RESUMEN

BACKGROUND: Polyvinyl alcohol (PVA) is one of the most widely used water-soluble polymers with remarkable mechanical properties. However, water-soluble polymers are among the major organic pollutants of streams, river, and marine ecosystems. Once dispersed in aqueous systems, they can directly interfere with the life cycle of aquatic organisms via direct toxic effects. There is thus an urgent need for microorganisms or enzymes that can efficiently degrade them. Oxidized PVA hydrolase plays an important role in the pathway of PVA biodegradation. It is the key enzyme in the second step of the pathway for complete degradation of PVA. METHODS AND RESULTS: The s-oph gene was cloned from the laboratory-isolated strain Sphingopyxis sp. M19. This gene was expressed in the Escherichia coli system pET32a/s-oph expression vector, with the products forming an inclusion body. By binding with a molecular chaperone, pET32a/s-oph/BL21 (DE3)/pGro7 was successfully constructed, which enabled the s-oph gene to be solubly expressed in E. coli. The protein encoded by the s-oph gene was purified at a yield of 16.8 mg L-1, and its catalytic activity reached 852.71 U mg-1. In the s-oph enzyme reaction system, the efficiency of PVA degradation was increased to 233.5% compared with that of controls. CONCLUSIONS: The s-oph enzyme exhibited the characteristics of being able to degrade PVA with high efficiency, specificity, and stability. This enzyme has good potential for practical application in ameliorating plastic pollution and protecting the environment.

Asunto(s)

Arildialquilfosfatasa , Alcohol Polivinílico , Ecosistema , Escherichia coli/genética , Polímeros

RESUMEN

Active research of metal-containing compounds and enzymes as effective antifungal agents is currently being conducted due to the growing antifungal resistance problem. Metals are attracting special attention due to the wide variety of ligands that can be used for them, including chemically synthesized and naturally obtained variants as a result of the so-called "green synthesis". The main mechanism of the antifungal action of metals is the triggering of the generation and accumulation of reactive oxygen species (ROS). Further action of ROS on various biomolecules is nonspecific. Various hydrolytic enzymes (glucanases and proteases), in turn, exhibit antifungal properties by affecting the structural elements of fungal cells (cell walls, membranes), fungal quorum sensing molecules, fungal own protective agents (mycotoxins and antibiotics), and proteins responsible for the adhesion and formation of stable, highly concentrated populations in the form of biofilms. A wide substrate range of enzymes allows the use of various mechanisms of their antifungal actions. In this review, we discuss the prospects of combining two different types of antifungal agents (metals and enzymes) against mycelial fungi and yeast cells. Special attention is paid to the possible influence of metals on the activity of the enzymes and the possible effects of proteins on the antifungal activity of metal-containing compounds.

Asunto(s)

Antifúngicos , Percepción de Quorum , Antifúngicos/química , Especies Reactivas de Oxígeno/metabolismo , Biopelículas , Antibacterianos/farmacología

RESUMEN

Caspases and poly (ADP-ribose) polymerase 1 (PARP1) have been shown to promote influenza A virus (IAV) replication. However, the relative importance and molecular mechanisms of specific caspases and their downstream substrate PARP1 in regulating viral replication in airway epithelial cells (AECs) remains incompletely elucidated. Here, we targeted caspase 2, 3, 6, and PARP1 using specific inhibitors to compare their role in promoting IAV replication. Inhibition of each of these proteins caused significant decline in viral titer, although PARP1 inhibitor led to the most robust reduction of viral replication. We previously showed that the pro-apoptotic protein Bcl-2 interacting killer (Bik) promotes IAV replication in the AECs by activating caspase 3. In this study, we found that as compared with AECs from wild-type mice, bik-deficiency alone resulted in ~ 3 logs reduction in virus titer in the absence of treatment with the pan-caspase inhibitor (Q-VD-Oph). Inhibiting overall caspase activity using Q-VD-Oph caused additional decline in viral titer by ~ 1 log in bik-/- AECs. Similarly, mice treated with Q-VD-Oph were protected from IAV-induced lung inflammation and lethality. Inhibiting caspase activity diminished nucleo-cytoplasmic transport of viral nucleoprotein (NP) and cleavage of viral hemagglutinin and NP in human AECs. These findings suggest that caspases and PARP1 play major roles to independently promote IAV replication and that additional mechanism(s) independent of caspases and PARP1 may be involved in Bik-mediated IAV replication. Further, peptides or inhibitors that target and block multiple caspases or PARP1 may be effective treatment targets for influenza infection.

Asunto(s)

Virus de la Influenza A , Gripe Humana , Animales , Ratones , Humanos , Virus de la Influenza A/fisiología , Caspasas/metabolismo , Células Epiteliales , Proteínas Reguladoras de la Apoptosis , Nucleoproteínas/metabolismo , Replicación Viral/fisiología , Proteínas Mitocondriales

RESUMEN

The bifunctional enzyme acylpeptide hydrolase (APEH) is involved in important metabolic processes both as an exopeptidase and as an endopeptidase. Hence, the growing interest in the study of this protein and the need to set up in vitro assays for its characterization. This chapter describes two in vitro assays able to detect the activities of APEH, one for the exopeptidase activity and one for the endopeptidase activity. In particular, these assays have been set up on the two APEH isoforms from Antarctic fish, characterized by a distinct functionality and marked exo- and endopeptidase activities.

Asunto(s)

Peces , Péptido Hidrolasas , Animales , Regiones Antárticas , Endopeptidasas/metabolismo , Exopeptidasas/metabolismo , Peces/metabolismo , Péptido Hidrolasas/metabolismo , Proteolisis

RESUMEN

Non-apoptotic caspase-3 activation is critically involved in dendritic spine loss and synaptic dysfunction in Alzheimer's disease. It is, however, not known whether caspase-3 plays similar roles in other pathologies. Using a mouse model of clinically manifest Parkinson's disease, we provide the first evidence that caspase-3 is transiently activated in the striatum shortly after the degeneration of nigrostriatal dopaminergic projections. This caspase-3 activation concurs with a rapid loss of dendritic spines and deficits in synaptic long-term depression (LTD) in striatal projection neurons forming the indirect pathway. Interestingly, systemic treatment with a caspase inhibitor prevents both the spine pruning and the deficit of indirect pathway LTD without interfering with the ongoing dopaminergic degeneration. Taken together, our data identify transient and non-apoptotic caspase activation as a critical event in the early plastic changes of indirect pathway neurons following dopamine denervation.

Asunto(s)

Cuerpo Estriado , Neostriado , Caspasa 3/metabolismo , Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Neostriado/metabolismo , Neuronas/metabolismo

RESUMEN

Recent advancements in surgical training methods have escalated the need for simulators. The EyeSi simulation has played a major role in Ophthalmology training by providing opportunity to the novice residents to grasp the surgical steps of the procedure and master the skill by repeated attempts. Participants were assessed on single level of cataract module and their consecutive scores were assessed with each attempt. It was found that repetitive practice on simulator can help develop proficiency in the desired steps that can ultimately prepare the surgical trainees for real life surgery.

Asunto(s)

Internado y Residencia , Oftalmología , Competencia Clínica , Simulación por Computador , Educación de Postgrado en Medicina/métodos , Humanos , Oftalmología/educación

RESUMEN

Intoxication by organophosphorus (OP) poisons, like nerve agents and pesticides, is characterized by the life-threatening inhibition of acetylcholinesterase (AChE) caused by covalent reaction with the serine residue of the active site of the enzyme (phosphylation). Similar reactions occur with butyrylcholinesterase (BChE) and serum albumin present in blood as dissolved proteins. For forensic purposes, products (adducts) with the latter proteins are highly valuable long-lived biomarkers of exposure to OP agents that are accessible by diverse mass spectrometric procedures. In addition, the evidence of poison incorporation might also succeed by the detection of remaining traces of the agent itself, but more likely its hydrolysis and/or enzymatic degradation products. These relatively short-lived molecules are distributed in blood and tissue, and excreted via urine. This review presents the mass spectrometry-based methods targeting the different groups of biomarkers in biological samples, which are already internationally accepted by the Organisation for the Prohibition of Chemical Weapons (OPCW), introduces novel approaches in the field of biomedical verification, and outlines the strict quality criteria that must be fulfilled for unambiguous forensic analysis.

RESUMEN

Oxide Precipitation-Hardened (OPH) alloys are a new generation of Oxide Dispersion-Strengthened (ODS) alloys recently developed by the authors. The mechanical properties of this group of alloys are significantly influenced by the chemical composition and appropriate heat treatment (HT). The main steps in producing OPH alloys consist of mechanical alloying (MA) and consolidation, followed by hot rolling. Toughness was obtained from standard tensile test results for different variants of OPH alloy to understand their mechanical properties. Three machine learning techniques were developed using experimental data to simulate different outcomes. The effectivity of the impact of each parameter on the toughness of OPH alloys is discussed. By using the experimental results performed by the authors, the composition of OPH alloys (Al, Mo, Fe, Cr, Ta, Y, and O), HT conditions, and mechanical alloying (MA) were used to train the models as inputs and toughness was set as the output. The results demonstrated that all three models are suitable for predicting the toughness of OPH alloys, and the models fulfilled all the desired requirements. However, several criteria validated the fact that the adaptive neuro-fuzzy inference systems (ANFIS) model results in better conditions and has a better ability to simulate. The mean square error (MSE) for artificial neural networks (ANN), ANFIS, and support vector regression (SVR) models was 459.22, 0.0418, and 651.68 respectively. After performing the sensitivity analysis (SA) an optimized ANFIS model was achieved with a MSE value of 0.003 and demonstrated that HT temperature is the most significant of these parameters, and this acts as a critical rule in training the data sets.

RESUMEN

Bacillus subtilis is a commonly used commercial specie with broad applications in the fields of bioengineering and biotechnology. B. subtilis is capable of producing both biofilms and spores. Biofilms are matrix-encased multicellular communities that comprise various components including exopolysaccharides, proteins, extracellular DNA, and poly-γ-glutamic acid. These biofilms resist environmental conditions such as oxidative stress and hence have applications in bioremediation technologies. Furthermore, biofilms and spores can be engineered through biotechnological techniques for environmentally-friendly and safe production of bio-products such as enzymes. The ability to withstand with harsh conditions and producing spores makes Bacillus a suitable candidate for surface display technology. In recent years, the spores of such specie are widely used as it is generally regarded as safe to use. Advances in synthetic biology have enabled the reprogramming of biofilms to improve their functions and enhance the production of value-added products. Globally, there is increased interest in the production of engineered biosensors, biocatalysts, and biomaterials. The elastic modulus and gel properties of B. subtilis biofilms have been utilized to develop living materials. This review outlines the formation of B. subtilis biofilms and spores. Biotechnological engineering processes and their increasing application in bioremediation and biocatalysis, as well as the future directions of B. subtilis biofilm engineering, are discussed. Furthermore, the ability of B. subtilis biofilms and spores to fabricate functional living materials with self-regenerating, self-regulating and environmentally responsive characteristics has been summarized. This review aims to resume advances in biological engineering of B. subtilis biofilms and spores and their applications.

RESUMEN

Accumulation and exposure of organophosphate pesticides are of great concern today owing to their abundant usage and potential health hazards. Harmful effects of organophosphate pesticide exposure and limitations of the available treatment methods necessitate the development of reliable, selective, cost-effective, and sensitive methods of detection. We developed a novel biosensor based on the enzymatic action of recombinant organophosphorus hydrolase (OPH) expressed in E. coli. We report the development of colorimetric biosensors made of His-Nus-OPH as well as His-Nus-OPH loaded alginate microspheres. The colorimetric detection method developed using solution-phase and alginate-encapsulated His-Nus-OPH exhibited detection limits of 0.045 and 0.039 mM, respectively, for ethyl paraoxon, and 0.101 and 0.049 mM, respectively, for methyl parathion. Additionally, fluorescence measurement using pH-sensitive fluorescein isothiocyanate (FITC) was used to sense the quantity of organophosphorus pesticides. The fluorometric detection method using solution-phase His-Nus-OPH, with ethyl paraoxon and methyl parathion as the substrate, reveals the lower limit of detection as 0.014 mM and 0.044 mM, respectively. Our results demonstrate the viability of His-Nus-OPH for OP detection with good sensitivity, LOD, and linear range. We report the first use of N-terminal His-NusA-tagged OPH, which enhances solubility significantly and presents a significant advance for the scientific community.

Asunto(s)

Arildialquilfosfatasa/genética , Escherichia coli/genética , Compuestos Organofosforados/análisis , Plaguicidas/análisis , Proteínas Recombinantes/genética , Arildialquilfosfatasa/metabolismo , Técnicas Biosensibles/métodos , Escherichia coli/metabolismo , Metil Paratión/análisis , Proteínas Recombinantes/metabolismo

RESUMEN

Nanocapsuling organophosphorus hydrolase (OPH) is a promising strategy, which can improve OPH stability and put it into practical application. Nanocapsule can protect OPH from deactivation, but on the other hand it may block the contact of enzymes and substrates to some extent. Thus, it is worth exploring the influences of nanocapsule density on the enzyme activity and stability. In this study, OPH surface was modified by N-acryloxysuccinimide (NAS), and then the in situ radical polymerization technique was applied to construct a polymer shell around the surface to form the OPH nanocapsule (nOPH). Transmission electron microscope (TEM) and Fourier Transform Infrared (FTIR) was used to characterize the structure of nOPH. The nOPH activity is not influenced by the presence of nanocapsule when the feed ratio of NAS to OPH is below 75. On the contrary, it decreases with the increasing of NAS feed ratio when it is above 75. Furthermore, nOPH activities at high temperatures and in 20% DMSO solutions both first increase and then decrease with the increasing of NAS feed ratio. The results showed that the appropriate density of the nanocapsule could retain the enzyme activity to the maximum extent during the preparation of nOPH nanocapsule, and significantly improve its thermal stability and organic solvent stability. Hence, the results are of great significance to further realize the OPH practical application.

RESUMEN

The microstructure, mechanical, tribological, and corrosion properties of Fe-Cr-Al-Y-based oxide-precipitation-hardened (OPH) alloy at room temperature are presented. Two OPH alloys with a composition of 0.72Fe-0.15Cr-0.06Al-0.03Mo-0.01Ta-0.02Y2O3 and 0.03Y2O3 (wt.%) were prepared by mechanical alloying with different milling times. After consolidation by hot rolling, the alloys presented a very fine microstructure with a grain size of approximately 180 nm. Such a structure is relatively brittle, and its mechanical properties are enhanced by heat treatment. Annealing was performed at three temperatures (1000 °C, 1100 °C, and 1200 °C), with a holding time from 1 to 20 h. Tensile testing, wear testing, and corrosion testing were performed to evaluate the effect of heat treatment on the behavior and microstructural properties. The grain size increased almost 10 times by heat treatment, which influenced the mechanical properties. The ultimate tensile strength increased up to 300% more compared to the initial state. On the other hand, heat treatment has a negative effect on corrosion and wear resistance.

RESUMEN

Due to high contamination of organophosphate (OP) insecticides in agricultural products and the environment, efficient and convenient devices for their monitoring are necessary. Here, a simple, inexpensive, efficient, and easy-to-use absorbance-based biosensor was fabricated utilizing recombinant methyl parathion hydrolase fused with glutathione-S-transferase (MPH-GST), covalently immobilized onto a chitosan film-coated polystyrene microplate, for the detection of methyl parathion (MP) as a representative of OPs. Having been connected to the transducer system designed to work through an Arduino microcontroller, the biosensor could detect MP as efficiently as the conventional methods, with the detection limit of 0.1 µM, the lowest value ever reported for this method. It was stable at 25 °C for 30 days, could function 100 rounds repetitively, and yielded high recovery with real samples. Hence, this simply designed MPH-GST biosensor could be an easy and inexpensive alternative for efficient OP screening at site to help control its contamination.

RESUMEN

Objective: To investigate the suitability of urinary collagen type-II C-terminal cleavage neoepitope (uC2C) as a marker for early knee osteoarthritis (kOA). Design: We examined 302 Estonian subjects (mean age, 49 years): 186 subjects with and 20 control subjects without knee symptoms, and 96 patients treated by arthroscopy. For the latter, cartilage lesions were characterized using Société Francaise d'Arthroscopie (SFA) scores. Standardized radiographs of bilateral tibiofemoral (TF) and patellofemoral (PF) joints were assessed for osteoarthritis (OA) features. Osteophytes (Ophs) and joint space narrowing (JSN) were graded separately. uC2C was measured by the uC2C-HUSA assay. Logistic and linear regression models were used for data analysis. Results: Of the kOA cases, 50% were isolated (TF or PF) grade 1; 10% were grade 2. JSN with Ophs was more frequent in females than in males (52% vs. 34%, p = 0.01). Increased uC2C level was associated with gradual increase in the risk of kOA grade of severity (odds ratio = 2.14-3.7) including grade 1 vs. 0. TF-OA and PF-OA equally predicted uC2C concentration (R 2 = 0.33-0.35). uC2C prediction was better for females than for males (R 2 = 0.42 vs. 0.22 by TF-OA). The best predictive model for uC2C level (R 2 = 0.75) included three OA features: macroscopic cartilage lesions, TF Ophs, and PF-JSN. Conclusions: uC2C as an integrative marker of kOA is associated with cartilage degradation and Oph formation in the PF- and TF-joints. Increased uC2C concentration could be used as an early diagnostic marker for kOA in clinical studies.

RESUMEN

Agricultural advancements focusing on increasing crop production have led to excessive usage of insecticides and pesticides, resulting in leaching and accumulation of these highly toxic chemicals in soil, water, and the food-chain. Organophosphorus (OP) compounds are the most commonly used insecticides and pesticides, which cause a wide range of long-lasting and life-threatening conditions. Due to the acute toxicity and long-term side effects of OP compounds, their timely, on-the-spot and rapid detection has gained importance, for efficient healthcare management. In this respect, several OP degrading enzymes have gained the spotlight in developing the enzyme-based biosensors, owing to their high activity and broad specificity. Among these enzymes, organophosphorus hydrolase (OPH) has emerged as a promising candidate for the detection of OP compounds, due to its ability to act on a broad range of substrates having a variety of bonds, like P─F, P─O, P─S, and P─CN. Various techniques employing OPH in free/immobilized/conjugated forms into sensing devices were reported to accurately detect OP compounds. The transduction mechanisms of bio-sensing are electrochemical, optical as well as novel methods like magnetoelastic/surface plasmon resonance. Furthermore, to improve the detection limits and sensitivity, nanoparticles and quantum dots are often employed in conjunction with OPH. Here, we highlight the recent advances in sensing OP compounds using OPH based biosensors, compare specifications of sensing methods, and evaluate the influence of different materials used in developing sensors. This review will also enable researchers to design and configure highly sensitive and accurate sensing systems, leading to the development of point-of-care devices for real-time analysis.

Asunto(s)

Arildialquilfosfatasa/metabolismo , Técnicas Biosensibles/métodos , Contaminantes Ambientales/análisis , Compuestos Organofosforados/análisis , Contaminantes Ambientales/toxicidad , Compuestos Organofosforados/toxicidad , Plaguicidas

RESUMEN

Organophosphorus (OP) pesticides have been used widely as agricultural and household pest control agents for almost five decades and persist in our water resources, fruits, vegetables and processed food as health and environmental hazardous compounds. Thus, detection of these harmful OP pesticides at an ease with high sensitivity and selectivity is the need of hour. Bio-sensing technology meet these requirements and has been employed at a large scale for detection. The present review is aimed mainly to provide the overview of the past and recent advances occurred in the field of biosensor technology employed for the detection of these OP compounds. The review describes the principle and strategy of various OP biosensors including electrochemical (amperometric, potentiometric), thermal, piezoelectric, optical (fluorescence, Surface Plasmon Resonance (SPR)), microbial and DNA biosensors in detail. The electrochemical biosensors are generally, based on inhibition of enzyme, acetyl cholinesterase (AChE), butyryl cholinesterase (BChE), tyrosinase and alkaline phosphatase or enzyme (organophosphorus hydrolase, OPH)) catalyzed reaction. The detection limits and linearity range of various OP biosensors have also been compared. AChE inhibition based amperometric OP biosensors exhibited the lowest detection limit of 1 × 10-11 µM with a linearity range of 1.0 × 10-11 - 1.0 × 10-2 µM.

Asunto(s)

Técnicas Biosensibles/métodos , Compuestos Organofosforados/análisis , Plaguicidas/análisis , Animales , Biocatálisis , Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Humanos , Espectrometría de Fluorescencia/instrumentación , Espectrometría de Fluorescencia/métodos

RESUMEN

Our study aims to investigate the physiological role of organophosphate hydrolase (OPH), hitherto known for its involvement in the degradation of organophosphate insecticides and nerve agents in Sphingobium fuliginis. We find that OPH exists as part of the TonB-dependent Transport system that is involved in nutrient transport across the bacterial outer membrane. OPH interacts physically with the Ton complex components ExbD and TonB. The surface-exposed arginine residues (R91 and R96) of OPH facilitate its interaction with ExbD. OPH is targeted to the inner membrane of Escherichia coli only when it is co-expressed with either ExbD or the ExbB/ExbD complex. In the absence of ExbD, OPH remains in the cytoplasm. Our findings suggest a role for OPH in outer membrane transport.

Asunto(s)

Proteínas Bacterianas/química , Proteínas de Escherichia coli/química , Proteínas de la Membrana/química , Organofosfonatos/química , Monoéster Fosfórico Hidrolasas/química , Sphingomonadaceae/enzimología , Arginina/química , Arginina/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Membrana Celular/química , Membrana Celular/enzimología , Clonación Molecular , Citoplasma/química , Citoplasma/enzimología , Escherichia coli/enzimología , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Hidrólisis , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Organofosfonatos/metabolismo , Monoéster Fosfórico Hidrolasas/genética , Monoéster Fosfórico Hidrolasas/metabolismo , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Sphingomonadaceae/genética , Especificidad por Sustrato , Termodinámica

RESUMEN

OBJECTIVE: To contrast the clinical effects and complications for the treatment of liver carcinoma in laparoscopic partial hepatectomy (LPH) and open partial hepatectomy (OPH). METHODS: The multiple databases were adopted to search relevant studies, and the articles eventually satisfying the inclusion criteria were included. All the meta-analyses were conducted with the Review Manager 5.3, and to estimate the quality of each article risk of bias table was performed. RESULTS: In the end, 17 studies including 3897 patients were involved, which eventually satisfied the eligibility criteria. The number of samples in LPH group and OPH group were 1723 and 2174, respectively. The results of heterogeneity test suggested that recurrence rate (odds ratio [OR] = -20.11, 95% confidence interval, CI [-35.93 to -4.29], P = .01; P for heterogeneity <.00001, I2 = 100%), hospital days (mean difference (MD) = -2.21, 95% CI [-2.53 to -1.88], P < .000001; P for heterogeneity = .41, I2 = 58%), and blood loss (MD = -68.09, 95% CI [-85.07 to -51.11], P < .00001; P for heterogeneity = .13, I2 = 37%) were significantly different, whereas operating time (MD = 4.00, 95% CI [-17.50 to 25.49], P = .72; P for heterogeneity <.00001, I2 = 99%) and complication events (OR = 0.68, 95% CI [0.46 to 1.01], P = .05; P for heterogeneity = .34, I2 = 11%) between LPH and OPH were insignificantly different. CONCLUSION: This study demonstrated that clinical efficacy of OPH was better than that of LPH to some extent, but LPH was a quicker recovery and less harmful therapy.

Asunto(s)

Carcinoma Hepatocelular/cirugía , Hepatectomía/métodos , Laparoscopía , Neoplasias Hepáticas/cirugía , Recurrencia Local de Neoplasia , Pérdida de Sangre Quirúrgica , Carcinoma Hepatocelular/patología , Hepatectomía/efectos adversos , Humanos , Laparoscopía/efectos adversos , Tiempo de Internación , Neoplasias Hepáticas/patología , Tempo Operativo , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento

RESUMEN

Necroptosis is a manner of caspase-independent cell death,which accounts for delayed ischemic cerebral injury, and can be used as a novel tool to expand the treatment time window in ischemic cerebral injury. Q-VD-OPH, a novel pan caspase inhibitor, has been identified as an inducer of necroptosis. In this study, we determined the optimal dose of Q-VD-OPH, which induces necroptosis in rats by the middle cerebral artery occlusion, followed by reperfusion. Furthermore, we report that the NLRP3 inflammasome is involved in necroptosis, with levels of NLRP3 inflammasome proteins as well as inflammatory cytokines, such as IL-1ß, being elevated. We also demonstrated that NLRP3 was not only expressed in microglia and vascular endothelial cell, but also in neurons when necroptosis is induced with Q-VD-OPH. Inhibition of NLRP3 by glyburide strongly suppressed the expression of NLRP3 inflammasome proteins and IL-1ß, and markedly reduced brain tissue damage. Our findings provide evidence that pretreatment with Q-VD-OPH suppresses apoptosis and induces necroptosis in the cerebral ischemia-reperfusion model. We also identified that the NLRP3 inflammasome plays an important role in neuronal necroptosis, and that NLRP3 inflammasome deficiency reduces brain tissue damage after cerebral ischemia-reperfusion injury in rats.

Asunto(s)

Clorometilcetonas de Aminoácidos/toxicidad , Apoptosis/efectos de los fármacos , Isquemia Encefálica/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/biosíntesis , Quinolinas/toxicidad , Daño por Reperfusión/metabolismo , Animales , Apoptosis/fisiología , Isquemia Encefálica/inducido químicamente , Isquemia Encefálica/patología , Gliburida/farmacología , Inflamasomas/biosíntesis , Masculino , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Necrosis/inducido químicamente , Necrosis/metabolismo , Necrosis/patología , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/inducido químicamente , Daño por Reperfusión/patología

RESUMEN

Flexible epidermal tattoo and textile-based electrochemical biosensors have been developed for vapor-phase detection of organophosphorus (OP) nerve agents. These new wearable sensors, based on stretchable organophosphorus hydrolase (OPH) enzyme electrodes, are coupled with a fully integrated conformal flexible electronic interface that offers rapid and selective square-wave voltammetric detection of OP vapor threats and wireless data transmission to a mobile device. The epidermal tattoo and textile sensors display a good reproducibility (with RSD of 2.5% and 4.2%, respectively), along with good discrimination against potential interferences and linearity over the 90-300mg/L range, with a sensitivity of 10.7µA∙cm3∙mg-1 (R2 = 0.983) and detection limit of 12mg/L in terms of OP air density. Stress-enduring inks, used for printing the electrode transducers, ensure resilience against mechanical deformations associated with textile and skin-based on-body sensing operations. Theoretical simulations are used to estimate the OP air density over the sensor surface. These fully integrated wearable wireless tattoo and textile-based nerve-agent vapor biosensor systems offer considerable promise for rapid warning regarding personal exposure to OP nerve-agent vapors in variety of decentralized security applications.

Asunto(s)

Aire/análisis , Técnicas Biosensibles/instrumentación , Agentes Nerviosos/análisis , Compuestos Organofosforados/análisis , Dispositivos Electrónicos Vestibles , Tecnología Inalámbrica/instrumentación , Arildialquilfosfatasa/química , Electrodos , Diseño de Equipo , Humanos , Límite de Detección , Reproducibilidad de los Resultados , Textiles , Volatilización