Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 122
Filtrar
1.
Small ; 20(23): e2307997, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38148323

RESUMO

Sulfide solid electrolytes (SSEs) are highly wanted for solid-state batteries (SSBs). While their liquid-phase synthesis is advantageous over their solid-phase strategy in scalable production, it confronts other challenges, such as low-purity products, user-unfriendly solvents, energy-inefficient solvent removal, and unsatisfactory performance. This article demonstrates that a suspension-based solvothermal method using single oxygen-free solvents can solve those problems. Experimental observations and theoretical calculations together show that the basic function of suspension-treatment is "interparticle-coupled unification", that is, even individually insoluble solid precursors can mutually adsorb and amalgamate to generate uniform composites in nonpolar solvents. This anti-intuitive concept is established when investigating the origins of impurities in SSEs electrolytes made by the conventional tetrahydrofuran-ethanol method and then searching for new solvents. Its generality is supported by four eligible alkane solvents and four types of SSEs. The electrochemical assessments on the former three SSEs show that they are competitive with their counterparts in the literature. Moreover, the synthesized SSEs presents excellent battery performance, showing great potential for practical applications.

2.
Neuroimage ; 283: 120426, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37898378

RESUMO

The level of consciousness undergoes continuous alterations during anesthesia. Prior to the onset of propofol-induced complete unconsciousness, degraded levels of behavioral responsiveness can be observed. However, a reliable index to monitor altered consciousness levels during anesthesia has not been sufficiently investigated. In this study, we obtained 60-channel EEG data from 24 healthy participants during an ultra-slow propofol infusion protocol starting with an initial concentration of 1 µg/ml and a stepwise increase of 0.2 µg/ml in concentration. Consecutive auditory stimuli were delivered every 5 to 6 s, and the response time to the stimuli was used to assess the responsiveness levels. We calculated the spectral slope in a time-resolved manner by extracting 5-second EEG segments at each auditory stimulus and estimated their correlation with the corresponding response time. Our results demonstrated that during slow propofol infusion, the response time to external stimuli increased, while the EEG spectral slope, fitted at 15-45 Hz, became steeper, and a significant negative correlation was observed between them. Moreover, the spectral slope further steepened at deeper anesthetic levels and became flatter during anesthesia recovery. We verified these findings using an external dataset. Additionally, we found that the spectral slope of frontal electrodes over the prefrontal lobe had the best performance in predicting the response time. Overall, this study used a time-resolved analysis to suggest that the EEG spectral slope could reliably track continuously altered consciousness levels during propofol anesthesia. Furthermore, the frontal spectral slope may be a promising index for clinical monitoring of anesthesia depth.


Assuntos
Anestesia , Propofol , Humanos , Propofol/farmacologia , Estado de Consciência/fisiologia , Eletroencefalografia , Inconsciência/induzido quimicamente , Anestésicos Intravenosos/farmacologia
3.
Oral Dis ; 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37338083

RESUMO

OBJECTIVES: The objectives of the study was to discuss the effect and mechanism of fluctuant glucose (FG) on implant osseointegration in type 2 diabetic mellitus (T2DM). MATERIALS AND METHODS: Rats were divided into control, T2DM and FG group, and the implants were inserted into their femurs. Micro-CT and histological analysis were used to evaluate the effect on osseointegration in vivo. And we investigated the effect of different conditions (normal, control, high glucose, and FG medium) on rat osteoblast in vitro. Then transmission electron microscope (TEM) and Western blot were used to evaluate the endoplasmic reticulum stress (ERS) response. Finally, 4-PBA, an inhibitor of ERS, was added into different conditions to observe the functions of osteoblast. RESULTS: In vivo, Micro-CT and histological analysis showed that the percentage of osseointegration in FG rats were lower than other two group. In vitro, the results demonstrated that the adhesion of the cells becomes worst, and osteogenic ability was also severely impaired in FG group. In addition, FG could induce more serious ERS and 4-PBA could improve the dysfunction of osteoblasts induced by FG. CONCLUSION: Fluctuant glucose could restrain the implant osseointegration in T2DM, and the effect was more obvious than consistent high glucose by a possible mechanism of activation ERS pathway.

4.
BMC Musculoskelet Disord ; 24(1): 166, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879207

RESUMO

BACKGROUND: Thoracolumbar fascia injury (FI) is rarely discussed in osteoporotic vertebral fracture (OVF) patients in previous literature and it is usually neglected and treated as an unmeaning phenomenon. We aimed to evaluate the characteristics of the thoracolumbar fascia injury and further discuss its clinical significance in the treatment of kyphoplasty for osteoporotic vertebral fracture (OVF) patients. METHODS: Based on the presence or absence of FI, 223 OVF patients were divided into two groups. The demographics of patients with and without FI were compared. The visual analogue scale and Oswestry disability index scores were compared preoperatively and after PKP treatment between these groups. RESULTS: Thoracolumbar fascia injuries were observed in 27.8% of patients. Most FI showed a multi-level distribution pattern which involved a mean of 3.3 levels. Location of fractures, severity of fractures and severity of trauma were significantly different between patients with and without FI. In further comparison, severity of trauma was significantly different between patients with severe and non-severe FI. In patients with FI, VAS and ODI scores of 3 days and 1 month after PKP treatment were significantly worse compared to those without FI. It showed the same trend in VAS and ODI scores in patients with severe FI when compared to those patients with non-severe FI. CONCLUSIONS: FI is not rare in OVF patients and presents multiple levels of involvement. The more serious trauma suffered, the more severe thoracolumbar fascia injury presented. The presence of FI which was related to residual acute back pain significantly affected the effectiveness of PKP in treating OVFs. TRIAL REGISTRATION: retrospectively registered.


Assuntos
Cifoplastia , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Fáscia
5.
BMC Oral Health ; 22(1): 650, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36578061

RESUMO

BACKGROUND: Osteogenesis of lateral window sinus elevation surgery is the key to placement of the subsequent implant, excessive collapse of the sub-antral space may adversely affect long-term stability of implants. At present, few studies focus on the influence of the contact area of the sub-antral space on osteogenesis. This study evaluated whether the change in the contact area of the sub-antral space with maxillary sinus bone and the Schneiderian membrane can affect osteogenesis. METHODS: Cone beam computed tomography (CBCT) images were collected of patients requiring maxillary sinus floor elevation (residual bone height < 6 mm) for standard-length implant placement before surgery, after surgery, and at 6-month follow-up visits. The postoperative sub-antral space volume (V1) and surface area (S1), and the remaining volume after six months of healing (V2) were measured. Then, the contact area of sub-antral space with maxillary sinus bone (Sbc) and the Schneiderian membrane (Smc), the absorbed volume during healing (Va), and the percentage of remaining volume (V2%) and absorbed volume (Va%) were calculated. The correlation between anatomical parameters was analyzed using multiple linear regression. RESULTS: A total of 62 maxillary sinuses from 56 patients were augmented, of which 57 were considered for the final analysis (5 withdrew due to perforation). Multiple linear regression results demonstrated that Sbc was significantly positively correlated with Va (ß coefficient = 0.141, p < 0.01) without correlation between Smc and Va (ß coefficient = - 0.046, p = 0.470). There was a positive correlation between Sbc and V2% (ß coefficient = 2.269, p < 0.05). CONCLUSIONS: This study confirmed that the size of the Sbc in lateral window sinus elevation surgery affected osteogenesis after six months of healing. Clinicians should assess the sinus contour type preoperatively, then consider whether it is necessary to expand the range of the Schneiderian membrane elevation to avoid excessive collapse of the sub-antral space. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR), ChiCTR2200057924. Registered 22 March 2022-Retrospectively registered.


Assuntos
Osteogênese , Levantamento do Assoalho do Seio Maxilar , Humanos , Levantamento do Assoalho do Seio Maxilar/métodos , Estudos Prospectivos , Mucosa Nasal , Implantação Dentária Endóssea/métodos , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia
6.
J Pharmacol Exp Ther ; 379(2): 134-146, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34413198

RESUMO

Conjugation of small interfering RNA (siRNA) to tris N-acetylgalactosamine [(GalNAc)3] can enable highly selective, potent, and durable knockdown of targeted proteins in the liver. However, potential knowledge gaps between in vitro experiments, preclinical species, and clinical scenarios remain. A minimal physiologically based pharmacokinetic-pharmacodynamic model for GalNAc-conjugated siRNA (GalNAc-siRNA) was developed using published data for fitusiran (ALN-AT3), an investigational compound targeting liver antithrombin (AT), to delineate putative determinants governing the whole-body-to-cellular pharmacokinetic (PK) and pharmacodynamic (PD) properties of GalNAc-siRNA and facilitate preclinical-to-clinical translation. The model mathematically linked relevant mechanisms: 1) hepatic biodistribution, 2) tris-GalNAc binding to asialoglycoprotein receptors (ASGPRs) on hepatocytes, 3) ASGPR endocytosis and recycling, 4) endosomal transport and escape of siRNA, 5) cytoplasmic RNA-induced silencing complex (RISC) loading, 6) degradation of target mRNA by bound RISC, and 7) knockdown of protein. Physiologic values for 36 out of 48 model parameters were obtained from the literature. Kinetic parameters governing (GalNAc)3-ASGPR binding and internalization were derived from published studies of uptake in hepatocytes. The proposed model well characterized reported pharmacokinetics, RISC dynamics, and knockdown of AT mRNA and protein by ALN-AT3 in mice. The model bridged multiple PK-PD data sets in preclinical species (mice, rat, monkey) and successfully captured reported plasma pharmacokinetics and AT knockdown in a phase I ascending-dose study. Estimates of in vivo potency were similar (∼2-fold) across species. Subcutaneous absorption and serum AT degradation rate constants scaled across species by body weight with allometric exponents of -0.29 and -0.22. The proposed mechanistic modeling framework characterizes the unique PK-PD properties of GalNAc-siRNA. SIGNIFICANCE STATEMENT: Tris N-acetylgalactosamine (GalNAc)3-conjugated small interfering RNA (siRNA) therapeutics enable liver-targeted gene therapy and precision medicine. Using a translational and systems-based minimal physiologically based pharmacokinetic-pharmacodynamic (mPBPK-PD) modeling approach, putative determinants influencing GalNAc-conjugated siRNA (GalNAc-siRNA) functionality in three preclinical species and humans were investigated. The developed model successfully integrated and characterized relevant published in vitro-derived biomeasures, mechanistic PK-PD profiles in animals, and observed clinical PK-PD responses for an investigational GalNAc-siRNA (fitusiran). This modeling effort delineates the disposition and liver-targeted pharmacodynamics of GalNAc-siRNA.


Assuntos
Acetilgalactosamina/farmacocinética , Inativação Gênica/fisiologia , Modelos Biológicos , RNA Interferente Pequeno/farmacocinética , Acetilgalactosamina/genética , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Haplorrinos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Camundongos , RNA Interferente Pequeno/genética , Ratos , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
7.
Langmuir ; 37(47): 13941-13951, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34780183

RESUMO

High-voltage spinel materials have attracted widespread attention because of their advantages such as good rate performance, low cost, abundant source, and easy preparation. However, the Mn dissolution and Jahn-Teller effect of spinel materials during cycling limit their practical application. In this paper, the allogenic composites (1 - x)Li(Ni0.2Co0.1Mn0.7)2 O4·xLi1.2(Ni0.2Co0.1Mn0.7)0.8O2 (x = 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5) are developed by the carbonate co-precipitation method combined with the high-temperature sintering method, which are certified by the X-ray diffraction (XRD) spectrum and transmission electron microscopy (TEM) image. The results show that the lithium-rich phase of the allogenic composites can effectively improve the initial discharge capacity, alleviate the side reaction between the spinel material and the electrolyte, and improve the cycle stability. This work reveals the relationship between the structure and electrochemical performance of the in situ transformed spinel@Li-rich allogenic composites and provide a new clue to design a high-performance spinel cathode for advanced Li-ion batteries.

8.
Langmuir ; 37(13): 4016-4024, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33761744

RESUMO

The lithium-sulfur (Li-S) battery is an ideal electrochemical energy storage system owing to the high theoretical energy density and acceptable cost of finance and the environment. However, some disadvantages, including low electrical conductivity, poor sulfur utilization, and rapid capacity fading, obstruct its practical application. In this work, 3D carbon foam from a melamine resin is synthesized via high-temperature calcination. Carbon nanotubes (CNTs) and MnO2 are utilized to tailor the properties of the 3D cathode collector in the liquid Li2S6-containing Li-S battery without additional conductive agents, binders, and aluminum foil. Herein, the decorated MnO2 on the carbon fiber foam prolongs the lifespan of the Li-S battery, and adding CNTs is beneficial to enhance the capacity and cyclic performance of the Li-S battery under high sulfur loading. The Li-S battery with a sulfur loading of 3 mg cm-2 possesses a reversible capacity of 437.9 mA h g-1 after 400 cycles at 0.1 C. The capacity could be maintained at 568 mA h g-1 at 0.1 C after 80 cycles when the sulfur loading increases to 6 mg cm-2.

9.
Biopharm Drug Dispos ; 42(5): 191-203, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33638217

RESUMO

The pharmacokinetic (PK) parameters of dexamethasone (DEX) in 11 species were collected from the literature and clearances (CL) assessed by basic allometric methods, and concentration-time course profiles were fitted using two PK models incorporating physiological or allometric scaling. Plots of log CL vs. log body weights (BW) correlated reasonably with R2  = 0.91, with a maximum ratio of actual to fitted CL of 6 (for pig). A minimal physiologically-based pharmacokinetic (mPBPK) model containing blood and two lumped tissue compartments and integrated utilization of physiological parameters was compared to an allometric two-compartment model (a2CM). The plasma PK profiles of DEX from 11 species were analyzed jointly, with the mPBPK model having conserved partition coefficients (Kp ), physiologic blood and tissue volumes, and species-specific CL values. The DEX PK profiles were reasonably captured by the mPBPK model for 9 of 11 species in the joint analysis with three fitted parameters (besides CL) including an overall tissue-to-plasma partition coefficient of 1.07. The a2CM with distribution CL and central and peripheral volumes scaled allometrically fitted the plasma concentration profiles similarly but required a total of six parameters (besides CL). Overall, the literature reported that DEX CL values exhibit moderate variability (mean = 0.64 L/h/kg; coefficient of variation = 105%), but distribution parameters were largely conserved across most species.


Assuntos
Anti-Inflamatórios/farmacocinética , Dexametasona/farmacocinética , Glucocorticoides/farmacocinética , Modelos Biológicos , Animais , Anti-Inflamatórios/sangue , Dexametasona/sangue , Glucocorticoides/sangue , Humanos , Especificidade da Espécie
10.
Drug Metab Dispos ; 48(9): 811-818, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32601175

RESUMO

Blood and multitissue concentration-time profiles for dexamethasone (DEX), a synthetic corticosteroid, were measured in male rats after subcutaneous bolus and infusion dosing. A physiologically based pharmacokinetics (PBPK) model was applied for 12 measured tissues. Tissue partition coefficients (K p ) and metabolic clearance were assessed from infusion studies. Blood cell to plasma partitioning (0.664) and plasma free fraction (0.175) for DEX were found to be moderate. DEX was extensively partitioned into liver (K p = 6.76), whereas the calculated K p values of most tissues ranged between 0.1 and 1.5. Despite the moderate lipophilicity of DEX (log P = 1.8), adipose exhibited very limited distribution (K p = 0.17). Presumably due to P-glycoprotein-mediated efflux, DEX concentrations were very low in brain compared with its expected high permeability. Infusion studies yielded K p values from male and female rats at steady state that were similar. In silico K p values calculated for different tissues by using GastroPlus software were similar to in vivo values except for adipose and liver. Glucocorticoid receptors are found in diverse tissues, and these PBPK modeling results may help provide exposure profiles driving pharmacodynamic effects of DEX. SIGNIFICANCE STATEMENT: Our physiologically based pharmacokinetics model describes the experimentally determined tissue and plasma dexamethasone (DEX) pharmacokinetics (PK) profiles in rats reasonably well. This model can serve for further investigation of DEX tissue distribution in rats as the PK driving force for PD effects in different tissues. No major sex differences were found for DEX tissue distribution. Knowledge gained in this study may be translatable to higher-order species including humans.


Assuntos
Dexametasona/farmacocinética , Glucocorticoides/farmacocinética , Modelos Biológicos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Simulação por Computador , Dexametasona/administração & dosagem , Avaliação Pré-Clínica de Medicamentos , Feminino , Glucocorticoides/administração & dosagem , Infusões Subcutâneas , Masculino , Modelos Animais , Ratos , Fatores Sexuais , Distribuição Tecidual
11.
J Biomech Eng ; 142(8)2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32320015

RESUMO

Cell-generated tractions play an important role in various physiological and pathological processes such as stem-cell differentiation, cell migration, wound healing, and cancer metastasis. Traction force microscopy (TFM) is a technique for quantifying cellular tractions during cell-matrix interactions. Most applications of this technique have heretofore assumed that the matrix surrounding the cells is linear elastic and undergoes infinitesimal strains, but recent experiments have shown that the traction-induced strains can be large (e.g., more than 50%). In this paper, we propose a novel three-dimensional (3D) TFM approach that consistently accounts for both the geometric nonlinearity introduced by large strains in the matrix, and the material nonlinearity due to strain-stiffening of the matrix. In particular, we pose the TFM problem as a nonlinear inverse hyperelasticity problem in the stressed configuration of the matrix, with the objective of determining the cellular tractions that are consistent with the measured displacement field in the matrix. We formulate the inverse problem as a constrained minimization problem and develop an efficient adjoint-based minimization procedure to solve it. We first validate our approach using simulated data, and quantify its sensitivity to noise. We then employ the new approach to recover tractions exerted by NIH 3T3 cells fully encapsulated in hydrogel matrices of varying stiffness. We find that neglecting nonlinear effects can induce significant errors in traction reconstructions. We also find that cellular tractions roughly increase with gel stiffness, while the strain energy appears to saturate.


Assuntos
Microscopia de Força Atômica , Tração , Animais , Movimento Celular , Hidrogéis , Camundongos
12.
J Cell Mol Med ; 23(10): 6690-6699, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31373168

RESUMO

Tyrosine-protein phosphatase non-receptor type 2 (PTPN2) is an important protection factor for diabetes and periodontitis, but the underlying mechanism remains elusive. This study aimed to identify the substrate of PTPN2 in mediating beneficial effects of 25-Hydroxyvitamin D3 (25(OH)2D3 ) on diabetic periodontitis. 25(OH)2D3 photo-affinity probe was synthesized with the minimalist linker and its efficacy to inhibit alveolar bone loss, and inflammation was evaluated in diabetic periodontitis mice. The probe was used to pull down the lysates of primary gingival fibroblasts. We identified PTPN2 as a direct target of 25(OH)2D3 , which effectively inhibited inflammation and bone resorption in diabetic periodontitis mice. In addition, we found that colony-stimulating factor 1 receptor (CSF1R) rather than JAK/STAT was the substrate of PTPN2 to regulate bone resorption. PTPN2 direct interacted with CSF1R and dephosphorylated Tyr807 residue. In conclusion, PTPN2 dephosphorylates CSF1R at Y807 site and inhibits alveolar bone resorption in diabetic periodontitis mice. PTPN2 and CSF1R are potential targets for the therapy of diabetic periodontitis or other bone loss-related diseases.


Assuntos
Perda do Osso Alveolar/enzimologia , Calcifediol/uso terapêutico , Diabetes Mellitus Experimental/complicações , Periodontite/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/microbiologia , Perda do Osso Alveolar/fisiopatologia , Animais , Calcifediol/química , Células Cultivadas , Citocinas/metabolismo , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Gengiva/citologia , Gengiva/enzimologia , Gengiva/metabolismo , Gengiva/patologia , Inflamação/genética , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Periodontite/tratamento farmacológico , Periodontite/metabolismo , Periodontite/microbiologia , Porphyromonas gingivalis , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , RNA Interferente Pequeno , Tirosina/metabolismo
13.
Biochem Biophys Res Commun ; 519(2): 351-357, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31514995

RESUMO

Phenyllactate (PLA) is found in a variety of fermented foods and is a promising antibacterial agent, drug and plastic synthetic precursor. Previous studies have shown that PLA is a product of Phe catabolism in lactic acid bacteria (LAB), and PLA biosynthesis is mainly related to lactate dehydrogenases (LDHs). Here, the genome, transcriptome and fermentation characteristics of PLA-producing Lactobacillus plantarum LY-78 were studied. The fermentation experiments demonstrated that L. plantarum LY-78 possesses the ability to synthesize PLA de novo. Secondly, the genome and transcriptome analyses revealed candidate pathways, operons and key genes for PLA biosynthesis in the strain. Finally, genome-wide transcriptome analysis revealed significant changes in the expression profile of strain LY-78 in the absence and presence of PPA. Overall, this work demonstrates for the first time that PLA can be a by-product of Phe anabolism in LAB, provides new insights and evidence for elucidating the mechanism of PLA biosynthesis in LAB, and may provide new candidate genes and research strategies for future PLA biosynthesis applications.


Assuntos
Fermentação , Lactatos/metabolismo , Lactobacillales/química , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Lactatos/química , Lactobacillales/metabolismo , Estrutura Molecular , Transcriptoma
14.
J Pharmacol Exp Ther ; 370(2): 318-326, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31197020

RESUMO

The plasma and tissue binding properties of two corticosteroids, dexamethasone (DEX) and methylprednisolone (MPL), were assessed in the rat in anticipation of developing physiologically based pharmacokinetic and pharmacokinetic/pharmacodynamic models. The tissue-to-plasma partition coefficients (K P) of DEX and MPL were measured in liver, muscle, and lung in vivo after steady-state infusion and bolus injection in rats. Since K P is often governed by reversible binding to macromolecules in blood and tissue, an attempt was made to assess K P values of DEX and MPL by in vitro binding studies using rat tissue homogenates and to compare these estimates to those obtained from in vivo kinetics after dosing. The K P values of both steroids were also calculated in rat tissues using mechanistic tissue composition-based equations. The plasma binding of DEX and MPL was linear with moderate binding (60.5% and 82.5%) in male and female rats. In vivo estimates of steroid uptake appeared linear across the tested concentrations and K P was highest in liver and lowest in muscle for both steroids. Assessment of hepatic binding of MPL in vitro was severely affected by drug loss at 37°C in male liver homogenates, whereas DEX was stable in both male and female liver homogenates. With the exception of MPL in liver, in vitro-derived K P estimates reasonably agreed with in vivo values. The mechanistic equations modestly underpredicted K P for both drugs. Tissue metabolism, saturable tissue binding, and active uptake are possible factors that can complicate assessments of in vivo tissue binding of steroids when using tissue homogenates. SIGNIFICANCE STATEMENT: Assuming the free hormone hypothesis, the ratio of the unbound drug fraction in plasma and in tissues defines the tissue-to-plasma partition coefficient (K P), an important parameter in physiologically based pharmacokinetic modeling that determines total drug concentrations within tissues and the steady-state volume of distribution. This study assessed the plasma and tissue binding properties of the synthetic corticosteroids, dexamethasone and methylprednisolone, in rats using ultrafiltration and tissue homogenate techniques. In vitro-in vivo and in silico-in vivo extrapolation of K P was assessed for both drugs in liver, muscle, and lung. Although the extrapolation was fairly successful across the tissues, in vitro homogenate studies severely underpredicted the K P of methylprednisolone in liver, partly attributable to the extensive hepatic metabolism.


Assuntos
Dexametasona/farmacologia , Dexametasona/farmacocinética , Metilprednisolona/farmacologia , Metilprednisolona/farmacocinética , Modelos Biológicos , Animais , Proteínas Sanguíneas/metabolismo , Simulação por Computador , Dexametasona/metabolismo , Estabilidade de Medicamentos , Feminino , Masculino , Metilprednisolona/metabolismo , Ratos , Ratos Wistar , Distribuição Tecidual
15.
Microb Pathog ; 127: 1-6, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30458254

RESUMO

Burkholderia sp. JP2-270, a bacterium with a strong ability to inhibit the growth of Rhizoctonia solani, was isolated from the rhizosphere of rice. The phylogenetic analysis based on 16S rRNA gene revealed that JP2-270 belonged to Burkholderia cepacia complex. Here, we present the complete genome sequence of Burkholderia sp. JP2-270, which consists of three circular chromosomes (Chr1 3,723,585 bp, Chr2 3,274,969 bp, Chr3 1,483,367 bp) and two plasmids (Plas1 15,126 bp, Plas2 428,263 bp). A total of 8193 protein coding genes were predicted in the genome, including 67 tRNA genes, 18 rRNA genes and 4 ncRNA genes. In addition, mutation analysis of Burkholderia sp. JP2-270 revealed that the gene bysR (DM992_17470), encoding a lysR-type transcriptional regulator, was essential for the antagonistic activity of Burkholderia sp. JP2-270 against R. solani GD118 in vitro and in vivo. Identification of regulatory gene associated with antagonistic activity will contribute to understand the antagonistic mechanism of Burkholderia sp. JP2-270.


Assuntos
Antibiose , Antifúngicos/metabolismo , Burkholderia/genética , Burkholderia/metabolismo , Genoma Bacteriano , Rhizoctonia/crescimento & desenvolvimento , Análise de Sequência de DNA , Proteínas de Bactérias/genética , Burkholderia/classificação , Burkholderia/isolamento & purificação , Cromossomos Bacterianos , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fases de Leitura Aberta , Oryza , Filogenia , Plasmídeos , RNA Ribossômico 16S/genética , Rizosfera , Microbiologia do Solo
16.
Fish Shellfish Immunol ; 87: 871-878, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30776542

RESUMO

Viral infection is often accompanied with alteration of intracellular redox state, especially an imbalance between reactive oxygen species (ROS) production and antioxidant cellular defenses. The previous studies showed that an antioxidant cellular defense system, the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), played an important role against spring viraemia of carp virus (SVCV) infection in fish. To further reveal the mediated mechanism that Nrf2 active state was affected by protein kinase C (PKC), here we evaluated SVCV replication in host cells by treated with a strong activator of PKC phorbol-12-myristate-13-acetate (PMA) and an inhibitor staurosporine. Our results showed that PMA significantly repressed SVCV replication and viral-induced apoptosis in Epithelioma papulosum cyprini (EPC) cell, suggesting that PKC may exhibit an anti-SVCV effect. Likewise, PMA resulted in a higher phosphorylation levels of PKCε rather than PKCα/ß to participate in the activation of Nrf2, mainly involved in the activation of Nrf2 phosphorylation of Ser40 to favor Nrf2 translocation to nucleus. Furthermore, the data revealed that PMA up-regulated an antiviral response heme oxygenase-1 (HO1) gene expression that was confirmed as the key player against SVCV infection by HO1 specific siRNA. Overall, this study provided a new therapeutic target for the treatment of SVCV infection, and modulating PKC activity could be used for the prevention and treatment of SVCV.


Assuntos
Carpas/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Fator 2 Relacionado a NF-E2/imunologia , Proteína Quinase C-épsilon/imunologia , Rhabdoviridae/fisiologia , Acetato de Tetradecanoilforbol/análogos & derivados , Animais , Antioxidantes/metabolismo , Carpas/genética , Linhagem Celular , Proteínas de Peixes/genética , Fator 2 Relacionado a NF-E2/genética , Proteína Quinase C-épsilon/genética , Espécies Reativas de Oxigênio/metabolismo , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária , Acetato de Tetradecanoilforbol/farmacologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-32831420

RESUMO

Tractions exerted by cells on their surroundings play an important role in many biological processes including stem cell differentiation, tumorigenesis, cell migration, cancer metastasis, and angiogenesis. The ability to quantify these tractions is important in understanding and manipulating these processes. Three-dimensional traction force microscopy (3DTFM) provides reliable means of evaluating cellular tractions by first measuring the displacement of fluorescent beads in response to these tractions in the surrounding matrix, and then using this measurement to compute the tractions. However, most applications of 3DTFM assume that the surrounding extra-cellular matrix (ECM) is non-fibrous, despite the fact that in many natural and synthetic environments the ECM contains a significant proportion of fibrous components. Motivated by this, we develop a computational approach for determining tractions, while accounting for the fibrous nature of the ECM. In particular, we make use of a fiber-based constitutive model in which the stress contains contributions from a distribution of nonlinear elastic fibers and a hyperelastic matrix. We solve an inverse problem with the nodal values of the traction vector as unknowns, and minimize the difference between a predicted displacement field, obtained by solving the equations of equilibrium in conjunction with the fiber-based constitutive model, and the measured displacement field at the bead locations. We employ a gradient-based minimization method to solve this problem and determine the gradient efficiently by solving for the appropriate adjoint field. We apply this algorithm to problems with experimentally observed cell geometries and synthetic, albeit realistic, traction fields to gauge its sensitivity to noise, and quantify the impact of using an incorrect constitutive model: the so-called model error. We conclude that the approach is robust to noise, yielding about 10% error in tractions for 5% displacement noise. We also conclude that the impact of model error is significant, where using a nonlinear exponential hyperelastic model instead of the fiber-based model, can lead to more than 100% error in the traction field. These results underline the importance of using appropriate constitutive models in 3DTFM, especially in fibrous ECM constructs.

18.
Pharm Res ; 35(11): 203, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30191329

RESUMO

PURPOSE: Collagen-induced arthritic (CIA) rats are used commonly for preclinical pharmacologic research into rheumatoid arthritis (RA). Dexamethasone (DEX), a potent corticosteroid (CS), remains an important component in combination therapy for RA. Although sex differences in RA and CS pharmacokinetics/pharmacodynamics (PK/PD) have been documented in humans, there has been no such comprehensive evaluation of sex differences in CIA rats. METHODS: Paw size measurements were obtained for males and females from four groups of animals: healthy controls, non-drug treated arthritic animals, and both 0.225 and 2.25 mg/kg DEX-treated arthritic animals. A turnover model for disease progression, minimal PBPK model for drug concentrations, and inhibitory indirect response model were applied using population PK/PD modeling. RESULTS: The clearances of DEX were 43% greater in males, but other PK parameters were similar. The temporal profiles of paw swelling exhibited earlier progression, peak edema times, and disease remission in females. DEX suppressed paw edema well in both males and females with similar capacity (Imax) values (=1.0), but DEX potency was less in females with higher IC50 values (0.101 versus 0.015 ng/mL). CONCLUSIONS: The pharmacology of DEX was well characterized in CIA rats. This study addresses knowledge gaps about sex differences and can be a guide for more mechanistic assessment of sex, drug, and disease differences in RA.


Assuntos
Antirreumáticos/farmacologia , Artrite Experimental/tratamento farmacológico , Dexametasona/farmacologia , Animais , Antirreumáticos/uso terapêutico , Artrite Experimental/induzido quimicamente , Artrite Experimental/fisiopatologia , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/fisiopatologia , Colágeno , Dexametasona/uso terapêutico , Progressão da Doença , Feminino , Masculino , Ratos , Ratos Endogâmicos Lew , Fatores Sexuais
19.
Fish Shellfish Immunol ; 76: 93-100, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29427720

RESUMO

Vibrio alginolyticus, a bacterial pathogen in fish and humans, expresses a type III secretion system (T3SS) that is critical for pathogen virulence and disease development. However, little is known about the associated effectors (T3SEs) and their physiological role. In this study, the T3SE gene hopPmaJ (hop) was cloned from V. alginolyticus wild-type strain HY9901 and the mutant strain HY9901Δhop was constructed by the in-frame deletion method. The results showed that the deduced amino acid sequence of V. alginolyticus HopPmaJ shared 78-98% homology with other Vibrio spp. In addition, the HY9901Δhop mutant showed an attenuated swarming phenotype and a 2600-fold decrease in the virulence to grouper. However, the HY9901Δhop mutant showed no difference in morphology, growth, biofilm formation and ECPase activity. Finally, grouper vaccinated via intraperitoneal (IP) injection with HY9901Δhop induced a high antibody titer with a relative percent survival (RPS) value of 84% after challenging with the wild-type HY9901. Real-time PCR assays showed that vaccination with HY9901Δhop enhanced the expression of immune-related genes, including MHC-Iα, MHC-IIα, IgM, and IL-1ß after vaccination, indicating that it is able to induce humoral and cell-mediated immune response in grouper. These results demonstrate that the HY9901Δhop mutant could be used as an effective live vaccine to combat V. alginolyticus in grouper.


Assuntos
Vacinas Bacterianas/imunologia , Bass , Doenças dos Peixes/prevenção & controle , Vacinas Atenuadas/imunologia , Vibrioses/veterinária , Vibrio alginolyticus/fisiologia , Sequência de Aminoácidos , Animais , Mutação , Distribuição Aleatória , Homologia de Sequência , Vibrioses/prevenção & controle , Vibrio alginolyticus/genética , Vibrio alginolyticus/patogenicidade , Virulência
20.
Acta Radiol ; 59(11): 1351-1357, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29482346

RESUMO

Background Kyphoplasty has been demonstrated to be minimally invasive and effective in treating osteoporotic vertebral fracture patients with back pain over the level of the fractured vertebrae. Rare studies have reported on thoracolumbar vertebral fracture patients presenting with distal lumbosacral pain (DLP). Whether kyphoplasty had a favorable therapeutic benefit for these patients remains unclear. Purpose To evaluate the therapeutic efficacy of kyphoplasty in treating osteoporotic thoracolumbar vertebral fracture (OTVF) patients with DLP and assess the clinical significance of focal tenderness to palpation in these patients. Material and Methods Thirty-two OTVF patients who only complained of DLP were treated by kyphoplasty. The vertebral heights, local kyphotic angle, Visual Analogue Scale (VAS), and Oswestry Disability Index (ODI) scores were assessed preoperatively, one day after surgery, and at last follow-up. All patients were evaluated regarding their degree of satisfaction with kyphoplasty. In addition, we compared the therapeutic efficacy of kyphoplasty in patients with and without focal tenderness to palpation. Results All patients successfully underwent kyphoplasty without complications. The vertebral heights, local kyphotic angles, VAS, and ODI scores were all significantly improved after kyphoplasty and maintained at last follow-up in our patients ( P < 0.001). At last follow-up, all patients expressed satisfaction with kyphoplasty. No significant differences in these parameters were detected between patients with and without focal tenderness. Conclusion The possibility of thoracolumbar vertebral fractures in elderly patients complaining of DLP should not be neglected. Kyphoplasty presents a superior benefit in treating OTVF patients with DLP. The absence of focal tenderness does not influence the clinical efficacy in these patients.


Assuntos
Fraturas por Compressão/terapia , Cifoplastia/métodos , Dor Lombar/terapia , Fraturas por Osteoporose/complicações , Fraturas por Osteoporose/terapia , Fraturas da Coluna Vertebral/terapia , Idoso , Feminino , Fraturas por Compressão/complicações , Fraturas por Compressão/diagnóstico por imagem , Humanos , Dor Lombar/etiologia , Dor Lombar/fisiopatologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Região Lombossacral/diagnóstico por imagem , Masculino , Fraturas por Osteoporose/diagnóstico por imagem , Estudos Retrospectivos , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/fisiopatologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA