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1.
Eur J Breast Health ; 20(1): 31-37, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38187100

RESUMO

Objective: Breast cancer is an important topic worldwide, posing morbidity and mortality to women. Considerable efforts have been put in the early recognition of malignancy through different screening methods, such as mammography and ultrasound. The precise localization of infraclinical malignant lesions is key in surgical management and magnetic seeds gather particular interest for this purpose. As with other systems, a need for reintervention may be needed to obtain adequate surgical margins. This work evaluated the relation between the need for surgical reintervention in order to obtain negative margins and geodimensional and histological parameters. The main objective was the identification of parameters significantly associated with reintervention for margin widening. Materials and Methods: A retrospective analysis of 198 patients from a single centre was performed. The association between pre-defined geodimensional and histological parameters and the need for margin widening in infraclinical lesions marked with magnetic seed was evaluated. Results: Results showed that reintervention to widen margins was significantly higher in patients with ductal carcinoma in situ (DCIS) in the pre-operative biopsy when compared with invasive carcinoma (p = 0.03) in the bivariate analysis. No statistically significant differences were observed between the need for reintervention and lesion size (p = 0.197), breast quadrant location (p = 0.626) and distance of skin to lesion (p = 0.356). Conclusion: This work suggests that a more invasive margin clearance in lesions with a pre-operative DCIS diagnosis might obviate the need for reintervention to obtain negative margins. On the other hand, it is not necessary to be surgically more invasive in larger lesions, deeply located or that are present in a certain quadrant, since there are no significant differences regarding the need for reintervention.

2.
Int J Surg Case Rep ; 66: 342-345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31924577

RESUMO

INTRODUCTION: Intestinal malrotation results from failure of the normal gut rotation during embryological development. It is usually diagnosed in early childhood when it becomes symptomatic. Aetiology of intestinal malrotation has been scarcely addressed although relevant roles have been attributed to a few genes involved in gastrointestinal formation and association with certain syndromes has been suggested. PRESENTATION OF CASE: We describe the case of a 23-year-old woman with 12p deletion syndrome who presented with clinical symptoms of occlusion to the emergency department. Analytically, an elevation of inflammatory parameters was confirmed and imaging revealed pneumoperitoneum originated on cecum perforation. The patient was submitted to surgery with favorable evolution. DISCUSSION: Clinical manifestation of intestinal malrotation is uncommon in the adult population but can have severe consequences if not diagnosed early. The abnormal positioning of the duodenojejunal loop compressed by Ladd's bands, can lead to obstruction and ischemia. Surgery via Ladd's procedure commonly applies and elective treatment may prevent added morbidity. Intestinal malrotation has been associated to certain syndromes but no prior association to chromosome 12p deletion has been described. Occlusion in a patient with 12p chromosome deletion should raise prompt suspicion for intestinal malrotation. Moreover, diagnosis of 12p chromosome deletion should increase attention towards gastrointestinal changes since elective surgery may diminish morbidity. CONCLUSION: Intestinal malrotation results from abnormal embryological rotation of the midgut and is associated with certain syndromes. This paper firstly associates intestinal malrotation to chromosome 12p deletion. The possibility to address it electively may prevent morbidity in patients with this syndrome.

3.
J Orthop Res ; 28(9): 1193-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20187118

RESUMO

In this work, the ability of gellan gum hydrogels coupled with autologous cells to regenerate rabbit full-thickness articular cartilage defects was tested. Five study groups were defined: (a) gellan gum with encapsulated chondrogenic predifferentiated rabbit adipose stem cells (ASC + GF); (b) gellan gum with encapsulated nonchondrogenic predifferentiated rabbit adipose stem cells (ASC); (c) gellan gum with encapsulated rabbit articular chondrocytes (AC) (standard control); (d) gellan gum alone (control); (e) empty defect (control). Full-thickness articular cartilage defects were created and the gellan gum constructs were injected and left for 8 weeks. The macroscopic aspect of the explants showed a progressive increase of similarity with the lateral native cartilage, stable integration at the defect site, more pronouncedly in the cell-loaded constructs. Tissue scoring showed that ASC + GF exhibited the best results regarding tissue quality progression. Alcian blue retrieved similar results with a better outcome for the cell-loaded constructs. Regarding real-time PCR analyses, ASC + GF had the best progression with an upregulation of collagen type II and aggrecan, and a downregulation of collagen type I. Gellan gum hydrogels combined with autologous cells constitute a promising approach for the treatment of articular cartilage defects, and adipose derived cells may constitute a valid alternative to currently used articular chondrocytes.


Assuntos
Doenças das Cartilagens/tratamento farmacológico , Cartilagem Articular/efeitos dos fármacos , Hidrogéis/farmacologia , Polissacarídeos Bacterianos/farmacologia , Transplante de Células-Tronco , Tecido Adiposo/citologia , Agrecanas/genética , Animais , Doenças das Cartilagens/patologia , Cartilagem Articular/patologia , Cartilagem Articular/fisiologia , Divisão Celular/efeitos dos fármacos , Condrócitos/citologia , Condrócitos/fisiologia , Condrogênese/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo II/genética , Terapia Combinada , Feminino , Injeções , Coelhos , Regeneração/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOX9/genética , Células-Tronco/citologia , Engenharia Tecidual/métodos , Transplante Autólogo
4.
Tissue Eng Part A ; 14(10): 1651-61, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18611147

RESUMO

In this work, scaffolds derived from a new biomaterial originated from the combination of a natural material and a synthetic material were tested for assessing their suitability for cartilage tissue engineering applications. In order to obtain a better outcome result in terms of scaffolds' overall properties, different blends of natural and synthetic materials were created. Chitosan and polybutylene succinate (C-PBS) 50/50 (wt%) were melt blended using a twin-screw extruder and processed into 5 x 5 x 5 mm scaffolds by compression moulding with salt leaching. Micro-computed tomography analysis calculated an average of 66.29% porosity and 92.78% interconnectivity degree for the presented scaffolds. The salt particles used ranged in size between 63 and 125 mum, retrieving an average pore size of 251.28 mum. Regarding the mechanical properties, the compressive modulus was of 1.73 +/- 0.4 MPa (E(sec) 1%). Cytotoxicity evaluation revealed that the leachables released by the developed porous structures were not harmful to the cells and hence were noncytotoxic. Direct contact assays were carried out using a mouse bone marrow-derived mesenchymal progenitor cell line (BMC9). Cells were seeded at a density of 5 x 10(5) cells/scaffold and allowed to grow for periods up to 3 weeks under chondrogenic differentiating conditions. Scanning electron microscopy analysis revealed that the cells were able to proliferate and colonize the scaffold structure, and MTS test demonstrated cell viability during the time of the experiment. Finally, Western blot performed for collagen type II, a natural cartilage extracellular matrix component, showed that this protein was being expressed by the end of 3 weeks, which seems to indicate that the BMC9 cells were being differentiated toward the chondrogenic pathway. These results indicate the adequacy of these newly developed C-PBS scaffolds for supporting cell growth and differentiation toward the chondrogenic pathway, suggesting that they should be considered for further studies in the cartilage tissue engineering field.


Assuntos
Cartilagem/citologia , Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Cartilagem/ultraestrutura , Adesão Celular , Sobrevivência Celular , Quitosana/química , Células-Tronco Mesenquimais/ultraestrutura , Camundongos , Microscopia Eletrônica de Varredura , Polienos/química , Succinatos/química
5.
Curr Stem Cell Res Ther ; 1(3): 345-64, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18220879

RESUMO

The progressive increase in life expectancy within the last century has led to the appearance of novel health related problems, some of those within the musculoskeletal field. Among the latter, one can find diseases such as osteoporosis, rheumatoid arthritis and bone cancer, just to mention some of the most relevant. Other related problems are those that arise from serious injuries, often leading to non-recoverable critical size defects. The therapies currently used to treat this type of diseases/injuries are based on the use of pharmaceutical agents, auto/allotransplant and synthetic materials. However, such solutions present a number of inconveniences and therefore, there is a constant search for novel therapeutic solutions. The appearance of a novel field of science called Tissue engineering brought some hope for the solution of the above mentioned problems. In this field, it is believed that by combining a 3D porous template--scaffold--with an adequate cell population, with osteo or chondrogenic potential, it will be possible to develop bone and cartilage tissue equivalents that when implanted in vivo, could lead to the total regeneration of the affected area. This ideal cell population should have a series of properties, namely a high osteo and chondrogenic potential and at the same time, should be easily expandable and maintained in cultures for long periods of time. Due to its natural and intrinsic properties, stem cells are one of the best available cell types. However, after this sentence, the readers may ask, "Which Stem Cells?". During the last 10/15 years, the scientific community witnessed and reported the appearance of several sources of stem cells with both osteo and chondrogenic potential. Therefore, the present review intends to make an overview of data reported on different sources of adult stem cells (bone marrow, periosteum, adipose tissue, skeletal muscle and umbilical cord) for bone and cartilage regenerative medicine, namely those focusing on the differentiation potential of the latter as well as in vivo proof of concept of their applicability. Simultaneously novel aspects of adult stem cells biotechnology such as their immunogenic characteristics and cell expansion methodologies will also be put forward. The present review also points out on issues such as the bone and cartilage regenerative market, and gives a brief description on bone and cartilage bone biology, so the readers can have a true idea of the current state of the art, and how adult stem cells can be an added value to this field.


Assuntos
Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Cartilagem/citologia , Cartilagem/fisiologia , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Células-Tronco/fisiologia , Engenharia Tecidual/métodos , Adulto , Doenças Ósseas/terapia , Doenças das Cartilagens/terapia , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/fisiologia , Transplante Autólogo , Transplante Homólogo , Veias Umbilicais/citologia , Veias Umbilicais/fisiologia
6.
Clin Cancer Res ; 11(16): 5869-77, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16115928

RESUMO

PURPOSE: P-cadherin overexpression has been reported in breast carcinomas, where it was associated with proliferative high-grade histological tumors. This study aimed to analyze P-cadherin expression in invasive breast cancer and to correlate it with tumor markers, pathologic features, and patient survival. Another purpose was to evaluate the P-cadherin promoter methylation pattern as the molecular mechanism underlying this gene regulation. EXPERIMENTAL DESIGN: Using a series of invasive breast carcinomas, P-cadherin expression was evaluated and correlated with histologic grade, estrogen receptor, MIB-1, and p53 and c-erbB-2 expression. In order to assess whether P-cadherin expression was associated with changes in CDH3 promoter methylation, we studied the methylation status of a gene 5'-flanking region in these same carcinomas. This analysis was also done for normal tissue and for a breast cancer cell line treated with a demethylating agent. RESULTS: P-cadherin expression showed a strong correlation with high histologic grade, increased proliferation, c-erbB-2 and p53 expression, lack of estrogen receptor, and poor patient survival. This overexpression can be regulated by gene promoter methylation because the 5-Aza-2'-deoxycytidine treatment of MCF-7/AZ cells increased P-cadherin mRNA and protein levels. Additionally, we found that 71% of P-cadherin-negative cases showed promoter methylation, whereas 65% of positive ones were unmethylated (P = 0.005). The normal P-cadherin-negative breast epithelial cells showed consistent CDH3 promoter methylation. CONCLUSIONS: P-cadherin expression was strongly associated with tumor aggressiveness, being a good indicator of clinical outcome. Moreover, the aberrant expression of P-cadherin in breast cancer might be regulated by gene promoter hypomethylation.


Assuntos
Neoplasias da Mama/patologia , Caderinas/biossíntese , Metilação de DNA , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Caderinas/genética , Linhagem Celular Tumoral , Decitabina , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Antígeno Ki-67/análise , Pessoa de Meia-Idade , Invasividade Neoplásica , Valor Preditivo dos Testes , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida , Proteína Supressora de Tumor p53/análise
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