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1.
Br J Dermatol ; 171(5): 1129-37, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24720697

RESUMO

BACKGROUND: Propranolol, a ß-adrenergic receptor (AR) antagonist, is an effective treatment for endangering infantile haemangioma (IH). Dramatic fading of cutaneous colour is often seen a short time after initiating propranolol therapy, with accelerated regression of IH blood vessels discerned after weeks to months. OBJECTIVES: To assess a possible role for haemangioma-derived pericytes (HemPericytes) isolated from proliferating and involuting phase tumours in apparent propranolol-induced vasoconstriction. METHODS: HemPericytes were assayed for contractility on a deformable silicone substrate: propranolol (10 µmol L(-1)) restored basal contractile levels in HemPericytes that were relaxed with the AR agonist epinephrine. Small interfering RNA knockdown of ß2-AR blunted this response. HemPericytes and haemangioma-derived endothelial cells were co-implanted subcutaneously in nude mice to form blood vessels; at day 7 after injection, mice were randomized into vehicle and propranolol-treated groups. RESULTS: HemPericytes expressed high levels of ß2-AR mRNA compared with positive control bladder smooth muscle cells. In addition, ß2-AR mRNA levels were relatively high in IH specimens (n = 15) compared with ß1-AR, ß3-AR and α1b-AR. Normal human retinal and placental pericytes were not affected by epinephrine or propranolol in this assay. Propranolol (10 µmol L(-1)) inhibited the proliferation of HemPericytes in vitro, as well as normal pericytes, indicating a nonselective effect in this assay. Contrast-enhanced microultrasonography of the implants after 7 days of treatment showed significantly decreased vascular volume in propranolol-treated animals, but no reduction in vehicle-treated animals. CONCLUSIONS: These findings suggest that the mechanism of propranolol's effect on proliferating IH involves increased pericytic contractility.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Hemangioma/fisiopatologia , Pericitos/fisiologia , Propranolol/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Volume Sanguíneo , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/metabolismo , Epinefrina/farmacologia , Hemangioma/irrigação sanguínea , Humanos , Masculino , Camundongos Nus , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Distribuição Aleatória , Receptores Adrenérgicos beta 1/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Transplante Heterólogo , Células Tumorais Cultivadas , Vasoconstritores/farmacologia , Vasodilatadores/farmacologia
2.
Acta Radiol ; 49(9): 995-1004, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18651256

RESUMO

BACKGROUND: Accurate staging is necessary to determine the appropriate therapy in patients with lung cancer. Few studies have compared integrated fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) and contrast-enhanced CT in the characterization and staging of pulmonary tumors considered eligible for surgical resection. PURPOSE: To compare 18F-FDG PET/CT with standard contrast-enhanced CT for the diagnosis and staging of lung neoplasms eligible for surgical resection. MATERIAL AND METHODS: Seventy-six consecutive patients (56 male, 20 female; mean age+/-SD, 63.4+/-20 years) with 84 pulmonary tumors suspected for malignancy and considered eligible for surgical resection were prospectively enrolled. Seventy-three malignant (65 non-small-cell lung carcinomas, one small-cell lung cancer, two carcinoids, and five metastases) and 11 benign lung tumors (three hamartomas, two sarcoidosis, one amyloidosis, one Wegener granulomatosis, one tuberculosis, and three areas of scarring) were finally diagnosed by histology. Tumor staging was based on the revised American Joint Committee on Cancer. RESULTS: In lesion characterization, the sensitivity and specificity of 18F-FDG PET/CT versus contrast-enhanced CT were 90% vs. 83% and 18% vs. 63% (P<0.05, McNemar test), respectively. In nodal staging, the sensitivity and specificity of 18F-FDG PET/CT versus contrast-enhanced CT were 78% vs. 46% and 80% vs. 93% (P<0.05), respectively. CONCLUSION: In patients with lung neoplasms considered eligible for surgical resection, (18)F-FDG PET/CT versus contrast-enhanced CT revealed higher sensitivity in nodal staging, but lower specificity both in lesion characterization and nodal staging.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Pulmonares/diagnóstico , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Meios de Contraste , Feminino , Humanos , Aumento da Imagem , Pneumopatias/diagnóstico , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Estudos Prospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
5.
Radiol Med ; 87(6): 758-62, 1994 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-8041928

RESUMO

Stereotaxis is a well-known technique allowing fine-needle aspiration cytology and preoperative localization of the nonpalpable breast lesions seen on mammograms, permitting early diagnosis and easy surgical ablation. The authors report on their experience (126 cases) with stereotactic aspiration (85 cases) and preoperative localization (41 cases) of nonpalpable lesions. The technique allowed to hit the lesion in 115/126 cases (91.3%). Cytology showed 24 cases of cancer and 38 benign lesions (3 of them were false negatives); in 8 cases cytology was suspect (7 cancers and 1 sclerosing adenosis) and in 15 inadequate (17.7%). Sensitivity and specificity were confirmed by histology or follow-up (6 months + 6 months); sensitivity was 91.2% and specificity 97.2% (excluding inadequate cases). The 41 needle localizers were useful to detect 37 malignancies. Fifty-one lesions were biopsied: 37 of them were malignant and 14 benign (benign/malignant ratio = 0.38/1).


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia/métodos , Radiografia Intervencionista/métodos , Adulto , Idoso , Biópsia por Agulha/instrumentação , Biópsia por Agulha/métodos , Biópsia por Agulha/estatística & dados numéricos , Mama/patologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Citodiagnóstico/instrumentação , Citodiagnóstico/métodos , Citodiagnóstico/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Mamografia/instrumentação , Mamografia/estatística & dados numéricos , Pessoa de Meia-Idade , Radiografia Intervencionista/instrumentação , Radiografia Intervencionista/estatística & dados numéricos , Sensibilidade e Especificidade , Técnicas Estereotáxicas/instrumentação , Técnicas Estereotáxicas/estatística & dados numéricos
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