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1.
Nature ; 627(8003): 281-285, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286342

RESUMO

Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH)1-3. These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase4-6. A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3)7. Here we report a dynamical measurement of the mass of the black hole in a luminous quasar at a redshift of 2, with a look back in time of 11 billion years, by spatially resolving the broad-line region (BLR). We detect a 40-µas (0.31-pc) spatial offset between the red and blue photocentres of the Hα line that traces the velocity gradient of a rotating BLR. The flux and differential phase spectra are well reproduced by a thick, moderately inclined disk of gas clouds within the sphere of influence of a central black hole with a mass of 3.2 × 108 solar masses. Molecular gas data reveal a dynamical mass for the host galaxy of 6 × 1011 solar masses, which indicates an undermassive black hole accreting at a super-Eddington rate. This suggests a host galaxy that grew faster than the SMBH, indicating a delay between galaxy and black hole formation for some systems.

2.
Br J Radiol ; 80(952): 267-73, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17068011

RESUMO

Breast cancer is a major source of morbidity and mortality in the elderly population and the number of patients will increase by 30% in future decades. Surgery and endocrine therapy could be considered as the standard treatment in elderly breast cancer patients, but anaesthesia for surgery requires a specific approach taking into account physiological and psychological alterations secondary to ageing. In cases with major alterations of performance status, percutaneous radiofrequency ablation (RFA) could be substituted for the surgical treatment. The aim of the current study is to evaluate the efficacy and feasibility of this technique. Five tumours in four consecutive patients (aged 79-82 years) contraindicated for surgery with symptomatic cT1-2N0M0, positive oestrogen receptor status, low grade were treated by percutaneous radiofrequency-lump ablation under local analgesia, using percutaneous ultrasound guidance. Thermal lesions were produced with RF power 30 W, at a frequency of 500 kHz. Ultrasound-guided percutaneous biopsy of the RF treated breast was performed during the follow-up. We report a successful RFA lump ablation experience in the treatment of four tumours (4/5). One local recurrence occurred within 4 months after RFA. The other biopsies taken during the follow up showed all fat necrosis within the oil cyst and no malignant cells. One abscess occurred at 9 months within the treated area. After a mean follow up of 29.4 months, all the patients are still alive without any other signs of recurrence or metastases. Ultrasound-guided percutaneous RFA is safe and feasible in the management of breast cancer in elderly patients. Nevertheless, further large comparative studies are needed in order to validate such a minimally invasive procedure in current practice.


Assuntos
Neoplasias da Mama/cirurgia , Ablação por Cateter/métodos , Ultrassonografia de Intervenção/métodos , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia/diagnóstico , Resultado do Tratamento
3.
Breast Cancer Res Treat ; 92(1): 61-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15980992

RESUMO

PURPOSE: The present study is designed to evaluate and compare percutaneous radiologic arm port (R) and surgical subclavian port (S) devices in two homogeneous sets of breast cancer patients in terms of safety, efficacy, quality of life (QoL) and cost analysis. MATERIAL AND METHODS: This study involved a retrospective review of a prospective databank including 200 consecutive port device implantation attempted procedures performed over a 4-year period, in two similar groups of 100 breast cancer women who underwent either the surgical cephalic vein cutdown approach or the percutaneous basilic vein catheterization for intravenous adjuvant chemotherapy. Parameters analyzed included technical success, procedure duration, complications, QoL and cost evaluation for both techniques. RESULTS: The success rate for port implantation was higher for R than for S placement (96% versus 91%). Mean implant duration time was 5.6 and 7.6 months for R and S, respectively. The overall complication rate was 10 and 16% for R and S, respectively. Mean implant duration time, without any complication or death, was 6.4 and 7.8 months for R and S, respectively. Six and seven percent for R and S, respectively, had to be removed prematurely. Both techniques exhibited very good QoL. Direct costs were respectively euro 230.8 and 219.1 for R and S, respectively. CONCLUSION: The significant advantages of R over S include higher success rate, higher cosmetic results despite a 15% relative overcost for R placement. Both are indicated for breast cancer chemotherapy treatment, nevertheless R placement is mandatory in anxious patients who fear surgery, in case of previous cervico-thoracic irradiation or upper extremity venous thrombosis, or in patients at risk of respiratory insufficiency.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Cateterismo Periférico/métodos , Tratamento Farmacológico/instrumentação , Qualidade de Vida , Análise e Desempenho de Tarefas , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Cateterismo Periférico/economia , Cateteres de Demora , Feminino , Custos de Cuidados de Saúde , Humanos , Pessoa de Meia-Idade , Radiografia Intervencionista/métodos , Estudos Retrospectivos , Resultado do Tratamento , Venostomia/métodos
4.
Onkologie ; 27(2): 157-60, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15138348

RESUMO

BACKGROUND: Liver metastases from head and neck cancer are rare (4.4%) and associated with a poor prognosis (median survival 4 months). The objective of the present study was to evaluate the radiological and biological features of liver metastases from head and neck (H and N) squamous cell carcinomas in 24 patients among 550 recurrent H and N cancer patients in our data bank. RESULTS: At first presentation of liver nodules, liver enzyme levels (LEL) were found to be abnormal in 46% of patients (n = 11). Ultrasound features included miscellaneous presentations such as hypoechogenic (n = 21), hyperechogenic hemangioma-like lesions (n = 2), owl's eye (n = 2) or cyst-like liver nodules (n = 3). Hepatomegaly was present in 48% of the cases without any sign of portal hypertension and without any ascites. 1 month before death, all patients presented with abnormal LEL. Liver imaging showed an increase of 1.8x in size and of 2x in number of the tumor nodules. Hepatomegaly was present in 54%. Little ascites appeared in 2 cases, with no evidence of portal hypertension or liver insufficiency. Median disease-free interval and overall survival from recurrence were 10.8 and 4 months, respectively. CONCLUSION: Ultrasound is convenient, cheap, without any side effect, and can provide additional information about liver metastases in H and N cancer patients. In patients with a history of H and N carcinoma ultrasound should be used to screen for isolated hepatic nodules even in the presence of normal liver function and if LDH elevation should be the only biological sign of alert.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/mortalidade , Neoplasias de Células Escamosas/diagnóstico por imagem , Neoplasias de Células Escamosas/secundário , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Intervalo Livre de Doença , Feminino , França/epidemiologia , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Neoplasias de Células Escamosas/diagnóstico , Neoplasias de Células Escamosas/mortalidade , Radiografia , Estudos Retrospectivos , Análise de Sobrevida
5.
JBR-BTR ; 87(1): 17-20, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15055328

RESUMO

Gastrocolic fistula (GCF) has previously been described with percutaneous endoscopic gastrostomy procedures. However the present case of GCF is to our knowledge the first reported in the literature. It developed as a complication of the fluoroscopic technique three months after percutaneous fluoroscopicically guided gastrostomy-tube insertion. GCF was symptomless and was discovered during button replacement in a 74-year-old head and neck cancer patient. In patients with complex upper abdominal anatomy, the use of US or CT should be recommended to avoid such problem.


Assuntos
Doenças do Colo/etiologia , Nutrição Enteral , Fístula Gástrica/etiologia , Gastrostomia , Fístula Intestinal/etiologia , Neoplasias Faríngeas/terapia , Complicações Pós-Operatórias/etiologia , Desnutrição Proteico-Calórica/terapia , Punções , Idoso , Doenças do Colo/diagnóstico por imagem , Doenças do Colo/cirurgia , Fluoroscopia , Fístula Gástrica/diagnóstico por imagem , Fístula Gástrica/cirurgia , Humanos , Fístula Intestinal/diagnóstico por imagem , Fístula Intestinal/cirurgia , Masculino , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/cirurgia , Reoperação , Tomografia Computadorizada por Raios X
6.
Interv Neuroradiol ; 8(3): 317-20, 2002 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-20594491

RESUMO

SUMMARY: We report an unusual case (never described) of a false aneurysm of the maxillary artery following irradiation and biopsy that ruptured into the nasopharynx in an 34-year-old man who presented with severe epistaxis 15 months after radiation therapy of the nasopharynx (80 Gy). Angiography revealed a fusiform aneurysm of the second portion of the maxillary artery, which was successfully embolized but the patient died from a pseudomonas septicemia three months later. False aneurysms of the maxillary artery following irradiation are exceptional complications. Despite a successful endovascular treatment, the absence of collateral revascularization did not allow to complete healing of the radionecrotic pharyngeal area and led to a lethal septicemia.

7.
J Radiol ; 82(11): 1633-6, 2001 Nov.
Artigo em Francês | MEDLINE | ID: mdl-11894549
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