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1.
Biofouling ; 37(3): 257-266, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33870823

RESUMEN

Biofouling is a widespread phenomenon in oceans worldwide. With increasing human development and activities in open and coastal waters, and due to the environmental impact of AF organotins and copper-based paint, the demand for nontoxic antifouling (AF) paints is increasing. Various bioassays for antimicrobial activity, anti-biofilm formation and anti-barnacle settlement were established to evaluate the possibility of using marine natural products as AF agents. A series of natural products, isolated from the marine-derived fungi Trichoderma atroviride and T. reesei, were evaluated for their AF activity. One pyrone-type compound (1) demonstrated significant inhibitory activities toward barnacle cyprid settlement. Furthermore, a series of pyrone analogues (S1-S6) were synthesized, and their bioactivities were evaluated in the established systems. The results showed that compounds S5 and S6 exhibited a broad spectrum of bioactivities, such as anti-barnacle settlement, anti-biofilm formation and antimicrobial activities.


Asunto(s)
Incrustaciones Biológicas , Policétidos , Incrustaciones Biológicas/prevención & control , Humanos , Hypocreales , Océanos y Mares , Pironas/farmacología
2.
Biochem Biophys Res Commun ; 503(2): 536-543, 2018 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-29787753

RESUMEN

BACKGROUND: miR-193a has been shown to be involved in a variety of biological processes, including cell proliferation, differentiation, and apoptosis. However, little is known about how miR-193a regulates osteogenic differentiation. METHODS: We employed RT-qPCR to determine the level of miR-193a and mRNA level of HMGB1 and osteoblast-specific markers (Runx2, ALP, OSX, OCN). Besides, westernblot was used to probe protein level of phosphorylated MAPK family members and ß-catenin. Bioinformatic analysis was used to predict the putative binding sequence of miR-193a to the 3'-UTR of HMGB1 and we confirmed this result by dual luciferase reporter assay. Alizarin red staining assay (ARS) and alkaline phosphatase activity (ALP) were performed to detect osteogenic differentiation. RESULTS: miR-193a was downregulated in OM (osteogenic medium)induced hBMSC. More interestingly, we found that miR-193a mimic attenuated matrix mineralization and alkaline phosphatase activity, whereas miR-193a inhibitor exerted the opposite phenotypes. Mechanistically, we observed that miR-193a played an inhibitory role in expression of osteoblast-specific markers and activation of MAPK and Wnt signaling pathways. Bioinformatic analysis and dual luciferase assay demonstrated that miR-193a directly targeted 3'-UTR of HMGB1. Furthermore, we overexpressed HMGB1 in miR-193a overexpressed hBMSC to establish that HMGB1 acted as downstream target of miR-193a-inhibited osteogenic differentiation. CONCLUSIONS: Here, we reveal miR-193a plays a suppressive role in osteogenic differentiation of hBMSC via targeting HMGB1. These findings provide a novel mechanism underlying osteogenic differentiation and offer therapeutical strategy for bone formation.


Asunto(s)
Proteína HMGB1/genética , Células Madre Mesenquimatosas/citología , MicroARNs/genética , Osteoblastos/citología , Osteogénesis , Diferenciación Celular , Células Cultivadas , Regulación hacia Abajo , Humanos , Sistema de Señalización de MAP Quinasas , Masculino , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/metabolismo , Regulación hacia Arriba , Vía de Señalización Wnt
3.
Arch Orthop Trauma Surg ; 136(3): 371-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26718351

RESUMEN

BACKGROUND: Despite several randomized controlled trials comparing operative to nonoperative management of primary patellar dislocation, the optimal management of this condition remains a subject of controversy. The aim of this study was to compare surgical to conservative treatment of outcomes for primary patellar dislocation by meta-analysis all the relative randomized controlled trials. STUDY DESIGN: Meta-analysis. METHODS: After searching multiple online databases (MEDILINE, EMBASE, CLINICAL, OVID, BISOS and Cochrane registry of controlled clinical trials), eight randomized controlled trials including 430 patients were meta-analyzed in which operative treatment was compared with non-operative treatment for primary patellar dislocation. Outcomes evaluated were redislocation rate, Kujala score, episode of instability, Tegner activity score, Hughston visual analog score (VAS) and patient satisfaction. RESULTS: Outcomes on recurrent patellar dislocation (P = 0.004) and Hughston VAS (P = 0.03) were statistically significant in favor of operative management. Tegner activity score (P < 0.00001) was significantly higher in favor of conservative treatment, though only a few studies were identified. There was no significant difference between the two treatments regarding episode of instability (P = 0.41), Kujala score (P = 0.32) or patient satisfaction (P = 0.49). CONCLUSION: Surgical treatment may be better than conservative treatment for patients with primary patellar dislocation on incidence of redislocation. However, since these findings are built on a limited number of studies available, well-designed, multicenter clinical trials with long-term follow-up are required to provide more solid evidence concerning optimal strategies.


Asunto(s)
Procedimientos Ortopédicos/métodos , Dolor , Luxación de la Rótula/terapia , Satisfacción del Paciente , Bases de Datos Factuales , Humanos , Inestabilidad de la Articulación/epidemiología , Complicaciones Posoperatorias/epidemiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Proyectos de Investigación
4.
J Hazard Mater ; 477: 135105, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39047551

RESUMEN

Incense-burning smoke is a deleterious air pollutant that initiates cytotoxic effects by inducing apoptosis in lung epithelial cells and also acts as a risk factor for lung cancers. Auramine, an ingredient of incense smoke, has been implicated in tumor progression and cellular sensitivity in non-small cell lung cancer (NSCLC) towards anti-cancer agents through unclear mechanisms. Tumor protein p53 (TP53)-activated long intergenic non-coding RNA-p21 (lincRNA-p21) undertakes a pivotal role in regulating cell apoptosis and chemosensitivity. TP53 mutations prevalent in 50% of NSCLC, contribute to diminished therapeutic efficacy. However, the influence of auramine on chemotherapy-induced lincRNA-p21 expression and apoptosis in NSCLC with different TP53 genetic statuses remains unexplored. This study disclosed that both wild-type p53 (wtp53) and mutant p53 (mutp53) mediate lincRNA-p21 expression, albeit through distinct promoter enhancers, p53-response element (p53RE) and non-B DNA structure G-quadruplex (GQ), respectively. Intriguingly, auramine functions as an effective stabilizer of the GQ structure, augmenting mutp53-mediated lincRNA-p21 expression and enhancing apoptosis and cellular sensitivity to chemotherapy in mutp53-expressing NSCLC cells. These findings suggest a mechanism by which mutp53, in the presence of auramine, is endowed with tumor-suppressing function akin to wtp53, thereby aiding in combating chemoresistance in NSCLC cells harboring TP53 mutations.

5.
ACS Nano ; 17(14): 13158-13175, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37436002

RESUMEN

Tumour hypoxia plays an important role in modulating tumorigenesis, angiogenesis, invasion, immunosuppression, resistance to treatment, and even maintenance of the stemness of cancer stem cells (CSCs). Moreover, the targeting and treatment of hypoxic cancer cells and CSCs to reduce the influence of tumor hypoxia on cancer therapy remains an imperative clinical problem that needs to be addressed. Since cancer cells upregulate the expression of glucose transporter 1 (GLUT1) through the Warburg effect, we considered the possibility of GLUT1-mediated transcytosis in cancer cells and developed a tumor hypoxia-targeting nanomedicine. Our experimental results indicate that glucosamine-labeled liposomal ceramide can be efficiently transported between cancer cells by GLUT1 transporters and substantially accumulated in the hypoxic area in in vitro CSC spheroids and in vivo tumor xenografts. We also verified the effects of exogenous ceramide on tumor hypoxia, including important bioactivities such as upregulation of p53 and retinoblastoma protein (RB), downregulation of hypoxia-inducible factor-1 alpha (HIF-1α) expression, disruption of the OCT4-SOX2 network of stemness, and inhibition of CD47 and PD-L1 expression. To achieve an ideal therapeutic outcome, we combined treatment of glucosamine-labeled liposomal ceramide with paclitaxel and carboplatin, and we found an excellent synergistic effect, with tumor clearance being noted in three-fourths of the mice. Overall, our findings provide a potential therapeutic strategy for the treatment of cancer.


Asunto(s)
Hipoxia , Neoplasias , Humanos , Ratones , Animales , Transportador de Glucosa de Tipo 1/metabolismo , Hipoxia/metabolismo , Hipoxia de la Célula , Liposomas/farmacología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Transcitosis , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Línea Celular Tumoral , Neoplasias/patología
6.
Zhonghua Yi Xue Za Zhi ; 92(41): 2930-3, 2012 Nov 06.
Artículo en Zh | MEDLINE | ID: mdl-23328244

RESUMEN

OBJECTIVE: To explore the feasibility and safety of mdr1 gene transferred into placenta derived mesenchymal stem cells (P-MSCs) by reconstructed retroviral vector. METHODS: Human P-MSCs were isolated and expanded by Percoll density gradient and then transduced repeatedly by reconstructed retroviral vector containing mdr1 gene. The transfection and expression of mdr1 gene was detected by reverse transcription-polymerase chain reaction (RT-PCR) and fluorescence-activated cell sorting (FACS). Meanwhile, the biological features of mdr1-MSCs were identified and analyzed. RESULTS: The expression of mdr1mRNA was found in transfected cells. The expression of P-glycoprotein (P-gp) encoded by mdr1 gene was (27.6 ± 5.1)% in the transfected P-MSCs cells versus (0.4 ± 0.1)% in the non-transfected P-MSCs cells (t = 14.291, P < 0.01). The percent of P-MSCs at quiescent phase (G0/G1 phase) was around 95.40% and it was in accord with the characterization of stem cells. The mdr1-MSCs exhibited typical ultrastructures of low-differentiated stem cells. Moreover, they still retained the potency of adipogenic and osteogenic differentiation in the presence of appropriate conditioned media. CONCLUSION: A stable expression of P-gp may be obtained by reconstructed retroviral-mediated transfection in vitro. And transfected MSCs retain the characteristics of stem cells.


Asunto(s)
Resistencia a Múltiples Medicamentos/genética , Genes MDR , Células Madre Mesenquimatosas/citología , Placenta/citología , Transfección , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Células Cultivadas , Femenino , Vectores Genéticos , Humanos , Embarazo
7.
Methods Mol Biol ; 2505: 45-58, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35732935

RESUMEN

The surface-assisted laser desorption/ionization (SALDI) technique uses inorganic materials to aid desorption and ionization of molecules. SALDI is suitable for analyzing small molecules due to the absence of interfering signals in the low m/z range originating from the organic matrix. Imaging mass spectrometry (IMS) is a versatile imaging approach with high spatial resolution for analyzing various molecular species, but its application depends heavily on the ionization method. We have developed a functionalized titanium dioxide (TiO2) nanowire as a solid substrate for SALDI-MS detection of low-molecular-weight molecules. We apply this novel substrate for imprinting fragile specimens such as petals and further SALDI-IMS analysis. The TiO2 nanowire substrate is prepared from a commercial Ti plate by a hydrothermal process and subsequently chemically modified to improve the quality and selectivity of imprinting as well as the sensitivity of SALDI-IMS analysis. Here, the functionalized TiO2 nanowire substrate is applied to visualize the distribution of vinca alkaloids in the petal of Madagascar periwinkle (Catharanthus roseus).


Asunto(s)
Catharanthus , Alcaloides de la Vinca , Diagnóstico por Imagen/métodos , Rayos Láser , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
8.
Commun Biol ; 5(1): 454, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35551233

RESUMEN

Bacterial polyynes are highly active natural products with a broad spectrum of antimicrobial activities. However, their detailed mechanism of action remains unclear. By integrating comparative genomics, transcriptomics, functional genetics, and metabolomics analysis, we identified a unique polyyne resistance gene, masL (encoding acetyl-CoA acetyltransferase), in the biosynthesis gene cluster of antifungal polyynes (massilin A 1, massilin B 2, collimonin C 3, and collimonin D 4) of Massilia sp. YMA4. Crystallographic analysis indicated that bacterial polyynes serve as covalent inhibitors of acetyl-CoA acetyltransferase. Moreover, we confirmed that the bacterial polyynes disrupted cell membrane integrity and inhibited the cell viability of Candida albicans by targeting ERG10, the homolog of MasL. Thus, this study demonstrated that acetyl-CoA acetyltransferase is a potential target for developing antifungal agents.


Asunto(s)
Acetil-CoA C-Acetiltransferasa , Antifúngicos , Acetil-CoA C-Acetiltransferasa/genética , Acetil-CoA C-Acetiltransferasa/metabolismo , Antifúngicos/farmacología , Bacterias/metabolismo , Candida albicans/genética , Candida albicans/metabolismo , Poliinos/metabolismo , Poliinos/farmacología
9.
Int J Mol Sci ; 12(8): 5319-29, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21954361

RESUMEN

Oleanolic acid and ursolic acid are the main active components in fruit of Ligustrum lucidum Ait, and possess anticancer, antimutagenic, anti-inflammatory, antioxidative and antiprotozoal activities. In this study, microwave-assisted extraction of oleanolic acid and ursolic acid from Ligustrum lucidum was investigated with HPLC-photodiode array detection. Effects of several experimental parameters, such as type and concentration of extraction solvent, ratio of liquid to material, microwave power, extraction temperature and microwave time, on the extraction efficiencies of oleanolic acid and ursolic acid from Ligustrum lucidum were evaluated. The influence of experimental parameters on the extraction efficiency of ursolic acid was more significant than that of oleanolic acid (p < 0.05). The optimal extraction conditions were 80% ethanol aqueous solution, the ratio of material to liquid was 1:15, and extraction for 30 min at 70 °C under microwave irradiation of 500 W. Under optimal conditions, the yields of oleanolic acid and ursolic acid were 4.4 ± 0.20 mg/g and 5.8 ± 0.15 mg/g, respectively. The results obtained are helpful for the full utilization of Ligustrum lucidum, which also indicated that microwave-assisted extraction is a very useful method for extraction of oleanolic acid and ursolic acid from plant materials.


Asunto(s)
Fraccionamiento Químico/métodos , Ligustrum/química , Microondas , Ácido Oleanólico/química , Extractos Vegetales/química , Triterpenos/química , Estructura Molecular , Solventes/química , Temperatura , Ácido Ursólico
10.
Fa Yi Xue Za Zhi ; 27(4): 286-9, 294, 2011 Aug.
Artículo en Zh | MEDLINE | ID: mdl-21913561

RESUMEN

Traumatic brain injury (TBI) is a highly complex multi-factorial disorder. Animal models of TBI are used to elucidate primary and secondary injury mechanisms and pathophysiological changes and to provide the diagnostic and therapeutical basis for TBI. The choices of animal models depend upon the research objectives. However, various animal models have limitations. The models only can duplicate the pivotal injury mechanisms or a certain important pathophysiological course. The characteristics of human TBI can not fully be reflected by using these models. In the review, animal models of traumatic brain injury are classified as dynamic direct brain injury, indirect dynamic brain injury and combined neuro-traumatic models. Several common models are described for consideration.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Encéfalo/fisiopatología , Modelos Animales de Enfermedad , Traumatismos Cerrados de la Cabeza/fisiopatología , Traumatismos Penetrantes de la Cabeza/fisiopatología , Animales , Fenómenos Biomecánicos , Encéfalo/patología , Lesiones Encefálicas/patología , Lesión Axonal Difusa/patología , Lesión Axonal Difusa/fisiopatología , Medicina Legal , Traumatismos Cerrados de la Cabeza/patología , Traumatismos Penetrantes de la Cabeza/patología , Humanos , Ratones , Ratas , Reproducibilidad de los Resultados
11.
Front Pharmacol ; 12: 614673, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34267653

RESUMEN

The proviral integration site for moloney murine leukemia virus 1 (Pim1) is a serine/threonine kinase and able to promote cell proliferation, survival and drug resistance. Overexpression of Pim1 has been observed in many cancer types and is associated with the poor prognosis of breast cancer. However, it remains unclear whether Pim1 kinase is a potential therapeutic target for breast cancer patients. In this study, we found that Pim1 expression was strongly associated with HER2 expression and that HER2-overexpressing breast cancer cells were more sensitive to Pim1 inhibitor-induced inhibitions of cell viability and metastatic ability. Mechanistically, Pim1 inhibitor suppressed the expression of HER2 at least in part through transcriptional level. More importantly, Pim1 inhibitor overcame the resistance of breast cancer cells to HER2 tyrosine kinase inhibitor lapatinib. In summary, downregulation of HER2 by targeting Pim1 may be a promising and effective therapeutic approach not only for anti-cancer growth but also for circumventing lapatinib resistance in HER2-positive breast cancer patients.

12.
ISME J ; 15(6): 1858-1861, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33619352

RESUMEN

Bacteria and fungi secrete many natural products that inhibit each other's growth and development. The dynamic changes in secreted metabolites that occur during interactions between bacteria and fungi are complicated. Pyochelin is a siderophore produced by many Pseudomonas and Burkholderia species that induces systemic resistance in plants and has been identified as an antifungal agent. Through imaging mass spectrometry and metabolomics analysis, we found that Phellinus noxius, a plant pathogen, can modify pyochelin and ent-pyochelin to an esterification product, resulting in reduced iron-chelation and loss of antifungal activity. We also observed that dehydroergosterol peroxide, the fungal metabolite, is only accumulated in the presence of pyochelin produced through bacteria-fungi interactions. For the first time, we show the fungal transformation of pyochelin in the microbial interaction. Our findings highlight the importance of understanding the dynamic changes of metabolites in microbial interactions and their influences on microbial communities.


Asunto(s)
Antifúngicos , Sideróforos , Antifúngicos/farmacología , Hongos , Hierro , Pseudomonas , Pseudomonas aeruginosa
13.
Oncogene ; 40(29): 4796-4808, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34155348

RESUMEN

The tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) have been widely used for non-small cell lung cancer (NSCLC) patients, but the development of acquired resistance remains a therapeutic hurdle. The reduction of glucose uptake has been implicated in the anti-tumor activity of EGFR TKIs. In this study, the upregulation of the active sodium/glucose co-transporter 1 (SGLT1) was found to confer the development of acquired EGFR TKI resistance and was correlated with the poorer clinical outcome of the NSCLC patients who received EGFR TKI treatment. Blockade of SGLT1 overcame this resistance in vitro and in vivo by reducing glucose uptake in NSCLC cells. Mechanistically, SGLT1 protein was stabilized through the interaction with PKCδ-phosphorylated (Thr678) EGFR in the TKI-resistant cells. Our findings revealed that PKCδ/EGFR axis-dependent SGLT1 upregulation was a critical mechanism underlying the acquired resistance to EGFR TKIs. We suggest co-targeting PKCδ/SGLT1 as a potential strategy to improve the therapeutic efficacy of EGFR TKIs in NSCLC patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Transportador 1 de Sodio-Glucosa , Regulación hacia Arriba
14.
Oncogene ; 40(6): 1162-1175, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33335306

RESUMEN

Smoker patients with non-small cell lung cancer (NSCLC) have poorer prognosis and survival than those without smoking history. However, the mechanisms underlying the low response rate of those patients to EGFR tyrosine kinase inhibitors (TKIs) are not well understood. Here we report that exposure to cigarette smoke extract enhances glycolysis and attenuates AMP-activated protein kinase (AMPK)-dependent inhibition of mTOR; this in turn reduces the sensitivity of NSCLC cells with wild-type EGFR (EGFRWT) to EGFR TKI by repressing expression of liver kinase B1 (LKB1), a master kinase of the AMPK subfamily, via CpG island methylation. In addition, LKB1 expression is correlated positively with sensitivity to TKI in patients with NSCLC. Moreover, combined treatment of EGFR TKI with AMPK activators synergistically increases EGFR TKI sensitivity. Collectively, the current study suggests that LKB1 may serve as a marker to predict EGFR TKI sensitivity in smokers with NSCLC carrying EGFRWT and that the combination of EGFR TKI and AMPK activator may be a potentially effective therapeutic strategy against NSCLC with EGFRWT.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Proteínas Serina-Treonina Quinasas/genética , Serina-Treonina Quinasas TOR/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Carcinoma de Pulmón de Células no Pequeñas/inducido químicamente , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Fumar Cigarrillos/efectos adversos , Islas de CpG/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Receptores ErbB/genética , Xenoinjertos , Humanos , Ratones , Mutación/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/genética , Transducción de Señal/efectos de los fármacos , Fumar/efectos adversos
15.
Eur Biophys J ; 39(8): 1229-42, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20140669

RESUMEN

At least 25 human proteins can fold abnormally to form pathological deposits that are associated with several degenerative diseases. Despite extensive investigation on amyloid fibrillation, the detailed molecular mechanisms remain rather elusive and there are currently no effective cures for treating these amyloid diseases. The present study examined the effects of dithiothreitol on the fibrillation of hen egg-white lysozyme (HEWL). Our results revealed that the fibrillation of hen lysozyme was significantly inhibited by reduced dithiothreitol (DTT(red)) while oxidized dithiothreitol (DTT(ox)) had no anti-aggregating activity. Effective inhibitory activity against hen lysozyme fibrillation was observed only when DTT(red) was added within 8 days of incubation. Our results showed that the initial addition of DTT(red) interacted with HEWL, leading to a loss in conformational stability. It was concluded from our findings that DTT(red)-induced attenuation of HEWL fibrillation may be associated with disulfide disruption and extensive structural unfolding of HEWL. Our data may contribute to rational design of effective therapeutic strategies for amyloid diseases.


Asunto(s)
Amiloide/metabolismo , Proteínas Aviares/metabolismo , Fármacos del Sistema Nervioso Central/farmacología , Ditiotreitol/farmacología , Proteínas del Huevo/metabolismo , Muramidasa/metabolismo , Multimerización de Proteína/efectos de los fármacos , Animales , Fármacos del Sistema Nervioso Central/química , Pollos , Ditiotreitol/química , Clara de Huevo , Femenino , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Oxidación-Reducción , Conformación Proteica/efectos de los fármacos , Pliegue de Proteína/efectos de los fármacos , Estabilidad Proteica/efectos de los fármacos , Termodinámica , Urea/metabolismo
16.
Materials (Basel) ; 13(14)2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708207

RESUMEN

To improve simulation accuracy and efficiency of probabilistic fatigue life evaluation for turbine rotor, a decomposed collaborative modeling approach is presented. In this approach, the intelligent Kriging modeling (IKM) is firstly proposed by combining the Kriging model (KM) and an intelligent algorithm (named as dynamic multi-island genetic algorithm), to tackle the multi-modality issues for obtaining optimal Kriging parameters. Then, the decomposed collaborative IKM (DCIKM) comes up by fusing the IKM into decomposed collaborative (DC) strategy, to address the high-nonlinearity problems for accelerating simulation efficiency. Moreover, the DCIKM-based probabilistic fatigue life evaluation theory is introduced. The probabilistic fatigue life evaluation of turbine rotor is regarded as case study to verify the presented approach; the evaluation results reveal that the probabilistic fatigue life of turbine rotor is 3296 cycles. The plastic strain range ∆εp and fatigue strength coefficient σf' are the main affecting factors to fatigue life, whose effect probability are 28% and 22%, respectively. By comparing with direct Monte Carlo method, KM method, IKM method and DC response surface method, the presented DCIKM is validated to hold high efficiency and accuracy in probabilistic fatigue life evaluation.

17.
Bone ; 131: 115059, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31521826

RESUMEN

BACKGROUND: The osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs) is critical for bone homeostasis. Here, we investigated the regulation of Galectin-3 and tripartite motif protein 16 (TRIM16) on osteogenic differentiation of hBMSCs through autophagy. METHODS: Quantitative PCR (qPCR) and western blot were performed to determine the expression of osteogenic markers, autophagic markers, Galectin-3 and TRIM16. Short-hairpin RNAs (shRNAs) and overexpression plasmids were used to manipulate the expression of Galectin-3, TRIM16 and Unc-51 like autophagy activating kinase 1 (ULK1). Alkaline phosphatase (ALP) activity was measured by ALP staining assay. Calcium deposition in differentiated hBMSCs was assessed by Alizarin Red S staining. LC3 puncta formation was monitored by immunofluorescence staining. The interaction between indicated proteins was confirmed by co-immunoprecipitation (Co-IP) assay. RESULTS: Either Galectin-3 or TRIM16 knockdown led to impaired ALP activity, reduced calcium deposition, down-regulation of pro-osteogenic markers as well as restrained autophagy in osteogenic-induced hBMSCs. However, overexpression of Galectin-3 or TRIM16 promoted osteogenic differentiation of hBMSCs, which was then compromised by autophagy inhibition. Co-IP experiment demonstrated that TRIM16 associated with Galectin-3 through ULK1. Meanwhile, osteogenic induction enhanced the association between TRIM16 and ULK1 or coiled-coil myosin-like BCL2-interacting protein (Beclin1), and TRIM16 increased the stability of ULK1 and Beclin1. Moreover, either TRIM16 or ULK1 knockdown dampened the pro-osteogenic effect of Galectin-3, which elucidated that Galectin-3 mediated osteogenic differentiation was at least partly dependent on TRIM16 and ULK1. CONCLUSION: In summary, the present study revealed Galectin-3 and TRIM16 co-regulated osteogenic differentiation of hBMSCs at least partly via enhancing autophagy, which might provide a promising approach for osteoporosis treatment in future.


Asunto(s)
Galectina 3 , Células Madre Mesenquimatosas , Osteogénesis , Proteínas de Motivos Tripartitos , Ubiquitina-Proteína Ligasas , Autofagia , Médula Ósea , Diferenciación Celular , Células Cultivadas , Galectina 3/genética , Humanos , Células Madre Mesenquimatosas/citología
18.
Zhonghua Yi Xue Za Zhi ; 89(39): 2793-6, 2009 Oct 27.
Artículo en Zh | MEDLINE | ID: mdl-20137607

RESUMEN

OBJECTIVE: To transfer multidrug resistance gene (mdr1) into human placental mesenchymal stem cells (P-MSCs) by retroviral vector and assess the effects of mdr1 gene transduction upon biological features of P-MSCs. METHODS: Human P-MSCs were isolated from trypsin-digested term placentas and then transduced by reconstructed retroviral vector containing mdr1 gene and green fluorescent protein (GFP) reporter gene. Flow cytometric analysis was employed to determine the immunophenotypes of transfected P-MSCs. And the proliferation and cell cycle were detected by methyl thiazolyl tetrazolium and propidium iodide staining. Ultrastructures of transfected P-MSCs were observed and different induction conditions used to direct the cells to differentiate into adipocytes and osteoblasts. RESULTS: The transfected P-MSCs still expressed stem cell markers such as CD29, CD44 and CD73. The mean cumulative time of population doubling was 23.9 hours. The cellular cycle retained the proliferative characterization of stem cells. Ultrastructural features of transfected P-MSCs included increased surface microvilli, abundant mitochondria and slightly swollen rough endoplasmic reticulum. Furthermore these transfected cells demonstrated osteogenic and adipogenic differentiation potentials under appropriate conditions. CONCLUSION: The mdr1 gene transduction by retroviral vector in vitro has no significant effect upon biological characteristics of P-MSCs. It might provide experimental references for the application of P-MSCs in high-dose tumor chemotherapy.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Resistencia a Múltiples Medicamentos/genética , Células Madre Mesenquimatosas/citología , Placenta/citología , Transfección , Diferenciación Celular , Resistencia a Antineoplásicos/genética , Femenino , Técnicas de Transferencia de Gen , Vectores Genéticos , Humanos , Embarazo
19.
Injury ; 50(11): 1952-1958, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31445830

RESUMEN

Currently, accurate diagnosis and successful treatment of infection after fracture fixation (IAFF) still impose great challenges. According to the onset of infection symptoms after implantation, IAFF is classified as early infection (<2 weeks), delayed infection (2∼10 weeks) and late infection (>10 weeks). Confirmation of IAFF should be supported by histopathological tests of intraoperative specimens which confirm infection, cultures from at least two suspected infection sites which reveal the same pathogen, a definite sinus or fistula which connects directly the bone or the implant, and purulent drainage from the wound or presence of pus during surgery. Diagnosis of IAFF is built on comprehensive assessment of medical history, clinical signs and symptoms of the patient, and imaging and laboratory tests. The gold standard of diagnosis is histopathological tests. Treatment of IAFF consists of radical debridement, adequate irrigation, implant handling, systematic and local antibiotics, reconstruction of osseous and/or soft tissue defects, and functional rehabilitation of an affected limb. Early accurate diagnosis and appropriate treatment of IAFF play a key role in increasing the cure rate, reducing infection recurrence and disability risk, restoring limb function and improving quality of life of the patient.


Asunto(s)
Consenso , Fijación de Fractura/efectos adversos , Fracturas Óseas/cirugía , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones de los Tejidos Blandos/diagnóstico , Infección de la Herida Quirúrgica/diagnóstico , Cicatrización de Heridas/fisiología , Antibacterianos/uso terapéutico , Biopelículas , China , Desbridamiento/métodos , Fracturas Óseas/complicaciones , Humanos , Guías de Práctica Clínica como Asunto , Infecciones Relacionadas con Prótesis/terapia , Procedimientos de Cirugía Plástica/métodos , Infecciones de los Tejidos Blandos/terapia , Infección de la Herida Quirúrgica/terapia , Rayos X
20.
Drug Des Devel Ther ; 13: 3529-3538, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31631977

RESUMEN

OBJECTIVE: Chondrocyte apoptosis has also been strongly correlated with the severity of cartilage damage and matrix depletion in an osteoarthritis (OA) joint. Therefore, pharmacological inhibitors of apoptosis may provide a novel treatment option for patients with OA. Aucubin, a natural compound isolated from Eucommia ulmoides, has been proved to possess antioxidative and anti-apoptotic properties. However, anti-osteoarthritis effect of aucubin in animal model and anti-apoptotic response of aucubin in OA chondrocytes remain unclear. This study aimed to determine whether aucubin could slow progression of OA in a mouse model and inhibit the IL-1ß-induced chondrocyte apoptosis. METHODS: OA severity and articular cartilage degradation were evaluated by Safranin-O staining, Hematoxylin-eosin (H&E) staining, and Osteoarthritis Research Society International (OARSI) standards. Chondrocyte viability was observed by Cell Counting Kit-8 (CCK8) and live/dead cells assay; the apoptotic rate of chondrocytes was evaluated by flow cytometry (FCM) with Annexin V-FITC/PI kit. Mediators of apoptosis were tested by Western blot of Bax, caspase-3, caspase-9, and Bcl-2 expression. The intracellular levels of Reactive oxygen species (ROS) were assessed by the probe of 2,7-Dichlorofluorescin diacetate (DCFH-DA). RESULTS: The articular cartilage in the limb with destabilization of the medial meniscus (DMM) exhibited early OA-like manifestations characterized by proteoglycan loss, cartilage fibrillation, and erosion, with lower OARSI score. Oral administration of aucubin remarkably attenuated the loss of proteoglycan and the articular cartilage erosion and decreased the OARSI scores underwent DMM surgery. Aucubin treatment significantly reverses IL-1ß-induced cytotoxicity and attenuated the IL-1ß-induced chondrocyte apoptosis. In addition, aucubin can significantly inhibit mediators of apoptosis in rat primary chondrocytes. Furthermore, aucubin remarkably attenuated the IL-1ß-induced intracellular ROS production. CONCLUSION: Our findings suggest that aucubin has a protective effect on articular cartilage and slowing progression of OA in a mouse model. This protective effect may result from inhibiting chondrocyte apoptosis and excessive ROS production.


Asunto(s)
Apoptosis/efectos de los fármacos , Condrocitos/efectos de los fármacos , Modelos Animales de Enfermedad , Interleucina-1beta/metabolismo , Glucósidos Iridoides/farmacología , Osteoartritis/tratamiento farmacológico , Sustancias Protectoras/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Condrocitos/metabolismo , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Ratones Endogámicos C57BL , Osteoartritis/metabolismo , Osteoartritis/patología , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
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