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1.
MycoKeys ; 106: 251-264, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974462

RESUMEN

Two novel species within the family Dictyosporiaceae are described and illustrated from terrestrial habitats on dead culms of bamboo and an unidentified plant, respectively. Through morphological comparisons and the multi-locus phylogenetic analyses of combined LSU, ITS, SSU, and tef1-α sequence dataset, two species, Gregaritheciumbambusicola, Pseudocoleophomaparaphysoidea are identified. Phylogenetically, both species clustered into a monophyletic clade with strong bootstrap support. Gregaritheciumbambusicola sp. nov. can be distinguished from other species within the genus based on its almost straight ascospores. Pseudocoleophomaparaphysoidea sp. nov. differs from other species in its conidiogenous cells intermixed with paraphyses, longer conidiogenous cells and larger conidia. The identification of this lineage contributes to our understanding of the classification of Dictyosporiaceae.

2.
Front Bioeng Biotechnol ; 12: 1350227, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38456007

RESUMEN

Fibula transplantation plays an irreplaceable role in restoring the function and morphology of the defected mandible. However, the complex load-bearing environment of the mandible makes it urgent to accurately reconstruct the mandible, ensure the position of the condyle after surgery, and restore the patient's occlusal function and contour. The intervention of digital design and three-dimensional (3D) printed titanium mesh provides a more efficient method and idea to solve this problem. Digital design guides the accurate positioning, osteotomy, and simultaneous implant placement during surgery, and 3D printed titanium mesh ensures stable condyle position after surgery, restoring good mandibular function. The double-layer folded fibula maintains the vertical height of the mandible and a good facial contour, and simultaneous implant placement can establish a good occlusal relationship. This study conducted a retrospective analysis of five patients with jaw defects who underwent digital fibula reconstruction over the past 3 years. It was found that the surgical protocol combining digital design, 3D printed intraoperative guides, 3D printed titanium mesh, free fibula flap, immediate implant, and occlusal reconstruction to repair jaw defects had more ideal facial appearance and biological function. It will provide a more reliable surgical protocol for clinical management of large mandibular defects.

3.
Front Bioeng Biotechnol ; 12: 1343294, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38333080

RESUMEN

Polyetheretherketone (PEEK) has been one of the most promising materials in bone tissue engineering in recent years, with characteristics such as biosafety, corrosion resistance, and wear resistance. However, the weak bioactivity of PEEK leads to its poor integration with bone tissues, restricting its application in biomedical fields. This research effectively fabricated composite porous scaffolds using a combination of PEEK, nano-hydroxyapatite (nHA), and carbon fiber (CF) by the process of fused deposition molding (FDM). The experimental study aimed to assess the impact of varying concentrations of nHA and CF on the biological performance of scaffolds. The incorporation of 10% CF has been shown to enhance the overall mechanical characteristics of composite PEEK scaffolds, including increased tensile strength and improved mechanical strength. Additionally, the addition of 20% nHA resulted in a significant increase in the surface roughness of the scaffolds. The high hydrophilicity of the PEEK composite scaffolds facilitated the in vitro inoculation of MC3T3-E1 cells. The findings of the study demonstrated that the inclusion of 20% nHA and 10% CF in the scaffolds resulted in improved cell attachment and proliferation compared to other scaffolds. This suggests that the incorporation of 20% nHA and 10% CF positively influenced the properties of the scaffolds, potentially facilitating bone regeneration. In vitro biocompatibility experiments showed that PEEK composite scaffolds have good biosafety. The investigation on osteoblast differentiation revealed that the intensity of calcium nodule staining intensified, along with an increase in the expression of osteoblast transcription factors and alkaline phosphatase activities. These findings suggest that scaffolds containing 20% nHA and 10% CF have favorable properties for bone induction. Hence, the integration of porous PEEK composite scaffolds with nHA and CF presents a promising avenue for the restoration of bone defects using materials in the field of bone tissue engineering.

5.
Int J Nanomedicine ; 17: 6561-6578, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36578441

RESUMEN

Background: Clinicians frequently face difficulties when trying to fix bone abnormalities. Gelatin-Alginate (GA) is frequently employed as a carrier because it is non-toxic, biodegradable, and has a three-dimensional network structure. Meanwhile, cerium oxide nanoparticles (nCeO2) demonstrated high antioxidant enzyme simulation activity. Therefore, in order to develop a porous hydrogel scaffold for the application of bone tissue engineering, an appropriate-type GA-nCeO2 hydrogel scaffold was developed and evaluated. Methods:  GA-nCeO2 hydrogel scaffold was prepared by the lyophilized method and characterized. The surface morphology and cell adhesion of the scaffold were observed by the scanning electron microscope. CCK8 and live-dead staining methods were used to evaluate its biological safety and cell proliferation. Then the osteogenic differentiation in early and late stages was discussed. The expression of osteogenic genes was also detected by RT-PCR. Finally, a bone defect model was made in SD rats, and bone formation in vivo was detected. Results:  The results showed that GA-nCeO2 hydrogel scaffold exhibited a typical three-dimensional porous structure with a mean pore ratio of 70.61 ± 1.94%. The GA-nCeO2 hydrogel was successfully endowed with simulated enzyme activity including superoxide dismutase (SOD) and catalase (CAT) after the addition of nCeO2. Osteoblasts demonstrated superior cell proliferation and adhesion on composite scaffolds, and both mineralization test and gene expression demonstrated the strong osteogenic potential of GA-nCeO2 hydrogel. The outcomes of hematoxylin and eosin (H&E) staining and Masson trichrome staining in the femoral defect model of SD rats further supported the scaffold's favorable biocompatibility and bone-promoting capacity. Conclusion: Due to its favorable safety, degradability, and bone formation property, GA-nCeO2 hydrogel was anticipated to be used as a potential bone defect healing material.


Asunto(s)
Nanoestructuras , Osteogénesis , Ratas , Animales , Osteogénesis/genética , Ingeniería de Tejidos/métodos , Hidrogeles/química , Gelatina/química , Andamios del Tejido/química , Alginatos/química , Ratas Sprague-Dawley , Diferenciación Celular , Regeneración Ósea
6.
Behav Brain Res ; 403: 113138, 2021 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-33493495

RESUMEN

Post-stroke depression(PSD) is a common complication and associates with poor physical recovery, low quality of life and high mortality after cerebral infarction. However, the pathogenesis of PSD have not been elucidated thoroughly now, and there is a lack of effective therapy in clinic. It reported that Saikosaponin A, one of the main constituents from Chinese herb Bupleurum chinense, has pharmacological activity in anti-depression. Thus, this study aimed to elucidate the potential effects and mechanisms of Saikosaponin A on the depression-like behavior after cerebral ischemic injury in rats. The rat model of PSD was induced by middle cerebral artery occlusion(MCAO) combined with chronic unpredictable mild stress(CUMS) and isolation. Behavior tests including open field test, beam-walking test, sucrose preference and forced swimming tests were performed. Western blot and immunohistochemistry were adopted to evaluate expression of phosphorylated cAMP response element binding protein(p-CREB), brain derived neurotrophic factor(BDNF) and apoptosis-related molecules in the dentate gyrus region of rat hippocampus. The TUNEL assay was used to determine neuronal apoptosis. We found that the rats subjected to MCAO combined with CUMS and isolation experienced significant depressive-like behavior. Administration of Saikosaponin A significantly ameliorated depressive-like behavior, and inhibited neuronal apoptosis, enhanced the level of p-CREB, BDNF and Bcl-2, reduced the level of Bax, Caspase-3 in the hippocampus of PSD rats. These results revealed that Saikosaponin A improved depression-like behavior and inhibited hippocampal neuronal apoptosis after cerebral ischemia, presumably through increasing the expression of BDNF, p-CREB and Bcl-2, as well as decreasing the level of Bax, Caspase-3.


Asunto(s)
Antidepresivos/farmacología , Apoptosis/efectos de los fármacos , Isquemia Encefálica/complicaciones , Factor Neurotrófico Derivado del Encéfalo/efectos de los fármacos , Depresión/tratamiento farmacológico , Depresión/etiología , Hipocampo/efectos de los fármacos , Accidente Cerebrovascular Isquémico/complicaciones , Ácido Oleanólico/análogos & derivados , Recuperación de la Función/efectos de los fármacos , Saponinas/farmacología , Animales , Antidepresivos/administración & dosificación , Conducta Animal/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Giro Dentado/efectos de los fármacos , Giro Dentado/metabolismo , Depresión/fisiopatología , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Masculino , Ácido Oleanólico/administración & dosificación , Ácido Oleanólico/farmacología , Ratas , Ratas Sprague-Dawley , Saponinas/administración & dosificación
7.
World J Gastroenterol ; 10(1): 105-11, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14695779

RESUMEN

AIM: To study the effect of red oil A5 on pancreatic cancer cells and its possible mechanisms. METHODS: Effect of different concentrations of red oil A5 on proliferation of three pancreatic cancer cell lines, AsPC-1, MiaPaCa-2 and S2013, was measured by (3)H-methyl thymidine incorporation. Time-dependent effects of 1:32 000 red oil A5 on proliferation of three pancreatic cancer cell lines, were also measured by (3)H-methyl thymidine incorporation, and Time-course effects of 1:32 000 red oil A5 on cell number. The cells were counted by Z1-Coulter Counter. Flow-cytometric analysis of cellular DNA content in the control and red oil A5 treated AsPC-1, MiaPaCa-2 and S2013 cells, were stained with propidium iodide. TUNEL assay of red oil A5-induced pancreatic cancer cell apoptosis was performed. Western blotting of the cytochrome c protein in AsPC-1, MiaPaCa-2 and S2013 cells treated 24 hours with 1:32 000 red oil A5 was performed. Proteins in cytosolic fraction and in mitochondria fraction were extracted. Proteins extracted from each sample were electrophoresed on SDS-PAGE gels and then were transferred to nitrocellulose membranes. Cytochrome c was identified using a monoclonal cytochrome c antibody. Western blotting of the caspase-3 protein in AsPC-1, MiaPaCa-2 and S2013 cells treated with 1:32 000 red oil A5 for 24 hours was carried out. Proteins in whole cellular lysates were electrophoresed on SDS-PAGE gels and then transferred to nitrocellulose membranes. Caspase-3 was identified using a specific antibody. Western blotting of poly-ADP ribose polymerase (PARP) protein in AsPC-1, MiaPaCa-2 and S2013 cells treated with 1:32 000 red oil A5 for 24 hours was performed. Proteins in whole cellular lysates were separated by electrophoresis on SDS-PAGE gels and then transferred to nitrocellulose membranes. PARP was identified by using a monoclonal antibody. RESULTS: Red oil A5 caused dose- and time-dependent inhibition of pancreatic cancer cell proliferation. Propidium iodide DNA staining showed an increase of the sub-G0/G1 cell population. The DNA fragmentation induced by red oil A5 in these three cell lines was confirmed by the TUNEL assay. Furthermore, Western blotting analysis indicated that cytochrome c was released from mitochondria to cytosol during apoptosis, and caspase-3 was activated following red oil A5 treatment which was measured by procaspase-3 cleavage and PARP cleavage. CONCLUSION: These findings show that red oil A5 has potent anti-proliferative effects on human pancreatic cancer cells with induction of apoptosis in vitro.


Asunto(s)
Apoptosis/efectos de los fármacos , Aceites de Pescado/farmacología , Neoplasias Pancreáticas , Caspasa 3 , Caspasas/metabolismo , Recuento de Células , División Celular/efectos de los fármacos , Línea Celular Tumoral/citología , Línea Celular Tumoral/efectos de los fármacos , Citocromos c/metabolismo , Humanos , Poli(ADP-Ribosa) Polimerasas/metabolismo , Timidina/farmacocinética
8.
World J Gastroenterol ; 9(12): 2745-50, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14669326

RESUMEN

AIM: To explore the mechanisms of effects of oil A on apoptosis of human pancreatic cancer cells. METHODS: Cellular DNA content was analyzed by flow cytometry. Western blotting was used for caspase-3 and PARP, caspase-7, caspase-9, cytochrome c, Bcl-2, Bax, Mcl-1, cyclinA, cyclin B1, cyclin D1, cyclin E, CDK2, CDK4, CDK6, P21, P27, GADD45, GADD153. RESULTS: The caspase-3, caspase-7, and caspase-9 activities were significantly increased as well as the cleavage of caspase-3, downstream substrate poly-ADP ribose polymerase (PARP) was induced. The amount of cytochrome c in the cytosolic fraction was increased, while the amount of cytochrome c in the mitochondrial fraction was decreased after oil A treatment. The anti-apoptosis proteins Bcl-2 and Mcl-1 were decreased in parallel and Bax increased, indicating that Bcl-2 family proteins-mitochondria-caspase cascade was responsible for oil-induced apoptosis. The proportion of cells in the G0/G1 decreased in MiaPaCa-2 and AsPC-1 cells after the treatment of oil A for 24 hours. The number of cells in S phase was increased in two cancer cell lines at 24 hours. Therefore, cells were significantly accumulated in G2/M phase. The cells with a sub-G0/G1 DNA content, a hallmark of apoptosis, were seen at 24 hours both in MiaPaCa-2 and AsPC-1 cells following exposure to oil A. The expression of cyclin A and cyclin B1 was slightly decreased and cyclin D1 levels were markedly lowered in MiaPaCa-2 cells. The expression of cyclin A and cyclin B1 was markedly decreased and cyclin D1 levels were slightly lowered in AsPC-1 cells, while cyclin E was not affected and the levels of CDK2, CDK4, and CDK6 were unchanged in MiaPaCa-2 and AsPC-1 cells. In response to oil A, P21 expression was increased, but P27 expression was not affected. The expression of both GADD45 and GADD153 was increased in two cell lines following oil A treatment. CONCLUSION: Oil A induces apoptosis of pancreatic cancer cells via activating caspase cascade, modifying cell cycle progress and changing cell cycle-regulating proteins and GADD expression.


Asunto(s)
Anticarcinógenos/farmacología , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Lípidos/farmacología , Neoplasias Pancreáticas/patología , Proteínas Potenciadoras de Unión a CCAAT/efectos de los fármacos , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Caspasas/efectos de los fármacos , Ciclinas/efectos de los fármacos , Daño del ADN/efectos de los fármacos , ADN de Neoplasias/efectos de los fármacos , Citometría de Flujo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Mitocondrias/fisiología , Neoplasias Pancreáticas/genética , Proteínas/efectos de los fármacos , Proteínas/metabolismo , Factor de Transcripción CHOP , Factores de Transcripción/efectos de los fármacos , Factores de Transcripción/metabolismo , Células Tumorales Cultivadas , Proteinas GADD45
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