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1.
World J Stem Cells ; 16(5): 486-498, 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38817333

RESUMEN

BACKGROUND: A decreased autophagic capacity of bone marrow mesenchymal stromal cells (BMSCs) has been suggested to be an important cause of decreased osteogenic differentiation. A pharmacological increase in autophagy of BMSCs is a potential therapeutic option to increase osteoblast viability and ameliorate osteoporosis. AIM: To explore the effects of sinomenine (SIN) on the osteogenic differentiation of BMSCs and the underlying mechanisms. METHODS: For in vitro experiments, BMSCs were extracted from sham-treated mice and ovariectomized mice, and the levels of autophagy markers and osteogenic differentiation were examined after treatment with the appropriate concentrations of SIN and the autophagy inhibitor 3-methyladenine. In vivo, the therapeutic effect of SIN was verified by establishing an ovariectomy-induced mouse model and by morphological and histological assays of the mouse femur. RESULTS: SIN reduced the levels of AKT and mammalian target of the rapamycin (mTOR) phosphorylation in the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR signaling pathway, inhibited mTOR activity, and increased autophagy ability of BMSCs, thereby promoting the osteogenic differentiation of BMSCs and effectively alleviating bone loss in ovariectomized mice in vivo. CONCLUSION: The Chinese medicine SIN has potential for the treatment of various types of osteoporosis, bone homeostasis disorders, and autophagy-related diseases.

2.
ACS Nano ; 17(16): 15449-15465, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37530575

RESUMEN

Ions play a vital role in regulating various biological processes, including metabolic and immune homeostasis, which involves tumorigenesis and therapy. Thus, the perturbation of ion homeostasis can induce tumor cell death and evoke immune responses, providing specific antitumor effects. However, antitumor strategies that exploit the effects of multiion perturbation are rare. We herein prepared a pH-responsive nanomodulator by coloading curcumin (CU, a Ca2+ enhancer) with CaCO3 and MnO2 into nanoparticles coated with a cancer cell membrane. This nanoplatform was aimed at reprogramming the tumor microenvironment (TME) and providing an antitumor treatment through ion fluctuation. The obtained nanoplatform, called CM NPs, could neutralize protons by decomposing CaCO3 and attenuating cellular acidity, they could generate Ca2+ and release CU, elevating Ca2+ levels and promoting ROS generation in the mitochondria and endoplasmic reticulum, thus, inducing immunogenic cell death. Mn2+ could decompose the endogenous H2O2 into O2 to relieve hypoxia and enhance the sensitivity of cGAS, activating the cGAS-STING signaling pathway. In addition, this strategy allowed the reprogramming of the immune TME, inducing macrophage polarization and dendritic cell maturation via antigen cross-presentation, thereby increasing the immune system's ability to combat the tumor effectively. Moreover, the as-prepared nanoparticles enhanced the antitumor responses of the αPD1 treatment. This study proposes an effective strategy to combat tumors via the reprogramming of the tumor TME and the alteration of essential ions concentrations. Thus, it shows great potential for future clinical applications as a complementary approach along with other multimodal treatment strategies.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Calcio , Manganeso , Peróxido de Hidrógeno , Compuestos de Manganeso/farmacología , Microambiente Tumoral , Óxidos/farmacología , Inmunoterapia , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral
3.
3 Biotech ; 10(4): 156, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32181118

RESUMEN

To investigate the application of short elastin-like polypeptides (ELPs) in the purification of bioactive proteins, short hydrophobic ELP[I] n (n = 30, 40, 50) tags were constructed. Both the ELP[I] n tags and the ELP[I] n -Trx fusion proteins could be stably expressed in Escherichia coli and purified by inverse transition cycling, respectively. Total protein concentrations determined by BCA protein assay showed that the yield of the fusion proteins decreased with increasing ELP length. Measurements of the inverse transition temperature (T t) of the ELP[I] n -Trx under different salts or PEG8000 concentrations showed decreased T t upon elevated concentrations; while, all the T ts were suitable for generating proteins from 4 to 37.5 ºC. Furthermore, to identify a linker peptide for bioactive protein production without the need to remove the ELP[I] n tag, the activity of eGFP protein fused with ELP[I]30 tag by either a poly-N or a G4S linker was quantified using a fluorescence spectrophotometer. The results indicated that the ELP[I]30-eGFP fusion proteins with the poly-N linker showed higher fluorescence levels than those with the G4S linker. Our results demonstrated that short ELP[I] n tags with low T t were useful in protein expression and purification, and poly-N linker played the key role in producing bioactive proteins without the need to remove the ELPs.

4.
J Food Sci ; 83(4): 1165-1172, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29577290

RESUMEN

Environmental and plant factors (soil condition, variety, season, and maturity) and exposure risks of aluminum (Al), manganese (Mn), lead (Pb), cadmium (Cd), and copper (Cu) in tea leaves were investigated. The concentrations of these metals in tea leaves could not be predicted by their total concentrations in the soil. During any one season, there were differences in Al, Mn, and Cd levels between tea varieties. Seasonally, autumn tea and/or summer tea had far higher levels of Al, Mn, Pb, and Cd than did spring tea. Tea leaf maturity positively correlated with the concentrations of Al, Mn, Pb, and Cd, but negatively with Cu. The calculated average daily intake doses (mg/ [kg•d]) for these metal elements were 0.14 (Al), 0.11 (Mn), 2.70 × 10-3 (Cu), 2.80 × 10-4 (Pb), and 2.88 × 10-6 (Cd). The hazard quotient values of each metal were all significantly lower than risk level (=1), suggesting that, for the general population, consumption of tea does not result in the intake of excessive amounts of Al, Mn, Pb, Cd, or Cu. This study identified the factors that can be monitored in the field to decrease consumer exposure to Al and Mn through tea consumption. PRACTICAL APPLICATION: Environmental and plant factors influence aluminum and heavy metal accumulation in tea leaves. Consumers of tea are not ingesting excessive Al, Mn, Pb, Cd, or Cu. Trackable factors were identified to manage exposure levels.


Asunto(s)
Aluminio/análisis , Seguridad de Productos para el Consumidor , Exposición a Riesgos Ambientales/análisis , Metales Pesados/análisis , Hojas de la Planta/química , Té/química , China , Contaminación de Alimentos/análisis , Política Nutricional , Medición de Riesgo , Factores de Riesgo , Estaciones del Año , Contaminantes del Suelo/análisis
5.
Zhongguo Gu Shang ; 28(12): 1117-20, 2015 Dec.
Artículo en Chino | MEDLINE | ID: mdl-26911120

RESUMEN

OBJECTIVE: To explore the imaging characteristics and operation outcomes of intramedullary schwannoma in thoracolumbar spine. METHODS: From June 2005 to December 2012,17 patients with intramedullary schwannoma in thoracolumbar spine were operated through posterior approach, including 11 males and 6 females with an average age of 53 years old ranging from 46 to 67 years old. The courses of disease ranged from 3 to 5 years (averaged 3.3 years). Thoracic patients manifested chest and back pain,numbness and inability on lower limb gradually, unsteady gait. Lumbar patients manifested low back pain,radiating pain and numbness on lower limb, intermittent claudication. Preoperative VAS score was 5 to 8 with an average of 6.12. Eleven patients suffered from never injury, 4 cases were grade C, 5 cases were grade D and 2 cases were grade E according to Frankel classification. Three patients were injured on thoracic segments, 5 patients were on thoracolumbar segments, 3 patients on lumbar segments and 6 patients on lumbosacral segment confirmed by CT and MRI. Five patients were epidural, 12 were intradural extramedullary. Six patients underwent spinal decompression and tumor resection simply, eleven patients underwent spinal decompression, tumor resection, internal fixation and bone graft fusion. RESULTS: No injury of blood vessel or spinal cord occurred during operation, cutting healed well. All patients were followed up from 12 to 60 months with an average of 32 months. Chest and back pain, low back pain, radiating pain and numbness on lower limb were improved significantly. VAS score at final follow-up was 0 to 3 (averaged 1.5). According to Frankel classification, 5 cases were grade D, and 6 cases were grade E at final follow-up. CONCLUSION: MRI is an effective method in diagnosis of intramedullary schwannoma in thoracolumbar spine. Operative method is choosed by imaging expression, and the aim is effectively decompression of spine, reconstruction of stability of spine.


Asunto(s)
Vértebras Lumbares/cirugía , Neurilemoma/cirugía , Neoplasias de la Columna Vertebral/cirugía , Vértebras Torácicas/cirugía , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neurilemoma/patología , Neoplasias de la Columna Vertebral/patología
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