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1.
Int Wound J ; 21(4): e14571, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38111169

RESUMO

Platelet-rich fibrin (PRF), which is the rich source of growth factors, has been used as an efficient scaffold in tissue engineering and wound healing. In this study, tannic acid as a green cross-linker with different concentrations (0.5%, 1%, 5% and 10%) was used to improve the properties of PRF. The cross-linked gel scaffolds were evaluated by analyses such as scanning electron microscopy, Fourier transform infrared spectroscopy, swelling and degradation, mechanical strength, cell toxicity, cell adhesion and antibacterial test. The results showed that the scaffold structure changes by increasing cross-linker concentration. The swelling rate decreased from 49% to 5% for the samples without the cross-linker and with tannic acid (10%), respectively. The degradation percentage for the cross-linked samples was 8%, which showed a lower degradation rate than the non-cross-linked samples (63%). The mechanical strength of the scaffold with the cross-linker increased up to three times (Young's modulus for the non-cross linked and the cross-linked samples: 0.01 and 0.6 MPa, respectively). Cytotoxicity was not observed up to 10% cross-linker concentration. The cells proliferated well on the cross-linked scaffolds and also showed a good antibacterial effect. In general, tannic acid can improve the physical and mechanical properties of PRF without negatively affecting its biological properties.


Assuntos
Fibrina Rica em Plaquetas , Polifenóis , Alicerces Teciduais , Humanos , Alicerces Teciduais/química , Fibrina Rica em Plaquetas/metabolismo , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
2.
Cell Biochem Funct ; 41(4): 434-449, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37017290

RESUMO

Despite significant advancements in tissue engineering and regenerative medicine during the last two decades, the fabrication of proper scaffolds with appropriate cells can still be considered a critical achievement in this field. Hypoxia is a major stumbling block to chronic wound healing, which restrains tissue engineering plans because a lack of oxygen may cause cell death. This study evaluated the cocultured human keratinocytes and human adipose-derived mesenchymal stem cells (AMSCs) on a multilayer oxygen-releasing electrospun scaffold based on PU/PCL.Sodium percarbonate (SPC)-gelatin/PU. The scaffold was characterized using Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) methods. Flow cytometry confirmed mesenchymal stem cells, and then the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay and DAPI staining were used to assess the in vitro biocompatibility of the scaffold. The experimental results showed that the multilayer electrospun scaffold containing 2.5% SPC could efficiently produce oxygen. Furthermore, according to cell viability results, this structure makes a suitable substrate for the coculture of keratinocytes and AMSCs. Gene expression analysis of various markers such as Involucrin, Cytokeratin 10, and Cytokeratin 14 after 14 days confirmed that keratinocytes and AMSCs coculture on PU/PCL.SPC-gelatin/PU electrospun scaffold promotes dermal differentiation and epithelial proliferation compared to keratinocytes single-cell culture. Therefore, our study supports using oxygen-releasing scaffolds as a potential strategy to hasten skin tissue regeneration. Based on the results, this structure is suggested as a promising candidate for cell-based skin tissue engineering. Given that the developed oxygen-generating polymeric electrospun scaffolds could be used as part of a future strategy for skin tissue engineering, the PU/PCL.SPC-gelatin/PU hybrid electrospun multilayer scaffold in combination with keratinocyte/AMSC coculture is proposed as an effective substrate for skin tissue engineering and regenerative medicine platforms.


Assuntos
Células-Tronco Mesenquimais , Alicerces Teciduais , Masculino , Humanos , Técnicas de Cocultura , Alicerces Teciduais/química , Gelatina/metabolismo , Prepúcio do Pênis , Oxigênio/farmacologia , Oxigênio/metabolismo , Queratinócitos/metabolismo , Células-Tronco Mesenquimais/metabolismo
3.
Andrologia ; 54(6): e14402, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35212016

RESUMO

Polyvinylpyrrolidone (PVP) has been utilized in intracytoplasmic sperm injection (ICSI) for immobilization and manipulation of spermatozoa. This study aims to determine the suitable time that sperm cells could be safely exposed to PVP during ICSI procedure. Twenty-five normal semen samples were prepared using the swim-up method and then were exposed to 10% PVP at different time intervals (15, 30 and 60 min). The effect of PVP on sperm parameters (viability and morphology), DNA fragmentation index (sperm chromatin dispersion test), chromatin quality (aniline blue, toluidine blue and chromomycin A3 staining), acrosome reaction, mitochondrial membrane potential and sperm ultrastructure was assessed at different time intervals. Our results showed that prolonged sperm exposure in PVP for 15, 30 and 60 min significantly affects viability and morphology with a concomitant increase in DNA fragmentation and abnormal chromatin structure, while the percentage of acrosome-reacted spermatozoa was additionally increased. In addition, the spermatozoa with high mitochondrial membrane potential were significantly decreased compared to unexposed spermatozoa to PVP. In conclusion, the detrimental effects of PVP were increased significantly following sperm exposure in PVP after 15 min. Therefore, the sperm exposure to PVP should be limited to less than 15 min during ICSI procedure.


Assuntos
Povidona , Espermatozoides , Reação Acrossômica , Cromatina , Fragmentação do DNA , Humanos , Masculino , Povidona/toxicidade , Motilidade dos Espermatozoides
4.
Cryobiology ; 104: 15-22, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34822804

RESUMO

Testicular sperm extraction (TESE) is an invasive surgery for achieving the spermatozoa in cases with azoospermia. In these patients, the number of retrieved spermatozoa is limited and the optimal cryo-storage is very critical for their fertility preservation. Therefore, single sperm vitrification has been introduced for preservation of low number of spermatozoa. The goal was to assess the efficacy of sperm freezing medium (SFM) and sucrose medium as cryoprotectants for single sperm vitrification in cases with severe oligozoospermia and azoospermia. A total of 20 ejaculates from severe oligozoospermia and 20 testicular samples from azoospermia were processed. Twenty-five sperm cells were collected using ICSI injection pipette and transferred to a cryoprotectant droplet placed on the Cryotech, then vitrified by plunging in liquid nitrogen. Sperm motility, viability, fine-morphology, mitochondrial activity and DNA fragmentation index (DFI) were assessed before and after vitrification. Sperm motility, viability and the percentage of cells with mitochondrial activity were significantly decreased after vitrification in both severe oligozoospermic and testicular samples in either cryoprotectants. However, the rates of post-warm sperm motility and the cells with mitochondrial activity increased significantly in sucrose medium in both severe oligozoospermic and testicular samples compared to SFM. In testicular samples, the DFI of spermatozoa vitrified in SFM was significantly higher than those vitrified with sucrose medium. Sperm motility, viability, mitochondrial activity, and DNA integrity were better preserved in sucrose medium than SFM after single cell vitrification. The presented method may be a useful candidate for successful freezing of individual sperm cells in clinical setting.


Assuntos
Azoospermia , Oligospermia , Preservação do Sêmen , Criopreservação/métodos , Crioprotetores/farmacologia , Meios de Cultura , Humanos , Masculino , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides , Sacarose/farmacologia , Vitrificação
5.
Andrologia ; 52(9): e13702, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32524668

RESUMO

Erythrocyte lysing buffer (ELB) facilitates the search for spermatozoa by eliminating erythrocytes in testicular suspension used during the ICSI procedure. This study investigates the effects of ELB on sperm quality parameters, sperm chromatin and sperm DNA fragmentation. Normal ejaculations were used as the model for testicular spermatozoa in this study. After swim-up, the sperm pellets were divided into two parts. Part I, the control (Group A), was diluted with culture media; and Part II, the intervention group (Group B), was diluted with ELB for 10 min. After centrifugation in both groups, the sperm pellets were re-suspended with culture media. The samples were immediately evaluated (A0 and B0) and then evaluated again after 1 hr (A1 and B1). The results indicated ELB decreased the progressive motility (81.60 ± 8.69 vs. 64.69 ± 19.08) and viability (97.62 ± 3.02 vs. 85.91 ± 11.46), in Group A and B, respectively, both immediately and 1 hr after preparation. Also, ELB engendered a significant increase in the DNA fragmentation index both immediately (9.68 ± 3.55 vs. 14.38 ± 6.52) and after 1 hr (10.37 ± 5.03 vs. 19.38 ± 6.39). In conclusion, ELB may damage sperm cells, shown by a decreased motility and viability, and it increased DNA fragmentation. Therefore, the use of ELB in testicular semen handling should be discouraged.


Assuntos
Motilidade dos Espermatozoides , Espermatozoides , Cromatina , Fragmentação do DNA , Eritrócitos , Humanos , Masculino , Análise do Sêmen
6.
J Biomed Mater Res A ; 108(8): 1747-1759, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32270582

RESUMO

Polymers and scaffolds are the most significant tools in regenerative medicine. Urogenital disorders are an important group of diseases that greatly affect the patient's life expectancy and quality. Reconstruction of urogenital defects is one of the current challenges in regenerative medicine. Regenerative medicine, as well as tissue engineering, may offer suitable approaches, while the tools needed are appropriate materials and cells. Autologous urothelial cells obtained from biopsy, bone marrow-derived stem cells, adipose stem cells and urine-derived stem cells that expressed mesenchymal cell markers are the cells that mainly used. In addition, two main types of biomaterials mainly exist; synthetic polymers and composite scaffolds that are biodegradable polymers with controllable properties and naturally derived biomaterials such as extracellular matrix components and acellular tissue matrices. In this review, we present and evaluate the most appropriate and suitable scaffolds (naturally derived and synthetic polymers) and cells applied in urogenital reconstruction.


Assuntos
Doenças Urogenitais Femininas/terapia , Doenças Urogenitais Masculinas/terapia , Medicina Regenerativa , Engenharia Tecidual , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Feminino , Humanos , Masculino , Medicina Regenerativa/métodos , Transplante de Células-Tronco , Engenharia Tecidual/métodos , Alicerces Teciduais/química
7.
J Hum Reprod Sci ; 10(2): 138-141, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28904505

RESUMO

In-vitro maturation (IVM) of the immature oocytes recovered from the surgically removed ovarian tissue has been considered as a process for fertility preservation in patients with cancer. Fertility preservation for a woman with Mullerian adenocarcinoma. A 37-year-old woman with Mullerian adenocarcinoma was a candidate for ovarian resection. The immature oocytes were retrieved after ovarian resection from a 37-year-old woman with Mullerian adenocarcinoma. The oocytes underwent IVM and were fertilized using intracytoplasmic sperm injection (ICSI). Two healthy embryos were cryopreserved for future use. The immature oocytes from the ovarian tissue can be matured with IVM for generation of embryos after ICSI. The embryos can be vitrified using routine methods for fertility preservation in young women with cancer.

8.
Clin Exp Reprod Med ; 43(3): 181-4, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27689042

RESUMO

The aim was to report a healthy live birth using re-vitrified-warmed cleavage-stage embryos derived from supernumerary warmed embryos after frozen embryo transfer (ET) in a patient with recurrent implantation failure (RIF). The case was a 39-year-old female with a history of polycystic ovarian syndrome and adenomyosis, along with RIF. After ovarian hyperstimulation, 33 cumulus-oocyte complexes were retrieved and fertilized with conventional in vitro fertilization and intracytoplasmic sperm injection. Because of the risk of ovarian hyperstimulation syndrome, 16 grade B and C embryos were vitrified. After 3 and 6 months, 3 and 4 B-C warmed embryos were transferred to the uterus, respectively. However, implantation did not take place. Ten months later, four embryos were warmed, two grade B 8-cell embryos were transferred, and two embryos were re-vitrified. One year later, the two re-vitrified cleavage-stage embryos were warmed, which resulted in a successful live birth. This finding showed that following first warming, it is feasible to refreeze supernumerary warmed embryos for subsequent ET in patients with a history of RIF.

9.
Med J Islam Repub Iran ; 30: 320, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27390690

RESUMO

BACKGROUND: Visfatin is an adipocytokine secreted by visceral adipose tissue. It has been shown that adipocytokines may contribute to the induction of carcinogens and progression of tumors. Previously, we found a significant increase in the visfatin serum level in colorectal cancer patients. Herein, we investigated if this cytokine increases in patients with colorectal adenoma as a precursor of colorectal cancer. METHODS: In this case-control analytic study, a total of 34 patients diagnosed with colorectal adenoma and 35 disease-free controls were included. Adenomas were also categorized based on their location within the colon. Visfatin serum levels were measured in all cases and controls using enzyme- linked immunosorbent assay kits. In order to compare visfatin levels between groups a twotailed t-test was considered. Pearson correlation was also used to assess the relationship between visfatin levels and other measured variables. RESULTS: Patients included 18 male (53%) and 16 female (47%) with a mean±SD age of 48.3±10.96 years and controls were 18 male (51%) and 17 female (49%) with a mean±SD age of 51.6±12.52 years. There were no significant difference in terms of the visfatin level between the two groups (6.7±3.01 ng/ml for patients and 6.8±2.49 ng/ml for controls, p>0.05). Except for a significant correlation between the BMI and visfatin level (p=0.041), no other correlation was detected. We found no significant difference between the levels of visfatin in each location of adenoma comparing the healthy controls (p>0.05 in all comparisons). There was no statistical difference between the locations groups in terms of visfatin level as well (p>0.05). CONCLUSION: Visfatin serum level does not significantly increase in patients with colorectal adenoma. Site of adenoma within the colon or rectum does not seem to play an important role in this regard as well.

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