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1.
Clin Radiol ; 79(4): e532-e538, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38242805

RESUMO

AIM: To evaluate the prevalence of coronary artery calcification (CAC) on non-contrast computed tomography (CT) of the thorax in patients with interstitial lung disease (ILD), assess consistency of CAC reporting and assess incidence of subsequent cardiac events. MATERIALS AND METHODS: Patients with known interstitial lung disease who underwent a CT thorax over a 2-year period were retrospectively reviewed. Presence of CAC was assessed using a visual scale for CAC reporting and graded as mild, moderate, or severe by two cardiothoracic radiologists. CT reports were reviewed to determine if presence of CAC had been described. Electronic medical records were reviewed for any subsequent cardiothoracic events from the date of the CT thorax to present. RESULTS: 254 patients were included in the analysis (54.7% men; mean age 59.9 yo). 43.7% had CAC on their CT thorax; however, in 87.3% of those, reports did not comment on its presence. 8 patients had cardiac events; 7 of them had CAC on CT although only in 1 case this was reported. Global CAC and LAD CAC Patients with cardiac events had a significantly higher global CAC (p=0.016) and LAD CAC (p=0.048) when compared to patients without. CONCLUSION: We demonstrated a high prevalence of CAC in ILD patients and its significant association with adverse cardiac events. Unfortunately, CAC on CT thorax is still largely unreported. As per recent BSCI/BSCCT and BSTI guidelines, reporting of CAC should become part of routine practice, as may prompt prevention and impact on patients outcome.


Assuntos
Doença da Artéria Coronariana , Doenças Pulmonares Intersticiais , Calcificação Vascular , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Vasos Coronários , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Tomografia Computadorizada por Raios X/métodos , Tórax , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/epidemiologia , Doenças Pulmonares Intersticiais/complicações , Calcificação Vascular/complicações , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Angiografia Coronária/métodos , Fatores de Risco
2.
Clin Radiol ; 78(5): 315-322, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36804271

RESUMO

Minimally invasive interventional techniques are being utilised more frequently in the management of acute and chronic pulmonary emboli; however, robust clinical evidence is only emerging for the utilisation of these techniques. Hence, there is a need for a robust mechanism of patient selection and careful consideration of the benefits and risks of the interventions. In this review, we discuss the risk stratification mechanisms; the role of the multidisciplinary pulmonary embolism response team to support decision-making; and describe the various commonly used interventional techniques and how these can be integrated into treatment strategies for the benefit of our patients.


Assuntos
Embolia Pulmonar , Terapia Trombolítica , Humanos , Terapia Trombolítica/métodos , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/cirurgia , Seleção de Pacientes
3.
Am J Physiol Heart Circ Physiol ; 320(3): H923-H941, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33356960

RESUMO

With each heartbeat, the right ventricle (RV) inputs blood into the pulmonary vascular (PV) compartment, which conducts blood through the lungs at low pressure and concurrently fills the left atrium (LA) for output to the systemic circulation. This overall hemodynamic function of the integrated RV-PV-LA unit is determined by complex interactions between the components that vary over the cardiac cycle but are often assessed in terms of mean pressure and flow. Exercise challenges these hemodynamic interactions as cardiac filling increases, stroke volume augments, and cycle length decreases, with PV pressures ultimately increasing in association with cardiac output. Recent cardiopulmonary exercise hemodynamic studies have enriched the available data from healthy adults, yielded insight into the underlying mechanisms that modify the PV pressure-flow relationship, and better delineated the normal limits of healthy responses to exercise. This review will examine hemodynamic function of the RV-PV-LA unit using the two-element Windkessel model for the pulmonary circulation. It will focus on acute PV and LA responses that accommodate increased RV output during exercise, including PV recruitment and distension and LA reservoir expansion, and the integrated mean pressure-flow response to exercise in healthy adults. Finally, it will consider how these responses may be impacted by age-related remodeling and modified by sex-related cardiopulmonary differences. Studying the determinants and recognizing the normal limits of PV pressure-flow relations during exercise will improve our understanding of cardiopulmonary mechanisms that facilitate or limit exercise.


Assuntos
Função do Átrio Esquerdo , Exercício Físico , Coração/fisiologia , Hemodinâmica , Pulmão/irrigação sanguínea , Circulação Pulmonar , Função Ventricular Direita , Adaptação Fisiológica , Fatores Etários , Feminino , Voluntários Saudáveis , Humanos , Masculino , Modelos Cardiovasculares , Fatores Sexuais , Fatores de Tempo
4.
Phys Rev Lett ; 126(24): 242301, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213947

RESUMO

Using combined data from the Relativistic Heavy Ion and Large Hadron Colliders, we constrain the shear and bulk viscosities of quark-gluon plasma (QGP) at temperatures of ∼150-350 MeV. We use Bayesian inference to translate experimental and theoretical uncertainties into probabilistic constraints for the viscosities. With Bayesian model averaging we propagate an estimate of the model uncertainty generated by the transition from hydrodynamics to hadron transport in the plasma's final evolution stage, providing the most reliable phenomenological constraints to date on the QGP viscosities.

5.
Clin Radiol ; 75(10): 795.e1-795.e5, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778329

RESUMO

AIM: To evaluate the incidence of pulmonary ischaemia in COVID-19 patients on extracorporeal membrane oxygenation (ECMO), and its correlation with pulmonary artery thrombosis. MATERIALS AND METHODS: Computed tomography (CT) thorax of all patients receiving ECMO with proven COVID-19 pneumonitis between March and May 2020 were analysed for the presence and extension of pulmonary thromboembolic disease. RESULTS: Fifty-one patients were reviewed. The mean (range) age of 45 (26-66) years; 38/51 (74.5%) were men. All patients had severe COVID-19 pneumonitis, and 18/51 (35.3%) had macroscopic thrombosis (15 with associated ischaemia); however, 13/51 (25.5%) patients had ischaemia without associated thrombus. CONCLUSION: The majority of patients with COVID-19 who received ECMO had areas of ischaemia within consolidated lungs, almost half of these without subtending pulmonary artery thrombosis. Although the prognostic significance of these findings is unclear, they are highly suggestive of lung ischaemia due to isolated microvascular immune thrombosis.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Infecções por Coronavirus/terapia , Oxigenação por Membrana Extracorpórea/métodos , Pneumonia Viral/complicações , Pneumonia Viral/terapia , Embolia Pulmonar/complicações , Adulto , Idoso , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/patologia , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/patologia , Embolia Pulmonar/patologia , SARS-CoV-2 , Tomografia Computadorizada por Raios X
6.
Hong Kong Med J ; 25(3): 209-215, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31178436

RESUMO

OBJECTIVE: To compare the clinical outcomes and pathological findings of transperineal ultrasound-guided prostate biopsy (TPUSPB) and transrectal ultrasound-guided prostate biopsy (TRUSPB) in a secondary referral hospital. METHODS: This was a retrospective study of 100 TPUSPBs and 100 TRUSPBs performed in our centre. Pre-biopsy patient parameters (eg, patient age, clinical staging, serum prostate-specific antigen [PSA] level, prostate size, and PSA density), as well as pathological results and 30-day complication and readmission rates, were retrieved from the patients' medical records and compared between the two groups. RESULTS: One hundred TPUSPBs performed from January 2018 to May 2018 and 100 TRUSPBs performed from January 2016 to April 2016 were included for analysis. Mean age did not significantly differ between the groups. The TPUSPB group had a higher mean PSA level, smaller prostate size, and higher PSA density, compared with the TRUSPB group. The overall prostate cancer detection rate was similar between the TPUSPB and TRUSPB groups (35% vs 25%, P=0.123). There were no significant differences between the groups in prostate cancer detection rates after stratification according to PSA density and clinical staging. With respect to complications, no patients developed fever in the TPUSPB group, while 4% of patients in the TRUSPB group had fever and required at least 1-week admission for intravenous antibiotic administration. CONCLUSION: For prostate biopsy, TPUSPB is safer, with no infection complications, and has similar prostate cancer detection rate compared with TRUSPB.


Assuntos
Neoplasias da Próstata/patologia , Reto , Ultrassonografia de Intervenção , Idoso , Biópsia/métodos , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos
7.
Eur Radiol ; 27(9): 3635-3646, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28130610

RESUMO

BACKGROUND: Hypersensitivity pneumonitis (HP) has a variable clinical course. Modelling of quantitative CALIPER-derived CT data can identify distinct disease phenotypes. Mortality prediction using CALIPER analysis was compared to the interstitial lung disease gender, age, physiology (ILD-GAP) outcome model. METHODS: CALIPER CT analysis of parenchymal patterns in 98 consecutive HP patients was compared to visual CT scoring by two radiologists. Functional indices including forced vital capacity (FVC) and diffusion capacity for carbon monoxide (DLco) in univariate and multivariate Cox mortality models. Automated stratification of CALIPER scores was evaluated against outcome models. RESULTS: Univariate predictors of mortality included visual and CALIPER CT fibrotic patterns, and all functional indices. Multivariate analyses identified only two independent predictors of mortality: CALIPER reticular pattern (p = 0.001) and DLco (p < 0.0001). Automated stratification distinguished three distinct HP groups (log-rank test p < 0.0001). Substitution of automated stratified groups for FVC and DLco in the ILD-GAP model demonstrated no loss of model strength (C-Index = 0.73 for both models). Model strength improved when automated stratified groups were combined with the ILD-GAP model (C-Index = 0.77). CONCLUSIONS: CALIPER-derived variables are the strongest CT predictors of mortality in HP. Automated CT stratification is equivalent to functional indices in the ILD-GAP model for predicting outcome in HP. KEY POINTS: • Computer CT analysis better predicts mortality than visual CT analysis in HP. • Quantitative CT analysis is equivalent to functional indices for prognostication in HP. • Prognostication using the ILD-GAP model improves when combined with quantitative CT analysis.


Assuntos
Alveolite Alérgica Extrínseca/diagnóstico por imagem , Idoso , Alveolite Alérgica Extrínseca/mortalidade , Alveolite Alérgica Extrínseca/fisiopatologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Londres/epidemiologia , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/mortalidade , Doenças Pulmonares Intersticiais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Capacidade de Difusão Pulmonar/fisiologia , Testes de Função Respiratória , Tomografia Computadorizada por Raios X/métodos , Capacidade Vital/fisiologia
8.
Clin Radiol ; 72(11): 925-929, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28784319

RESUMO

AIM: To evaluate the impact of inspiratory effort and emphysema on reproducibility of pulmonary nodule volumetry. MATERIALS AND METHODS: Eighty-eight nodules in 24 patients with emphysema were studied retrospectively. All patients had undergone volumetric inspiratory and end-expiratory thoracic computed tomography (CT) for consideration of bronchoscopic lung volume reduction. Inspiratory and expiratory nodule volumes were measured using commercially available software. Local emphysema extent was established by analysing a segmentation area extended circumferentially around each nodule (quantified as percent of lung with density of -950 HU or less). Lung volumes were established using the same software. Differences in inspiratory and expiratory nodule volumes were illustrated using the Bland-Altman test. The influences of percentage reduction in lung volume at expiration, local emphysema extent, and nodule size on nodule volume variability were tested with multiple linear regression. RESULTS: The majority of nodules (59/88 [67%]) showed an increased volume at expiration. Mean difference in nodule volume between expiration and inspiration was +7.5% (95% confidence interval: -24.1, 39.1%). No relationships were demonstrated between nodule volume variability and emphysema extent, degree of expiration, or nodule size. CONCLUSION: Expiration causes a modest increase in volumetry-derived nodule volumes; however, the effect is unpredictable. Local emphysema extent had no significant effect on volume variability in the present cohort.


Assuntos
Inalação/fisiologia , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/patologia , Enfisema Pulmonar/patologia , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/complicações , Enfisema Pulmonar/complicações , Reprodutibilidade dos Testes , Testes de Função Respiratória , Estudos Retrospectivos
11.
Proc Natl Acad Sci U S A ; 110(15): 5834-9, 2013 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-23530249

RESUMO

Cancer is a complex disease with a range of genetic and biochemical markers within and among tumors, but a general tumor characteristic is extracellular acidity, which is associated with tumor growth and development. Acidosis could be a universal marker for cancer imaging and the delivery of therapeutic molecules, but its promise as a cancer biomarker has not been fully realized in the clinic. We have discovered a unique approach for the targeting of acidic tissue using the pH-sensitive folding and transmembrane insertion of pH (low) insertion peptide (pHLIP). The essence of the molecular mechanism has been elucidated, but the principles of design need to be understood for optimal clinical applications. Here, we report on a library of 16 rationally designed pHLIP variants. We show how the tuning of the biophysical properties of peptide-lipid bilayer interactions alters tumor targeting, distribution in organs, and blood clearance. Lead compounds for PET/single photon emission computed tomography and fluorescence imaging/MRI were identified, and targeting specificity was shown by use of noninserting variants. Finally, we present our current understanding of the main principles of pHLIP design.


Assuntos
Proteínas de Membrana/química , Neoplasias/patologia , Peptídeos/química , Sequência de Aminoácidos , Animais , Membrana Celular/metabolismo , Feminino , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Bicamadas Lipídicas/química , Imageamento por Ressonância Magnética , Camundongos , Camundongos Nus , Microscopia de Fluorescência , Dados de Sequência Molecular , Transplante de Neoplasias , Neoplasias/metabolismo , Dobramento de Proteína , Termodinâmica , Tomografia Computadorizada de Emissão de Fóton Único
15.
Clin Radiol ; 70(6): 644-53, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25770022

RESUMO

We present a review of head and neck adenoid cystic carcinoma (ACC). Imaging features of the primary tumour, patterns of locoregional spread, and distant metastasis with emphasis on perineural extension and imaging pitfalls are discussed with illustrated examples.


Assuntos
Carcinoma Adenoide Cístico/patologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias dos Nervos Cranianos/patologia , Músculos Faciais/inervação , Doenças do Nervo Facial/patologia , Humanos , Imageamento por Ressonância Magnética , Invasividade Neoplásica , Doenças do Nervo Trigêmeo/patologia
16.
Hong Kong Med J ; 21(1): 77-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25686707

RESUMO

Synthetic fibre granuloma of the conjunctiva, sometimes known as 'teddy bear granuloma', results from granulomatous foreign body reaction of the conjunctiva to synthetic fibres. It is often an incidental finding, most commonly found in children, is unilateral, and occurs in the lower eyelid. We present here, what we believe is the first reported case of synthetic fibre conjunctival granuloma in Hong Kong, together with a review of the condition. An awareness of this clinical entity allows early and accurate diagnosis and early treatment.


Assuntos
Túnica Conjuntiva , Granuloma de Corpo Estranho/patologia , Criança , Feminino , Hong Kong , Humanos
17.
Epidemiol Infect ; 142(10): 2075-84, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24892423

RESUMO

We studied the association between drinking water, agriculture and sporadic human campylobacteriosis in one region of British Columbia (BC), Canada. We compared 2992 cases of campylobacteriosis to 4816 cases of other reportable enteric diseases in 2005-2009 using multivariate regression. Cases were geocoded and assigned drinking water source, rural/urban environment and socioeconomic status (SES) according to the location of their residence using geographical information systems analysis methods. The odds of campylobacteriosis compared to enteric disease controls were higher for individuals serviced by private wells than municipal surface water systems (odds ratio 1·4, 95% confidence interval 1·1-1·8). In rural settings, the odds of campylobacteriosis were higher in November (P = 0·014). The odds of campylobacteriosis were higher in individuals aged ⩾15 years, especially in those with higher SES. In this region of BC, campylobacteriosis risk, compared to other enteric diseases, seems to be mediated by vulnerable drinking water sources and rural factors. Consideration should be given to further support well-water users and to further study the microbiological impact of agriculture on water.


Assuntos
Agricultura/estatística & dados numéricos , Infecções por Campylobacter/epidemiologia , Água Potável , Enterite/epidemiologia , População Rural/estatística & dados numéricos , Classe Social , População Urbana/estatística & dados numéricos , Abastecimento de Água/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Amebíase/epidemiologia , Colúmbia Britânica/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Criptosporidiose/epidemiologia , Ciclosporíase/epidemiologia , Disenteria Bacilar/epidemiologia , Enterite/microbiologia , Infecções por Escherichia coli/epidemiologia , Feminino , Mapeamento Geográfico , Giardíase/epidemiologia , Humanos , Lactente , Listeriose/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infecções por Salmonella/epidemiologia , Vibrioses/epidemiologia , Yersiniose/epidemiologia , Adulto Jovem
19.
Biophys J ; 102(8): 1846-55, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22768940

RESUMO

The membrane-associated folding/unfolding of pH (low) insertion peptide (pHLIP) provides an opportunity to study how sequence variations influence the kinetics and pathway of peptide insertion into bilayers. Here, we present the results of steady-state and kinetics investigations of several pHLIP variants with different numbers of charged residues, with attached polar cargoes at the peptide's membrane-inserting end, and with three single-Trp variants placed at the beginning, middle, and end of the transmembrane helix. Each pHLIP variant exhibits a pH-dependent interaction with a lipid bilayer. Although the number of protonatable residues at the inserting end does not affect the ultimate formation of helical structure across a membrane, it correlates with the time for peptide insertion, the number of intermediate states on the folding pathway, and the rates of unfolding and exit. The presence of polar cargoes at the peptide's inserting end leads to the appearance of intermediate states on the insertion pathway. Cargo polarity correlates with a decrease of the insertion rate. We conclude that the existence of intermediate states on the folding and unfolding pathways is not mandatory and, in the simple case of a polypeptide with a noncharged and nonpolar inserting end, the folding and unfolding appears as an all-or-none transition. We propose a model for membrane-associated insertion/folding and exit/unfolding and discuss the importance of these observations for the design of new delivery agents for direct translocation of polar therapeutic and diagnostic cargo molecules across cellular membranes.


Assuntos
Membrana Celular/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Sequência de Aminoácidos , Membrana Celular/química , Concentração de Íons de Hidrogênio , Cinética , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Lipossomos/química , Lipossomos/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Estrutura Secundária de Proteína , Desdobramento de Proteína , Temperatura , Termodinâmica
20.
Hong Kong Med J ; 18(4): 338-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22865180

RESUMO

Sclerosing stromal tumour of the ovary is rare. Patients present with menstrual irregularities, pelvic pain, abdominal distension, and presence of a large pelvic mass during their twenties or thirties. We report a rare case of an ovarian sclerosing stromal tumour with an atypical presentation, in that it gave rise to recurrent postmenopausal bleeding.


Assuntos
Histerectomia , Neoplasias Ovarianas/complicações , Hemorragia Uterina/cirurgia , Feminino , História do Século XVII , Humanos , Neoplasias Ovarianas/patologia , Pós-Menopausa , Recidiva , Esclerose , Hemorragia Uterina/etiologia
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