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1.
J Cell Physiol ; 234(10): 18942-18950, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30916357

RESUMEN

Proper epigenetic modifications during preimplantation embryo development are important for a successful pregnancy. We aim to investigate the putative influence of in vitro fertilization (IVF) and vitrification on DNA methylation in mouse preimplantation embryos. The study groups consisted of blastocyst-derived vitrified two-cell embryos, nonvitrified embryos, and a control group of in vivo derived blastocysts. We assessed developmental competence, global DNA methylation, relative expression levels of miR-29a/29b, and their target genes, Dnmt3a/3b. Vitrified embryos had a lower developmental rate as compared with nonvitrified embryos. There was no significant decrease in blastocyst cell numbers among studied groups, whereas there was a steady decline in DNA methylation after IVF and vitrification. The levels of miR-29a/29b upregulated in the experimental groups as compared with the control group. IVF and vitrification caused Dnmt3a/3b downregulations in blastocysts. The results of this study have suggested that a relationship exists between IVF and embryo vitrification with methylation interruptions in the blastocysts.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/metabolismo , Metilación de ADN/genética , Fertilización In Vitro , MicroARNs/genética , Vitrificación , Animales , Blastocisto/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , ADN Metiltransferasa 3A , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/fisiología , Epigénesis Genética/genética , Femenino , Masculino , Ratones , MicroARNs/biosíntesis , Embarazo , ADN Metiltransferasa 3B
2.
Cell Biochem Funct ; 35(1): 50-55, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28083964

RESUMEN

There is a positive relation between decreases of triiodothyronine (T3) amounts and severity of stroke. The aim of this study was to evaluate the effect of exogenous T3 application on levels of neurogenesis markers in the subventricular zone. Cerebral ischemia was induced by middle cerebral artery occlusion in male Wistar rats. There were 4 experimental groups: sham, ischemic, vehicle, and treatment. Rats were injected with T3 (25 µg/kg, IV injection) at 24 hours after ischemia. Animals were sacrificed at day 7 after ischemia. There were high levels of brain-derived neurotrophic factor, nestin, and Sox2 expressions in gene and protein levels in the T3 treatment group (P ≤ .05 vs ischemic group). Treatment group showed high levels of sera T3 and thyroxine (T4) but low levels of thyrotropin (TSH), tumor necrosis factor-α, and interleukin-6 (P ≤ .05 vs ischemic group) at day 4 after ischemia induction. Findings of this study revealed the effectiveness of exogenous T3 application in the improvement of neurogenesis possibly via regulation of proinflammatory cytokines.


Asunto(s)
Isquemia Encefálica/patología , Citocinas/metabolismo , Neurogénesis/efectos de los fármacos , Triyodotironina/farmacología , Animales , Western Blotting , Isquemia Encefálica/etiología , Isquemia Encefálica/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/complicaciones , Interleucina-6/sangre , Masculino , Nestina/genética , Nestina/metabolismo , Ratas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre , Factor de Necrosis Tumoral alfa/sangre
3.
Metab Brain Dis ; 32(1): 185-193, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27549229

RESUMEN

Stroke is the consequence of limited blood flow to the brain with no established treatment to reduce the neurological deficits. Focusing on therapeutic protocols in targeting subventricular zone (SVZ) neurogenesis has been investigated recently. This study was designed to evaluate the effects of retinoic acid (RA)-pretreated Wharton's jelly mesenchymal stem cells (WJ-MSCs) in combination with triiodothyronine (T3) in the ischemia stroke model. Male Wistar rats were used to induce focal cerebral ischemia by middle cerebral artery occlusion (MCAO). There were seven groups of six animals: Sham, Ischemic, WJ-MSCs, RA-pretreated WJ-MSCs, T3, WJ-MSCs +T3, and RA-pretreated WJ-MSCs + T3. The treatment was performed at 24 h after ischemia, and animals were sacrificed one week later for assessments of retinoid X receptor ß (RXRß), brain-derived neurotrophic factor (BDNF), Sox2 and nestin in the SVZ. Pro-inflammatory cytokines in sera were measured at days four and seven after ischemia. RXRß, BDNF, Sox2 and nestin had the significant expressions in gene and protein levels in the treatment groups, compared with the ischemic group, which were more vivid in the RA-pretreated WJ-MSCs + T3 (p ≤ 0.05). The same trend was also resulted for the levels of TNF-α and IL-6 at four days after ischemia (p ≤ 0.05). In conclusion, application of RA-pretreated WJ-MSCs + T3 could be beneficial in exerting better neurotrophic function probably via modulation of pro-inflammatory cytokines.


Asunto(s)
Infarto de la Arteria Cerebral Media/terapia , Ventrículos Laterales/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos , Accidente Cerebrovascular/terapia , Tretinoina/uso terapéutico , Triyodotironina/uso terapéutico , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Citocinas/sangre , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/metabolismo , Masculino , Células Madre Mesenquimatosas , Nestina/metabolismo , Ratas , Ratas Wistar , Receptor beta X Retinoide/metabolismo , Factores de Transcripción SOXB1/metabolismo , Accidente Cerebrovascular/metabolismo , Gelatina de Wharton
4.
ScientificWorldJournal ; 2014: 828131, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24696663

RESUMEN

Increasing concentrations of greenhouse gases (GHGs) such as CO2 in the atmosphere is a global warming. Human activities are a major cause of increased CO2 concentration in atmosphere, as in recent decade, two-third of greenhouse effect was caused by human activities. Carbon capture and storage (CCS) is a major strategy that can be used to reduce GHGs emission. There are three methods for CCS: pre-combustion capture, oxy-fuel process, and post-combustion capture. Among them, post-combustion capture is the most important one because it offers flexibility and it can be easily added to the operational units. Various technologies are used for CO2 capture, some of them include: absorption, adsorption, cryogenic distillation, and membrane separation. In this paper, various technologies for post-combustion are compared and the best condition for using each technology is identified.


Asunto(s)
Dióxido de Carbono/aislamiento & purificación , Gases/química , Efecto Invernadero
5.
J Biomed Mater Res B Appl Biomater ; 112(1): e35362, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38247246

RESUMEN

Bifunctional tissue engineering constructs promoting osteogenesis and angiogenesis are essential for bone regeneration. Metal ion-incorporated scaffolds and fibrin encapsulation attract much attention due to low cost, nontoxicity, and tunable control over ion and growth factor release. Herein, we investigated the effect of Cu.nHA/Cs/Gel scaffold and fibrin encapsulation on osteogenic and angiogenic differentiation of Wharton's jelly mesenchymal stem cells (WJMSCs) in vitro and in vivo. Cu-laden scaffolds were synthesized using salt leaching/freeze drying and were characterized using standard techniques. WJMSCs were isolated from the human umbilical cord and characterized. WJMSCs with or without encapsulating in fibrin were seeded onto scaffolds, followed by differentiating into the osteogenic lineage for 7 and 21 days. Osteogenic and angiogenic differentiation were evaluated using real-time polymerase chain reaction, western blot, and Alizarin red staining. Then, scaffolds were implanted into critical-sized calvarial bone defects in rats and histological assessments were performed using hematoxylin/eosin, Masson's trichrome, and CD31 immunohistochemical staining at 4 and 12 weeks. The scaffolds had good physicochemical and biological characteristics suitable for cell attachment and growth. Cu and fibrin increased the expression of ALP, RUNX2, OCN, COLI, VEGF, and HIF1α in differentiated WJMSCs. Implanted scaffolds were also biocompatible and were integrated well with the host tissue. Increased collagen condensation, mineralization, and blood vessel formation were observed in Cu-laden scaffolds. The fibrin-encapsulated groups showed the highest collagen and cell densities, immune cell infiltration, and bone trabeculae. CD31-positive cell population increased with fibrin encapsulation and seeding onto Cu-laden scaffolds. Adding Cu to scaffolds and encapsulating cells in fibrin are promising methods that guide osteogenesis and angiogenesis cellular signaling, leading to better bone regeneration.


Asunto(s)
Cobre , Ingeniería de Tejidos , Humanos , Animales , Ratas , Cobre/farmacología , Regeneración Ósea , Osteogénesis , Colágeno
6.
Metab Brain Dis ; 28(1): 45-52, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23212481

RESUMEN

There is an abundance of evidence showing that repeated use of 3,4-methlylenedioxymethamphetamine (MDMA; ecstasy) is associated with brain dysfunction, memory disturbance, locomotor hyperactivity, and hyperthermia. MDMA is toxic to both the serotonergic neurons and dopaminergic system. Adenosine is an endogenous purine nucleoside with a neuromodulatory function in the central nervous system. Nuclear factor kappa-B (NF-kB) plays a pivotal role in the initiation and perpetuation of an immune response by triggering the expression of major inflammatory mediators such as cytokines, chemokines, and adhesion molecules. Here, we investigated the effects of the A2a adenosine receptor (A2a-R) agonist (CGS) and antagonist (SCH) on NF-kB expression after MDMA administration. Male Sprague-Dawley rats were injected to MDMA (10 mg/kg) followed by intraperitoneal injection of either CGS or SCH (0.03 mg/kg each) to animals. The hippocampi were then removed for western blot and RT- PCR analyses. MDMA significantly elevated NF-kB expression. Our results show that administration of CGS following MDMA significantly elevated the NF-kB expression both at mRNA and protein levels. By contrast, administration of the A2a-R antagonist SCH resulted in a decrease in the NF-kB levels. Taken together, these results indicate that, co-administration of A2a agonist (CGS) can protect against MDMA neurotoxic effects by increasing NF-kB expression levels; suggesting a potential application for protection against the neurotoxic effects observed in MDMA users.


Asunto(s)
Agonistas del Receptor de Adenosina A2/farmacología , Antagonistas del Receptor de Adenosina A2/farmacología , Hipocampo/metabolismo , N-Metil-3,4-metilenodioxianfetamina/toxicidad , FN-kappa B/metabolismo , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Receptor de Adenosina A2A/fisiología
7.
Bioimpacts ; 12(3): 233-246, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35677664

RESUMEN

Introduction: Fabricating composite scaffolds with improved physicochemical properties as artificial microenvironments are of great interest in bone tissue engineering. Given advantageous properties of nano-hydroxyapatite/chitosan/gelatin (nHA/Cs/Gel) scaffolds, the present study aimed to synthesize a modified nHA/Cs/Gel biomimetic scaffold with improved features. Methods: Pure and copper (Cu)-substituted nHA was synthesized using the chemical precipitation method under controlled pH and temperature. Pure and Cu-substituted nHA/Cs/Gel scaffolds were fabricated by salt-leaching/freeze-drying method. Physicochemical characteristics of nanoparticles and scaffolds were explored using XRD, FTIR, FE-SEM/EDX, and ICP. Besides, scaffold mechanical strength, degradation, porosity, swelling, biomineralization, and cytocompatibility were assessed. Results: Pure and Cu-substituted nHA were synthesized and characterized with appropriate Cu substitution and improved physical properties. All scaffolds were highly porous (porosity > 98%) and Cu incorporation reduced porosity from 99.555 ± 0.394% to 98.69 ± 0.80% while enlarged the pore size to more than100 µm. Cu-substitution improved the scaffold mechanical strength and the best result was observed in nHA.Cu5%/Cs/Gel scaffolds by the compressive strength 88.869 ± 19.574 MPa. Furthermore, 3% and 5% Cu-substituted nHA enhanced the scaffold structural stability and supported osteoblast spread, adhesion, survival, mineralization, and proliferation. Moreover, long-term and sustainable Cu release from scaffolds was observed within 28 days. Conclusion: Cu-substituted nHA/Cs/Gel scaffolds mimic the porous structure and mechanical strength of cancellous bone, along with prolonged degradation and Cu release, osteoblast attachment, viability, calcium deposition, and proliferation. Taken together, our results indicate the upgraded properties of nHA.Cu5%/Cs/Gel scaffolds for future applications in bone tissue engineering.

8.
Environ Sci Pollut Res Int ; 29(60): 90820-90834, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35876995

RESUMEN

In this study, a new innovative hybrid membrane/vacuum swing adsorption (VSA) process is developed, modeled, and optimized for removal of CO2 from flue gases. The process benefits from the advantages of membrane simplicity and the high product quality of the adsorption system. The main advantage of this new process is the simultaneous increases of both CO2 purity and its recovery. To achieve this objective, in the first step, a membrane system using PEBAX nano-composite membrane was modeled. In the second step, a VSA system using zeolite 13X was modeled. The adsorption equilibrium was predicted by the Toth isotherm. To increase the modeling accuracy, the mass transfer rate was calculated based on the quasi-second-order model. At the final step, the hybrid membrane/VSA process was modeled. Comparison of the new hybrid membrane/VSA with the stand-alone VSA process shows that the CO2 product concentration was increased by 39% and the recovery was improved by 8%. To study the process limitations and increase the product quality, a sensitivity analysis was performed on vacuum pressure, membrane stage cut, and recycle ratio. Based on the results, decreasing the membrane stage cut to 15% and applying a recycle ratio equal to 2 will increase the product quality with the cost of increasing the equipment size. Finally, to achieve the required purity and recovery specification in industrial applications, the process was optimized using the genetic algorithm. Based on these results, it is possible to produce CO2 with 94.7% purity and 99% recovery and N2 with 99.9% purity and 97.3% recovery by regenerating the adsorbents at 0.01 bar, setting the membrane stage cut equal to 11%, keeping the recycle ratio at 1.89, and adjusting the purge-to-feed ratio to 2%.


Asunto(s)
Dióxido de Carbono
9.
Int J Neurosci ; 119(9): 1346-61, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19922361

RESUMEN

Mitochondrial ATP-sensitive potassium channel opener, diazoxide, is shown to have protective effect on the heart and brain following ischemia-reperfusion-induced injury (IR/II). However, the detailed effect of diazoxide and its antagonist on neuronal death, mitochondrial changes, and apoptosis in cerebral IR/II has not fully studied. IR/II was induced in rats by the 4-vessel occlusion model. Neuronal cell death and mitochondrial changes in CA1-CA4 pyramidal cells of the hippocampus were studied by light and electron microscopy, respectively. Apoptosis was assessed by measuring the amount of protein expressed by Bax and Bcl-2 genes. In light microscopy studies, the number of total and normal cells were increased only following 18 mg/kg of diazoxide. Lower doses (2 and 6 mg/kg) failed to change the cell numbers. All three doses of glibenclamide (1, 5, and 25 mg/kg) decreased the number of total and normal cell populations. In electron microscopy studies, different doses of diazoxide and glibenclamide prevented and aggravated the IR-induced morphological changes, respectively. Western blot analysis showed that diazoxide and glibenclamide inhibited and enhanced Bax protein expression respectively. Regarding Bcl-2 expression, only diazoxide showed a significant enhancement of gene expression. In conclusion, the results show that diazoxide can exhibit neuroprotective effects against IR/II in hippocampal regions, possibly through the opening of mitochondrial ATP-sensitive K(+) channels.


Asunto(s)
Diazóxido/antagonistas & inhibidores , Diazóxido/farmacología , Diuréticos/farmacología , Gliburida/farmacología , Hipocampo/citología , Hipoglucemiantes/farmacología , Fármacos Neuroprotectores , Células Piramidales/efectos de los fármacos , Daño por Reperfusión/prevención & control , Animales , Western Blotting , Muerte Celular/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Genes bcl-2/efectos de los fármacos , Hipocampo/efectos de los fármacos , Canales KATP/agonistas , Masculino , Microscopía Electrónica , Mitocondrias/efectos de los fármacos , Mitocondrias/ultraestructura , Ratas , Ratas Wistar , Daño por Reperfusión/patología , Proteína X Asociada a bcl-2/genética
10.
Environ Sci Pollut Res Int ; 26(30): 31038-31054, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31456151

RESUMEN

In this research, waste tyre rubber was used for activated carbon production with a novel route by modified physo-chemical approach. Potassium hydroxide and carbon dioxide were selected as chemical and physical activating agents, respectively and the process was carried out without carbonization under inert atmospheric conditions. The experiments were designed by applying the central composite design (CCD) as one of the subsets of response surface methodology (RSM). The effects of activation temperature (550-750 °C), activation time (15-75 min), impregnation ratio of KOH/rubber (0.75-3.75) and CO2 flow rate (200-400 mL/min) on production yield and specific surface area of produced activated carbon were studied. Based on the results, the 2FI and quadratic models were selected for production yield and specific surface area, respectively. The activation temperature was the main effective parameter on both responses in this process. The production yield and specific surface area of produced activated carbon at optimized conditions for each model were 47% and 928 m2/g, respectively. BET, XRF, XRD, FT-IR, EDS and FE-SEM analyses were carried out on the optimized sample of specific surface area model in order to investigate the residual salts and morphological porous structures. Based on the surface properties and the presence of sulfur compounds in produced activated carbon, this activated carbon has the ability of eliminating heavy metals such as mercury from industrial waste water.


Asunto(s)
Carbón Orgánico/química , Goma/química , Dióxido de Carbono/química , Carbón Orgánico/síntesis química , Diseño de Equipo , Hidróxidos/química , Microscopía Electrónica de Rastreo , Porosidad , Compuestos de Potasio/química , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Temperatura , Administración de Residuos/instrumentación , Administración de Residuos/métodos , Residuos , Difracción de Rayos X
11.
J Biomed Mater Res A ; 107(6): 1166-1175, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30636089

RESUMEN

Study of cell-biomaterial interaction is a crucial aspect of bone tissue engineering to find a state-of-the-art functional substitute. In present study, the Wharton's jelly mesenchymal stem cells (hWJ-MSCs) behavior on three-dimensional biomimetic nano-hydroxyapatite/chitosan/gelatin (nHA/CS/Gel) scaffolds was investigated. The outcome was assessed by histological, biochemical and morphological tests. Results indicated that hWJ-MSCs attached onto the scaffold surface through membrane filopodia, uniformly spread throughout the contacting surface. It only took 3 days for the seeded cells to appear deep inside the scaffold, reflecting proper hWJ-MSCs adhesion and migration, evidenced by both scanning electron microscope and hematoxilin and eosin assessments. Additionally, the present fabricated nHA/CS/Gel scaffold proved to be non-toxic as it supported cell proliferation measured by 3-(4,5-dimethylthiazoyl-2-yl)-2,5-diphenyltetrazolium bromide assay. Moreover, 3-week culture of hWJ-MSCs on scaffolds, immersed in osteogenic medium, rendered the microenvironment in favor of hWJ-MSCs differentiation into osteoblast cells and extracellular matrix secretion. Finally, osteoblasts were immunologically positive for various osteogenic markers including osteocalcin, osteopontin, osteonectin, and alkaline phosphatase. Present findings indicate that nHA/CS/Gel scaffold appropriately harbored hWJ-MSCs, stimulating their growth, migration, proliferation, and differentiation. hWJ-MSCs-loaded nHA/CS/gel substitute may therefore be considered as a suitable platform for the rising demand in in vivo bone repair studies. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1166-1175, 2019.


Asunto(s)
Antígenos de Diferenciación/biosíntesis , Materiales Biomiméticos , Diferenciación Celular/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Andamios del Tejido/química , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Humanos , Células Madre Mesenquimatosas/citología
12.
Bioresour Technol ; 99(13): 5374-83, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18178431

RESUMEN

In this study, hard shell of apricot stones was selected from agricultural solid wastes to prepare effective and low cost adsorbent for the gold separation from gold-plating wastewater. Different adsorption parameters like adsorbent dose, particle size of activated carbon, pH and agitation speed of mixing on the gold adsorption were studied. The results showed that under the optimum operating conditions, more than 98% of gold was adsorbed onto activated carbon after only 3h. The equilibrium adsorption data were well described by the Freundlich and Langmuir isotherms. Isotherms have been used to obtain thermodynamic parameters. Gold desorption studies were performed with aqueous solution mixture of sodium hydroxide and organic solvents at ambient temperatures. Quantitative recovery of gold ions is possible by this method. As hard shell of apricot stones is a discarded as waste from agricultural and food industries, the prepared activated carbon is expected to be an economical product for gold ion recovery from wastewater.


Asunto(s)
Oro , Residuos Industriales , Prunus , Semillas , Residuos , Adsorción , Agricultura , Calorimetría , Carbono , Entropía , Oro/aislamiento & purificación , Iones , Soluciones , Termodinámica
13.
Neuropeptides ; 70: 16-25, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29907375

RESUMEN

Spinal cord injury (SCI) is a serious and complex medical condition that can happen to anyone. At present, therapy mainly focuses on rehabilitation and pharmacological treatment, such as methylprednisolone (MP). Supra-spinal changes in certain structures, such as the cerebellum, that receive many afferents from the spinal cord might be one reason for unsuccessful therapeutic outcomes. Recently, the expression of FNDC5 was reported in cerebellar Purkinje cells as a possible neuroprotective agent. In the present study, we considered the expression of FNDC5 in Purkinje cells following SCI with and without MP administration in adult rats with SCI. Thirty-five adult male rats were used in this study. The animals were randomly allocated into five groups, including SCI, spinal cord injury with methylprednisolone treatment (SCI + MP), operation sham, control, and operation sham with MP. Induction of SCI was achieved by using special clips to compress the spinal cord at a determined level. After a certain interval time, the animals underwent study for FNDC5 expression, apoptosis by using immunohistochemistry, Western blotting, and TUNEL and Nissl staining. Our results showed a significant decrease in the number of Purkinje cells following SCI. Therapy with MP inhibits apoptosis in irFNDC5 Purkinje cells and restores them. Expression of FNDC5 significantly increased in SCI and decreased following MP therapy. We also showed other cerebellar cells with FNDC5 immunoreactivity in the two other cerebellar layers that were firstly reported. Since irisin is known as a plasma product of FNDC5, we think it might be a plasma marker following therapeutic efforts for SCI; however, it needs further research. In addition, it is possible that changes in FNDC5 expression in Purkinje cells might be related to neurogenesis in the cerebellum with unknown mechanisms.


Asunto(s)
Fibronectinas/metabolismo , Metilprednisolona/farmacología , Fármacos Neuroprotectores/farmacología , Traumatismos de la Médula Espinal/tratamiento farmacológico , Enfermedad Aguda , Animales , Modelos Animales de Enfermedad , Masculino , Células de Purkinje/efectos de los fármacos , Ratas Wistar , Médula Espinal/efectos de los fármacos , Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/metabolismo
14.
J Biomed Mater Res B Appl Biomater ; 106(1): 61-72, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27862947

RESUMEN

Bone regeneration is considered as an unmet clinical need, the aim of this study is to investigate the osteogenic potential of three different mesenchymal stem cells (MSCs) derived from human bone marrow (BM-MSCs), umbilical cord Wharton's jelly (UC-MSCs), and adipose (AD-MSCs) seeded on a recently developed nanocomposite scaffold (bioactive glass/gelatin) implanted in rat animal models with critical size calvarial defects. In this study, after isolation, culture, and characterization, the MSCs were expanded and seeded on the scaffolds for in vitro and in vivo studies. The adhesion, proliferation, and viability of the cells on the scaffolds evaluated in vitro, showed that the scaffolds were biocompatible for further examinations. In order to evaluate the scaffolds in vivo, rat animal models with critical size calvarial defects were randomly categorized in four groups and treated with the scaffolds. The animals were sacrificed at the time points of 4 and 12 weeks of post-implantation, bone healing process were investigated. The histological and immunohistological observations showed (p < 0.01) higher osteogenesis capacity in the group treated with BM-MSCs/scaffolds compared to the other groups. However, the formation of new angiogenesis was evidently higher in the defects filled with UC-MSCs/scaffolds. This preliminary study provides promising data for further clinical trials. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 61-72, 2018.


Asunto(s)
Tejido Adiposo/metabolismo , Células Madre Mesenquimatosas/metabolismo , Nanocompuestos/química , Osteogénesis , Andamios del Tejido/química , Tejido Adiposo/citología , Células de la Médula Ósea , Separación Celular , Femenino , Humanos , Células Madre Mesenquimatosas/citología , Especificidad de Órganos
15.
Basic Clin Neurosci ; 8(4): 317-324, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29158882

RESUMEN

INTRODUCTION: The 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is a popular recreational drug and a major source of substance abuse, which ultimately leads to sensations of well-being, elation and euphoria, moderate derealization/depersonalization, and cognitive disruptions, as well as intense sensory awareness. The mechanisms involved in memory impairment induced by MDMA are not completely understood. METHODS: The current study used 40 Sprague-Dawley rats, weighted 200 to 250 g. Experiments were performed in four groups, each containing 10 rats. The first group of rats was used as the control, treated with dimethyl sulfoxide (DMSO). The second group was treated with MDMA. The third group was treated with MDMA and CGS (the adenosine A2A receptor agonist, 2-[p-(2-carboxyethyl) phenethylamino]-5'-N-ethylcarboxamidoadenosine) (CGS 21680) and the fourth group was treated with MDMA and SCH (the A2A receptor antagonist [7-(2-phenylethyl)-5-amino-2-(2-furyl-) pyrazolo-[4, 3-e]-1, 2, 4 triazolo [1,5-] pyrimidine]) (SCH 58261). The drugs in all groups were administrated intraperitoneally (i.p.) once a day for 7 days. In 5 rats of each group, following perfusion, samples were taken from hippocampi to investigate apoptosis. Accordingly, the samples were stained using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay kit, and studied by light microscopy. In other rats, fresh tissue was also removed to study the expression of bax and bcl-2 by Western blotting technique. RESULTS: It was observed that the coadministration of MDMA with CGS reduced bax expression and prevented apoptosis of hippocampal cells. The coadministration of MDMA and SCH increased bax expression, and also increased the frequency of hippocampal cell apoptosis. CONCLUSION: The results of the current study showed that administration of CGS with MDMA decreased the common side effects associated with MDMA.

16.
Mater Sci Eng C Mater Biol Appl ; 75: 688-698, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28415516

RESUMEN

In this research, the osteoinduction effect of a novel variant of bone morphogenetic protein-7 (BMP-7), delivered through bone marrow mesenchymal stem cells (BM-MSCs) seeded on bioactive glass/gelatin nanocomposite scaffolds, was evaluated in a calvarial critical size defect in rats. After being harvested and characterized in vitro, BM-MSCs were infected by a plasmid vector containing BMP-7 encoding gene enriched with a heparin-binding site (B2BMP-7) to assess its osteogenic effects in vivo. The animals were randomly categorized into three groups receiving the scaffold alone (group I), the scaffold seeded with BM-MSCs (group II), and the scaffold seeded with manipulated BM-MSCs (group III). After 2, 4 and 12 postoperative weeks, the animals were sacrificed and the harvested specimens were analyzed using histological and immunohistochemical staining. The results of in vitro tests (preliminary screening) showed that the synthesized scaffolds were biocompatible constructs supporting cell attachment and expansion. The in vivo results revealed higher osteogenesis in the defects filled with the B2BMP-7 excreting BM-MSCs/scaffolds compared to the other two groups. After 12weeks of implantation, fully mature newly formed bone was detected throughout the damaged site, which indicates a synergistic effect of cells, scaffolds and growth factors in the process of tissue regeneration. Therefore, bioactive glass-containing scaffolds pre-seeded with manipulated BM-MSCs exhibit an effective combination to improve osteogenesis in bone defects, and the approach followed in this work could have a significant impact in the development of novel tissue engineering constructs.


Asunto(s)
Células de la Médula Ósea/metabolismo , Proteína Morfogenética Ósea 7/biosíntesis , Regeneración Ósea , Gelatina/química , Vidrio/química , Células Madre Mesenquimatosas/metabolismo , Andamios del Tejido/química , Animales , Células de la Médula Ósea/citología , Proteína Morfogenética Ósea 7/genética , Células Cultivadas , Ensayo de Materiales , Células Madre Mesenquimatosas/citología , Osteogénesis , Ratas
17.
Iran J Basic Med Sci ; 19(6): 646-52, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27482346

RESUMEN

OBJECTIVES: 3, 4-methylenedioxymethamphetamine (MDMA) one of the methamphetamine derivatives that affect the reproductive system, has not been well understood. Many young people are consumers of drugs such as MDMA that can affect their reproductive capability. Apoptosis is the main mechanism for male infertility. Pentoxifylline (PTX) increases cAMP intracellularly and reduces tumor necrosis factor-α. This study aimed to investigate the protective effect of PTX administration in MDMA-induced apoptosis in testes of male Wistar rats. MATERIALS AND METHODS: Thirty male Wistar rats weighing 250-300 g were randomly divided into five groups: control group (without any intervention), group receiving 7.5 mg/kg MDMA three times every two hours for one day, first experimental group receiving 100 mg/kg PTX just at the time of third injection of MDMA, second experimental group receiving 100 mg/kg PTX a week before MDMA administration, and the vehicle group, which received MDMA+saline. Two weeks later, testes were removed and prepared for H&E staining, TUNEL and Western blot techniques. RESULTS: There was a significant decrease of the score in the MDMA group compared with the control group. In first and second experimental groups, the quality of seminiferous epithelium was improved compared with the MDMA group. The number of TUNEL-positive cells/tubule increased in MDMA and vehicle groups, which is decreased by administration of PTX before MDMA. Expression of active caspase-3 significantly increased in MDMA group, which is significantly decreased by administration of PTX before MDMA. CONCLUSION: PTX can significantly reduce the severity of lesions in the testes following administration of MDMA.

18.
Basic Clin Neurosci ; 7(2): 115-20, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27303606

RESUMEN

INTRODUCTION: Transforming Growth Factor-Beta 1 (TGF-ß1) is a pleiotropic cytokine with potent anti-inflammatory property, which has been considered as an essential risk factor in the inflammatory process of Ischemic Stroke (IS), by involving in the pathophysiological progression of hypertension, atherosclerosis, and lipid metabolisms. -509C/T TGF-ß1 gene polymorphism has been found to be associated with the risk of IS. The aim of this meta-analysis was to provide a relatively comprehensive account of the relation between -509C/T gene polymorphisms of TGF-ß1 and susceptibility to IS. METHODS: Male Wistar rats were divided into sham (receiving phosphate buffered saline within dorsal hippocampus), pilocarpine (epileptic model of TLE), single injection BDNF (epileptic rats which received single high dose of BDBF within dorsal hippocampus), and multiple injections BDNF (epileptic rats which received BDNF in days 10, 11, 12, and 13 after induction of TLE) groups. Their electrocorticogram was recorded and amplitude, frequency, and duration of spikes were evaluated. RESULTS: Amplitude and frequency of epileptiform burst discharges were significantly decreased in animals treated with BDNF compared to pilocarpine group. CONCLUSION: Our findings suggested that BDNF may modulate the epileptic activity in the animal model of TLE. In addition, it may have therapeutic effect for epilepsy. More studies are necessary to clarify the exact mechanisms of BDNF effects.

19.
J Biomed Mater Res A ; 104(7): 1770-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26990815

RESUMEN

The present study used a previously developed three-dimensional Gelatin/Hydroxyapatite (Gel/HA) homogeneous nanocomposite scaffold with porosity of 82% and interconnecting pores ranging from 300 to 500 µm. Cell-seeded scaffolds were used to evaluate bone regeneration of rat critical-size calvarial defect. Totally, 36 male Wistar rats were randomly divided into four experimental groups, including blank defect (defects without any graft), blank scaffold (defects filled with Gel/HA scaffold without cells), and two groups of cell-seeded scaffolds (defects filled with either Gel/HA scaffold seeded with osteoblast-like and endothelial cells or osteoblast-like cell-seeded constructs). After 1, 4, and 12 weeks of scaffold implantation, rats were sacrificed and the calvaria were harvested for histological, immunohistochemical and histomorphometric analysis. In vitro tests showed that scaffolds were nontoxic to cells and promoted ideal cellular attachment. In vivo investigation on scaffold revealed that blank calvarial defects indicated incomplete tissue coverage and little evidence of bone healing. However, blank scaffold and cell-seeded scaffolds significantly promoted osteoconduction and ostegogenesis. Taken together, pre-seeded Gel/HA nanocomposite scaffold with osteoblasts and endothelial cells presented an effective combination to improve osteogenesis in the engineered bone implant. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1770-1778, 2016.


Asunto(s)
Durapatita/farmacología , Gelatina/farmacología , Células Endoteliales de la Vena Umbilical Humana/trasplante , Osteoblastos/trasplante , Cráneo/patología , Andamios del Tejido/química , Cicatrización de Heridas , Animales , Regeneración Ósea/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Inmunohistoquímica , Implantes Experimentales , Masculino , Nanopartículas/química , Nanopartículas/ultraestructura , Osteoblastos/citología , Ratas Wistar , Cráneo/efectos de los fármacos
20.
Mol Neurobiol ; 53(4): 2397-408, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26001761

RESUMEN

Cell transplantation strategies have provided potential therapeutic approaches for treatment of neurodegenerative diseases. Mesenchymal stem cells from Wharton's jelly (WJMSCs) are abundant and available adult stem cells with low immunological incompatibility, which could be considered for cell replacement therapy in the future. However, MSC transplantation without any induction or support material causes poor control of cell viability and differentiation. In this study, we investigated the effect of the nanoscaffolds on WJMSCs differentiation into motor neuronal lineages in the presence of retinoic acid (RA) and sonic hedgehog (Shh). Surface properties of scaffolds have been shown to significantly influence cell behaviors such as adhesion, proliferation, and differentiation. Therefore, polycaprolactone (PCL) nanofibers were constructed via electrospinning, surface modified by plasma treatment, and grafted by collagen. Characterization of the scaffolds by means of ATR-FTIR, contact angel, and Bradford proved grafting of the collagen on the surface of the scaffolds. WJMSCs were seeded on nanofibrous and tissue culture plate (TCP) and viability of WJMSCs were measured by MTT assay and then induced to differentiate into motor neuron-like cells for 15 days. Differentiated cells were evaluated morphologically, and real-time PCR and immunocytochemistry methods were done to evaluate expression of motor neuron-like cell markers in mRNA and protein levels. Our results showed that obtained cells could express motor neuron biomarkers at both RNA and protein levels, but the survival and differentiation of WJMSCs into motor neuron-like cells on the PCL/collagen scaffold were higher than cultured cells in the TCP and PCL groups. Taken together, WJMSCs are an attractive stem cell source for inducing into motor neurons in vitro especially when grown on nanostructural scaffolds and PCL/collagen scaffolds can provide a suitable, three-dimensional situation for neuronal survival and differentiation that suggest their potential application towards nerve regeneration.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Colágeno/farmacología , Células Madre Mesenquimatosas/citología , Neuronas Motoras/citología , Nanofibras/química , Gelatina de Wharton/citología , Adhesión Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Inmunohistoquímica , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Neuronas Motoras/efectos de los fármacos , Nanofibras/ultraestructura , Poliésteres/farmacología , Reacción en Cadena en Tiempo Real de la Polimerasa , Solventes , Espectroscopía Infrarroja por Transformada de Fourier , Andamios del Tejido/química
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