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1.
AJNR Am J Neuroradiol ; 41(6): 1037-1042, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32467183

RESUMO

BACKGROUND AND PURPOSE: The Neuroform Atlas is a new microstent to assist coil embolization of intracranial aneurysms that recently gained FDA approval. We present a postmarket multicenter analysis of the Neuroform Atlas stent. MATERIALS AND METHODS: On the basis of retrospective chart review from 11 academic centers, we analyzed patients treated with the Neuroform Atlas after FDA exemption from January 2018 to June 2019. Clinical and radiologic parameters included patient demographics, aneurysm characteristics, stent parameters, complications, and outcomes at discharge and last follow-up. RESULTS: Overall, 128 aneurysms in 128 patients (median age, 62 years) were treated with 138 stents. Risk factors included smoking (59.4%), multiple aneurysms (27.3%), and family history of aneurysms (16.4%). Most patients were treated electively (93.7%), and 8 (6.3%) underwent treatment within 2 weeks of subarachnoid hemorrhage. Previous aneurysm treatment failure was present in 21% of cases. Wide-neck aneurysms (80.5%), small aneurysm size (<7 mm, 76.6%), and bifurcation aneurysm location (basilar apex, 28.9%; anterior communicating artery, 27.3%; and middle cerebral artery bifurcation, 12.5%) were common. A single stent was used in 92.2% of cases, and a single catheter for both stent placement and coiling was used in 59.4% of cases. Technical complications during stent deployment occurred in 4.7% of cases; symptomatic thromboembolic stroke, in 2.3%; and symptomatic hemorrhage, in 0.8%. Favorable Raymond grades (Raymond-Roy occlusion classification) I and II were achieved in 82.9% at discharge and 89.5% at last follow-up. mRS ≤2 was determined in 96.9% of patients at last follow-up. The immediate Raymond-Roy occlusion classification grade correlated with aneurysm location (P < .0001) and rupture status during treatment (P = .03). CONCLUSIONS: This multicenter analysis provides a real-world safety and efficacy profile for the treatment of intracranial aneurysms with the Neuroform Atlas stent.


Assuntos
Prótese Vascular , Embolização Terapêutica/instrumentação , Aneurisma Intracraniano/terapia , Vigilância de Produtos Comercializados , Stents , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
2.
Radiography (Lond) ; 24(4): 366-369, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30292507

RESUMO

INTRODUCTION: To analyse the objective structured examination (OSE) results of the first cohorts of radiographers (n = 13) who successfully completed an accredited postgraduate programme in clinical reporting of neurological magnetic resonance imaging (MRI) examinations of the head and cervical spine. METHODS: Forty MRI examinations were used in the OSE which included a range of abnormal cases (prevalence of abnormal examinations approximated 50%) and included: haemorrhage, infarction, demyelination disease, abscess, mass lesions (metastatic deposits, meningioma, glioma, astrocytoma); and disc disease, cord compression, stenosis, ligament rupture, syringomyelia appearances on patients referred from a range of referral sources. Normal variants and incidental findings were also included. True/false positive and negative fractions were used to mark the responses which were also scored for agreement with the previously agreed expected answers based on agreement between three consultant radiologists' reports. RESULTS: The mean sensitivity, specificity and agreement rates for all head and cervical spine investigations (n = 520) combined were 98.86%, 98.08% and 88.37%, respectively. The highest scoring cases were cases which included astrocytoma, disc protrusion with cord compression and glioma. The most common errors were related to syringomyelia, ligament rupture and vertebral fracture. CONCLUSIONS: These OSE results suggest that in an academic setting, and following an accredited postgraduate education programme, this group of radiographers has the ability to correctly identify normal MRI examinations of the head/cervical spine and are able to provide a report on the abnormal appearances to a high standard. Further work is required to confirm the clinical application of these findings.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Cabeça/diagnóstico por imagem , Imageamento por Ressonância Magnética , Neuroimagem , Radiologistas , Acreditação , Encefalopatias/diagnóstico por imagem , Competência Clínica , Educação Médica Continuada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiologistas/educação , Radiologistas/normas , Radiologistas/estatística & dados numéricos , Sensibilidade e Especificidade , Doenças da Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem
3.
Clin Radiol ; 73(5): 507.e1-507.e8, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29246588

RESUMO

AIM: To investigate the feasibility of radiographer-led immediate reporting of chest radiographs (CXRs) referred from general practice. MATERIALS AND METHODS: This 4-month feasibility study (November 2016 to March 2017) was carried out in a single radiology department at an acute general hospital. Comparison was made between CXRs that received an immediate and routine report to determine the number of lung cancers diagnosed, time to diagnosis of lung cancer, time to computed tomography (CT), and number of urgent referrals to respiratory medicine. RESULTS: Forty of 186 sessions (22%) were covered by radiographer immediate reporting. Of the 1,687 CXRs referred from general practice, 558 (33.1%) received an immediate report (radiographer or radiologist). Twenty-two (of 36) CT examinations performed were following an abnormal CXR with an immediate report (mean 0.8 scans/week). Time from CXR to CT was shorter in the immediate report group (n=22 mean 0.9 days SD=2.3) compared to routine reporting (n=14; mean 6.5 SD=3.2; F=27.883, p<0.0001). Time to multidisciplinary team (MDT) discussion was shorter in the immediate reporting group (mean 4.1 SD=2.9) compared to routine reporting (mean 10.6; SD=4.5; F=11.59, p<0.0001). No apparent difference was found for time to discussion at treatment MDT. CONCLUSION: It is feasible to introduce a radiographer-led immediate CXR reporting service. Patients can be taken off the lung cancer pathway sooner with the introduction of radiographer immediate reporting of CXRs and this may improve outcomes for patients. A definitive study assessing outcomes is required to determine whether this will have an impact mortality and morbidity for patients.


Assuntos
Documentação/normas , Medicina Geral , Neoplasias Pulmonares/diagnóstico por imagem , Radiografia Torácica , Encaminhamento e Consulta , Detecção Precoce de Câncer , Estudos de Viabilidade , Feminino , Humanos , Londres , Masculino , Fatores de Tempo
4.
Endocr Relat Cancer ; 21(6): 845-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25217233

RESUMO

This prospective study investigates the relationship between Hashimoto's thyroiditis (HT) and thyroid cancer (TC) in patients with thyroid nodules (TNs). We prospectively examined 2100 patients with 2753 TNs between January 5, 2010 and August 15, 2013. A total of 2023 patients with 2669 TNs met the inclusion criteria of TN ≥5 mm and age ≥18 years. Each patient had blood drawn before fine-needle aspiration biopsy (FNAB) for the following measurements: TSH, free thyroxine, free tri-iodothyronine, thyroid peroxidase antibody (TPOAb), and antithyroglobulin antibody (TgAb). Diagnosis of TC was based on pathology analysis of thyroidectomy tissue. The associations of TC with the independent variables were determined by univariate and multivariate logistic regression analysis and reported as adjusted odds ratio (OR) with 95% CI. A total of 248 malignant nodules were found in 233 patients. There was an association of TC with both increased serum TgAb concentration and age<45 years. An elevated serum TgAb concentration was found in 10.2% of patients (182 of 1790) with benign nodules as compared with 20.6% of patients (48 of 233) with malignant nodules (P≤0.0001). TgAb (OR=2.24: CI=1.57, 3.19) and TSH ≥1 µIU/ml (OR (95% CI)) OR: 1.49 (1.09, 2.03) were significant predictors of TC in multivariate analysis controlling for age and gender. TC was not associated with serum concentrations of TPOAb. In patients with TN, elevated serum concentration of TgAb and TSH ≥1 µIU/ml are independent predictors for TC. The association between HT and TC is antibody specific.


Assuntos
Doença de Hashimoto/patologia , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Autoanticorpos/sangue , Biópsia por Agulha Fina , Feminino , Seguimentos , Doença de Hashimoto/imunologia , Doença de Hashimoto/metabolismo , Doença de Hashimoto/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Tireoglobulina/metabolismo , Neoplasias da Glândula Tireoide/imunologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/imunologia , Nódulo da Glândula Tireoide/metabolismo , Nódulo da Glândula Tireoide/cirurgia , Tireoidectomia , Tiroxina/metabolismo
5.
Br J Cancer ; 110(2): 489-500, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24169344

RESUMO

BACKGROUND: Human papillomavirus (HPV)-positive oropharyngeal cancer (OPSCC) is associated with improved survival compared with HPV-negative disease. However, a minority of HPV-positive patients have poor prognosis. Currently, there is no generally accepted strategy for identifying these patients. METHODS: We retrospectively analysed 270 consecutively treated OPSCC patients from three centres for effects of clinical, pathological, immunological, and molecular features on disease mortality. We used Cox regression to examine associations between factors and OPSCC death, and developed a prognostic model for 3-year mortality using logistic regression analysis. RESULTS: Patients with HPV-positive tumours showed improved survival (hazard ratio (HR), 0.33 (0.21-0.53)). High levels of tumour-infiltrating lymphocytes (TILs) stratified HPV-positive patients into high-risk and low-risk groups (3-year survival; HPV-positive/TIL(high)=96%, HPV-positive/TIL(low)=59%). Survival of HPV-positive/TIL(low) patients did not differ from HPV-negative patients (HR, 1.01; P=0.98). We developed a prognostic model for HPV-positive tumours using a 'training' cohort from one centre; the combination of TIL levels, heavy smoking, and T-stage were significant (AUROC=0·87). This model was validated on patients from the other centres (detection rate 67%; false-positive rate 5.6%; AUROC=0·82). INTERPRETATION: Our data suggest that an immune response, reflected by TIL levels in the primary tumour, has an important role in the improved survival seen in most HPV-positive patients, and is relevant for the clinical evaluation of HPV-positive OPSCC.


Assuntos
Linfócitos do Interstício Tumoral/patologia , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/patologia , Idoso , Feminino , Humanos , Linfócitos do Interstício Tumoral/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/imunologia , Papillomaviridae , Prognóstico , Estudos Retrospectivos
6.
Clin Exp Immunol ; 166(2): 154-63, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21985361

RESUMO

Advanced chronic lymphocytic leukaemia (CLL) is associated with profound immunodeficiency, including changes in T regulatory cells (T(regs)). We determined the pattern of expression of forkhead box P3 (FoxP3), CD25, CD27 and CD127 and showed that the frequency of CD4+ FoxP3+ T cells was increased in CLL patients (12% versus 8% in controls). This increase was seen only in advanced disease, with selective expansion of FoxP3-expressing cells in the CD4+ CD25(low) population, whereas the number of CD4+ CD25(high) FoxP3+ cells was unchanged. CD4+ CD25(low) cells showed reduced expression of CD127 and increased CD27, and this regulatory phenotype was also seen on all CD4 T cells subsets in CLL patients, irrespective of CD25 or FoxP3 expression. Incubation of CD4+ T cells with primary CLL tumours led to a sixfold increase in the expression of FoxP3 in CD4+ CD25- T cells. Patients undergoing treatment with fludarabine demonstrated a transient increase in the percentage of CD4+ FoxP3+ T cells, but this reduced to normal levels post-treatment. This work demonstrates that patients with CLL exhibit a systemic T cell dysregulation leading to the accumulation of CD4+ FoxP3+ T cells. This appears to be driven by interaction with malignant cells, and increased understanding of the mechanisms that are involved could provide novel avenues for treatment.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Fatores de Transcrição Forkhead/biossíntese , Leucemia Linfocítica Crônica de Células B/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Técnicas de Cocultura , Citometria de Fluxo , Humanos , Imunomodulação , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Subunidade alfa de Receptor de Interleucina-7/biossíntese , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Contagem de Linfócitos , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/biossíntese , Vidarabina/análogos & derivados , Vidarabina/uso terapêutico
7.
Bone Marrow Transplant ; 43(11): 853-61, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19104497

RESUMO

Reactivation of CMV is a common complication following allogeneic haematopoietic SCT and is associated with significant morbidity and mortality. The relative importance of the CD4+ and CD8+ components of the CMV-specific immune response in protection from reactivation is unclear. The CMV-specific CD4+ and CD8+ immune response was measured at serial time points in 32 patients following allogeneic HSCT. Intracellular cytokine staining following CMV lysate stimulation and HLA-peptide tetramers were used to determine CMV-specific CD4+ and CD8+ responses, respectively. A deficient CMV-specific CD4+ T-cell immune response within the first 30-50 days post transplant was associated with high risk of viral reactivation. Patients with combined impairment of the CD4+ and CD8+ immune response within the first 100 days were susceptible to late viral reactivation. The frequency of CMV-specific CD4+ T cells correlated with CMV-specific CD8+ T cells, comprising 10% of the whole T-cell repertoire. Early CMV-specific CD4+ T-cell reconstitution was dominated by effector memory cells with normal levels of IL-2 resuming 6 months following transplantation. In summary, both CD4 and CD8 CMV-specific immune reconstitution is required for protection from recurrent activation. Measurement of the magnitude of the CMV-specific CD4+ immune response is useful in managing viral reactivation following HSCT.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Transplante de Células-Tronco Hematopoéticas , Memória Imunológica/imunologia , Adulto , Idoso , Anticorpos Monoclonais/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Homólogo , Adulto Jovem
8.
Eur J Clin Microbiol Infect Dis ; 24(12): 832-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16331335

RESUMO

In neutropenic patients receiving quinolone prophylaxis, bacteremia with viridans group streptococci resistant to quinolones is a known complication. The frequency of occurrence of quinolone-resistant organisms colonizing the oropharynx during antibacterial prophylaxis with a quinolone is not well defined. In 48 patients undergoing hematopoietic stem cell transplantation, the prevalence of quinolone resistance in viridans group streptococci colonizing the oropharynx before and during antibacterial prophylaxis with gatifloxacin or moxifloxacin (most with concomitant penicillin) was determined. For quinolone-resistant isolates, mutations in the genes gyrA and parC, which confer resistance to quinolones, were analyzed. Seventy-four isolates before and 27 isolates during quinolone use were recovered from patients' oropharynxes. The numbers of susceptible isolates recovered before versus during quinolone use were as follows: 52 (70%) versus three (11%) for ciprofloxacin, 66 (89%) versus eight (30%) for levofloxacin, 66 (89%) versus ten (37%) for gatifloxacin, and 67 (91%) versus 11 (41%) for moxifloxacin (p<0.0001). Mutations in gyrA and/or parC were detected in quinolone-resistant isolates. Quinolone-resistant viridans group streptococci are frequently found in the oropharynx of neutropenic patients after a brief (median, 8 days) exposure to gatifloxacin or moxifloxacin.


Assuntos
Antibioticoprofilaxia , Farmacorresistência Bacteriana , Transplante de Células-Tronco de Sangue Periférico , Quinolonas/uso terapêutico , Infecções Estreptocócicas/microbiologia , Estreptococos Viridans/isolamento & purificação , Adulto , Idoso , DNA Girase/genética , DNA Topoisomerase IV/genética , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Neutropenia , Orofaringe/microbiologia , Quinolonas/farmacologia , Infecções Estreptocócicas/prevenção & controle , Estreptococos Viridans/efeitos dos fármacos , Estreptococos Viridans/genética
9.
Injury ; 36(1): 178-84, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15589938

RESUMO

Hybrid external fixators are useful for the management of complex tibial plateau and plafond fractures, as they provide rigid fixation with relatively minimal soft tissue disruption. We reviewed the outcomes of patients with proximal (plateau) and distal (plafond) tibial fractures who were treated with hybrid frames at the Royal North Shore Hospital from 1998 to 2001. Twenty-four patients were identified from the hospital operating records and chart, X-ray and clinical reviews were performed. Follow-up periods averaged 13 months. Fractures were classified using the Ruedi classification for ankle fractures, and the Schatzker classification for the knee fractures. Clinical outcome was assessed using the Iowa knee score and the AOFAS ankle score. As one of the first Australian audits our outcomes were consistent with international standards.


Assuntos
Fixadores Externos , Fixação de Fratura/métodos , Fraturas da Tíbia/cirurgia , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/fisiopatologia , Desenho de Equipamento , Feminino , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Radiografia , Reoperação , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/fisiopatologia , Resultado do Tratamento
10.
Histopathology ; 45(6): 619-24, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15569053

RESUMO

AIMS: Mediastinal large B-cell lymphoma (MLBCL) is a subtype of diffuse large B-cell lymphoma (DLBCL) in the WHO classification with peculiar features, such as female prevalence, young patient age and bulky presentation. It shows a B-cell phenotype with variable expression of surface immunoglobulin, negative CD21 and CD10 and positive CD30 in a large number of cases. An origin from activated thymic B cells has been suggested in several studies. A subpopulation of large, dendritic cells (asteroid cells) strongly expressing CD23 has been identified amongst thymic B cells and these could represent the normal cellular counterpart for this type of primary mediastinal large cell lymphoma. METHODS AND RESULTS: To explore this possibility, we immunostained 24 cases of primary mediastinal lymphomas and 100 cases of non-mediastinal, nodal and extranodal, DLBCLs for CD23 in routinely processed paraffin-embedded tissues. CONCLUSIONS: Our results show that a vast majority (70%) of mediastinal lymphomas strongly express CD23 whilst the same antigen is expressed in only 15% of non-mediastinal nodal DLBCLs and 9% of non-mediastinal extranodal DLBCLs. These results support the hypothesis that most cases of MLBCL arise from activated dendritic thymic B cells. We also suggest that CD23 should be included in the panel of antibodies currently used to characterize this subtype of DLBCL.


Assuntos
Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/patologia , Neoplasias do Mediastino/patologia , Receptores de IgE/biossíntese , Adolescente , Adulto , Antígenos CD20/análise , Proteínas de Ligação a DNA/análise , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-1/análise , Linfoma de Células B/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Masculino , Neoplasias do Mediastino/metabolismo , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-6 , Fatores de Transcrição/análise
11.
J Endocrinol ; 181(1): 11-23, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15072563

RESUMO

Understanding gene expression profiles during early human pancreas development is limited by comparison to studies in rodents. In this study, from the inception of pancreatic formation, embryonic pancreatic epithelial cells, approximately half of which were proliferative, expressed nuclear PDX1 and cytoplasmic CK19. Later, in the fetal pancreas, insulin was the most abundant hormone detected during the first trimester in largely non-proliferative cells. At sequential stages of early fetal development, as the number of insulin-positive cell clusters increased, the detection of CK19 in these cells diminished. PDX1 remained expressed in fetal beta cells. Vascular structures were present within the loose stroma surrounding pancreatic epithelial cells during embryogenesis. At 10 weeks post-conception (w.p.c.), all clusters containing more than ten insulin-positive cells had developed an intimate relationship with these vessels, compared with the remainder of the developing pancreas. At 12-13 w.p.c., human fetal islets, penetrated by vasculature, contained cells independently immunoreactive for insulin, glucagon, somatostatin and pancreatic polypeptide (PP), coincident with the expression of maturity markers prohormone convertase 1/3 (PC1/3), islet amyloid polypeptide, Chromogranin A and, more weakly, GLUT2. These data support the function of fetal beta cells as true endocrine cells by the end of the first trimester of human pregnancy.


Assuntos
Células Epiteliais/citologia , Proteínas de Homeodomínio , Ilhotas Pancreáticas/embriologia , Animais , Biomarcadores/análise , Diferenciação Celular , Núcleo Celular/química , Células Cultivadas , Citoplasma/química , Desenvolvimento Embrionário e Fetal/fisiologia , Células Epiteliais/química , Idade Gestacional , Glucagon/análise , Humanos , Imuno-Histoquímica/métodos , Insulina/análise , Ilhotas Pancreáticas/química , Ilhotas Pancreáticas/citologia , Queratinas/análise , Camundongos , Transativadores/análise
14.
Mech Dev ; 116(1-2): 223-6, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12128229

RESUMO

Haploinsufficiency of SOX9, which encodes a homeodomain transcription factor, results in Campomelic dysplasia. Classical features of this disorder (e.g. skeletal dysplasia and 46,XY sex reversal) are in concordance with SOX9 expression profiles during human embryonic development. We report the robust expression of SOX9 throughout the pancreas during human embryogenesis, at levels of detection equivalent to the developing skeleton and testis. In the early foetal period, SOX9 expression declines and, in particular, is not apparent within the pancreatic islets. In keeping with this profile, examination of three cases with Campomelic dysplasia revealed abnormal pancreatic morphology. Epithelial cells were less densely packed within the mesenchymal stroma and islets less clearly formed with variable expression of hormone and beta cell markers. Taken together, these data indicate a novel potential role for SOX9 in pancreas development during human embryogenesis and early foetal life.


Assuntos
Doenças do Desenvolvimento Ósseo/embriologia , Doenças do Desenvolvimento Ósseo/genética , Proteínas de Grupo de Alta Mobilidade/genética , Pâncreas/anormalidades , Pâncreas/embriologia , Fatores de Transcrição/genética , Disgenesia Gonadal 46 XY/embriologia , Disgenesia Gonadal 46 XY/genética , Humanos , Hibridização In Situ , Recém-Nascido , Masculino , Pâncreas/metabolismo , Fatores de Transcrição SOX9
15.
Artigo em Inglês | MEDLINE | ID: mdl-11312463

RESUMO

A young woman developed an unusual adenocarcinoma in each submandibular salivary gland at an interval of 30 months. This presentation has not been described previously. The possible etiology for this and treatment options are discussed. The choice of diagnostic imaging (ultrasound versus magnetic resonance imaging) is highlighted. As a result of regular follow-ups using diagnostic ultrasound, a second tumor was observed to reach a dimension of 8 mm in less than 6 months. This is probably the first report documenting the extent of initial growth of this rare tumor.


Assuntos
Adenocarcinoma/patologia , Segunda Neoplasia Primária/patologia , Neoplasias da Glândula Submandibular/patologia , Adenocarcinoma/diagnóstico por imagem , Adulto , Evolução Fatal , Feminino , Humanos , Imageamento por Ressonância Magnética , Metástase Neoplásica , Segunda Neoplasia Primária/diagnóstico por imagem , Neoplasias da Glândula Submandibular/diagnóstico por imagem , Ultrassonografia
16.
J Bacteriol ; 182(4): 1080-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10648535

RESUMO

Conjugal transfer of the Ti plasmids from Agrobacterium tumefaciens is controlled by autoinduction via the transcriptional activator TraR and the acyl-homoserine lactone ligand, Agrobacterium autoinducer (AAI). This control process is itself regulated by opines, which are small carbon compounds produced by the crown gall tumors that are induced by the bacteria. Opines control autoinduction by regulating the expression of traR. Transfer of pTiC58 from donors grown with agrocinopines A and B, the conjugal opines for this Ti plasmid, was detected only after the donors had reached a population level of 10(7) cells per cm(2). Donors incubated with the opines and AAI transferred their Ti plasmids at population levels about 10-fold lower than those incubated with opines only. Transcription of the tra regulon, as assessed by monitoring a traA::lacZ reporter, showed a similar dependence on the density of the donor population. However, even in cultures at low population densities that were induced with opines and AAI, there was a temporal lag of between 15 and 20 h in the development of conjugal competence. Moreover, even after this latent period, maximal transfer frequencies required several hours to develop. This lag period was independent of the population density of the donors but could be reduced somewhat by addition of exogenous AAI. Quorum-dependent development of conjugal competence required control by the opine regulon; donors harboring a mutant of pTiC58 deleted for the master opine responsive repressor accR transferred the Ti plasmid at maximum frequencies at very low population densities. Similarly, an otherwise wild-type derivative of pTiC58 lacking traM, which codes for an antiactivator that inhibits TraR activity, transferred at high frequency in a population-independent manner in the absence of the conjugal opines. Thus, while quorum sensing is dependent upon autoinduction, the two phenomena are not synonymous. We conclude that conjugal transfer of pTiC58 is regulated in a quorum-dependent fashion but that supercontrol of the TraR-AAI system by opines and by TraM results in a complex control process that requires not only the accumulation of AAI but also the expression of TraR and the synthesis of this protein at levels that overcome the inhibitory activity of TraM.


Assuntos
Agrobacterium tumefaciens/genética , Conjugação Genética , Regulação Bacteriana da Expressão Gênica , Plasmídeos/genética , Regulon , Agrobacterium tumefaciens/crescimento & desenvolvimento , Agrobacterium tumefaciens/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Meios de Cultura , Humanos , Fosfatos Açúcares/metabolismo
17.
Mol Microbiol ; 27(2): 277-88, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9484884

RESUMO

Conjugal transfer of Agrobacterium tumefaciens Ti plasmids is regulated by two hierarchical signalling systems. Transfer is dependent on a subset of opines produced by the plant tumours induced by the bacterium. Induction also requires an acyl-homoserine lactone signal, called AAI, that is produced by the bacteria themselves. AAI is the co-inducer for TraR, the transcriptional activator required for expression of the tra regulon. Octopine induces conjugation of the octopine-mannityl opine-type Ti plasmids by regulating the expression of traR via OccR, the octopine-dependent activator of the opine regulon. We have discovered a second traR-like gene, trlR, on the octopine-mannityl opine-type Ti plasmids pTi15955 and pTiR10. This gene is located in an operon coding for a mannopine transport system and is expressed as part of the mannityl opine regulon. Sequence analysis indicated that trlR is a frameshift allele of traR, and the resulting protein lacks the carboxy-terminal domain thought to constitute the DNA-binding region of TraR. Expression of trlR inhibited octopine-induced conjugation of pTi15955 and pTiR10 by suppressing the TraR-mediated transcription of the tra and trb operons. Although TrlR had no effect on the expression of traR, TraR activated the expression of trlR. Southern hybridizations indicated that several other Ti and opine-catabolic plasmids contain more than one copy of genes homologous to traR. We propose that trlR is a dominant negative allele of traR and that TrlR inhibits conjugation by forming inactive heteromultimers with TraR.


Assuntos
Agrobacterium tumefaciens/genética , Alelos , Proteínas de Bactérias/genética , Conjugação Genética , DNA Bacteriano , Técnicas de Transferência de Genes , Manitol/análogos & derivados , Plasmídeos , Fatores de Transcrição/genética , Sequência de Aminoácidos , Regulação Bacteriana da Expressão Gênica , Genes Dominantes , Manitol/farmacologia , Dados de Sequência Molecular , Mutagênese
18.
Heart ; 78(2): 131-5, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9326985

RESUMO

OBJECTIVE: To examine the association between serum Lp(a) lipoprotein concentration and clinical and angiographic outcomes five years after coronary artery bypass graft (CABG) surgery. SETTING: A regional cardiothoracic centre, Freeman Hospital, and the University Clinical Investigation Unit, Royal Victoria Infirmary, Newcastle upon Tyne. PATIENTS AND DESIGN: 353 consecutive patients (56 female, 297 male, mean age 57-2 years) undergoing first time CABG surgery for stable angina were studied prospectively. MAIN OUTCOME MEASURES: Late cardiac death (beyond 30 days) and non-fatal myocardial infarction; prevalence of angina five years after surgery in 291 (94%) survivors and vein graft patency (evaluated by patient) in 118 survivors five years after surgery. Serum Lp(a) concentration and lipid profiles were measured before operation, and 3, 6, 12, and 60 months after surgery. Lipid profiles were also measured 24 months after surgery. RESULTS: Weighted Lp(a) concentration (by tertile) was not associated with late cardiac death or with the combination of late cardiac death and non-fatal myocardial infarction, with the presence of angina, or with vein graft occlusion. The association remained non-significant if analysis was restricted to the upper tertile of LDL cholesterol (> 4.1 mmol/l) or to patients under the age of 55 years at the time of surgery. CONCLUSIONS: Serum Lp(a) concentration did not predict late cardiac death, the combination of late cardiac death and non-fatal myocardial infarction, or the prevalence of angina or vein graft occlusion five years after CABG surgery.


Assuntos
Angiografia Coronária , Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Lipoproteína(a)/sangue , Angina Pectoris/complicações , Biomarcadores/sangue , Doença das Coronárias/sangue , Doença das Coronárias/mortalidade , Feminino , Seguimentos , Oclusão de Enxerto Vascular , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Estudos Prospectivos , Resultado do Tratamento
19.
Mol Biochem Parasitol ; 84(2): 155-65, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9084036

RESUMO

Parasite antigens that are strong T cell immunogens represent potential candidates for vaccines against pathogens susceptible to T cell-mediated immunity. We have previously shown that chromatographic fractions of schistosomula extracts contain components that are major T cell immunogen(s) in natural schistosome infections in humans and might contribute to the induction of human protective immunity against this parasite. In the present study, we report on the molecular cloning and on the biochemical characterization of the active components of these fractions. The screening of a schistosomula cDNA expression library with antibodies raised against the fractions allowed the cloning of a cDNA that hybridized to a 0.56-kb mRNA of schistosomula and adult worms. This cDNA contains an open reading frame of 267 base pairs (bp) which encodes a 10-kDa polypeptide. The analysis of the cDNA sequence revealed 70% homology with the sequences of previously reported proteins of unknown function. The native molecules in the active fractions were analyzed by mass spectrometry after additional purification by reverse phase high-performance liquid chromatography (HPLC). This procedure revealed two components in the fractions of molecular mass 10383 +/- 2 Da and 10401 +/- 9 Da. Both polypeptides stimulated immune T cells and yielded tryptic peptides whose sequences matched the sequence of the cloned molecule. These two polypeptides probably correspond to different post-translationally modified forms of the polypeptide encoded by the cloned cDNA.


Assuntos
Antígenos de Helmintos/genética , Schistosoma mansoni/genética , Schistosoma mansoni/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos , Antígenos de Helmintos/isolamento & purificação , Sequência de Bases , Células Clonais , Clonagem Molecular , DNA Complementar/genética , DNA de Helmintos/genética , Humanos , Ativação Linfocitária , Camundongos , Dados de Sequência Molecular , RNA de Helmintos/genética , RNA Mensageiro/genética , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/prevenção & controle , Homologia de Sequência de Aminoácidos , Vacinas/isolamento & purificação
20.
Nature ; 362(6419): 448-50, 1993 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8464476

RESUMO

Conjugal transfer of Ti plasmids from Agrobacterium donors to bacterial recipients is controlled by two types of diffusible signal molecules. Induction is mediated by novel compounds, called opines, that are secreted by crown gall tumours. These neoplasias result from infection of susceptible plants by virulent agrobacteria. The second diffusible signal, called conjugation factor, is synthesized by the donor bacteria themselves. Production of this factor is induced by the opine. Here we show that conjugation is regulated directly by a transcriptional activator, TraR, which requires conjugation factor as a coinducer to activate tra gene expression. TraR is a homologue of LuxR, the lux gene activator from Vibrio fischeri which also requires an endogenously synthesized diffusible coinducer. The two regulatory systems are related; the two activator proteins show amino-acid sequence similarities and the lux system cofactor, autoinducer, will substitute for conjugation factor in the TraR-dependent activation of Ti plasmid tra genes.


Assuntos
Agrobacterium tumefaciens/genética , Proteínas de Bactérias/metabolismo , Conjugação Genética , Homosserina/análogos & derivados , Plasmídeos , Proteínas Repressoras , Transativadores , Fatores de Transcrição/genética , Sequência de Aminoácidos , Proteínas de Bactérias/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Genes Bacterianos , Homosserina/genética , Dados de Sequência Molecular , Fases de Leitura Aberta , Proteínas Recombinantes de Fusão/metabolismo , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
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