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1.
Langmuir ; 39(44): 15465-15473, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37882466

RESUMEN

LaMn0.5Cu0.5O3 (LMC) as the parent perovskite and Pd- and Pt-doped LaMn0.5Cu0.5O3 catalysts (LMCPd and LMCPt) instead of Cu were synthesized in a new solid-state synthesis technique at a low temperature. Perovskite lattice formation of the LMC catalyst was successfully performed at 600 °C. All perovskites were investigated by X-ray diffraction, HRTEM, O2-TPD, H2-TPR, BET, and XPS analyses. The prepared perovskites were used as heterogeneous catalysts for CO oxidation and methane combustion reactions. The catalytic performance of the LMC catalyst was noticeably enhanced via Pd and Pt substitution instead of Cu. The enhancement in the mobility of lattice oxygen and specific surface area has triggered this catalytic performance improvement, which play an important role in CO oxidation and methane combustion. The Mn 2p and Mn 3s XPS spectra showed that by doping Pd and Pt in the LMC perovskite, Mn was affected in different states and the Mn 3s peaks were only observed in the LMCPt catalyst. XPS spectra of the LMCPd1 sample showed a high oxidation state of Pd3+ or Pd4+, from which it can be concluded that Pd was successfully incorporated into the LMC perovskite lattice. The H2-TPR profiles of the LMCPd and LMCPt perovskites revealed that the reduction peaks of Cu and Mn were shifted to lower temperatures by increasing Pd and Pt partial substitution due to the synergetic effect of the cation and the H2-spillover effect of palladium and platinum.

2.
Nanotechnology ; 34(31)2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37141862

RESUMEN

Titanium dioxide nanotubes (TNT) are widely researched materials for the photocatalytic generation of free radicals, which are useful in wastewater treatment. We aimed to prepare Mo-doped TNT sheets, covered with a cellulose membrane to avoid TNT surface inactivation by protein adsorption. We studied the susceptibility of serum albumin (SA) bound to different molar ratios of palmitic acid (PA) to denaturation and fibrillation by this system, which is meant to mimic oxidative stress conditions such as non-alcoholic fatty liver disease. The results demonstrated that cellulose membrane-covered TNT successfully oxidized the SA, identified by structural changes to the protein. Increasing the molar ratio of PA to protein-enhanced thiol group oxidation while protecting the protein against structural changes. Finally, we propose that in this photocatalyzed oxidation system, the protein is oxidized by a non-adsorptive mechanism mediated by H2O2. Therefore, we suggest that this system could be used as a sustained oxidation system to oxidize biomolecules as well as potentially in wastewater treatment.


Asunto(s)
Peróxido de Hidrógeno , Nanotubos , Oxidación-Reducción , Estrés Oxidativo , Nanotubos/química , Titanio/química
3.
Chem Soc Rev ; 50(18): 10116-10211, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34542117

RESUMEN

Oxide perovskites have emerged as an important class of materials with important applications in many technological areas, particularly thermocatalysis, electrocatalysis, photocatalysis, and energy storage. However, their implementation faces numerous challenges that are familiar to the chemist and materials scientist. The present work surveys the state-of-the-art by integrating these two viewpoints, focusing on the critical role that defect engineering plays in the design, fabrication, modification, and application of these materials. An extensive review of experimental and simulation studies of the synthesis and performance of oxide perovskites and devices containing these materials is coupled with exposition of the fundamental and applied aspects of defect equilibria. The aim of this approach is to elucidate how these issues can be integrated in order to shed light on the interpretation of the data and what trajectories are suggested by them. This critical examination has revealed a number of areas in which the review can provide a greater understanding. These include considerations of (1) the nature and formation of solid solutions, (2) site filling and stoichiometry, (3) the rationale for the design of defective oxide perovskites, and (4) the complex mechanisms of charge compensation and charge transfer. The review concludes with some proposed strategies to address the challenges in the future development of oxide perovskites and their applications.

4.
Molecules ; 26(24)2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-34946740

RESUMEN

Oxidative stress is the leading player in the onset and development of various diseases. The Keap1-Nrf2 pathway is a pivotal antioxidant system that preserves the cells' redox balance. It decreases inflammation in which the nuclear trans-localization of Nrf2 as a transcription factor promotes various antioxidant responses in cells. Through some other directions and regulatory proteins, this pathway plays a fundamental role in preventing several diseases and reducing their complications. Regulation of the Nrf2 pathway occurs on transcriptional and post-transcriptional levels, and these regulations play a significant role in its activity. There is a subtle correlation between the Nrf2 pathway and the pivotal signaling pathways, including PI3 kinase/AKT/mTOR, NF-κB and HIF-1 factors. This demonstrates its role in the development of various diseases. Curcumin is a yellow polyphenolic compound from Curcuma longa with multiple bioactivities, including antioxidant, anti-inflammatory, anti-tumor, and anti-viral activities. Since hyperglycemia and increased reactive oxygen species (ROS) are the leading causes of common diabetic complications, reducing the generation of ROS can be a fundamental approach to dealing with these complications. Curcumin can be considered a potential treatment option by creating an efficient therapeutic to counteract ROS and reduce its detrimental effects. This review discusses Nrf2 pathway regulation at different levels and its correlation with other important pathways and proteins in the cell involved in the progression of diabetic complications and targeting these pathways by curcumin.


Asunto(s)
Antioxidantes/uso terapéutico , Curcumina/uso terapéutico , Complicaciones de la Diabetes , Hipoxia , Transducción de Señal/efectos de los fármacos , Animales , Complicaciones de la Diabetes/tratamiento farmacológico , Complicaciones de la Diabetes/metabolismo , Humanos , Hipoxia/tratamiento farmacológico , Hipoxia/etiología , Hipoxia/metabolismo
5.
Water Sci Technol ; 84(9): 2394-2405, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34810319

RESUMEN

In this research, natural bentonite and its acid-activated forms were employed as adsorbents for the adsorption of Ni2+ ions from wastewater. Natural bentonite was activated with 2 M sulfuric acid, 4.5 h and 95 °C (the best acid-activated sample with the highest adsorption capacity) and the other 6 M sulfuric acid, 7.5 h and 95 °C (the worst acid-activated sample with the lowest adsorption capacity). The adsorption of Ni2+ was studied through experiments including equilibrium contact time and selectivity. The equilibrium contact time for bentonite was obtained at 180 min. The Ni2+ separation process along with Zn2+ selectivity studies was considered through adsorption experiments. The results showed that there was a maximum amount of Ni2+ adsorption in the absence of Zn2+ for all samples. The results showed the best fit is obtained with the pseudo-second-order kinetic model. Working out different bentonite types to determine the best kinetic models, we explored the Langmuir and Florry-Huggins models provided a good fit with experimental data for acid-activated bentonites and the best results from linear forms of the adsorption isotherm models for fitting the experimental data of natural bentonite are obtained for Langmuir, Temkin and Freundlich models.


Asunto(s)
Contaminantes Químicos del Agua , Adsorción , Bentonita , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Contaminantes Químicos del Agua/análisis
6.
World J Urol ; 37(9): 1959-1964, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30535714

RESUMEN

PURPOSE: Local injection of platelet-rich plasma (PRP) is postulated to work by delivering growth factors and cytokines that recruit healer cells and enhance recovery process at the injection site. As new scar formation leads to stricture recurrence after internal urethrotomy, we proposed to improve post-internal urethrotomy stricture recurrence rate by injecting local submucosal PRP at the time of urethrotomy. METHODS: From July 2015 to June 2018, 87 male patients with symptomatic bulbar urethral stricture (diagnosed by retrograde urethrography) randomized into two groups of internal urethrotomy and submucosal normal saline injection (control group, 43 patients), and internal urethrotomy with submucosal autologous platelet-rich plasma injection (PRP injection group, 44 patients). According to the endpoint, which happened sooner, each patient was followed at 3-month intervals for 2 years after internal urethrotomy or until urethral stricture recurrence. RESULTS: Twelve-month recurrence rates were 26.82 and 9.09% in the control and the PRP injection groups, respectively (p 0.032). After 2 years of follow-up, stricture recurrence was identified in 18 (43.90%) and 9 (21.95%) patients in the control and the PRP injection groups, respectively (p 0.34). CONCLUSION: In our study, submucosal PRP injection at the site of internal urethrotomy decreased the rate of stricture recurrence a year after the intervention. This protective effect lasted for 24 months, at least. Submucosal PRP injection at the time of internal urethrotomy also decreased the length of stricture in case of recurrence.


Asunto(s)
Plasma Rico en Plaquetas , Estrechez Uretral/terapia , Adulto , Humanos , Inyecciones Intralesiones , Masculino , Persona de Mediana Edad , Recurrencia , Método Simple Ciego , Estrechez Uretral/cirugía , Adulto Joven
7.
Biotechnol Appl Biochem ; 66(4): 537-544, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30993734

RESUMEN

Amyloid fibrils, including ß-amyloid (Aß) fibrils, are protein aggregates that form under certain conditions, associated with neurodegeneration that interfere with neural synaptic transmission resulting in some neural disorders, such as Alzheimer's disease. The aim of this study is to inhibit amyloidogenesis by using preparatory polymeric nanomicelles as therapeutic agents and also as nanocarriers for curcumin to target Aß fibrils through the glycation method of bovine serum albumin (BSA) in the presence of phosphate-buffered saline. Polymeric nanomicelles were prepared from phosphatidylethanolamine-distearoyl methoxypolyethylene glycol conjugates in the presence and absence of curcumin and then the morphological and structural characteristics of the nanomicelles were characterized in detail. Following the preparation of unloaded and curcumin-loaded nanomicelles with the desired size and properties, their effects on BSA glycation/fibrillation process were investigated. The samples were analyzed by thioflavin T (ThT) fluorescence and advanced glycation end (AGE) products autofluorescence measurements. The results showed that ThT fluorescence related to the formation of ß-sheets and AGE autofluorescence (associated with AGE production) decreased in the presence of curcumin-loaded nanomicelles more than other samples. In conclusion, the promising effect of curcumin-loaded nanomicelles on inhibition of amyloidogenesis through glycation process due to curcumin release and thus their ability to prevent the formation and accumulation of amyloid fibrils and so to suppress the Alzheimer's disease progression has been proven and can go for further investigations.


Asunto(s)
Amiloide/antagonistas & inhibidores , Curcumina/farmacología , Nanopartículas/química , Polímeros/farmacología , Amiloide/metabolismo , Animales , Bovinos , Curcumina/síntesis química , Curcumina/química , Glicosilación , Micelas , Tamaño de la Partícula , Polímeros/síntesis química , Polímeros/química , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/metabolismo , Propiedades de Superficie
8.
J Insect Sci ; 19(2)2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30822779

RESUMEN

Exorista larvarum (L.), a polyphagous gregarious larval parasitoid of lepidopterans, can be mass produced both in vivo, using the greater wax moth Galleria mellonella (L.) (Lepidoptera: Pyralidae) as a factitious host, and in vitro, on artificial media composed of crude components. The present study was focused on another aspect of E. larvarum rearing, namely the influence of adult food on parasitoid performance. The standard food, consisting of lump sucrose and cotton balls soaked in a honey and water solution (1), was compared with other foods or food combinations, namely lump sucrose alone (2), honey and water solution (3), sucrose and water solution either alone (4) or combined with bee-collected pollen (5), and, finally, pollen alone (6). All foods were provided together with distilled water supplied in drinking troughs. Based on the parameters considered (i.e., female longevity, number of eggs laid on host larvae, puparia obtained from eggs, and adults emerged from puparia), pollen alone was deemed to be the most suitable food for adult females of E. larvarum. In particular, the pollen showed a longevity-promoting effect, increasing the number of eggs laid on host larvae throughout the female lifespan. The use of this adult food may also result in a higher flexibility of the management of E. larvarum colonies because it can be replaced weekly, as no desiccation or mold infections were ever found to occur.


Asunto(s)
Dípteros/fisiología , Control de Insectos/métodos , Mariposas Nocturnas/parasitología , Control Biológico de Vectores/métodos , Animales , Dieta , Dípteros/crecimiento & desarrollo , Femenino , Larva/crecimiento & desarrollo , Larva/parasitología , Larva/fisiología , Longevidad , Mariposas Nocturnas/crecimiento & desarrollo , Reproducción
9.
Inflammopharmacology ; 25(4): 451-458, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28391389

RESUMEN

PURPOSE: Inflammation and Cyclooxygenase-2 (COX-2) as a part of it are common in BPH specimens and may play a role in the pathogenesis of the disease through cytokines that promote cell growth or lead to smooth muscle contraction. The aim of this study is to analyze whether combination therapy with omega-3 fatty acids, which have anti-inflammatory and COX-2 inhibitory effects, and tamsulocin plus finasteride offers an advantage compared to tamsulocin plus finasteride therapy in patients with BPH. MATERIALS AND METHODS: This is a single-center blinded clinical trial. One hundred consecutive men between 50 and 70 years of age and no other comorbidities with LUTS and BPH were entered into the study and were randomized to receive omega-3 fatty acids 300 mg three times a day with meals plus tamsulocin 0.4 mg at bed time and finasteride 5 mg/day (study group) versus tamsulocin 0.4 mg at bed time and finasteride 5 mg/day (control group) for 6 months. The efficacy and safety of treatments were assessed at baseline and at month one, three and six. RESULTS: In our population, both treatments (groups study and control) produced statistically significant improvements in IPSS, Q max, Q ave and prostate volume from baseline during follow-up (p < 0.05). We found that study group showed higher improvement in IPSS (p = 0.007), Q max (p = 0.011) and Q ave (p = 0.004) at the 1 month interval. These higher improvements last at month three and six (p < 0.05). Prostate volume in the study group also showed more improvement at month six (p = 0.000). Adverse effects were the same in both groups during the study. CONCLUSION: It can be concluded that association of omega-3 fatty acids with tamsulocin and finasteride may produce better clinical results.


Asunto(s)
Ácidos Grasos Omega-3/administración & dosificación , Finasterida/administración & dosificación , Síntomas del Sistema Urinario Inferior/tratamiento farmacológico , Hiperplasia Prostática/tratamiento farmacológico , Sulfonamidas/administración & dosificación , Agentes Urológicos/administración & dosificación , Antagonistas de Receptores Adrenérgicos alfa 1/administración & dosificación , Anciano , Quimioterapia Combinada , Humanos , Síntomas del Sistema Urinario Inferior/complicaciones , Síntomas del Sistema Urinario Inferior/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/diagnóstico , Método Simple Ciego , Tamsulosina , Resultado del Tratamiento
10.
Biochim Biophys Acta ; 1854(10 Pt A): 1307-16, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26004089

RESUMEN

In this project, we studied some physicochemical properties of two different globin domains of the polymeric hemoglobin of the brine shrimp Artemia salina and compared them with those of the native molecule. Two domains (AsHbC1D1 and AsHbC1D5) were cloned and expressed in BL21(DE3)pLysS strain of Escherichia coli. The recombinant proteins as well as the native hemoglobin (AfHb) were purified from bacteria and frozen Artemia, respectively by standard chromatographic methods and assessed by SDS-PAGE. The heme environment of these proteins was studied by optical spectroscopy and ligand-binding kinetics (e.g. CO association and O2 binding affinity) were measured for the two recombinant proteins and the native hemoglobin. This indicates that the CO association rate for AsHbC1D1 is higher than that of AsHbC1D5 and AfHb, while the calculated P50 value for AsHbC1D1 is lower than that of AsHbC1D5 and AfHb. The geminate and bimolecular rebinding parameters indicate a significant difference between both domains. Moreover, EPR results showed that the heme pocket in AfHb is in a more closed conformation than the heme pocket in myoglobin. Finally, the reduction potential of -0.13V versus the standard hydrogen electrode was determined for AfHb by direct electrochemical measurements. It is about 0.06V higher than the potential of the single domain AsHbC1D5. This work shows that each domain in the hemoglobin of Artemia has different characteristics of ligand binding.


Asunto(s)
Artemia/química , Proteínas de Artrópodos/química , Monóxido de Carbono/química , Hemo/química , Hemoglobinas/química , Oxígeno/química , Secuencia de Aminoácidos , Animales , Artemia/metabolismo , Proteínas de Artrópodos/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Hemoglobinas/genética , Cinética , Modelos Moleculares , Datos de Secuencia Molecular , Oxidación-Reducción , Polimerizacion , Unión Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Alineación de Secuencia , Termodinámica
11.
Extremophiles ; 18(1): 25-33, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24122359

RESUMEN

A halophilic archaeon, Halorubrum sp. strain Ha25, produced extracellular halophilic organic solvent-tolerant amylopullulanase. The maximum enzyme production was at high salt concentration, 3-4 M NaCl. Optimum pH and temperature for enzyme production were 7.0 and 40 °C, respectively. Molecular mass of purified enzyme was estimated to be about 140 kDa by SDS-PAGE. This enzyme was active on pullulan and starch as substrates. The apparent Km for the enzyme activity on pullulan was 4 mg/ml and for soluble starch was 1.8 mg/ml. Optimum temperature for amylolytic and pullulytic activities was 50 °C. Optimum pH for amylolytic activity was 7 and for pullulytic activity was 7.5. This enzyme was active over a wide range of concentrations (0-4.5 M) of NaCl. The effect of organic solvents on the enzyme activities showed that this enzyme was more stable in the presence of non-polar organic solvents than polar solvents. This study is the first report on amylopullulanase production in halophilic bacteria and archaea.


Asunto(s)
Proteínas Arqueales/química , Proteínas Bacterianas/química , Glicósido Hidrolasas/química , Halorubrum/enzimología , Proteínas Arqueales/aislamiento & purificación , Proteínas Bacterianas/aislamiento & purificación , Glicósido Hidrolasas/aislamiento & purificación , Calor , Concentración Osmolar , Solventes
12.
Sci Rep ; 14(1): 9659, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671177

RESUMEN

In this study, a series of cobalt-based spinel ferrites catalysts, including nickel, cobalt, zinc, and copper ferrites, were synthesized using the sol-gel auto-combustion method followed by a chemical reduction process. These catalysts were employed for accelerating hydrogen generation via the sodium borohydride hydrolysis process. A continuous stirred tank reactor was used to perform catalytic reactor tests. All samples were subjected to analysis using XRD, FESEM, EDX, FTIR, and nitrogen adsorption-desorption techniques. The results revealed that the cobalt-based copper ferrite sample, Co/Cu-Ferrite, exhibited superior particle distribution, and porosity characteristics, as it achieved a high hydrogen generation rate of 2937 mL/min.gcat. In addition, the higher electrical donating property of Cu-Ferrite which leads to the increase in the electron density of the cobalt active sites can account for its superior performance towards hydrolysis of NaBH4. Using the Arrhenius equation and the zero-order reaction calculation, activation energy for the sodium borohydride hydrolysis reaction on the Co/Cu-Ferrite catalyst was determined to be 18.12 kJ/mol. This low activation energy compared to other cobalt-based spinel ferrite catalysts confirms the catalyst's superior performance as well. Additionally, the outcomes from the recycling experiments revealed a gradual decline in the catalyst's performance after each cycle during 4 repetitive cycles. The aforementioned properties render the Co/Cu-Ferrite catalyst an efficient catalyst for hydrogen generation through NaBH4 hydrolysis.

13.
Sci Rep ; 14(1): 1716, 2024 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-38242928

RESUMEN

Bioactive peptide-based drugs have gained exceeding attention as promising treatments for infectious and oxidative-stress-related diseases, are exacerbated by the advent and spread of various multidrug-resistant bacteria and industrial lifestyles. Fish skin mucus has been recognized as a potential source of bioactive peptides, providing the first line of fish defense against invading pathogens which are targeted here to be explored as a new source of biopharmaceutics. Peptide fractions were isolated from the epidermal exudates of Caspian sand goby, Neogobius fluviatilis pallasi, by solid-phase extraction (SPE), ultrafiltration, and reversed-phase chromatography. The resulting fractions were characterized for their antibacterial and antioxidant properties, and results showed that the molecular weight fraction < 5 kDa represented the highest (p < 0.05) bacterial inhibition activity against Staphylococcus aureus and Bacillus subtilis as well as scavenging activity against DPPH and ABTS radicals. Overall, these results introduce the epidermal mucus of Caspian sand goby as a valuable source of bioactive compounds that can be considered new and efficient biopharmaceutics.


Asunto(s)
Perciformes , Ultrafiltración , Animales , Cromatografía de Fase Inversa , Epidermis , Antioxidantes/química , Péptidos/química , Antibacterianos/química
14.
Int J Biol Macromol ; 249: 126036, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37516225

RESUMEN

Here we present a novel machine-learning approach to predict protein aggregation propensity (PAP) which is a key factor in the formation of amyloid fibrils based on logistic regression (LR). Amyloid fibrils are associated with various neurodegenerative diseases (ND) such as Alzheimer's disease (AD) and Parkinson's disease (PD), which are caused by oxidative stress and impaired protein homeostasis. Accordingly, the paper uses a dataset of hexapeptides with known aggregation tendencies and eight physiochemical features to train and test the LR model. Also, it evaluates the performance of the LR model using F-measure and Matthews correlation coefficient (MCC) as metrics and compares it with other existing methods. Moreover, it investigates the effect of combining sequence and feature information in the prediction. In conclusion, the LR model with sequence and feature information achieves high F-measure (0.841) and MCC (0.6692), outperforming other methods and demonstrating its efficiency and reliability for PAP prediction. In addition, the overall performance of the concluded method was higher than the other known servers, for instance, Aggrescan, Metamyl, Foldamyloid, and PASTA 2.0. The LR model can be accessed at: https://github.com/KatherineEshari/Protein-aggregation-prediction.


Asunto(s)
Amiloide , Agregado de Proteínas , Modelos Logísticos , Reproducibilidad de los Resultados , Aprendizaje Automático
15.
Appl Biochem Biotechnol ; 195(5): 3047-3066, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36508074

RESUMEN

In this study, the chitin of adult Mediterranean flour moth (Ephestia kuheniella) (Cht) was extracted and then converted to chitosan by deacetylation process to achieve the chitosan derived from E. kuheniella (Chsfm). The new chitosan-based scaffold was produced using the polyvinyl alcohol (PVA) co-electrospinning technique. The degree of deacetylation was obtained using the distillation-titration and Fourier transform infrared spectroscopy. The surface morphology and crystallinity index of Chsfm were observed using scanning electron microscopy and X-ray diffraction analysis, respectively, and compared with the commercial chitosan (Chsc). Thermogravimetric analysis was used to estimate two chitosans' water content and thermal stability. The average molecular mass analysis was performed using viscometry. Moreover, the minimum inhibitory concentration and DPPH assay were used to study the antimicrobial activity and antioxidant potential of the Chsfm, respectively. Accordingly, Chsfm was smoother with fewer pores and flakes than Chsc, and its crystallinity index was higher than Chsc. The water content and thermal stability were lower and similar for Chsfm compared to Chsc. The average molecular mass of Chsfm was ~ 5.8 kDa, making it classified as low molecular weight chitosan. The antimicrobial activity of Chsfm against a representative Gram-negative bacteria; E. coli resulted to be the same as Chsc. However, less effective than Chsc against a representative Gram-positive bacteria is S. aureus. The Chsfm/PVA ratio scaffold was optimized at 30:70 to fabricate a uniform nanofiber scaffold.


Asunto(s)
Antiinfecciosos , Quitosano , Mariposas Nocturnas , Animales , Quitosano/farmacología , Quitosano/química , Escherichia coli , Staphylococcus aureus , Antiinfecciosos/farmacología , Agua/química , Alcohol Polivinílico/química , Espectroscopía Infrarroja por Transformada de Fourier
16.
J Mol Graph Model ; 122: 108495, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37116337

RESUMEN

Exploring allosteric inhibition and the discovery of new inhibitor binding sites are important studies in protein regulation mechanisms and drug discovery. Structural and network-based analyses of trajectories resulting from molecular dynamics (MD) simulations have been developed to discover protein dynamics, landscape, functions, and allosteric regions. Here, an experimentally suggested non-competitive inhibitor, xanthene-11v, was considered to explore its allosteric inhibition mechanism in α-glucosidase MAL12. Comparative structural and network analyses were applied to eight 250 ns independent MD simulations, four of which were performed in the free state and four of which were performed in ligand-bound forms. Projected two-dimensional free energy landscapes (FEL) were constructed from the probabilistic distribution of conformations along the first two principal components. The post-simulation analyses of the coordinates, side-chain torsion angles, non-covalent interaction networks, network communities, and their centralities were performed on α-glucosidase conformations and the intermediate sub-states. Important communities of residues have been found that connect the allosteric site to the active site. Some of these residues like Thr307, Arg312, TYR344, ILE345, Phe357, Asp406, Val407, Asp408, and Leu436 are the key messengers in the transition pathway between allosteric and active sites. Evaluating the probability distribution of distances between gate residues including Val407 in one community and Phe158, and Pro65 in another community depicted the closure of this gate due to the inhibitor binding. Six macro states of protein were deduced from the topology of FEL and analysis of conformational preference of free and ligand-bound systems to these macro states shows a combination of lock-and-key, conformational selection, and induced fit mechanisms are effective in ligand binding. All these results reveal structural states, allosteric mechanisms, and key players in the inhibition pathway of α-glucosidase by xanthene-11v.


Asunto(s)
Proteínas , alfa-Glucosidasas , Regulación Alostérica , alfa-Glucosidasas/metabolismo , Ligandos , Simulación de Dinámica Molecular , Proteínas/química , Proteínas/metabolismo
17.
Antioxidants (Basel) ; 12(3)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36978983

RESUMEN

Oxidative stresses (OSs) are considered a pivotal factor in creating various pathophysiological conditions. Cells have been able to move forward by modulating numerous signaling pathways to moderate the defects of these stresses during their evolution. The company of Kelch-like ECH-associated protein 1 (Keap1) as a molecular sensing element of the oxidative and electrophilic stress and nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2) as a master transcriptional regulator of the antioxidant response makes a master cytoprotective antioxidant pathway known as the Keap1/Nrf2 pathway. This pathway is considered a dual-edged sword with beneficial features for both normal and cancer cells by regulating the gene expression of the array of endogenous antioxidant enzymes. Heme oxygenase-1 (HO-1), a critical enzyme in toxic heme removal, is one of the clear state indicators for the duality of this pathway. Therefore, Nrf2/HO-1 axis targeting is known as a novel strategy for cancer treatment. In this review, the molecular mechanism of action of natural antioxidants on lung cancer cells has been investigated by relying on the Nrf2/HO-1 axis.

18.
Daru ; 20(1): 72, 2012 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-23351780

RESUMEN

BACKGROUND AND PURPOSE OF THE STUDY: H. pylori infection is an important etiologic impetus usually leading to gastric disease and urease enzyme is the most crucial role is to protect the bacteria in the acidic environment of the stomach. Then urease inhibitors would increase sensitivity of the bacteria in acidic medium. METHODS: 137 Iranian traditional medicinal plants were examined against Jack bean urease activity by Berthelot reaction. Each herb was extracted using 50% aqueous methanol. The more effective extracts were further tested and their IC50 values were determined. RESULTS: 37 plants out of the 137 crude extracts revealed strong urease inhibitory activity (more than 70% inhibition against urease activity at 10 mg/ml concentration). Nine of the whole studied plants crude extracts were found as the most effective with IC50 values less than 500 µg/ml including; Rheum ribes, Sambucus ebulus, Pistachia lentiscus, Myrtus communis, Areca catechu, Citrus aurantifolia, Myristica fragrans, Cinnamomum zeylanicum and Nicotiana tabacum. CONCLUSIONS: The most potent urease inhibitory was observed for Sambucus ebulus and Rheum ribes extracts with IC50 values of 57 and 92 µg/ml, respectively.

19.
Arch Ital Urol Androl ; 94(2): 150-154, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35775337

RESUMEN

BACKGROUND: Radical cystectomy (RC) has been considered the standard management of muscle-invasive bladder cancer. Despite the improvements in surgical techniques and perioperative care, RC is still associated with high perioperative morbidity and mortality. OBJECTIVE: This study aims to evaluate the effect of retroperitonealization of ureteroileal anastomosis on perioperative complications of RC with ileal conduit urinary diversion. PATIENTS AND METHODS: This is a retrospective cohort study. We reviewed medical charts of 876 patients who underwent RC between 2016 and 2021. Based on the inclusion and exclusion criteria, 748 patients entered the study. According to retroperitonealization of the ureteroileal anastomosis, patients were categorized into two groups (group I without retroperitonealization of the ureteroileal anastomosis and group II with retroperitonealization of the ureteroileal anastomosis). Patients' characteristics and occurrences of any complications and high-grade complications were compared between these groups. RESULTS: In comparing the complication categories between the two groups, fewer patients in group II suffered from gastrointestinal, urinary, and cardiac events (p values were 0.018, 0.021, and 0.013, respectively). Moreover, fewer patients in group II experienced any complications and high-grade complications (p values were < 0.001 and < 0.001, respectively). The length of hospital stay was also significantly shorter in group II (p < 0.001). CONCLUSIONS: RC is associated with comparatively high perioperative morbidity and mortality. In the present study, 61% of the patients experienced at least one complication postoperatively. Retroperitonealization of the ureterointestinal anastomosis may decrease perioperative adverse events of RC with ileal conduit urinary diversion.


Asunto(s)
Uréter , Neoplasias de la Vejiga Urinaria , Derivación Urinaria , Anastomosis Quirúrgica/efectos adversos , Cistectomía/efectos adversos , Cistectomía/métodos , Humanos , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Uréter/cirugía , Neoplasias de la Vejiga Urinaria/etiología , Neoplasias de la Vejiga Urinaria/cirugía , Derivación Urinaria/efectos adversos , Derivación Urinaria/métodos
20.
Sci Rep ; 12(1): 18332, 2022 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-36316461

RESUMEN

The relationship between diabetes mellitus (DM) and Alzheimer's disease (AD) is so strong that scientists called it "brain diabetes". According to several studies, the critical factor in this relationship is brain insulin resistance. Due to the rapid global spread of both diseases, overcoming this cross-talk has a significant impact on societies. Long non-coding RNAs (lncRNAs), on the other hand, have a substantial impact on complex diseases due to their ability to influence gene expression via a variety of mechanisms. Consequently, the regulation of lncRNA expression in chronic diseases permits the development of innovative therapeutic techniques. However, developing a new drug requires considerable time and money. Recently repurposing existing drugs has gained popularity due to the use of low-risk compounds, which may result in cost and time savings. in this study, we identified drug repurposing candidates capable of controlling the expression of common lncRNAs in the cross-talk between DM and AD. We also utilized drugs that interfered with this cross-talk. To do this, high degree common lncRNAs were extracted from microRNA-lncRNA bipartite network. The drugs that interact with the specified lncRNAs were then collected from multiple data sources. These drugs, referred to as set D, were classified in to positive (D+) and negative (D-) groups based on their effects on the expression of the interacting lncRNAs. A feature selection algorithm was used to select six important features for D. Using a random forest classifier, these features were capable of classifying D+ and D- with an accuracy of 82.5%. Finally, the same six features were extracted for the most recently Food and Drug Administration (FDA) approved drugs in order to identify those with the highest likelihood of belonging to D+ or D-. The most significant FDA-approved positive drugs, chromium nicotinate and tapentadol, were presented as repurposing candidates, while cefepime and dihydro-alpha-ergocryptine were recommended as significant adverse drugs. Moreover, two natural compounds, curcumin and quercetin, were recommended to prevent this cross-talk. According to the previous studies, less attention has been paid to the role of lncRNAs in this cross-talk. Our research not only did identify important lncRNAs, but it also suggested potential repurposed drugs to control them.


Asunto(s)
Enfermedad de Alzheimer , Diabetes Mellitus , MicroARNs , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Preparaciones Farmacéuticas , MicroARNs/genética , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/genética
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