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1.
ACS Nano ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39165001

RESUMO

Topological spin textures are of great significance in magnetic information storage and spintronics due to their high storage density and low drive current. In this work, the transformation of magnetic configuration from chaotic labyrinth domains to uniform stripe domains was observed in MnFe1-xCoxGe magnets. This change occurs due to the noncollinear magnetic structure switching to a uniaxial ferromagnetic structure with increasing Co content, as identified by neutron diffraction results and Lorentz transmission electron microscopy (L-TEM). Of utmost importance, a hexagonal lattice of high-density robust type-II magnetic bubble lattice was established for x = 0.8 through out-of-plane magnetic field stimulation and field-cooling. The dimensions of the type-II magnetic bubbles were found to be tuned by the sample thickness. Therefore, the stabilization of complex magnetic spin textures, associated with enhanced uniaxial ferromagnetic interaction and magnetic dipole-dipole interaction in MnFe1-xCoxGe through magnetic structure manipulation, as further confirmed by the micromagnetic simulations, will provide a convenient and efficient strategy for designing topological spin textures with potential applications in spintronic devices.

2.
Front Bioeng Biotechnol ; 12: 1442606, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39165405

RESUMO

Introduction: Lower limb exoskeletons have shown considerable potential in assisting human walking, particularly by reducing metabolic cost (MC), leading to a surge of interest in this field in recent years. However, owing to significant individual differences and the uncertainty of movements, challenges still exist in the personalized design and control of exoskeletons in human-robot interactions. Methods: In this study, we propose a hybrid data-driven approach that integrates musculoskeletal simulation with machine learning technology to customize personalized assistance strategies efficiently and adaptively for ankle-foot exoskeletons. First, optimal assistance strategies that can theoretically minimize MC, were derived from forward muscle-driven simulations on an open-source dataset. Then, a neural network was utilized to explore the relationships among different individuals, movements, and optimal strategies, thus developing a predictive model. Results: With respect to transfer learning, our approach exhibited effectiveness and adaptability when faced with new individuals and movements. The simulation results further indicated that our approach successfully reduced the MC of calf muscles by approximately 20% compared to normal walking conditions. Discussion: This hybrid approach offers an alternative for personalizing assistance strategy that may further guide exoskeleton design.

3.
J Vet Pharmacol Ther ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39149982

RESUMO

The objective of this study was to determine the pharmacokinetics of enrofloxacin and its metabolite, ciprofloxacin, in Nanyang cattle after a single intravenous (IV), and intramuscular (IM) administration of enrofloxacin at 2.5 mg/kg body weight (BW). Blood samples were collected at predetermined time points. Enrofloxacin and ciprofloxacin concentrations in plasma were simultaneously determined using a high-performance liquid chromatography (HPLC) assay method and subjected to a non-compartmental analysis. After IV administration, enrofloxacin had a mean (±SD) volume of distribution at steady state (VSS) of 1.394 ± 0.349 L/kg, a terminal half-life (t1/2λz) of 3.592 ± 1.205 h, and a total body clearance (Cl) of 0.675 ± 0.16 L/h/kg. After IM administration, enrofloxacin was absorbed relatively slowly but completely, with a mean absorption time (MAT) of 6.051 ± 1.107 h and a bioavailability of 99.225 ± 7.389%. Both compounds were detected simultaneously in most plasma samples following both routes of administration, indicating efficient biotransformation of enrofloxacin to ciprofloxacin. After IV injection, the peak concentration (Cmax) of ciprofloxacin was 0.315 ± 0.017 µg/mL, observed at 0.958 ± 0.102 h. Following IM injection, the corresponding values were 0.071 ± 0.006 µg/mL and 3 ± 1.095 h, respectively. Following IV and IM administration, the conversion ratio of enrofloxacin to ciprofloxacin was calculated as 59.2 ± 9.6% and 31.2 ± 7.7%, respectively. The present results demonstrated favorable pharmacokinetic profiles for enrofloxacin, characterized by complete absorption with relatively slow kinetics, extensive distribution, efficient biotransformation to ciprofloxacin, and prolonged elimination in Nanyang cattle.

4.
Sci Total Environ ; 948: 174649, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39025138

RESUMO

BACKGROUND: Significant efforts have been devoted to assess the effects of the poly-gamma-glutamic acid (γ-PGA) on crop growth, yield and quality, soil water retention and fertilizer use efficiency. However, few studies have evaluated the effects of γ-PGA on greenhouse gas (GHG) emissions and grain yield from paddy fields with different rice varieties. METHODS: In the present study, a split-plot field experiment was performed to comprehensively evaluate the effects of γ-PGA concentrations (i.e., no application [P0] and 25.0 kg ha-1 of γ-PGA fermentation solution [P1]) and rice varieties (i.e., conventional rice [Huanghuazhan, H], red rice [Gangteyou 8024, R] and black rice [Black indica rice, B]) on the grain yield, GHG emissions, global warming potential (GWP), greenhouse gas intensity (GHGI), net ecosystem economic profit (NEEP) and carbon footprint (CF) during 2022 and 2023 rice-growing seasons in central China. RESULTS: Application of γ-PGA significantly affected the GHGs emissions, NEEP and CF. Compared with P0 treatments, P1 treatments significantly increased the NEEP by 1.2-11.2 %, and decreased the GWP by 12.9-35.4 %, the GHGI by 16.5-35.9 % and the CF by 13.8-26.2 % in 2022-2023. Application of γ-PGA showed a tendency to increase the yield. Under γ-PGA application condition, R treatment exhibited the lowest GWP, GHGI and CF, and the highest yield and NEEP compared with B and H treatments. CONCLUSION: Our results suggest that γ-PGA application is an ecological agricultural management to increase rice yield, reduce greenhouse gas emission and increase economic benefit, and its advantage is more significant for red rice than for other rice varieties.


Assuntos
Gases de Efeito Estufa , Oryza , Oryza/crescimento & desenvolvimento , Gases de Efeito Estufa/análise , China , Ácido Poliglutâmico/análogos & derivados , Agricultura/métodos , Fertilizantes , Grão Comestível/crescimento & desenvolvimento , Aquecimento Global
5.
PLoS Pathog ; 20(7): e1012321, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38990823

RESUMO

Vibriosis is one of the most serious diseases that commonly occurs in aquatic animals, thus, shaping a steady inherited resistance trait in organisms has received the highest priority in aquaculture. Whereas, the mechanisms underlying the development of such a resistance trait are mostly elusive. In this study, we constructed vibriosis-resistant and susceptible families of the Pacific white shrimp Litopenaeus vannamei after four generations of artificial selection. Microbiome sequencing indicated that shrimp can successfully develop a colonization resistance trait against Vibrio infections. This trait was characterized by a microbial community structure with specific enrichment of a single probiotic species (namely Shewanella algae), and notably, its formation was inheritable and might be memorized by host epigenetic remodeling. Regardless of the infection status, a group of genes was specifically activated in the resistant family through disruption of complete methylation. Specifically, hypo-methylation and hyper-expression of genes related to lactate dehydrogenase (LDH) and iron homeostasis might provide rich sources of specific carbon (lactate) and ions for the colonization of S. algae, which directly results in the reduction of Vibrio load in shrimp. Lactate feeding increased the survival of shrimp, while knockdown of LDH gene decreased the survival when shrimp was infected by Vibrio pathogens. In addition, treatment of shrimp with the methyltransferase inhibitor 5-azacytidine resulted in upregulations of LDH and some protein processing genes, significant enrichment of S. algae, and simultaneous reduction of Vibrio in shrimp. Our results suggest that the colonization resistance can be memorized as epigenetic information by the host, which has played a pivotal role in vibriosis resistance. The findings of this study will aid in disease control and the selection of superior lines of shrimp with high disease resistance.


Assuntos
Resistência à Doença , Microbioma Gastrointestinal , Penaeidae , Vibrioses , Vibrio , Animais , Penaeidae/microbiologia , Penaeidae/imunologia , Vibrioses/imunologia , Resistência à Doença/genética , Aquicultura
6.
Front Cell Dev Biol ; 12: 1431558, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39011392

RESUMO

Care for patients with peripheral nerve injury is multifaceted, as traditional methods are not devoid of limitations. Although the utilization of neural conduits shows promise as a therapeutic modality for peripheral nerve injury, its efficacy as a standalone intervention is limited. Hence, there is a pressing need to investigate a composite multifunctional neural conduit as an alternative treatment for peripheral nerve injury. In this study, a BDNF-loaded chitosan-based mimetic mussel polymer conduit was prepared. Its unique adhesion characteristics allow it to be suture-free, improve the microenvironment of the injury site, and have good antibacterial properties. Researchers utilized a rat sciatic nerve injury model to evaluate the progression of nerve regeneration at the 12-week postoperative stage. The findings of this study indicate that the chitosan-based mimetic mussel polymer conduit loaded with BDNF had a substantial positive effect on myelination and axon outgrowth. The observed impact demonstrated a favorable outcome in terms of sciatic nerve regeneration and subsequent functional restoration in rats with a 15-mm gap. Hence, this approach is promising for nerve tissue regeneration during peripheral nerve injury.

7.
Food Chem ; 455: 139961, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850983

RESUMO

Apple flesh tends to turn mealy and textural deterioration commonly occurs during storage. The comparative investigation of three sub-fractions separated from sodium carbonate-soluble pectin (SSP) of 'Hongjiangjun' apples between crisp and mealy stages was performed to unveil the textural alterations related to mealiness. In situ immunofluorescence labelling showed that galactans declined in parenchyma cell walls during the fruit mealiness. FTIR analysis, monosaccharide compositions and structural polymers configurated that loss of rhammogalacturonan-I (RG-I) from SSP sub-fragments (SC0.0-P and S-M0.0-P) might be closely involved in the mealiness. The NMR spectroscopy revealed that loss of the substituted galactans from α-Rhap residues repeat unit in SC0.0-P constituting RG-I in crisp stage that subsequently converted to S-M0.0-P in mealy stage might be closely associated with the modifications of pectin in cell walls during mealiness. These findings provided novel evidence for understanding the underlying modifications of SSP polymers during the mealiness of 'Hongjiangjun' apples.


Assuntos
Parede Celular , Frutas , Malus , Pectinas , Malus/química , Pectinas/química , Frutas/química , Parede Celular/química , Carbonatos/química , Polissacarídeos/química
8.
J Phys Chem A ; 128(22): 4467-4473, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38783510

RESUMO

Understanding kinetic isotope effects is important in the study of the reaction dynamics of elementary chemical reactions, particularly those involving hydrogen atoms and molecules. As one of the isotopic variants of the hydrogen exchange reaction, the D + para-H2 reaction has attracted much attention. However, experimental studies of this reaction have been limited primarily due to its strong experimental background noise. In this study, by using the velocity map ion imaging method and the near-threshold ionization technique, together with improvements on the vacuum condition in the vicinity of the collision zone, background noise was reduced significantly, and quantum state-resolved differential cross sections (DCSs) for the D + para-H2 reaction at a collision energy of 1.21 eV were acquired in a crossed molecular beams experiment. Interestingly, clear rotational state-dependent angular distributions were noticed in the quantum state-resolved DCSs. The most intense peak's positions for HD (v', j') products shift to different scattering directions as the product's ro-vibrational quantum number increases. Two different microscopic reaction mechanisms are found to be involved in this reaction for HD products in different vibrational states. The results show a direct correlation between the scattering angle and the product's rotational quantum number, revealing that the contributions of impact parameters are strongly influenced by the corresponding centrifugal barrier.

9.
ACS Appl Mater Interfaces ; 16(21): 27917-27925, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38744687

RESUMO

Three-dimensional (3D) vector magnetic sensors play a significant role in a variety of industries, especially in the automotive industry, which enables the control of precise position, angle, and rotation of motion elements. Traditional 3D magnetic sensors integrate multiple sensors with their sensing orientations along the three coordinate axes, leading to a large size and inevitable nonorthogonal misalignment. Here, we demonstrate a wide linearity range 3D magnetic sensor utilizing a single L10-FePt Hall-bar device, whose sensitivity is 291 VA-1 T-1 in the z-axis and 27 VA-1 T-1 in the in-plane axis. Based on the spin-orbit torque-dominated magnetization reversal, the linear response of anomalous Hall resistance within a large linear range (±200 Oe) for the x, y, and z components of magnetic fields has been obtained, respectively. Typically, it exhibits a relatively lower magnetic noise level of 7.9 nV at 1 Hz than previous results, improving measurement resolution at the low frequency. Furthermore, we provide a straightforward approach for noncontact angular position detection based on a single Hall-bar device, which shows great potential for application in rotational motion control.

10.
J Orthop Surg (Hong Kong) ; 32(2): 10225536241256245, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38763777

RESUMO

BACKGROUND: While previous research has demonstrated potential advantages of unicompartmental knee arthroplasty (UKA) over total knee arthroplasty (TKA), particularly in terms of clinical outcomes such as function and pain relief, the specific impact on health-related quality of life (HRQOL) remains unclear. This systematic review and meta-analysis aim to address this gap by comparing HRQOL outcomes between UKA and TKA, providing valuable insights for clinical decision-making. METHODS: We conducted a literature search in the PubMed, Embase, Cochrane Controlled Register of Trials (CENTRAL), and Web of Science databases up to July 15, 2023. Eligible studies assessed HRQOL using EQ-5D, SF-36, or SF-12 and were assessed for methodological quality using the Newcastle-Ottawa Scale (NOS). RESULTS: Seven eligible studies were included, comprising a total of 64,585 patients with 35,809 undergoing TKA and 28,776 undergoing UKA. Patient age ranged from 52.0 to 67.7 years with an average BMI ranging from 27.2 to 31.0 kg/m2. Follow-up periods ranged from 6 months to 10 years. Five studies (63,829 patients) that evaluated HRQOL using EQ-5D showed significantly better outcomes for UKA compared to TKA (MD -0.04, 95% CI -0.05 to -0.02). Two studies (756 patients) that evaluated HRQOL using SF-36 showed no significant difference between TKA and UKA. Five studies (63,286 patients) that evaluated functional outcomes using Oxford Knee Score (OKS) showed significantly better functional scores for UKA compared to TKA (MD -1.29, 95% CI -1.86 to -0.72). Four studies (24,570 patients) that reported patient satisfaction showed no statistically significant difference between TKA and UKA (MD 0.97, 95% CI 0.90 to 1.05). Further subgroup analysis did not affect the conclusions. CONCLUSIONS: Our meta-analysis suggests that UKA is associated with better HRQOL and knee function, as well as similar patient satisfaction, compared to TKA for patients with unicompartmental osteoarthritis.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Qualidade de Vida , Humanos , Artroplastia do Joelho/métodos , Osteoartrite do Joelho/cirurgia
11.
Biology (Basel) ; 13(5)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38785782

RESUMO

Vibrio parahaemolyticus is one of the main causative agents leading to acute hepatopancreatic necrosis disease, the severe bacterial disease that occurs during shrimp aquaculture. Hemocytes play important roles during Vibrio infection. Previously, we found that there were few differentially expressed genes (DEGs) between hemocytes from V. parahaemolyticus-resistant and -susceptible shrimp before infection. We considered that there should be different immune responses between them after a pathogen infection. Here, the transcriptome data of hemocytes from V. parahaemolyticus-resistant and -susceptible shrimp before and after a pathogen infection were compared. The results showed that there were 157 DEGs responsive to infection in V. parahaemolyticus-resistant shrimp, while 33 DEGs in V. parahaemolyticus-susceptible shrimp. DEGs in V. parahaemolyticus-resistant shrimp were mainly related to immune and glycolytic processes, while those in V. parahaemolyticus-susceptible shrimp were mainly related to metabolism, with only two DEGs in common. A further analysis of genes involved in glucose metabolism revealed that GLUT2, HK, FBP, and PCK1 were lowly expressed while PC were highly expressed in hemocytes of the V. parahaemolyticus-resistant shrimp, indicating that glucose metabolism in shrimp hemocytes was related to a V. parahaemolyticus infection. After the knockdown of PC, the expression of genes in Toll and IMD signaling pathways were down-regulated, indicating that glucose metabolism might function through regulating host immunity during V. parahaemolyticus infection. The results suggest that the immune responses between V. parahaemolyticus-resistant and -susceptible shrimp were apparently different, which probably contribute to their different V. parahaemolyticus resistance abilities.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38614872

RESUMO

OBJECTIVES: Age and sex characteristics are evident in cephalometric radiographs (CRs), yet their accurate estimation remains challenging due to the complexity of these images. This study aimed to harness deep learning to automate age and sex estimation from CRs, potentially simplifying their interpretation. STUDY DESIGN: We compared the performance of 4 deep learning models (SVM, R-net, VGG16-SingleTask, and our proposed VGG16-MultiTask) in estimating age and sex from the testing dataset, utilizing a VGG16-based multitask deep learning model on 4,557 CRs. Gradient-weighted class activation mapping (Grad-CAM) was incorporated to identify sex. Performance was assessed using mean absolute error (MAE), specificity, sensitivity, F1 score, and the area under the curve (AUC) in receiver operating characteristic analysis. RESULTS: The VGG16-MultiTask model outperformed the others, with the lowest MAE (0.864±1.602) and highest sensitivity (0.85), specificity (0.88), F1 score (0.863), and AUC (0.93), demonstrating superior efficacy and robust performance. CONCLUSIONS: The VGG multitask model demonstrates significant potential in enhancing age and sex estimation from cephalometric analysis, underscoring the role of AI in improving biomedical interpretations.


Assuntos
Cefalometria , Redes Neurais de Computação , Determinação do Sexo pelo Esqueleto , Humanos , Masculino , Feminino , Determinação do Sexo pelo Esqueleto/métodos , Adolescente , Sensibilidade e Especificidade , Determinação da Idade pelo Esqueleto/métodos , Criança , Adulto , Aprendizado Profundo
13.
Heliyon ; 10(7): e28411, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38590884

RESUMO

Multiple myeloma (MM) is a plasma cell malignancy that remains incurable and poses a significant threat to global public health. The multifunctional transcription factor c-Myc plays a crucial role in various cellular processes and is closely associated with MM progression. As part of the basic-helix-loop-helix-leucine zipper (bHLHZip) family, c-Myc forms heterodimers with its obligate partner Max, binds to the Enhancer-box (E-box) of DNA, and ultimately co-regulates gene expression. Therefore, impeding the capacity for heterodimerization to bind to DNA represents a favored strategy in thwarting c-Myc transcription. In this study, we first synthesized a series of novel 2-iminobenzimidazole derivatives and further estimated their potential anti-MM activity. Notably, among all the derivatives, 5b and 5d demonstrated remarkable inhibitory activity against RPMI-8226 and U266 cells, with IC50 values of 0.85 µM and 0.97 µM for compound 5b, and 0.96 µM and 0.89 µM for compound 5d. Western blot and dual-luciferase reporter assays demonstrated that compounds 5b and 5d effectively suppressed both c-Myc protein expression and transcriptional activity of the c-Myc promoter in RPMI-8226 and U266 cells. Furthermore, these compounds induced apoptosis and G1 cell cycle arrest in the aforementioned MM cells. Molecular docking studies revealed that 5b and 5d exhibited strong binding affinity to the interface between c-Myc/Max and E-box of DNA. Taken together, our findings suggest that further investigations are warranted for potential therapeutic applications of 5b and 5d for c-Myc-related diseases.

14.
Front Pediatr ; 12: 1363419, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500589

RESUMO

Tracheal stenosis is a rare but life-threatening disease in preterm infants. Misdiagnosis as congenital tracheal stenosis is common, making surgical management challenging. This report presents a case of a preterm infant with tracheal stenosis and congenital heart malformation treated with ECMO-assisted tracheal resection and end-to-end anastomosis. A male infant was born at 30 weeks of gestation with severe asphyxia, cardiac insufficiency, and pneumonia. Following failed medical treatment, fiberoptic bronchoscopy confirmed mid-tracheal to carinal stenosis. After a 2-week treatment course, ECMO-assisted tracheal resection and end-to-end anastomosis were performed successfully. This case confirms the feasibility of tracheal resection and end-to-end anastomosis in low-weight, preterm infants with tracheal stenosis born at 30 weeks gestation. The utilization of ECMO for oxygenation during surgery provides a clear surgical field and shorter operating time. Surgical intervention may be necessary for neonatal tracheal stenosis depending on the clinical presentation.

15.
J Colloid Interface Sci ; 663: 601-608, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38428117

RESUMO

Li-rich layered oxides cathodes (LLOs) as the promising next-generation cathode materials can provide ultrahigh capacity and energy density due to their distinctive anionic redox chemistry. Unfortunately, severe interfacial side reactions, surface structural degradation and sluggish Li+ kinetics have resulted in low initial coulombic efficiency (ICE), capacity decay and poor rate performance, restricting their practical applications for high-energy-density lithium-ion batteries. Herein, Surface structure regulation strategy used as surface modified agent is proposed to activate the anionic redox chemistry via ammonium tungstate treatment. Experimental results showcase that dual coating layer spinel-like structure LiMn2O4 and Li2WO4 have been successfully constructed on the surface of LLOs. The surface spinel-like structure providing 3 D Li+ diffusion channels together with fast-ion conductive layer decrease the interfacial Li+ diffusion barrier and boost the fasting Li+ kinetics. In addition, the in-situ reconstruction layer can further alleviate the interfacial side reactions and reinforce the surface structural stability. As a result, the ICE of modified LLOs can be precisely increased from 74.71 % to 107.42 % with the adjustment of ammonium tungstate usage. Moreover, it delivers a high reversible capacity of 279.5 mAh/g at 0.1 C, as well as excellent rate capability with capacity of 147.2 mAh/g at 5 C. This work provides a significant reference for designing high-energy-density LLOs via surface structure regulation strategy.

16.
Small ; 20(33): e2401132, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38552226

RESUMO

Li-rich layered oxides cathodes (LLOs) have prevailed as the promising high-energy-density cathode materials due to their distinctive anionic redox chemistry. However, uncontrollable anionic redox process usually leads to structural deterioration and electrochemical degradation. Herein, a Mo/Cl co-doping strategy is proposed to regulate the relative position of energy band for modulating the anionic redox chemistry and strengthening the structural stability of Co-free Li1.16Mn0.56Ni0.28O2 cathodes. The incorporation of Mo with high d state orbit and Cl with low electronegativity can narrow the band energy gap between bonding and antibonding bands via increasing the filled lower-Hubbard band (LHB) and decreasing the non-bonding O 2p energy bands, promoting the anionic redox reversibility. In addition, strong covalent Mo─O and Mn─Cl bonding further increases the covalency of Mn─O band to further stabilize the O2 n- species and enhance the reversible distortion of MnO6 octahedron. The strengthening electronic conductivity, together with the epitaxial structure Li2MoO4 facilitates the fast Li+ kinetics. As a result, the dual doping material exhibits enhanced anionic redox reversibility and suppressed oxygen release with increased cyclic stability and excellent rate performance. This strategy provides some guidance to design high-energy-density LLOs with desirable anionic redox reversibility and stable crystal structure via band structure engineering.

17.
Org Lett ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38385808

RESUMO

An intermolecular Suzuki-Miyaura-type reaction of benzoyl fluorides with alkyl boronic acids to synthetic ketone was revealed by cooperative N-heterocyclic carbene (NHC) and photoredox catalysis. Various alkyl boric acids can be converted into alkyl radicals without external oxidants or activators. Moreover, the catalytic system was feasible for the difunctionalization of styrenes via a radical relay process. Mechanistic experiments suggested that the benzoate anion intermediate might play a unique role in this reaction system.

18.
Dev Comp Immunol ; 154: 105146, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38316231

RESUMO

Microbial drug resistance is becoming increasingly severe due to antibiotic abuse. The development and utilization of antimicrobial peptides is one of the important ways to solve this difficult problem. Crustins are a family of antimicrobial peptides that play important roles in the innate immune system of crustaceans. Several types of crustins exist in shrimp and their activities vary greatly. In the present study, we studied the immune function of one newly identified crustin and found that the type VI crustin encoding gene in Litopenaeus vannamei (LvCrustinVI) was mainly expressed in gills. Its expression was significantly up-regulated after Vibrio parahaemolyticus infection and knockdown of the gene promoted Vibrio proliferation in the hepatopancreas of shrimp, indicating that LvCrustinVI was involved in pathogens infection. The recombinant LvCrustinVI (rLvCrustinVI) showed strong inhibitory activities against both Gram-negative and Gram-positive bacteria, and exhibited binding activities with the bacteria and bacterial polysaccharides including Glu, LPS and PGN. In the presence of Ca2+, rLvCrustinVI showed a strong agglutination effect on V. parahaemolyticus and could significantly enhance the phagocytic ability of shrimp hemocytes against V. parahaemolyticus. In conclusion, LvCrustinVI played important roles as antimicrobial peptide and opsonin in the innate immune defense of L. vannamei. The study enriched our understanding of the functional activity of Crustin and provides an important basis for the development and utilization of antimicrobial peptides.


Assuntos
Penaeidae , Vibrioses , Vibrio parahaemolyticus , Animais , Peptídeos Antimicrobianos , Imunidade Inata/genética , Antibacterianos/metabolismo , Proteínas de Artrópodes , Filogenia
19.
Nat Commun ; 15(1): 1698, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402199

RESUMO

Quantum interference between reaction pathways around a conical intersection (CI) is an ultrasensitive probe of detailed chemical reaction dynamics. Yet, for the hydrogen exchange reaction, the difference between contributions of the two reaction pathways increases substantially as the energy decreases, making the experimental observation of interference features at low energy exceedingly challenging. We report in this paper a combined experimental and theoretical study on the H + HD → H2 + D reaction at the collision energy of 1.72 eV. Although the roaming insertion pathway constitutes only a small fraction (0.088%) of the overall contribution, angular oscillatory patterns arising from the interference of reaction pathways were clearly observed in the backward scattering direction, providing direct evidence of the geometric phase effect at an energy of 0.81 eV below the CI. Furthermore, theoretical analysis reveals that the backward interference patterns are mainly contributed by two distinct groups of partial waves (J ~ 10 and J ~ 19). The well-separated partial waves and the geometric phase collectively influence the quantum reaction dynamics.

20.
J Cancer Res Clin Oncol ; 150(1): 5, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170235

RESUMO

PURPOSE: The application of platinum-based chemotherapeutic agents is the traditional treatment paradigm for advanced and metastatic urothelial carcinoma, which has changed with the advent of immune checkpoint inhibitors (ICIs). This study aims to evaluate the efficacy of ICI therapy versus chemotherapy in the treatment of advanced and metastatic urothelial carcinoma. METHODS: A systematic literature search of Web of Science, Embase, PubMed, and Cochrane Central Register of Controlled Trials was performed by two independent investigators. The primary endpoint was overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and adverse events (AEs). RESULTS: The patients treated with ICI monotherapy had no significant difference in OS than those treated with chemotherapy monotherapy (HR: 0.965, 95% CI 0.865-1.076, p = 0.518). However, the patients treated with ICI monotherapy had a higher ORR and lower incidence of high-grade (≥ grade 3) AEs than those treated with chemotherapy monotherapy (OR: 0.568, 95% CI 0.479-0.675, p < 0.001; OR: 0.614, 95% CI 0.446-0.845, p = 0.003). The patients treated with ICI in combination with chemotherapy had significantly better OS and PFS than those treated with chemotherapy alone (HR: 0.862, 95% CI 0.776-0.957, p = 0.006; HR: 0.788, 95% CI 0.707-0.879, p < 0.001). However, there was no significant difference in ORR or the incidence of grade 3 or higher AEs (OR: 0.951, 95% CI 0.582-1.554, p = 0.841; OR: 0.942, 95% CI 0.836-1.062, p = 0.328). CONCLUSION: ICI monotherapy did not show statistically significant difference in OS but demonstrated higher ORR and lower incidence of high-grade (≥ grade 3) AEs. And a statistically significant OS and PFS benefit was found in patients treated with first-line ICI in combination with chemotherapy compared to chemotherapy alone.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Platina , Intervalo Livre de Progressão
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