RESUMEN
Multi-resistant Staphylococcus aureus (S. aureus) infection is a significant global health concern owing to its high mortality and morbidity rates. Coagulase (Coa), a key enzyme that activates prothrombin to initiate host coagulation, has emerged as a promising target for anti-infective therapeutic approaches. This study identified sinigrin as a potent Coa inhibitor that significantly inhibited S. aureus-induced coagulation at concentration as low as 32 mg/L. Additionally, at a higher concentration of 128 mg/L, sinigrin disrupted the self-protection mechanism of S. aureus. Thermal shift and fluorescence-quenching assays confirmed the direct binding of sinigrin to the Coa protein. Molecular docking analysis predicted specific binding sites for sinigrin in the Coa molecule, and point mutation experiments highlighted the importance of Arg-187 and Asp-222 as critical binding sites for both Coa and sinigrin. In vivo studies demonstrated that the combination of sinigrin with oxacillin exhibited greater antibacterial efficacy than oxacillin alone in the treatment of S. aureus-induced pneumonia in mice. Furthermore, sinigrin was shown to reduce bacterial counts and inflammatory cytokine levels in the lung tissues of S. aureus-infected mice. In summary, sinigrin was shown to directly target Coa, resulting in the attenuation of S. aureus virulence, which suggests the potential of sinigrin as an adjuvant for future antimicrobial therapies.
Asunto(s)
Antibacterianos , Coagulasa , Simulación del Acoplamiento Molecular , Infecciones Estafilocócicas , Staphylococcus aureus , Coagulasa/metabolismo , Animales , Ratones , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/patogenicidad , Staphylococcus aureus/enzimología , Virulencia/efectos de los fármacos , Antibacterianos/farmacología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Modelos Animales de Enfermedad , Citocinas/metabolismo , Oxacilina/farmacología , Sitios de Unión , Coagulación Sanguínea/efectos de los fármacos , Pulmón/microbiología , Pulmón/patología , Femenino , Ratones Endogámicos BALB CRESUMEN
BACKGROUND: In recent years, the prevalence of respiratory fungal diseases has increased. Polyene antifungal drugs play a pivotal role in the treatment of these conditions, with amphotericin B (AmB) being the most representative drug. This study aimed to evaluate the efficacy and safety of topical administration of AmB in the treatment of respiratory fungal infections. METHODS: We conducted a retrospective study on hospitalized patients treated with topical administered AmB for respiratory fungal infections from January 2014 to June 2023. RESULTS: Data from 36 patients with invasive pulmonary fungal infections treated with topical administration of AmB were collected and analyzed. Nebulization was administered to 27 patients. After the treatment, 17 patients evidenced improved conditions, whereas 10 patients did not respond and died in the hospital. One patient experienced an irritating cough as an adverse reaction. Seven patients underwent tracheoscopic instillation, and two received intrapleural irrigation; they achieved good clinical therapeutic efficacy without adverse effects. CONCLUSION: The combined application of systemic antifungal treatment and topical administration of AmB yielded good therapeutic efficacy and was well-tolerated by the patients. Close monitoring of routine blood tests, liver and kidney function, and levels of electrolytes, troponin, and B-type natriuretic peptide supported this conclusion.
Asunto(s)
Administración Tópica , Anfotericina B , Antifúngicos , Humanos , Anfotericina B/administración & dosificación , Anfotericina B/uso terapéutico , Anfotericina B/efectos adversos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Antifúngicos/administración & dosificación , Antifúngicos/uso terapéutico , Antifúngicos/efectos adversos , Anciano , Adulto , Resultado del Tratamiento , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/microbiología , Anciano de 80 o más Años , Enfermedades Pulmonares Fúngicas/tratamiento farmacológico , Adulto JovenRESUMEN
The catalytic versatility of pentacoordinated iron is highlighted by the broad range of natural and engineered activities of heme enzymes such as cytochrome P450s, which position a porphyrin cofactor coordinating a central iron atom below an open substrate binding pocket. This catalytic prowess has inspired efforts to design de novo helical bundle scaffolds that bind porphyrin cofactors. However, such designs lack the large open substrate binding pocket of P450s, and hence, the range of chemical transformations accessible is limited. Here, with the goal of combining the advantages of the P450 catalytic site geometry with the almost unlimited customizability of de novo protein design, we design a high-affinity heme-binding protein, dnHEM1, with an axial histidine ligand, a vacant coordination site for generating reactive intermediates, and a tunable distal pocket for substrate binding. A 1.6 Å X-ray crystal structure of dnHEM1 reveals excellent agreement to the design model with key features programmed as intended. The incorporation of distal pocket substitutions converted dnHEM1 into a proficient peroxidase with a stable neutral ferryl intermediate. In parallel, dnHEM1 was redesigned to generate enantiocomplementary carbene transferases for styrene cyclopropanation (up to 93% isolated yield, 5000 turnovers, 97:3 e.r.) by reconfiguring the distal pocket to accommodate calculated transition state models. Our approach now enables the custom design of enzymes containing cofactors adjacent to binding pockets with an almost unlimited variety of shapes and functionalities.
Asunto(s)
Hemo , Porfirinas , Hemo/química , Metales , Sistema Enzimático del Citocromo P-450/metabolismo , Hierro/química , Porfirinas/química , Sitios de UniónRESUMEN
Oxygenase and peroxygenase enzymes generate intermediates at their active sites which bring about the controlled functionalization of inert C-H bonds in substrates, such as in the enzymatic conversion of methane to methanol. To be viable catalysts, however, these enzymes must also prevent oxidative damage to essential active site residues, which can occur during both coupled and uncoupled turnover. Herein, we use a combination of stopped-flow spectroscopy, targeted mutagenesis, TD-DFT calculations, high-energy resolution fluorescence detection X-ray absorption spectroscopy, and electron paramagnetic resonance spectroscopy to study two transient intermediates that together form a protective pathway built into the active sites of copper-dependent lytic polysaccharide monooxygenases (LPMOs). First, a transient high-valent species is generated at the copper histidine brace active site following treatment of the LPMO with either hydrogen peroxide or peroxyacids in the absence of substrate. This intermediate, which we propose to be a CuII-(histidyl radical), then reacts with a nearby tyrosine residue in an intersystem-crossing reaction to give a ferromagnetically coupled (S = 1) CuII-tyrosyl radical pair, thereby restoring the histidine brace active site to its resting state and allowing it to re-enter the catalytic cycle through reduction. This process gives the enzyme the capacity to minimize damage to the active site histidine residues "on the fly" to increase the total turnover number prior to enzyme deactivation, highlighting how oxidative enzymes are evolved to protect themselves from deleterious side reactions during uncoupled turnover.
Asunto(s)
Cobre , Histidina , Oxigenasas de Función Mixta , Estrés Oxidativo , CatálisisRESUMEN
The development of bio-based polymer materials, such as polylactic acid (PLA) -based polymers, is an effective strategy to reduce dependence on petrochemical-based polymers. However, the preparation of bio-based polymers with high barrier properties is a major challenge. To overcome this challenge, a nacreous layer structure with a ' brick and mud ' pattern is mimicked to improve the overall performance of the material. In this paper, Poly (L -lactic acid) (PLLA) and Polypropylene Glycol (PPG) was combined to prepare bio-based polyurethane (PU-PLLA), which is used as the slurry structure of nacreous layer. The bio-based biomimetic composite membrane (PU-PLLA/BN) is then obtained by adding boron nitride (BN, brick structure of pearl layer) to it. The water vapor permeability test results show that the permeability of PU-PLLA material can be reduced by more than 50% by 5 wt.% BN, which is because the addition of BN can increase the length and tortuosity of the gas molecular diffusion path in the composite. Therefore, this pearl-inspired PU-PLLA/BN film has excellent moisture resistance, which opens up a broad road for the practical application of PLLA in flexible laminated packaging.
Asunto(s)
Poliésteres , Polímeros , Poliésteres/química , Polímeros/química , Embalaje de Productos , PermeabilidadRESUMEN
The biotin-streptavidin technology has been extensively exploited to engineer artificial metalloenzymes (ArMs) that catalyze a dozen different reactions. Despite its versatility, the homotetrameric nature of streptavidin (Sav) and the noncooperative binding of biotinylated cofactors impose two limitations on the genetic optimization of ArMs: (i) point mutations are reflected in all four subunits of Sav, and (ii) the noncooperative binding of biotinylated cofactors to Sav may lead to an erosion in the catalytic performance, depending on the cofactor:biotin-binding site ratio. To address these challenges, we report on our efforts to engineer a (monovalent) single-chain dimeric streptavidin (scdSav) as scaffold for Sav-based ArMs. The versatility of scdSav as host protein is highlighted for the asymmetric transfer hydrogenation of prochiral imines using [Cp*Ir(biot-p-L)Cl] as cofactor. By capitalizing on a more precise genetic fine-tuning of the biotin-binding vestibule, unrivaled levels of activity and selectivity were achieved for the reduction of challenging prochiral imines. Comparison of the saturation kinetic data and X-ray structures of [Cp*Ir(biot-p-L)Cl]·scdSav with a structurally related [Cp*Ir(biot-p-L)Cl]·monovalent scdSav highlights the advantages of the presence of a single biotinylated cofactor precisely localized within the biotin-binding vestibule of the monovalent scdSav. The practicality of scdSav-based ArMs was illustrated for the reduction of the salsolidine precursor (500 mM) to afford (R)-salsolidine in 90% ee and >17â¯000 TONs. Monovalent scdSav thus provides a versatile scaffold to evolve more efficient ArMs for in vivo catalysis and large-scale applications.
Asunto(s)
Biotina/química , Ingeniería Química/métodos , Metaloproteínas/química , Compuestos Organometálicos/química , Estreptavidina/química , Sitios de Unión , Biotina/genética , Biotinilación , Catálisis , Cromatografía de Afinidad , Escherichia coli/genética , Hidrogenación , Iridio/química , Cinética , Metaloproteínas/genética , Estereoisomerismo , Estreptavidina/genéticaRESUMEN
OBJECTIVES: This study was aimed to develop small molecule inhibitors of the P. aeruginosa heme oxygenase (pa-HemO) as potential treatment of infections caused by P. aeruginosa. METHODS: New compounds were designed based on the crystal structure of pa-HemO. The binding affinities (KD) were determined using intrinsic fluorescence quenching assays. The anti-microbial effects of the new compounds was evaluated by minimal inhibitory concentration 50% (MIC50). RESULTS: Eleven compounds were synthesized as potential pa-HemO inhibitors. New compounds demonstrated KD values ranging from 1.5 to 180⯵M, and MIC50 values ranging from 26 to 260⯵g/mL. The compounds had good affinity with HemO and promising anti-microbial effects on P. aeruginosa. CONCLUSIONS: The new inhibitors described herein can inhibit the growth of P. aeruginosa via the inhibition of pa-HemO. There may be broad prospects for HemO inhibitors to treat P. aeruginosa related infections.
Asunto(s)
Antibacterianos/farmacología , Inhibidores Enzimáticos/farmacología , Hemo Oxigenasa (Desciclizante)/antagonistas & inhibidores , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Antibacterianos/síntesis química , Antibacterianos/metabolismo , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/metabolismo , Hemo Oxigenasa (Desciclizante)/química , Hemo Oxigenasa (Desciclizante)/metabolismo , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Unión Proteica , Conformación Proteica , Pseudomonas aeruginosa/enzimologíaRESUMEN
Paternally expressed gene-10 (PEG10) could participate in several carcinomas and might be regulated by miR-491. To now, miR-491 was found to play an important role in the sensitivity and mechanism of drug usage in the treatment of colorectal cancer, and drug resistance is a key factor to affect the disease healing. In this study, miR-491, PEG10, Wnt1, and ß-catenin expression levels and their correlation with colorectal cancer were assessed in cancer tissues and adjacent parts. And the target relationship between PEG10 and miR-491 was verified. Meanwhile, the impaction of Curcumin on miR-491, PEG10, and Wnt/ß-catenin signaling pathway were analyzed in HCT-116 cells. The effects of PEG10 and Curcumin on human HCT-116 cells proliferation and apoptosis were investigated by MTT and flow cytometry assay. Results showed that the expression of miR-491 in colon cancer tissues was decreased, but PEG10, Wnt1, and ß-catenin were higher than that in adjacent tissues. The PEG10 gene 3' UTR could combine with miR-491 seed sequence and miR-491 overexpression could cause a decrease in PEG10, Wnt1, and ß-catenin levels in human HCT-116 cells. Furthermore, PEG10 overexpression increased the expression levels of Wnt1 and ß-catenin, thereby promoting cell proliferation and inhibiting apoptosis. In addition, Curcumin could up-regulate miR-491, inhibit PEG10, and Wnt/ß-catenin signaling pathway. Consequently, Curcumin reduced HCT-116 cells proliferation and promoted cells apoptosis via the miR-491/PEG10 pathway. In conclusion, PEG10 was a target gene of miR-491, miR-491/PEG10 strengthen the sensitivity of Curcumin in HCT-116 cells proliferation and apoptosis, which might act as an ideal diagnostic biomarker treatment methods.
Asunto(s)
Antineoplásicos/farmacología , Neoplasias Colorrectales/genética , Curcumina/farmacología , MicroARNs/genética , Proteínas/genética , Anciano , Proteínas Reguladoras de la Apoptosis , Biomarcadores de Tumor/genética , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Proteínas de Unión al ADN , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Unión al ARN , Vía de Señalización Wnt/efectos de los fármacosRESUMEN
Artificial metalloenzymes (ArMs), which combine an abiotic metal cofactor with a protein scaffold, catalyze various synthetically useful transformations. To complement the natural enzymes' repertoire, effective optimization protocols to improve ArM's performance are required. Here we report on our efforts to optimize the activity of an artificial transfer hydrogenase (ATHase) using Escherichia coli whole cells. For this purpose, we rely on a self-immolative quinolinium substrate which, upon reduction, releases fluorescent umbelliferone, thus allowing efficient screening. Introduction of a loop in the immediate proximity of the Ir-cofactor afforded an ArM with up to 5-fold increase in transfer hydrogenation activity compared to the wild-type ATHase using purified mutants.
Asunto(s)
Hidrogenasas/química , Metaloproteínas/química , Ingeniería de Proteínas/métodos , Compuestos de Quinolinio/química , Umbeliferonas/química , Secuencia de Aminoácidos , Secuencia de Bases , Evolución Molecular Dirigida/métodos , Escherichia coli/metabolismo , Hidrogenasas/genética , Hidrogenación , Metaloproteínas/genética , Oxidación-Reducción , Periplasma/metabolismo , Compuestos de Quinolinio/síntesis química , Umbeliferonas/síntesis químicaRESUMEN
PURPOSE: The co-colonization prevalence of P. aeruginosa and A. fumigatus in cystic fibrosis (CF) has been inconsistently reported. The purpose of this systematic review and meta-analysis was to estimate the overall co-colonization prevalence of P. aeruginosa and A. fumigatus in CF. METHODS: The Embase, PubMed and Web of Science databases were systematically searched for studies reporting the co-colonization prevalence of P. aeruginosa and A. fumigatus in CF. The co-colonization prevalence of two pathogenic microorganisms in the individual studies was assessed by calculating the proportion and 95% confidence interval (CI). The random effects model was used to calculate the pooled prevalence. The I2 test was used to assess statistical heterogeneity. The funnel plot and two statistical methods were used to assess publication bias. RESULTS: Twenty-three eligible studies were included in this analysis. The pooled co-colonization prevalence of P. aeruginosa and A. fumigatus in CF patients was 15.8% (95% CI: 9.9-21.8). The co-colonization prevalence of P. aeruginosa and A. fumigatus chronic colonization was lower than that of intermittent colonization, higher in sputum cultures than in bronchoalveolar lavage (BAL) cultures, and lower in children than in adults. There was a statistically significant difference in co-colonization prevalence among studies from different decades, but the prevalence was similar in different geographical regions and with different study types. CONCLUSIONS: The co-colonization prevalence of P. aeruginosa and A. fumigatus in the lower respiratory tract of CF patients was high. The anti-infective treatment in exacerbation of CF should be considered to cover the two pathogenic microorganisms simultaneously. Large-scale research is still needed to obtain more accurate co-colonization data.
Asunto(s)
Aspergillus fumigatus/aislamiento & purificación , Coinfección/epidemiología , Fibrosis Quística/complicaciones , Infecciones por Pseudomonas/epidemiología , Pseudomonas aeruginosa/aislamiento & purificación , Aspergilosis Pulmonar/epidemiología , Coinfección/microbiología , Humanos , Prevalencia , Infecciones por Pseudomonas/microbiología , Aspergilosis Pulmonar/microbiologíaRESUMEN
Background & objectives: Pseudomonas aeruginosa is an opportunistic pathogen that can cause nosocomial bloodstream infections in humans. This study was aimed to explore the association of furanone C-30 with biofilm formation, quorum sensing (QS) system and antibiotic resistance in P. aeruginosa. Methods: An in vitro model of P. aeruginosa bacterial biofilm was established using the standard P. aeruginosa strain (PAO-1). After treatment with 2.5 and 5 µg/ml of furanone C-30, the change of biofilm morphology of PAO-1 was observed, and the expression levels of QS-regulated virulence genes (lasB, rhlA and phzA2), QS receptor genes (lasR, rhlR and pqsR) as well as QS signal molecule synthase genes (lasI, rhlI, pqsE and pqsH) were determined. Besides, the AmpC expression was quantified in planktonic and mature biofilm induced by antibiotics. Results: Furanone C-30 treatment significantly inhibited biofilm formation in a dose-dependent manner. With the increase of furanone C-30 concentration, the expression levels of lasB, rhlA, phzA2, pqsR, lasI, rhlI pqsE and pqsH significantly decreased in mature biofilm bacteria while the expression levels of lasR and rhlR markedly increased. The AmpC expression was significantly decreased in both planktonic and biofilm bacteria induced by imipenem and ceftazidime. Interpretation & conclusions: Furanone C-30 may inhibit biofilm formation and antibiotic resistance in P. aeruginosa through regulating QS genes. The inhibitory effect of furanone C-30 on las system appeared to be stronger than that on rhl system. Further studies need to be done with different strains of P. aeruginosa to confirm our findings.
Asunto(s)
Biopelículas , Farmacorresistencia Microbiana , Furanos/farmacología , Pseudomonas aeruginosa/patogenicidad , Proteínas Bacterianas , Humanos , Percepción de QuorumRESUMEN
1. Curculigoside possesses numerous pharmacological activities, and however, little data available for the effects of curculigoside on the activity of human liver cytochrome P450 (CYP) enzymes. 2. This study investigates the inhibitory effects of curculigoside on the main human liver CYP isoforms. In this study, the inhibitory effects of curculigoside on the eight human liver CYP isoforms 1A2, 2A6, 2E1, 2D6, 2C9, 2C19, 2C8, and 3A4 were investigated in human liver microsomes. 3. The results indicated that curculigoside could inhibit the activity of CYP1A2, CYP2C8, and CYP3A4, with IC50 values of 15.26, 11.93, and 9.47 µM, respectively, but that other CYP isoforms were not affected. Enzyme kinetic studies showed that curculigoside was not only a noncompetitive inhibitor of CYP1A2, but also a competitive inhibitor of CYP2C8 and CYP3A4, with Ki values of 5.43, 3.54, and 3.35 µM, respectively. In addition, curculigoside is a time-dependent inhibitor for CYP1A2, with kinact/KI values of 0.056/6.15 µM-1 min-1. 4. The in vitro studies of curculigoside with CYP isoforms suggest that curculigoside has the potential to cause pharmacokinetic drug interactions with other coadministered drugs metabolized by CYP1A2, CYP2C8, and CYP3A4. Further in vivo studies are needed in order to evaluate the significance of this interaction.
Asunto(s)
Benzoatos/farmacología , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Glucósidos/farmacología , Interacciones Farmacológicas , Humanos , Hígado/metabolismoRESUMEN
Porcelain-fused-to-metal crown is one of the widely-used prostheses among the dental porcelain restorations. Nonprecious metals like NiCr and CoCr have extensively been used for metal-ceramic restorations due to advantages such as inexpensive price, hardness, durability, resistance to deformation, thin thickness of metal of porcelain area, and other mechanical and physical properties. However, the immediate advantage of the CoCr alloy is comparable performance to other base metal alloys, but without an allergenic nickel component. To achieve clinical longevity of porcelain-fused-to-metal (PFM) crowns, it is essential to have adequate bond strength between the metal substrate and porcelain. Any type of metal-ceramic fracture failure can become a costly and timeconsuming problem, both in the clinic and laboratory. Therefore, the suitability of the CoCr alloy for dental applications is critically associated with its ceramic bonding capacity. In this study, CoCr metal alloys modified by acid-etching and sandblasting, oxide layer was formed for subsequent bonding to porcelain ceramics. By both acid-etching and sandblasting oxide layer was formed and showed higher bonding strength at a proper condition, but debonding was occurred at porcelain layer so that they showed highest bonding strength by combined these two kind of surface treatment. Because the oxide film was formed more densely in a vacuum at the portions where more sophisticated concavo-convex were formed on the surface of a metal.
Asunto(s)
Aleaciones de Cromo/química , Aleaciones Dentales/química , Recubrimiento Dental Adhesivo , Porcelana Dental/química , Ensayo de Materiales , Níquel/química , Óxidos/químicaRESUMEN
Titanium as one kind of biomaterials comes in direct contact with the body, making evaluation of biocompatibility an important aspect to biomaterials development. Surface chemistry of titanium plays an important role in osseointegration. Different surface modification alters the surface chemistry and result in different biological response. In this study, three kinds of mixed acid solutions were used to treat Ti specimens to induce Ca-P formation. Following a strong mixed acid activation process, Ca-P coating successfully formed on the Ti surfaces in simulated body fluid. Strong mixed acid increased the roughness of the metal surface, because the porous and rough surface allows better adhesion between Ca-P coatings and substrates. After modification of titanium surface by mixed acidic solution and subsequently H2O2/HCL treatment evaluation of biocompatibility was conducted from hydroxyapatite formation by biomimetic process and cell viability on modified titanium surface. Nano-scale modification of titanium surfaces can alter cellular and tissue responses, which may benefit osseointegration and dental implant therapy. Results from this study indicated that surface treatment methods affect the surface morphology, type of TiO2 layer formed and subsequent apatite deposition and biological responses. The thermo scientific alamarblue cell viability assay reagent is used to quantitatively measure the viability of mammalian cell lines, bacteria and fungi by incorporating a rapid, sensitive and reliable fluorometric/colorimetric growth indicator, without any toxic and side effect to cell line. In addition, mixed acid treatment uses a lower temperature and shorter time period than widely used alkali treatment.
Asunto(s)
Aleaciones/química , Apatitas/metabolismo , Osteoblastos/metabolismo , Titanio/química , Línea Celular , Humanos , Osteoblastos/citología , Propiedades de SuperficieRESUMEN
CONTEXT: Clarifying the potential mechanism of the poor oral bioavailability of curculigoside would be helpful for for investigating pharmacological effects and clinical applications. OBJECTIVE: To clarify the main mechanism for poor oral bioavailability. MATERIALS AND METHODS: First, the pharmacokinetics of curculigoside (20 mg/kg) in rats with and without pretreatment with verapamil (10 mg/kg) was determined using a sensitive and reliable LC-MS method. Then the effects of verapamil on the transport and metabolic stability of curculigoside were investigated using Caco-2 cell transwell model and rat liver microsome incubation systems. RESULTS: The results showed that verapamil could significantly increase the peak plasma concentration (from 60.17 ng/mL to 93.66 ng/mL) and AUC0-t (from 289.57 to 764.02 ng·h/mL) of curculigoside. The Caco-2 cell experiments indicated that the efflux ratio of curculigoside was 3.92 (PappAB 6.43 ± 0.57 × 10 -7 cm/s; PappBA 2.52 ± 0.37 × 10 -36 cm/s), P-gp might be involved in the transport of curculigoside, and verapamil could inhibit the efflux of curculigoside and increase the absorption of curculigoside significantly in the Caco-2 cell monolayer. Additionally, the rat liver microsome incubation experiments indicated that verapamil could significantly decrease the intrinsic clearance rate of curculigoside (from 38.8 to 23.6 µL/min/mg protein). DISCUSSION AND CONCLUSION: These results indicated that verapamil could significantly change the pharmacokinetic profiles of curculigoside in rats, the poor absorption due to P-gp mediated efflux in intestine and high intrinsic clearance rate in rat liver may be the main reason for the poor oral absolute bioavailability of curculigoside.
Asunto(s)
Benzoatos/farmacocinética , Glucósidos/farmacocinética , Verapamilo/farmacocinética , Administración Oral , Animales , Benzoatos/administración & dosificación , Células CACO-2 , Cromatografía Liquida/métodos , Interacciones Farmacológicas/fisiología , Glucósidos/administración & dosificación , Humanos , Masculino , Espectrometría de Masas/métodos , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Ratas , Ratas Sprague-Dawley , Verapamilo/administración & dosificaciónRESUMEN
An efficient method for the enantioselective construction of ß-substituted ß-vinylglycinol derivatives through palladium-catalyzed decarboxylative cycloaddition of vinylethylene carbonates with isocyanates was developed. By using a palladium complex generated in situ from [Pd2 (dba)3]â CHCl3 (dba=dibenzylideneacetone) and (S)-Segphos as a catalyst under mild reaction conditions, the process provided 4-substituted-4-vinyloxazolidin-2-ones in high yields with a high level of enantioselectivity. The stereochemical outcome of the reaction was explained by DFT calculations and the synthetic utility of the process was demonstrated by the gram-scale transformation and formal synthesis of MK-0731 as a kinesin spindle protein inhibitor.
RESUMEN
An artificial metathesase results from incorporation of an Hoveyda-Grubbs catalyst bearing an arylsulfonamide anchor within human carbonic anhydrase II. The optimization of the catalytic performance is achieved upon combining both chemical and genetic means. Up to 28 TONs were obtained within four hours under aerobic physiological conditions.
Asunto(s)
Materiales Biocompatibles/química , Anhidrasa Carbónica II/química , Anhidrasa Carbónica II/metabolismo , Sulfonamidas/química , Materiales Biocompatibles/metabolismo , Catálisis , Humanos , Cinética , Simulación del Acoplamiento Molecular , Conformación Proteica , Relación Estructura-Actividad , Sulfonamidas/metabolismoRESUMEN
The aim of this study was to evaluate the effects of quorum sensing (QS) systems in Pseudomonas aeruginosa (P. aeruginosa) on the expression of ampC gene induced by antibiotics. An in vitro dynamic model of P. aeruginosa biofilms was established in a silicon tube in once-flowthrough system at 37 °C. Biofilm generation was identified by argentation. Biofilm morphology of standard P. aeruginosa strain (PAO-1) and QS systems deficient strains (PDO100, rhlI deficient strain; PAO-JP1, lasI deficient strain; and PAO-MW1, rhlI and lasI deficient strain) were observed by optical microscope. The expression of ampC in PAO1, PAO1 with QS inhibitor (furanone C-30) and the QS deficient strains before and after induced by antibiotics were quantified by real-time quantitative PCR. The biofilms of PAO-1 and PDO100 were much thicker and denser than that of PAO-JP1 and PAO-MW1. Being induced by antibiotics, the expression of ampC in PAO1 and PDO100 was significantly higher than that in PAO-MW1 and PAO-JP1. With the effect of furanone C-30, the expression of ampC in PAO1 induced by antibiotics was reduced in a dose-dependent manner. QS system, especially the las system, plays an important role in both biofilm formation and antimicrobials induced ampC expression and furanone C-30 is a potent inhibitor for P. aeruginosa QS system.
Asunto(s)
Antibacterianos/metabolismo , Proteínas Bacterianas/biosíntesis , Biopelículas/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/fisiología , Percepción de Quorum , beta-Lactamasas/biosíntesis , beta-Lactamas/metabolismo , Técnicas Bacteriológicas , Biopelículas/crecimiento & desarrollo , Ceftazidima/metabolismo , Eliminación de Gen , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Imipenem/metabolismo , Microscopía , Pseudomonas aeruginosa/enzimología , Reacción en Cadena en Tiempo Real de la Polimerasa , TemperaturaRESUMEN
A 27-year-old female visited our hospital with a history of asthma, peripheral blood eosinophilia, increased total IgE, Aspergillus fumigatus specific IgE, reversible mild bronchiectasis, sinusitis, bronchial mucus plugs and cultivation of Aspergillus from BALF. Glucocorticoids therapy is effective. These results met the diagnostic criteria for both allergic bronchopulmonary aspergillosis (ABPM) and eosinophilic granulomatosis with polyangiitis (EGPA). Special attention should be paid to the possibility of both diseases coexisting in the disease process.
RESUMEN
Objective: Despite extensive research on the relationship between pulmonary tuberculosis (PTB) and inflammatory factors, more robust causal evidence has yet to emerge. Therefore, this study aims to screen for inflammatory proteins that may contribute to the susceptibility to PTB in different populations and to explain the diversity of inflammatory and immune mechanisms of PTB in different ethnicity. Methods: The inverse variance weighted (IVW) model of a two-sample Mendelian Randomization (MR) study was employed to conduct causal analysis on data from a genome-wide association study (GWAS). This cohort consisting PTB GWAS datasets from two European and two East Asian populations, as well as 91 human inflammatory proteins collected from 14,824 participants. Colocalization analysis aimed to determine whether the input inflammatory protein and PTB shared the same causal single nucleotide polymorphisms (SNPs) variation within the fixed region, thereby enhancing the robustness of the MR Analysis. Meta-analyses were utilized to evaluate the combined causal effects among different datasets. Results: In this study, we observed a significant negative correlation between tumor necrosis factor-beta levels (The alternative we employ is Lymphotoxin-alpha, commonly referred to as LT) (P < 0.05) and tumor necrosis factor receptor superfamily member 9 levels (TNFRSF9) (P < 0.05). These two inflammatory proteins were crucial protective factors against PTB. Additionally, there was a significant positive correlation found between interleukin-20 receptor subunit alpha levels (IL20Ra) (P < 0.05), which may elevate the risk of PTB. Colocalization analysis revealed that there was no overlap in the causal variation between LT and PTB SNPs. A meta-analysis further confirmed the significant combined effect of LT, TNFRSF9, and IL20Ra in East Asian populations (P < 0.05). Conclusions: Levels of specific inflammatory proteins may play a crucial role in triggering an immune response to PTB. Altered levels of LT and TNFRSF9 have the potential to serve as predictive markers for PTB development, necessitating further clinical validation in real-world settings to ascertain the impact of these inflammatory proteins on PTB.