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1.
Water Res ; 257: 121695, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38723352

RESUMO

Wolframite (FeWO4), a typical polyoxometalate, serves as an auspicious candidate for heterogeneous catalysts, courtesy of its high chemical stability and electronic properties. However, the electron-deficient surface-active Fe species in FeWO4 are insufficient to cleave H2O2 via Fe redox-mediated Fenton-like catalytic reaction. Herein, we doped Sulfur (S) atom into FeWO4 catalysts to refine the electronic structure of FeWO4 for H2O2 activation and sulfamethoxazole (SMX) degradation. Furthermore, spin-state reconstruction on S-doped FeWO4 was found to effectively refine the electronic structure of Fe in the d orbital, thereby enhancing H2O2 activation. S doping also accelerated electron transfer during the conversion of sulfur species, promoting the cycling of Fe(III) to Fe(II). Consequently, S-doped FeWO4 bolstered the Fenton-like reaction by nearly two orders of magnitude compared to FeWO4. Significantly, the developed S-doped FeWO4 exhibited a remarkable removal efficiency of approximately 100% for SMX within 40 min in real water samples. This underscores its extensive pH adaptability, robust catalytic stability, and leaching resistance. The matrix effects of water constituents on the performance of S-doped FeWO4 were also investigated, and the results showed that a certain amount of Cl-, SO42-, NO3-, HCO3- and PO43- exhibited negligible effects on the degradation of SMX. Theoretical calculations corroborate that the distinctive spin-state reconstruction of Fe center in S-doped FeWO4 is advantageous for H2O2 decomposition. This discovery offers novel mechanistic insight into the enhanced catalytic activity of S doping in Fenton-like reactions and paves the way for expanding the application of FeWO4 in wastewater treatment.

2.
Food Chem ; 452: 139546, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38744137

RESUMO

The purpose of the study was to illustrate the roles of three primary indexes, namely sunlight, ventilation and stirring, in the 'bask in sunlight and dewed at night' technique on the quality of shrimp paste, through a laboratory-scale design. The results showed that changes in the post-ripening fermentation conditions, especially sunlight, was instrumental in the physicochemical properties of the shrimp paste. E-nose and SPME-GC-MS were employed to assess the volatile flavor of post-ripening fermentation. A total of 29 key volatile aroma components played a crucial role in the development of post-ripening flavor in shrimp paste with or without sunlight. Lipidomic analysis revealed that sunlight promoted the oxidative degradation of FA, resulting in the production of a diverse range of flavor compounds that imparted the unique aroma of shrimp paste. The findings of this study will establish a theoretical basic for better control of the post-ripening fermentation of traditional shrimp paste.

3.
Blood ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728428

RESUMO

Complete remission with partial hematological recovery (CRh) has been used as an efficacy endpoint in clinical trials of nonmyelosuppressive drugs for acute myeloid leukemia (AML). We conducted a pooled analysis to characterize the clinical outcomes for patients with AML who achieved CRh after treatment with ivosidenib, olutasidenib, enasidenib, or gilteritinib monotherapy in clinical trials used to support marketing applications. The study cohort included 841 adult patients treated at the recommended drug dosage; 64.6% were red blood cell or platelet transfusion dependent at study baseline. Correlations between disease response and outcomes were assessed by logistic regression modeling for categorical variables and by Cox proportional hazards modeling for time-to-event variables. In comparison to patients with no response (NR), those with CRh had a higher proportion with transfusion independence (TI) for at least 56 days (92.3% vs 22.3%, p < 0.0001) or TI for at least 112 days (63.5% vs 8.7%, p < 0.0001), a reduced risk over time for severe infection (HR 0.43, p = 0.0007) or severe bleeding (HR 0.17, p = 0.01), and a longer overall survival (OS) (HR 0.31, p < 0.0001). The effects were consistent across drugs. In comparison to patients with CR, the effect sizes for CRh were similar for TI-56 and for risk over time of infection or bleeding but less for TI-112 and OS. CRh is associated with clinical benefits consistent with clinically meaningful palliative effects for treatment of AML with nonmyelosuppressive drugs, although less robustly than for CR.

4.
Food Chem ; 452: 139542, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38728898

RESUMO

This study investigated the effects of ethanol, 1,2-propanediol, and glycerol on the structure and aggregation behavior of silver carp (Hypophthalmichthys molitrix) myosin. All alcohols induced extensive alteration in the tertiary structure of myosin. Both ethanol and 1,2-propanediol further promoted an increase in the content of ß-sheets in myosin and induced myosin aggregation. While glycerol had almost no impact on the secondary structure of myosin. Molecular dynamics simulations revealed that increasing the concentration of ethanol and 1,2-propanediol affected the overall structural changes in the myosin heavy chain (MHC), while glycerol exerted a more pronounced effect on the MHC tail when compared to the MHC head. Disruption of the hydration layers induced by ethanol and 1,2-propanediol contributed to local structural changes in myosin. Glycerol at a concentration of 20% induced the formation of a larger hydration layer around the MHC tail, which facilitated the stabilization of the protein structure.

5.
Theor Appl Genet ; 137(6): 126, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727833

RESUMO

KEY MESSAGE: The gene controlling pink flesh in watermelon was finely mapped to a 55.26-kb region on chromosome 6. The prime candidate gene, Cla97C06G122120 (ClPPR5), was identified through forward genetics. Carotenoids offer numerous health benefits; while, they cannot be synthesized by the human body. Watermelon stands out as one of the richest sources of carotenoids. In this study, genetic generations derived from parental lines W15-059 (red flesh) and JQ13-3 (pink flesh) revealed the presence of the recessive gene Clpf responsible for the pink flesh (pf) trait in watermelon. Comparative analysis of pigment components and microstructure indicated that the disparity in flesh color between the parental lines primarily stemmed from variations in lycopene content, as well as differences in chromoplast number and size. Subsequent bulk segregant analysis (BSA-seq) and genetic mapping successfully narrowed down the Clpf locus to a 55.26-kb region on chromosome 6, harboring two candidate genes. Through sequence comparison and gene expression analysis, Cla97C06G122120 (annotated as a pentatricopeptide repeat, PPR) was predicted as the prime candidate gene related to pink flesh trait. To further investigate the role of the PPR gene, its homologous gene in tomato was silenced using a virus-induced system. The resulting silenced fruit lines displayed diminished carotenoid accumulation compared with the wild-type, indicating the potential regulatory function of the PPR gene in pigment accumulation. This study significantly contributes to our understanding of the forward genetics underlying watermelon flesh traits, particularly in relation to carotenoid accumulation. The findings lay essential groundwork for elucidating mechanisms governing pigment synthesis and deposition in watermelon flesh, thereby providing valuable insights for future breeding strategies aimed at enhancing fruit quality and nutritional value.


Assuntos
Mapeamento Cromossômico , Citrullus , Frutas , Fenótipo , Pigmentação , Proteínas de Plantas , Citrullus/genética , Citrullus/metabolismo , Pigmentação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Frutas/genética , Genes de Plantas , Carotenoides/metabolismo , Genes Recessivos , Regulação da Expressão Gênica de Plantas , Cromossomos de Plantas/genética , Licopeno/metabolismo
6.
Front Immunol ; 15: 1390958, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765016

RESUMO

This study presents two cases of type II mixed cryoglobulinemia. One case is essential, while the other is presumably associated with hepatitis B virus (HBV) infection. Both patients tested positive for monoclonal IgMκ, but negative for MyD88 mutation. They showed resistance to rituximab combined with a glucosteroid regimen, but responded positively to BTK inhibitors. These cases highlight the remarkable effectiveness of BTK inhibitors in treating refractory type II cryoglobulinemia without MyD88 mutation. The first patient achieved rapid complete remission of nephrotic syndrome within one month of starting ibrutinib, along with a significant reduction in cryoglobulin levels and abnormal clonal cells. The second patient had a rapid disappearance of rash within three days and accelerated wound healing within one week of initiating orelabrutinib, accompanied by a reduction in C-reactive protein. However, there was no reduction in cryoglobulin levels during the 12-month follow-up. These findings suggest varied mechanisms of action of BTK inhibitors in type II cryoglobulinemia through different mechanisms.


Assuntos
Tirosina Quinase da Agamaglobulinemia , Crioglobulinemia , Fator 88 de Diferenciação Mieloide , Inibidores de Proteínas Quinases , Humanos , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Crioglobulinemia/tratamento farmacológico , Crioglobulinemia/etiologia , Fator 88 de Diferenciação Mieloide/genética , Inibidores de Proteínas Quinases/uso terapêutico , Pessoa de Meia-Idade , Masculino , Feminino , Adenina/análogos & derivados , Adenina/uso terapêutico , Idoso , Piperidinas/uso terapêutico , Resultado do Tratamento
7.
Anal Cell Pathol (Amst) ; 2024: 8972022, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38715918

RESUMO

Preeclampsia (PE) manifests as a pregnancy-specific complication arising from compromised placentation characterized by inadequate trophoblast invasion. A growing body of evidence underscores the pivotal involvement of pseudogenes, a subset of long noncoding RNAs, in the pathological processes of PE. This study presents a novel finding, demonstrating a significant downregulation of the pseudogene PDIA3P1 in PE placental tissues compared to normal tissues. In vitro functional assays revealed that suppressing PDIA3P1 hindered trophoblast proliferation, invasion, and migration, concurrently upregulating the expression of secreted frizzled-related protein 1 (SFRP1). Further exploration of the regulatory role of PDIA3P1 in PE, utilizing human trophoblasts, established that PDIA3P1 exerts its function by binding to HuR, thereby enhancing the stability of Snail expression in trophoblasts. Overall, our findings suggest a crucial role for PDIA3P1 in regulating trophoblast properties and contributing to the pathogenesis of PE, offering potential targets for prognosis and therapeutic intervention.


Assuntos
Regulação para Baixo , Fenótipo , Pré-Eclâmpsia , RNA Longo não Codificante , Fatores de Transcrição da Família Snail , Trofoblastos , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Feminino , Trofoblastos/metabolismo , Trofoblastos/patologia , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/patologia , Gravidez , Regulação para Baixo/genética , Fatores de Transcrição da Família Snail/metabolismo , Fatores de Transcrição da Família Snail/genética , Proliferação de Células/genética , Movimento Celular/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Isomerases de Dissulfetos de Proteínas/genética , Adulto
8.
ACS Nano ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38759100

RESUMO

Nanoagrochemicals present promising solutions for augmenting conventional agriculture, while insufficient utilization of nanobiointerfacial interactions hinders their field application. This work investigates the multiscale physiochemical interactions between nanoagrochemicals and rice (Oryza sativa L.) leaves and devises a strategy for elevating targeting efficiency of nanoagrochemicals and stress resilience of rice. We identified multiple deposition behaviors of nanoagrochemicals on hierarchically structured leaves and demonstrated the crucial role of leaf microarchitectures. A transition from the Cassie-Baxter to the Wenzel state significantly changed the deposition behavior from superlattice assembly, ring-shaped aggregation to uniform monolayer deposition. By fine-tuning the formulation properties, we achieved a 415.9-fold surge in retention efficiency, and enhanced the sustainability of nanoagrochemicals by minimizing loss during long-term application. This biointerface design significantly relieved the growth inhibition of Cd(II) pollutant on rice plants with a 95.2% increase in biomass after foliar application of SiO2 nanoagrochemicals. Our research elucidates the intricate interplay between leaf structural attributes, nanobiointerface design, and biological responses of plants, fostering field application of nanoagrochemicals.

9.
Aesthetic Plast Surg ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38691173

RESUMO

BACKGROUND: In recent years, soft tissue materials have been applied as forehead fillers. Some filling materials need to be removed or refilled in a timely manner in certain situations; therefore, it is important to develop a method to identify the location and type of filling materials. This study summarizes the imaging findings of different filling materials under high-frequency ultrasound, providing a reference for clinical treatment. METHODS: We screened facial ultrasound images performed at the Plastic Surgery Hospital of the Chinese Academy of Medical Sciences from April 2015 to July 2023 and classified and summarized the types of frontal filling materials and their imaging results. RESULTS: This study included ultrasound imaging results from 114 patients, including 39 with hyaluronic acid (HA) filling, 45 with polyacrylamide hydrogel (PAG) filling, 14 who received autologous fat transplantation, 2 who received prosthesis implantation, 2 who received both HA and PAG filling, and 12 who received silicone oil filling. HA mainly manifests as an anechoic zone on ultrasonography, with images divisible into four types. PAG primarily presents as fine punctate echoes, divisible into five types. Fat transplantation presents as a low-echo area with uneven density, divisible into five types. Finally, the silicone oil-filling material appears as a cloud-like high echo on the forehead, visible throughout the entire skin layer, and unclear imaging in deep tissues. CONCLUSION: High-frequency ultrasound is a safe and reliable method to evaluate the type and position of forehead filling materials, which can be easily applied in clinical practice. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

11.
ACS Biomater Sci Eng ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752228

RESUMO

Due to the decomposition temperature of Polyamide 66 (PA66) in the environment is close to its thermoforming temperature, it is difficult to construct porous scaffolds of PA66/nanohydroxyapatite (PA66/HAp) by fused deposition modeling (FDM) three-dimensional (3D) printing. In this study, we demonstrated for the first time a method for 3D printing PA66/HAp composites at room temperature, prepared PA66/HAp printing ink using a mixed solvent of formic acid/dichloromethane (FA/DCM), and constructed a series of composite scaffolds with varying HAp content. This printing system can print composite materials with a high HAp content of 60 wt %, which is close to the mineral content in natural bone. The physicochemical evaluation presented that the hydroxyapatite was uniformly distributed within the PA66 matrix, and the PA66/HAp composite scaffold with 30 wt % HAp content exhibited optimal mechanical properties and printability. The results of in vitro cell culture experiments indicated that the incorporation of HAp into the PA66 matrix significantly improved the cell adhesion, proliferation, and osteogenic differentiation of bone marrow stromal cells (BMSCs) cultured on the scaffold. In vivo animal experiments suggested that the PA66/HAp composite material with 30 wt % HAp content had the best structural maintenance and osteogenic performance. The three-dimensional PA66/HAp composite scaffold prepared by low temperature printing in the current study holds great potential for the repair of large-area bone defects.

12.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557883

RESUMO

Quantitative phase imaging (QPI) provides 3D structural and morphological information for label free living cells. Unfortunately, this quantitative phase information cannot meet doctors' diagnostic requirements of the clinical "gold standard," which displays stained cells' pathological states based on 2D color features. To make QPI results satisfy the clinical "gold standard," the virtual staining method by QPI for label free lymphocytes based on self-supervised iteration Cycle-Consistent Adversarial Networks (CycleGANs) is proposed herein. The 3D phase information of QPI is, therefore, trained and transferred to a kind of 2D "virtual staining" image that is well in agreement with "gold standard" results. To solve the problem that unstained QPI and stained "gold standard" results cannot be obtained for the same label free living cell, the self-supervised iteration for the CycleGAN deep learning algorithm is designed to obtain a trained stained result as the ground truth for error evaluation. The structural similarity index of our virtual staining experimental results for 8756 lymphocytes is 0.86. Lymphocytes' area errors after converting to 2D virtual stained results from 3D phase information are less than 3.59%. The mean error of the nuclear to cytoplasmic ratio is 2.69%, and the color deviation from the "gold standard" is less than 6.67%.


Assuntos
Algoritmos , Imageamento Quantitativo de Fase , Coloração e Rotulagem
13.
J Gastrointest Surg ; 28(4): 365-374, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38583885

RESUMO

BACKGROUND: Adjuvant chemotherapy (CT) constitutes the primary approach for treating resectable advanced gastric cancer (GC). However, the effectiveness of postoperative CT can differ across various patient groups. This retrospective study aimed to examine how variances in clinical and pathologic factors affect postoperative CT. METHODS: This study enrolled 2060 patients with GC who underwent curative gastrectomy at Zhejiang Cancer Hospital between January 2008 and December 2017, with 1277 receiving postoperative CT. This study used Kaplan-Meier to determine the effect of clinical and pathology factors on CT benefits. In addition, univariate and multivariate Cox regression analyses were used to identify independent prognosis risk factors. RESULTS: Both univariate and multivariate analyses demonstrated that the absence of postoperative CT is an independent factor associated with a poor prognosis in patients with GC. The Kaplan-Meier univariate analysis revealed that specific subgroups, including males, those with a normal body mass index (BMI), the elderly, individuals with gastric adenocarcinoma, cases of nerve invasion by the tumor, vascular invasion by the tumor, tumor size ≥ 5 cm, and Tumor, Node, Metastasis (TNM) stage III, exhibited improved treatment outcomes with the administration of postoperative CT. The creation of nomograms using Cox regression and the rms package holds significant clinical relevance. CONCLUSION: Postoperative CT is advantageous for prolonging the survival of advanced patients undergoing D2 gastrectomy, particularly in male patients, the elderly, individuals with a normal BMI score, those diagnosed with gastric adenocarcinoma, cases, in which the tumor invades nerves or blood vessels, patients with a tumor size of ≥5 cm, and those with a TNM stage of III, as it results in improved treatment outcomes within these subgroups.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Humanos , Masculino , Idoso , Estudos Retrospectivos , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Quimioterapia Adjuvante , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Gastrectomia/métodos
14.
Int J Ophthalmol ; 17(4): 736-747, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638264

RESUMO

AIM: To analysis of research hotspots and trends on the application of premium intraocular lens (PIOLs) in the past 2 decades. METHODS: The literature search was performed on the Web of Science and included PIOLs studies published between January 2000 and December 2022. The retrieved literature was collated and analyzed by R-tool's Bibliometrix package, CitNetExplorer, CiteSpace and other software. RESULTS: A total of 1801 articles about PIOLs were obtained, most of which were published in Spain and the United States. The organization that published the most articles was the University of Valencia in Spain. Alió JL, and Montés-Micó R, from Spain were the most influential authors in this field. The Journal of Cataract and Refractive Surgery and Journal of Refractive Surgery were the core journals for this field; the top 10 cited articles mainly focus on postoperative satisfaction with multifocal intraocular lens (IOLs) and postoperative results of toric IOLs. Through the keyword analysis, we found that trifocal IOLs, astigmatism and extended depth of focus (EDoF) IOLs are the most discussed topics at present, and the importance of astigmatism and the clinical application of the new generation of PIOLs are the emerging research trends. CONCLUSION: Bibliometric analysis can effectively help to identify multilevel concerns in PIOLs research and the prevailing research trends in the realm of PIOLs encompass the adoption of EDoF IOLs, trifocal IOLs, and their respective Toric models.

17.
BMJ Open ; 14(4): e080211, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589256

RESUMO

OBJECTIVES: The elimination of mother-to-child transmission (MTCT) of syphilis has been set as a public health priority. However, an instrument to predict the MTCT of syphilis is not available. We aimed to develop and validate an intuitive nomogram to predict the individualised risk of MTCT in pregnant women with syphilis in China. DESIGN: Retrospective cohort study. SETTING: Data was acquired from the National Information System of Prevention of MTCT of Syphilis in Guangdong province between 2011 and 2020. PARTICIPANTS: A total of 13 860 pregnant women with syphilis and their infants were included and randomised 7:3 into the derivation cohort (n=9702) and validation cohort (n=4158). PRIMARY OUTCOME MEASURES: Congenital syphilis. RESULTS: Among 13 860 pregnant women with syphilis and their infants included, 1370 infants were diagnosed with congenital syphilis. Least absolute shrinkage and selection operator regression and multivariable logistic regression showed that age, ethnicity, registered residence, marital status, number of pregnancies, transmission route, the timing of syphilis diagnosis, stage of syphilis, time from first antenatal care to syphilis diagnosis and toluidine red unheated serum test titre were predictors of MTCT of syphilis. A nomogram was developed based on the predictors, which demonstrated good calibration and discrimination with an area under the curve of the receiver operating characteristic of 0.741 (95% CI: 0.728 to 0.755) and 0.731 (95% CI: 0.710 to 0.752) for the derivation and validation cohorts, respectively. The net benefit of the predictive models was positive, demonstrating a significant potential for clinical decision-making. We have also developed a web calculator based on this prediction model. CONCLUSIONS: Our nomogram exhibited good performance in predicting individualised risk for MTCT of syphilis, which may help guide early and personalised prevention for MTCT of syphilis.


Assuntos
Complicações Infecciosas na Gravidez , Sífilis Congênita , Sífilis , Lactente , Gravidez , Feminino , Humanos , Gestantes , Sífilis/diagnóstico , Sífilis/epidemiologia , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Sífilis Congênita/diagnóstico , Sífilis Congênita/prevenção & controle , Nomogramas , Estudos Retrospectivos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle
18.
Microbiol Spectr ; : e0424023, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687059

RESUMO

The interaction between coexisting plasmids can affect plasmid-carried resistance gene persistence and spread. However, whether the persistence of the blaCTX-M gene in clinical Enterobacteriaceae is related to the interaction of coresident nonresistance-conferring plasmids has not been reported. This study was initiated to elucidate how a nonresistance-conferring IncI1 plasmid affected the blaCTX-M-bearing IncFII plasmid colocated on the same cell. Herein, we constructed three isogenic derivatives of E. coli C600, designated as C600FII, C600I1, and C600FII+I1, which harbored the blaCTX-M-IncFII plasmid and/or the nonresistance-IncI1 one. We discovered that strain C600FII+I1 conferred higher fitness advantages than strain C600FII; also, the stability of the blaCTX-M-IncFII plasmid was noticeably improved in an antibiotic-free environment when it coexisted with the IncI1 plasmid. To further explore why the IncI1 plasmid enhanced the persistence of the blaCTX-M-IncFII plasmid, we assessed the blaCTX-M-IncFII plasmid's copy numbers, conjugation frequencies, and rep gene expressions in strains C600FII and C600FII+I1. The results demonstrated that the rep expressions of the blaCTX-M-IncFII plasmid in strain C600FII+I1 was greatly decreased, along with the plasmid's copy numbers and mating efficiencies, compared to those in strain C600FII. Moreover, further study revealed that the intracellular ATP levels of strain C600FII+I1 were far lower than those of strain C600FII. Our findings confirmed that coexistence of the nonresistance-IncI1 plasmid can keep the blaCTX-M-IncFII plasmid more stable by increasing the fitness advantages of the host bacteria, which will pose a threat to preventing the long-term presence of the plasmid-carried blaCTX-M gene in clinical Enterobacteriaceae. IMPORTANCE: So far, plasmid-carried blaCTX-M is still the most common extended-spectrum beta-lactamase (ESBL) genotype in clinical settings worldwide. Except for the widespread use of third-generation cephalosporins, the interaction between coexisting plasmids can also affect the long-term stable existence of the blaCTX-M gene; however, the study on that is still sparse. In the present study, we assess the interaction of coinhabitant plasmids blaCTX-M-IncFII and nonresistance-IncI1. Our results confirmed that the increased fitness advantages of strain C600FII+I1 were attributable to the cohabitant nonresistance-IncI1 plasmid, which largely reduced the intracellular ATP levels of host bacteria, thus decreasing the rep gene expression of the blaCTX-M-IncFII plasmid, its copy numbers, and mating efficiencies, while the higher fitness advantages of strain C600FII+I1 enhanced the persistence of the blaCTX-M-IncFII plasmid. The results indicate that the nonresistance-IncI1 plasmid contributes to the long-term existence of the blaCTX-M-IncFII plasmid, implying a potentially new strategy for controlling the spread of resistance plasmids in clinical settings by targeting nonresistance plasmids.

19.
Mikrochim Acta ; 191(5): 281, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38649632

RESUMO

Two chiral covalent organic frameworks (CCOFs) core-shell microspheres based on achiral organic precursors by chiral-induced synthesis strategy for HPLC enantioseparation are reported for the first time. Using n-hexane/isopropanol as mobile phase, various kinds of racemates were selected as analytes and separated on the CCOF-TpPa-1@SiO2 and CCOF-TpBD@SiO2-packed columns with a low column backpressure (3 ~ 9 bar). The fabricated two CCOFs@SiO2 chiral columns exhibited good separation performance towards various racemates with high column efficiency (e.g., 19,500 plates m-1 for (4-fluorophenyl)ethanol and 18,900 plates m-1 for 1-(4-chlorophenyl)ethanol) and good reproducibility. Some effects have been investigated such as the analyte mass and column temperature on the HPLC enantioseparation. Moreover, the chiral separation results of the CCOF-TpPa-1@SiO2 chiral column and the commercialized Chiralpak AD-H column show a good complementarity. This study demonstrates that the usage of chiral-induced synthesis strategy for preparing CCOFs core-shell microspheres as a novel stationary phase has a good application potential in HPLC.

20.
Soft Matter ; 20(18): 3780-3786, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38639061

RESUMO

Acylphosphatase (AcP) is an enzyme which catalyses the hydrolysis of acylphosphate. The binding with the phosphate ion (Pi) assumes significance in preserving both the stability and enzymatic activity of AcP. While previous studies using single molecule force spectroscopy explored the mechanical properties of AcP, the influence of Pi on its folding and unfolding dynamic behaviors remains unexplored. In this work, using stable magnetic tweezers, we measured and compared the force-dependent folding and unfolding rates of AcP in the Tris buffer and phosphate buffer within a force range from 2 pN to 40 pN. We found that Pi exerts no discernible effect on the folding dynamics but consistently decreases the force-dependent unfolding rate of AcP by a constant ratio across the entire force spectrum. The free energy landscapes of AcP in the absence and presence of Pi are constructed. Our results reveal that Pi selectively binds to the native state of AcP, stabilizing it and suggesting the general properties of specific ligand-receptor interactions.


Assuntos
Acilfosfatase , Dobramento de Proteína , Desdobramento de Proteína , Termodinâmica , Ligantes , Fosfatos/química , Fosfatos/metabolismo
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