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1.
Sleep Biol Rhythms ; 21(2): 233-240, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38469290

RESUMO

This study aimed to investigate the alterations in limbic structure volumes and limbic covariance network in patients with isolated rapid eye movement (REM) sleep behavior disorder (iRBD) and to compare them with healthy controls. We retrospectively enrolled 35 patients with iRBD and 35 healthy controls who underwent three-dimensional T1-weighted brain MRI. Volumetric analysis of subcortical limbic structures, including the hippocampus, amygdala, thalamus, mammillary body, hypothalamus, basal forebrain, septal nuclei, fornix, and nucleus accumbens, was performed. Furthermore, the limbic covariance network was examined using graph theory based on the limbic structure volumes. Some of the limbic structure volumes differed significantly. The right amygdala and hypothalamus volumes were lower in the patients with iRBD than in the healthy controls (0.101% vs. 0.114%, p = 0.016, and 0.027% vs. 0.030%, p = 0.045, respectively). However, there were no significant differences in the limbic covariance network between the groups. This study demonstrated that the volumes of the right amygdala and hypothalamus are lower in patients with iRBD, even without cognitive impairments, than in healthy controls. However, there were no significant differences in the limbic covariance network between the groups. The involvements of the limbic structures could be related to the conversion to neurodegenerative diseases in patients with iRBD.

2.
Med Sci Sports Exerc ; 50(12): 2451-2458, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30102674

RESUMO

PURPOSE: This study aimed at investigating whether there is a continuous dose-response relationship between the amount of physical activity (PA) and longevity benefit. METHODS: We evaluated the records of 23,257,723 Koreans age ≥20 yr who had undergone one biennial medical evaluation by the National Health Insurance Corporation. Participants with ≥20 min of vigorous or ≥30 min of moderate PA or walking were stratified into four groups: 0 d·wk; 1-3 d·wk; 4 to 5 d·wk; and 6-7 d·wk. After calculating total metabolic equivalent task-hours per week (MET·h·wk), we created eight categories of MET-hours per week (0, 0.1-4.9, 5.0-9.9, 10.0-14.9, 15.0-19.9, 20.0-24.9, 25.0-29.9, and ≥30.0). Multivariate Cox proportional hazard analyses were performed. RESULTS: A reverse J-shaped risk curve was observed, with the lowest mortality risk in the participants exercising 4 to 5 d·wk (reference). Participants who did not exercise at all and those who exercised with a PA frequency of 1 to 3 d·wk or 6 to 7 d·wk showed a significantly increased mortality risk compared with the reference group. When we repeated the Cox analysis among the 8 MET·h·wk categories with the participants reporting 20.0 to 24.9 MET·h·wk of PA as the reference group, we found that those with physical inactivity and 25.0-29.9 or ≥30.0 MET·h·wk of PA showed a higher mortality risk than the reference group. These relationships were persistently observed after adjustment for confounders. CONCLUSIONS: An appropriate amount of regular exercise in each specific type of PA was associated with the lowest risk of mortality. The inactive participants showed an increased mortality risk, and daily PA did not show any additional benefit in the mortality risk.


Assuntos
Exercício Físico , Longevidade , Mortalidade , Comportamento de Redução do Risco , Adulto , Idoso , Feminino , Humanos , Masculino , Equivalente Metabólico , Pessoa de Meia-Idade , República da Coreia , Inquéritos e Questionários , Caminhada
3.
J Biomed Inform ; 67: 11-20, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28163197

RESUMO

For each cancer type, only a few genes are informative. Due to the so-called 'curse of dimensionality' problem, the gene selection task remains a challenge. To overcome this problem, we propose a two-stage gene selection method called MRMR-COA-HS. In the first stage, the minimum redundancy and maximum relevance (MRMR) feature selection is used to select a subset of relevant genes. The selected genes are then fed into a wrapper setup that combines a new algorithm, COA-HS, using the support vector machine as a classifier. The method was applied to four microarray datasets, and the performance was assessed by the leave one out cross-validation method. Comparative performance assessment of the proposed method with other evolutionary algorithms suggested that the proposed algorithm significantly outperforms other methods in selecting a fewer number of genes while maintaining the highest classification accuracy. The functions of the selected genes were further investigated, and it was confirmed that the selected genes are biologically relevant to each cancer type.


Assuntos
Algoritmos , Perfilação da Expressão Gênica , Neoplasias/genética , Máquina de Vetores de Suporte , Técnicas Genéticas , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
4.
J Tissue Eng Regen Med ; 11(8): 2286-2294, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-26799635

RESUMO

Monolayer culture is integral to many cell-based cartilage repair strategies, but chondrocytes lose regenerative potential with increasing duration in vitro. This coincides with elevated reactive oxygen species (ROS) levels and a bioenergetic transformation characterized by increasing mitochondrial function. This study investigates ROS as stimuli for bioenergetic reprogramming and the effect of antioxidants on the propensity of chondrocytes to regenerate a cartilaginous matrix. Articular chondrocytes were cultured in monolayer under a 2% O2 atmosphere. Oxidative stress was increased using 50 µm H2 O2 or a 20% O2 culture atmosphere, or decreased using the antioxidant N-acetyl-cysteine (NAC). Mitochondrial function was characterized using 200 nm Mitotracker green and an oxygen biosensor. After two population doublings ± NAC, chondrocytes were encapsulated in alginate beads (1 × 107 cells/ml) for an additional 10 days before DMB assay of glycosaminoglycan content. The beads were cultured under both 20% O2 and the more physiological 5% O2 condition. Chondrocytes expanded in 20% O2 exhibited elevated mitochondrial mass and functional capacity, which was partially mimicked by the exogenous ROS, H2 O2 . Oligomycin treatment revealed that the increased oxygen consumption was coupled to oxidative phosphorylation. NAC limited these markers of bioenergetic reprogramming during culture-expansion with no significant effect on subsequent GAG production under 20% O2 . However, NAC treatment in monolayer abolished the hypoxic induction of GAG in alginate beads. This supports the hypothesis of a causal relationship between exposure to ROS and acquired mitochondrial function in chondrocytes. Additionally, mitochondrial function may be required for the hypoxic induction of GAG synthesis by chondrocytes. © 2015 The Authors. Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons, Ltd.


Assuntos
Cartilagem Articular , Técnicas de Reprogramação Celular , Condrócitos , Metabolismo Energético , Espécies Reativas de Oxigênio , Animais , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Bovinos , Hipóxia Celular/efeitos dos fármacos , Condrócitos/citologia , Condrócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/farmacologia
5.
Inflamm Res ; 66(1): 49-58, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27658702

RESUMO

OBJECTIVE AND DESIGN: Oxygen tension and biomechanical signals are factors that regulate inflammatory mechanisms in chondrocytes. We examined whether low oxygen tension influenced the cells response to TNFα and dynamic compression. MATERIALS AND METHODS: Chondrocyte/agarose constructs were treated with varying concentrations of TNFα (0.1-100 ng/ml) and cultured at 5 and 21 % oxygen tension for 48 h. In separate experiments, constructs were subjected to dynamic compression (15 %) and treated with TNFα (10 ng/ml) and/or L-NIO (1 mM) at 5 and 21 % oxygen tension using an ex vivo bioreactor for 48 h. Markers for catabolic activity (NO, PGE2) and tissue remodelling (GAG, MMPs) were quantified by biochemical assay. ADAMTS-5 and MMP-13 expression were examined by real-time qPCR. 2-way ANOVA and a post hoc Bonferroni-corrected t test were used to analyse data. RESULTS: TNFα dose-dependently increased NO, PGE2 and MMP activity (all p < 0.001) and induced MMP-13 (p < 0.05) and ADAMTS-5 gene expression (pp < 0.01) with values greater at 5 % oxygen tension than 21 %. The induction of catabolic mediators by TNFα was reduced by dynamic compression and/or L-NIO (all p < 0.001), with a greater inhibition observed at 5% than 21 %. The stimulation of GAG synthesis by dynamic compression was greater at 21 % than 5 % oxygen tension and this response was reduced with TNFα or reversed with L-NIO. CONCLUSIONS: The present findings revealed that TNFα increased production of NO, PGE2 and MMP activity at 5 % oxygen tension. The effects induced by TNFα were reduced by dynamic compression and/or the NOS inhibitor, linking both types of stimuli to reparative activities. Future therapeutics should develop oxygen-sensitive antagonists which are directed to interfering with the TNFα-induced pathways.


Assuntos
Condrócitos/efeitos dos fármacos , Oxigênio/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Proteína ADAMTS5/genética , Animais , Bovinos , Células Cultivadas , Condrócitos/metabolismo , Condrócitos/fisiologia , Dinoprostona/metabolismo , Glicosaminoglicanos/metabolismo , Metaloproteinase 13 da Matriz/genética , Óxido Nítrico/metabolismo , Estresse Mecânico
6.
Oncoimmunology ; 5(4): e1115178, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27141397

RESUMO

Natural killer (NK) cells are increasingly used in clinical studies in order to treat patients with various malignancies. The following review summarizes platform lectures and 2013-2015 consortium meetings on manufacturing and clinical use of NK cells in Europe and United States. A broad overview of recent pre-clinical and clinical results in NK cell therapies is provided based on unstimulated, cytokine-activated, as well as genetically engineered NK cells using chimeric antigen receptors (CAR). Differences in donor selection, manufacturing and quality control of NK cells for cancer immunotherapies are described and basic recommendations are outlined for harmonization in future NK cell studies.

7.
Osteoarthritis Cartilage ; 24(5): 912-20, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26706702

RESUMO

OBJECTIVE: Chondrocyte dedifferentiation is known to influence cell mechanics leading to alterations in cell function. This study examined the influence of chondrocyte dedifferentiation in monolayer on cell viscoelastic properties and associated changes in actin organisation, bleb formation and membrane-actin cortex interaction. METHOD: Micropipette aspiration was used to estimate the viscoelastic properties of freshly isolated articular chondrocytes and the same cells after passage in monolayer. Studies quantified the cell membrane-actin cortex adhesion by measuring the critical pressure required for membrane detachment and bleb formation. We then examined the expression of ezrin, radixin and moesin (ERM) proteins which are involved in linking the membrane and actin cortex and combined this with theoretical modelling of bleb dynamics. RESULTS: Dedifferentiated chondrocytes at passage 1 (P1) were found to be stiffer compared to freshly isolated chondrocytes (P0), with equilibrium modulus values of 0.40 and 0.16 kPa respectively. The critical pressure increased from 0.59 kPa at P0 to 0.74 kPa at P1. Dedifferentiated cells at P1 exhibited increased cortical F-actin organisation and increased expression of total and phosphorylated ERM proteins compared to cells at P0. Theoretical modelling confirmed the importance of membrane-actin cortex adhesion in regulating bleb formation and effective cellular elastic modulus. CONCLUSION: This study demonstrates that chondrocyte dedifferentiation in monolayer strengthens membrane-actin cortex adhesion associated with increased F-actin organisation and up-regulation of ERM protein expression. Thus dedifferentiated cells have reduced susceptibility to bleb formation which increases cell modulus and may also regulate other fundamental aspects of cell function such as mechanotransduction and migration.


Assuntos
Actinas/metabolismo , Desdiferenciação Celular/fisiologia , Membrana Celular/metabolismo , Condrócitos/citologia , Animais , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Bovinos , Adesão Celular/fisiologia , Células Cultivadas , Condrócitos/metabolismo , Condrócitos/fisiologia , Proteínas do Citoesqueleto/metabolismo , Elasticidade , Masculino , Mecanotransdução Celular/fisiologia , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Regulação para Cima/fisiologia , Viscosidade
8.
Bone Marrow Transplant ; 51(1): 27-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26367220

RESUMO

Cord blood (CB) transplantation is an alternate source of human hematopoietic progenitor cells for allogeneic stem cell transplantation in children and adolescents with both malignant and nonmalignant diseases. Current limitations included delay in hematopoietic reconstitution, increased incidence of primary graft failure and slow cellular immunoreconstitution. These limitations lead to a significant increase in primary graft failure, infectious complications and increased transplant-related mortality. There is a number of experimental approaches currently under investigation including cellular engineering to circumvent these limitations. In this review, we summarize the recent findings of utilizing ex vivo CB expansion with Notch1 ligand Delta 1, mesenchymal progenitor cells, the use of human placenta-derived stem cells and CB-derived natural killer cells. Early and preliminary results suggest some of these experimental cellular strategies may in part ameliorate the incidence of primary graft failure, delays in hematopoietic reconstitution and/or slowness in cellular immune reconstitution following unrelated CB transplantation.


Assuntos
Engenharia Celular/métodos , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Rejeição de Enxerto/terapia , Recuperação de Função Fisiológica , Adolescente , Aloenxertos , Criança , Pré-Escolar , Feminino , Rejeição de Enxerto/metabolismo , Humanos , Lactente , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/transplante , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Placenta/metabolismo , Gravidez
9.
Clin Exp Immunol ; 172(1): 104-12, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23480190

RESUMO

Natural killer (NK) cell adoptive transfer is a promising approach for cancer immunotherapy; however, its development has been hindered by the lack of efficient methods to produce large numbers of functional NK cells. In this study, we engineered the leukaemia cell line K562 to express CD137 ligand (CD137L) and membrane-bound interleukin (mbIL)-21 on the cell surface, and used these cells to expand NK cells from the peripheral blood mononuclear cells. We found that purity of the NK cells (CD3(-) CD56(+) /CD16(+) ) increased from less than 30% to above 95% after a 3-week expansion and proliferation of the cells was sustained for more than 8 weeks. The surface expression of NK cell activating and inhibitory receptors, except for NKp80, was clearly increased with the expansion, and NK cell-mediated killing activity was also enhanced significantly. However, these changes in both phenotype and function were clearly reversed by JSI-124, a specific signal transducer and activator of transcription-3 (STAT-3) inhibitor. Taken together, data showed that the combination of mbIL-21 and CD137L could efficiently induce the formation of functional human NK cells from peripheral blood mononuclear cells, and STAT-3 inhibition could impair this induction. Therefore, STAT-3 activation may benefit human NK cell proliferation and cytotoxicity, and provide valuable clinical applications in NK cell immunotherapy against viral infectious diseases and cancers.


Assuntos
Ligante 4-1BB/imunologia , Interleucinas/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Fator de Transcrição STAT3/agonistas , Ligante 4-1BB/genética , Comunicação Celular/efeitos dos fármacos , Engenharia Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Expressão Gênica/efeitos dos fármacos , Humanos , Interleucinas/genética , Células K562 , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Ligação Proteica , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Transdução de Sinais/efeitos dos fármacos , Triterpenos/farmacologia
10.
Biophys J ; 103(6): 1188-97, 2012 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-22995491

RESUMO

This study adopts a combined computational and experimental approach to determine the mechanical, structural, and metabolic properties of isolated chondrocytes cultured within three-dimensional hydrogels. A series of linear elastic and hyperelastic finite-element models demonstrated that chondrocytes cultured for 24 h in gels for which the relaxation modulus is <5 kPa exhibit a cellular Young's modulus of ∼5 kPa. This is notably greater than that reported for isolated chondrocytes in suspension. The increase in cell modulus occurs over a 24-h period and is associated with an increase in the organization of the cortical actin cytoskeleton, which is known to regulate cell mechanics. However, there was a reduction in chromatin condensation, suggesting that changes in the nucleus mechanics may not be involved. Comparison of cells in 1% and 3% agarose showed that cells in the stiffer gels rapidly develop a higher Young's modulus of ∼20 kPa, sixfold greater than that observed in the softer gels. This was associated with higher levels of actin organization and chromatin condensation, but only after 24 h in culture. Further studies revealed that cells in stiffer gels synthesize less extracellular matrix over a 28-day culture period. Hence, this study demonstrates that the properties of the three-dimensional microenvironment regulate the mechanical, structural, and metabolic properties of living cells.


Assuntos
Microambiente Celular , Análise de Elementos Finitos , Fenômenos Mecânicos , Citoesqueleto de Actina/metabolismo , Fenômenos Biomecânicos , Núcleo Celular/metabolismo , Condrócitos/citologia , Cromatina/metabolismo , Elasticidade , Matriz Extracelular/metabolismo
11.
J Mech Behav Biomed Mater ; 11: 72-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22658156

RESUMO

Physical stimuli play a crucial role in skeletogenesis and osteochondral repair and regeneration. Although the periosteum and periosteum-derived cells offer considerable therapeutic potential, the molecular mechanisms that control their differentiation are still not fully understood. As an initial case study, this work explores the hypothesis that dynamic compression might selectively enhance chondrogenic and/or osteogenic differentiation in human periosteal cells from two donors. Donor derived human periosteal cells were expanded in monolayer culture before seeding in 3% (w/v) agarose constructs. The ability of this in vitro culture model to support cell viability, chondrogenesis, and mechanotransduction was optimised. The time course of early chondrogenic differentiation was assessed by real time RT-PCR of mRNA expression levels for bone and cartilage specific gene markers. Intermittent dynamic compression (1 Hz, 15% strain) was applied to constructs, in the presence or absence of 10 ng/ml TGF-ß3, for up to 4 days. The combined effect of TGF-ß3 and compressive loading on the expression levels of the Sox-9, Runx-2, ALP, Collagen X, and collagen type I genes was donor dependent. A synergistic effect was noted only in donor two, with peak mRNA expression levels at 24 h, particularly Sox-9 which increased 59.0-fold. These findings suggest that the interactions between mechanical stimuli and TGF-ß signalling may be an important mechanotransduction pathway for human periosteal cells and that, importantly, this cellular mechanosensitivity varies between donors.


Assuntos
Condrogênese/genética , Força Compressiva , Periósteo/citologia , Estresse Mecânico , Transcriptoma , Adulto , Cápsulas , Condrogênese/efeitos dos fármacos , Humanos , Masculino , Periósteo/efeitos dos fármacos , Periósteo/metabolismo , Sefarose/farmacologia , Fatores de Tempo , Transcriptoma/efeitos dos fármacos , Fator de Crescimento Transformador beta3/farmacologia
12.
J Hand Surg Eur Vol ; 37(6): 555-63, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22170243

RESUMO

The mechanics of adhesions at a local tissue level have not been extensively studied. This study compared microstrains and macrostrains in adhesions of immobilized and mobilized partially lacerated flexor digitorum profundus tendons in a New Zealand White rabbit model. At 2 weeks, 50 digits were randomized to either gross tensile testing or micromechanical assessment, in which the movement of fluorescently labelled cell nuclei, acting as dynamic markers, was visualized using real-time confocal microscopy. The structural stiffness and load at failure of immobilized adhesions were 140% and 160% of that of mobilized adhesions, respectively, and both differences were statistically significant. Micromechanically, different patterns of loading and failure were observed. Mobilized adhesions exhibited over a three-fold higher local strain, which was less uniformly distributed. Confocal microscopy provided an accurate measure of local strain. For the first time, it has been possible to visualize, define, and quantify local adhesion tissue mechanics. Mobilization appears to favour the formation of sites expressing increased local strain responses or those predisposed to heterogeneity and localized failure.


Assuntos
Lacerações/fisiopatologia , Traumatismos dos Tendões/fisiopatologia , Animais , Processamento de Imagem Assistida por Computador , Imobilização , Microscopia Confocal , Coelhos , Estresse Mecânico , Aderências Teciduais/fisiopatologia
13.
J Hand Surg Eur Vol ; 37(6): 564-72, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22095400

RESUMO

This study investigated the attachment of intrinsic and extrinsic, mobilized and immobilized adhesion cells to the extracellular matrix. Five New Zealand White rabbit forepaws were dissected to isolate the flexor tendon core, tendon surface and synovial sheath, which were explanted separately. A further 10 animals were subjected to flexor tendon injuries, randomized to either mobilization or immobilization, and adhesions were explanted at 2 weeks. Cell groups were tested for attachment to collagen type-I or fibronectin and morphometric analysis was made. The attachment of intrinsic tendon cells and adhesion cells from mobilized tendons to both matrix proteins was statistically significantly greater than that of extrinsic tendon cells and adhesion cells from immobilized tendons. Adhesion cells from mobilized tendons were statistically significantly more elongated, which may correlate with the deposition of a more organized matrix. Because the synovial sheath cells were least attached to matrix proteins, selective treatments that reduce cell attachment may be used to exclude them, without inhibiting intrinsic tendon healing.


Assuntos
Colágeno/fisiologia , Matriz Extracelular/fisiologia , Fibronectinas/fisiologia , Animais , Adesão Celular/fisiologia , Células Cultivadas , Fibroblastos/citologia , Imobilização , Coelhos , Traumatismos dos Tendões
14.
Proc Inst Mech Eng H ; 225(8): 821-30, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21922958

RESUMO

Aortic valve interstitial cells are responsible for maintaining the valve in response to their local mechanical environment. However, the complex organization of the extracellular matrix means cell strains cannot be directly derived from gross strains, and knowledge of tissue structure-function correlations is fundamental towards understanding mechanotransduction. This study investigates strain transfer through the valve, hypothesizing that organization of the valve matrix leads to non-homogenous local strains. Radial and circumferential samples were cut from aortic valve leaflets and subjected to quasi-static mechanical characterization. Further samples were imaged using confocal microscopy, to determine local strains in the matrix. Mechanical data demonstrated that the valve was significantly stronger and stiffer when loaded circumferentially, comparable with previous studies. Micromechanical studies demonstrated that strain transfer through the matrix is anisotropic and indirect, with local strains consistently smaller than applied strains in both orientations. Under radial loading, strains were transferred linearly to cells. However, under circumferential loading, strains were only one-third of applied values, with a less direct relationship between applied and local strains. This may result from matrix reorganization, and be important for preventing cellular damage during normal valve function. These findings should be taken into account when investigating interstitial cell behaviours, such as cell metabolism and mechanotransduction.


Assuntos
Valva Aórtica/fisiologia , Bioprótese , Matriz Extracelular/fisiologia , Próteses Valvulares Cardíacas , Mecanotransdução Celular/fisiologia , Animais , Fenômenos Biomecânicos , Elasticidade , Feminino , Microscopia Confocal , Estimulação Física , Resistência ao Cisalhamento , Estresse Mecânico , Suínos , Resistência à Tração/fisiologia
15.
Gene Ther ; 18(9): 849-56, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21451576

RESUMO

Sleeping Beauty (SB3) transposon and transposase constitute a DNA plasmid system used for therapeutic human cell genetic engineering. Here we report a comparison of SB100X, a newly developed hyperactive SB transposase, to a previous generation SB11 transposase to achieve stable expression of a CD19-specific chimeric antigen receptor (CAR3) in primary human T cells. The electro-transfer of SB100X expressed from a DNA plasmid or as an introduced mRNA species had superior transposase activity in T cells based on the measurement of excision circles released after transposition and emergence of CAR expression on T cells selectively propagated upon CD19+ artificial antigen-presenting cells. Given that T cells modified with SB100X and SB11 integrate on average one copy of the CAR transposon in each T-cell genome, the improved transposition mediated by SB100X apparently leads to an augmented founder effect of electroporated T cells with durable integration of CAR. In aggregate, SB100X improves SB transposition in primary human T cells and can be titrated with an SB transposon plasmid to improve the generation of CD19-specific CAR+ T cells.


Assuntos
Antígenos CD19/metabolismo , Técnicas de Transferência de Genes , Receptores de Antígenos/metabolismo , Linfócitos T/metabolismo , Transposases/genética , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Eletroporação , Humanos , Neoplasias/imunologia , RNA Mensageiro , Receptores de Antígenos/genética
16.
J Biomed Mater Res B Appl Biomater ; 96(1): 110-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21061362

RESUMO

Scaffolds for tissue engineering require the correct biochemical cues if the seeded cells are to migrate into the scaffold and proliferate. For complex tissues this would require precise patterning of the scaffold structure with the particular biochemical cue required at each location on the scaffold. Electrospray enables the deposition of a wide number of biomolecules onto surfaces and can be used for precise patterning. We assessed the functionality of a key cell-adhesion molecule, fibronectin, after depositing it onto a surface using the electrospray technique. The addition of polypropylene glycol allowed a stable spray to be obtained from solutions with a range of fibronectin concentrations. Immunoassay tests showed that the amount of fibronectin retained on the surface was proportional to that sprayed from the solution. Increasing the surface density of fibronectin deposited onto silicon surfaces enhanced fibroblast attachment. The fibronectin thus appears to have retained its cell attachment functionality after undergoing the electrospray process. Since recent advances allow electrospray to pattern material from solution with micrometre accuracy this may allow materials to be biologically functionalized on a similar scale.


Assuntos
Materiais Revestidos Biocompatíveis/química , Fibroblastos/citologia , Fibronectinas/química , Teste de Materiais , Silício/química , Alicerces Teciduais/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Técnicas Eletroquímicas/métodos , Fibronectinas/farmacologia , Humanos , Silício/farmacologia
17.
Rev Sci Instrum ; 81(2): 02A721, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192390

RESUMO

The aim of the front end test stand (FETS) project is to demonstrate that chopped low energy beams of high quality can be produced. FETS consists of a 60 mA Penning Surface Plasma Ion Source, a three solenoid low energy beam transport, a 3 MeV radio frequency quadrupole, a chopper, and a comprehensive suite of diagnostics. This paper details the design and initial performance of the ion source and the laser profile measurement system. Beam current, profile, and emittance measurements are shown for different operating conditions.

18.
Rev Sci Instrum ; 81(2): 02B718, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192458

RESUMO

A front end is currently under construction consisting of a H(-) Penning ion source (65 keV, 60 mA), low energy beam transport (LEBT), and radio frequency quadrupole (3 MeV output energy) with a medium energy beam transport suitable for high power proton applications. Diagnostics can be divided either in destructive techniques such as beam profile monitor, pepperpot, slit-slit emittance scanner (preferably used during commissioning) or nondestructive, permanently installed devices such as photodetachment-based techniques. Another way to determine beam distributions is a scintillator with charge-coupled device camera. First experiments have been performed to control the beam injection into the LEBT. The influence of beam parameters such as particle energy and space-charge compensation on the two-dimensional distribution and profiles will be presented.

20.
Leukemia ; 23(8): 1490-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19262598

RESUMO

Chromosomal rearrangements of the human MLL gene are associated with high-risk pediatric, adult and therapy-associated acute leukemias. These patients need to be identified, treated appropriately and minimal residual disease was monitored by quantitative PCR techniques. Genomic DNA was isolated from individual acute leukemia patients to identify and characterize chromosomal rearrangements involving the human MLL gene. A total of 760 MLL-rearranged biopsy samples obtained from 384 pediatric and 376 adult leukemia patients were characterized at the molecular level. The distribution of MLL breakpoints for clinical subtypes (acute lymphoblastic leukemia, acute myeloid leukemia, pediatric and adult) and fused translocation partner genes (TPGs) will be presented, including novel MLL fusion genes. Combined data of our study and recently published data revealed 104 different MLL rearrangements of which 64 TPGs are now characterized on the molecular level. Nine TPGs seem to be predominantly involved in genetic recombinations of MLL: AFF1/AF4, MLLT3/AF9, MLLT1/ENL, MLLT10/AF10, MLLT4/AF6, ELL, EPS15/AF1P, MLLT6/AF17 and SEPT6, respectively. Moreover, we describe for the first time the genetic network of reciprocal MLL gene fusions deriving from complex rearrangements.


Assuntos
Leucemia/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Recombinação Genética , Translocação Genética , Doença Aguda , Adulto , Biópsia , Medula Óssea/química , Medula Óssea/patologia , Criança , Quebra Cromossômica , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 11/ultraestrutura , Biologia Computacional , DNA de Neoplasias/sangue , DNA de Neoplasias/genética , Duplicação Gênica , Histona-Lisina N-Metiltransferase , Humanos , Reação em Cadeia da Polimerase
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