Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Sensors (Basel) ; 19(15)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366169

RESUMO

Diabetes is a very complex condition affecting millions of people around the world. Its occurrence, always accompanied by sustained hyperglycemia, leads to many medical complications that can be greatly mitigated when the disease is treated in its earliest stage. In this paper, a novel sensing approach for the early non-invasive detection and monitoring of sustained hyperglycemia is presented. The sensing principle is based on millimeter-wave transmission spectroscopy through the skin and subsequent statistical analysis of the amplitude data. A classifier based on functional principal components for sustained hyperglycemia prediction was validated on a sample of twelve mice, correctly classifying the condition in diabetic mice. Using the same classifier, sixteen mice with drug-induced diabetes were studied for two weeks. The proposed sensing approach was capable of assessing the glycemic states at different stages of induced diabetes, providing a clear transition from normoglycemia to hyperglycemia typically associated with diabetes. This is believed to be the first presentation of such evolution studies using non-invasive sensing. The results obtained indicate that gradual glycemic changes associated with diabetes can be accurately detected by non-invasively sensing the metabolism using a millimeter-wave spectral sensor, with an observed temporal resolution of around four days. This unprecedented detection speed and its non-invasive character could open new opportunities for the continuous control and monitoring of diabetics and the evaluation of response to treatments (including new therapies), enabling a much more appropriate control of the condition.


Assuntos
Glicemia/isolamento & purificação , Diabetes Mellitus Experimental/diagnóstico , Hiperglicemia/diagnóstico , Análise Espectral/métodos , Animais , Diabetes Mellitus Experimental/metabolismo , Humanos , Hiperglicemia/metabolismo , Camundongos
2.
Regen Med ; 15(9): 2053-2065, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33245008

RESUMO

Venous leg ulcers (VLU) represent an uphill economic, health and social burden, aggravated in the elderly. Best-practice care interventions are often insufficient and alternative therapies need to be explored. Herein, we have treated for the first time a chronic VLU in an elderly patient by combining cell therapy and tissue engineering in the context of a compassionate use. The administration of allogeneic adipose-derived mesenchymal stromal cells (MSCs) embedded in a plasma-based bioengineered dermis covering the ulcer bed and also injected into the ulcer margins led to the complete closure of a 10-year recalcitrant VLU in an 85-year-old patient. Regenerative properties of MSCs might be boosted by the use of bioengineered matrices for their delivery.


Assuntos
Úlcera da Perna , Células-Tronco Mesenquimais , Úlcera Varicosa , Tecido Adiposo , Idoso , Idoso de 80 Anos ou mais , Humanos , Úlcera da Perna/terapia , Engenharia Tecidual
3.
Oncotarget ; 8(44): 77385-77399, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-29100394

RESUMO

PDT is widely applied for the treatment of non-melanoma skin cancer pre-malignant and malignant lesions (actinic keratosis, basal cell carcinoma and in situ squamous cell carcinoma). In photodynamic therapy (PDT) the interaction of a photosensitizer (PS), light and oxygen leads to the formation of reactive oxygen species (ROS) and thus the selective tumor cells eradication. Xeroderma pigmentosum (XP) and Gorlin-Goltz Syndrome (GS) patients are at high risk of developing skin cancer in sun-exposed areas. Therefore, the use of PDT as a preventive treatment may constitute a very promising therapeutic modality for these syndromes. Given the demonstrated role of cancer associated fibroblasts (CAFs) in tumor progression and the putative CAFs features of some cancer-prone genodermatoses fibroblasts, in this study, we have further characterized the phenotype of XP and GS dermal fibroblasts and evaluated their response to methyl-δ-aminolevulinic acid (MAL)-PDT compared to that of dermal fibroblasts obtained from healthy donors. We show here that XP/GS fibroblasts display clear features of CAFs and present a significantly higher response to PDT, even after being stimulated with UV light, underscoring the value of this therapeutic approach for these rare skin conditions and likely to other forms of skin cancer were CAFs play a major role.

4.
J Invest Dermatol ; 128(1): 223-36, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17805349

RESUMO

The human antimicrobial peptide LL-37 plays an important role in host defense against infection. In addition to its antimicrobial action, other activities have been described in eukaryotic cells that may contribute to the healing response. In this study, we demonstrated that in vitro human cathelicidin activates migration of the human keratinocyte cell line HaCaT, involving phenotypic changes related to actin dynamics and associated to augmented tyrosine phosphorylation of proteins involved in focal adhesion complexes, such as focal adhesion kinase and paxillin. Other events involved in the LL-37 response were the induction of the Snail and Slug transcription factors, activation of matrix metalloproteinases and activation of the mitogen-activated protein kinase , and phosphoinositide 3-kinase/Akt signaling pathways. These signaling events could be mediated not only through the transactivation of EGFR but also through the induction of G-protein-coupled receptor FPRL-1 expression in these cells. Finally, by in vivo adenoviral transfer of the antimicrobial peptide to excisional wounds in ob/ob mice, we demonstrated that LL-37 significantly improved re-epithelialization and granulation tissue formation. The protective and regenerative activities of LL-37 support its therapeutic potential to promote wound healing.


Assuntos
Peptídeos Catiônicos Antimicrobianos/fisiologia , Cicatrização , Animais , Catelicidinas , Linhagem Celular , Movimento Celular , Diabetes Mellitus Experimental/fisiopatologia , Epitélio/fisiologia , Receptores ErbB/fisiologia , Feminino , Adesões Focais , Tecido de Granulação/fisiologia , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/fisiologia , Fosforilação , Receptores de Formil Peptídeo/genética , Receptores de Formil Peptídeo/fisiologia , Receptores de Lipoxinas/genética , Receptores de Lipoxinas/fisiologia , Regeneração , Transdução de Sinais , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Ativador de Plasminogênio Tipo Uroquinase/fisiologia
5.
Mol Ther ; 15(12): 2186-93, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17712330

RESUMO

Stable and safe corrective gene transfer in stem keratinocytes is necessary for ensuring success in cutaneous gene therapy. There have been numerous encouraging preclinical approaches to cutaneous gene therapy in the past decade, but it is only recently that a human volunteer suffering from junctional epidermolysis bullosa could be successfully grafted using his own non-selected, genetically corrected epidermal keratinocytes. However, ex vivo correction of cancer-prone genetic disorders necessitates a totally pure population of stably transduced stem keratinocytes for grafting. Antibiotic selection is not compatible with the need for full respect for natural cell fate potential and avoidance of immunogenic response in vivo. In order to surmount these problems, we developed a strategy for selecting genetically modified stem cell keratinocytes. Driving ectopic expression of CD24 (a marker of post-mitotic keratinocytes) at the surface of clonogenic keratinocytes permitted their full selection. Engineered keratinocytes expressing CD24 and the green fluorescent protein (GFP) tracer gene were shown to retain their original growth and differentiation potentials both in vitro and in vivo over 300 generations. Also, they did not exhibit signs of genetic instability. Using ectopic expression of CD24 as a selective marker of genetically modified human epidermal stem cells appears to be the first realistic approach to safe cutaneous gene therapy in cancer-prone disease conditions.


Assuntos
Antígeno CD24/genética , Divisão Celular , Queratinócitos/citologia , Antígeno CD24/imunologia , Separação Celular , Fluorescência , Humanos , Cariotipagem , Queratinócitos/imunologia , Regeneração , Fenômenos Fisiológicos da Pele
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa