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2.
Front Bioeng Biotechnol ; 12: 1418493, 2024.
Article de Anglais | MEDLINE | ID: mdl-39108594

RÉSUMÉ

During invisalign treatment, as salivary proteins or glycoproteins fill the space between the teeth and the aligners, they can easily adhere to the teeth, forming an acquired cellular film on which bacteria are highly susceptible to colonizing, which in turn leads to the development of enamel white staining lesions (WSLs), one of the major complications of orthodontic treatment. Inhibiting the activity of cariogenic bacteria while promoting the remineralization of demineralized enamel is the key to preventing and treating WSLs. Currently, the drug commonly used in clinical practice for the treatment of WSLs is silver diamine fluoride, which, although it has both antimicrobial and remineralizing effects, suffers from problems such as pulpal irritation and tooth discoloration. In this study, based on the principle of coordination chemistry, copper ions and plant polyphenol tannins were assembled on invisible orthodontic aligners to form a metal-phenol network coating (TA-Cu MPNs), and zwitterionic sulfonamethyldopamine was introduced for bionic mineralization to obtain the multifunctional coating TA-Cu MPNs@ZDS@CaP (TZC). The coating exhibits acid-responsive release of Ca2+ and PO4 3-, and the decomposed CaP layer can be regenerated by a simple dipping method. The TZC coating strongly inhibits common cariogenic bacteria and their biofilms. In addition, the results of the in vitro mineralization experiment show that TZC-coated invisible orthodontic aligner treatment of demineralized enamel has significant remineralization effects. It is worth mentioning that the constructed coating has a durable antibacterial effect and can meet the service cycle of invisible orthodontic aligners. This study provides theoretical and experimental bases for the prevention or treatment of WSLs in invisible orthodontic treatment.

3.
Front Bioeng Biotechnol ; 12: 1421887, 2024.
Article de Anglais | MEDLINE | ID: mdl-39081333

RÉSUMÉ

Acidic bacterial biofilms-associated enamel white spot lesions (WSLs) are one of the hallmarks of early caries, causing demineralization and decomposition of dental hard tissues. Therefore, to effectively prevent and treat WSLs, it is important to inhibit the activity of cariogenic bacteria while promoting the remineralization of demineralized enamel. Amorphous calcium phosphate (ACP) favors hard tissue remineralization due to its biological activity and ability to release large amounts of Ca2+ and PO4 3-. However, ACP-based biomineralization technology is not effective due to its lack of antimicrobial properties. Here, carboxymethyl chitosan (CMCS) was employed as a reducing agent and stabilizer, and dual-functional nanohybrids CMCS/AuNPs/ACP with biofilm resistance and mineralization properties were successfully synthesized. The addition of AuNPs enhances the antimicrobial activity and participates in regulating the formation of hydroxyapatite (HAp). The nanohybrids exhibited significant destructive effects against cariogenic bacteria and their biofilms and showed bactericidal activity under bacteria-induced acidic conditions. More importantly, this nanohybrids showed superior results in promoting the remineralization of demineralized enamel, compared to fluoride and CMCS/ACP in vitro. The CMCS/AuNPs/ACP nanohybrids not only reverse the cariogenic microenvironment at the microbial level, but also promote self-repairing of enamel WSLs regarding the microstructure. The present work offers a theoretical and experimental basis for using the CMCS/AuNPs/ACP nanohybrids as a potential dual-functional agent for the clinical treatment of enamel WSLs.

4.
IET Nanobiotechnol ; 2024: 4391833, 2024.
Article de Anglais | MEDLINE | ID: mdl-38863970

RÉSUMÉ

The massive growth of various microorganisms on the orthodontic bracket can form plaques and cause diseases. A novel amine-terminated hyperbranched zirconium-polysiloxane (HPZP) antimicrobial coating was developed for an orthodontic stainless steel tank (SST). After synthesizing HPZP and HPZP-Ag coatings, their structures were characterized by nuclear magnetic resonance spectroscopy, scanning electron microscopy, thickness measurement, contact angle detection, mechanical stability testing, and corrosion testing. The cell toxicity of the two coatings to human gingival fibroblasts (hGFs) and human oral keratinocytes (hOKs) was detected by cell counting kit eight assays, and SST, HPZP@SST, and HPZP-Ag@SST were cocultured with Staphylococcus aureus, Escherichia coli, and Streptococcus mutans for 24 hr to detect the antibacterial properties of the coatings, respectively. The results show that the coatings are about 10 µm, and the water contact angle of HPZP coating is significantly higher than that of HPZP-Ag coating (P < 0.01). Both coatings can be uniformly and densely distributed on SST and have good mechanical stability and corrosion resistance. The cell counting test showed that HPZP coating and HPZP-Ag coating were less toxic to cells compared with SST, and the toxicity of HPZP-Ag coating was greater than that of HPZP coating, with the cell survival rate greater than 80% after 72 hr cocultured with hGFs and hOKs. The antibacterial test showed that the number of bacteria on the surface of different materials was ranked from small to large: HPZP@SST < HPZP-Ag@SST < SST and 800 µg/mL HPZP@SST showed a better bactericidal ability than 400 µg/mL after cocultured with S. aureus, E. coli, and S. mutans, respectively (all P < 0.05). The results showed that HPZP coating had a better effect than HPZP-Ag coating, with effective antibacterial and biocompatible properties, which had the potential to be applied in orthodontic process management.


Sujet(s)
Antibactériens , Matériaux revêtus, biocompatibles , Brackets orthodontiques , Siloxanes , Acier inoxydable , Zirconium , Acier inoxydable/composition chimique , Acier inoxydable/pharmacologie , Matériaux revêtus, biocompatibles/composition chimique , Matériaux revêtus, biocompatibles/pharmacologie , Humains , Antibactériens/pharmacologie , Antibactériens/composition chimique , Brackets orthodontiques/microbiologie , Zirconium/composition chimique , Zirconium/pharmacologie , Siloxanes/composition chimique , Siloxanes/pharmacologie , Fibroblastes/effets des médicaments et des substances chimiques , Test de matériaux , Amines/composition chimique , Amines/pharmacologie , Staphylococcus aureus/effets des médicaments et des substances chimiques , Propriétés de surface , Escherichia coli/effets des médicaments et des substances chimiques , Kératinocytes/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Gencive/cytologie , Gencive/effets des médicaments et des substances chimiques
6.
Int J Biol Macromol ; 273(Pt 2): 133161, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38885863

RÉSUMÉ

Eucalyptus was pretreated with diethylene glycol catalyzed by 0.02 mol/L CrCl3 for 10 min, resulting in 91 % delignification and 98 % cellulose recovery, with trace fermentation inhibitors generated. After the mild pretreatment, the accessibility and affinity of cellulase to eucalyptus was enhanced, especially since enzyme adsorption rate increased by 1.6-fold. Therefore, glucose yield of pretreated eucalyptus was 7.9-fold higher than that of untreated eucalyptus after hydrolyzed 48 h, in which the maximum glucose concentration reached 62 g/L from eucalyptus by adding Tween 80. According to the characterization analysis, the structure of the eucalyptus lignin-carbohydrate complexes structure was destroyed during the pretreatment, while lignin fragments was likely reacted with diethylene glycol to form the stabilized aromatic ethers. Moreover, the extracted Deg-lignin exhibited better performances than commercial alkali lignin such as higher fluorescence intensity, less negative surface charge, and lower particle size. The mild pretreatment method with diethylene glycol and CrCl3 provided a promising approach for co-production of fermentable sugars and high activity lignin from lignocellulosic biomass.


Sujet(s)
Éthylène glycols , Eucalyptus , Fermentation , Lignine , Eucalyptus/composition chimique , Lignine/composition chimique , Éthylène glycols/composition chimique , Hydrolyse , Glucose/métabolisme , Glucose/composition chimique , Sucres/composition chimique , Sucres/métabolisme , Cellulase/métabolisme , Cellulase/composition chimique , Biomasse
7.
Virology ; 595: 110084, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38692132

RÉSUMÉ

Duck Tembusu virus (DTMUV) belongs to the Flaviviridae family and mainly infects ducks. The genome of DTMUV is translated into a polyprotein, which is further cleaved into several protein by viral NS2B3 protease and host proteases. Crucially, the cleavage of the NS2A/2B precursor during this process is essential for the formation of replication complexes and viral packaging. Previous research has demonstrated that alanine mutations in NS2A/2B (P1P1' (AA)) result in an attenuated strain (rDTMUV-NS2A/2B-P1P1' (AA)) by disrupting NS2A/2B cleavage. In this study, we investigate the effects of the P1P1' (AA) mutation on the viral life cycle and explore compensatory mutations in rDTMUV-NS2A/2B-P1P1' (AA). Infected ducklings exhibit similar body weight gain and viral tissue loads to DTMUV-WT. Compensatory mutations E-M349E and P1(T) emerge, restoring proliferation levels to those of rDTMUV-WT. Specifically, E-M349E enhances viral packaging, while P1(T) reinstates NS2A/2B proteolysis in vitro. Thus, our findings reveal novel compensatory sites capable of restoring the attenuated DTMUV during polyprotein cleavage and packaging.


Sujet(s)
Canards , Flavivirus , Maladies de la volaille , Protéines virales non structurales , Assemblage viral , Réplication virale , Animaux , Canards/virologie , Protéines virales non structurales/génétique , Protéines virales non structurales/métabolisme , Flavivirus/génétique , Flavivirus/physiologie , Maladies de la volaille/virologie , Infections à flavivirus/virologie , Mutation
8.
RSC Adv ; 14(21): 15008-15020, 2024 May 02.
Article de Anglais | MEDLINE | ID: mdl-38720974

RÉSUMÉ

Enamel white spot lesions (WSLs) are usually caused by the dissolution of minerals (mainly calcium and phosphate) on the tooth surface due to the acidic environment in the oral cavity. Without timely intervention, WSLs may lead to white spots or a sense of transparency on the tooth surface, and even the formation of dental caries (tooth decay) in severe cases. The key to preventing and treating WSLs is inhibiting the activity of acid-producing bacteria and promoting the remineralization of demineralized enamel. In this study, the network structure formed by sodium tripolyphosphate (TPP) cross-linked chitosan was used to stabilize calcium phosphate, and the multifunctional nanocomposite was constructed by integrating antibacterial components of traditional Chinese medicine, honokiol nanoparticles (HK-NPs) and sodium fluoride to achieve the purpose of resisting cariogenic bacteria and remineralizing with sustained release of calcium and phosphate ions. Notably, we enhanced the remineralization effect of nanocomposites with the help of functional nanocoatings inspired by the mussel biomimetic coating. The experimental results show that the synergistic remineralization effect of nanocomposite and nanocoating is better than that of a single strategy. This multi-prong treatment strategy provides the theoretical and experimental basis for the clinical prevention and treatment of WSLs.

9.
Hum Cell ; 37(4): 1120-1131, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38625505

RÉSUMÉ

Cancer-associated fibroblasts (CAFs) can promote the crosstalk between cancer cells and tumor microenvironment by exosomes. METTL3-mediated N6-methyladenine (m6A) modification has been proved to promote the progression of non-small cell lung cancer (NSCLC). Here, we focused on the impacts of CAFs-derived exosomes and METTL3-mediated m6A modification on NSCLC progression. Functional analyses were conducted using Cell Counting Kit-8, EdU, colony formation, sphere formation and transwell assays, respectively. Glutamine metabolism was evaluated by detecting glutamate consumption, and the production of intercellular glutamate and α-ketoglutarate (α-KG). qRT-PCR and western blotting analyses were utilized to measure the levels of genes and proteins. Exosomes were isolated by kits. The methylated RNA immunoprecipitation assay detected the m6A modification profile of Amino acid transporter LAT1 (SLC7A5) mRNA. The NSCLC mouse model was established to conduct in vivo experiments. We found that CAFs promoted the proliferation, invasion, stemness and glutaminolysis in NSCLC cells. METTL3 was enriched in CAFs and was packaged into exosomes. After knockdown of METTL3 in CAF exosomes, it was found the oncogenic effects of CAFs on NSCLC cells were suppressed. CAFs elevated m6A levels in NSCLC cells. Mechanistically, exosomal METTL3-induced m6A modification in SLC7A5 mRNA and stabilized its expression in NSCLC cells. Moreover, SLC7A5 overexpression abolished the inhibitory effects of exosomal METTL3-decreased CAFs on NSCLC cells. In addition, METTL3 inhibition in CAF exosomes impeded NSCLC growth in vivo. In all, CAFs-derived exosomal METTL3 promoted the proliferation, invasion, stemness and glutaminolysis in NSCLC cells by inducing SLC7A5 m6A modification.


Sujet(s)
Fibroblastes associés au cancer , Carcinome pulmonaire non à petites cellules , Prolifération cellulaire , Exosomes , Glutamine , Tumeurs du poumon , Methyltransferases , Invasion tumorale , Animaux , Humains , Souris , Adénosine/analogues et dérivés , Adénosine/métabolisme , Fibroblastes associés au cancer/métabolisme , Fibroblastes associés au cancer/anatomopathologie , Carcinome pulmonaire non à petites cellules/anatomopathologie , Carcinome pulmonaire non à petites cellules/génétique , Carcinome pulmonaire non à petites cellules/métabolisme , Lignée cellulaire tumorale , Prolifération cellulaire/génétique , Modèles animaux de maladie humaine , Exosomes/métabolisme , Exosomes/génétique , Expression des gènes/génétique , Glutamine/métabolisme , Transporteur-1 d'acides aminés neutres à longue chaîne/métabolisme , Transporteur-1 d'acides aminés neutres à longue chaîne/génétique , Transporteur-1 d'acides aminés neutres à longue chaîne/physiologie , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/génétique , Tumeurs du poumon/métabolisme , Methyltransferases/métabolisme , Methyltransferases/génétique , Methyltransferases/physiologie , Invasion tumorale/génétique , Microenvironnement tumoral/génétique
10.
J Assist Reprod Genet ; 41(5): 1403-1416, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38536597

RÉSUMÉ

PURPOSE: Preeclampsia (PE) is a vascular remodeling disorder cloesly linked to trophoblast dysfunction, involving defects in their proliferation, migration, and apoptosis. Maternal exosomal microRNAs (miRNAs) have been reported to play pivotal roles in the development of PE. However, the mechanism underlying the role of maternal exosomes in trophoblast dysfunction regarding the development of PE is poorly understood. METHODS: Plasma exosomes from maternal peripheral blood were collected from pregnant women with PE and from those with normal pregnancy. Bioinformatics analysis was used to identify significantly differentially expressed miRNAs under these two conditions. The expression of the miR-3198 gene in plasma exosomes was detected using quantitative real-time polymerase chain reaction. Dual luciferase reporter assay was used to confirm binding of miR-3198 and 3'UTR region of WNT3. Cell proliferation was examined using the Cell Count Kit-8 and EdU assays, and flow cytometry was performed to detect apoptosis and cell cycle. Changes in cell migration were examined using transwell and scratch assays. RESULTS: Patients with PE showed decreased expression of plasma-derived exosomal miR-3198. The proliferation and migration abilities of HTR-8/SVneo and primary human trophoblast cells were both improved when cocultured with miR-3198-rich exosomes. Exposure to miR-3198-enriched exosomes facilitated cell cycle progression but reduced apoptosis in HTR-8/SVneo cells. Notably, overexpression of miR-3198 partially prevented the inhibitory effects of WNT3 on proliferation and migration in HTR-8/SVneo cells. CONCLUSION: Exosomal miR-3198 in the maternal peripheral blood may regulate the biological functions of trophoblasts by targeting WNT3 and influence the development of diseases of placental origin.


Sujet(s)
Apoptose , Mouvement cellulaire , Prolifération cellulaire , Exosomes , microARN , Pré-éclampsie , Trophoblastes , Humains , Pré-éclampsie/génétique , Pré-éclampsie/anatomopathologie , Femelle , Exosomes/génétique , Exosomes/métabolisme , Trophoblastes/métabolisme , Trophoblastes/anatomopathologie , microARN/génétique , Grossesse , Mouvement cellulaire/génétique , Prolifération cellulaire/génétique , Adulte , Apoptose/génétique , Protéine Wnt3/génétique , Protéine Wnt3/métabolisme
11.
J Hazard Mater ; 469: 133936, 2024 May 05.
Article de Anglais | MEDLINE | ID: mdl-38479139

RÉSUMÉ

Water quality in the Yangtze River Basin (YRB) has received considerable attention because it supplies water to 400 million people. However, the trends, sources, and risks associated with heavy metals (HMs) in water of centralized drinking water sources (CDWSs) in the YRB region are not well understood due to the lack of high-frequency, large-scale monitoring data. Moreover, research on the factors affecting the transportation of HMs in natural water are limited, all of which significantly reduce the effectiveness of CDWSs management. Therefore, this study utilized data on 11 HMs and water quality from 114 CDWSs, covering 71 prefecture-level cities (PLC) in 15 provinces (cities), to map unprecedented geospatial distribution of HMs in the YRB region and examine their concentrations in relation to water chemistry parameters. The findings revealed that the frequency of detection (FOD) of 11 HMs ranged from 28.59% (Hg) to 99.64% (Ba). The mean concentrations are ranked as follows: Ba (40.775 µg/L) > B (21.866 µg/L) > Zn (5.133 µg/L) > V (2.668 µg/L) > Cu (2.049 µg/L) > As (1.989 µg/L) > Mo (1.505 µg/L) > Ni (1.108 µg/L) > Sb (0.613 µg/L) > Pb (0.553 µg/L) > Hg (0.002 µg/L). Concentrations of Zn, As, Hg, Pb, Mo, Sb, Ni, and Ba exhibited decreasing trends from 2018 to 2022. Human activities, including industrial and agricultural production, have led to higher pollution levels in the midstream and downstream of the river than in its upstream. Additionally, the high concentrations of Ba and B are influenced by natural geological factors. Anion concentrations and nutrient levels, play a significant role in the transport of HMs in water. Probabilistic health risk assessment indicates that As, Ba, and Sb pose a potential carcinogenic risk. Additionally, non-carcinogenic risk to children under extreme conditions should also be considered.

12.
Poult Sci ; 103(4): 103498, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38364609

RÉSUMÉ

Duck plague (DP) is one of the contagious diseases caused by Duck plague virus (DPV), which is a serious threat to the development of duck farming. Us3 is a PKA-like protein kinase in alphaherpesvirus, which can regulate the biological functions of many viral proteins, but whether Us3 regulates pUL48 protein has not been reported. In this paper, Western Blot, qRT-PCR, dual luciferase reporter system and Co-IP were used to investigate the relationship between pUL48 and Us3. The results showed that: 1) pUL48 interacted with Us3 at 138-256aa through its DBD region. 2) Us3 enhanced the protein expression of pUL48 in a dose-dependent manner. 3) Us3 promoted the mRNA level of pUL48 by activating its promoter activity. 4) Us3 inhibited the transcriptional activation function of pUL48. The results can provide scientific data for perfecting and supplementing the function of alpha herpesvirus Us3 and pUL48.


Sujet(s)
Poulets , Canards , Mardivirus , Animaux , Canards/métabolisme , Poulets/métabolisme , Protéines virales/génétique , Protéines virales/métabolisme , Protein kinases/génétique
13.
Vet Res ; 55(1): 2, 2024 Jan 03.
Article de Anglais | MEDLINE | ID: mdl-38172999

RÉSUMÉ

During the replication process, the herpesvirus genome forms the head-to-tail linked concatemeric genome, which is then cleaved and packaged into the capsid. The cleavage and packing process is carried out by the terminase complex, which specifically recognizes and cleaves the concatemeric genome. This process is governed by a cis-acting sequence in the genome, named the a sequence. The a sequence and genome cleavage have been described in some herpesviruses, but it remains unclear in duck plague virus. In this study, we analysed the location, composition, and conservation of a sequence in the duck plague virus genome. The structure of the DPV genome has an a sequence of (DR4)m-(DR2)n-pac1-S termini (32 bp)-L termini (32 bp)-pac2, and the length is 841 bp. Direct repeat (DR) sequences are conserved in different DPV strains, but the number of DR copies is inconsistent. Additionally, the typical DR1 sequence was not found in the DPV a sequence. The Pac1 and pac2 motifs are relatively conserved between DPV and other herpesviruses. Cleavage of the DPV concatemeric genome was detected, and the results showed that the DPV genome can form a concatemer and is cleaved into a monomer at a specific site. We also established a sensitive method, TaqMan dual qRT‒PCR, to analyse genome cleavage. The ratio of concatemer to total viral genome was decreased during the replication process. These results will be critical for understanding the process of DPV genome cleavage, and the application of TaqMan dual qRT‒PCR will greatly facilitate more in-depth research.


Sujet(s)
Canards , Herpesviridae , Animaux , Canards/génétique , ADN viral/composition chimique , Séquence nucléotidique , Séquences répétées d'acides nucléiques , Herpesviridae/génétique , Génome viral
14.
Endocr Pract ; 30(3): 231-238, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38086525

RÉSUMÉ

OBJECTIVE: The main purpose of this study was to explore the diagnostic performance of the Ca∗Cl/P ratio for primary hyperparathyroidism (PHPT), especially normocalcaemic PHPT (NPHPT), to assist health care providers in making reliable and rapid clinical identifications. METHODS: From January 1, 2013, to March 31, 2023, 230 PHPT patients, including 65 with NPHPT and 230 sex- and age-matched controls, were enrolled in this retrospective study. Differences between hypercalcaemic PHPT (HPHPT) and NPHPT and between them and their respective controls were analyzed. The diagnostic accuracy of the Ca∗Cl/P ratio, Ca/P ratio, Cl/P ratio and albumin-corrected calcium was assessed by the area under the receiver operating characteristic curve. RESULTS: Compared with corresponding controls, NPHPT and HPHPT patients both had significantly higher Ca ∗ Cl/P ratios (271.64 ± 51.74 vs 192.71 ± 26; 419.91 ± 139.11 vs 199.14 ± 36.75, P < .001). In the overall cohort, the ROC-AUC of the Ca∗Cl/P ratio (0.964, 95% CI = 0.943-0.979) for diagnosis of PHPT patients was superior to albumin-corrected calcium (0.959, 95% CI = 0.934-0.973), the Ca/P ratio (0.956, 95% CI = 0.934-0.973), and the Cl/P ratio (0.923, 95% CI = 0.895-0.946). A Ca ∗ Cl/P ratio above 239.17 mmol/L, with sensitivity (0.952), specificity (0.922), PPV (0.924), NPV (0.951) and accuracy (0.937), can distinguish PHPT patients from healthy individuals. Furthermore, the Ca ∗ Cl/P ratio yielded a sensitivity of 0.831, specificity of 0.938, PPV of 0.931, NPV of 0.847 and accuracy of 0.885 for NPHPT. CONCLUSION: The Ca∗Cl/P ratio provides excellent diagnostic power for diagnosis of PHPT, especially NPHPT.


Sujet(s)
Hypercalcémie , Hyperparathyroïdie primitive , Humains , Calcium , Hyperparathyroïdie primitive/diagnostic , Études rétrospectives , Albumines , Hormone parathyroïdienne
15.
Appl Environ Microbiol ; 90(1): e0135023, 2024 01 24.
Article de Anglais | MEDLINE | ID: mdl-38084999

RÉSUMÉ

Manganese (Mn) is an essential element for bacteria, but the overload of manganese is toxic. In a previous study, we showed that the cation diffusion facilitator protein MetA and the resistance-nodulation-division efflux pump MetB are responsible for Mn efflux in the bacterial pathogen Riemerella anatipestifer CH-1. However, whether this bacterium encodes additional manganese efflux proteins is unclear. In this study, we show that R. anatipestifer CH-1 encodes a tellurium resistance C (TerC) family protein with low similarity to other characterized TerC family proteins. Compared to the wild type (WT), the terC mutant of R. anatipestifer CH-1 (∆terC) is sensitive to Mn(II) intoxication. The ability of TerC to export manganese is higher than that of MetB but lower than that of MetA. Consistently, terC deletion (∆terC) led to intracellular accumulation of Mn2+ under excess manganese conditions. Further study showed that ∆terC was more sensitive than the WT to the oxidant hypoclorite but not to hydrogen peroxide. Mutagenesis studies showed that the mutant at amino acid sites of Glu116 (E116), Asp122 (D122), Glu245 (E245) Asp248 (D248), and Asp254 (D254) may be involved in the ability of TerC to export manganese. The transcription of terC was upregulated under excess manganese and downregulated under iron-limited conditions. However, this was not dependent on the manganese metabolism regulator MetR. In contrast to a strain lacking the manganese efflux pump MetA or MetB, the terC mutant is attenuated in virulence in a duckling model of infection due to increased sensitivity to duck serum. Finally, comparative analysis showed that homologs of TerC are distributed across the bacterial kingdom, suggesting that TerC exerts a conserved manganese efflux function.IMPORTANCERiemerella anatipestifer is a notorious bacterial pathogen of ducks and other birds. In R. anatipestifer, the genes involved in manganese efflux have not been completely identified, although MetA and MetB have been identified as two manganese exporters. Additionally, the function of TerC family proteins in manganese efflux is controversial. Here, we demonstrated that a TerC family protein helps prevent Mn(II) intoxication in R. anatipestifer and that the ability of TerC to export manganese is intermediate compared to that of MetA and MetB. Sequence analysis and mutagenesis studies showed that the conserved key amino sites of TerC are Glu116, Asp122, Glu245, Asp248, and Asp254. The transcription of terC was regulated by manganese excess and iron limitation. Finally, we show that TerC plays a role in the virulence of R. anatipestifer due to the increased sensitivity to duck serum, rather than the increased sensitivity to manganese. Taken together, these results expand our understanding of manganese efflux and the pathogenic mechanisms of R. anatipestifer.


Sujet(s)
Infections à Flavobacteriaceae , Maladies de la volaille , Riemerella , Animaux , Virulence/génétique , Protéines bactériennes/génétique , Manganèse/métabolisme , Tellure/métabolisme , Riemerella/génétique , Canards/microbiologie , Fer/métabolisme , Maladies de la volaille/microbiologie , Infections à Flavobacteriaceae/microbiologie
16.
Small ; 20(22): e2308568, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38126907

RÉSUMÉ

In this work, cyano contained g-C3N4 comodified by In2S3 and polypyrrole (C≡N─CN/IS/Ppy) materials are synthesized for the photocatalytic production of H2O2 and photocatalysis-self-Fenton reaction for highly efficient degradation of metronidazole. The results from UV-vis spectrophotometry, surface photovoltage, and Kelvin probe measurements reveal the promoted transport and separation efficiency of photoinduced charges after the introduction of In2S3 and Ppy in the heterojunction. The existence of a built-in electric field accelerates the photoinduced charge separation and preserves the stronger oxidation ability of holes at the valence band of C≡N─CN. Linear sweep voltammetry measurements, zeta potential analyzations, nitroblue tetrazolium determination, and other measurements show that Ppy improves the conversion ratio of •O2 - to H2O2 and the utilization ratio of •O2 -, as well as suppresses decomposition of H2O2. Accordingly, the H2O2 evolution rate produced via a two-step single-electron reduction reaction reaches almost 895 µmol L-1 h-1, a value 80% and 7.2-fold higher than those obtained with C≡N─CN/IS and C≡N─CN, respectively. The metronidazole removal rate obtained via photocatalysis-self-Fenton reaction attains 83.7% within 120 minutes, a value much higher than that recorded by the traditional Fenton method. Overall, the proposed synthesis materials and route look promising for the H2O2 production and organic pollutants degradation.

18.
Appl Environ Microbiol ; 89(12): e0130823, 2023 12 21.
Article de Anglais | MEDLINE | ID: mdl-38038982

RÉSUMÉ

IMPORTANCE: Riemerella anatipestifer (RA) is a notorious duck pathogen, characterized by a multitude of serotypes that exhibit no cross-reaction with one another. Moreover, RA is resistant to various antibacterial agents. Consequently, understanding the mechanisms behind resistance and identifying potential targets for drug development have become pressing needs. In this study, we show that the two TolC proteins play a role in the resistance to different drugs and metals and in the virulence. The results suggest that TolCA has a wider range of efflux substrates than TolCB. Except for gentamicin, neither TolCA nor TolCB was involved in the efflux of the other tested antibiotics. Strikingly, TolCA but not TolCB enhanced the frequency of resistance-conferring mutations. Moreover, TolCA was involved in RA virulence. Given its conservation in RA, TolCA has potential as a drug target for the development of therapeutics against RA infections.


Sujet(s)
Infections à Flavobacteriaceae , Maladies de la volaille , Riemerella , Animaux , Virulence/génétique , Riemerella/métabolisme , Canards/microbiologie , Facteurs de virulence/génétique , Métaux/métabolisme , Infections à Flavobacteriaceae/microbiologie , Maladies de la volaille/microbiologie , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme
19.
Future Oncol ; 19(30): 2055-2073, 2023 Sep.
Article de Anglais | MEDLINE | ID: mdl-37823367

RÉSUMÉ

Androgen deprivation therapy is a common treatment method for metastatic prostate cancer through lowering androgen levels; however, this therapy frequently leads to the development of castration-resistant prostate cancer (CRPC). This is attributed to the activation of the androgen receptor (AR) signaling pathway. Current treatments targeting AR are often ineffective mostly due to AR gene overexpression and mutations, as well as the presence of splice variants that accelerate CRPC progression. Thus there is a critical need for more specific medication to treat CRPC. Small interfering RNAs have shown great potential as a targeted therapy. This review discusses prostate cancer progression and the role of AR signaling in CRPC, and proposes siRNA-based targeted therapy as a promising strategy for CRPC.


Sujet(s)
Tumeurs prostatiques résistantes à la castration , Mâle , Humains , Tumeurs prostatiques résistantes à la castration/thérapie , Tumeurs prostatiques résistantes à la castration/traitement médicamenteux , Récepteurs aux androgènes/génétique , Récepteurs aux androgènes/métabolisme , Androgènes , Antagonistes des androgènes/usage thérapeutique , Petit ARN interférent/génétique , Petit ARN interférent/usage thérapeutique , Transduction du signal
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