Chiral Inversion of Au40(SR)24 Nanocluster Driven by Rotation of Gold Tetrahedra in the Kekulé-like Core.

Studying the chiral characteristics and chiral inversion mechanisms of gold nanoclusters is important to promote their applications in the field of chiral catalysis and chiral recognition. Herein, we investigated the chiral inversion process of the Au40(SR)24 nanocluster and its derivatives using density functional theory calculations. The results showed that the chiral inversion process can be achieved by rotation of tetrahedra units in the gold core without breaking the Au-S bond. This work found that Au40 nanoclusters protected by different ligands have different chiral inversion mechanisms, and the difference is mainly attributable to the steric effects of the ligands. Moreover, the chiral inversion of the derivative clusters (Au34, Au28, and Au22) of the Au40 nanocluster can also be accomplished by the rotation of the Au4 tetrahedra units in the gold core. The energy barrier in the chiral inversion process of gold nanoclusters increases with the decrease of Au4 tetrahedra units in the gold core. This work identifies a chiral inversion mechanism with lower reaction energy barriers and provided a theoretical basis for the study of gold nanocluster chirality.

Type 2 diabetes mediates the causal relationship between obesity and osteomyelitis: A Mendelian randomization study.

Mendelian randomization (MR) analysis was used to determine the causal relationship between Type 2 diabetes (T2D) and osteomyelitis (OM). We performed MR analysis using pooled data from different large-scale genome-wide association studies (GWAS). Instrumental variables were selected based on genome-wide significance, instrumental strength was assessed using F-values, and thresholds for the number of exposed phenotypes were further adjusted by Bonferroni correction. univariable and multivariable MR analyses were performed to assess causal effects and proportions mediated by T2D. IVW (inverse variance weighting) showed a significant genetic effect of osteomyelitis on the following: After correction by Bonferroni, univariable analyses showed that childhood body mass index (BMI) was not significantly associated with genetic susceptibility to OM [odds ratio (OR), 1.26; 95% confidence interval (CI), 1.02, 1.55; P = .030], not significantly associated with adulthood BMI (OR, 1.28; 95% CI, 1.02, 1.61; P = .034), significantly associated with waist circumference (OR, 1.84; 95% CI, 1.51, 2.24; P < .001), and significantly associated with hip circumference (OR, 1.52; 95% CI, 1.31, 1.76; P < .001). Meanwhile, multivariable analyses showed no significant effect of childhood BMI on OM (OR, 1.16; 95% CI, 0.84, 1.62; P = .370), no significant effect of adulthood BMI on OM (OR, 0.42; 95% CI, 0.21, 0.84; P = .015), a significant association between waist circumference and OM (OR, 4.30; 95% CI, 1.89, 9.82; P = .001), T2D mediated 10% (95% CI, 0.02, 0.14), and no significant association between hip circumference and OM (OR, 1.01; 95% CI, 0.54, 1.90; P = .968). Our study provides evidence for a genetically predicted causal relationship among obesity, T2D, and OM. We demonstrate that increased waist circumference is positively associated with an increased risk of OM and that T2D mediates this relationship. Clinicians should be more cautious in the perioperative management of osteomyelitis surgery in obese patients with T2D. In addition, waist circumference may be a more important criterion to emphasize and strictly control than other measures of obesity.

The Classification of Lumbar Spondylolisthesis X-Ray Images Using Convolutional Neural Networks.

We aimed to develop and validate a deep convolutional neural network (DCNN) model capable of accurately identifying spondylolysis or spondylolisthesis on lateral or dynamic X-ray images. A total of 2449 lumbar lateral and dynamic X-ray images were collected from two tertiary hospitals. These images were categorized into lumbar spondylolysis (LS), degenerative lumbar spondylolisthesis (DLS), and normal lumbar in a proportional manner. Subsequently, the images were randomly divided into training, validation, and test sets to establish a classification recognition network. The model training and validation process utilized the EfficientNetV2-M network. The model's ability to generalize was assessed by conducting a rigorous evaluation on an entirely independent test set and comparing its performance with the diagnoses made by three orthopedists and three radiologists. The evaluation metrics employed to assess the model's performance included accuracy, sensitivity, specificity, and F1 score. Additionally, the weight distribution of the network was visualized using gradient-weighted class activation mapping (Grad-CAM). For the doctor group, accuracy ranged from 87.9 to 90.0% (mean, 89.0%), precision ranged from 87.2 to 90.5% (mean, 89.0%), sensitivity ranged from 87.1 to 91.0% (mean, 89.2%), specificity ranged from 93.7 to 94.7% (mean, 94.3%), and F1 score ranged from 88.2 to 89.9% (mean, 89.1%). The DCNN model had accuracy of 92.0%, precision of 91.9%, sensitivity of 92.2%, specificity of 95.7%, and F1 score of 92.0%. Grad-CAM exhibited concentrations of highlighted areas in the intervertebral foraminal region. We developed a DCNN model that intelligently distinguished spondylolysis or spondylolisthesis on lumbar lateral or lumbar dynamic radiographs.

Mechanism Insight into Metal Exchange between Au25(SR)18-/Ag25(SR)18- Clusters and Metal Ions from Ab Initio Molecular Dynamics Simulations.

The metal exchange reaction has emerged as an efficient method to synthesize ligand-protected alloy nanoclusters with precise compositions and structure. However, the understanding of the mechanism of these metal exchange processes is quite limited. Herein, the dynamic process of metal exchange of Au25(SR)18- and Ag25(SR)18- (R = CH3) nanoclusters with metal ions (Au+, Ag+, Cu2+, Cu+, Cd2+, and Hg2+) is investigated using ab initio molecular dynamics simulations. Computational results unveiled a multifaceted nature of the metal exchange process, dictated by several variables, including thermodynamic stability, electrochemical activity, metal affinity to ligand, and the coordination mode of metal ions. As a result of these factors, metal ions may either directly exchange with Au or Ag atoms on the icosahedral core surface by a "knock-off" mechanism or be stably adsorbed at the core-motif interface of Au25(SR)18- and Ag25(SR)18- nanoclusters. Meanwhile, we also discovered that counterions can promote adsorbed Ag and Cu atoms to diffuse into the gold core. Finally, the driving force of the galvanic reduction and antigalvanic reduction reactions is discussed. The formation of a more stable core-doping product nanocluster is the major driving force of metal exchange reactions.

[Pollution Characteristics, Source Apportionment, and Meteorological Response of Water-soluble Ions in PM2.5 in Xinxiang, North China].

Pollution variation, source characteristics, and meteorological effects of water-soluble inorganic ions (WSIIs) in PM2.5 were analyzed in Xinxiang city, Henan Province. PM2.5 samples and their chemical components were monitored online by using URG-9000 in four seasons:winter (January, 2022), spring (April, 2022), summer (July, 2022), and fall (October, 2022). The results showed that the TWSIIs had the same seasonal fluctuations as PM2.5. The average seasonal concentrations of WSIIs ranged from 19.62-72.15 µg·m-3, accounting for more than 60% of PM2.5, demonstrating that WSIIs were the major components of PM2.5. The annual concentration value of NO3-/SO42- was 2.11, which showed an increasing trend, suggesting predominantly mobile sources for secondary inorganic aerosols (SNA). Further, the molar concentration value [NH4+]/[NO3-] was 1.95, demonstrating that agriculture emissions were the dominant contributors to atmospheric nitrogen. Furthermore, the backward trajectory analysis showed that the concentrations of Ca2+ and Mg2+ were higher when the northeasterly wind prevailed and the wind speed was high. High values of SOR and NOR were correlated with low temperatures and high relative humidity (T < 8℃, RH > 60%), demonstrating that more gaseous precursors were converted into sulfate and nitrate. At high temperatures (T > 24℃), there was no apparent high NOR value like that for SOR, mainly due to the decomposition of NH4NO3 at high temperatures. Finally, backward trajectories associated with the PMF-resolved results were used to explore the regional transport characteristics. The results illustrated that dust sources in the study areas were mainly influenced by air trajectories originating from the northwest regions, whereas secondary sulfate, secondary nitrate, and biomass sources contributed more to WSIIs when wind speed and altitude air masses were low in the area surrounding the observation site.

Intramuscularly injected long-acting testosterone-cholesterol prodrug suspension with three different particle sizes: extended in vitro release and enhanced in vivo safety.

The testosterone undecanoate oil solution is the most widely used injection of testosterone for long-acting effects on the market, whereas the formulation carries the potential risk of causing pulmonary vascular embolism, inflammation, and pain at the injection site. Therefore, a sustained-released long-acting injection of testosterone with strong security is urgently exploited. Herein, a poorly water-soluble testosterone-cholesterol prodrug (TST-Chol) was synthesized by esterification. The water solubility of TST-Chol was decreased by 644 folds in comparison to that of testosterone (TST). Moreover, suspensions of TST and TST-Chol were prepared and analyzed in vitro, utilizing three distinct particle sizes: small-sized nanocrystals (SNCs) measuring 300 nm, medium-sized microcrystals (MMCs) measuring 12 µm, and large-sized microcrystals (LMCs) measuring 20 µm. The findings from the in vitro release study indicated that the sustained release of the drug was significantly influenced by the solubility and particle sizes of the suspension. Notably, the suspensions with low water solubility and larger particle sizes exhibited a more desirable sustained-release effect in vitro. Furthermore, the study on pharmacokinetics exhibited that TST-Chol SNCs produced a sustained TST plasma concentration in vivo for up to 40 days and no obvious pathological changes in lung tissue were found. Our study indicated that solubility and particle sizes of suspensions had made a difference in pharmacokinetics and provided a valuable reference for the advancement of long-acting injections.

The efficacy and safety of aspirin in preventing venous thrombosis in major orthopedic surgery: An updated meta-analysis of randomized controlled trials.

BACKGROUND: Major orthopedic surgery, including hip and knee replacement and lower extremity trauma fractures surgery, is associated with a high risk of venous thromboembolism (VTE), especially proximal deep vein thrombosis (DVT), and pulmonary embolism (PE), and is linked with high morbidity and mortality rates. Chemical anticoagulation is routinely used to prevent VTE, with previous meta-analyses reporting on the efficacy and safety of aspirin and other anticoagulants, however, opinions are divided. In the past 2 years, several large randomized controlled trials have been published, therefore, we reanalyzed aspirin efficacy and safety when compared with other anticoagulants in preventing VTE in major orthopedic surgery. METHODS: Using PubMed, The Cochrane Library, Embase, and Web of Science databases, we conducted a RCT search in August 2023. The main outcomes included VTE, proximal DVT or PE. Additional outcomes included bleeding events, wound complications, wound infections, blood transfusions, and death events. RESULTS: In total, 17 eligible articles, involving 29,522 patients (15,253 aspirin vs 14,269 other anticoagulant cases), were included. Primary outcomes showed that VTE incidence was more high in the aspirin group when compared with other anticoagulants (risk ratio [RR] = 1.45, 95% confidence interval [CI] = 1.18-1.77, P = .0004) and proximal in the aspirin group the DVT and/or PE incidence was significantly higher in the aspirin group when compared with other anticoagulants (RR = 1.19, 95% CI = 1.02-1.39, P = .03). No significant secondary outcome differences were identified in the aspirin group when compared with other anticoagulants (bleeding events [RR] = 0.83, 95% CI = 0.63-1.10, P = .20); wound complications (RR = 0.45, 95% CI = 0.20-1.04, P = .06); wound infection (RR = 1.08, 95% CI = 0.85-1.38, P = .53); blood transfusion events (RR = 1.00, 95% CI = 0.84-1.19, P = 1.00) and death events (RR = 1.11, 95% CI = 0.78-1.57, P = .55). CONCLUSIONS: Our updated meta-analysis showed that aspirin was inferior to when compared with other anticoagulants in VTE-related orthopedic major surgery, including proximal DVT and/or PE, and was more likely to form VTE. No differences between groups were identified for bleeding, wound complications, wound infections, transfusion, or death events.

Stem cell-based therapeutic strategies for rotator cuff tendinopathy.

Rotator cuff tendinopathy is a common musculoskeletal disorder that imposes significant health and economic burden. Stem cell therapy has brought hope for tendon healing in patients with final stage rotator cuff tendinopathy. Some clinical trials have confirmed the effectiveness of stem cell therapy for rotator cuff tendinopathy, but its application has not been promoted and approved. There are still many issues that should be solved prior to using stem cell therapy in clinical applications. The optimal source and dose of stem cells for rotator cuff tendinopathy should be determined. We also proposed novel prospective approaches that can overcome cell population heterogeneity and standardize patient types for stem cell applications. The translational potential of this article: This review explores the optimal sources of stem cells for rotator cuff tendinopathy and the principles for selecting stem cell dosages. Key strategies are provided for stem cell population standardization and recipient selection.

Ultrastable Cu-Based Dual-Channel Heterowire for the Switchable Electro-/Photocatalytic Reduction of CO2.

Catalytic conversion of CO2 into high value-added chemicals using renewable energy is an attractive strategy for the management of CO2 . However, achieving both efficiency and product selectivity remains a great challenge. Herein, a brand-new family of 1D dual-channel heterowires, Cu NWs@MOFs are constructed by coating metal-organic frameworks (MOFs) on Cu nanowires (Cu NWs) for electro-/photocatalytic CO2 reductions, where Cu NWs act as an electron channel to directionally transmit electrons, and the MOF cover acts as a molecule/photon channel to control the products and/or undertake photoelectric conversion. Through changing the type of MOF cover, the 1D heterowire is switched between electrocatalyst and photocatalyst for the reduction of CO2 with excellent selectivity, adjustable products, and the highest stability among the Cu-based CO2 RR catalysts, which leads to heterometallic MOF covered 1D composite, and especially the first 1D/1D-type Mott-Schottky heterojunction. Considering the diversity of MOF materials, the ultrastable heterowires offer a highly promising and feasible solution for CO2 reduction.

Hybrid Metal-Organic Frameworks Encapsulated Hybrid Ni-Doped CdS Nanoparticles for Visible-Light-Driven CO2 Reduction.

The photocatalytic production of syngas from CO2 and water is an attractive and straightforward way for both solar energy storage and sustainable development. Here, we combined the hybrid shell of a bimetallic metal-organic framework (MOF) Zn/Co-zeolitic imidazolate framework (ZIF) and the hybrid photoactive center of Ni-doped CdS nanoparticles (Ni@CdS) to construct a new "2 + 2" photocatalysis system Ni@CdS⊂Zn/Co-ZIF through a facile self-assembly process, which exhibited a double-synergic effect for visible light harvesting and CO2 conversion, leading to one of the highest photocatalytic syngas production rates and excellent recyclability. The H2/CO of syngas ratios can be readily adjusted by controlling the ratio of Zn/Co in the hybrid MOF shell.

Construction of metal-organic framework/polymer beads for efficient lead ions removal from water: Experiment studies and full-scale performance prediction.

Metal-organic frameworks (MOFs) show great promise in heavy metal removal; however, their applications are restricted by the poor separability and water instability. Herein, granular Zr-based MOF-polymer composite beads (MPCB(Zr)) (mean diameter âˆ¼ 1.74 mm) were synthesized using a facile dropping method, and applied on efficient lead ions (Pb(II)) removal. The as-prepared MPCB(Zr) demonstrated deep Pb(II) removal capability by reducing its concentration to âˆ¼ 0.002 mg L-1 after adsorption equilibrium at 360 min. The distribution coefficient for Pb(II) reached 8.0 × 106 mL g-1, and the theoretical adsorption capacity for Pb(II) was 144.5 mg g-1 (0.70 mmol g-1, 30 °C). The resulting MPCB(Zr) was highly selective for Pb(II), with the selectivity coefficient up to âˆ¼ 1.0-3.6 × 103 for the background cations (Na(I), K(I), Ca(II), and Mg(II)). Moreover, the MPCB(Zr) exhibited a broad working pH range (3.0-6.0) and satisfactory anti-interference to dissolved organic matters (humic acid and fuvic acid). Notably, the MPCB(Zr) also demonstrated excellent reusability with the Pb(II) removal efficiency over 99.0% after 20 cycles. Combined physicochemical characterizations unveiled that the thiol and oxygen-containing groups (e.g., hydroxyl, carboxylate) were responsible for the effective Pb(II) removal. To provide guidance for engineering application, the full-scale performance of the MPCB(Zr) under varying operation conditions was systematically evaluated via the validated pore surface diffusion model. This work provides an effective methodology to construct macroscopic MOF-polymer beads for effective Pb(II) removal, and promote the actual application of MOFs in water treatment.

Comparison of Tendon Development Versus Tendon Healing and Regeneration.

Tendon is a vital connective tissue in human skeletal muscle system, and tendon injury is very common and intractable in clinic. Tendon development and repair are two closely related but still not fully understood processes. Tendon development involves multiple germ layer, as well as the regulation of diversity transcription factors (Scx et al.), proteins (Tnmd et al.) and signaling pathways (TGFß et al.). The nature process of tendon repair is roughly divided in three stages, which are dominated by various cells and cell factors. This review will describe the whole process of tendon development and compare it with the process of tendon repair, focusing on the understanding and recent advances in the regulation of tendon development and repair. The study and comparison of tendon development and repair process can thus provide references and guidelines for treatment of tendon injuries.

Atomistic Molecular Dynamics Simulation Study on the Interaction between Atomically Precise Thiolate-Protected Gold Nanoclusters and Phospholipid Membranes.

The interaction of atomically precise monolayer thiolate (SR) protected gold nanoclusters (Au NCs) with the phospholipid membranes has been studied by the all-atom molecular dynamics (AAMD) simulations. The effect of cluster size, type, and the surface charge density of protection ligand was studied. The simulation results show gold nanoclusters with different size and surface modifications have much different transmembrane behaviors. The Au25(SR)18 cluster was found to possess the best affinity to the phospholipid membranes among six atomically accurate clusters Au25(SR)18, Au36(SR)24, Au44(SR)28, Au68(SR)32, Au144(SR)60, and Au314(SR)96. Using the Au25 NC as a model, this work also found that the aggregation mode of the surface ligands and the surface charge density are the important factors affecting the interaction between the gold nanoclusters and the phospholipid membranes. Moreover, the balance of hydrophilic and hydrophobic ligands on the surface of Au NCs is beneficial to the high permeability.

[Seasonal Variation, Source Identification, and Health Risk of PM2.5-bound Metals in Xinxiang].

This study analyzed the seasonal variation, sources, and source-specific health risks of PM2.5-bound metals in Xinxiang city, Henan province. A total of 112 daily PM2.5 samples were collected over four consecutive seasons during 2019-2020. In total, 19 elements were identified using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The annual concentrations of PM2.5 and 11 heavy metals were calculated to be (66.25±35.73) µg·m-3 and (1.32±0.84) µg·m-3, respectively. Strong seasonal variations were observed in PM2.5 concentrations and the concentrations of associated metal elements, with the lowest concentrations all occurring in summer. The highest concentrations of dust-related elements (e.g., Al, Ca, Fe, Mg,and Ti) were recorded in spring, differing significantly from other elements, which all exhibited the highest mass concentrations in winter. The results apportioned from positive matrix factorization (PMF) and potential source contribution function (PSCF) models showed that the major sources of PM2.5-bound elements were Ni-and Co-related emissions (5.8%), motor vehicles (13.7%), Cd-related emissions(5.1%), combustion emissions (18.2%), and dust (57.3%). Health risk models showed that there were no obvious non-carcinogenic risks associated with these metals, because their hazard quotient (HQ) values were all below 1. Lifetime carcinogenic risks of the five apportioned sources were all higher than the acceptable level (1×10-6). Of these five sources, combustion emissions were the largest contributors to cancer risk (8.74×10-6, 36.9%) and non-cancer risk (0.60, 25.6%). This study suggests that control strategies to mitigate exposure risk in Xinxiang should emphasize reducing the sources of combustion emissions.

Construction of CuII Defects on CuCl Nanoparticles in Metal-Organic Frameworks toward Composite Catalysts with Superior Activity.

Metal-organic frameworks (MOFs) represent an ideal platform for the construction of highly active composite catalysts. However, loading metastable and/or multicomponent metal compounds into MOFs remains a synthetic bottleneck due to the great challenge of keeping the guest and matrix intact during the preparation of a composite. In this work, we develop a new impregnation reduction surface modification (IRSM) strategy to give a new composite catalyst CuCl@MIL-101(Cr), which is successfully postmodified by in situ construction of CuII defects on the surface of loaded CuCl inside MOF pores, leading to the new composite material CuII/CuI@MIL-101(Cr). The new dual-component composite catalyst exhibits a hierarchical structure and superior catalytic activity in C-C homocoupling of arylboronic acids under green conditions. This study presents a facile strategy for improving the catalytic activity by constructing defects on the surface of MOF-based catalysts as well as for forming multiple-component composite materials.

Exploration of Formation and Size-Evolution Pathways of Thiolate-Gold Nanoclusters in the CO-Directed [Au25 (SR)18 ]- Synthesis.

An intermolecular association and decarboxylation mechanism is proposed to understand the experimental evidence of the stepwise 2e- hopping in the reductant-assisted thiolate-gold cluster synthesis. Based on the newly proposed intermolecular reaction mechanism, a total of 19 molecular-like reaction equations are deduced to account for the bottom-up formation of 2e- -8e- gold nanoclusters in the CO-directed [Au25 (SR)18 ]- synthesis. With these established reaction equations, atomic pathways of three prototype cluster-size evolution reactions are comprehensively explored in the course of [Au25 (SR)18 ]- synthesis, namely, the conversion of 0e- homoleptic Au(I) -SR complexes to the 2e- intermediate Au15 (SR)13 cluster, the size-evolution of 2e- Au15 (SR)13 cluster to the 4e- -8e- cluster (stepwise 2e- -hopping), and the isoelectronic addition reaction of [Au23 (SR)16 ]- to the [Au25 (SR)18 ]- . The studies reveal that the CO can combine with the Au(I)-complex to form [Aux (SR)x -COOH]- species in the alkaline condition, which acts as the active precursors in the 2e- hopping cluster-size evolution process. Lastly, as a conceptual extension of the mechanistic studies of the CO-reduction system, a similar intermolecular reaction mechanism is proposed for the 2e- reduction in the conventional "NaBH4 reduction" system.

Functional Analysis of StPHT1;7, a Solanum tuberosum L. Phosphate Transporter Gene, in Growth and Drought Tolerance.

PHT1 (phosphate transporter 1) family genes play important roles in regulating plant growth and responding to stress. However, there has been little research on the role of the PHT1 family in potatoes. In this study, using molecular and bioinformatic approaches, 8 PHT1 family genes were identified from the potato genome. StPHT1;7 was highly expressed in the whole potato plants. The overexpression and silence vectors of StPHT1;7 were constructed and transformed into the potato cultivar Desiree. Consequently, StPHT1;7 overexpression (with a relative expression 2-7-fold that in the control) and silence lines (with a relative expression of 0.3%-1% that in the control) were obtained. Their growth vigor was ranked in the order overexpression line > wild type > silence line. In the absence of phosphorus, the root length of the overexpression line was approximately 2.6 times that of the wild type, while the root length of the silence line was approximately 0.6 times that of the wild type. Furthermore, their tolerance to drought stress was ranked as wild type > overexpression line > silence line. These results suggest that StPHT1;7 affects growth and stress tolerance in potato plants.

Genome-Wide Analysis of the Lateral Organ Boundaries Domain (LBD) Gene Family in Solanum tuberosum.

Lateral organ boundaries domain (LBD) proteins belong to a particular class of transcription factors of lateral organ boundary (LOB) specific domains that play essential roles in plant growth and development. However, a potato phylogenetic analysis of the LBD family has not been fully studied by scholars and researchers. In this research, bioinformatics methods and the growth of potatoes were used to identify 43 StLBD proteins. We separated them into seven subfamilies: Ia, Ib, Ic, Id, Ie, IIa and IIb. The number of amino acids encoded by the potato LBD family ranged from 94 to 327. The theoretical isoelectric point distribution ranged from 4.16 to 9.12 Kda, and they were distributed among 10 chromosomes. The results of qRT-PCR showed that the expression levels of StLBD2-6 and StLBD3-5 were up-regulated under drought stress in the stem. The expression levels of StLBD1-5 and StLBD2-6 were down-regulated in leaves. We hypothesized that StLBD1-5 was down-regulated under drought stress, and that StLBD2-6 and StLBD3-5 up-regulation might help to maintain the normal metabolism of potato and enhance the potatoes' resistance to drought.