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1.
Dermatol Ther ; 33(3): e13362, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32239616

RESUMEN

In this study, the application of a recently introduced device based on electromagnetic energy transfer by microwaves for fat reduction, permitted to study specifically the modifications of thick fibrous collagen interlobular septa in the subcutaneous adipose tissue, related to the formation of large clusters of adipocytes. The use of Picrosirius red staining associated with circularly polarized microscopy gave evidence of appreciable modifications of the fibrous connective tissue forming septa. Compact fibrotic bundles of collagen I forming interlobular septa appeared reduced or dissolved, in part substituted by the increase of more diffuse and finely reticular collagen III. Remodeling of fibrous collagen, which formed bridles involved in the appearance at the surface of the skin of dimpling/orange peer pattern typical of cellulite, was observed.


Asunto(s)
Celulitis , Microondas , Colágeno , Humanos , Piel , Grasa Subcutánea
2.
Blood ; 114(2): 459-68, 2009 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-19414862

RESUMEN

Autosomal dominant osteogenesis imperfecta (OI) caused by glycine substitutions in type I collagen is a paradigmatic disorder for stem cell therapy. Bone marrow transplantation in OI children has produced a low engraftment rate, but surprisingly encouraging symptomatic improvements. In utero transplantation (IUT) may hold even more promise. However, systematic studies of both methods have so far been limited to a recessive mouse model. In this study, we evaluated intrauterine transplantation of adult bone marrow into heterozygous BrtlIV mice. Brtl is a knockin mouse with a classical glycine substitution in type I collagen [alpha1(I)-Gly349Cys], dominant trait transmission, and a phenotype resembling moderately severe and lethal OI. Adult bone marrow donor cells from enhanced green fluorescent protein (eGFP) transgenic mice engrafted in hematopoietic and nonhematopoietic tissues differentiated to trabecular and cortical bone cells and synthesized up to 20% of all type I collagen in the host bone. The transplantation eliminated the perinatal lethality of heterozygous BrtlIV mice. At 2 months of age, femora of treated Brtl mice had significant improvement in geometric parameters (P < .05) versus untreated Brtl mice, and their mechanical properties attained wild-type values. Our results suggest that the engrafted cells form bone with higher efficiency than the endogenous cells, supporting IUT as a promising approach for the treatment of genetic bone diseases.


Asunto(s)
Envejecimiento/fisiología , Trasplante de Médula Ósea/métodos , Investigación Fetal , Osteogénesis Imperfecta/prevención & control , Osteogénesis Imperfecta/terapia , Útero/fisiología , Animales , Células de la Médula Ósea/citología , Colágeno/metabolismo , Modelos Animales de Enfermedad , Espacio Extracelular/química , Femenino , Técnicas de Sustitución del Gen , Genes Dominantes , Supervivencia de Injerto , Ratones , Ratones Transgénicos , Osteogénesis Imperfecta/metabolismo , Osteogénesis Imperfecta/patología , Fenotipo , Embarazo , Espectrometría Raman , Tasa de Supervivencia , Donantes de Tejidos
3.
Open Access Maced J Med Sci ; 7(18): 2991-2997, 2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31850107

RESUMEN

BACKGROUND: Recently, it has been developed a new technology for the reduction of subcutaneous adipose tissue through a non-invasive treatment by microwaves. The main objective of the present study is to demonstrate the feasibility of utilising a non-invasive, localised microwaves (MW) device to induce thermal modifications into subcutaneous adipose tissue only by a controlled electromagnetic field that heats up fat preferentially. This device is provided with a special handpiece appropriately cooled, directly contacting the cutaneous surface of the body, which provides a calibrated energy transfer by microwaves. AIM: In this paper, microscopic and ultrastructural modifications of subcutaneous adipose tissue induced by microwaves irradiation are evaluated. METHODS: Our experimental plan was designed for collecting biopsy samples, for each skin region treated with a single irradiation session, 1) before treatment (control), 2) immediately after treatment, 3) after 6 hrs, 4) after 1 month, 5) after 2 months. Bioptic samples from each step were processed for light microscopy and transmission electron microscopy. At the same time, each region where biopsies were collected was subjected to ultrasound examination. Recorded images permitted to evaluate the thickness of different layers as epidermis, dermis, hypodermis, connective fasciae, until to muscle layer, and related modifications induced by treatment. RESULTS: In every biopsy collected at different time-steps, epidermis and superficial dermis appeared not modified compared to control. Differently, already in the short-term biopsies, in the deep dermis and superficial hypodermis, fibrillar connective tissue appeared modified, showing reduction and fragmentation of interlobular collagen septa. The most important adipose tissue modifications were detectable following 1 month from treatment, with a significant reduction of subcutaneous fat, participating both the lysis of many adipocytes and the related phagocytic action of monocytes/macrophages on residuals of compromised structures of adipocytes. In the samples collected two months following treatment, the remnants of adipose tissue appeared normal, and macrophages were completely absent. CONCLUSIONS: Ultrasound, microscopic and ultrastructural evidence are supporting significant effectiveness of the new device treatment in the reduction of subcutaneous fat. In this paper, the possible mechanisms involved in the activation of the monocytes/macrophages system responsible for the removal of adipocytes residuals have also been discussed.

4.
Open Access Maced J Med Sci ; 6(1): 6-14, 2018 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-29483970

RESUMEN

BACKGROUND: Postmenopausal women experience undesired symptoms that adversely affect their quality of life. In the recent years, a specific 12 - week fractional CO2 laser treatment has been introduced, with highly significant relief of symptoms. AIM: The aim of this paper is the identification of the early modifications of structural components of atrophic vaginal mucosa induced by laser irradiation, which is responsible for the restorative processes. MATERIAL AND METHODS: We investigated by microscopical, ultrastructural and biochemical methods the modifications of the structural components of postmenopausal atrophic vaginal mucosa tissues after 1 hour following a single fractional laser CO2 application. RESULTS: In one hour, the mucosal epithelium thickens, with the maturation of epithelial cells and desquamation at the epithelial surface. In the connective tissue, new papillae indenting the epithelium with newly formed vessels penetrating them, new thin fibrils of collagen III are also formed in a renewed turnover of components due to the increase of metalloproteinase - 2. Specific features of fibroblasts support stimulation of their activity responsible of the renewal of the extracellular matrix, with an increase of mechanical support as connective tissue and stimulation of growth and maturation to epithelium thanks to new vessels and related factors delivered. CONCLUSION: We found the activation of regenerative mechanisms expressed both in the connective tissue - with the formation of new vessels, new papillae, and new collagen - and in the epithelium with the associated thickening and desquamation of cells at the mucosal surface.

5.
Tissue Eng ; 12(7): 1985-99, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16889527

RESUMEN

There is increasing interest in designing new biomaterials that could potentially be used in the form of scaffolds as bone substitutes. In this study we used a hydrophobic crosslinked polyurethane in a typical tissue-engineering approach, that is, the seeding and in vitro culturing of cells using a porous scaffold. Using an electromagnetic bioreactor (magnetic field intensity, 2 mT; frequency, 75 Hz), we investigated the effect of the electromagnetic stimulation on SAOS-2 human osteoblast proliferation and calcified matrix production. Cell proliferation was twice as high; expression of decorin, osteocalcin, osteopontin, type I collagen, and type III collagen was greater (1.3, 12.2, 12.1, 10.0, and 10.5 times as great, respectively); and calcium deposition was 5 times as great as under static conditions without electromagnetic stimulation. RT-PCR analysis revealed the electromagnetically upregulated transcription specific for decorin, fibronectin, osteocalcin, osteopontin, transforming growth factor-beta, type I collagen, and type III collagen. The immunolocalization of the extracellular matrix constituents showed their colocalization in the cell-rich areas. The bioreactor and the polyurethane foam were designed to obtain cell colonization and calcified matrix deposition. This cultured biomaterial could be used, in clinical applications, as an osteoinductive implant for bone repair.


Asunto(s)
Calcificación Fisiológica/efectos de la radiación , Proteínas de la Matriz Extracelular/biosíntesis , Poliuretanos , Ingeniería de Tejidos , Reactores Biológicos , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Campos Electromagnéticos , Humanos , Porosidad , Factor de Crecimiento Transformador beta/biosíntesis
6.
J Periodontol ; 73(5): 555-63, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12027260

RESUMEN

BACKGROUND: Microscopic and immunocytochemical studies have demonstrated both similarities and differences between the gingival mucosa and the peri-implant mucosa restored around dental implants. METHODS: This study was performed on 10 samples of peri-implant mucosa from 10 patients who had undergone implant treatment 16 to 18 months before. Microscopic, ultrastructural, and immunocytochemical investigations were performed to characterize the epithelial and connective layers of the peri-implant mucosa. RESULTS: All specimens showed the morphologic characteristics of well restored tissues. The immunocytochemical reactions used to detect cytokeratins demonstrated that the restored peri-implant mucosa had a non-keratinized epithelium. The apical part of the inner epithelium was a few cell layers thick, like the corresponding junctional epithelium, but it stained positively with the markers for the cytokeratins expressed by the stratified epithelia. Ultrastructurally the keratinocytes adjacent to the implant displayed nuclei containing a rich cytoplasm with filaments and specialized intercellular junctions right up to the more superficial strata. Immunocytochemical reactions and ultrastructural observations demonstrated the presence of non-keratinocyte cells; i.e., Langerhans cells, melanocytes, and Merkel cells. Several cells were found to be proliferating by immunoreaction with mAb anti-PCNA, while immunoreactions with mAbs to detect von Willebrand factor, CD34, and vascular endothelial growth factor marked the well-developed networks of blood and lymphatic vessels in the connective tissue. S-100 and protein gene product 9.5 positive nerve fibers were marked. Immunocytochemical reactions with mAbs anti-vimentin, anti-laminin were also performed. CONCLUSIONS: Our results demonstrated that all the epithelial and connective components of the mucosa are involved in the substantial regrowth of the peri-implant tissue and subsequently in the success of the implant.


Asunto(s)
Implantes Dentales , Encía/citología , Citoesqueleto de Actina/ultraestructura , Adulto , Antígenos CD34/análisis , Núcleo Celular/ultraestructura , Células del Tejido Conectivo/citología , Células del Tejido Conectivo/ultraestructura , Citoplasma/ultraestructura , Factores de Crecimiento Endotelial/análisis , Inserción Epitelial/citología , Inserción Epitelial/ultraestructura , Células Epiteliales/citología , Células Epiteliales/ultraestructura , Encía/ultraestructura , Humanos , Inmunohistoquímica , Uniones Intercelulares/ultraestructura , Queratinocitos/citología , Queratinocitos/ultraestructura , Queratinas/análisis , Laminina/análisis , Células de Langerhans/citología , Linfocinas/análisis , Melanocitos/citología , Células de Merkel/citología , Microscopía Electrónica , Persona de Mediana Edad , Fibras Nerviosas/ultraestructura , Proteínas del Tejido Nervioso/análisis , Isoformas de Proteínas/análisis , Proteínas S100/análisis , Tioléster Hidrolasas/análisis , Ubiquitina Tiolesterasa , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular , Vimentina/análisis , Factor de von Willebrand/análisis
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