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1.
Heliyon ; 10(14): e34250, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39130482

RESUMEN

Background: Osteoporosis is a debilitating condition characterized by reduced bone density and microstructure, leading to increased susceptibility to fractures and increased mortality, particularly among older individuals. Despite the availability of drugs for osteoporosis treatment, the need for targeted and innovative agents with fewer adverse effects persists. Trifolirhizin, a natural pterostalin derived from the root of Sophora flavescens, has been previously studied for its effects on certain anticancer and antiinflammatory. The impact of trifolirhizin on the formation and function of osteoclasts remain unclear. Purpose: Herein, the possible roles of trifolirhizin the formation and function of osteoclasts and the underlying mechanism were explored. Methods: Bone marrow-derived macrophages (BMMs) were employed to evaluate the roles of trifolirhizin on steoclastogenesis, bone absorption and the underlying mechanism in vitro. Bone loss model was established by ovariectomy(OVX) in mice in vivo. Results: Trifolirhizin repressed osteoclastogenesis, bone resorption induced by receptor activator of nuclear factor kappa B ligand (RANKL) in vitro. Mechanistically, trifolirhizin inhibits RANKL-induced MAPK signal transduction and NFATc1 expression. Moreover, trifolirhizin inhibited osteoclast marker gene expression, including NFATc1, CTSK, MMP9, DC-STAMP, ACP5, and V-ATPase-D2. Additionally, trifolirhizin was found to protect against ovariectomy(OVX)-induced bone loss in mice. Conclusion: Trifolirhizin can effectively inhibit osteoclast production and bone resorption activity. The results of our study provide evidence for trifolirhizin as a potential drug for the prevention and treatment of osteoporosis and other osteolytic diseases.

2.
ACS Nano ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115190

RESUMEN

Organic-inorganic hybrid metal halide perovskite solar cells have been considered as one of the most promising next-generation photovoltaic technologies. Nevertheless, perovskite defects and Li+ ionic migration will seriously affect the power conversion efficiency and stability of the formal device. Herein, we designed two crown ether derivatives (PC12 and PC15) with different cavity diameters, which selectively bind to different metal cations. It is found that PC15 in perovskite precursor solution can actively regulate the nucleation and crystallization processes and passivate the uncoordinated Pb2+ ions, while PC12 at the interface between the perovskite layer and hole-transporting layer can effectively inhibit the migration of Li+ ions and reduce nonradiative recombination losses. Therefore, PC12 and PC15 can act as "lubricant" and defect passivators, as well as inhibitors of ion migration, when they are synergistically applied at the surface and bulk of perovskite layer. Consequently, the optimized device achieved a champion efficiency of 24.8% with significantly improved humidity, thermal, and light stability.

3.
Anal Chem ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967251

RESUMEN

As one of the most common cancers, accurate, rapid, and simple histopathological diagnosis is very important for breast cancer. Raman imaging is a powerful technique for label-free analysis of tissue composition and histopathology, but it suffers from slow speed when applied to large-area tissue sections. In this study, we propose a dual-modal Raman imaging method that combines Raman mapping data with microscopy bright-field images to achieve virtual staining of breast cancer tissue sections. We validate our method on various breast tissue sections with different morphologies and biomarker expressions and compare it with the golden standard of histopathological methods. The results demonstrate that our method can effectively distinguish various types and components of tissues, and provide staining images comparable to stained tissue sections. Moreover, our method can improve imaging speed by up to 65 times compared to general spontaneous Raman imaging methods. It is simple, fast, and suitable for clinical applications.

4.
Macromol Rapid Commun ; : e2400433, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023423

RESUMEN

The fabrication of the flexible devices with excellent photovoltaic performance and stability is critical for the commercialization of organic solar cells (OSCs). Herein, the conjugated dimer acceptor DY-TVCl and the non-conjugated dimer acceptor DY-3T based on the monomer MY-BO are synthesized to regulate the molecular glass transition temperatures (Tg) for improving the morphology stability of active layer films. And the crack onset strain values for the blend films based on dimer acceptors are superior than that of small molecule, which are beneficial for the preparation of flexible devices. Accordingly, the binary device based on PM6:DY-TVCl achieves a maximum power conversion efficiency (PCE) of 18.01%. Meanwhile, the extrapolated T80 (time to reach 80% of initial PCE) lifetimes of the PM6:DY-TVCl-based device and PM6:DY-3T-based device are 3091 and 2227 h under 1-sun illumination, respectively, which are better than that of the PM6:MY-BO-based device (809 h). Furthermore, the flexible devices based on DY-TVCl and DY-3T exhibit the efficiencies of 15.23% and 14.34%, respectively. This work affords a valid approach to improve the stability and mechanical robustness of OSCs, as well as ensuring the reproducibility of organic semiconductors during mass production.

5.
Histopathology ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-39031601

RESUMEN

BACKGROUND AND AIMS: Nuclear protein testis (NUT) carcinoma (NC) is a rare and highly aggressive tumour characterised by chromosomal rearrangement of the nuclear protein testis family member 1 (NUTM1) gene, also known as the NUT gene. NC occurs mainly in the head and neck, mediastinum and lung. In general, primary NC in the oral cavity is extremely rare and reported sporadically. METHODS: A total of 111 formalin-fixed and paraffin-embedded specimens of poorly differentiated oral and oropharyngeal tumours were collected from 10 hospitals. NUT protein IHC staining was performed on these samples, and fluorescence in-situ hybridisation (FISH) and RNA sequencing detection were further carried out for NUT IHC-positive cases. RESULTS: The expression of NUT protein in tumour cells was detected in five cases (five of 111, 4.5%). The tumours in these cases were located in the oral floor, lip, base of the tongue, gingiva and hard palate. FISH detection results showed BRD4::NUT rearrangement in three patients and a non-BRD4::NUT rearrangement pattern in two patients. RNA sequencing results confirmed BRD4::NUT rearrangement in two cases. CONCLUSIONS: To our knowledge, this is the first and largest retrospective study of oral NC, and we found that NC is easily misdiagnosed as poorly differentiated oral squamous cell carcinoma (SCC) or poorly differentiated carcinoma. The morphology and immunophenotype of four NC cases were similar to SCC, and abrupt keratinisation was observed in three cases. Therefore, it is necessary to detect NUT protein for NC screening in oral malignant tumours with these morphologies, especially for young patients who are more likely to be misdiagnosed with other types of cancer.

6.
Nat Commun ; 15(1): 6255, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39048547

RESUMEN

Evolution of SARS-CoV-2 variants emphasizes the need for multivalent vaccines capable of simultaneously targeting multiple strains. SCTV01E is a tetravalent COVID-19 vaccine derived from the spike protein of SARS-CoV-2 variants Alpha, Beta, Delta, and Omicron BA.1. In this double-blinded placebo-controlled pivotal efficacy trial (NCT05308576), the primary endpoint was vaccine efficacy (VE) against COVID-19 seven days post-vaccination in individuals without recent infection. Other endpoints included evaluating safety, immunogenicity, and the VE against all SARS-CoV-2 infections in individuals meeting the study criteria. Between December 26, 2022, and January 15, 2023, 9,223 individuals were randomized at a 1:1 ratio to receive SCTV01E or a placebo. SCTV01E showed a VE of 69.4% (95% CI: 50.6, 81.0) 7 days post-vaccination, with 75 cases in the placebo group and 23 in the SCTV01E group for the primary endpoint. VEs were 79.7% (95% CI: 51.0, 91.6) and 82.4% (95% CI: 57.9, 92.6), respectively, for preventing symptomatic infection and all SARS-CoV-2 infections 14 days post-vaccination. SCTV01E elicited a 25.0-fold higher neutralizing antibody response against Omicron BA.5 28 days post-vaccination compared to placebo. Reactogenicity was generally mild and transient, with no reported vaccine-related SAE, adverse events of special interest (AESI), or deaths. The trial aligned with the shift from dominant variants BA.5 and BF.7 to XBB, suggesting SCTV01E as a potential vaccine alternative effective against present and future variants.


Asunto(s)
Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Eficacia de las Vacunas , Humanos , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/efectos adversos , Método Doble Ciego , Femenino , Masculino , COVID-19/prevención & control , COVID-19/inmunología , COVID-19/virología , SARS-CoV-2/inmunología , Adulto , Persona de Mediana Edad , Anticuerpos Antivirales/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Neutralizantes/inmunología , Anciano , Adulto Joven , Inmunogenicidad Vacunal , Adolescente , Vacunación/métodos
7.
PLoS One ; 19(7): e0307866, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39052687

RESUMEN

A cup of tea can be made in one of the two ways: the milk or the tea infusion was first added to the cup. The Lady Tasting Tea experiment consists in mixing eight cups of tea, four in one way and four in the other, and presenting them to the Lady for judgment in a random order. This short article presents a Bayesian Network (BN) for modelling the Lady Tasting Tea experiment that provides a comprehensive perspective in inferential analysis of all the data samples possibly generated from the experiment. More specifically, with respect to a prior distribution of three possible levels (pure guessing, 75% sure, and 100% sure) of the Lady's ability in correctly deciding how a served cup of tea has been made, the proposed BN model enables us to calculate the posterior probabilities of any judgment outcomes possibly made by the Lady.


Asunto(s)
Teorema de Bayes , , Té/química , Humanos , Gusto , Femenino
8.
ACS Appl Mater Interfaces ; 16(32): 42332-42342, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39084210

RESUMEN

Lithium metal anode has attracted wide attention due to its ultrahigh theoretical specific capacity, lowest reduction potential, and low density. However, uncontrollable dendritic growth and volume change caused by uneven Li+ deposition still seriously hinder the large-scale commercial application of lithium metal batteries, even causing serious battery explosions and other safety problems. Hence, gold nanoparticles with a gradient distribution anchored on 3D carbon fiber paper (CP) current collectors followed by the encapsulation of polydopamine (PDA) (CP/Au/PDA) are constructed for stable and dendrite-free Li metal anodes for the first time. Significantly, lithiophilic Au nanoparticles showing a gradient distribution in the carbon fiber paper could guide the transfer of Li+ from the outside to the inside of the CP/Au/PDA electrode as well as lower the nucleation overpotential of Li, thereby obtaining the uniform Li deposition. Meanwhile, the PDA layer could in situ be converted to Li-PDA which could serve as an efficient Li+ conductor to further facilitate uniform Li+ transport among the whole CP/Au/PDA electrode. Besides, 3D carbon fiber paper could effectively accommodate the volume change during the plating/stripping process of Li metal. As a result, CP/Au/PDA electrodes deliver a low nucleation overpotential (∼9 mV) and a high Coulombic efficiency (mean value of ∼98.8%) at a current density of 1 mA cm-2 with the capacity of 1 mA h cm-2. Furthermore, Li@CP/Au/PDA electrodes also can demonstrate an ultralow voltage hysteresis (∼20 mV) and a long cycle life (1000 h) in symmetric cells. Finally, with LiFePO4 (LFP) as the cathode, the Li@CP/Au/PDA-LFP full cell delivers a high discharge capacity of 136 mA h g-1 even after 350 cycles at 1C, exhibiting a per cycle loss as low as 0.01%. This gradient lithium ion regulation current collector is of great significance for the development of lithium metal anodes.

9.
J Interprof Care ; : 1-9, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899500

RESUMEN

Undertaking an authentic interprofessional simulation experience may be a useful and consistent strategy for healthcare professional students to build competencies required for a rural healthcare context. An observational comparative study design was adopted to evaluate a clinical simulation experience created to develop the interprofessional competencies of a sample of healthcare professional students at a regional university situated on multiple campuses in New South Wales (NSW), Australia. Over 200 students across three campuses of the university were involved in a simulation experience that included four interprofessional activities. Of these students, 189 (89%) agreed to participate in the study. The healthcare professional students who participated in the study were from second year occupational therapy, physiotherapy, and podiatry, and third year speech pathology programs. Retrospective pre and post self-assessed interprofessional collaborative competencies were compared for all students using the revised Interprofessional Collaborative Attainment Survey (ICCAS). Results demonstrated a statistically significant improvement in self-perceived scores using the validated revised ICCAS survey. The findings of this study suggest that carefully designed and authentic interprofessional simulation experiences can facilitate the development of competencies required for effective interprofessional practice, which are necessary for successful rural practice.

10.
Gene ; 923: 148551, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-38759737

RESUMEN

Odorant-binding proteins (OBPs) are crucial in insect olfaction. The most abundant expressed OBP of citrus psyllids, DcitOBP9 encodes 148 amino acids. DcitOBP9 lacks a transmembrane structure and possesses a 17-amino acid signal peptide at the N-terminus. Characterized by the six conserved cysteine sites, DcitOBP9 is classified as the Classical-OBP family. RT-qPCR experiments revealed ubiquitous expression of DcitOBP9 across all developmental stages of the citrus psyllid, with predominant expression in adults antennae. Fluorescence competitive binding assays demonstrated DcitOBP9's strong affinity for ocimene, linalool, dodecanoic acid, and citral, and moderate affinity for dimethyl trisulfide. Additionally, it binds to myrcia, (-)-trans-caryophyllene, (±)-Citronellal, nonanal, and (+)-α-pinene. Among them, ocimene, linalool, and dodecanoic acid were dynamically bound to DcitOBP9, while citral was statically bound to DcitOBP9. Molecular docking simulations with the top five ligands indicated that amino acid residues V92, S72, P128, L91, L75, and A76 are pivotal in the interaction between DcitOBP9 and these odorants. These findings suggest DcitOBP9's involvement in the citrus psyllid's host plant recognition and selection behaviors, thereby laying a foundation for elucidating the potential physiological and biological functions of DcitOBP9 and developing attractants.


Asunto(s)
Hemípteros , Proteínas de Insectos , Simulación del Acoplamiento Molecular , Receptores Odorantes , Animales , Hemípteros/genética , Hemípteros/metabolismo , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/química , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Receptores Odorantes/química , Citrus/metabolismo , Citrus/genética , Unión Proteica , Secuencia de Aminoácidos , Filogenia
11.
Small ; : e2401485, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38712455

RESUMEN

Dual channel photo-driven H2O2 production in pure water on small-scale on-site setups is a promising strategy to provide low-concentrated H2O2 whenever needed. This process suffers, however, strongly from the fast recombination of photo-generated charge carriers and the sluggish oxidation process. Here, insoluble Keggin-type cesium phosphomolybdate Cs3PMo12O40 (abbreviated to Cs3PMo12) is introduced to carbonized cellulose (CC) to construct S-scheme heterojunction Cs3PMo12/CC. Dual channel H2O2 photosynthesis from both H2O oxidation and O2 reduction in pure water has been thus achieved with the production rate of 20.1 mmol L-1 gcat. -1 h-1, apparent quantum yield (AQY) of 2.1% and solar-to-chemical conversion (SCC) efficiency of 0.050%. H2O2 accumulative concentration reaches 4.9 mmol L-1. This high photocatalytic activity is guaranteed by unique features of Cs3PMo12/CC, namely, S-scheme heterojunction, electron reservoir, and proton reservoir. The former two enhance the separation of photo-generated charge carriers, while the latter speeds up the torpid oxidation process. In situ experiments reveal that H2O2 is formed via successive single-electron transfer in both channels. In real practice, exposing the reaction system under natural sunlight outdoors successfully results in 0.24 mmol L-1 H2O2. This work provides a key practical strategy for designing photocatalysts in modulating redox half-reactions in photosynthesis.

12.
Insights Imaging ; 15(1): 115, 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38735018

RESUMEN

OBJECTIVES: The simplified endoscopic score of Crohn's disease (SES-CD) is the gold standard for quantitatively evaluating Crohn's disease (CD) activity but is invasive. This study aimed to develop and validate a machine learning (ML) model based on dual-energy CT enterography (DECTE) to noninvasively evaluate CD activity. METHODS: We evaluated the activity in 202 bowel segments of 46 CD patients according to the SES-CD score and divided the segments randomly into training set and testing set at a ratio of 7:3. Least absolute shrinkage and selection operator (LASSO) was used for feature selection, and three models based on significant parameters were established based on logistic regression. Model performance was evaluated using receiver operating characteristic (ROC), calibration, and clinical decision curves. RESULTS: There were 110 active and 92 inactive bowel segments. In univariate analysis, the slope of spectral curve in the venous phases (λHU-V) has the best diagnostic performance, with an area under the ROC curve (AUC) of 0.81 and an optimal threshold of 1.975. In the testing set, the AUC of the three models established by the 7 variables to differentiate CD activity was 0.81-0.87 (DeLong test p value was 0.071-0.766, p > 0.05), and the combined model had the highest AUC of 0.87 (95% confidence interval (CI): 0.779-0.959). CONCLUSIONS: The ML model based the DECTE can feasibly evaluate CD activity, and DECTE parameters provide a quantitative analysis basis for evaluating specific bowel activities in CD patients. CRITICAL RELEVANCE STATEMENT: The machine learning model based on dual-energy computed tomography enterography can be used for evaluating Crohn's disease activity noninvasively and quantitatively. KEY POINTS: Dual-energy CT parameters are related to Crohn's disease activity. Three machine learning models effectively evaluated Crohn's disease activity. Combined models based on conventional and dual-energy CT have the best performance.

13.
Small ; : e2400712, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38770994

RESUMEN

As one of the main components of solid propellant, ammonium perchlorate (AP) shows slow sluggish decomposition kinetics with unconcentrated heat release. To achieve efficient catalytical decomposition, it is a significant challenge to design reasonable catalyst structure and explore the interaction between catalyst and AP. Herein, a series of porous carbon supported spinel-typed homogeneous heterometallic composites CuxCo3-xO4/C via pyrolysis of MOF-74-Co doped Cu. On basis of precise electronic-structure-tuning through modulating Cu/Co ratio in MOF-74, Cu0.15Co2.85O4/C with 5% Cu-doping featuring oxygen vacancy concentration of 26.25% exhibits the decrease to 261.5 °C with heat release up to 1222.1 J g-1 (456.9 °C and 669.2 J g-1 for pure AP). The detail process of AP accelerated decomposition is approved by TG-DSC-FTIR-MS technique. Density functional theory calculation revealed that in the Cu0.15Co2.85O4/C, the distinctive ability for NH3 catalyzed oxidation assisted with absorption performance of active porous C boosts accelerating AP decomposition. The findings would provide an insight for perceiving and understanding AP catalytic decomposition.

14.
Nanomaterials (Basel) ; 14(6)2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38535695

RESUMEN

Nowadays, two of the biggest obstacles restricting the further development of methanol fuel cells are excessive cost and insufficient catalytic activity of platinum-based catalysts. Herein, platinum nanoparticle supported graphene aerogel (Pt/3DGA) was successfully synthesized by a one-step hydrothermal self-assembly method. The loose three-dimensional structure of the aerogel is stabilized by a simple one-step method, which not only reduces cost compared to the freeze-drying technology, but also optimizes the loading method of nanoparticles. The prepared Pt/3DGA catalyst has a three-dimensional porous structure with a highly cross-linked, large specific surface area, even dispersion of Pt NPs and good electrical conductivity. It is worth noting that its catalytic activity is 438.4 mA/mg with long-term stability, which is consistent with the projected benefits of anodic catalytic systems in methanol fuel cells.. Our study provides an applicable method for synthesizing nano metal particles/graphene-based composites.

15.
Angew Chem Int Ed Engl ; 63(22): e202403695, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38436549

RESUMEN

Aqueous zinc ion batteries (AZIBs) show a great potential for next-generation energy storage due to their high safety and high energy density. However, the severe side reactions of zinc negative electrode largely hinder the further application of AZIBs. Herein, trace tris(hydroxymethyl)aminomethane (Tris) additive with rich lone-pair-electrons and zincophilic sites is firstly introduced to achieve long-term and highly reversible Zn plating/stripping. Specifically, Tris not only regulates the solvation structure of Zn2+, but is also adsorbed vertically on the Zn anode surface with a changed coordination intensity during the plating/stripping process of Zn to generate an in situ dynamic adsorption layer for the first time. The dynamic adsorption layer could successively attract the solvated Zn2+ and then promote the de-solvation of the solvated Zn2+ owing to the orientation polarization with regularly-changed applied electric field, the volume rejection effect, and strong intermolecular force towards H2O of the vertically-adsorbed Tris. Therefore, an improved Zn2+-transport kinetics as well as the inhibition of side reactions of Zn anode are successfully realized. Accordingly, the Zn||Zn symmetric cell provides an ultra-long cycle life of 2600 h. Furthermore, the Zn||MnO2 full cell with Tris could demonstrate a high capacity and structural stability for practical applications.

16.
Angew Chem Int Ed Engl ; 63(20): e202403083, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38502273

RESUMEN

Dopant-free hole transport materials (HTMs) are ideal materials for highly efficient and stable n-i-p perovskite solar cells (PSCs), but most current design strategies for tailoring the molecular structures of HTMs are limited to single strategy. Herein, four HTMs based on dithienothiophenepyrrole (DTTP) core are devised through dual-strategy methods combining conjugate engineering and side chain engineering. DTTP-ThSO with ester alkyl chain that can form six-membered ring by the S⋅⋅⋅O noncovalent conformation lock with thiophene in the backbone shows good planarity, high-quality film, matching energy level and high hole mobility, as well as strong defect passivation ability. Consequently, a remarkable power conversion efficiency (PCE) of 23.3 % with a nice long-term stability is achieved by dopant-free DTTP-ThSO-based PSCs, representing one of the highest values for un-doped organic HTMs based PSCs. Especially, the fill factor (FF) of 82.3 % is the highest value for dopant-free small molecular HTMs-based n-i-p PSCs to date. Moreover, DTTP-ThSO-based devices have achieved an excellent PCE of 20.9 % in large-area (1.01 cm2) devices. This work clearly elucidates the structure-performance relationships of HTMs and offers a practical dual-strategy approach to designing dopant-free HTMs for high-performance PSCs.

17.
Materials (Basel) ; 17(5)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38473551

RESUMEN

This study elucidates the thermodynamic reaction mechanism of the GeCl4 hydrogen reduction process for Ge preparation. Five independent reactions in the Ge-Cl-H ternary system were identified, utilizing the phase law, mass conservation principles, and thermodynamic data, with H2 as the reducing agent. Additionally, the effects of the temperature, feed ratio, and pressure on the germanium deposition rate during the GeCl4 hydrogen reduction process were investigated, guided by these five reactions. The results indicate that, with fixed temperature and pressure, a higher feed ratio (nH2/nGeCl4) leads to an increased germanium deposition rate. Conversely, with a constant feed ratio, increased pressure results in a lower deposition rate at low temperatures. The optimal operating conditions for germanium preparation via the hydrogen reduction of GeCl4 were determined: the temperature was 450 °C, the feed ratio was 20, the pressure was 0.1 MPa, and the deposition rate of the germanium was 36.12% under this condition.

18.
Rice (N Y) ; 17(1): 12, 2024 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-38310612

RESUMEN

BACKGROUND: Hybrid rice has significant yield advantage and stress tolerance compared with inbred rice. However, production of hybrid rice seeds requires extensive manual labors. Currently, hybrid rice seeds are produced by crosspollination of male sterile lines by fertile paternal lines. Because seeds from paternal lines can contaminate the hybrid seeds, mechanized production by mixed-seeding and mixed-harvesting is difficult. This problem can be solved if the paternal line is female sterile. RESULTS: Here we identified a female infertile mutant named h569 carrying a novel mutation (A1106G) in the MEL2 gene that was previously reported to regulate meiosis entry both in male and female organs. h569 mutant is female infertile but male normal, suggesting that MEL2 regulates meiosis entry in male and female organs through distinct pathways. The MEL2 gene and h569 mutant gave us tools to construct female sterility maintaining systems that can be used for propagation of female sterile lines. We connected the wild-type MEL2 gene with pollen-killer gene ZmAA1 and seed-marker gene DsRed2 in one T-DNA cassette and transformed it into ZZH1607, a widely used restorer line. Transgenic line carrying a single transgene inserted in an intergenic region was selected to cross with h569 mutant. F2 progeny carrying homozygous A1106G mutation and hemizygous transgene displayed 1:1 segregation of fertile and infertile pollen grains and 1:1 segregation of fluorescent and non-fluorescent seeds upon self-fertilization. All of the non-fluorescent seeds generated female infertile plants, while the fluorescent seeds generated fertile plants that reproduced in the way as their previous generation. CONCLUSIONS: These results indicated that the female sterility maintaining system constructed in the study can be used to breed and propagate paternal lines that are female infertile. The application of this system will enable mechanized production of hybrid rice seed by using the mixed-seeding and mixed harvesting approach, which will significantly reduce the cost in hybrid rice seed production.

19.
Vet Surg ; 53(3): 447-459, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38380523

RESUMEN

OBJECTIVE: To determine the influence of screw configuration on the reduction and stabilization of simulated complete lateral condylar fracture. STUDY DESIGN: Randomized experimental crossover study. METHODS: A lateral condylar fracture was simulated in 18 cadaver limbs from nine horses. Each limb underwent repair with 4.5 mm diameter cortex screws, tightened to 4 Nm, in a linear and triangular configuration. Computed tomography (CT) of each repair was performed with the limbs in unloaded and loaded conditions. Fracture gaps were measured at the dorsal, palmar, and middle locations of the third metacarpal condyle. Fracture gap measurements were graded 0-4, based on voxels. Following descriptive analysis, a Bayesian network (BN) model was fitted to the data. RESULTS: The median fracture grade was 0 (range: 0-4) for unloaded linear repairs and 2 (0-4) for loaded linear repairs. The median fracture grade was 0 (0-3) for unloaded triangular repairs and 1 (0-3) for loaded triangular repairs. Bayesian network sensitivity analysis showed that the construct configuration reduced the uncertainty in the measured fracture outcome by 0.8%. CONCLUSION: Triangular screw configuration resulted in better fracture reduction and stability in comparison with linear screw configuration. However, the BN sensitivity analysis results showed that the effect of construct configuration on fracture outcome was weak. CLINICAL SIGNIFICANCE: These findings indicate a low probability that triangular repair of lateral condylar fracture will result in improved outcomes, when compared with linear repair.


Asunto(s)
Fracturas Óseas , Enfermedades de los Caballos , Huesos Metatarsianos , Caballos , Animales , Teorema de Bayes , Estudios Cruzados , Fracturas Óseas/veterinaria , Tornillos Óseos/veterinaria , Extremidad Superior , Fenómenos Biomecánicos , Huesos Metatarsianos/cirugía , Fijación Interna de Fracturas/veterinaria
20.
Angew Chem Int Ed Engl ; 63(10): e202318646, 2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38231189

RESUMEN

Generally, two-dimensional gold nanomaterials have unique properties and functions that offer exciting application prospects. However, the crystal phases of these materials tend to be limited to the thermodynamically stable crystal structure. Herein, we report a DNA framework-templated approach for the ambient aqueous synthesis of freestanding and microscale amorphous gold nanosheets with ultrathin sub-nanometer thickness. We observe that extended single-stranded DNA on DNA nanosheets can induce site-specific metallization and enable precise modification of the metalized nanostructures at predefined positions. More importantly, the as-prepared gold nanosheets can serve as an electrocatalyst for glucose oxidase-catalyzed aerobic oxidation, exhibiting enhanced electrocatalytic activity (~3-fold) relative to discrete gold nanoclusters owing to a larger electrochemical active area and wider band gap. The proposed DNA framework-templated metallization strategy is expected to be applicable in a broad range of fields, from catalysis to new energy materials.


Asunto(s)
Oro , Nanoestructuras , Oro/química , Nanoestructuras/química , Oxidación-Reducción , ADN , Agua
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