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1.
Front Oncol ; 14: 1380648, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606091

RESUMO

Introduction: In monoclonal B cell lymphocytosis (MBL) and chronic lymphocytic leukemia (CLL), the expansion of malignant B cells disrupts the normal homeostasis and interactions between B cells and T cells, leading to immune dysregulation. CD20+ T cells are a subpopulation of T cells that appear to be involved in autoimmune diseases and cancer. Methods: Here, we quantified and phenotypically characterized CD20+ T cells from MBL subjects and CLL patients using flow cytometry and correlated our findings with the B-cell receptor mutational status and other features of the disease. Results and discussion: CD20+ T cells were more represented within the CD8+ T cell compartment and they showed a predominant memory Tc1 phenotype. CD20+ T cells were less represented in MBL and CLL patients vs healthy controls, particularly among those with unmutated IGVH gene. The expansion of malignant B cells was accompanied by phenotypic and functional changes in CD20+ T cells, including an increase in follicular helper CD4+ CD20+ T cells and CD20+ Tc1 cells, in addition to the expansion of the TCR Vß 5.1 in CD4+ CD20+ T cells in CLL.

2.
Animals (Basel) ; 14(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38539981

RESUMO

Traumatic nerve injuries are common lesions that affect several hundred thousand humans, as well as dogs and cats. The assessment of nerve regeneration through animal models may provide information for translational research and future therapeutic options that can be applied mutually in veterinary and human medicine, from a One Health perspective. This review offers a hands-on vision of the non-invasive and conservative approaches to peripheral nerve injury, focusing on the role of neurorehabilitation in nerve repair and regeneration. The peripheral nerve injury may lead to hypersensitivity, allodynia and hyperalgesia, with the possibility of joint contractures, decreasing functionality and impairing the quality of life. The question remains regarding how to improve nerve repair with surgical possibilities, but also considering electrical stimulation modalities by modulating sensory feedback, upregulation of BDNF, GFNF, TrKB and adenosine monophosphate, maintaining muscle mass and modulating fatigue. This could be improved by the positive synergetic effect of exercises and physical activity with locomotor training, and other physical modalities (low-level laser therapy, ultrasounds, pulsed electromagnetic fields, electroacupuncture and others). In addition, the use of cell-based therapies is an innovative treatment tool in this field. These strategies may help avoid situations of permanent monoplegic limbs that could lead to amputation.

3.
Cells ; 12(5)2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36899923

RESUMO

Nanomaterials offer a broad spectrum of applications in biomedicine. The shapes of gold nanoparticles could modulate tumor cell behavior. Spherical (AuNPsp), stars (AuNPst) and rods (AuNPr) shapes of polyethylene glycol coated-gold nanoparticles (AuNPs-PEG) were synthesized. Metabolic activity, cellular proliferation, and reactive oxygen species (ROS) were measured and the impact of AuNPs-PEG in metabolic enzymes function was evaluated by RT-qPCR in PC3, DU145, and LNCaP prostate cancer cells. All AuNPs were internalized, and the different morphologies of AuNPs showed to be an essential modulator of metabolic activity. For PC3 and DU145, the metabolic activity of AuNPs was found to rank in the following order from lowest to highest: AuNPsp-PEG, AuNPst-PEG, and AuNPr-PEG. Regarding LNCaP cells, the AuNPst-PEG were less toxic, followed by AuNPsp-PEG and AuNPr-PEG, but it seems not to be dose-dependent. The proliferation was lower in AuNPr-PEG in PC3 and DU145 cells but was stimulated around 10% in most conditions (0.001-0.1 mM) in LNCaP cells (not statistically significant). For 1 mM, LNCaP cells showed a significant decrease in proliferation only for AuNPr-PEG. The outcomes of the current study demonstrated that different AuNPs conformations influence cell behavior, and the correct size and shape must be chosen considering its final application in the field of nanomedicine.


Assuntos
Nanopartículas Metálicas , Nanosferas , Nanotubos , Neoplasias da Próstata , Masculino , Humanos , Ouro
5.
Stem Cell Res Ther ; 10(1): 248, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399129

RESUMO

BACKGROUND: Mesenchymal stem/stromal cells (MSCs) are considered an important candidate in cell therapy and tissue engineering approaches. The culture of stem cells in a 3D environment is known to better resemble the in vivo situation and to promote therapeutically relevant effects in isolated cells. Therefore, the aim of this study was to develop an approach for the direct isolation of MSCs from adipose tissue into a 3D environment, avoiding contact to a 2D plastic surface. Furthermore, the use of a cryoprotective medium for the cryopreservation of whole adipose tissue was evaluated. MATERIALS AND METHODS: Cryopreservation of fresh adipose tissue with and without a cryoprotective medium was compared with regard to the viability and metabolic activity of cells. After thawing, the tissue was embedded in a novel human platelet lysate-based hydrogel for the isolation of MSCs. The migration, yield, viability, and metabolic activity of cells from the 3D matrix were compared to cells from 2D explant culture. Also, the surface marker profile and differentiation capacity of MSCs from the 3D matrix were evaluated and compared to MSCs from isolation by enzymatic treatment or 2D explant culture. RESULTS: The cryopreservation of whole adipose tissue was found to be feasible, and therefore, adipose tissue can be stored and is available for MSC isolation on demand. Also, we demonstrate the isolation of MSCs from adipose tissue into the 3D matrix. The cells derived from this isolation procedure display a similar phenotype and differentiation capacity like MSCs derived by traditional procedures. CONCLUSIONS: The presented approach allows to cryopreserve adipose tissue. Furthermore, for the first time, MSCs were directly isolated from the tissue into a soft 3D hydrogel environment, avoiding any contact to a 2D plastic culture surface.


Assuntos
Tecido Adiposo/metabolismo , Plaquetas/metabolismo , Técnicas de Cultura de Células/métodos , Células-Tronco Mesenquimais/citologia , Adulto , Plaquetas/química , Diferenciação Celular , Movimento Celular , Sobrevivência Celular , Criopreservação , Feminino , Humanos , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Fenótipo
6.
Biosci. j. (Online) ; 33(1): 41-51, jan./feb. 2017. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-965866

RESUMO

The aim of this work was to develop an in vitro conservation protocol for Lippia alba that involved mineral oil and to study the leaf anatomy of L. alba genotypes in in vitro and ex vitro environments. In vitro conservation involved five genotypes; LA-13 and LA-57 (carvone chemotype); LA-22 (linalool chemotype); and LA-29 and LA-44 (citral chemotype). Each genotype was treated with mineral oil, with water, and a control at 18°C and 23°C. Survival (%), shoot height (cm) and leaf color were assessed at 180 and 270 days. The genotypes with the best in vitro conservation outcomes (LA-13 and LA-57) were used to study the anatomy of the leaves. Midrib thickness, leaf blade thickness, adaxial and abaxial cuticles and the number of glandular and tector trichomes were assessed. A temperature of 18°C was optimal for the conservation of genotypes of the carvone chemotypes. The explants were short and had green leaves. This was especially true for LA-57, whose height did not exceed 2.0 cm. At 270 days, the LA-13 and LA-57 genotypes continued to have green and viable leaves, especially LA-57, which had the lowest mean height. Field plants of the carvone chemotype had thicker midribs, leaf blades, and cuticles and had more trichomes. The LA-57 genotype had the most glandular and tector trichomes.


O objetivo deste estudo foi desenvolver um protocolo de conservação in vitro com óleo mineral e estudar a anatomia foliar de genótipos de L. alba nos ambientes in vitro e ex vitro. A conservação in vitro constou de cinco genótipos LA-13 e LA-57 (quimiotipo carvona); LA-22 (quimiotipo linalol); LA-29 e LA-44 (quimiotipo citral), três tratamentos (com óleo mineral, com água e controle) e duas temperaturas 18 e 23°C. Aos 180 e 270 dias, avaliou-se a sobrevivência (%), altura da parte aérea (cm) e coloração das folhas. Os genótipos com os melhores resultados da conservação in vitro (LA-13 e LA-57) foram utilizados para estudos de anatomia. Avaliou-se espessura da nervura central, espessura do limbo foliar, cutículas adaxial e abaxial e quantidade de tricomas glandulares e tectores. A temperatura a 18°C foi a ideal para a conservação dos genótipos do quimiotipo carvona, com folhas verdes e baixos valores para altura, destacando-se LA-57 cuja altura não ultrapassou 2,0 cm. Aos 270 dias LA-13 e LA-57 permaneceram com folhas verdes e viáveis, com destaque para LA-57 com menores médias de altura. A anatomia do quimiotipo carvona mostrou que as plantas de campo apresentaram maiores espessuras da nervura, limbo e cutículas, e maiores quantidades de tricomas. O genótipo LA-57 obteve a maior quantidade de tricomas glandulares e tectores.


Assuntos
Técnicas In Vitro , Óleos Voláteis , Verbenaceae , Lippia/anatomia & histologia
7.
Biosci. j. (Online) ; 29(3): 617-622, may/june 2013.
Artigo em Português | LILACS | ID: biblio-914594

RESUMO

Objetivou-se desenvolver uma metodologia para possibilitar a classificação de plantas de bananeira submetidas à indução de duplicação cromossômica utilizando Redes Neurais Artificiais (RNA). Os dados utilizados neste trabalho foram retirados de uma tese já apresentada, cujo autor estudou a correlação entre a massa fresca de discos foliares e o conteúdo de DNA. A RNA foi implementada com a função de classificação. A taxa de aprendizado e o termo momentum adotados foram respectivamente iguais a 0,01 e 0,2, o número de épocas de treinamento foi 1000. Esses valores foram determinados por meio de tentativa e erro. Para o treinamento, 90% das plantas foram utilizadas e, para validação, 10% do total de 114 autotetraploides produzidos artificialmente por meio de exposição ao antimitódico colchicina. A RNA classificou corretamente 10 das 11 amostras utilizadas para validação. A estatística Kappa foi de 63,33%, o que indica que a RNA pode ainda ser melhorada. A rede neural artificial do tipo Multi Layer Perceptron implementada é eficaz na préseleção de poliploides desejáveis de bananeira Tong Dok Mak.


The objective was to develop a methodology to enable the classification of banana crop subjected to induction of chromosome doubling using Neural Networks (NN). The data used in this study were taken from a thesis already presented, whose authors studied the correlation between fresh weight of leaf discs and DNA content. The NN was implemented by the ranking function. The learning rate and momentum term used were respectively equal to 0.01 and 0.2, the number of training epochs was 1000. These values were determined by trial and error. For training, 90% of the plants were employed, and for validation, 10% of the total of 114 autotetraploids artificially produced by exposure to antimitodic agent colchicine. The NN correctly classified 10 of the 11 samples used for validation. Kappa statistics was 63.33%, which indicates that the NN can be further improved. The artificial neural network-type Multi Layer Perceptron is effectively implemented in the pre-selection of polyploid desirable banana Tong Dok Mak.


Assuntos
Redes Neurais de Computação , Musa , Colchicina , Duplicação Cromossômica
8.
Hemoglobin ; 36(6): 517-25, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23181747

RESUMO

We report a new structural defect of the α2-globin chain presenting with moderate microcytic hypochromic anemia, in six individuals from three unrelated families, living in Portugal and Spain. α-Globin gene deletions were ruled out by gap-polymerase chain reaction (gap-PCR) and multiplex ligation-dependent probe amplification (MLPA). Direct sequencing of the α2-globin gene revealed a substitution of codon 104 [α104(G11)Cys→Arg, TGC>CGC (α2) (HBA2:c.313T>C)]. This new variant, not detectable by high performance liquid chromatography (HPLC) or electrophoresis, was called Hb Iberia, as it was observed for the first time in families from the Iberian Peninsula. Although the mutant allele is transcribed, as indicated by the balanced mRNA α/ß ratio, the abnormal α2 chain could not form a stable tetramer as the cysteine and arginine residues, located at the α1ß1 contact, differ in size, charge and hydrophobicity. Hb Iberia is the third mutation described at codon 104 on the α-globin genes, namely, Hb Sallanches (α2, TGC>TAC) and Hb Oegstgeest (α1, TGC>AGC), also characterized as unstable hemoglobins (Hbs), present on an α-thalassemic phenotype.


Assuntos
Hemoglobinas Anormais/genética , alfa-Globinas/genética , Talassemia alfa/genética , Adulto , Idoso , Substituição de Aminoácidos , Sequência de Bases , Códon , Éxons , Feminino , Genótipo , Hemoglobinas Anormais/química , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Mutação Puntual , Portugal , Conformação Proteica , Espanha , Adulto Jovem , alfa-Globinas/química , Talassemia alfa/diagnóstico
9.
Ciênc. rural ; 40(11): 2268-2273, nov. 2010. tab
Artigo em Português | LILACS | ID: lil-569257

RESUMO

O pinhão-manso (Jatropha curcas L.) vem ganhando importância por seu potencial como insumo ao biodiesel. Estudos visam à adequação agronômica e a cultura de tecidos contribui indiretamente com este aspecto, auxiliando em pesquisas aplicadas como em biotecnologia, em situações que visam à regeneração de plantas. Nesse intuito, é fundamental avaliar, durante os períodos de cultivo dos calos, o comportamento dos metabólitos primários. A massa calogênica, por ocasião da inoculação, não apresentou reserva na forma de carboidratos. Aos 42 dias iniciou a absorção da sacarose do meio, enquanto o acúmulo no explante ocorreu a partir dos 98 dias de cultivo. O teor de aminoácidos foi alto no dia da inoculação e, por volta dos 98 dias, tanto os níveis de aminoácidos quanto os de proteínas decresceram.


The physic nut (Jatropha curcas L.) is gaining importance because of its potential as raw material for biodiesel. Studies aiming the adequacy of agronomic techniques and tissue culture contribute, indirectly, to this aspect, helping applied research as biotechnology, in situations that aim plant regeneration. Therefore, it is essential to evaluate, the behavior of primary metabolites during the callus growing season. The callus mass at the inoculation time showed no carbohydrates reserve. At the 42nd day the sucrose absorption started in the medium, while the accumulation in the explant occurred from the 98th day of cultivation. Amino acid content was high at the inoculation's day and around the 98th day, both amino acids and protein levels decreased.

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