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1.
Eur J Nucl Med Mol Imaging ; 45(13): 2285-2299, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30259091

RESUMO

BACKGROUND: Effective anticancer therapy is thought to involve induction of tumour cell death through apoptosis and/or necrosis. [18F]ICMT-11, an isatin sulfonamide caspase-3/7-specific radiotracer, has been developed for PET imaging and shown to have favourable dosimetry, safety, and biodistribution. We report the translation of [18F]ICMT-11 PET to measure chemotherapy-induced caspase-3/7 activation in breast and lung cancer patients receiving first-line therapy. RESULTS: Breast tumour SUVmax of [18F]ICMT-11 was low at baseline and unchanged following therapy. Measurement of M30/M60 cytokeratin-18 cleavage products showed that therapy was predominantly not apoptosis in nature. While increases in caspase-3 staining on breast histology were seen, post-treatment caspase-3 positivity values were only approximately 1%; this low level of caspase-3 could have limited sensitive detection by [18F]ICMT-11-PET. Fourteen out of 15 breast cancer patients responded to first-line chemotherapy (complete or partial response); one patient had stable disease. Four patients showed increases in regions of high tumour [18F]ICMT-11 intensity on voxel-wise analysis of tumour data (classed as PADS); response was not exclusive to patients with this phenotype. In patients with lung cancer, multi-parametric [18F]ICMT-11 PET and MRI (diffusion-weighted- and dynamic contrast enhanced-MRI) showed that PET changes were concordant with cell death in the absence of significant perfusion changes. CONCLUSION: This study highlights the potential use of [18F]ICMT-11 PET as a promising candidate for non-invasive imaging of caspase3/7 activation, and the difficulties encountered in assessing early-treatment responses. We summarize that tumour response could occur in the absence of predominant chemotherapy-induced caspase-3/7 activation measured non-invasively across entire tumour lesions in patients with breast and lung cancer.


Assuntos
Azidas , Neoplasias da Mama/tratamento farmacológico , Caspase 3/metabolismo , Caspase 7/metabolismo , Indóis , Neoplasias Pulmonares/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Adulto , Idoso , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/enzimologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/enzimologia , Masculino , Pessoa de Meia-Idade
2.
Br J Cancer ; 113(6): 970-8, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26325105

RESUMO

BACKGROUND: The transforming growth factor-beta (TGF- ß) pathway has been implicated in proliferation, migration and invasion of various cancers. Endoglin is a TGF-ß accessory receptor that modulates signalling. We identified Endoglin as an epigenetically silenced tumour-suppressor gene in lung cancer by means of a genome-wide screening approach, then sought to characterise its effect on lung cancer progression. METHODS: Methylation microarray and RNA sequencing were carried out on lung cancer cell lines. Epigenetic silencing of Endoglin was confirmed by methylation and expression analyses. An expression vector and a 20-gene expression panel were used to evaluate Endoglin function. Pyrosequencing was carried out on two independent cohorts comprising 112 and 202 NSCLC cases, respectively, and the impact of Endoglin methylation on overall survival (OS) was evaluated. RESULTS: Methylation in the promoter region resulted in silencing of Endoglin, which could be reactivated by demethylation. Increased invasion coupled with altered EMT marker expression was observed in cell lines with an epithelial-like, but not those with a mesenchymal-like, profile when Endoglin was absent. Methylation was associated with decreased OS in stage I but not in stages II-III disease. CONCLUSIONS: We show that Endoglin is a common target of epigenetic silencing in lung cancer. We reveal a link between Endoglin silencing and EMT progression that might be associated with decreased survival in stage I disease.


Assuntos
Antígenos CD/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Inativação Gênica , Genes Supressores de Tumor , Neoplasias Pulmonares/genética , Receptores de Superfície Celular/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Progressão da Doença , Regulação para Baixo , Endoglina , Estudo de Associação Genômica Ampla , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Metilação , Regiões Promotoras Genéticas , Análise Serial de Proteínas , Análise de Sequência de DNA/métodos
3.
Kidney Int ; 85(5): 1137-50, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24429399

RESUMO

We have bred a Pkd1 floxed allele with a nestin-Cre expressing line to generate cystic mice with preserved glomerular filtration rate to address the pathogenesis of complex autosomal dominant polycystic kidney disease (ADPKD) phenotypes. Hypertension affects about 60% of these patients before loss of renal function, leading to significant morbimortality. Cystic mice were hypertensive at 5 and 13 weeks of age, a phenotype not seen in noncystic controls and Pkd1-haploinsufficient animals that do not develop renal cysts. Fractional sodium excretion was reduced in cystic mice at these ages. Angiotensinogen gene expression was higher in cystic than noncystic kidneys at 18 weeks, while ACE and the AT1 receptor were expressed in renal cyst epithelia. Cystic animals displayed increased renal cAMP, cell proliferation, and apoptosis. At 24 weeks, mean arterial pressure and fractional sodium excretion did not significantly differ between the cystic and noncystic groups, whereas cardiac mass increased in cystic mice. Renal concentrating deficit is also an early finding in ADPKD. Maximum urine osmolality and urine nitrite excretion were reduced in 10-13- and 24-week-old cystic mice, deficits not found in haploinsufficient and noncystic controls. A trend of higher plasma vasopressin was observed in cystic mice. Thus, cyst growth most probably plays a central role in early-stage ADPKD-associated hypertension, with activation of the intrarenal renin-angiotensin system as a key mechanism. Cyst expansion is also likely essential for the development of the concentrating deficit in this disease. Our findings are consistent with areas of reduced perfusion in the kidneys of patients with ADPKD.


Assuntos
Pressão Arterial , Proliferação de Células , Hipertensão/etiologia , Capacidade de Concentração Renal , Rim/metabolismo , Rim Policístico Autossômico Dominante/complicações , Canais de Cátion TRPP/deficiência , Animais , Apoptose , Pressão Arterial/genética , Biomarcadores/sangue , Biomarcadores/urina , Proliferação de Células/genética , Modelos Animais de Doenças , Progressão da Doença , Regulação da Expressão Gênica , Genótipo , Taxa de Filtração Glomerular , Hipertensão/genética , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Rim/patologia , Rim/fisiopatologia , Capacidade de Concentração Renal/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo , Rim Policístico Autossômico Dominante/patologia , Rim Policístico Autossômico Dominante/fisiopatologia , Sistema Renina-Angiotensina , Canais de Cátion TRPP/genética , Fatores de Tempo
4.
Br J Cancer ; 110(1): 208-13, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24169348

RESUMO

BACKGROUND: Carcinoma of unknown primary (CUP) is a clinical presentation with a poor prognosis. Inflammation-based prognostic systems are stage-independent prognostic predictors in various malignancies. We aimed to assess the accuracy of the modified Glasgow Prognostic Score (mGPS), neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR) as objective prognostic models in CUP. METHODS: We derived inflammatory scores in 60 consecutive CUP referrals to the Imperial College oncology unit between 1996 and 2011. Patient demographics, treatment and staging data and full blood profiles were collected. An independent cohort of 179 patients presenting to the Taipei Veterens Hospital between 2000 and 2009 were used as a 'validation' data set. Uni- and multivariate survival analysis was used to predict the overall survival (OS). RESULTS: Sixty patients were included: median age 61 (range: 33-86); 51% men; median OS 5.9 months (0.7-42.9); 88% with distant metastases. On univariate analysis NLR >5 (P=0.04) and mGPS (score 1-2) (P=0.03) correlated with OS. Multivariate analysis demonstrated significant hazard ratios for NLR; 2.02 (CI 1.0-4.1) (P=0.04) and mGPS; 1.52 (CI 1.0-2.3) (P=0.03). These findings were reinforced by analysis of the validation data. CONCLUSION: NLR and mGPS are independent, externally validated prognostic markers in CUP, with superior objectivity compared with performance status.


Assuntos
Inflamação/patologia , Neoplasias Primárias Desconhecidas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Estadiamento de Neoplasias , Neoplasias Primárias Desconhecidas/sangue , Prognóstico , Reprodutibilidade dos Testes
5.
Br J Cancer ; 110(8): 1930-5, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24667648

RESUMO

BACKGROUND: At least 30% of patients with primary resectable non-small cell lung cancer (NSCLC) will experience a relapse in their disease within 5 years following definitive treatment. Clinicopathological predictors have proved to be suboptimal in identifying high-risk patients. We aimed to establish whether inflammation-based scores offer an improved prognostic ability in terms of estimating overall (OS) and recurrence-free survival (RFS) in a cohort of operable, early-stage NSCLC patients. METHODS: Clinicopathological, demographic and treatment data were collected prospectively for 220 patients operated for primary NSCLC at the Hammersmith Hospital from 2004 to 2011. Pretreatment modified Glasgow Prognostic Score (mGPS), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were tested together with established prognostic factors in uni- and multivariate Cox regression analyses of OS and RFS. RESULTS: Half of the patients were male, with a median age of 65. A total of 57% were classified as stage I with adenocarcinoma being the most prevalent subtype (60%). Univariate analyses of survival revealed stage (P<0.001), grade (P=0.02), lymphovascular (LVI, P=0.001), visceral pleural invasion (VPI, P=0.003), mGPS (P=0.02) and NLR (P=0.04) as predictors of OS, with stage (P<0.001), VPI (P=0.02) and NLR (P=0.002) being confirmed as independent prognostic factors on multivariate analyses. Patients with more advanced stage (P<0.001) and LVI (P=0.008) had significantly shorter RFS. CONCLUSIONS: An elevated NLR identifies operable NSCLC patients with a poor prognostic outlook and an OS difference of almost 2 years compared to those with a normal score at diagnosis. Our study validates the clinical utility of the NLR in early-stage NSCLC.


Assuntos
Contagem de Células Sanguíneas , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Inflamação/patologia , Recidiva Local de Neoplasia/diagnóstico , Idoso , Plaquetas/patologia , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Inflamação/sangue , Inflamação/diagnóstico , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/patologia , Neutrófilos/patologia , Prognóstico , Modelos de Riscos Proporcionais
6.
Br J Cancer ; 108(3): 621-8, 2013 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-23361052

RESUMO

BACKGROUND: Recent preclinical studies identified Axl, a tyrosine kinase receptor implicated in tumour progression and epithelial-to-mesenchymal transition, as a putative therapeutic target in malignant pleural mesothelioma (MPM), an invariably fatal malignancy with limited treatment options. Here, we studied the expression of Axl and its ligand Gas-6 (growth arrest signal-6) in primary specimens of MPM, correlating their expression levels with tumour phenotype and clinical outcomes. METHODS: Two independent cohorts of consecutive patients diagnosed with MPM were studied: a derivation cohort composed of 63 cases and a validation set of 35 cases. Clinical variables including patients' demographics, tumour stage, histotype, performance status (PS), Axl and Gas-6 staining were tested for predicting overall survival (OS) using univariate and multivariate analyses. RESULTS: In the derivation cohort, Axl (P=0.001) but not Gas-6 overexpression (P=0.35) emerged as a univariate prognostic factor for OS, together with stage (P=0.05), PS (P<0.001) hypoalbuminaemia (P<0.001) and anaemia (P<0.001). Multivariate analyses confirmed Axl overexpression (P=0.01), PS (P=0.01), hypoalbuminaemia (P<0.001) and anaemia (P=0.04) as independent predictors of OS. The prognostic role of Axl overexpression was externally validated in an independent cohort (P=0.03). CONCLUSION: Overexpression of Axl is found in the majority of MPM specimens and influences patient's survival independently from other established prognostic factors. Such information may support patient selection for future trials.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Mesotelioma/patologia , Neoplasias Pleurais/patologia , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Masculino , Mesotelioma/metabolismo , Mesotelioma/mortalidade , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Neoplasias Pleurais/metabolismo , Neoplasias Pleurais/mortalidade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Receptor Tirosina Quinase Axl
8.
Cytopathology ; 24(3): 150-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23711181

RESUMO

This review article discusses the role of endoscopic ultrasound-guided fine needle aspiration (EUS FNA) cytology in the clinical management of patients with pancreatic tumours in the setting of a multidisciplinary team (MDT). The commonest diagnosis encountered is pancreatic adenocarcinoma, which is seldom diagnosed early enough for surgical resection. Thus, cytology is likely to be the only form of diagnosis in the majority of cases. Nevertheless, about half the lesions discussed at the MDT meeting are lesions other than primary adenocarcinoma and a wide differential diagnosis must be considered in order to identify tumours, including neuroendocrine tumours, that are amenable to surgical resection. Cytology is not always definitive and the diagnosis may be helped by categorizing results according to whether they are malignant, suspicious, atypical/indeterminate, benign or inadequate. Discussion at MDT meetings and correlation with clinical and imaging findings along with review of cytology slides may allow equivocal results to be clarified before treatment is decided. Inadequate cytology results are avoided by rapid on-site evaluation of slides; although this is cost-effective in terms of overall patient care, attendance of cytopathologists on-site may not be feasible. At Imperial College NHS Trust, specially trained biomedical scientists successfully carry out rapid on-site evaluation.


Assuntos
Citodiagnóstico , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Tumores Neuroendócrinos/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Humanos , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia
9.
Schweiz Arch Tierheilkd ; 153(9): 405-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21866514
10.
Clin Radiol ; 65(8): 642-50, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20599067

RESUMO

Sarcoidosis has a wide spectrum of appearances within the thorax. This review will discuss and illustrate the range of pulmonary manifestations on high-resolution computed tomography and chest radiography, concentrating on atypical features and examples of sarcoidosis mimicking other lung diseases. All included cases have been histologically confirmed. Such variable imaging appearances should alert the radiologist to consider sarcoidosis as a differential diagnosis in the context of interstitial lung disease.


Assuntos
Sarcoidose Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Diagnóstico Diferencial , Feminino , Humanos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/patologia , Masculino , Intensificação de Imagem Radiográfica/métodos , Sarcoidose Pulmonar/patologia
11.
Phys Rev Lett ; 112(4): 049702, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24580499
12.
Cardiovasc Ultrasound ; 7: 8, 2009 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-19216782

RESUMO

BACKGROUND: Recent advances in technology have provided the opportunity for off-line analysis of digital video-clips of two-dimensional (2-D) echocardiographic images. Commercially available software that follows the motion of cardiac structures during cardiac cycle computes both regional and global velocity, strain, and strain rate (SR). The present study aims to evaluate the clinical applicability of the software based on the tracking algorithm feature (studied for cardiology purposes) and to derive the reference values for longitudinal and circumferential strain and SR of the left ventricle in a normal population of children and young adults. METHODS: 45 healthy volunteers (30 adults: 19 male, 11 female, mean age 37 +/- 6 years; 15 children: 8 male, 7 female, mean age 8 +/- 2 years) underwent transthoracic echocardiographic examination; 2D cine-loops recordings of apical 4-four 4-chamber (4C) and 2-chamber (2C) views and short axis views were stored for off-line analysis. Computer analyses were performed using specific software relying on the algorithm of optical flow analysis, specifically designed to track the endocardial border, installed on a Windows based computer workstation. Inter and intra-observer variability was assessed. RESULTS: The feasibility of measurements obtained with tissue tracking system was higher in apical view (100% for systolic events; 64% for diastolic events) than in short axis view (70% for systolic events; 52% for diastolic events). Longitudinal systolic velocity decreased from base to apex in all subjects (5.22 +/- 1.01 vs. 1.20 +/- 0.88; p < 0.0001). Longitudinal strain and SR significantly increased from base to apex in all subjects (-12.95 +/- 6.79 vs. -14.87 +/- 6.78; p = 0.002; -0.72 +/- 0.39 vs. -0.94 +/- 0.48, p = 0.0001, respectively). Similarly, circumferential strain and SR increased from base to apex (-21.32 +/- 5.15 vs. -27.02 +/- 5.88, p = 0.002; -1.51 +/- 0.37 vs. -1.95 +/- 0.57, p = 0.003, respectively). Values of global systolic SR, both longitudinal and circumferential, were significantly higher in children than in adults (-1.3 +/- 0.2, vs. -1.11 +/- 0.2, p = 0.006; -1.9 +/- 0.6 vs. -1.6 +/- 0.5, p = 0.0265, respectively). No significant differences in longitudinal and circumferential systolic velocities were identified for any segment when comparing adults with children. CONCLUSION: This 2D based tissue tracking system used for computation is reliable and applicable in adults and children particularly for systolic events. Measured with this technology, we have established reference values for myocardial velocity, Strain and SR for both young adults and children.


Assuntos
Envelhecimento , Ecocardiografia Doppler/métodos , Ecocardiografia Doppler/normas , Software , Adulto , Algoritmos , Criança , Diástole , Ecocardiografia Doppler/estatística & dados numéricos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Valores de Referência , Sístole
13.
J Phys Condens Matter ; 21(24): 245302, 2009 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21693942

RESUMO

We present a study of the phononic thermal conductivity of isotopically disordered carbon nanotubes. In particular, the behaviour of the thermal conductivity as a function of the system length is investigated, using Green's function techniques to compute the transmission across the system. The method is implemented using linear scaling algorithms, which allow us to reach systems of lengths up to L = 2.5 µm (with up to 200 000 atoms). As for 1D systems, it is observed that the conductivity diverges with the system size L. We also observe a dramatic decrease of the thermal conductance for systems of experimental sizes (roughly 80% at room temperature for L = 2.5 µm), when a large fraction of isotopic disorder is introduced. The results obtained with Green's function techniques are compared to results obtained with a Boltzmann description of thermal transport. There is a good agreement between both approaches for systems of experimental sizes, even in the presence of Anderson localization. This is particularly interesting since the computation of the transmission using Boltzmann's equation is much less computationally expensive, so that larger systems may be studied with this method.

14.
Nat Commun ; 9(1): 308, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29358728

RESUMO

The equilibrium optical phonons of graphene are well characterized in terms of anharmonicity and electron-phonon interactions; however, their non-equilibrium properties in the presence of hot charge carriers are still not fully explored. Here we study the Raman spectrum of graphene under ultrafast laser excitation with 3 ps pulses, which trade off between impulsive stimulation and spectral resolution. We localize energy into hot carriers, generating non-equilibrium temperatures in the ~1700-3100 K range, far exceeding that of the phonon bath, while simultaneously detecting the Raman response. The linewidths of both G and 2D peaks show an increase as function of the electronic temperature. We explain this as a result of the Dirac cones' broadening and electron-phonon scattering in the highly excited transient regime, important for the emerging field of graphene-based photonics and optoelectronics.

16.
J Magn Reson ; 187(1): 131-40, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17481933

RESUMO

The complete set of NMR parameters for (17)O enriched phenylphosphinic acid C(6)H(5)HP( *)O(*OH) is calculated from first principles by using the Gauge Including Projected Augmented Wave (GIPAW) approach [C.J. Pickard, F. Mauri, All-electron magnetic response with pseudopotentials: NMR chemical shifts, Phys. Rev. B 63 (2001) 245101/1-245101/13]. The analysis goes beyond the successful assignment of the spectra for all nuclei ((1)H, (13)C, (17)O, (31)P), as: (i) the (1)H CSA (chemical shift anisotropy) tensors (magnitude and orientation) have been interpreted in terms of H bonding and internuclear distances. (ii) CSA/dipolar local field correlation experiments have allowed the orientation of the direct P-H bond direction in the (31)P CSA tensor to be determined. Experimental and calculated data were compared. (iii) The overestimation of the calculated (31)P CSA has been explained by local molecular reorientation and confirmed by low temperature static (1)H-->(31)P CP experiments.


Assuntos
Ácidos Fosfínicos/química , Algoritmos , Anisotropia , Simulação por Computador , Durapatita/química , Campos Eletromagnéticos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Isótopos de Oxigênio
17.
J Phys Condens Matter ; 29(46): 465901, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29064822

RESUMO

Quantum EXPRESSO is an integrated suite of open-source computer codes for quantum simulations of materials using state-of-the-art electronic-structure techniques, based on density-functional theory, density-functional perturbation theory, and many-body perturbation theory, within the plane-wave pseudopotential and projector-augmented-wave approaches. Quantum EXPRESSO owes its popularity to the wide variety of properties and processes it allows to simulate, to its performance on an increasingly broad array of hardware architectures, and to a community of researchers that rely on its capabilities as a core open-source development platform to implement their ideas. In this paper we describe recent extensions and improvements, covering new methodologies and property calculators, improved parallelization, code modularization, and extended interoperability both within the distribution and with external software.

18.
Biochim Biophys Acta ; 1078(1): 63-7, 1991 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-2049384

RESUMO

Coelomic cells from the sea cucumber Caudina (Molpadia) arenicola contain four major globins, A, B, C and D. The hemoglobins from this organism show unusual ligand-linked dissociation properties. The complete amino acid sequence of the D globin has been established. It is N-acetylated, consists of 158 residues and has a 10 amino acid N-terminal extension similar to that found in some other invertebrate globins. The C. arenicola D globin has an equal sequence identity (28%) with both alpha and beta human globins and as anticipated, is more closely related to these vertebrate proteins than are molluscan globins. The C. arenicola D globin shows a 59% identity with the globin I from the sea cucumber Paracaudina chilensis. The availability of the C. arenicola D globin sequence will aid the X-ray analysis of this protein and facilitate an understanding of the changes in subunit interactions that occur with cooperative ligand binding.


Assuntos
Globinas/química , Pepinos-do-Mar/análise , Sequência de Aminoácidos , Animais , Humanos , Invertebrados , Dados de Sequência Molecular , Filogenia , Homologia de Sequência do Ácido Nucleico , Vertebrados
19.
J Am Coll Cardiol ; 24(3): 600-7, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8077527

RESUMO

OBJECTIVES: This analysis aimed to evaluate in a large patient cohort the relation between ST segment alterations after fibrinolytic therapy for acute myocardial infarction and 1) the combined end point of in-hospital mortality plus clinical congestive heart failure or extensive left ventricular damage, and 2) mortality 30 and 180 days after randomization. BACKGROUND: Angina relief, enzyme release acceleration and ST segment normalization are related to coronary artery reperfusion and prognosis. Electrocardiographic (ECG) evaluation before and after fibrinolytic drug administration has been used to predict short- and long-term clinical outcome in acute myocardial infarction. METHODS: Patients enrolled in the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico (GISSI-2) trial underwent a standard ECG on admission and after 4 h of alteplase or streptokinase therapy; 7,426 recordings were suitable for ST segment analysis. A decrease > or = 50% in the sum of ST segment elevation in all ECG leads was adopted as the cutoff for predicting coronary artery patency. Recanalization was deemed to have occurred in 4,951 patients (group A) versus 2,475 patients without reperfusion (group B). RESULTS: Group A patients experienced a lower incidence of the combined end point than did group B patients (16.2% vs. 22.9%, respectively), as well as of all its components (death, clinical heart failure, ejection fraction < 35%, injured myocardial segment > 45%, QRS score > 10). Thirty- and 180-day mortality rates were lower in group A than group B (3.5% and 5.7% vs. 7.4% and 9.9%, respectively); relative risk (Cox) was 0.46 (95% confidence interval [CI] 0.37 to 0.57) for 30-day and 0.58 (95% CI 0.48 to 0.70) for 180-day mortality. Patients in group A had significantly less ventricular fibrillation and sustained ventricular tachycardia but more ischemic episodes (early recurrent angina plus myocardial infarction recurrence). CONCLUSIONS: A simple, inexpensive instrumental evaluation, unaffected by different epidemiologic and clinical characteristics of the population analyzed, can allow early assessment of the effectiveness of fibrinolytic treatment with respect to the main clinical outcomes.


Assuntos
Eletrocardiografia , Infarto do Miocárdio/tratamento farmacológico , Terapia Trombolítica , Idoso , Estudos de Coortes , Quimioterapia Combinada , Feminino , Seguimentos , Heparina/uso terapêutico , Humanos , Itália , Masculino , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Valor Preditivo dos Testes , Prognóstico , Estreptoquinase/uso terapêutico , Taxa de Sobrevida , Ativador de Plasminogênio Tecidual/uso terapêutico
20.
J Am Coll Cardiol ; 24(3): 608-15, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8077528

RESUMO

OBJECTIVES: This study was designed to reassess the prediction of recurrent nonfatal myocardial infarction in patients recovering from acute myocardial infarction after thrombolysis. BACKGROUND: Recurrent nonfatal myocardial infarction is a strong and independent predictor of subsequent mortality. Current knowledge of risk factors for nonfatal reinfarction is still largely based on data gathered before the advent of thrombolysis. Thus, this prospective study was planned to identify harbinger of nonfatal reinfarction in the postinfarction patients of the multicenter Grouppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico (GISSI-2) trial. METHODS: Predictors of nonfatal reinfarction at 6 months were analyzed by multivariate technique (Cox model) in 8,907 GISSI-2 survivors of myocardial infarction with clinical follow-up, relying on a set of prespecified variables reflecting residual ischemia, left ventricular failure or dysfunction, complex ventricular arrhythmias, comorbidity as well as demographic and historical factors. RESULTS: The postdischarge to 6-month incidence rate of nonfatal reinfarction was 2.5%. Independent predictors of nonfatal reinfarction were cardiac ineligibility for exercise test (relative risk 2.97, 95% confidence interval [CI] 1.98 to 4.45), previous myocardial infarction (relative risk 1.70, 95% CI 1.22 to 2.36) and angina at follow-up (relative risk 1.50, 95% CI 1.10 to 2.04). On further multivariate analysis, performed in 6,580 patients with both echocardiographic and electrocardiographic monitoring data available, a history of angina emerged as an additional risk predictor (relative risk 1.58, 95% CI 1.10 to 2.25). CONCLUSIONS: The 6-month incidence of nonfatal reinfarction is rather low in survivors of myocardial infarction after thrombolysis. Cardiac ineligibility for exercise testing and a history of coronary artery disease are risk predictors. Recurrent nonfatal infarction is not predictable by qualitative variables reflecting residual ischemia, except by postdischarge angina. Prediction of nonfatal reinfarction appears less accurate than prediction of mortality, as almost 50% of reinfarctions occur in patients without any of the identified risk factors.


Assuntos
Infarto do Miocárdio/tratamento farmacológico , Terapia Trombolítica , Análise de Variância , Angina Pectoris/etiologia , Teste de Esforço , Feminino , Seguimentos , Humanos , Sistemas de Informação , Itália , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Recidiva , Fatores de Risco , Estreptoquinase/uso terapêutico , Ativador de Plasminogênio Tecidual/uso terapêutico
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