and B3 were added into polyurethane to obtain doped and bonded polyurethane nonlinear optical materials (B2/PU and B3/PU), respectively. The synthesized B2, B3, and polyurethane nonlinear optical materials were tested by a nanosecond (ns) and picosecond (ps) pulse Z-scan at a 532 nm wavelength. Due to the two-photon absorption-induced excited state absorption (TPA-ESA), B2, B3, and polyurethane nonlinear optical materials show reverse saturable absorption (RSA). From a quantum chemistry calculation, it can be concluded that the RSA of B2 and B3 comes from the large π conjugated system and intramolecular charge transfer. Furthermore, B2, B3, and the polyurethane nonlinear optical materials show good optical limiting. B2/PU and B3/PU not only have excellent nonlinear optical properties but also have good transmittance, thermal stability, and processability of polyurethane materials. The combination of pyrenyl Schiff base derivatives and polyurethane materials greatly improves the application of nonlinear small molecules in the field of optical limiting and all-optical switching.

Sex Difference in Outcomes Following Transcatheter Aortic Valve Replacement in Bicuspid Aortic Stenosis.

BACKGROUND: It is unknown whether the sex difference whereby female transcatheter aortic valve replacement (TAVR) candidates had a lower risk profile, a higher incidence of in-hospital complications, but more favorable short- and long-term survival observed in tricuspid cohorts undergoing TAVR would persist in patients with bicuspid aortic valves (BAVs). OBJECTIVES: The aim of this study was to reexamine the impact of sex on outcomes following TAVR in patients with BAVs. METHODS: In this single-center study, patients with BAVs undergoing TAVR for severe aortic stenosis from 2012 to 2021 were retrospectively included. Baseline characteristics, aortic root anatomy, and in-hospital and 1-year valve hemodynamic status and survival were compared between sexes. RESULTS: A total of 510 patients with BAVs were included. At baseline, women presented with fewer comorbidities. Men had a greater proportion of Sievers type 1 BAV, higher calcium volumes (549.2 ± 408.4 mm3 vs 920.8 ± 654.3 mm3; P < 0.001), and larger aortic root structures. Women experienced more vascular complications (12.9% vs 4.9%; P = 0.002) and bleeding (11.1% vs 5.3%; P = 0.019) and higher residual gradients (16.9 ± 7.7 mm Hg vs 13.2 ± 6.4 mm Hg; P < 0.001), while men were more likely to undergo second valve implantations during index TAVR (6.3% vs 15.9%; P = 0.001). Death at 1 year was not significantly different between sexes (HR: 1.15; 95% CI: 0.56-2.35; P = 0.70). Bleeding (adjusted HR: 4.62; 95% CI: 1.51-14.12; P = 0.007) was the single independent predictor of 1-year death for women. CONCLUSIONS: In patients with BAVs undergoing TAVR, women presented with fewer comorbidities, while men had a greater proportion of type 1 BAV, more calcification, and larger aortic roots. In-hospital outcomes favored men, with fewer complications except for the need for second valve implantation, but 1-year survival was comparable between sexes.

Pea pod-mimicking hydroxyapatite nanowhisker-reinforced poly(lactic acid) composites with bone-like strength.

The anisotropic hierarchical structures of naturally derived materials have offered useful design principles for the fabrication of high-strength and functional materials. Herein, we unraveled a structure-by-bionics approach to construction of pea pod-mimicking architecture for poly(lactic acid) (PLA) composites impregnated with hydroxyapatite nanowhiskers (HANWs). The HANWs (length of 80-120 nm, diameter of ~30 nm) were customized using microwave-assisted aqueous biomineralization at minute level, which were incorporated into PLA microfibers by electrospinning with filler loadings of 10-30 wt%. The membranes comprising HANW-modified PLA microfibers were stacked and structured into composite films, strategically involving high-pressure compression at a relatively low temperature to impart the confined structuring mechanisms. It thus allowed partial melting and thinning of PLA microfibers into nanofibers, onto which the discrete HANWs were tightly adhered and embedded, showing distinguished architectural configurations identical with pea pod. More importantly, the mechanical properties and bioactivity were remarkably promoted, as demonstrated by the increments of over 54 % and nearly 72 % for the yield strength and elastic modulus (71.6 and 2547 MPa) of the structured composite loaded 30 wt% HANWs compared to those of pure PLA (46.4 and 1484 MPa), as accompanied by significant improvements in the bioactivity to nucleate and create apatite entities in mineral solution. The unusual combination of excellent biological characteristics and bone-like mechanical elasticity and extensibility make the structured PLA composites promising for guided bone/tissue regeneration therapy.

Patients With Bicuspid Aortic Stenosis Undergoing Transcatheter Aortic Valve Replacement: A Systematic Review and Meta-Analysis.

Objective: We sought to conduct a systematic review and meta-analysis of clinical adverse events in patients undergoing transcatheter aortic valve replacement (TAVR) with bicuspid aortic valve (BAV) vs. tricuspid aortic valve (TAV) anatomy and the efficacy of balloon-expandable (BE) vs. self-expanding (SE) valves in the BAV population. Comparisons aforementioned will be made stratified into early- and new-generation devices. Differences of prosthetic geometry on CT between patients with BAV and TAV were presented. In addition, BAV morphological presentations in included studies were summarized. Method: Observational studies and a randomized controlled trial of patients with BAV undergoing TAVR were included according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Results: A total of 43 studies were included in the final analysis. In patients undergoing TAVR, type 1 BAV was the most common phenotype and type 2 BAV accounted for the least. Significant higher risks of conversion to surgical aortic valve replacement (SAVR), the need of a second valve, a moderate or severe paravalvular leakage (PVL), device failure, acute kidney injury (AKI), and stroke were observed in patients with BAV than in patients with TAV during hospitalization. BAV had a higher risk of new permanent pacemaker implantation (PPI) both at hospitalization and a 30-day follow-up. Risk of 1-year mortality was significantly lower in patients with BAV than that with TAV [odds ratio (OR) = 0.85, 95% CI 0.75-0.97, p = 0.01]. BE transcatheter heart valves (THVs) had higher risks of annular rupture but a lower risk of the need of a second valve and a new PPI than SE THVs. Moreover, BE THV was less expanded and more elliptical in BAV than in TAV. In general, the rates of clinical adverse events were lower in new-generation THVs than in early-generation THVs in both BAV and TAV. Conclusions: Despite higher risks of conversion to SAVR, the need of a second valve, moderate or severe PVL, device failure, AKI, stroke, and new PPI, TAVR seems to be a viable option for selected patients with severe bicuspid aortic stenosis (AS), which demonstrated a potential benefit of 1-year survival, especially among lower surgical risk population using new-generation devices. Larger randomized studies are needed to guide patient selection and verified the durable performance of THVs in the BAV population.

Evaluation of pyrrolidine-based analog of jaspine B as potential SphK1 inhibitors against rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovitise, and its pathogenesis is complicated. Sphingosine-1-phosphate (S1P) is a lipid produced by sphingosine kinase 1 and 2 (SphK1/2), which participate in some of most-spread skeletal diseases such as rheumatoid arthritis or osteoarthritis. To explore the anti-inflammatory activity of 2-epi-jaspine B analogs as SphKs inhibitors, we used LPS-induced rheumatoid arthritis fibroblast-like synovial cells (HFLS-RA) as the research object to evaluate the anti-inflammatory activity of 16 2-epi-jaspine B analogs and the newly synthesized salt CHJ01. We found that 2-epi-jaspine B analog CHJ01 in hydrochloride salt form has excellent SphK1 inhibitory effect and better anti-RA effect. CHJ01 showed an anti-inflammatory effect similar to that of MTX in vitro, its IC50 value is 8.64 µM. Moreover, the anti-RA effect of CHJ01 was also studied by using a Complete Freund's Adjuvant (CFA)-induced arthritis (AIA) in a rat mode. Pharmacological experiments show that CHJ01 can help to significantly improve the symptoms of rheumatoid arthritis by reducing the swelling volume, arthritis score, spleen index and the level of IL-1ß, TNF-α, IL-6 of AIA rats. Therefore, CHJ01 holds high potential for the treatment of RA.

Parametric upconversion of Ince-Gaussian modes.

The Ince-Gaussian (IG) mode, a recently discovered type of structured Gaussian beam, corresponds to eigenfunctions of the paraxial wave equation in elliptical coordinates. This propagation-invariant mode is of significance in various domains, in particular, its nonlinear transformation; however, there have been few relevant studies to date. In this Letter, we report the parametric upconversion of IG modes and associated full-field selection rule for the first time, to the best of our knowledge. We demonstrate that IG signals can be perfectly upconverted by a flattop-beam pump; in contrast, significant mode distortion occurred when using the most common Gaussian pump. Particular attention was given to the origin of the distortion, i.e., radial-mode degeneration induced by the sum-frequency generation excited by a Gaussian pump. This proof-of-principle demonstration has great significance in relevant areas, such as high-dimensional quantum frequency interfacing and upconversion imaging.

Diversity and metal tolerance of nematode-trapping fungi in Pb-polluted soils.

The diversity of nematode-trapping fungi (NTF) in two lead (Pb) mines in Yunnan Province, China was investigated in 2004. In total, 20 species belonging to five genera were identified from 500 samples collected at the Lanping and the Huize mines. Pb concentrations ranged from 216 approximately 7,150 mg/kg for the former and 132 approximately 13,380 mg/kg for the latter, respectively. The fungi were divided into five groups based on different trapping mechanisms. The trapping-net producer group contained the largest number of species, with nine. Two predators, Dactylellina ellipsosporum and Arthrobotrys oligospora, were found at frequencies of 32.85% and 15.41%, respectively. The diversity indexes of NTF were positively correlated with Pb pollution levels in both the Lanping Mine (r=0.66) and the Huize Mine (r=0.72), suggesting that the distribution of NTF was not negatively affected by Pb contamination. For most strains of a given species, there was no significant difference (P>0.01) in the Pb tolerance between the strains isolated from habitats with low or high Pb concentrations. However, Pb toxicity exerted adverse effects on trap formation and predacious capability of fungi. We discuss the possible metal tolerance mechanisms and their relationships to the survival strategy of NTF in Pb-polluted environments.