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1.
Artigo em Inglês | MEDLINE | ID: mdl-35399644

RESUMO

Acetyl-11-keto-beta-boswellic acid (AKBA), the major component of Boswellia serrata, exhibits anti-inflammatory activities. This in vitro study investigated the protective effects of AKBA against lipopolysaccharide (LPS)-induced cardiac dysfunction. In this study, the H9C2 cardiomyocytes were pretreated with AKBA (2.5, 5, and 10 µM for 24 h), and then cotreated with LPS for another 24 h. The MTT assay, ELISA test kits, and quantitative real-time PCR analysis assessed the cell viability, levels of proinflammatory factors (IL-ß, IL-6, TNF- α, and PGE2), and the gene expression of IL-ß, IL-6, TNF- α, iNOS, and COX-2, respectively. The nitric oxide (NO) and thiol levels were also measured using a biochemical assay. The results indicated that LPS exposure markedly reduced cell viability and total thiol content, but increased the inflammatory cytokines, NO metabolites, and gene expression of proinflammatory mediators in H9C2 cells. AKBA pretreatment significantly altered the mentioned factors induced by LPS. Our results demonstrated that AKBA might be a promising therapeutic agent for treating sepsis-related cardiac dysfunction in the future.

2.
IET Nanobiotechnol ; 13(2): 189-192, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31051450

RESUMO

Silver nanoparticles (AgNPs) have been biosynthesised through the extracts of Ribes khorassanicum fruits, which served as the reducing agents and capping agents. Biosynthesised AgNPs have been found to be ultraviolet-visible (UV-vis) absorption spectra since they have displayed one surface plasmon resonance peak at 438 nm, attesting the formation of spherical NPs. These particles have been characterised by UV-vis, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy analysis. The formation of AgNPs at 1.0 mM concentration of AgNO3 has resulted in NPs that contained mean diameters in a range of 20-40 nm. The green-synthesised AgNPs have demonstrated high antibacterial effect against pathogenic bacteria (i.e. Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa). Biosynthesising metal NPs through plant extracts can serve as the facile and eco-friendly alternative for chemical and/or physical methods that are utilised for large-scale nanometal fabrication in various medical and industrial applications.


Assuntos
Antibacterianos/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Ribes/química , Prata/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Extratos Vegetais/metabolismo , Prata/metabolismo , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Exp Eye Res ; 181: 294-301, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30807745

RESUMO

Limbal stem cell deficiency is a pathological state. Recently, limbal stem cell (LSC) transplantation has attracted great interest as a therapeutic method which mainly involves in-vitro expansion of LSCs. It is believed that ex-vivo cultivation conditions could affect the outcome of surgery and the rate of successful transplantation. Thus, we aimed to define a suitable culture condition by conducting a research on ex-vivo expanded LSCs to maintain an optimized graft of amniotic membrane with cultivated-limbal stem cells, regarding the quantity and quality, with the hope of improving the clinical outcome.


Assuntos
Senescência Celular/fisiologia , Doenças da Córnea/patologia , Limbo da Córnea/patologia , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Alicerces Teciduais , Adulto , Técnicas de Cultura de Células , Proliferação de Células , Doenças da Córnea/terapia , Feminino , Humanos , Imuno-Histoquímica , Limbo da Córnea/metabolismo , Masculino , Estresse Oxidativo , Adulto Jovem
4.
Recent Pat Biotechnol ; 13(3): 228-238, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30657052

RESUMO

BACKGROUND: The green synthesizing procedure of Silver nanoparticles (AgNPs) has been performed through the usage of a natural polysaccharide; Arabic gum (AG) as a stabilizing/ capping agent. For characterization of AgNPs, TEM, particle size analyzer and UV-Vis were used. METHODS: The aim of our project was to identify biosynthesized AgNPs for sensing ammonia and to explore its toxicity on Neuro-2A cells. We also reviewed the patents for biosynthesized AgNO3 and ammonia sensing. The optimal conditions for the synthesis of AgNPs in AG consist of utilizing (0.1g) AG in dH2O (70 ml), 10 ml of 1 mM silver solution and 0.1 mM (AA) at 70°C stirring for 30 minutes. The AgNPs cytotoxicity was evaluated on Neuro-2A cells; consequently, ammonia was sensed with the lowest possible concentration of 10-6. RESULTS: Particle size analyzer displayed the mean diameter of about 70 nm for the sphericalshaped Ag-NPs. UV-Vis revealed that the prepared AgNPs were ammonia sensitive in solution as the concentration of ammonia was increased. The cytotoxicity of AgNPs indicated lower Cell viability at higher concentrations of the AG-capped AgNPs. CONCLUSION: By synthesis of AgNPs in GA by using AA, we successfully prepared a sensor to diagnose ammonia in a cell and sensing its level at concentrations of 10-6 M. In this study, no therapeutic application has been shown, but this method could be utilized industrially for therapeutic purposes in the future.


Assuntos
Amônia/análise , Técnicas Biossensoriais/métodos , Goma Arábica/química , Nanopartículas Metálicas/química , Neurônios/efeitos dos fármacos , Prata/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Verde , Humanos , Limite de Detecção , Nanopartículas Metálicas/ultraestrutura , Camundongos , Neurônios/citologia , Tamanho da Partícula
5.
Med J Islam Repub Iran ; 31: 124, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30159257

RESUMO

Background: Red blood cell distribution width (RDW) is a quantitative measure of variability in the size of circulating erythrocytes. It has been recently identified as a prognostic marker in several diseases including acute pancreatitis (AP). In this systematic review the prognostic value of RDW in predicting mortality of AP patients will be assessed. Methods: PubMed, Scopus, EMBASE, and ISI databases were searched until September 2016 using the following search strategy: (pancreatitis OR pancreatitides) AND (RDW OR "red cell distribution width" OR "red blood cell distribution width" OR anisocytosis). Four authors independently reviewed the retrieved articles. Studies were included if they had evaluated the association between RDW value and mortality of acute pancreatitis patients. Case reports, comments, letters to the editor, reviews, study protocols, and experimental studies were not included. Data abstraction and quality assessment for the included studies was independently performed by two authors. Quality of studies was assessed using Oxford Center for Evidence-Based Medicine checklist for prognostic studies. Data were synthesized qualitatively, and a meta-analysis was performed on the diagnostic performance of RDW to predict mortality in AP patients. Results: Seven studies (976 patients) were included in the systematic review. Six studies reported a statistically significant association between RDW value and mortality. Meta-analysis was performed on four studies (487 patients) using a bivariate model and a summary receiver operating characteristic (sROC) curve was plotted with an area under the curve (AUC) of 0.757. The pooled diagnostic odds ratio (DOR), sensitivity and specificity was 19.51 (95% CI: 5.26-72.30), 67% (95% CI: 51%-80%) and 90% (95% CI: 73%-96%), respectively. Conclusion: RDW is an easy to use and an inexpensive marker with a moderate prognostic value to predict death in AP patients. Clinicians should be more alert when a patient with AP has an increased RDW. Investigation of possible combinations of other prognostic markers with RDW is recommended.

6.
Biophys J ; 102(7): 1483-92, 2012 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-22500748

RESUMO

Biofilms are layers of microbial cells growing on an interface and they can form highly complex structures adapted to a wide variety of environmental conditions. Biofilm streamers have a small immobile base attached to the support and a flexible tail elongated in the flow direction, which can vibrate in fast flows. Herein we report numerical results for the role of the periodical movement of biofilm streamers on the nutrient uptake and in general on the solute mass transfer enhancement due to flow-induced oscillations. We developed what to our knowledge is a novel two-dimensional fluid-structure interaction model coupled to unsteady solute mass transport and solved the model using the finite element method with a moving mesh. Results demonstrate that the oscillatory movement of the biofilm tail significantly increases the substrate uptake. The mass transfer coefficient is the highest in regions close to the streamer tip. The reason for substrate transfer enhancement is the increase in speed of tip movement relative to the surrounding liquid, thereby reducing the thickness of the mass transfer boundary layer. In addition, we show that the relative mass transfer enhancement in unsteady conditions compared with the rigid static structure is larger at higher flow velocities, and this relative increase favors a more flexible structure.


Assuntos
Biofilmes , Modelos Biológicos , Movimento , Hidrodinâmica , Solubilidade
7.
Biotechnol Bioeng ; 107(5): 844-53, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20717977

RESUMO

Optical coherence tomography (OCT) was successfully applied to visualize the mesoscale structure of three different heterotrophic biofilms. For this purpose, biofilm volumes of 4 × 4 × 1.6 mm(3) were scanned with spatial resolutions lower than 20 µm within an acquisition time of 2 min. A heterogeneous structure was detected for biofilms cultivated in laminar as well as transient flow conditions. The structure was found to be more homogeneous for the biofilm grown in turbulent flow. This biofilm structure was characterized by a volumetric porosity of 0.36, whereas the porosity calculated for biofilms grown in laminar and transient conditions was 0.65. These results were directly generated from the distribution of porosity calculated from the OCT images acquired and can be linked to structural properties. Up to now, the mesoscale biofilm structure was only observable with time-consuming and expensive studies, for example, magnetic resonance microscopy. OCT will most certainly be helpful for improved understanding and prediction of biofilm physics with respect to macroscale processes, for example, mass transfer and detachment as the information about mesoscale is easily accessible using this method. In the context of this study, we show that CLSM images do not necessarily provide an accurate representation of the biofilm structure at the mesoscale. Additionally, the typical characteristic parameters obtained from CLSM image stacks differ largely from those calculated from OCT images. Nevertheless, to determine the local distribution of biofilm constituents, microscopic methods such as confocal laser scanning microscopy are required.


Assuntos
Biofilmes/crescimento & desenvolvimento , Tomografia de Coerência Óptica/métodos , Processamento de Imagem Assistida por Computador/métodos , Microscopia Confocal/métodos
8.
Biotechnol Bioeng ; 105(3): 600-10, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19777581

RESUMO

Hydrodynamic conditions have a significant impact on the biofilm lifecycle. Not well understood is the fact that biofilms, in return, also affect the flow pattern. A decade ago, it was already shown experimentally that under fast flows, biofilm streamers form and oscillate with large amplitudes. This work is a first attempt to answer the questions on the mechanisms behind the oscillatory movement of the streamers, and whether this movement together with the special streamlined form of the streamers, have both a physical and biological benefit for biofilms. In this study, a state of the art two-dimensional fluid-structure interaction model of biofilm streamers is developed, which implements a transient coupling between the fluid and biofilm mechanics. Hereby, it is clearly shown that formation of a Kármán vortex street behind the streamer body is the main source of the periodic oscillation of the streamers. Additionally it is shown that the formation of streamers reduces the fluid forces which biofilm surface experiences.


Assuntos
Biofilmes/crescimento & desenvolvimento , Fenômenos Biomecânicos , Movimento (Física) , Rios
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