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1.
Vet Res ; 55(1): 67, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783392

RESUMEN

Porcine reproductive and respiratory syndrome (PRRS), caused by the PRRS virus (PRRSV), has caused substantial economic losses to the global swine industry due to the lack of effective commercial vaccines and drugs. There is an urgent need to develop alternative strategies for PRRS prevention and control, such as antiviral drugs. In this study, we identified ursonic acid (UNA), a natural pentacyclic triterpenoid from medicinal herbs, as a novel drug with anti-PRRSV activity in vitro. Mechanistically, a time-of-addition assay revealed that UNA inhibited PRRSV replication when it was added before, at the same time as, and after PRRSV infection was induced. Compound target prediction and molecular docking analysis suggested that UNA interacts with the active pocket of PTPN1, which was further confirmed by a target protein interference assay and phosphatase activity assay. Furthermore, UNA inhibited PRRSV replication by targeting PTPN1, which inhibited IFN-ß production. In addition, UNA displayed antiviral activity against porcine epidemic diarrhoea virus (PEDV) and Seneca virus A (SVA) replication in vitro. These findings will be helpful for developing novel prophylactic and therapeutic agents against PRRS and other swine virus infections.


Asunto(s)
Antivirales , Inmunidad Innata , Virus del Síndrome Respiratorio y Reproductivo Porcino , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Triterpenos , Replicación Viral , Animales , Virus del Síndrome Respiratorio y Reproductivo Porcino/fisiología , Virus del Síndrome Respiratorio y Reproductivo Porcino/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Inmunidad Innata/efectos de los fármacos , Antivirales/farmacología , Porcinos , Triterpenos/farmacología , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Plantas Medicinales/química , Síndrome Respiratorio y de la Reproducción Porcina/inmunología , Síndrome Respiratorio y de la Reproducción Porcina/virología
2.
J Hosp Infect ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38705475

RESUMEN

INTRODUCTION: The prevention and control of hospital-acquired infections remain a significant challenge worldwide, as textiles used in hospital wards are highly involved in transmission processes. Herein, we report a new antibacterial medical fabric used to prepare hospital pillowcases, bottom sheets, and quilt covers for controlling and reducing hospital-acquired infections. METHOD: The medical fabric was composed of blended yarns of staple polyester and degradable poly(3-hydroxybutyrate co-3-hydroxyvalerate)/polylactide fibres, which were then coated with polylactide oligomers, an environmentally friendly and safe antimicrobial agent with excellent thermal stability in high-temperature laundry. A clinical trial was conducted with emphasis on the bacterial species that were closely related to the infection cases in the trial hospital. RESULT: After 7 days of usage, 94% of PET/PHBV/PLA-PLAO fabric could keep less than 20 CFU/100 cm2 of total bacterial amount, meeting hygiene and cleanliness standards. CONCLUSION: This study demonstrates the potential of fabrics containing polyhydroxyalkanoate oligomers as highly effective, safe, and long-lasting antimicrobial medical textiles that can effectively reduce the incidence of hospital-acquired infections.

3.
Theor Appl Genet ; 137(5): 110, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656338

RESUMEN

KEY MESSAGE: We developed T1AL·1PS and T1AS·1PL Robertsonian translocations by breakage-fusion mechanism based on wheat-A. cristatum 1P(1A) substitution line with smaller leaf area, shorter plant height, and other excellent agronomic traits Agropyron cristatum, a wild relative of wheat, is a valuable germplasm resource for improving wheat genetic diversity and yield. Our previous study confirmed that the A. cristatum chromosome 1P carries alien genes that reduce plant height and leaf size in wheat. Here, we developed T1AL·1PS and T1AS·1PL Robertsonian translocations (RobTs) by breakage-fusion mechanism based on wheat-A. cristatum 1P (1A) substitution line II-3-1c. Combining molecular markers and cytological analysis, we identified 16 spontaneous RobTs from 911 F2 individuals derived from the cross of Jimai22 and II-3-1c. Fluorescence in situ hybridization (FISH) was applied to detect the fusion structures of the centromeres in wheat and A. cristatum chromosomes. Resequencing results indicated that the chromosomal junction point was located at the physical position of Triticum aestivum chromosome 1A (212.5 Mb) and A. cristatum chromosome 1P (230 Mb). Genomic in situ hybridization (GISH) in pollen mother cells showed that the produced translocation lines could form stable ring bivalent. Introducing chromosome 1PS translocation fragment into wheat significantly increased the number of fertile tillers, grain number per spike, and grain weight and reduced the flag leaf area. However, introducing chromosome 1PL translocation fragment into wheat significantly reduced flag leaf area and plant height with a negative effect on yield components. The pre-breeding of two spontaneous RobTs T1AL·1PS and T1AS·1PL was important for wheat architecture improvement.


Asunto(s)
Agropyron , Cromosomas de las Plantas , Fitomejoramiento , Translocación Genética , Triticum , Triticum/genética , Triticum/crecimiento & desarrollo , Triticum/anatomía & histología , Agropyron/genética , Agropyron/crecimiento & desarrollo , Cromosomas de las Plantas/genética , Hibridación Fluorescente in Situ , Fenotipo
4.
J Ethnopharmacol ; 331: 118263, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38677575

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellaria baicalensis Georgi (Scutellariae Radix, SR) and Coptis chinensis Franch (Coptidis Rhizoma, CR) is a classic herbal pair used in many Traditional Chinese Medicine formulations in the treatment of hyperlipidemia (HLP). As effective ingredients of the drug pair, the effects and mechanisms of berberine and baicalin in the treatment of HLP in the form of components compatibility are still unclear. AIM OF THE STUDY: To explore the mechanism of the components compatibility of SR and CR in the treatment of HLP. MATERIALS AND METHODS: The HLP model was established by a high-fat diet. Serum biochemical indexes were detected. Transcriptomics and metabolomics were detected. RT-PCR and Western Blot were used to analyze the effect of RA on the expression of the Cyp4a family during the treatment of HLP. RESULTS: Berberine-baicalin (RA) has a good effect in the treatment of HLP. RA can significantly reduce the body weight and liver weight of HLP, reduce the levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL-C), and increase the level of high-density lipoprotein (HDL-C). Through transcriptomic analysis, RA significantly reversed the gene expression of Cyp4a10, Cyp4a12 b, Cyp4a31, and Cyp4a32 in cytochrome P450 family 4 subfamily a (Cyp4a) which related to fatty acid degradation in the liver of HLP mice. The results of fatty acid detection showed that RA could significantly regulate heptanoic acid, EPA, adrenic acid, DH-γ-linolenic acid, and DPA in the cecum of HLP mice. The Cyp4a family genes regulated by RA are closely related to a variety of fatty acids regulated by RA. RT-PCR confirmed that RA could regulate Cyp4a mRNA expression in HLP mice. WB also showed that RA can regulate the protein expression level of Cyp4a. CONCLUSION: The components compatibility of SR and CR can effectively improve the blood lipid level of HLP mice, its mechanism may be related to regulating Cyp4a gene expression and affecting fatty acid degradation, regulating the level of fatty acid metabolism in the body.

5.
J Dent ; 145: 104974, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38642823

RESUMEN

OBJECTIVES: This systematic review was aimed to evaluate the effect of non-surgical periodontal therapy (NSPT) on hemoglobin A1c (HbA1c) in periodontitis patients without diabetes mellitus (DM). DATA/SOURCES: The present systematic review and meta-analysis were performed through searching the following electronic databases: EMBASE, MEDLINE, Web of Science, Cochrane Library and Open GREY. Interventional studies of periodontitis patients without DM were investigated. HbA1c changes in these patients before and after NSPT were analyzed. Subgroup analysis and sensitivity analysis were employed to identify sources of heterogeneity. STUDY SELECTION: Three reviewers independently selected the eligible studies by screening the titles and abstract. Then, a full-text analysis was performed. The reasons for excluding studies were recorded. Any disagreements were settled by discussion with a fourth reviewer. All the four reviewers extracted and crosschecked the data, and disagreements were resolved by discussion. There are 21 case-series studies (self-controlled studies) and 1 non-randomized interventional studies (NRIs) were included. RESULTS: For periodontitis patients without DM, a total of 469 individuals from 22 studies were enrolled. The pooled analysis demonstrated that it was significantly changed in HbA1c levels at 3-month follow-up (0.16 with 95 % CI 0.04, 0.27; P = 0.008), and 6-month follow-up (0.17 % with 95 % CI 0.08, 0.27; P < 0.001) compared with baseline. Smoking, gender, experience of periodontal therapy and HbA1c value at baseline could be the sources of heterogeneity. CONCLUSIONS: NSPT is potentially beneficial for the management of HbA1c in periodontitis patients with high risks of DM. However, high-quality randomized controlled trials are still necessary to confirm these conclusions. CLINICAL SIGNIFICANCE: The systemic review evaluated the effect of NSPT on HbA1c in periodontitis patients without DM. The analysis may be beneficial to the management and control of the high risks of DM in periodontitis patients.


Asunto(s)
Hemoglobina Glucada , Periodontitis , Humanos , Hemoglobina Glucada/análisis , Periodontitis/terapia , Periodontitis/complicaciones , Periodontitis/sangre , Diabetes Mellitus/sangre , Raspado Dental , Resultado del Tratamiento
6.
Geohealth ; 8(4): e2023GH000888, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38638206

RESUMEN

The Multi-Threat Medical Countermeasure (MTMC) technique is crucial for developing common biochemical signaling pathways, molecular mediators, and cellular processes. This study revealed that the Nod-like receptor 3 (NLRP3) inflammasome pathway may be a significant contributor to the cytotoxicity induced by various organophosphorus pesticides (OPPs). The study demonstrated that exposure to six different types of OPPs (paraoxon, dichlorvos, fenthion, dipterex, dibrom, and dimethoate) led to significant cytotoxicity in BV2 cells, which was accompanied by increased expression of NLRP3 inflammasome complexes (NLRP3, ASC, Caspase-1) and downstream inflammatory cytokines (IL-1ß, IL-18), in which the order of cytotoxicity was dichlorvos > dipterex > dibrom > paraoxon > fenthion > dimethoate, based on the IC50 values of 274, 410, 551, 585, 2,158, and 1,527,566 µM, respectively. The findings suggest that targeting the NLRP3 inflammasome pathway could be a potential approach for developing broad-spectrum antitoxic drugs to combat multi-OPPs-induced toxicity. Moreover, inhibition of NLRP3 efficiently protected the cells against cytotoxicity induced by these six OPPs, and the expression of NLRP3, ASC, Caspase-1, IL-1ß, and IL-18 decreased accordingly. The order of NLRP3 affinity for OPPs was dimethoate > paraoxon > dichlorvos > dibrom > (fenthion and dipterex) based on K D values of 89.8, 325, 1,460, and 2,690 µM, respectively. Furthermore, the common molecular mechanism of NLRP3-OPPs was clarified by the presence of toxicity effector groups (benzene ring, nitrogen/oxygen-containing functional group); =O, -O-, or =S (active) groups; and combination residues (Gly271, Asp272). This finding provided valuable insights into exploring the common mechanisms of multiple threats and developing effective therapeutic strategies to prevent OPPs poisoning.

7.
Cell Mol Life Sci ; 81(1): 187, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38635081

RESUMEN

Idiopathic pulmonary fibrosis (IPF) poses significant challenges due to limited treatment options despite its complex pathogenesis involving cellular and molecular mechanisms. This study investigated the role of transient receptor potential ankyrin 1 (TRPA1) channels in regulating M2 macrophage polarization in IPF progression, potentially offering novel therapeutic targets. Using a bleomycin-induced pulmonary fibrosis model in C57BL/6J mice, we assessed the therapeutic potential of the TRPA1 inhibitor HC-030031. TRPA1 upregulation was observed in fibrotic lungs, correlating with worsened lung function and reduced survival. TRPA1 inhibition mitigated fibrosis severity, evidenced by decreased collagen deposition and restored lung tissue stiffness. Furthermore, TRPA1 blockade reversed aberrant M2 macrophage polarization induced by bleomycin, associated with reduced Smad2 phosphorylation in the TGF-ß1-Smad2 pathway. In vitro studies with THP-1 cells treated with bleomycin and HC-030031 corroborated these findings, highlighting TRPA1's involvement in fibrotic modulation and macrophage polarization control. Overall, targeting TRPA1 channels presents promising therapeutic potential in managing pulmonary fibrosis by reducing pro-fibrotic marker expression, inhibiting M2 macrophage polarization, and diminishing collagen deposition. This study sheds light on a novel avenue for therapeutic intervention in IPF, addressing a critical need in the management of this challenging disease.


Asunto(s)
Fibrosis Pulmonar Idiopática , Macrófagos , Canal Catiónico TRPA1 , Animales , Ratones , Acetanilidas , Bleomicina , Colágeno , Proteínas del Citoesqueleto , Ratones Endogámicos C57BL , Purinas , Canal Catiónico TRPA1/metabolismo
8.
Adv Mater ; : e2401856, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38529841

RESUMEN

Polymetallic phosphides exhibit favorable conductivities. A reasonable design of nano-metal-organic frame (MOF) composite morphologies and in situ introduction of polymetallic phosphides into the framework can effectively improve electrolyte penetration and rapid electron transfer. To address existing challenges, Ni, with a strong coordination ability with N, is introduced to partially replace Co in nano-Co-MOF composite. The hollow nanostructure is stabilized through CoNi bimetallic coordination and low-temperature controllable polymetallic phosphide generation rate. The Ni, Co, and P atoms, generated during reduction, effectively enhance electron transfer rate within the framework. X-ray absorption fine structure (XAFS) characterization results further confirm the existence of Ni-N, Ni-Ni, and Co-Co structures in the nanocomposite. The changes in each component during the charge-discharge process of the electrochemical reactions are investigated using in situ X-ray diffraction (XRD). Theoretical calculations further confirm that P can effectively improve conductivity. VZNPGC//MXene MSCs, constructed with active materials derived from the hollow nano MOF composites synthesized through the Ni2+ stabilization strategy, demonstrate a specific capacitance of 1184 mF cm-2, along with an energy density of 236.75 µWh cm-2 (power density of 0.14 mW cm-2). This approach introduces a new direction for the synthesis of highly conductive nano-MOF composites.

9.
Plants (Basel) ; 13(4)2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38502046

RESUMEN

In plants exposed to ultraviolet B radiation (UV-B; 280-315 nm), metabolic responses are activated, which reduce the damage caused by UV-B. Although several metabolites responding to UV-B stress have been identified in plants, the accumulation of these metabolites at different time points under UV-B stress remains largely unclear, and the transcription factors regulating these metabolites have not been well characterized. Here, we explored the changes in metabolites in rice after UV-B treatment for 0 h, 6 h, 12 h, and 24 h and identified six patterns of metabolic change. We show that the rice transcription factor OsbZIP18 plays an important role in regulating phenylpropanoid and flavonoid biosynthesis under UV-B stress in rice. Metabolic profiling revealed that the contents of phenylpropanoid and flavonoid were significantly reduced in osbzip18 mutants compared with the wild-type plants (WT) under UV-B stress. Further analysis showed that the expression of many genes involved in the phenylpropanoid and flavonoid biosynthesis pathways was lower in osbzip18 mutants than in WT plants, including OsPAL5, OsC4H, Os4CL, OsCHS, OsCHIL2, and OsF3H. Electrophoretic mobility shift assays (EMSA) revealed that OsbZIP18 bind to the promoters of these genes, suggesting that OsbZIP18 function is an important positive regulator of phenylpropanoid and flavonoid biosynthesis under UV-B stress. In conclusion, our findings revealed that OsbZIP18 is an essential regulator for phenylpropanoid and flavonoid biosynthesis and plays a crucial role in regulating UV-B stress responses in rice.

10.
Mol Med Rep ; 29(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38516772

RESUMEN

Remifentanil­induced hyperalgesia (RIH) is characterized by the emergence of stimulation­induced pain, including phenomena such as allodynia and thermal hyperalgesia following remifentanil infusion. As a sequence­specific DNA binding transcription factor, PAX6 positively and negatively regulates transcription and is expressed in multiple cell types in the developing and adult central nervous system. It was hypothesized that puerarin could relieve RIH via targeting PAX6 to regulate transcription of transient receptor potential cation channel subfamily V Member 1 (TRPV1). A total of 32 rats were randomly divided into five groups, namely control group, RI group, RI + 10 mg/kg puerarin group (RI + puerarin10), RI + 20 mg/kg puerarin group (RI + puerarin20), and RI + 40 mg/kg puerarin group (RI + puerarin40). Mechanical and thermal hyperalgesia were tested at ­24, 2, 6, 24 and 48 h after remifentanil infusion. Following the sacrifice of rats after the last behavioral test, western blot was used to detect the expression levels of TRPV1 in the tissues; Immunofluorescence staining and western blotting were used to detect the expression of PAX6 in the spinal cord. PharmMapper and JASPAR were used to predict the binding sites of puerarin/PAX6/TRPV1. Chromatin immunoprecipitation­PCR and dual luciferase reporter assay were used to verify the targeting relationship between PAX6 and TRPV1. Immunofluorescence was used to detect the expression levels of TRPV1 and p­NR2B. The results revealed that puerarin (10, 20, 40 mg/kg) dose­dependently reduced thermal and mechanical hyperalgesia from 2 to 48 h after remifentanil infusion. Remifentanil infusion remarkably stimulated the expression of phosphorylated (p­)NR2B. Nevertheless, the increased amount of p­NR2B by RIH was dose­dependently suppressed by puerarin in rats. In conclusion, puerarin was revealed to attenuate postoperative RIH via targeting PAX6 to regulate the transcription of TRPV1.


Asunto(s)
Hiperalgesia , Isoflavonas , Animales , Ratas , Hiperalgesia/inducido químicamente , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/genética , Isoflavonas/farmacología , Isoflavonas/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/etiología , Piperidinas/farmacología , Ratas Sprague-Dawley , Remifentanilo/efectos adversos , Factor de Transcripción PAX6/efectos de los fármacos , Factor de Transcripción PAX6/metabolismo , Canales Catiónicos TRPV/efectos de los fármacos , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo
11.
Heliyon ; 10(2): e24573, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38312597

RESUMEN

Ischemia-reperfusion injury (IRI) is a significant contributor to acute kidney injury (AKI) and is associated with substantial morbidity and mortality rates. In this study, we aimed to investigate the role of NAT10 and its ac4C RNA modification in IRI-induced renal injury. Our findings revealed that both the expression level of NAT10 and the RNA ac4C level in the kidneys were elevated in the IRI group compared to the sham group. Functionally, we observed that inhibition of NAT10 activity with Remodelin or the specific knockout of NAT10 in the kidney led to a significant attenuation of IRI-induced renal injury. Furthermore, in vitro experiments demonstrated that NAT10 inhibition and specific knockout of NAT10 in the kidney markedly suppressed global ac4C RNA modification, providing protection against hypoxia/reoxygenation-induced tubular epithelial cell injury and ferroptosis. Mechanistically, our study uncovered that NAT10 promoted ac4C RNA modification of NCOA4 mRNA, thereby enhancing its stability and contributing to IRI-induced ferroptosis in tubular epithelial cells (TECs). These findings underscore the potential of NAT10 and ac4C RNA modification as promising therapeutic targets for the treatment of AKI. Overall, our study sheds light on the critical involvement of NAT10 and ac4C RNA modification in the pathogenesis of IRI-induced renal injury, offering valuable insights for the development of novel AKI treatment strategies.

12.
J Clin Pharmacol ; 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38381330

RESUMEN

Perampanel (PER) is a new type of antiseizure medication used for partial or generalized seizures. However, the plasma concentration shows obvious individual variability in children. The present study aims to ascertain the effect of age, comedications, and cytochrome P450 (CYP) 3A4/5 polymorphisms on PER exposure in Chinese pediatric patients with epilepsy. Clinical data were retrospectively collected in a tertiary children's hospital medical records system from January 2021 to December 2022. The influence factors on the daily dose, plasma concentration, and concentration-to-dose ratio (CDR) of PER were investigated. A total of 135 pediatric patients with 178 blood samples were involved. With a median daily dose of 4.0 mg (interquartile range, 3.0-5.0 mg), the median plasma concentration was 409.4 ng/mL (interquartile range, 251.7-639.4 ng/mL). The CDR in patients aged less than 4 years was significantly decreased by 48.0% and 39.1% compared with those aged 4-11 years and 12 years or older, respectively. Enzyme inducers significantly decreased the CDR of PER by 34.5%, while valproic acid showed an increase of 71.7%. In addition, genotype CYP3A5*3/*3 carriers presented a significant increase of 21.5% compared to the CYP3A5*1/*3 expresser. No correlations were observed between the CDR and CYP3A4∗1G polymorphism. PER showed high variations in individual plasma concentrations. Age younger than 4 years, comedication with enzyme inducers or valproic acid, and possession of the CYP3A5*3 genotype potentially predicted PER exposure in pediatric patients with epilepsy.

13.
Mol Biotechnol ; 66(5): 1154-1164, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38253901

RESUMEN

To explore the potential mechanism of microRNA (miR)-181b-5p promoting the progression of thyroid cancer (TC) by targeting programmed cell death 4 (PDCD4). Analysis of miR-181b-5p and PDCD4 expression in TC was performed. The impact of miR-181b-5p and PDCD4 on proliferation, migration, invasion, and apoptosis of TC cells was examined. The binding relationship between miR-181b-5p and PDCD4 was predicted and verified. miR-181b-5p was up-regulated in TC, while PDCD4 was down-regulated. Down-regulating miR-181b-5p or up-regulating PDCD4 inhibited the proliferation, migration, and invasion of TC cells, and promoted cell apoptosis. PDCD4 was the downstream target of miR-181b-5p, and down-regulation of PDCD4 counteracted the inhibitory effect of down-regulation of miR-181b-5p on the proliferation, migration, and invasion of TC cells and the promoting effect on apoptosis. miR-181b-5p inhibits the proliferation, migration, and invasion of TC cells and promotes cell apoptosis by targeting PDCD4.


Asunto(s)
Proteínas Reguladoras de la Apoptosis , Apoptosis , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , MicroARNs , Proteínas de Unión al ARN , Neoplasias de la Tiroides , MicroARNs/genética , MicroARNs/metabolismo , Humanos , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/metabolismo , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proliferación Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Apoptosis/genética , Invasividad Neoplásica/genética , Masculino , Persona de Mediana Edad , Regulación hacia Abajo , Femenino
14.
J Colloid Interface Sci ; 659: 594-602, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38198936

RESUMEN

The development of a full-spectrum responsive photocatalytic germicide with excellent charge separation efficiency to harvest high antimicrobial efficacy is a key goal yet a challenging conundrum. Herein, graphitic carbon nitride nanosheet (PCNS)/Ti3C2Tx MXene/TiO2 (PMT) Z-scheme heterojunctions with robust interface contact were crafted by in situ interfacial engineering. The strong internal electrical field (IEF) from PCNS to TiO2, evinced by the Kelvin Probe Force Microscopy (KPFM) characterization, can obtain high charge separation efficiency with 73.99%, compared to Schottky junction PCNS/Ti3C2Tx (PM, 32.88%) and PCNS (17.70%). The Ti3C2Tx component can not only serve as a transfer pathway to accelerate the recombination of photoexcited electrons of TiO2 and holes of PCNS under the Ultraviolet-visible (UV-vis) light irradiation, but also replenish the photogenic electron concentrations to semiconductors in the near-infrared (NIR) light illumination. Meanwhile, the increased temperature due to the localized surface plasmon resonance (LSPR) can further boost the electronic activity to the generation of reactive oxygen species (ROS). Taken together, the PMT performs a high disinfection efficiency up to 99.40% under full solar spectrum illumination, 3.88 and 9.75 times higher than PCNS and TiO2, respectively, surpassing many reported Z-scheme heterojunctions. This work offers guidance for the design of Z-scheme heterojunction with the implanting of plasmons to secure excellent full-spectrum responsive photocatalytic sterilization performance.

15.
Bioorg Chem ; 143: 107055, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38185008

RESUMEN

Hydration, a secondary activity mediated by nitrilase, is a promising new pathway for amide production. However, low hydration activity of nitrilase or trade-off between hydration and catalytic activity hinders its application in the production of amides. Here, natural C-terminal-truncated wild-type nitrilase, mined from a public database, obtained a high-hydration activity nitrilase as a novel evolutionary starting point for further protein engineering. The nitrilase Nit-74 from Spirosoma linguale DSM 74 was successfully obtained and exhibited the highest hydration activity level, performing 50.7 % nicotinamide formation and 87.6 % conversion to 2 mM substrate 3-cyanopyridine. Steric hindrance of the catalytic activity center and the N-terminus of the catalytic cysteine residue helped us identify three key residues: I166, W168, and T191. Saturation mutations resulted in three single mutants that further improved the hydration activity of N-heterocyclic nitriles. Among them, the mutant T191S performed 72.7 % nicotinamide formation, which was much higher than the previously reported highest level of 18.7 %. Additionally, mutants I166N and W168Y exhibited a 97.5 % 2-picolinamide ratio and 97.7 % isonicotinamide ratio without any loss of catalytic activity, which did not indicate a trade-off effect. Our results expand the screening and evolution library of promiscuous nitrilases with high hydration activity for amide formation.


Asunto(s)
Aminohidrolasas , Cytophagaceae , Nitrilos , Pirimidinas , Triazoles , Nitrilos/química , Aminohidrolasas/genética , Aminohidrolasas/química , Aminohidrolasas/metabolismo , Amidas , Niacinamida , Especificidad por Sustrato
16.
Nanoscale ; 16(6): 2945-2954, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38236129

RESUMEN

In various domains spanning materials synthesis, chemical catalysis, life sciences, and energy materials, in situ transmission electron microscopy (TEM) methods exert a profound influence. These methodologies enable the real-time observation and manipulation of gas-phase and liquid-phase reactions at the nanoscale, facilitating the exploration of pivotal reaction mechanisms. Fundamental research areas like crystal nucleation, growth, etching, and self-assembly have greatly benefited from these techniques. Additionally, their applications extend across diverse fields such as catalysis, batteries, bioimaging, and drug delivery kinetics. However, the intricate nature of 'soft matter' presents a challenge due to the unique molecular properties and dynamic behavior of these substances that remain insufficiently understood. Investigating soft matter within in situ liquid-phase TEM settings demands further exploration and advancement compared to other research domains. This research harnesses the potential of in situ liquid-phase TEM technology while integrating deep learning methodologies to comprehensively analyze the quantitative aspects of soft matter dynamics. This study centers on diverse phenomena, encompassing surfactant molecule nucleation, block copolymer behavior, confinement-driven self-assembly, and drying processes. Furthermore, deep learning techniques are employed to precisely analyze Ostwald ripening and digestive ripening dynamics. The outcomes of this study not only deepen the understanding of soft matter at its fundamental level but also serve as a pivotal foundation for developing innovative functional materials and cutting-edge devices.

17.
New Phytol ; 241(6): 2558-2574, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38258425

RESUMEN

Salt stress negatively affects rice growth, development and yield. Metabolic adjustments contribute to the adaptation of rice under salt stress. Branched-chain amino acids (BCAA) are three essential amino acids that cannot be synthesized by humans or animals. However, little is known about the role of BCAA in response to salt stress in plants. Here, we showed that BCAAs may function as scavengers of reactive oxygen species (ROS) to provide protection against damage caused by salinity. We determined that branched-chain aminotransferase 2 (OsBCAT2), a protein responsible for the degradation of BCAA, positively regulates salt tolerance. Salt significantly induces the expression of OsBCAT2 rather than BCAA synthesis genes, which indicated that salt mainly promotes BCAA degradation and not de novo synthesis. Metabolomics analysis revealed that vitamin B5 (VB5) biosynthesis pathway intermediates were higher in the OsBCAT2-overexpressing plants but lower in osbcat2 mutants under salt stress. The salt stress-sensitive phenotypes of the osbcat2 mutants are rescued by exogenous VB5, indicating that OsBCAT2 affects rice salt tolerance by regulating VB5 synthesis. Our work provides new insights into the enzymes involved in BCAAs degradation and VB5 biosynthesis and sheds light on the molecular mechanism of BCAAs in response to salt stress.


Asunto(s)
Aminoácidos de Cadena Ramificada , Ácido Pantoténico , Humanos , Animales , Aminoácidos de Cadena Ramificada/metabolismo , Tolerancia a la Sal/genética , Metabolómica
18.
J Colloid Interface Sci ; 657: 811-818, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38081115

RESUMEN

Electrochemical water splitting is one of the most active areas of energy research, yet the benchmark electrocatalysts used for this area are based on expensive noble metals and transition metals, thus mainly reactions in alkaline solution. MOFs and halide perovskite are novel electrochemical catalysts but unstable in water basically. Here we report a study on composites of (NH2)-MIL-53(Al) MOFs and CBB halide perovskite (Cs3Bi2Br9), which exhibit obvious activity for overall electrochemical water splitting for long-term stability with little deactivation after 10 h in all pH solutions.

19.
J Chem Theory Comput ; 20(4): 1519-1537, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-37490766

RESUMEN

Bolapolyphiles constitute a versatile class of materials with a demonstrated potential to form a wide variety of complex ordered mesophases. In particular, cubic network phases (like the gyroid, primitive, and diamond phases) have been a target of many studies for their ability to create percolating 3D nanosized channels. In this study, molecular simulations are used to explore the phase behavior of bolapolyphiles containing a rigid rodlike core, associating hydrophilic core ends and a hydrophobic side chain with a multident architecture, i.e., where the branching pattern can vary from bident (two branches) to hexadent (six branches). Upon network phase formation, its skeleton is made up of "nodes" populated by the core ends and "struts" populated by the cores. It is shown that, by varying the side chain length, branching pattern, and attachment point to the core, one can alter the crowding around the cores and hence tune the nodal size and nodal valence (i.e., number of connecting struts) which lead to different types of network morphologies. For example, for a fixed total side chain length, having more branches generates a stronger crowding around the molecular core, driving them to form bundlelike domains with curvier interfaces that result in thinner struts. Also, attaching the lateral chain closer to one core end breaks the symmetry between the environments around the two core ends, leading to networks with bimodal nodal sizes. Importantly, since the characterization of (ordered or partially ordered) network phases is challenging given the potential incompatibilities between the simulation box size with the structure's space group periodic symmetry and the effect of morphological defects, a detailed framework is presented to analyze and fully characterize the unit cell parameters and structure factor of such systems.

20.
Angew Chem Int Ed Engl ; 63(3): e202316973, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38051287

RESUMEN

This work reports that a low-temperature thermal calcination strategy was adopted to modulate the electronic structure and attain an abundance of surface-active sites while maintaining the crystal morphology. All the experiments demonstrate that the new photocatalyst nano MIL-125(Ti)-250 obtained by thermal calcination strategy has abundant Ti3+ induced by oxygen vacancies and high specific surface area. This facilitates the adsorption and activation of N2 molecules on the active sites in the photocatalytic nitrogen fixation. The photocatalytic NH3 yield over MIL-125(Ti)-250 is enhanced to 156.9 µmol g-1 h-1 , over twice higher than that of the parent MIL-125(Ti) (76.2 µmol g-1 h-1 ). Combined with density function theory (DFT), it shows that the N2 adsorption pattern on the active sites tends to be from "end-on" to "side-on" mode, which is thermodynamically favourable. Moreover, the electrochemical tests demonstrate that the high atomic ratio of Ti3+ /Ti4+ can enhance carrier separation, which also promotes the efficiency of photocatalytic N2 fixation. This work may offer new insights into the design of innovative photocatalysts for various chemical reduction reactions.

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