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1.
Br J Neurosurg ; 35(1): 77-79, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32419506

RESUMEN

BACKGROUND: Collagens are the main components of the extracellular matrix of intervertebral discs. The genetic mutations in collagen genes could potentially play a causal role in pathophysiology of intervertebral disc degeneration (IVDD). In this study, we investigate the association of COL1A1 and COL9A2 single nucleotide polymorphisms (SNPs) with IVDD. MATERIAL AND METHODS: ninety-six Iranian IVDD patients and 94 controls matched for age and sex were included. 5 cc of peripheral blood samples were obtained for DNA extraction using the Phenol-Chloroform method. The primers for SNPs COL1A1 rs909102 and COL9A2 were designed based on the TaqMan protocol and genotyped by real-time PCR with TaqMan. RESULTS: The 'T' allele, 'CC' and 'TT' genotypes of COL1A1 rs909102 were more common among patients, however not significantly. Despite the similar allele distribution of COL9A2 rs137853213 in patients and controls, the homozygote genotypes were more frequent among patients, though this was not significant either. CONCLUSION: The allele and genotype distributions of COL1A1 rs909102 and COL9A2 rs137853213 SNPs were not significantly associated with IVDD in an Iranian population.


Asunto(s)
Degeneración del Disco Intervertebral , Disco Intervertebral , Colágeno Tipo I , Cadena alfa 1 del Colágeno Tipo I , Colágeno Tipo IX/genética , Genotipo , Humanos , Degeneración del Disco Intervertebral/genética , Irán/epidemiología , Polimorfismo de Nucleótido Simple/genética
2.
BMC Med Genet ; 21(1): 143, 2020 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-32620160

RESUMEN

BACKGROUND: Intervertebral disc degeneration (IVDD) is an age-related degenerative disease, presenting with low back pain or radicular pain. The inflammatory changes would occur in discs in the process of IVDD. Therefore, the inflammatory and anti-inflammatory cytokines, as well as their respective genes, have been proposed to play roles in pathophysiology of disease. This study has been conducted to elucidate the role of IL-2, IL-12, and IFN-γ single nucleotide polymorphisms (SNP) in this disease. METHOD: Seventy-six patients who were diagnosed with IVDD and 140 healthy controls who complied with eligibility criteria were included. A total volume of 5 cc peripheral blood was obtained from each participant to investigate the IL-2 + 166G/T, IL-2 -330G/T, IL-12 - 1188A/C, and IFN-γ +847A/T SNPs through PCR-SSP method. RESULTS: The 'TG' and 'TT' genotypes of IL-2 - 330G/T polymorphism were significantly more common among patients and healthy controls respectively. The 'GT' and 'TT' haplotypes of IL-2 (comprised of -330G/T, and + 166G/T SNPs) were also more common among patients and controls respectively. CONCLUSION: This study indicated the significant role of IL-2 genotypes and haplotypes in IVDD. These SNPs were differently distributed in patients and controls. Therefore, alteration in the structure of IL-2 gene could play an important role in pathophysiology of IVDD.


Asunto(s)
Estudios de Asociación Genética , Interferón gamma/genética , Interleucina-12/genética , Interleucina-2/genética , Adulto , Estudios de Casos y Controles , Evaluación de la Discapacidad , Frecuencia de los Genes/genética , Predisposición Genética a la Enfermedad , Humanos , Degeneración del Disco Intervertebral/genética , Irán , Polimorfismo de Nucleótido Simple , Escala Visual Analógica
3.
Br J Neurosurg ; 34(1): 66-71, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32141366

RESUMEN

Background: Intervertebral disc degeneration (IVDD) is a multifactorial disease that is sensitive to the balance between anti-inflammatory and pro-inflammatory cytokines. This study investigated the single nucleotide polymorphisms (SNPs) of interleukin 4 (IL-4) in IVDD.Methods: Genomic DNA of peripheral mononuclear cells of 76 IVDD patients and 140 healthy controls were investigated for three SNPs of IL-4 (rs2243248 (-1098G/T), rs2243250 (-590 C/T), rs2070874 (-33 C/T)) and 1 SNP of IL-4RA (rs180275, +1902 A/G) through PCR-SSP method.Results: The 'C' allele frequency of IL-4 rs2243250 was 104 in 76 patients, while it was 149 in 140 controls (OR = 2, p = .001); also this SNP was significantly associated with post-operative pain reduction. The 'C' allele of IL-4 rs2070874 (130 in 76 patients, and 200 in 140 controls, OR = 2.66), and the 'CC' genotype were more frequent among patients (OR = 3.98, p < .001) than controls. 'TTT' haplotype was more common in controls (OR = 0.36, p < .001) and 'TCC' was also more common in patients (OR = 1.75, p = .012). A meta-analysis of previous studies found significantly higher IL-4 levels in disc tissues of IVDD patients, which was not similarly found in blood samples.Conclusion: The immune system plays an important role in IVDD. The extent and progress of the disease vary significantly with IL-4 level. Meanwhile, the rs2070874 and rs2243250 SNPs of IL-4 were significantly associated with IVDD in Iranian patients.


Asunto(s)
Subunidad alfa del Receptor de Interleucina-4/genética , Interleucina-4/genética , Degeneración del Disco Intervertebral/genética , Adulto , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Interleucina-4/biosíntesis , Subunidad alfa del Receptor de Interleucina-4/biosíntesis , Degeneración del Disco Intervertebral/epidemiología , Irán/epidemiología , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/epidemiología , Dolor Postoperatorio/genética , Polimorfismo de Nucleótido Simple , Adulto Joven
4.
Int J Biol Macromol ; 269(Pt 2): 132186, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723815

RESUMEN

Trigonella foenum-graecum, known as fenugreek, belongs to the leguminous family of wild growth in Western Asia, Europe, the Mediterranean, and Asia; its ripe seeds contain a pool of bioactive substances with great potential in the food industry and medicine. In this study, fenugreek seed mucilage (FSM) was extracted and characterized in its structural properties by X-ray diffraction, nuclear magnetic resonance, and high-performance liquid chromatography. Then, the applicability of FSM as an antimicrobial agent was demonstrated via the development of novel, active, edible FSM-based biofilms containing carboxymethyl cellulose and rosemary essential oil (REO). Incorporating REO in the biofilms brought about specific changes in Fourier-transform infrared spectra, affecting thermal degradation behavior. Scanning electron microscopy and atomic force microscopy morphography showed an even distribution of REO and smoother surfaces in the loaded films. Besides, the solubility tests evidenced a reduction in water solubility with increasing REO concentration from 1 to 3 wt%. The biological assay evidenced the antimicrobial activity of REO-loaded biofilms against Staphylococcus aureus and Escherichia coli. Finally, whole apples were dip-coated with FSM-based solutions to showcase future edible systems. The REO-loaded biofilms extended the shelf life of apples to 30 days, demonstrating their potential for sustainable and active coatings.


Asunto(s)
Antiinfecciosos , Películas Comestibles , Frutas , Semillas , Trigonella , Trigonella/química , Frutas/química , Semillas/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Mucílago de Planta/química , Biopelículas/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Fenómenos Químicos , Solubilidad , Almacenamiento de Alimentos , Antibacterianos/farmacología , Antibacterianos/química , Pruebas de Sensibilidad Microbiana
5.
Polymers (Basel) ; 15(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37447520

RESUMEN

Alginate-based hydrogels are promising smart materials widely employed in the food, bioengineering, and energy sectors. The development and optimization of their production require a thorough knowledge of gelation. In recent years, advanced experimental procedures have been developed for real-time cross-linking alginate reaction monitoring. Novel methods, such as customized rheometric setups, enable the recording of mechanical properties and morphological changes during hydrogel formation. These innovative techniques provide important insights into the gelation stages, the reaction rate, the diffusion of cross-linker to polymer chains, and the homogeneity of the gelling structures. Based on real-time experimental data, kinetic models are developed to enhance comprehension of the reaction mechanism and, eventually, to predict the gelation progress. The aim is to enable better control of the characterization of both the complex gelation and the propagated structures. This review aspires to present a comprehensive overview and evaluation of the breakthrough innovations of the real-time in situ recording of cross-linking alginate hydrogels and bead formation. A detailed analysis of the pioneering experimental developments provides a deep comprehension of the alginate gelation, including the parameters controlling the reaction.

6.
Polymers (Basel) ; 15(6)2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36987338

RESUMEN

Hydrogels are highly versatile and widely applicable materials within various scientific, technological, and food sectors. Alginate and gelatin hydrogels, along with their crafted variations, are possibly the most common ones. However, the ionic crosslinking of alginate-Ca++ is a different gelation mechanism than the physical crosslinking of gelatin. In this work, we prepare alginate-Ca++ hydrogels using individual layer gelation and experimentally evaluate LAOS rheological behavior. We apply shear-stress decomposition using the MITlaos software and obtain the elastic and viscous contributions within the nonlinear response of the individual alginate-Ca++ layer. We compare these results with the nonlinear responses of the gelatin-alginate ex situ individual layer. The strain-sweep patterns are similar, with loss modulus overshoot. The applied shear can destroy the larger-scale structural units (agglomerate/aggregates), resulting in analogous patterns. However, the critical strain points are different. Based on the shear-thickening ratio T of the LAOS analysis, it can be assumed that the common feature of ex situ preparation, i.e., gelation as individual layers, provides a matching bulk microstructure, as the hydrogels differ significantly at a molecular-binding level.

7.
J Biomed Mater Res A ; 111(10): 1588-1599, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37191205

RESUMEN

The study reports on a simple system to fabricate skin substitutes consisting of a naturally occurring bacterial polysaccharide gellan gum. Gelation was driven by the addition of a culture medium whose cations induced gellan gum crosslinking at physiological temperature, resulting in hydrogels. Human dermal fibroblasts were incorporated in these hydrogels and their mechanical, morphological, and penetration characteristics were studied. The mechanical properties were determined by means of oscillatory shear rheology, and a short linear viscoelastic regime was noted up to less than 1% of strain amplitude. The storage modulus increased with an increasing polymer concentration. The moduli were in the range noted for native human skin. After 2 weeks of fibroblast cultivation, the storage moduli showed signs of deterioration, so that a culture time of 2 weeks was proposed for further studies. Microscopic and fluorescent staining observations were documented. These depicted a crosslinked network structure in the hydrogels with a homogeneous distribution of cells and an assured cell viability of 2 weeks. H&E staining was also performed, which showed some traces of ECM formation in a few sections. Finally, caffeine penetration experiments were carried out with Franz diffusion cells. The hydrogels with a higher concentration of polymer containing cells showed an improved barrier function against caffeine compared to previously studied multicomponent hydrogels as well as commercially available 3D skin models. Therefore, these hydrogels displayed both mechanical and penetration compatibility with the ex vivo native human skin.


Asunto(s)
Piel Artificial , Piel , Humanos , Masculino , Adulto Joven , Células Cultivadas , Hidrogeles/química , Viscosidad , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Supervivencia Celular
8.
Sci Rep ; 12(1): 3226, 2022 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-35217700

RESUMEN

In the current study, droplets dynamics under an asymmetric electric field in a T-junction are numerically studied using COMSOL Multi-physics software. The effect of different factors such as dimensionless length of mother droplet (L*), Capillary number (Ca), and electric capillary number (Cae) are investigated on the breakup process in symmetric T-junctions. Two novel patterns of droplets, namely, hybrid asymmetric splitting mode and sorting patterns, have been observed by imposing an electric field in one branch of the microchannel. It is also concluded that using an electric field is a promising strategy to reach droplets with arbitrary sizes and control over the splitting ratio of daughter droplets precisely in a T- junction by adjusting the electric field strength. After a certain electric capillary number ([Formula: see text]), the mother droplet does not breakup and is sorted on the side of the branch that the electric field imposes. Furthermore, [Formula: see text] increases with the increment of L* and Ca.


Asunto(s)
Electricidad
9.
Polymers (Basel) ; 14(12)2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35745971

RESUMEN

Edible polymers such as polysaccharides, proteins, and lipids are biodegradable and biocompatible materials applied as a thin layer to the surface of food or inside the package. They enhance food quality by prolonging its shelf-life and avoiding the deterioration phenomena caused by oxidation, humidity, and microbial activity. In order to improve the biopolymer performance, antimicrobial agents and plasticizers are also included in the formulation of the main compounds utilized for edible coating packages. Secondary natural compounds (SC) are molecules not essential for growth produced by some plants, fungi, and microorganisms. SC derived from plants and fungi have attracted much attention in the food packaging industry because of their natural antimicrobial and antioxidant activities and their effect on the biofilm's mechanical properties. The antimicrobial and antioxidant activities inhibit pathogenic microorganism growth and protect food from oxidation. Furthermore, based on the biopolymer and SC used in the formulation, their specific mass ratio, the peculiar physical interaction occurring between their functional groups, and the experimental procedure adopted for edible coating preparation, the final properties as mechanical resistance and gas barrier properties can be opportunely modulated. This review summarizes the investigations on the antimicrobial, mechanical, and barrier properties of the secondary natural compounds employed in edible biopolymer-based systems used for food packaging materials.

10.
Eng Life Sci ; 22(11): 681-698, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36348656

RESUMEN

Techniques for tissue culture have seen significant advances during the last decades and novel 3D cell culture systems have become available. To control their high complexity, experimental techniques and their Digital Twins (modelling and computational tools) are combined to link different variables to process conditions and critical process parameters. This allows a rapid evaluation of the expected product quality. However, the use of mathematical simulation and Digital Twins is critically dependent on the precise description of the problem and correct input parameters. Errors here can lead to dramatically wrong conclusions. The intention of this review is to provide an overview of the state-of-the-art and remaining challenges with respect to generating input values for computational analysis of mass and momentum transport processes within tissue cultures. It gives an overview on relevant aspects of transport processes in tissue cultures as well as modelling and computational tools to tackle these problems. Further focus is on techniques used for the determination of cell-specific parameters and characterization of culture systems, including sensors for on-line determination of relevant parameters. In conclusion, tissue culture techniques are well-established, and modelling tools are technically mature. New sensor technologies are on the way, especially for organ chips. The greatest remaining challenge seems to be the proper addressing and handling of input parameters required for mathematical models. Following Good Modelling Practice approaches when setting up and validating computational models is, therefore, essential to get to better estimations of the interesting complex processes inside organotypic tissue cultures in the future.

11.
Galen Med J ; 9: e1906, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-34466610

RESUMEN

BACKGROUND: Infections are a major concern in fixation surgeries. Most of the infections could occur in the first three months after the operation. CASE REPORT: We present a 45-year-old man who known case of achondroplasia who underwent craniospinal fixation and was presented to our clinic with surgical site infection after six years. His instruments were removed, and a halo vest was fixed for the patients. Accordingly, he received intravenous antibiotics, and during nine months' follow-up, no any significant problems were found. CONCLUSION: Infection of instruments in spinal surgeries might be presented years after the surgery. Hence, it needs to be considered by surgeons in patients' follow-ups.

12.
Clin Neurol Neurosurg ; 173: 77-83, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30092407

RESUMEN

OBJECTIVES: As the important role of inflammation in pathophysiology of intervertebral disc degeneration and inconsistency regarding the role of pro-inflammatory cytokine genes SNPs, the current case-control study was designed to assess this in Iranian population. PATIENTS AND METHODS: The genomic DNA of peripheral leukocytes of 76 patients and 140 healthy controls were investigated to sequence 9 SNPs of pro-inflammatory cytokine genes of interleukin 1 (IL-1), interleukin 6 (IL-6), and Tumor Necrosis Factor α (TNF-α) family. RESULTS: 'GA' and 'GG' genotype of TNF-α -308 G/A SNP were significantly associated with IVDD. While 'GA' was 1.93 times more frequent in patients, the 'GG' genotype was more common among healthy subjects (OR = 0.51, P = 0.03). The 'G' allele of TNF-α -238 G/A was 2.51 times more common in IVDD patients while the 'A' genotype was more frequent in controls with odds ratio of 0.39 (P = 0.001). Interestingly, the homozygote 'GG' genotype was 2.98 times more prevalent in patients (P = 0.001) while the 'GA' heterozygote genotype was more common in healthy individuals (OR = 0.34). The other investigated SNPs were not significantly associated with disease in this study population. CONCLUSION: Polymorphisms of pro-inflammatory cytokine genes could take part in IVDD pathophysiology as the result of alteration in their expression levels or structures. The current study indicated significant roles of TNF-α -308 G/A and TNF-α -238 G/A SNPs with IVDD among Iranian patients. However, this study did not show any significant association between IVDD and either of SNPs of IL-1 and IL-6 genes.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Degeneración del Disco Intervertebral/genética , Polimorfismo de Nucleótido Simple/genética , Factor de Necrosis Tumoral alfa/genética , Adulto , Estudios de Casos y Controles , Citocinas/genética , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Humanos , Interleucina-10/genética , Interleucina-6/genética , Degeneración del Disco Intervertebral/patología , Irán , Masculino
13.
Int J Med Robot ; 13(4)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27917580

RESUMEN

BACKGROUND: Finite element models for estimation of intraoperative brain shift suffer from huge computational cost. In these models, image registration and finite element analysis are two time-consuming processes. METHODS: The proposed method is an improved version of our previously developed Finite Element Drift (FED) registration algorithm. In this work the registration process is combined with the finite element analysis. In the Combined FED (CFED), the deformation of whole brain mesh is iteratively calculated by geometrical extension of a local load vector which is computed by FED. RESULTS: While the processing time of the FED-based method including registration and finite element analysis was about 70 s, the computation time of the CFED was about 3.2 s. The computational cost of CFED is almost 50% less than similar state of the art brain shift estimators based on finite element models. CONCLUSIONS: The proposed combination of registration and structural analysis can make the calculation of brain deformation much faster.


Asunto(s)
Encéfalo/patología , Análisis de Elementos Finitos , Fantasmas de Imagen , Algoritmos , Animales , Simulación por Computador , Perros , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Modelos Animales , Modelos Teóricos , Reproducibilidad de los Resultados , Programas Informáticos , Factores de Tiempo
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