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1.
Int J Biol Macromol ; 230: 123225, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36649874

RESUMEN

Growth differentiation factor 9 (GDF9) is an oocyte-derived protein with fundamental functions in folliculogenesis. While the crucial contributions of GDF9 in follicular survival have been revealed, crystallographic studies of GDF9 structure have not yet been carried out, essentially due to the insoluble expression of GDF9 in E. coli and lack of appropriate source for structural studies. Therefore, in this study, we investigated the impact of different expression rate of bacterial thioredoxin (TrxA) using bicistronic expression constructs to induce the soluble expression of mature human GDF9 (hGDF9) driven by T7 promoter in E. coli. Our findings revealed that in BL21(DE3), the high rate of TrxA co-expression at 30 °C was sufficiently potent for the soluble expression of hGDF9 and reduction of inclusion body formation by 4 fold. We also successfully confirmed the bioactivity of the purified soluble hGDF9 protein by evaluation of follicle-stimulating hormone receptor gene expression in bovine cumulus cells derived from small follicles. This study is the first to present an effective approach for expression of bioactive form of hGDF9 using TrxA co-expression in E. coli, which may unravel the current issues regarding structural analysis of hGDF9 protein and consequently provide a better insight into hGDF9 functions and interactions.


Asunto(s)
Escherichia coli , Factor 9 de Diferenciación de Crecimiento , Humanos , Animales , Bovinos , Escherichia coli/genética , Escherichia coli/metabolismo , Factor 9 de Diferenciación de Crecimiento/genética , Factor 9 de Diferenciación de Crecimiento/metabolismo , Oocitos/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Regiones Promotoras Genéticas/genética
3.
J Chromatogr A ; 1678: 463295, 2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-35878543

RESUMEN

Deterministic lateral displacement (DLD) is a hydrodynamic method known for its high-resolution sorting of particles. It achieves this through a periodic array of obstacles and laminar flow that passively directs particles along in two different directions depending on the particles' diameter. Many prior publications have been dedicated to the structural and geometrical development of DLD arrays to improve separation performance; however, a successful separation requires much more than a well-designed array. This paper shows how separation performance is affected by process parameters. For this purpose, the design and fabrication of a DLD device are described. Then three experiments show how process parameters affect the performance of the device. The first experiment uses dye solutions to visualize the formation of a hydrodynamically focused sample stream. The second experiment shows that the particle separation performance (of 7- & 15-µm particles) is affected by the way output fluids are collected. Finally, the third experiment looks at the particle separation efficiency as the input flow rates and the ratio of buffer to sample are changed. The results show that the proper range for buffer and sample flow rate in this device is 1-10 and 0.1-1 (µl/min), respectively. The buffer to sample flow rate ratio of 10 gives the highest separation efficiency, but at a lower sample throughput. The optimized values are specific for our device but demonstrate processes that we believe are universal for DLD separations.


Asunto(s)
Hidrodinámica , Técnicas Analíticas Microfluídicas , Tamaño de la Partícula
4.
Life Sci ; 291: 120273, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35016877

RESUMEN

AIM: Eye organoids are 3D models of the retina that provide new possibilities for studying retinal development, drug toxicity and the molecular mechanisms of diseases. Although there are several protocols that can be used to generate functional tissues, none have been used to assemble human retinal organoids containing mesenchymal stem cells (MSCs). MAIN METHODS: In this study we intend to assess the effective interactions of MSCs and human embryonic stem cells (hESCs) during retinal organoid formation. We evaluated the inducing activities of bone marrow MSCs (BM-MSCs), trabecular meshwork (TM), and stem cells from apical papilla (SCAP)-derived MSCs in differentiation of hESCs in a three-dimensional (3D) direct co-culture system. KEY FINDINGS: In comparison with the two other MSC sources, the induction potential of SCAP was confirmed in the co-culture system. Although the different SCAP cell ratios did not show any significant morphology changes during the first seven days, increasing the number of SCAPs improved formation of the optic vesicle (OV) structure, which was confirmed by assessment of specific markers. The OVs subsequently developed to an optic cup (OC), which was similar to the in vivo environment. These arrangements expressed MITF in the outer layer and CHX10 in the inner layer. SIGNIFICANCE: We assessed the inducing activity of SCAP during differentiation of hESCs towards a retinal fate in a 3D organoid system. However, future studies be conducted to gather additional details about the development of the eye field, retinal differentiation, and the molecular mechanisms of diseases.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Encía/citología , Retina/citología , Diferenciación Celular/efectos de los fármacos , Línea Celular , Células Cultivadas , Ojo/citología , Encía/metabolismo , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/metabolismo , Humanos , Células Madre Mesenquimatosas/citología , Organoides/citología , Organoides/crecimiento & desarrollo , Organoides/metabolismo , Retina/crecimiento & desarrollo
6.
Acta Biomater ; 126: 238-248, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33771718

RESUMEN

The stem cell-based retinal ganglion cells (RGCs) replacement therapy offers a potential to restore vision in progressive optic neuropathies including glaucoma by replacing degenerated RGCs and by simulating axonal regeneration. Injured optic nerve axons do not regenerate owing to the limited intrinsic capacity of the neurons and the inhibitory environment at the injury site. Polymeric tissue scaffolds are able to modulate the physical environment while providing structural support for transplanted cells, however, their application specific to the RGC generation has been far from conclusive. The successful generation of clinically safe and functional RGCs that can appropriately integrate into the hosts' retinas still remain largely unresolved. Our study reports on a process that enables generation of RGCs from human embryonic stem cells (hESCs) that is simple, straightforward and repeatable and, investigates the influence of the aligned poly(glycerol sebacate) (PGS)/poly(ε-caprolactone) (PCL) scaffold on this differentiation process. Our findings demonstrate that PGS/PCL scaffold promotes differentiation of hESCs into RGC-like cells possibly by the simulation of cell active environmental signalling and, facilitates the growth of RGCs neurites along their lengths. STATEMENT OF SIGNIFICANCE: Glaucoma can lead to the degeneration of retinal ganglion cells (RGCs), with consequential vision loss. RGCs are incapable of self-renewal, replacement of diseased RGCs with healthy cells has been a goal to restore vision in glaucoma patients. In this regard, stem cell RGC replacement therapy has been shown to improve vision in animal models of glaucoma, which could be facilitated by using tissue-engineered polymeric scaffolds. In this study, we generated homogenous stem cell-derived RGCs via a straightforward differentiation protocol and evaluated the effects of PGS/PCL scaffold on RGCs differentiation and growth of RGCs neurites. Our study contributes to the knowledge on how biomaterial scaffolds are able to support the regeneration of RGC neurites (i.e., axons or dendrites) as a part of a possible future clinical therapy for the treatment of glaucoma.


Asunto(s)
Células Madre Embrionarias Humanas , Células Ganglionares de la Retina , Animales , Axones , Diferenciación Celular , Humanos , Nervio Óptico
7.
Mater Sci Eng C Mater Biol Appl ; 120: 111746, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33545888

RESUMEN

There is a great need for tissue engineering constructs with the ability to modulate stem cell behavior. The initial adhesion, growth and differentiation of stem cell are a key strategy in bone tissue engineering and it can be controlled through biomaterial-cell interface. Here we engineered a polycaprolactone/gelatin/bioactive glass (PCL/GT/BG) nanocomposite scaffold coated with Fibronectin (FN) as a potential candidate to aid the bone regeneration process by giving cells a temporary template to grow into. For this purpose, initially BG nanoparticles (nBG) of 70 ± 15 nm were synthesized, characterized and then impregnated into PCL/GT matrix to create a nanocomposite fibrous mesh. An optimized structure was selected based on fiber uniformity, diameter, and the mechanical properties. Cell adhesion, growth, and the expression of osteogenic-related genes as a result of FN tethering, through specific surface interactions, was evaluated. Furthermore, the potential of optimized nanofiberous structure as a drug delivery vehicle for the local release of therapeutic agents was studied by using amoxicillin as a model drug. The release profile revealed that around 70% of drug was released in an hour for non-crosslinked fibers (burst release) followed by a gradual release up to 72 h. The release profile was steadier for crosslinked fibers. The scaffold also showed an antibacterial effect against ubiquitous gram-positive Staphylococcus aureus. The current study provides an insight for future researchers who aim to create nanocomposite materials as multifunctional scaffolds for bone tissue engineering applications.


Asunto(s)
Osteogénesis , Andamios del Tejido , Materiales Biocompatibles , Diferenciación Celular , Ingeniería de Tejidos
8.
Nutr Metab (Lond) ; 18(1): 14, 2021 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-33468193

RESUMEN

BACKGROUND: SPTC is a mix of four herbal components (Salvia officinalis, Panax ginseng, Trigonella foenum-graeceum, and Cinnamomum zeylanicum) which might be prevented the development of AGE rich diet-induced diabetic complication and liver injury through activated the nuclear factor erythroid-2-related-factor-2 (Nrf2) pathway. Nrf2, as a master regulator of antioxidant response elements by activating cytoprotective genes expression, is decreased oxidative stress that associated with hyperglycemia and increases insulin sensitivity. the aim of this study was to assess whether the combination therapy of SPTC along with exercise or metformin moderate oxidative stress related liver injurie with more favorable effects in the treatment of AGE rich diet-induced type 2 diabetic mice. METHODS: We induced diabetes in C57BL/6 mice by AGE using a diet supplementation and limitation of physical activity. After 16 weeks of intervention, AGE fed mice were compared to control mice. Diabetic mice were assigned into seven experimental groups (each group; n = 5): diabetic mice, diabetic mice treated with SPTC (130 mg/kg), diabetic mice treated with Salvia Officinalis (65 mg/kg), diabetic mice treated with metformin (300 mg/kg), diabetic mice with endurance exercise training, diabetic mice treated with SPTC + metformin (130/300 mg/kg), diabetic mice treated with SPTC + exercise training. RESULTS: SPTC + exercise and SPTC + metformin reduced diabetic complications like gain weight, water and calorie intake, blood glucose, insulin, and GLUT4 content more efficiently than each treatment. These combinations improved oxidative stress hemostasis by activating the Nrf2 signaling pathway and attenuating keap1 protein more significantly. CONCLUSION: Eventually, combined treatment of SPTC with exercise or metformin as a novel approach had more beneficial effects to prevent the development of diabetes and oxidative stress associated with hyperglycemia.

9.
J Biomed Mater Res A ; 107(7): 1358-1365, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30724467

RESUMEN

In this study, submicron, monodispersed, spherical bioactive glass (BG) particles with a mean diameter of 720 ± 80 nm were produced through sol-gel process. The prepared BG particles were successfully incorporated into 70/30 (W/W) ratio of polycaprolactone/gelatin (PCL/GT) nanofibrous mats (250 ± 60 nm) through electrospinning to obtain a unique architectural structure for the first time. To enhance biodegradation and stability of the scaffolds, crosslinking using gluteraldehyde was applied. The structure, wettability, hydroxyapatite (HA) formation, cell adhesion, cell viability and osteogenic potential of the fibrous mats were evaluated. A continuous, uniform and hydrophilic structure of PCL/GT/BG was obtained. The fibers were found to be bioactive as they formed HA on their surface after immersion in simulated body fluid. The unique structure significantly reduced HA formation time to 5 days. For in vitro investigations, human dental pulp stem cells (hDPSCs) were cultured on PCL/GT and PCL/GT/BG fibrous mats. Results demonstrated good cell attachment after 4 and 24 h with no significant levels of cytotoxicity during 10 days of culture. Alizarin red staining was applied to quantitatively analyze the potential of PCL/GT/BG in osteogenic differentiation of hDPSCs. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.


Asunto(s)
Materiales Biocompatibles/farmacología , Gelatina/farmacología , Vidrio/química , Nanofibras/química , Tamaño de la Partícula , Poliésteres/farmacología , Células Madre/citología , Animales , Bovinos , Pulpa Dental/citología , Humanos , Nanofibras/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Células Madre/efectos de los fármacos , Células Madre/ultraestructura , Andamios del Tejido/química , Agua/química
10.
J Cell Physiol ; 234(4): 4256-4266, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30191983

RESUMEN

Research that pertains to the molecular mechanisms involved in retinal pigment epithelial (RPE) development can significantly contribute to cell therapy studies. The effects of periocular mesenchymal cells on the expansion of RPE cells remain elusive. We have examined the possible proliferative role of hepatocyte growth factor (HGF) as a mesenchymal cell secretory factor against human embryonic stem cell derived RPE (hESC-RPE). We found that the conditioned medium of human mesenchymal stem cells from apical papilla and/or exogenous HGF promoted proliferation of the hESC-RPE cells as single cells and cell sheets, in addition to rabbit RPE sheets in vitro. Blockage of HGF signaling by HGF receptor inhibitor, PHA-665752, inhibited proliferation of hESC-RPE cells. However, differentiation of hESCs and human-induced pluripotent stem cells to a rostral fate and eye-field specification was unaffected by HGF. Our in vivo analysis showed HGF expression in periocular mesenchymal cells after optic cup formation in chicken embryos. Administration of HGF receptor inhibitor at this developmental stage in chicken embryos led to reduced eye size and disorganization of the RPE sheet. These findings suggested that HGF administration could be beneficial for obtaining higher numbers of hESC-RPE cells in human preclinical and clinical trials.


Asunto(s)
Proliferación Celular , Células Epiteliales/metabolismo , Factor de Crecimiento de Hepatocito/metabolismo , Células Madre Embrionarias Humanas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Comunicación Paracrina , Epitelio Pigmentado de la Retina/metabolismo , Adolescente , Animales , Diferenciación Celular , Embrión de Pollo , Medios de Cultivo Condicionados/metabolismo , Ojo/embriología , Ojo/metabolismo , Humanos , Proteínas Proto-Oncogénicas c-met/metabolismo , Conejos , Vías Secretoras , Transducción de Señal , Adulto Joven
11.
Differentiation ; 101: 8-15, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29574166

RESUMEN

Recently, we have found that human stem cells from apical papilla (SCAP) show a stromal cell-derived inducing activity (SDIA). To examine SDIA competence for retinal cells differentiation, we co-cultured SCAP with human pluripotent stem cells (hPSCs). In comparison with Matrigel-cultured hPSCs, SCAP significantly induces hPSCs to differentiate into rostral neural cells as demonstrated by upregulation of OTX2 and PAX6 and down-regulation of EN1, HOXB4 and HOXC8. Furthermore, the differentiated cells on SCAP significantly expressed eye-field markers, RAX, PAX6, LHX2 and SIX3 and showed five folds pigmented colonies. The generated hPSC-retinal pigmented epithelium (RPE) was hexagonal and highly expressed related markers, ZO-1, RPE65, BEST, CRALBP and MITF. They were able to phagocytose latex beads. Moreover, the assessment of the isolated neural tube-like structures on SCAP showed the expression of retinal progenitor cells (RPCs) - SIX3, RAX, and PAX6. SCAP highly expressed DKK3 and SFRP2, Wnt inhibitor factors and their target genes, Cyclin D1 and c-Myc were down-regulated significantly on SCAP. These results showed SCAP promoted the differentiation of hPSCs into retinal cells (RPE and RPCs) possibly through inhibition of Wnt signaling pathway. This simple and efficient approach provides human RPE generation for developing therapies for diseases such as age-related macular degeneration.


Asunto(s)
Diferenciación Celular/fisiología , Células Madre Embrionarias Humanas/citología , Células Madre Pluripotentes/citología , Retina/citología , Epitelio Pigmentado de la Retina/citología , Técnicas de Cultivo de Célula/métodos , Línea Celular , Células Cultivadas , Humanos
12.
Acta Biomater ; 57: 449-461, 2017 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-28457960

RESUMEN

A challenge in using bioactive melt-derived glass in bone regeneration is to produce scaffolds with interconnected pores while maintaining the amorphous nature of the glass and its associated bioactivity. Here we introduce a method for creating porous melt-derived bioactive glass foam scaffolds with low silica content and report in vitro and preliminary in vivo data. The gel-cast foaming process was adapted, employing temperature controlled gelation of gelatin, rather than the in situ acrylic polymerisation used previously. To form a 3D construct from melt derived glasses, particles must be fused via thermal processing, termed sintering. The original Bioglass® 45S5 composition crystallises upon sintering, altering its bioactivity, due to the temperature difference between the glass transition temperature and the crystallisation onset being small. Here, we optimised and compared scaffolds from three glass compositions, ICIE16, PSrBG and 13-93, which were selected due to their widened sintering windows. Amorphous scaffolds with modal pore interconnect diameters between 100-150µm and porosities of 75% had compressive strengths of 3.4±0.3MPa, 8.4±0.8MPa and 15.3±1.8MPa, for ICIE16, PSrBG and 13-93 respectively. These porosities and compressive strength values are within the range of cancellous bone, and greater than previously reported foamed scaffolds. Dental pulp stem cells attached to the scaffold surfaces during in vitro culture and were viable. In vivo, the scaffolds were found to regenerate bone in a rabbit model according to X-ray micro tomography imaging. STATEMENT OF SIGNIFICANCE: This manuscript describes a new method for making scaffolds from bioactive glasses using highly bioactive glass compositions. The glass compositions have lower silica content that those that have been previously made into amorphous scaffolds and they have been designed to have similar network connectivity to that of the original (and commercially used) 45S5 Bioglass. The aim was to match Bioglass' bioactivity. The scaffolds retain the amorphous nature of bioactive glass while having an open pore structure and compressive strength similar to porous bone (the original 45S5 Bioglass crystallises during sintering, which can cause reduced bioactivity or instability). The new scaffolds showed unexpectedly rapid bone regeneration in a rabbit model.


Asunto(s)
Regeneración Ósea , Cerámica/química , Pulpa Dental/metabolismo , Vidrio/química , Células Madre/metabolismo , Andamios del Tejido/química , Animales , Línea Celular , Pulpa Dental/patología , Femenino , Humanos , Porosidad , Conejos , Células Madre/patología
13.
Reprod Fertil Dev ; 28(6): 723-31, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25482371

RESUMEN

Polycystic ovary syndrome (PCOS) is associated with low-quality oocytes. The aim of the present study was to investigate the effects of metformin (MET), N-acetylcysteine (NAC) and their combination on follicular fluid parameters, oocytes and embryo quality in PCOS patients. A prospective randomised placebo-controlled pilot study on 60 Iranian women with PCOS (aged 25-35 years) undergoing intracytoplasmic sperm injection (ICSI) was designed. Women were divided into four groups (n=15 in each): (1) an MET, administered 1500mg day(-1) MET; (2) an NAC group, administered 1800mg day(-1) NAC; (3) an NAC + MET group; and (4) a placebo group. Drugs were administered from the 3rd day of previous cycle until the day of oocyte aspiration (6 weeks treatment in total). Data were analysed by one-way ANOVA, with significance set at P<0.05. The number of immature and abnormal oocytes decreased significantly in the NAC compared with placebo group, with a concomitant increase in the number of good-quality embryos in the NAC group (P<0.05). Malondialdehyde levels decreased significantly in the NAC and NAC + MET groups compared with the placebo-treated group (P<0.02). In addition, there were significant decreases in leptin levels in the NAC, MET and NAC + MET groups compared with the placebo group (P<0.001). Insulin and LH levels were significantly lower in the MET and NAC groups compared with the placebo-treated group (P<0.02). We concluded that NAC improves oocyte and embryo quality and could be administered as an alternative to MET.


Asunto(s)
Acetilcisteína/uso terapéutico , Antioxidantes/uso terapéutico , Ectogénesis/efectos de los fármacos , Infertilidad Femenina/prevención & control , Oogénesis/efectos de los fármacos , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Inyecciones de Esperma Intracitoplasmáticas , Centros Médicos Académicos , Acetilcisteína/efectos adversos , Adulto , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/uso terapéutico , Antioxidantes/efectos adversos , Quimioterapia Combinada , Femenino , Líquido Folicular/efectos de los fármacos , Humanos , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Infertilidad Femenina/etiología , Irán , Metformina/efectos adversos , Metformina/uso terapéutico , Recuperación del Oocito , Oocitos/efectos de los fármacos , Oocitos/patología , Inducción de la Ovulación , Pacientes Desistentes del Tratamiento , Proyectos Piloto , Síndrome del Ovario Poliquístico/fisiopatología
14.
Theriogenology ; 83(8): 1321-7, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25698161

RESUMEN

Manganese(III) meso-tetrakis(N-ethylpyridinium-2-yl)porphyrin chloride (MnTE) is a cell-permeable superoxide dismutase mimetic agent which can convert superoxide to hydrogen peroxide (H2O2). Supplementation of MnTE to a commercial semen extender can protect sperm from superoxide but not H2O2. Therefore, we proposed that addition of catalase (0.0, 200, or 400 IU/mL) in combination with MnTE (0.1 µM) may further improve the cryopreservation efficiency of goat semen in commercially optimized freezing media such as Andromed. Therefore, ejaculates were obtained from three adult bucks twice a week during the breeding season and diluted with Andromed supplemented with or without MnTE and catalase and were frozen in liquid nitrogen. Sperm parameters and reactive oxygen species contents were evaluated 2 hours after dilution (before freezing) and after freezing/thawing. The results revealed that all the treatments significantly (P ≤ 0.05) improved sperm motility, viability, and membrane integrity after freezing and reduced reactive oxygen species content compared with the control group, but maximum improvement was obtained in MnTE + 400 IU/mL catalase. In addition, supplementation with these antioxidants significantly (P ≤ 0.05) increases the cleavage rate after IVF. In conclusion, the results of present study suggest that addition of antioxidant MnTE or catalase to commercial optimized media, such as Andromed, improves total motility, membrane integrity, and viability of goat semen samples after thawing. But the degree of improvement for these parameters significantly (P ≤ 0.05) higher when MnTE and catalase were simultaneously added to the cryopreservation media.


Asunto(s)
Catalasa/farmacología , Cabras , Metaloporfirinas/farmacología , Análisis de Semen/veterinaria , Semen/fisiología , Superóxido Dismutasa , Animales , Antioxidantes/farmacología , Criopreservación/métodos , Criopreservación/veterinaria , Crioprotectores , Técnicas de Cultivo de Embriones , Femenino , Fertilización In Vitro/veterinaria , Calor , Peróxido de Hidrógeno/metabolismo , Masculino , Especies Reactivas de Oxígeno/análisis , Preservación de Semen/métodos , Preservación de Semen/veterinaria , Motilidad Espermática , Superóxidos/metabolismo
15.
J Pharm Pharm Sci ; 17(4): 461-74, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25579429

RESUMEN

PURPOSE: The aim of this study was to investigate the in vitro gene delivery efficiency of poly[N-(2-aminoethyl)ethylene-imine](PAEEI), a polymer with a linear Polyethyleneimine (LPEI) backbone and with aminoethyl side groups that has two protonatable nitrogen atoms per monomer unit instead of one as in LPEI (an established gene delivery polymer). Method. PAEEI (Mn=4.5 kDa, Mw= 10 kDa) was synthesized by ring-opening polymerization of N-(2-(1'-aziridino)ethyl)formamide followed by hydrolysis of the amide groups. The buffering capacity of the resulting polymer was determined by acid-base titration and consequently the percentage of the protonated nitrogen atoms was calculated. Polyplexes were prepared separately in buffers with different ionic strength including Hepes buffered saline (150 mM NaCl) and Hepes buffered glucose (5% glucose) and their zeta-potential, hydrodynamic diameter and colloidal stability were measured. Transfection activity (and toxicity in Hela cells) of the polyplexes were done in HeLa, CHO and HEK293T cells. Cell incubations with polyplexes were done both in the presence and absence (HeLa cells) of serum. Results. PAEEEI showed two times more buffering capacity than LPEI. PAEEI-based Polyplexes had about the same size and zeta-potential as those of LPEI, with a higher colloidal stability in saline buffer in continuous particle size measurement. Their transfection activity was slightly higher than 22-kDa LPEI polyplexes whereas their toxicity profiles were similar in cell lines studied. The PAEEI polyplexes showed gene expression activity both in the presence and absence of serum. Conclusion. Paying attention to the fact that LPEI molecules with smaller sizes than 22 kDa show less transfection efficiency than LPEI 22, the effect of smaller size of PAEEI (10 kDa) on the gene delivery efficiency was compensated by its higher buffering capacity due to carrying more protonatable nitrogen per monomeric unit comparing with LPEI (22 kDa). Having slightly higher transfection efficiency and better colloidal stability than PEI-based systems, PAEEI is an attractive candidate for future in vivo gene delivery studies.


Asunto(s)
Técnicas de Transferencia de Gen , Polietileneimina/química , Polímeros/química , Transfección , Animales , Células CHO , Cricetinae , Cricetulus , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Células HeLa , Humanos , Nitrógeno/química , Tamaño de la Partícula , Polietileneimina/toxicidad , Polímeros/toxicidad
16.
Avicenna J Med Biotechnol ; 5(1): 2-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23626871

RESUMEN

BACKGROUND: The transcription factor Oct-4, is an important marker of undifferentiating level and a key regulating factor for maintenance of pluripotency in cells. Establishment of an Oct-4 promoter-based reporter system is an appropriate tool for monitoring the differentiation of embryonic stem cells both in vivo and in vitro. METHODS: In the present study, we report construction of a recombinant vector, pDB2 Oct4 promoter/EGFP, in which expression of Enhanced Green Fluorescent Protein (EGFP) was controlled by the mouse Oct-4 promoter. RESULTS: In transfected mouse embryonic stem cells with this vector, EGFP was predicted to be specifically expressed in pluripotency state. After transfection, high-level expression of EGFP under the control of Oct-4 promoter was observed in manipulated embryonic stem cells. CONCLUSION: Thus, our new cellular reporter showed that both the properties of embryonic cells and expression the EGFP could be of great help in studying the differentiating and reprogramming mechanisms of mESCs.

17.
ARYA Atheroscler ; 7(4): 162-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23205050

RESUMEN

BACKGROUND: Myocardial infarction (MI) is an irreversible cardiomyocytes injury which begins after 15-20 minutes of coronary artery occlusion. The extent of infarction is modulated by a number of factors including collateral blood supplies, medications, and ischemic preconditioning. Although angioplasty and thrombolytic agents can relieve the cause of the infarction, the time from the occlusion onset to reperfusion determines the degree of irreversible myocardial injury. Experimental studies suggested that stem cells and progenitor cells derived from bone marrow can be used in the repair of cardiac tissue after acute MI. This study was designed to investigate the feasibility, safety and initial clinical outcome of intracoronary infusion of autologous progenitor cells in patients with acute MI. METHODS: Patients with a history of anterior MI and a left ventricular ejection fraction (LVEF) less than 35 % who were candidates for coronary angioplasty were randomly allocated in a 1:1 ratio to either control or bone marrow cell groups (each including 16 patients). Thallium scan and 17-segment echocardiography analysis for regional wall motion abnormality were performed before and 1 and 6 months after intracoronary infusion of bone marrow cells. The same tests were also conducted for the control group at identical time intervals. Quantitative variables were compared by independent t-test and paired t-test. Statistical significance was assumed at a value of P < 0.05. RESULTS: LVEF in the case and control groups increased to 39.37 ± 2.47% and 31.00 ± 1.87%, respectively (P = 0.069 and 0.1, respectively). Wall motion abnormality index (WMAI) decreased insignificantly in both groups. Perfusion defect scores (PDSs) decreased significantly in the case group. CONCLUSION: In this study, autologous mesenchymal stem cell transplantation by intracoronary catheter during angioplasty in patients with a history of severe LV dysfunction caused mild increases in LVEF.

18.
Avicenna J Med Biotechnol ; 4(4): 206-9, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23408119

RESUMEN

BACKGROUND: Recently, we have shown that peroxisomal protein expression was induced upon retinoic acid treatment in mouse embryonic stem cells during the process of neurogenesis. Thus, characterization of the respective promoter could elucidate the molecular aspects of transcriptional regulation of this gene. METHODS: Using the conventional software programs for promoter prediction, a putative promoter region was identified approximately 561 bp upstream of the peroxisomal protein coding sequence. In order to clone this region with a GC-content of 71.01%, a cocktail of ammonium sulfate buffer supplied with two additive components, betaine and dimethyl sulfoxide, and a high concentration of MgCl(2) was used. RESULTS: The modulated polymerase chain reaction composition significantly improved the amplification of GC-rich DNA target sequences. Improved amplification of this region was due to reduction in the formation of secondary structures by the GC-rich region. CONCLUSION: Therefore, this polymerase chain reaction composition could be generally used to facilitate the amplification of other GC-rich DNA sequences as verified by amplification of different GC rich regions.

19.
Mol Reprod Dev ; 77(10): 868-75, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20737474

RESUMEN

In relation to the growing recent interest in the establishment of sperm-mediated gene transfer (SMGT) technology as a convenient and effective method for the simple production of transgenic animals, in this study the possibility of using SMGT to produce transgenic caprine embryos was investigated for the first time. Buck sperm were directly incubated with different concentrations (0-500 ng) of pcDNA/his/Lac-Z plasmid and used for IVF or ICSI. Sperm used for ICSI were categorized into motile or live-immotile group before being injected into oocytes. In a separate experiment, dead sperm prepared by repeated freezing/thawing were used for DNA-incubation before ICSI. Sham injection was carried out by intracytoplasmic injection of approximately the same volume of media containing different doses of DNA using an ICSI needle. Transgene expression and transmission were detected by X-Gal staining and PCR analysis of developed embryos, respectively. A reasonable blastocyst rate was observed in all the groups. Only embryos in the sham group were negative for transgene transmission. Transgene expression was completely dependent on the delivery technique and status of sperm, and was only observed in the live-immotile and dead ICSI groups. The results of this study showed that the technique (IVF vs. ICSI vs. sham injection), sperm status (motile vs. live-immotile vs. dead) and to some extent DNA concentration affect embryo development, transgene transmission and expression.


Asunto(s)
ADN , Técnicas de Transferencia de Gen , Cabras/embriología , Inyecciones de Esperma Intracitoplasmáticas/métodos , Espermatozoides , Análisis de Varianza , Animales , ADN/administración & dosificación , ADN/metabolismo , Relación Dosis-Respuesta a Droga , Embrión de Mamíferos/metabolismo , Femenino , Modelos Logísticos , Masculino , Oocitos/metabolismo , Reacción en Cadena de la Polimerasa , Espermatozoides/química , Espermatozoides/fisiología
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