Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
Lancet Infect Dis ; 23(9): 1085-1094, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37230105

RESUMO

BACKGROUND: In previous trials, point-of-care testing of C-reactive protein (CRP) concentrations safely reduced antibiotic use in non-severe acute respiratory infections in primary care. However, these trials were done in a research-oriented context with close support from research staff, which could have influenced prescribing practices. To better inform the potential for scaling up point-of-care testing of CRP in respiratory infections, we aimed to do a pragmatic trial of the intervention in a routine care setting. METHODS: We did a pragmatic, cluster-randomised controlled trial at 48 commune health centres in Viet Nam between June 1, 2020, and May 12, 2021. Eligible centres served populations of more than 3000 people, handled 10-40 respiratory infections per week, had licensed prescribers on site, and maintained electronic patient databases. Centres were randomly allocated (1:1) to provide point-of-care CRP testing plus routine care or routine care only. Randomisation was stratified by district and by baseline prescription level (ie, the proportion of patients with suspected acute respiratory infections to whom antibiotics were prescribed in 2019). Eligible patients were aged 1-65 years and visiting the commune health centre for a suspected acute respiratory infection with at least one focal sign or symptom and symptoms lasting less than 7 days. The primary endpoint was the proportion of patients prescribed an antibiotic at first attendance in the intention-to-treat population. The per-protocol analysis included only people who underwent CRP testing. Secondary safety outcomes included time to resolution of symptoms and frequency of hospitalisation. This trial is registered with ClinicalTrials.gov, NCT03855215. FINDINGS: 48 commune health centres were enrolled and randomly assigned, 24 to the intervention group (n=18 621 patients) and 24 to the control group (n=21 235). 17 345 (93·1%) patients in the intervention group were prescribed antibiotics, compared with 20 860 (98·2%) in the control group (adjusted relative risk 0·83 [95% CI 0·66-0·93]). Only 2606 (14%) of 18 621 patients in the intervention group underwent CRP testing and were included in the per-protocol analysis. When analyses were restricted to this population, larger reductions in prescribing were noted in the intervention group compared with the control group (adjusted relative risk 0·64 [95% CI 0·60-0·70]). Time to resolution of symptoms (hazard ratio 0·70 [95% CI 0·39-1·27]) and frequency of hospitalisation (nine in the intervention group vs 17 in the control group; adjusted relative risk 0·52 [95% CI 0·23-1·17]) did not differ between groups. INTERPRETATION: Use of point-of-care CRP testing efficaciously reduced prescription of antibiotics in patients with non-severe acute respiratory infections in primary health care in Viet Nam without compromising patient recovery. The low uptake of CRP testing suggests that barriers to implementation and compliance need to be addressed before scale-up of the intervention. FUNDING: Australian Government, UK Government, and the Foundation for Innovative New Diagnostics.


Assuntos
Antibacterianos , Proteína C-Reativa , Testes Imediatos , Infecções Respiratórias , Humanos , Antibacterianos/uso terapêutico , Austrália , Proteína C-Reativa/análise , Atenção Primária à Saúde , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , População do Sudeste Asiático , Vietnã/epidemiologia , Análise por Conglomerados
3.
Expert Rev Clin Pharmacol ; 15(9): 1017-1025, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36093865

RESUMO

INTRODUCTION: Takotsubo syndrome (TTS) is an acute inflammatory disorder involving first the vasculature and then the myocardium. It occurs relatively frequently, especially in aging women after acute physical and emotional stress. There is also increasing recognition that TTS attacks are sometimes precipitated by pharmacotherapy. AREAS COVERED: The pathogenesis of TTS is described, including components of a complex biochemical 'cascade' centering on aberrant post-receptor signaling following ß2-adrenoceptors stimulation and resultant nitric oxide (NO) release and development of nitrosative stress. Examples and significance of drug-induced TTS are also described. Currently available therapeutic information regarding TTS is presented, both for management of patients acutely and in the long-term. Furthermore, development of specific therapies to block components of the pathogenetic TTS 'cascade' is discussed. EXPERT OPINION: The biochemical 'cascade' in TTS revolves around an aberrant post-receptor response to ß2-adrenoceptor stimulation, increased responsiveness to NO and triggering of activation of poly(ADP-ribose) polymerase (PARP). In theory, interruption of this 'cascade' represents a logical approach to improving both symptomatic status and survival post TTS. Currently, there is some evidence supporting routine long-term treatment post TTS with either ACE inhibitors or angiotensin receptor antagonists, both to reduce risk of recurrence and to improve survival. Results of ongoing controlled clinical trials are awaited.


Assuntos
Cardiomiopatia de Takotsubo , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Feminino , Humanos , Óxido Nítrico , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases , Receptores Adrenérgicos , Fatores de Risco , Cardiomiopatia de Takotsubo/induzido quimicamente , Cardiomiopatia de Takotsubo/tratamento farmacológico
4.
Int J Antimicrob Agents ; 60(4): 106659, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35988665

RESUMO

INTRODUCTION: Bloodstream infections (BSIs) are a leading cause of sepsis, which is a life-threatening condition that significantly contributes to the mortality of bacterial infections. Aminoglycoside antibiotics such as gentamicin or amikacin are essential medicines in the treatment of BSIs, but their clinical efficacy is increasingly being compromised by antimicrobial resistance. The aminoglycoside apramycin has demonstrated preclinical efficacy against aminoglycoside-resistant and multidrug-resistant (MDR) Gram-negative bacilli (GNB) and is currently in clinical development for the treatment of critical systemic infections. METHODS: This study collected a panel of 470 MDR GNB isolates from healthcare facilities in Cambodia, Laos, Singapore, Thailand and Vietnam for a multicentre assessment of their antimicrobial susceptibility to apramycin in comparison with other aminoglycosides and colistin by broth microdilution assays. RESULTS: Apramycin and amikacin MICs ≤ 16 µg/mL were found for 462 (98.3%) and 408 (86.8%) GNB isolates, respectively. Susceptibility to gentamicin and tobramycin (MIC ≤ 4 µg/mL) was significantly lower at 122 (26.0%) and 101 (21.5%) susceptible isolates, respectively. Of note, all carbapenem and third-generation cephalosporin-resistant Enterobacterales, all Acinetobacter baumannii and all Pseudomonas aeruginosa isolates tested in this study appeared to be susceptible to apramycin. Of the 65 colistin-resistant isolates tested, four (6.2%) had an apramycin MIC > 16 µg/mL. CONCLUSION: Apramycin demonstrated best-in-class activity against a panel of GNB isolates with resistances to other aminoglycosides, carbapenems, third-generation cephalosporins and colistin, warranting continued consideration of apramycin as a drug candidate for the treatment of MDR BSIs.


Assuntos
Amicacina , Colistina , Aminoglicosídeos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Sudeste Asiático , Hemocultura , Carbapenêmicos , Cefalosporinas , Colistina/farmacologia , Farmacorresistência Bacteriana Múltipla , Gentamicinas , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana , Nebramicina/análogos & derivados , Pseudomonas aeruginosa , Tobramicina
5.
Am J Trop Med Hyg ; 107(1): 65-71, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35895375

RESUMO

Plasmid-Mediated Colistin Resistance 1 (mcr-1) was first reported in 2015 and is a great concern to human health. In this study, we investigated the prevalence of mcr-1 and mcr-1-positive Escherichia coli (MCRPEC) and the association in infection status among various reservoirs connected to livestock. The study was conducted in 70 poultry and swine farms in a commune in Ha Nam province, northern Vietnam. Samples were collected from farmers, food animals, domestic animals, and farm environments (flies and wastewater) for polymerase chain reaction (PCR) screening for mcr-1 gene and species identification of PCR positive isolates. Among 379 obtained mcr-1 positives isolates, Escherichia coli was the major identified, varying from 50% (2/4) in dog feces to 100% (31/31) in humans feces isolates. The prevalence of MCRPEC was 14.4% (20/139), 49.7% (96/193), 31.3% (25/80), 36.7% (40/109), 26.9% (18/67), and 3.9% (2/51) in humans, chickens, pigs, flies, wastewater, and dogs, respectively. The study identified association between MCRPEC infection status in humans and flies (OR = 3.4), between flies and chickens (OR = 5.3), and between flies and pigs (OR = 9.0). Farmers' age and farm livestock unit were also associated factors of MCRPEC infection status in humans (OR = 5.1 and 1.05, respectively). These findings bring new knowledge on antibiotic resistance in livestock setting and important suggestions on potential role of flies in the transmission of mcr-1 resistance gene.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Antibacterianos/farmacologia , Galinhas , Colistina/farmacologia , Cães , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Fazendas , Humanos , Gado , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Suínos , Vietnã/epidemiologia , Águas Residuárias
6.
Expert Rev Cardiovasc Ther ; 19(10): 917-927, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34633245

RESUMO

INTRODUCTION: Since Prinzmetal first described a 'variant' form of angina pectoris, with predominantly resting episodes of pain and cyclic severity variations, it has gradually become apparent that this clinical presentation is caused by episodes of coronary artery spasm (CAS) involving focal or diffuse changes in large and/or small coronary arteries in the presence or absence of 'fixed' coronary artery stenoses. However, most clinicians have only limited understanding of this group of disorders. AREAS COVERED: We examine the clinical presentation of CAS, associated pathologies outside the coronary vasculature, impediments to making the diagnosis, provocative diagnostic tests, available and emerging treatments, and the current understanding of pathogenesis. EXPERT OPINION: CAS is often debilitating and substantially under-diagnosed and occur mainly in women. Many patients presenting with CAS crises have non-diagnostic ECGs and normal serum troponin concentrations, but CAS can be suspected on the basis of history and association with migraine, Raynaud's phenomenon and Kounis syndrome. Definitive diagnosis requires provocative testing at coronary angiography. Treatment still centers around the use of calcium antagonists, but with greater understanding of pathogenesis, new management options are emerging.


Assuntos
Angina Pectoris Variante , Vasoespasmo Coronário , Angina Pectoris/diagnóstico , Angina Pectoris/etiologia , Angina Pectoris Variante/diagnóstico , Angina Pectoris Variante/terapia , Angiografia Coronária , Vasoespasmo Coronário/diagnóstico , Vasoespasmo Coronário/terapia , Vasos Coronários , Feminino , Humanos , Espasmo
7.
PLoS One ; 16(9): e0255470, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34499670

RESUMO

TBR225 is one of the most popular commercial rice varieties in Northern Vietnam. However, this variety is highly susceptible to bacterial leaf blight (BLB), a disease caused by Xanthomonas oryzae pv. oryzae (Xoo) which can lead to important yield losses. OsSWEET14 belongs to the SWEET gene family that encodes sugar transporters. Together with other Clade III members, it behaves as a susceptibility (S) gene whose induction by Asian Xoo Transcription-Activator-Like Effectors (TALEs) is absolutely necessary for disease. In this study, we sought to introduce BLB resistance in the TBR225 elite variety. First, two Vietnamese Xoo strains were shown to up-regulate OsSWEET14 upon TBR225 infection. To investigate if this induction is connected with disease susceptibility, nine TBR225 mutant lines with mutations in the AvrXa7, PthXo3 or TalF TALEs DNA target sequences of the OsSWEET14 promoter were obtained using the CRISPR/Cas9 editing system. Genotyping analysis of T0 and T1 individuals showed that mutations were stably inherited. None of the examined agronomic traits of three transgene-free T2 edited lines were significantly different from those of wild-type TBR225. Importantly, one of these T2 lines, harboring the largest homozygous 6-bp deletion, displayed decreased OsSWEET14 expression as well as a significantly reduced susceptibility to a Vietnamese Xoo strains and complete resistance to another one. Our findings indicate that CRISPR/Cas9 editing conferred an improved BLB resistance to a Vietnamese commercial elite rice variety.


Assuntos
Resistência à Doença/imunologia , Regulação da Expressão Gênica de Plantas , Oryza/imunologia , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Xanthomonas/fisiologia , Sistemas CRISPR-Cas , Resistência à Doença/genética , Suscetibilidade a Doenças , Proteínas de Transporte de Monossacarídeos/antagonistas & inibidores , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Mutação , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/genética
9.
ESC Heart Fail ; 8(3): 2009-2015, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33760362

RESUMO

AIMS: Takotsubo syndrome (TTS) is a form of acute myocardial inflammation, often triggered by catecholamine release surges, which accounts for approximately 10% of 'myocardial infarctions' in female patients above the age of 50. Its associated substantial risk of in-hospital mortality is mainly driven by the development of hypotension and shock. While hypotension is induced largely by factors other than low cardiac output, its precise cause is unknown, and clinical parameters associated with hypotension have not been identified previously. We therefore sought to identify the incidence and clinical/laboratory correlates of early hypotension in TTS. METHODS AND RESULTS: We analysed the in-hospital data of patients recruited to the South Australian TTS Registry. Associations between the development of hypotension, patient demographics, severity of the acute TTS attack, and key biochemical markers were sought. One hundred thirteen out of 319 patients (35%) were hypotensive (median systolic blood pressure 80 mmHg) during their index hospitalization. Development of hypotension preceded all in-hospital deaths (n = 8). On univariate analyses, patients who developed hypotension had lower left ventricular ejection fraction (P = 0.009), and higher plasma N-terminal pro brain natriuretic peptide and troponin-T concentrations (P = 0.046 and 0.008, respectively), all markers of severity of the TTS attack; hypotension also occurred less commonly in male than in female patients (P = 0.014). On multivariate linear regression analysis, female sex and lower left ventricular ejection fraction were independent correlates of the development of hypotension (P = 0.009 and 0.010, respectively). CONCLUSIONS: Early development of hypotension is very common in TTS, and its presence is associated with a substantial risk of in-hospital mortality. Hypotension is a marker of severe TTS attacks and occurs more commonly in female TTS patients.


Assuntos
Hipotensão , Cardiomiopatia de Takotsubo , Austrália , Feminino , Humanos , Hipotensão/epidemiologia , Hipotensão/etiologia , Incidência , Laboratórios , Masculino , Volume Sistólico , Cardiomiopatia de Takotsubo/diagnóstico , Cardiomiopatia de Takotsubo/epidemiologia , Função Ventricular Esquerda
10.
J Clin Apher ; 36(1): 101-108, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33037852

RESUMO

Thrombocytosis is usually seen in myeloproliferative neoplasms (MPNs) and associated with thrombohemorrhagic complications. Therapeutic thrombocytapheresis using an automatic cell separator can help to achieve prompt platelet count reduction to decrease the rate of thrombotic events. In this study, we report a single center's experience in managing MPN patients with thrombocytapheresis prior to chemotherapy. Thrombocytapheresis procedures were performed in 185 MPN patients with thrombocytosis between January 2016 and June 2017. The median percentage reduction of platelets was 44.5% and the median percentage removal efficiency was 65.2% for 83 procedures where the waste bag was sampled. Procedures were generally well tolerated with few patients having mild adverse events (13 out of 185 patients).


Assuntos
Transtornos Mieloproliferativos/terapia , Plaquetoferese/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Estudos Prospectivos , Adulto Jovem
11.
Heart Lung Circ ; 30(1): 36-44, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33168470

RESUMO

It is now 30 years since Japanese investigators first described Takotsubo Syndrome (TTS) as a disorder occurring mainly in ageing women, ascribing it to the impact of multivessel coronary artery spasm. During the intervening period, it has become clear that TTS involves relatively transient vascular injury, followed by prolonged myocardial inflammatory and eventually fibrotic changes. Hence symptomatic recovery is generally slow, currently an under-recognised issue. It appears that TTS is induced by aberrant post-ß2-adrenoceptor signalling in the setting of "surge" release of catecholamines. Resultant activation of nitric oxide synthases and increased inflammatory vascular permeation lead to prolonged myocardial infiltration with macrophages and associated oedema formation. Initially, the diagnosis of TTS was made via exclusion of relevant coronary artery stenoses, plus the presence of regional left ventricular hypokinesis. However, detection of extensive myocardial oedema on cardiac MRI imaging offers a specific basis for diagnosis. No adequate methods are yet available for definitive diagnosis of TTS at hospital presentation. Other major challenges remaining in this area include understanding of the recently demonstrated association between TTS and antecedent cancer, the development of effective treatments to reduce risk of short-term (generally due to shock) and long-term mortality, and also to accelerate symptomatic recovery.


Assuntos
Ventrículos do Coração/fisiopatologia , Imagem Cinética por Ressonância Magnética/métodos , Cardiomiopatia de Takotsubo/fisiopatologia , Função Ventricular Esquerda/fisiologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Cardiomiopatia de Takotsubo/diagnóstico
12.
BMJ Open ; 10(12): e040977, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33361164

RESUMO

INTRODUCTION: C-reactive protein (CRP), a biomarker of infection, has been used widely in high-income settings to guide antibiotic treatment in patients presenting with respiratory illnesses in primary care. Recent trials in low- and middle-income countries showed that CRP testing could safely reduce antibiotic use in patients with non-severe acute respiratory infections (ARIs) and fever in primary care. The studies, however, were conducted in a research-oriented context, with research staff closely monitoring healthcare behaviour thus potentially influencing healthcare workers' prescribing practices. For policy-makers to consider wide-scale roll-out, a pragmatic implementation study of the impact of CRP point of care (POC) testing in routine care is needed. METHODS AND ANALYSIS: A pragmatic, cluster-randomised controlled trial, with two study arms, consisting of 24 commune health centres (CHC) in the intervention arm (provision of CRP tests with additional healthcare worker guidance) and 24 facilities acting as controls (routine care). Comparison between the treatment arms will be through logistic regression, with the treatment assignment as a fixed effect, and the CHC as a random effect. With 48 clusters, an average of 10 consultations per facility per week will result in approximately 520 over 1 year, and 24 960 in total (12 480 per arm). We will be able to detect a reduction of 12% to 23% or more in immediate antibiotic prescription as a result of the CRP POC intervention. The primary endpoint is the proportion of patient consultations for ARI resulting in immediate antibiotic prescription. Secondary endpoints include the proportion of all patients receiving an antibiotic prescription regardless of ARI diagnosis, frequency of re-consultation, subsequent antibiotic use when antibiotics are not prescribed, referral and hospitalisation. ETHICS AND DISSEMINATION: The study protocol was approved by the Oxford University Tropical Research Ethics Committee (OxTREC, Reference: 53-18), and the ethical committee of the National Hospital for Tropical Diseases in Vietnam (Reference:07/HDDD-NDTW/2019). Results from this study will be disseminated via meetings with stakeholders, conferences and publications in peer-reviewed journals. Authorship and reporting of this work will follow international guidelines. TRIAL REGISTRATION DETAILS: NCT03855215; Pre-results.


Assuntos
Infecções Respiratórias , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Povo Asiático , Proteína C-Reativa/análise , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Pessoa de Meia-Idade , Testes Imediatos , Gravidez , Atenção Primária à Saúde , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Vietnã , Adulto Jovem
13.
Sci Rep ; 10(1): 20537, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239695

RESUMO

Cardiac magnetic resonance (CMR) imaging has become an important technique for non-invasive diagnosis of takotsubo syndrome (TTS). The long-term prognostic value of CMR imaging in TTS has not been fully elucidated yet. This study sought to evaluate the prognostic value of texture analysis (TA) based on CMR images in patients with TTS using machine learning. In this multicenter study (InterTAK Registry), we investigated CMR imaging data of 58 patients (56 women, mean age 68 ± 12 years) with TTS. CMR imaging was performed in the acute to subacute phase (median time after symptom onset 4 days) of TTS. TA of the left ventricle was performed using free-hand regions-of-interest in short axis late gadolinium-enhanced and on T2-weighted (T2w) images. A total of 608 TA features adding the parameters age, gender, and body mass index were included. Dimension reduction was performed removing TA features with poor intra-class correlation coefficients (ICC ≤ 0.6) and those being redundant (correlation matrix with Pearson correlation coefficient r > 0.8). Five common machine-learning classifiers (artificial neural network Multilayer Perceptron, decision tree J48, NaïveBayes, RandomForest, and Sequential Minimal Optimization) with tenfold cross-validation were applied to assess 5-year outcome including major adverse cardiac and cerebrovascular events (MACCE). Dimension reduction yielded 10 TA features carrying prognostic information, which were all based on T2w images. The NaïveBayes machine learning classifier showed overall best performance with a sensitivity of 82.9% (confidence interval (CI) 80-86.2), specificity of 83.7% (CI 75.7-92), and an area-under-the receiver operating characteristics curve of 0.88 (CI 0.83-0.92). This proof-of-principle study is the first to identify unique T2w-derived TA features that predict long-term outcome in patients with TTS. These features might serve as imaging prognostic biomarkers in TTS patients.


Assuntos
Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Cardiomiopatia de Takotsubo/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Prognóstico , Curva ROC , Medição de Risco
14.
Circulation ; 142(11): 1092-1105, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32697107

RESUMO

BACKGROUND: Aortic valve stenosis is an increasingly prevalent degenerative and inflammatory disease. Transcatheter aortic valve implantation (TAVI) has revolutionized its treatment, thereby avoiding its life-threatening/disabling consequences. Whether aortic valve stenosis is accelerated by inflammation and whether it is itself a cause of inflammation are unclear. We hypothesized that the large shear forces exerted on circulating cells, particularly on the largest circulating cells, monocytes, while passing through stenotic aortic valves result in proinflammatory effects that are resolved with TAVI. METHODS: TAVI provides a unique opportunity to compare the activation status of monocytes under high shear stress (before TAVI) and under low shear stress (after TAVI). The activation status of monocytes was determined with a single-chain antibody, MAN-1, which is specific for the activated ß2-integrin Mac-1. Monocyte function was further characterized by the adhesion of myocytes to stimulated endothelial cells, phagocytic activity, uptake of oxidized low-density lipoprotein, and cytokine expression. In addition, we designed a microfluidic system to recapitulate the shear rate conditions before and after TAVI. We used this tool in combination with functional assays, Ca2+ imaging, siRNA gene silencing, and pharmacological agonists and antagonists to identify the key mechanoreceptor mediating the shear stress sensitivity of monocytes. Last, we stained for monocytes in explanted stenotic aortic human valves. RESULTS: The resolution of high shear stress through TAVI reduces Mac-1 activation, cellular adhesion, phagocytosis, oxidized low-density lipoprotein uptake, and expression of inflammatory markers in monocytes and plasma. Using microfluidics and pharmacological and genetic studies, we could recapitulate high shear stress effects on isolated human monocytes under highly controlled conditions, showing that shear stress-dependent calcium influx and monocyte adhesion are mediated by the mechanosensitive ion channel Piezo-1. We also demonstrate that the expression of this receptor is shear stress dependent and downregulated in patients receiving TAVI. Last, we show monocyte accumulation at the aortic side of leaflets of explanted aortic valves. CONCLUSIONS: We demonstrate that high shear stress, as present in patients with aortic valve stenosis, activates multiple monocyte functions, and we identify Piezo-1 as the mainly responsible mechanoreceptor, representing a potentially druggable target. We demonstrate an anti-inflammatory effect and therefore a novel therapeutic benefit of TAVI.


Assuntos
Anti-Inflamatórios/administração & dosagem , Estenose da Valva Aórtica , Canais Iônicos/sangue , Monócitos/metabolismo , Resistência ao Cisalhamento , Estresse Mecânico , Substituição da Valva Aórtica Transcateter , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/sangue , Estenose da Valva Aórtica/cirurgia , Feminino , Humanos , Masculino
16.
Cardiovasc Drugs Ther ; 34(1): 95-100, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32076930

RESUMO

BACKGROUND: Although Takotsubo syndrome (TS) was once considered to be rare and largely benign, it is now recognized to represent a major cause of cardiac morbidity and mortality, especially in ageing women. The biochemical precipitant of attacks of TS is an increase in catecholamine concentrations within the myocardium, engendering inflammatory activation via biased post-receptor signalling at myocardial ß2-adrenoceptor level. Cases of TS have been reported in patients treated with catecholamines, and with antidepressants which limit catecholamine re-uptake. In the current investigation, we sought to delineate the extent and potential impact of this "iatrogenic" form of TS. METHODS/RESULTS: Patients' data from a regional registry of 301 consecutive cases of TS were evaluated after exclusion of patients (n = 20) in whom TS had occurred in association with life threatening extracardiac disease states. A total of 55 (18%) of patients were identified as having antecedent exposure to potentially "iatrogenic" agents (tricyclic antidepressants in 24 cases, ß2-adrenoceptor agonists in 15). Demographics, including proportion of male patients, did not differ significantly between patients with and without "iatrogenic" TS, but plasma concentrations of the catecholamine metabolite normetanephrine tended to be greater (median 1149 pmol/L vs 938 pmol/L; p = 0.03). Long-term survival (median follow-up 3 years) was marginally (p = 0.13) worse for patients with "iatrogenic" TS. CONCLUSION: Potentially iatrogenic precipitation of TS attacks (via iatrogenic elevation of catecholamine levels and ß2-adrenoceptor stimulation) is common, associated with greater elevation of plasma normetanephrine concentrations, and also with a trend towards increased long-term mortality when compared to the remainder of TS patients.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/efeitos adversos , Antidepressivos Tricíclicos/efeitos adversos , Doença Iatrogênica , Miocárdio/metabolismo , Normetanefrina/sangue , Cardiomiopatia de Takotsubo/induzido quimicamente , Função Ventricular Esquerda/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Cardiomiopatia de Takotsubo/sangue , Cardiomiopatia de Takotsubo/mortalidade , Cardiomiopatia de Takotsubo/fisiopatologia , Fatores de Tempo
17.
Contemp Clin Trials ; 90: 105894, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31740426

RESUMO

BACKGROUND: Takotsubo Syndrome(TTS), contrary to historical reports, is now increasingly recognised to be associated with substantial mortality and morbidity, both in the short- and long-term. Although TTS is often precipitated by a catecholamine "pulse", in-hospital hypotension is a common occurrence, increasing the risk of mortality. Furthermore, despite the transient catecholamine stimulus, there is increasing evidence that there are significant long term sequelae, including persistently impaired left ventricular(LV) systolic dysfunction, myocardial oedema with fibrosis, as well as persistent impairment of quality of life. A definitive therapeutic option to limit the extent of initial myocardial injury, and to accelerate recovery in TTS is therefore justified. However to date, there has been a lack of prospective studies in this area. DESIGN AND RATIONALE: NACRAM is a multi-centre, randomised, placebo-controlled trial, sequentially testing early use of intravenous N-acetylcysteine(NAC), followed by/or oral ramipril for 12 weeks. The rationale for utilising these agents is related to their effects on limiting nitrosative stress and expression of the inflammasome activator thioredoxin interacting protein(TXNIP); both processes fundamental to the pathogenesis of TTS. END POINTS: NACRAM is assessing resolution of myocardial oedema on cardiac magnetic resonance imaging(CMR), improvements in LV systolic function as measured by global longitudinal strain(GLS) on echocardiography, quality of life, and inflammatory markers. DISCUSSION: To the best of our knowledge, NACRAM will be the first prospective study to help definitively evaluate a therapeutic option in acute attacks of TTS.


Assuntos
Acetilcisteína/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Sequestradores de Radicais Livres/uso terapêutico , Ramipril/uso terapêutico , Cardiomiopatia de Takotsubo/tratamento farmacológico , Acetilcisteína/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Proteínas de Transporte/efeitos dos fármacos , Método Duplo-Cego , Sequestradores de Radicais Livres/administração & dosagem , Humanos , Inflamassomos/efeitos dos fármacos , Estudos Prospectivos , Qualidade de Vida , Ramipril/administração & dosagem , Cardiomiopatia de Takotsubo/fisiopatologia
18.
Wellcome Open Res ; 4: 102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31723673

RESUMO

Public or community engagement (PE/CE) is an increasingly important component of biomedical research. However, PE/CE projects have been criticized for focusing on the 'convenient sample' populations that are more accessible and more likely to respond, thus missing out the less-socially visible groups. In January 2018, engagement practitioners from across Southeast Asia, attending a regional workshop, undertook a discussion about the 'hard-to-reach' populations in the region, and how PE projects can better engage them.  This paper is a summary of that discussion. After an initial brainstorming exercise the hard-to-reach populations identified by workshop participants were broadly categorised into three groups: urban poor, ethnic minority groups and children in rural primary schools. Delegates identified common characteristics of the populations and possible interventions to reach them. Notes of the discussions were used as data for the report. Four common issues that become barriers for engagement were identified: (1) financial instability; (2) mobility in residency and work; (3) discrimination and isolation; and (4) limitations in local resources. It is important to recognise that a group might be more disadvantaged by one factor than the others, but often these issues inter-relate to restrict outreach. In order to engage these populations, a tailor-made programme, that suits the local context, should be created. This can be done through four strategies that have the acronym 'FIND': (1) Formative research to improve understanding of the population; (2) Integrating into local life; (3) Networking with relevant stakeholders; and (4) Developing local resources.  Our discussion highlights the importance of a deep understanding of the local contexts in order to implement relevant and acceptable engagement projects. Findings from this report may be useful for planning public engagement projects in similar settings.

19.
Protein Expr Purif ; 130: 73-80, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27713060

RESUMO

INTRODUCTION: Glycodelin is a glycoprotein with different oligosaccharides that are responsible for its diverse biological functions in contraception and immunosuppression. Therefore, it is necessary to have access to adequate amounts of glycodelin with retained carbohydrate structure for functional studies because the carbohydrate part can be lacking or be insufficient in recombinant glycodelin from prokaryotic and eukaryotic cell systems. METHODS AND RESULTS: Native glycodelin was purified from amniotic fluid by a series of affinity chromatography steps and had many glycosylated forms verified by mass spectrometry. About 7.5 mg glycodelin was obtained from 1.5 L amniotic fluid. No high molecular mass forms of glycodelin were found in amniotic fluid. Aliquots of the purified glycodelin were used as an immunogen in rabbits for antibody production against glycodelin and a calibrator in a highly sensitive glycodelin enzyme-linked immunosorbent assay (ELISA) with a detection limit of about 1 µg/L. CONCLUSIONS: Native glycodelin was purified from amniotic fluid and used as an immunogen for raising a rabbit antibody against glycodelin and a calibrator in a highly sensitive glycodelin ELISA. We found no high molecular mass forms of glycodelin in amniotic fluid. Aliquots of the purified glycodelin were set aside for functional studies which are in progress.


Assuntos
Líquido Amniótico/química , Anticorpos/química , Cromatografia de Afinidade/métodos , Glicodelina , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Glicodelina/análise , Glicodelina/química , Glicodelina/isolamento & purificação , Humanos , Coelhos
20.
BMC Infect Dis ; 16: 120, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-26968374

RESUMO

BACKGROUND: The burden of dengue continues to increase globally, with an estimated 100 million clinically apparent infections occurring each year. Although most dengue infections are asymptomatic, patients can present with a wide spectrum of clinical symptoms ranging from mild febrile illness through to severe manifestations of bleeding, organ impairment, and hypovolaemic shock due to a systemic vascular leak syndrome. Clinical diagnosis of dengue and identification of which patients are likely to develop severe disease remain challenging. This study aims to improve diagnosis and clinical management through approaches designed a) to differentiate between dengue and other common febrile illness within 72 h of fever onset, and b) among patients with dengue to identify markers that are predictive of the likelihood of evolving to a more severe disease course. METHOD/DESIGN: This is a prospective multi-centre observational study aiming to enrol 7-8000 participants aged ≥ 5 years presenting with a febrile illness consistent with dengue to outpatient health facilities in 8 countries across Asia and Latin America. Patients presenting within 72 h of fever onset who do not exhibit signs of severe disease are eligible for the study. A broad range of clinical and laboratory parameters are assessed daily for up to 6 days during the acute illness, and also at a follow up visit 1 week later. DISCUSSION: Data from this large cohort of patients, enrolled early with undifferentiated fever, will be used to develop a practical diagnostic algorithm and a robust clinical case definition for dengue. Additionally, among patients with confirmed dengue we aim to identify simple clinical and laboratory parameters associated with progression to a more severe disease course. We will also investigate early virological and serological correlates of severe disease, and examine genetic associations in this large heterogeneous cohort. In addition the results will be used to assess the new World Health Organization classification scheme for dengue in practice, and to update the guidelines for "Integrated Management of Childhood Illness" used in dengue-endemic countries. TRIAL REGISTRATION: NCT01550016. Registration Date: March 7, 2012.


Assuntos
Dengue/epidemiologia , Adolescente , Adulto , Ásia/epidemiologia , Criança , Dengue/diagnóstico , Dengue/tratamento farmacológico , Vírus da Dengue/isolamento & purificação , Diagnóstico Diferencial , Gerenciamento Clínico , Feminino , Humanos , América Latina/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA