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1.
Biomed Mater ; 18(3)2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36808917

RESUMO

Bioemulsions are attractive platforms for the expansion of adherent cells in bioreactors. Their design relies on the self-assembly of protein nanosheets at liquid-liquid interfaces, displaying strong interfacial mechanical properties and promoting integrin-mediated cell adhesion. However, most systems developed to date have focused on fluorinated oils, which are unlikely to be accepted for direct implantation of resulting cell products for regenerative medicine, and protein nanosheets self-assembly at other interfaces has not been investigated. In this report, the composition of aliphatic pro-surfactants palmitoyl chloride and sebacoyl chloride, on the assembly kinetics of poly(L-lysine) at silicone oil interfaces and characterisation of ultimate interfacial shear mechanics and viscoelasticity is presented. The impact of the resulting nanosheets on the adhesion of mesenchymal stem cells (MSCs) is investigated via immunostaining and fluorescence microscopy, demonstrating the engagement of the classic focal adhesion-actin cytoskeleton machinery. The ability of MSCs to proliferate at the corresponding interfaces is quantified. In addition, expansion of MSCs at other non-fluorinated oil interfaces, based on mineral and plant-based oils is investigated. Finally, the proof-of-concept of such non-fluorinated oil systems for the formulation of bioemulsions supporting stem cell adhesion and expansion is demonstrated.


Assuntos
Células-Tronco Mesenquimais , Silicones , Adesão Celular , Proteínas/metabolismo , Óleos/metabolismo , Minerais/metabolismo
2.
Adv Healthc Mater ; 12(13): e2203297, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36717365

RESUMO

Stem cells are known to sense and respond to the mechanical properties of biomaterials. In turn, cells exert forces on their environment that can lead to striking changes in shape, size and contraction of associated tissues, and may result in mechanical disruption and functional failure. However, no study has so far correlated stem cell phenotype and biomaterials toughness. Indeed, disentangling toughness-mediated cell response from other mechanosensing processes has remained elusive as it is particularly challenging to uncouple Youngs' or shear moduli from toughness, within a range relevant to cell-generated forces. In this report, it is shown how the design of the macromolecular architecture of polymer nanosheets regulates interfacial toughness, independently of interfacial shear storage modulus, and how this controls the expansion of mesenchymal stem cells at liquid interfaces. The viscoelasticity and toughness of poly(l-lysine) nanosheets assembled at liquid-liquid interfaces is characterised via interfacial shear rheology. The local (microscale) mechanics of nanosheets are characterised via magnetic tweezer-assisted interfacial microrheology and the thickness of these assemblies is determined from in situ ellipsometry. Finally, the response of mesenchymal stem cells to adhesion and culture at corresponding interfaces is investigated via immunostaining and confocal microscopy.


Assuntos
Células-Tronco Mesenquimais , Nanoestruturas , Materiais Biocompatíveis/metabolismo
3.
Aging Clin Exp Res ; 33(11): 2967-2977, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33837500

RESUMO

OBJECTIVE: Despite the high incidence and mortality of cardiovascular events in hyperuricemia patients, the role of serum uric acid in cardiovascular diseases is still controversial. The aim of this meta-analysis was to explore the difference of carotid intima-media thickness in hyperuricemia and control groups. METHODS: We performed this meta-analysis by searching the PubMed, Cochrane Library, Embase and Web of Science databases up to July 2020. The 95% confidence intervals and standard mean differences were calculated to analyze the differences in carotid intima-media thickness in hyperuricemia groups and control groups. Sensitivity analysis, subgroup analysis and meta-regression were used to explore the sources of heterogeneity. Publication bias was evaluated by funnel plot and Begg's regression test. We used Stata 14.0 software to complete our analyses. RESULTS: A total of 8 articles were included. The results showed that there was a significant increase in carotid intima-media thickness in the hyperuricemia groups compared with the control groups [SMD = 0.264, 95% CI (0.161-0.366), P < 0.001]. Subgroup analyses showed that age, sample size, blood pressure and body mass index were not the source of heterogeneity. Meta-regression enrolled the method of CIMT measurement, location, age, smoking and diabetes mellitus as categorical variables, but none of these factors was found to be significant in the model. The Begg's test value (P = 0.174) was greater than 0.05, indicating there was no publication bias. CONCLUSION: The results showed that carotid intima-media thickness was increased in hyperuricemia patients compared with controls, which indicated that hyperuricemia patients may have a higher risk of cardiovascular diseases.


Assuntos
Doenças Cardiovasculares , Hiperuricemia , Pressão Sanguínea , Espessura Intima-Media Carotídea , Humanos , Hiperuricemia/complicações , Ácido Úrico
4.
Sensors (Basel) ; 21(4)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578690

RESUMO

In this paper, we propose a deep-learning-based method using a convolutional neural network (CNN) to predict the volume flow rates of individual phases in the oil-gas-water three-phase intermittent flow simultaneously by analyzing the measurement data from multiple sensors, including a temperature sensor, a pressure sensor, a Venturi tube and a microwave sensor. To build datasets, a series of experiments for the oil-gas-water three-phase intermittent flow in a horizontal pipe, in which gas volume fraction and water-in-liquid ratio ranges are 23.77-94.45% and 14.95-86.97%, respectively, and gas flow superficial velocity and liquid flow superficial velocity ranges are 0.66-5.23 and 0.27-2.14 m/s, respectively, have been carried out on a test loop pipeline. The preliminary results indicate that the model can provide relative prediction errors on the testing-1 dataset for the volume flow rates of oil-phase, gas-phase and water-phase within ±10% with 94.49%, 92.56% and 95.71% confidence levels, respectively. Additionally, the prediction results on the testing-2 dataset also demonstrate the generalization ability of the model. The consuming time of a prediction with one sample is 0.43 s on an Intel Xeon CPU E5-2678 v3, and 0.01 s on an NVIDIA GeForce GTX 1080 Ti GPU. Hence, the proposed CNN-based prediction model, which can fulfill the real-time application requirements in the petroleum industry, reveals the potential of using deep learning to obtain accurate results in the multiphase flow measurement field.

5.
Clin Rheumatol ; 40(4): 1283-1289, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32939570

RESUMO

OBJECTIVES: The relationship between rheumatoid arthritis (RA) and the risk of leukemia was still controversial. This study aimed to assess the risk of leukemia in patients with rheumatoid arthritis by systematic review and meta-analysis. METHODS: Relevant studies were identified by searching PubMed, Embase, Cochrane Library, and SinoMed up to December 2019. Random effects model analysis was used to pool standardized incidence ratios (SIRs) and 95% confidence interval. RESULTS: A total of 15 relevant studies that met the criteria were included. Compared with the general population, patients with RA showed an increased risk of leukemia (SIR = 1.51, 95% CI: 1.34-1.70). The statistical heterogeneity was moderate with an I2 of 55.5%. In subgroup analysis, the source of heterogeneity may be due to differences in sample size. Publication bias was not found in the Begg funnel plot and the Egger test. CONCLUSION: Our findings suggested that the risk of leukemia in RA was increased compared with the general population. Key points • This is the first systematic review and meta-analysis to assess the risk of leukemia in RA. • Our study suggested that the risk of leukemia in RA was increased compared with the general population. • This study indicated that the risk of leukemia in RA was higher in non-Asian populations.


Assuntos
Artrite Reumatoide , Leucemia , Artrite Reumatoide/complicações , Artrite Reumatoide/epidemiologia , Humanos , Incidência , Leucemia/complicações , Leucemia/epidemiologia
6.
Biomater Sci ; 8(12): 3430-3442, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32406432

RESUMO

The pathogenesis of rheumatoid arthritis (RA) is related to the inhibition of osteoblast differentiation. Exosomes secreted from RA fibroblast-like synoviocytes (RA-FLSs-exos) are associated with the pathogenesis of RA and microRNAs (miRNAs) being crucial for RA progression. Accordingly, the aim of the present study is to elucidate the effect of RA-FLS-derived exosomes on osteoblast differentiation and further identify exosomal cargos responsible for this effect. RA-FLSs were isolated from a RA patient and osteoblasts from the donor bone. Isolated RA-FLSs-exos were co-cultured with osteoblasts. Osteoblast differentiation was evaluated by ALP quantification assays, Alizarin Red S staining, and determining markers of osteoblast activity (Osx, OC, Col1a1 and Dlx2). Collagen induced arthritis (CIA)-induced mouse models were established. RA-FLSs-exo could be phagocytosed by osteoblasts. Elevating the expression of miR-486-5p in RA-FLSs-exo promoted osteoblast differentiation. miR-486-5p targeted Tob1 and activated the BMP/Smad signaling pathway in osteoblasts. In addition, RA-FLSs-exo containing miR-486-5p facilitated osteoblast differentiation by activating the BMP/Smad signaling pathway and repressing Tob1. Moreover, RA-FLSs-exo containing miR-486-5p alleviated the disease severity of RA by decreasing Tob1 expression in CIA-induced mice. To sum up, RA-FLSs-exo carrying miR-486-5p serve as a promoter for osteoblast differentiation in RA, ultimately highlighting a promising competitive new target for RA treatment.


Assuntos
Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Proteína Morfogenética Óssea 2/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MicroRNAs , Osteoblastos/citologia , Proteínas Smad/metabolismo , Sinoviócitos/citologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Artrite Experimental/genética , Artrite Experimental/metabolismo , Proteína Morfogenética Óssea 2/genética , Diferenciação Celular , Células Cultivadas , Exossomos , Fibroblastos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos Endogâmicos DBA , Transdução de Sinais , Sinoviócitos/metabolismo , Proteínas Supressoras de Tumor/genética
7.
ACS Nano ; 12(9): 9206-9213, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30178996

RESUMO

The culture of adherent cells is overwhelmingly relying on the use of solid substrates to support cell adhesion. Indeed, it is typically thought that relatively strong bulk mechanical properties (bulk moduli in the range of kPa to GPa) are essential to promote cell adhesion and, in turn, regulate cell expansion and fate decision. In this report, we show that adherent stem cells such as mesenchymal stem cells and primary keratinocytes can be cultured at the surface of liquid substrates and that this phenomenon is mediated by the assembly of polymer nanosheets at the liquid-liquid interface. We use interfacial rheology to quantify this assembly and demonstrate the strong mechanical properties of such nanosheets. Importantly, we show that cell adhesion to such quasi-2D materials is mediated by the classical integrin/acto-myosin machinery, despite the absence of bulk mechanical properties of the underlying liquid substrate. Finally, we show that stem cell proliferation and fate decision are also regulated by the mechanical properties of these self-assembled protein nanosheets. Liquid substrates offer attractive features for the culture of adherent cells and stem cells, and the development of novel stem cell technologies, such as liquid-liquid systems, are particularly well-adapted to automated parallel processing and scale up.


Assuntos
Queratinócitos/citologia , Células-Tronco Mesenquimais/citologia , Nanoestruturas/química , Polímeros/química , Proliferação de Células , Células Cultivadas , Humanos , Tamanho da Partícula , Reologia , Propriedades de Superfície
8.
Sci Rep ; 8(1): 2479, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29410500

RESUMO

HLA-haploidentical hematopoietic stem cell transplantation (HSCT) may be an option for severe aplastic anemia (SAA) patients. However, to date, no large-sample studies have been performed to determine which types of SAA patients are suitable for HLA-haploidentical HSCT. We retrospectively studied 189 consecutive patients with SAA who underwent HLA-identical or HLA-haploidentical HSCT at seven transplant centers in China. Propensity score matching (PSM) was applied in this study to reduce the influence of potential confounders. The 5-year overall survival (OS) rate was 72.0% in the HLA-haploidentical group and 76.5% in the HLA-identical group. The median time to achieve engraftment and the incidence of acute GVHD/chronic GVHD were not significantly different between the two groups. In the subgroup analysis, the outcome of patients older than 40 years in the HLA-haploidentical group was significantly poorer than that of patients younger than 40 years in the same group and that of patients older than 40 years in the HLA-identical group. Based on the above results, we suggest that HLA-haploidentical relative HSCT should be considered as a valid alternative option for patients younger than 40 years with SAA for whom no matched sibling donor is available.


Assuntos
Anemia Aplástica/terapia , Doença Enxerto-Hospedeiro/diagnóstico , Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas/métodos , Doença Aguda , Adolescente , Adulto , Anemia Aplástica/imunologia , Anemia Aplástica/mortalidade , Anemia Aplástica/patologia , Criança , Pré-Escolar , China , Doença Crônica , Feminino , Expressão Gênica , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/patologia , Antígenos HLA/genética , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Retrospectivos , Tamanho da Amostra , Índice de Gravidade de Doença , Análise de Sobrevida , Doadores de Tecidos/classificação , Transplante Haploidêntico
9.
Leuk Res ; 38(9): 1048-54, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25052306

RESUMO

Novel agents thalidomide and bortezomib have significantly improved myeloma treatment. However, it remains unclear whether patients will benefit more from the combination therapy of these two agents. Our meta-analysis aims to compare the efficiency, and more importantly, the safety of bortezomib-thalidomide-based (VT-based) versus bortezomib-based or thalidomide-based (V-based/T-based) regimens as induction therapy in patients with previously untreated myeloma. Overall, five phase III RCTs including 1765 patients were identified. Compared with V-based or T-based regimens, VT-based regimens significantly improved CR (OR=2.22, 95% CI [1.44, 3.43]), ORR (OR=2.19, 95% CI [1.51, 3.19]) as well as PFS (HR=0.69, 95% CI [0.54, 0.88]), but not OS (HR=1.04, 95% CI [0.91, 1.19]). Notably, most expected side effects of bortezomib or thalidomide were comparable in both groups, including hematologic (anemia, neutropenia, thrombocytopenia), nonhematologic (peripheral neuropathy, deep venous thrombosis, infections, gastrointestinal events) side effects and discontinuation during or after induction therapy. These results suggest that combination of thalidomide and bortezomib might be a better first-line choice for patients with untreated myeloma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ácidos Borônicos/administração & dosagem , Ácidos Borônicos/efeitos adversos , Quimioterapia de Indução/métodos , Mieloma Múltiplo/tratamento farmacológico , Pirazinas/administração & dosagem , Pirazinas/efeitos adversos , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Bortezomib , Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Humanos , Quimioterapia de Indução/efeitos adversos , Mieloma Múltiplo/mortalidade , Terapia Neoadjuvante , Neutropenia/induzido quimicamente , Neutropenia/epidemiologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Análise de Sobrevida , Resultado do Tratamento
10.
Clin Transplant ; 27(2): E109-15, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23387380

RESUMO

We have developed a practical conditioning regimen without anti-thymocyte globulin (ATG), irradiation, or other myeloablative alkylating agent for low-income countries in which patients with severe aplastic anemia (SAA), who usually have heavily transfused and a prolonged disease history. The application of ATG, Busulphan, and/or irradiation to cyclophosphamide (Cy) to avoid graft rejection has many short- and long-term complications. In this study, we focused on evaluating a fludarabine-based conditioning regimen, among 83 patients with SAA. Patients were treated with fludarabine (40 mg/m(2) /d; day [-5 to -2]) and cyclophosphamide (50 mg/kg/d; day [-5 to -2]). Altogether, 81 patients indicated initial engraftment, whereas two cases showed primary graft failure. And four of the 81 cases indicated graft rejection during follow-up. Regardless of a high cumulative incidence of acute (55/83; 66.2% grade II-IV; 47/83; 56.6% III-IV) and chronic graft-versus-host disease (50/83; 60.2%), in total, 77 patients showed durable engraftment and transfusion independence, and 64 are alive at a median time of 49 months with an overall survival rate of 66%. In conclusion, this conditioning indicated well toleration, mild toxicity, durable engraftment, excellent survival as well as less cost. Its application might shed new light on SAA at high risk of graft rejection in resource-limited countries.


Assuntos
Anemia Aplástica/cirurgia , Ciclofosfamida/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Agonistas Mieloablativos/uso terapêutico , Condicionamento Pré-Transplante/métodos , Vidarabina/análogos & derivados , Adolescente , Adulto , Anemia Aplástica/mortalidade , Anemia Aplástica/terapia , Criança , Pré-Escolar , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Rejeição de Enxerto/prevenção & controle , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Estimativa de Kaplan-Meier , Masculino , Taxa de Sobrevida , Resultado do Tratamento , Vidarabina/uso terapêutico , Adulto Jovem
11.
Zhonghua Xue Ye Xue Za Zhi ; 32(12): 844-7, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22339959

RESUMO

OBJECTIVE: To evaluate the feasibility of HLA haploidentical peripheral blood hematopoietic stem cell transplantation (PBSCT) for patients with ß thalassemia major. METHODS: Sixteen patients with ß thalassemia major received HLA haploidentical PBSCT from parents. Two conditioning regimens were used. Regimen A was adopted before December 2007, which consisted of fludarabine (total 150 mg/m²), busulfex (total 520 mg/m²), cyclophosphamide (CTX, total 100 mg/kg), antithymocyte globulin (ATG, total 10 mg/kg) and total body irradiation of 3 Gy. Regimen B was adopted after December 2007, which consisted of fludarabine (total 240 mg/m²), busulfex (total 520 mg/m²), CTX (total 100 mg/kg), and ATG (total 10 mg/kg). Combination of cyclosporin (CsA), methotrexate (MTX) and mycophenolate mofetil (MMF) were used for prophylaxis of graft-versus-host disease (GVHD). RESULTS: Of 16 patients, 14 (87.5%) had sustained engraftment. The median days of neutrophil exceeding 0.5 × 109/L and platelet exceeding 20 × 109/L were 13 days (range 10 - 17 days) and 15 days (range 14 - 20 days) after PBSCT, respectively. Complete chimerism was achieved in all the 14 patients at one month after PBSCT. One patient lost his graft with autologous reconstitution 52 days after transplantation. Four patients had grade II-IV acute GVHD and one patient had chronic extensive GVHD. In the 49-month median follow-up duration, 13 of 16 patients were alive in disease-free situation. CONCLUSION: HLA haploidentical PBSCT, which could provide stable and sustained engraftment for thalassemia major patients with no HLA identical donor, is a promising treatment strategy.


Assuntos
Antígenos HLA/genética , Transplante de Células-Tronco de Sangue Periférico , Talassemia beta/terapia , Criança , Pré-Escolar , Feminino , Haploidia , Humanos , Masculino , Doadores de Tecidos
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