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1.
Med Hypotheses ; 71(2): 286-92, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18434035

RESUMO

Hemangiomas, often categorized as angiogenic diseases, are the most common tumors of infancy, the life span of which is generally divided into proliferating phase, involuting phase, and involuted phase. Despite their high prevalence, the mechanism leading to proliferation hemangiomas formation is poorly understood and the best approach to their management remains controversial. None of the current therapeutic modalities is ideal, partly because the pathogenesis of hemangioma and the mechanism of its proliferation are far from clear. Many clues reveal that estrogen has an important role in developing the vascular system, experimental and clinical evidences accumulated in recent years also suggest the potential for estrogen to influence neovascularization. Based on those, we hypothesize that estrogen play a potential role in the development of hemangiomas, mainly by regulating some key angiogenic factors, including MMP-9, EPCs, VEGF, NO, etc. Accepting the hypothesis to be correct, a therapy that identify estrogen as a potential target for the design of new, more specific treatments can be used to prevent the proliferation hemangiomas formation. The hypothesis may lead a new direction in the study of mechanisms for proliferation hemangiomas formation, and further study of the precise mechanisms for estrogen-induced hemangiomas will produce effective antiestrogens and estrogen receptor antagonists as new medication for the very difficult problem.


Assuntos
Estrogênios/metabolismo , Hemangioma/etiologia , Animais , Sistema Cardiovascular/metabolismo , Proliferação de Células , Feminino , Hemangioma/metabolismo , Humanos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Modelos Biológicos , Modelos Teóricos , Neovascularização Patológica , Neovascularização Fisiológica , Receptores de Estrogênio/metabolismo , Células-Tronco/metabolismo
2.
Chin Med J (Engl) ; 121(15): 1398-406, 2008 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-18959117

RESUMO

BACKGROUND: For cardiovascular tissue engineering, acellularized biomaterials from pig have been widely investigated. Our purpose was to study mechanical properties and biocompatibility of decellularized aorta of fetal pigs (DAFP) to determine its potential as scaffold for small diameter tissue engineered vascular graft. METHODS: Descending aorta of fetal pigs was removed cells using trypsin, ribonuclease and desoxyribonuclease. Mechanical properties of DAFP were evaluated by tensile stress-strain and burst pressure analysis. Assessment of cell adhesion and compatibility was conducted by seeding porcine aortic endothelial cells. To evaluate biocompatibility in vivo, DAFP was implanted subcutaneously into adult male Sprague Dawley rats for 2, 4 and 8 weeks. RESULTS: Histochemistry and scanning electron microscopy examination of DAFP revealed well-preserved extracellular matrix proteins and porous three-dimensional structures. Compared with fresh aorta, DAFP had similar ultimate tensile strength, axial compliance and burst pressure. Cell culture studies in vitro showed that porcine aortic endothelial cells adhered and proliferated on the surfaces of DAFP with excellent cell viability. Subdermal implantation demonstrated that the DAFP did not show almost any immunological reaction and exhibited minimal calcification during the whole follow-up period. CONCLUSION: The DAFP has the potential to serve as scaffolds for small diameter tissue engineered vascular graft.


Assuntos
Aorta/citologia , Prótese Vascular , Engenharia Tecidual/métodos , Animais , Fenômenos Biomecânicos , Antígenos CD4/análise , Cálcio/metabolismo , Células Cultivadas , Matriz Extracelular/fisiologia , Teste de Materiais , Suínos
3.
Asian Pac J Cancer Prev ; 15(2): 855-60, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24568507

RESUMO

BACKGROUND: The purpose of this study was to assess the relationship between different sonographic features of papillary thyroid carcinoma (PTC) on high-frequency ultrasound and cervical lymph node metastasis (CLNM). MATERIALS AND METHODS: We enrolled 548 patients who underwent initial surgery for PTC between May 2011 and December 2012 in our hospital at diagnosis. The sonographic features of 513 PTC nodules in 513 eligible patients, who had single PTC nodules in their thyroid glands, were retrospectively investigated. All patients with a suspect malignant nodule (d<0.5cm) among multiple nodules were initially diagnosed by fine-needle aspiration biopsy (FNAB) to ascertain if the suspect nodule was PTC. The final diagnosis of all the thyroid nodules and existence of CLNM were based on postoperative pathology. Patients were divided into two groups: a positive group with CLNM (224 nodules) and a negative group without CLNM (289 nodules). The following factors were investigated: gender, age, echogenicity, echotexture, size, shape, location, margin, contour, calcification morphology, distance between the nodule and pre- or post-border of the thyroid capsule, vascularity and the differences between the two groups. RESULTS: Correlation analysis showed that shorter distances between the nodule and pre- or post- border of thyroid capsule resulted in greater risk of CLNM (Spearman correlation coefficient=-0.22, p<0.0001). The significant factors in multivariate analysis were age<45yrs, larger size (d>1cm), "wider than tall" shape, extrathyroid extension and mixed flow (internal and peripheral) (p<0.05, OR=0.406, 2.093, 0.461, 1.610, 1.322). CONCLUSIONS: Significant sonographic features of PTC nodules in preoperative high-frequency ultrasound are crucial for predicting CLNM.


Assuntos
Carcinoma Papilar/secundário , Linfonodos/patologia , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Carcinoma Papilar/diagnóstico por imagem , Carcinoma Papilar/cirurgia , Feminino , Seguimentos , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Ultrassonografia , Adulto Jovem
4.
Chin Med J (Engl) ; 124(2): 284-90, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21362382

RESUMO

BACKGROUND: Capsular contracture has become the most common complication associated with breast implant. Transforming growth factor-beta (TGF-ß) is well known for a prominent role in fibrotic diseases. Due to the critical role of TGF-ß in pathogenesis of capsular formation, we utilized thermosensitive C/GP hydrogel to controlled release of TGF-ß receptor kinase inhibitor (SD208) and investigated their effects on capsular contracture. METHODS: In vitro degradation and drug release of C/GP hydrogel were performed. Twenty-four rabbits underwent subpanniculus implantation with 30 ml smooth silicone implants and were randomly divided into four groups as follows: Group 1 received saline solution; Group 2 received SD208; Group 3 received SD208-C/GP; Group 4 received C/GP. At 8 weeks, the samples of capsular tissues were analyzed by hematoxylin and eosin and immunohistological staining. The mRNA expression of collagen III and TGF-ß1 was detected by RT-PCR assay. RESULTS: C/GP hydrogel could be applied as an ideal drug delivery vehicle which supported the controlled release of SD208. SD208-C/GP treatment showed a significant reduction in capsule thickness with fewer vessels. The histological findings confirmed that the lower amounts of inflammatory cells and fibroblasts infiltrate in SD208-C/GP group. In contrast, typical capsules with more vessel predominance were developed in control group. We did not observe the same inhibitory effect of SD208 or C/GP treatment on capsular contracture. Moreover, SD208-C/GP therapy yielded an evident down-regulation of collagen III and TGF-ß1 mRNA expression. CONCLUSIONS: This study demonstrated that controlled release of TGF-ß receptor kinase inhibitor from thermosensitive C/GP hydrogel could significantly prevent capsule formation after mammary implants.


Assuntos
Implante Mamário/efeitos adversos , Quitosana/química , Glicerofosfatos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Animais , Imuno-Histoquímica , Coelhos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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