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1.
Artigo em Inglês | MEDLINE | ID: mdl-38759116

RESUMO

OBJECTIVES: Measures of right heart size and function are prognostic in systemic sclerosis-associated pulmonary hypertension (SSc-PH), but the importance of myocardial tissue characterisation remains unclear. We aimed to investigate the predictive potential and interaction of cardiovascular magnetic resonance (CMR) myocardial tissue characterisation and right heart size and function in SSc-PH. METHODS: A retrospective, single-centre, observational study of 148 SSc-PH patients confirmed by right heart catheterization who underwent clinically-indicated CMR including native myocardial T1 and T2 mapping from 2016 to 2023 was performed. RESULTS: Sixty-six (45%) patients died during follow-up (median 3.5 years, range 0.1-7.3). Patients who died were older (65 vs 60 years, p= 0.035) with more dilated (RVEDVi and RVESVi, p< 0.001), hypertrophied (RVMi, p= 0.013) and impaired (RVEF, p< 0.001) right ventricles, more dilated right atria (RAi, p= 0.043) and higher native myocardial T1 (p< 0.001).After adjustment for age, RVESVi (p = 0.0023) and native T1 (p = 0.0024) were independent predictors of all-cause mortality. Both RVESVi and native T1 remained independently predictive after adjusting for age and PH subtype (RVESVi p < 0.001, T1 p = 0.0056). Optimal prognostic thresholds for RVESVi and native T1 were ≤38 mL/m2 and ≤1119 ms, respectively (p < 0.001). Patients with RVESVi ≤ 38 mL/m2 and native T1 ≤ 1119 ms had significantly better outcomes than all other combinations (p < 0.001). Furthermore, patients with RVESVi > 38mL/m2 and native T1 ≤ 1119 ms had significantly better survival than patients with RVESVi > 38mL/m2 and native T1 > 1119ms (p = 0.017). CONCLUSION: We identified prognostically relevant CMR metrics and thresholds for patients with SSc-PH. Assessing myocardial tissue characterisation alongside RV function confers added value in SSc-PH and may represent an additional treatment target.

2.
BMJ Open Gastroenterol ; 11(1)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302475

RESUMO

OBJECTIVE: Coeliac disease (CD) diagnosis generally depends on histological examination of duodenal biopsies. We present the first study analysing the concordance in examination of duodenal biopsies using digitised whole-slide images (WSIs). We further investigate whether the inclusion of immunoglobulin A tissue transglutaminase (IgA tTG) and haemoglobin (Hb) data improves the interobserver agreement of diagnosis. DESIGN: We undertook a large study of the concordance in histological examination of duodenal biopsies using digitised WSIs in an entirely virtual reporting setting. Our study was organised in two phases: in phase 1, 13 pathologists independently classified 100 duodenal biopsies (40 normal; 40 CD; 20 indeterminate enteropathy) in the absence of any clinical or laboratory data. In phase 2, the same pathologists examined the (re-anonymised) WSIs with the inclusion of IgA tTG and Hb data. RESULTS: We found the mean probability of two observers agreeing in the absence of additional data to be 0.73 (±0.08) with a corresponding Cohen's kappa of 0.59 (±0.11). We further showed that the inclusion of additional data increased the concordance to 0.80 (±0.06) with a Cohen's kappa coefficient of 0.67 (±0.09). CONCLUSION: We showed that the addition of serological data significantly improves the quality of CD diagnosis. However, the limited interobserver agreement in CD diagnosis using digitised WSIs, even after the inclusion of IgA tTG and Hb data, indicates the importance of interpreting duodenal biopsy in the appropriate clinical context. It further highlights the unmet need for an objective means of reproducible duodenal biopsy diagnosis, such as the automated analysis of WSIs using artificial intelligence.


Assuntos
Doença Celíaca , Humanos , Doença Celíaca/diagnóstico , Transglutaminases , Inteligência Artificial , Variações Dependentes do Observador , Imunoglobulina A
4.
Vaccines (Basel) ; 11(12)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38140245

RESUMO

INTRODUCTION: With the containment of the COVID-19 pandemic in Côte d'Ivoire, efforts were made to seamlessly integrate COVID-19 vaccination into the national immunization program. A collaborative initiative involving UNICEF, WHO, GAVI, and partner organizations resulted in the creation of the COVID-19 Vaccine Integration Mapping Tool. This paper presents a case study documenting the field testing of the integration mapping tool and assessing the integration of COVID-19 vaccination within primary healthcare and routine immunization in Côte d'Ivoire. The study aims to describe the pilot process, gather feedback on tool usefulness and challenges, and establish integration priorities through roadmap development. METHODS: Under the guidance of the Ministry of Health and Universal Coverage Cabinet, a workshop was conducted with participants from major health programs to field test the tool. Data analysis was performed using Excel, and the results were presented through tables, heat maps, and line graphs. RESULTS: The first-of-its-kind field test of the integration mapping tool in Côte d'Ivoire showcased its potential to bring key partners together to discuss the current state of integration, improve transparency about resource allocation, and enhance data management for the incorporation of COVID-19 vaccination into existing immunization systems. The integration of COVID-19 vaccines in Côte d'Ivoire showed a moderate level of progress, with improvement needed in resource allocation, payment systems, targeting of highest-risk groups and vaccine administration. Support should be increased for target population identification, distribution points, quality of care mechanisms, and health personnel training. Health information systems and access to essential medicines were relatively satisfactory. Integration into existing programs, intersectoral collaboration, national health strategy, communication strategy, community participation, and data utilization require improvement. The post-workshop satisfaction survey gave the tool a score of 7 out of 10. Early lessons from Côte d'Ivoire provide guidance on enhancing integration, focusing on data-driven decision-making, collaboration, stakeholder engagement, and effective leadership. CONCLUSIONS: The field test of the integration mapping tool (IMT) in Côte d'Ivoire is groundbreaking as it exemplifies the transformative potential of innovative tools in immunization practices. Application of the IMT sets a precedent for seamless COVID-19 vaccination integration worldwide, emphasizing data-driven decision-making, collaboration, timing, and leadership. The success of the pilot exercise in Côte d'Ivoire was attributed to political commitment, well-facilitated workshops, assessments, and the fact that the team in the country had previously developed an initial integration plan.

5.
Clin Med (Lond) ; 23(5): 449-454, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37775164

RESUMO

Pulmonary hypertension (PH) is common, with an estimated prevalence of approximately 1% that increases with age. Prompt and accurate diagnosis is key to institute timely and appropriate therapy to improve symptoms and prognosis. The international guidelines for the diagnosis and management of PH have recently been updated, with a lowering of the haemodynamic threshold for diagnosis to a mean pulmonary artery pressure >20 mmHg. New diagnostic algorithms and revised indications for screening in at-risk groups have been developed to facilitate early referral to specialist PH centres. This includes fast-track referral pathways for patients who are either clinically high-risk or are at-risk for pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH). This review summarises key changes in the PH guidelines for general physicians who are, most often, the first healthcare professionals to encounter these patients and consequently have a key role as referrers into specialist PH services.


Assuntos
Hipertensão Pulmonar , Médicos , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/terapia , Prognóstico , Doença Crônica
6.
Eur Heart J Cardiovasc Imaging ; 24(4): 463-471, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35775814

RESUMO

AIMS: Cardiovascular involvement in systemic sclerosis (SSc) is heterogeneous and ill-defined. This study aimed to: (i) discover cardiac phenotypes in SSc by cardiovascular magnetic resonance (CMR); (ii) provide a CMR-based algorithm for phenotypic classification; and (iii) examine for associations between phenotypes and mortality. METHODS AND RESULTS: A retrospective, single-centre, observational study of 260 SSc patients who underwent clinically indicated CMR including native myocardial T1 and T2 mapping from 2016 to 2019 was performed. Agglomerative hierarchical clustering using only CMR variables revealed five clusters of SSc patients with shared CMR characteristics: dilated right hearts with right ventricular failure (RVF); biventricular failure dilatation and dysfunction (BVF); and normal function with average cavity (NF-AC), normal function with small cavity (NF-SC), and normal function with large cavity (NF-LC) sizes. Phenotypes did not co-segregate with clinical or antibody classifications. A CMR-based decision tree for phenotype classification was created. Sixty-three (24%) patients died during a median follow-up period of 3.4 years. After adjustment for age and presence of pulmonary hypertension (PH), independent CMR predictors of all-cause mortality were native T1 (P < 0.001) and right ventricular ejection fraction (RVEF) (P = 0.0032). NF-SC and NF-AC groups had more favourable prognoses (P≤0.036) than the other three groups which had no differences in prognoses between them (P > 0.14). Hazard ratios (HR) were statistically significant for RVF (HR = 8.9, P < 0.001), BVF (HR = 5.2, P = 0.006), and NF-LC (HR = 4.9, P = 0.002) groups. The NF-LC group remained significantly predictive of mortality after adjusting for RVEF, native T1, and PH diagnosis (P = 0.0046). CONCLUSION: We identified five CMR-defined cardiac SSc phenotypes that did not co-segregate with clinical data and had distinct outcomes, offering opportunities for a more precision-medicine based management approach.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Escleroderma Sistêmico , Humanos , Volume Sistólico , Estudos Retrospectivos , Imagem Cinética por Ressonância Magnética/métodos , Função Ventricular Direita , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico por imagem , Prognóstico , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/etiologia , Espectroscopia de Ressonância Magnética , Valor Preditivo dos Testes
7.
Arthritis Rheumatol ; 75(3): 449-458, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36122180

RESUMO

OBJECTIVE: Pulmonary hypertension (PH) is a serious complication of systemic sclerosis (SSc). In this study, we explored the prediction of short-term risk for PH using serial pulmonary function tests (PFTs) and other disease features. METHODS: SSc patients in whom disease onset occurred ≥10 years prior to data retrieval and for whom autoantibody specificity and PFT data were available were included in this study. Mixed-effects modeling was used to describe changes in PFTs over time. Landmarking was utilized to include serial assessments and stratified Cox proportional hazards regression analysis with landmarks as strata was used to develop the PH prediction models. RESULTS: We analyzed data from 1,247 SSc patients, 16.3% of whom were male and 35.8% of whom had diffuse cutaneous SSc. Anticentromere, antitopoisomerase, and anti-RNA polymerase antibodies were observed in 29.8%, 22.0%, and 11.4% of patients, respectively, and PH developed in 13.6% of patients. Over time, diffusing capacity for carbon monoxide (DLco) and carbon monoxide transfer coefficient (Kco) declined in all SSc patients (up to 1.5% per year) but demonstrated much greater annual decline (up to 4.5% and 4.8%, respectively) in the 5-7 years preceding PH diagnosis. Comparisons between multivariable models including either DLco, Kco, or forced vital capacity (FVC)/DLco ratio, demonstrated that both absolute values and change over the preceding year in those measurements were strongly associated with the risk of PH (hazard ratio [HR] 0.93 and 0.76 for Kco and its change; HR 0.90 and 0.96 for DLco and its change; and HR 1.08 and 2.01 for FVC/DLco ratio and its change; P < 0.001 for all). The Kco-based model had the greatest discriminating ability (Harrell's C-statistic 0.903). CONCLUSION: Our findings strongly support the importance of PFT trends over time in identifying patients at risk of developing PH.


Assuntos
Hipertensão Pulmonar , Escleroderma Sistêmico , Humanos , Masculino , Feminino , Hipertensão Pulmonar/complicações , Pulmão , Monóxido de Carbono , Capacidade Vital
8.
Hum Resour Health ; 20(1): 58, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35840965

RESUMO

BACKGROUND: This paper explores the extent of community-level stock-out of essential medicines among community health workers (CHWs) in low- and middle-income countries (LMICs) and identifies the reasons for and consequences of essential medicine stock-outs. METHODS: A systematic review was conducted and reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Five electronic databases were searched with a prespecified strategy and the grey literature examined, January 2006-March 2021. Papers containing information on (1) the percentage of CHWs stocked out or (2) reasons for stock-outs along the supply chain and consequences of stock-out were included and appraised for risk of bias. Outcomes were quantitative data on the extent of stock-out, summarized using descriptive statistics, and qualitative data regarding reasons for and consequences of stock-outs, analyzed using thematic content analysis and narrative synthesis. RESULTS: Two reviewers screened 1083 records; 78 evaluations were included. Over the last 15 years, CHWs experienced stock-outs of essential medicines nearly one third of the time and at a significantly (p < 0.01) higher rate than the health centers to which they are affiliated (28.93% [CI 95%: 28.79-29.07] vs 9.17% [CI 95%: 8.64-9.70], respectively). A comparison of the period 2006-2015 and 2016-2021 showed a significant (p < 0.01) increase in CHW stock-out level from 26.36% [CI 95%: 26.22-26.50] to 48.65% [CI 95%: 48.02-49.28] while that of health centers increased from 7.79% [95% CI 7.16-8.42] to 14.28% [95% CI 11.22-17.34]. Distribution barriers were the most cited reasons for stock-outs. Ultimately, patients were the most affected: stock-outs resulted in out-of-pocket expenses to buy unavailable medicines, poor adherence to medicine regimes, dissatisfaction, and low service utilization. CONCLUSIONS: Community-level stock-out of essential medicines constitutes a serious threat to achieving universal health coverage and equitable improvement of health outcomes. This paper suggests stock-outs are getting worse, and that there are particular barriers at the last mile. There is an urgent need to address the health and non-health system constraints that prevent the essential medicines procured for LMICs by international and national stakeholders from reaching the people who need them the most.


Assuntos
Agentes Comunitários de Saúde , Medicamentos Essenciais , Atenção à Saúde , Países em Desenvolvimento , Humanos
9.
Rheumatology (Oxford) ; 61(3): 1106-1114, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34142120

RESUMO

OBJECTIVES: The current study evaluates survival rates among SSc-associated pulmonary arterial hypertension (SSc-PAH) patients on i.v. prostanoids, and short-term impact of i.v. prostanoids on clinical and haemodynamic parameters. METHODS: Baseline demographics, invasive and non-invasive data, European Society of Cardiology (ESC) score and REVEAL score of 81 SSc-PAH patients (median age 61 years, interquartile range 54-67 years, 84% females) were prospectively recorded, from November 2006 till November 2020, before initiation of i.v. prostanoids, and at first formal reassessment. Survival data were retrieved from National Health Service Spine and hospital databases. RESULTS: Significant improvements in clinical and haemodynamic parameters in response to i.v. prostanoid therapy were documented. Functional class (FC) (16.6% improved by 1FC, P =0.041), mean pulmonary arterial pressure (-6.5 mmHg, P =0.036), pulmonary vascular resistance (-2.6 WU, P =0.012), cardiac index (Q/m2) (+0.7 l/min/m2, P =0.003) and mixed venous oxygen saturation (SvO2) (+3%, P =0.036) improved. Estimated survival for CTD-PAH patients on i.v. prostanoids was 64%, 31% and 18%, at 1 year, 3 years and 5 years, respectively. Independent baseline predictors of mortality were older age (HR: 1.043, 95% CI: 1.011-1.075, P =0.007), higher N-terminal pro-brain natriuretic peptide levels (HR: 2.191, 95% CI: 1.131-4.243, P =0.020), and lower SvO2 levels (HR: 0.962, 95% CI: 0.926-0.998, P =0.039). High ESC risk or high and very high REVEAL score was associated with significantly worse survival compared with patients with lower risk scores, both at baseline and when reassessed after a median of 6.5 months. CONCLUSIONS: Survival among SSc-PAH patients on i.v. prostanoids remains poor, risk scoring at baseline and after 6.5 months of therapy improves prognostication.


Assuntos
Prostaglandinas/uso terapêutico , Hipertensão Arterial Pulmonar/tratamento farmacológico , Escleroderma Sistêmico/tratamento farmacológico , Administração Intravenosa , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hipertensão Arterial Pulmonar/mortalidade , Escleroderma Sistêmico/mortalidade , Taxa de Sobrevida
11.
Br J Anaesth ; 126(4): 774-790, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33612249

RESUMO

BACKGROUND: The risk of complications, including death, is substantially increased in patients with pulmonary hypertension (PH) undergoing anaesthesia for surgical procedures, especially in those with pulmonary arterial hypertension (PAH) and chronic thromboembolic PH (CTEPH). Sedation also poses a risk to patients with PH. Physiological changes including tachycardia, hypotension, fluid shifts, and an increase in pulmonary vascular resistance (PH crisis) can precipitate acute right ventricular decompensation and death. METHODS: A systematic literature review was performed of studies in patients with PH undergoing non-cardiac and non-obstetric surgery. The management of patients with PH requiring sedation for endoscopy was also reviewed. Using a framework of relevant clinical questions, we review the available evidence guiding operative risk, risk assessment, preoperative optimisation, and perioperative management, and identifying areas for future research. RESULTS: Reported 30 day mortality after non-cardiac and non-obstetric surgery ranges between 2% and 18% in patients with PH undergoing elective procedures, and increases to 15-50% for emergency surgery, with complications and death usually relating to acute right ventricular failure. Risk factors for mortality include procedure-specific and patient-related factors, especially markers of PH severity (e.g. pulmonary haemodynamics, poor exercise performance, and right ventricular dysfunction). Most studies highlight the importance of individualised preoperative risk assessment and optimisation and advanced perioperative planning. CONCLUSIONS: With an increasing number of patients requiring surgery in specialist and non-specialist PH centres, a systematic, evidence-based, multidisciplinary approach is required to minimise complications. Adequate risk stratification and a tailored-individualised perioperative plan is paramount.


Assuntos
Consenso , Prova Pericial/normas , Hipertensão Pulmonar/cirurgia , Assistência Perioperatória/normas , Complicações Pós-Operatórias/prevenção & controle , Prova Pericial/métodos , Humanos , Hipertensão Pulmonar/diagnóstico , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/diagnóstico
12.
Eur Respir J ; 57(2)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32631835

RESUMO

Health-related quality of life (HRQoL) scores assess symptom burden in pulmonary arterial hypertension (PAH) but data regarding their role in prognostication and risk stratification are limited. We assessed these relationships using the emPHasis-10 HRQoL measure.1745 patients with idiopathic PAH (IPAH), drug-induced PAH (DPAH), heritable PAH (HPAH) (collectively "(I/D/H)PAH"), or connective tissue disease-associated PAH (CTD-PAH), who had completed emPHasis-10 questionnaires at one of six UK referral centres between 2014 and 2017, were identified. Correlations with exercise capacity and World Health Organization (WHO) functional class were assessed, and exploratory risk stratification thresholds were tested.Moderate correlations were seen between emPHasis-10 scores and 6-min walk distance (r=-0.546), incremental shuttle walk distance (r=-0.504) and WHO functional class (r=0.497) (all p<0.0001). Distribution of emPHasis-10 score differed significantly between each WHO functional class (all p<0.0001). On multivariate analysis, emPHasis-10 score, but not WHO functional class, was an independent predictor of mortality. In a risk stratification approach, scores of 0-16, 17-33 and 34-50 identified incident patients with 1-year mortality of 5%, 10% and 23%, respectively. Survival of patients in WHO functional class III could be further stratified using an emPHasis-10 score ≥34 (p<0.01). At follow-up, patients with improved emPHasis-10 scores had improved exercise capacity (p<0.0001) and patients who transitioned between risk groups demonstrated similar survival to patients originally in those risk groups.The emPHasis-10 score is an independent prognostic marker in patients with (I/D/H)PAH or CTD-PAH. It has utility in risk stratification in addition to currently used parameters. Improvement in emPHasis-10 score is associated with improved exercise capacity.


Assuntos
Doenças do Tecido Conjuntivo , Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Doenças do Tecido Conjuntivo/complicações , Humanos , Qualidade de Vida , Reino Unido
13.
J Geriatr Phys Ther ; 43(4): E53-E57, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31373943

RESUMO

BACKGROUND/PURPOSE: The carotid bifurcation (CB) is the location of the carotid sinus and the baroreceptors and is also a major site for atherosclerotic plaque formation. Health care providers have therefore been cautioned to avoid the CB during carotid pulse palpation (CPP) to prevent triggering the baroreflex, occluding an artery, or propagating a thrombus. Potential risks of adverse events during CPP may be greater for older adults due to age-related vascular changes and increased risk of baroreceptor hypersensitivity. The exact location of the CB relative to easily identifiable landmarks has, however, not been well-studied. The purpose of this descriptive study was to identify the location of the CB relative to key landmarks in a cadaver sample and to make recommendations allowing clinicians to avoid the CB during CPP. METHODS: The CB and other regional landmarks in 17 male and 20 female cadavers were exposed by dissection and pins were placed at all landmarks. Digital calipers were then used to measure the distance between the CB and all landmarks. RESULTS AND DISCUSSION: The mean vertical distance from the laryngeal prominence (LP) to the CB was 25.14 mm for females and 36.13 mm for males. No CBs were located below the LP. Ninety-four percent of female CBs and 100% of male CBs were located above the LP, and 74% of female subjects and 87% of male subjects had CBs greater than 20.00 mm superior to the LP. No clinically relevant relationships were found between the CB and any of the other measured landmarks. CONCLUSIONS: Based on this cadaver sample, CPP below the level of the LP in a supine individual would be unlikely to compress the CB and thus unlikely to trigger the baroreflex or occlude the region of greatest atherosclerotic buildup. If a pulse is not palpable below the LP, moving vertically up to 1 cm above the LP in a supine individual would be likely to compress the CB in only a small number of cases.


Assuntos
Artérias Carótidas , Idoso , Cadáver , Artérias Carótidas/anatomia & histologia , Feminino , Humanos , Masculino , Palpação
14.
BMJ Case Rep ; 12(12)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31796457

RESUMO

Calcium pyrophosphate deposition (CPPD) disease is a crystal arthropathy primarily affecting peripheral joints, most commonly the wrist and the knees. However, CPPD in the cervical spine is a rare entity. This report describes a case of CPPD of the cervical spine which presents with symptoms of neck pain and brachalgia. A 62-year-old woman presented with left-sided upper limb and neck pain. MRI scanning revealed a low signal abnormality within the C6 and C7 vertebrae, and the possibility of lymphoma was raised. The patient was recalled for gadolinium-enhanced scans which showed perivertebral and marrow enhancement. Fine-needle aspirate histology initially suggested a spindle cell tumour or lymphoma. However, CT-guided biopsy showed positively birefringent crystals, confirming CPPD. CPPD of the spine is a rare differential of nerve impingement in the cervical spine when MRI scanning perivertebral signal enhancement. Furthermore, CPPD of the spine can mimic malignancy.


Assuntos
Vértebras Cervicais/patologia , Condrocalcinose/patologia , Doenças da Coluna Vertebral/patologia , Biópsia por Agulha Fina , Pirofosfato de Cálcio/análise , Vértebras Cervicais/diagnóstico por imagem , Condrocalcinose/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Biópsia Guiada por Imagem , Linfoma/diagnóstico , Pessoa de Meia-Idade , Cervicalgia/etiologia , Doenças da Coluna Vertebral/diagnóstico , Tomografia Computadorizada por Raios X
15.
Br J Pharmacol ; 176(9): 1251-1267, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30761523

RESUMO

BACKGROUND AND PURPOSE: Pulmonary arterial hypertension (PAH) is an incurable, incapacitating disorder resulting from increased pulmonary vascular resistance, pulmonary arterial remodelling, and right ventricular failure. In preclinical models, the combination of a PDE5 inhibitor (PDE5i) with a neprilysin inhibitor augments natriuretic peptide bioactivity, promotes cGMP signalling, and reverses the structural and haemodynamic deficits that characterize PAH. Herein, we conducted a randomized, double-blind, placebo-controlled trial to assess the efficacy and safety of repurposing the neprilysin inhibitor, racecadotril, in PAH. EXPERIMENTAL APPROACH: Twenty-one PAH patients stable on PDE5i therapy were recruited. Acute haemodynamic and biochemical changes following a single dose of racecadotril or matching placebo were determined; this was followed by a 14-day safety and efficacy evaluation. The primary endpoint in both steps was the maximum change in circulating atrial natriuretic peptide (ANP) concentration (Δmax ), with secondary outcomes including pulmonary and systemic haemodynamics plus mechanistic biomarkers. KEY RESULTS: Acute administration of racecadotril (100 mg) resulted in a 79% increase in the plasma ANP concentration and a 106% increase in plasma cGMP levels, with a concomitant 14% fall in pulmonary vascular resistance. Racecadotril (100 mg; t.i.d.) treatment for 14 days resulted in a 19% rise in plasma ANP concentration. Neither acute nor chronic administration of racecadotril resulted in a significant drop in mean arterial BP or any serious adverse effects. CONCLUSIONS AND IMPLICATIONS: This Phase IIa evaluation provides proof-of-principle evidence that neprilysin inhibitors may have therapeutic utility in PAH and warrants a larger scale prospective trial.


Assuntos
Neprilisina/uso terapêutico , Hipertensão Arterial Pulmonar/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Light Sci Appl ; 7: 99, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30534368

RESUMO

Single-molecule localization microscopy (SMLM) aims for maximized precision and a high signal-to-noise ratio1. Both features can be provided by placing the emitter in front of a metal-dielectric nanocoating that acts as a tuned mirror2-4. Here, we demonstrate that a higher photon yield at a lower background on biocompatible metal-dielectric nanocoatings substantially improves SMLM performance and increases the localization precision by up to a factor of two. The resolution improvement relies solely on easy-to-fabricate nanocoatings on standard glass coverslips and is spectrally and spatially tunable by the layer design and wavelength, as experimentally demonstrated for dual-color SMLM in cells.

17.
Opt Express ; 26(16): 21301-21313, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30119432

RESUMO

Fluorescence microscopy allows specific and selective imaging of biological samples. Unfortunately, unspecific background due to auto-fluorescence, scattering, and non-ideal labeling efficiency often adversely affect imaging. Surface plasmon-coupled emission (SPCE) is known to selectively mediate fluorescence that spatially originates from regions close to the metal interface. However, SPCE combined with fluorescence imaging has not been widely successful so far, most likely due to its limited photon yield, which makes it tedious to identify the exact window of the application. As the strength of SPCE based imaging is its unique sectioning capabilities. We decided to identify its clear beneficial operational regime for biological settings by interrogating samples in the presence of ascending background levels. For fluorescent beads as well as live-cell imaging as examples, we show how to extend the imaging performance in extremely high photon background environments. In a common setup using plasmonic gold-coated coverslips using an objective-based total internal reflection fluorescence microscope (TIRF-M), we theoretically and experimentally characterize our fluoplasmonics (f-Pics) approach by providing general user guidance in choosing f-Pics over TIRF-M or classical wide-field (WF).

18.
Heart Lung Circ ; 27(11): e101-e104, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29678310

RESUMO

Pulmonary hypertension is a serious condition with multiple underlying aetiologies which require different treatment strategies. We present a case of severe idiopathic pulmonary arterial hypertension in a 20-year-old patient with ongoing breathlessness. She was initially diagnosed with asthma and panic attacks in community care. As the symptoms became progressively worse, she was referred for pulmonary hypertension clinic assessment. Ventilation/perfusion single-photon emission computed tomography (V/Q SPECT) showed grossly abnormal perfusion defects which were mismatched to the ventilation scan, suggestive of chronic thromboembolic disease. However, corroborating computed tomographic (CT) pulmonary angiogram and invasive pulmonary angiography showed no thromboembolic disease. Histological examination of the pulmonary arteries post-mortem showed changes consistent with idiopathic pulmonary arterial hypertension. This case highlighted the clinical challenges in interpreting the investigation results and phenotyping pulmonary hypertension. V/Q SPECT might have a role in visualising the extent of vasculopathies in pulmonary arterial hypertension.


Assuntos
Hipertensão Pulmonar/diagnóstico , Artéria Pulmonar/diagnóstico por imagem , Pressão Propulsora Pulmonar/fisiologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Cateterismo Cardíaco , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Hipertensão Pulmonar/fisiopatologia , Pulmão/diagnóstico por imagem , Embolia Pulmonar , Relação Ventilação-Perfusão , Adulto Jovem
19.
J Scleroderma Relat Disord ; 3(1): NP1-NP4, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35382118

RESUMO

Purpose: To describe cardiac transplantation in a young woman with juvenile onset diffuse scleroderma and cardiac involvement. Methods: Case report. Results: A young White girl developed anti-topoisomerase-1 positive diffuse scleroderma aged 14 years with myositis. Pulmonary function tests were normal. Skin disease was treated with mycophenolate mofetil 1 g twice daily, methotrexate 7.5 mg weekly and periodic intravenous prostacyclin. When aged 17 years, she developed raised troponin T of 0.207 mcg/L (normal range <0.03) and NTproBNP (155 pmol/L); 6-min walking distance was 341 m, and she had episodes of presyncope with effort. The next year she developed symptomatic ventricular tachycardias and dual-chamber implantable cardioverter-defibrillator was inserted, with further episodes of ventricular tachycardia and one shock delivered. By age 19 years, 6-min walking distance was 125 m. Echocardiography showed ejection fraction of 15%-20% with dilated left ventricle and pericardial effusion. She was treated with intravenous Rituximab. She became breathless while dressing and managed only 118 m in 6 min. She experienced increasing orthopnoea and peripheral oedema and was found to be in a low cardiac output state, requiring treatment with intravenous milrinone to maintain renal function. She underwent orthotopic cardiac transplantation, making an excellent post-operative recovery, and was discharged 16 days later with tacrolimus, mycophenolate mofetil and prednisolone. After 1 year, she was in New York Heart Association functional class I and with normal cardiac function on echocardiography. Conclusion: This case illustrates the severe cardiac involvement that can occur in juvenile onset diffuse cutaneous systemic sclerosis, in which cardiac involvement is the leading cause of death.

20.
RSC Adv ; 8(40): 22569-22576, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35539709

RESUMO

Efficient substrates for surface-enhanced Raman spectroscopy (SERS) are under constant development, since time-consuming and costly fabrication routines are often an issue for high-throughput spectroscopy applications. In this research, we use a two-step fabrication method to produce self-organized parallel-oriented plasmonic gold nanostructures. The fabrication routine is ready for wafer-scale production involving only low-energy ion beam irradiation and metal deposition. The optical spectroscopy features of the resulting structures show a successful bidirectional plasmonic response. The localized surface plasmon resonances (LSPRs) of each direction are independent from each other and can be tuned by the fabrication parameters. This ability to tune the LSPR characteristics allows the development of optimized plasmonic nanostructures to match different laser excitations and optical transitions for any arbitrary analyte. Moreover, in this study, we probe the polarization and wavelength dependence of such bidirectional plasmonic nanostructures by a complementary spectroscopic ellipsometry and Raman spectroscopy analysis. We observe a significant signal amplification by the SERS substrates and determine enhancement factors of over a thousand times. We also perform finite element method-based calculations of the electromagnetic enhancement for the SERS signal provided by the plasmonic nanostructures. The calculations are based on realistic models constructed using the same particle sizes and shapes experimentally determined by scanning electron microscopy. The spatial distribution of electric field enhancement shows some dispersion in the LSPR, which is a direct consequence of the semi-random distribution of hotspots. The signal enhancement is highly efficient, making our SERS substrates attractive candidates for high-throughput chemical sensing applications in which directionality, chemical stability, and large-scale fabrication are essential requirements.

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