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1.
Lancet Child Adolesc Health ; 7(1): 26-36, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36442482

RESUMO

BACKGROUND: Optimal target blood pressure to reduce adverse cardiac remodelling in children with chronic kidney disease is uncertain. We hypothesised that lower blood pressure would reduce adverse cardiac remodelling. METHODS: HOT-KID, a parallel-group, open-label, multicentre, randomised, controlled trial, was done in 14 clinical centres across England and Scotland. We included children aged 2-15 years with stage 1-4 chronic kidney disease-ie, an estimated glomerular filtration rate (eGFR) higher than 15 mL/min per 1·73 m2-and who could be followed up for 2 years. Children on antihypertensive medication were eligible as long as it could be changed to angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) if they were not already receiving these therapies. Participants were randomly assigned (1:1) to standard treatment (auscultatory office systolic blood pressure target between the 50th and 75th percentiles) or intensive treatment (systolic target <40th percentile) by the chief investigator using a rapid, secure, web-based randomisation system. ACE inhibitors or ARBs were used as first-line agents, with the dose titrated every 2-4 weeks to achieve the target blood pressure levels. The primary outcome was mean annual difference in left ventricular mass index (LVMI) by echocardiography measured by a masked observer and was assessed in the intention-to-treat population, defined as all the children who underwent randomisation irrespective of the blood pressure reached. Secondary and safety outcomes were the differences between groups in mean left ventricular relative wall thickness, renal function, and adverse effects and were also assessed in the intention-to-treat population. This trial is registered with ISRCTN, ISRCTN25006406. FINDINGS: Between Oct 30, 2012, and Jan 5, 2017, 64 participants were randomly assigned to the intensive treatment group and 60 to the standard treatment group (median age of participants was 10·0 years [IQR 6·8-12·6], 69 [56%] were male and 107 [86%] were of white ethnicity). Median follow-up was 38·7 months (IQR 28·1-52·2). Blood pressure was lower in the intensive treatment group compared with standard treatment group (mean systolic pressure lower by 4 mm Hg, p=0·0012) but in both groups was close to the 50th percentile. The mean annual reduction in LVMI was similar for intensive and standard treatments (-1·9 g/m2·7 [95% CI -2·4 to -1·3] vs -1·2 g/m2·7 [-1·5 to 0·8], with a treatment effect of -0·7 g/m2·7 [95% CI -1·9 to 2·6] per year; p=0·76) and mean value in both groups at the end of follow-up within the normal range. At baseline, elevated relative wall thickness was more marked than increased LVMI and a reduction in relative wall thickness was greater for the intensive treatment group than for the standard treatment group (-0·010 [95% CI 0·015 to -0·006] vs -0·004 [-0·008 to 0·001], treatment effect -0·020 [95% CI -0·039 to -0·009] per year, p=0·0019). Six (5%) participants reached end-stage kidney disease (ie, an eGFR of <15 mL/min per 1·73 m2; three in each group) during the course of the study. The risk difference between treatment groups was 0·02 (95% CI -0·15 to 0·19, p=0·82) for overall adverse events and 0·07 (-0·05 to 0·19, p=0·25) for serious adverse events. Intensive treatment was not associated with worse renal outcomes or greater adverse effects than standard treatment. INTERPRETATION: These results suggest that cardiac remodelling in children with chronic kidney disease is related to blood pressure control and that a target office systolic blood pressure at the 50th percentile is close to the optimal target for preventing increased left ventricular mass. FUNDING: British Heart Foundation.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Insuficiência Renal Crônica , Masculino , Criança , Humanos , Feminino , Pressão Sanguínea , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/farmacologia , Remodelação Ventricular , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico
2.
Interface Focus ; 1(3): 349-64, 2011 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-22670205

RESUMO

The loss of cardiac pump function accounts for a significant increase in both mortality and morbidity in Western society, where there is currently a one in four lifetime risk, and costs associated with acute and long-term hospital treatments are accelerating. The significance of cardiac disease has motivated the application of state-of-the-art clinical imaging techniques and functional signal analysis to aid diagnosis and clinical planning. Measurements of cardiac function currently provide high-resolution datasets for characterizing cardiac patients. However, the clinical practice of using population-based metrics derived from separate image or signal-based datasets often indicates contradictory treatments plans owing to inter-individual variability in pathophysiology. To address this issue, the goal of our work, demonstrated in this study through four specific clinical applications, is to integrate multiple types of functional data into a consistent framework using multi-scale computational modelling.

3.
J Am Coll Cardiol ; 57(1): 70-5, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21185504

RESUMO

OBJECTIVES: The objective of this study was to compare visual and quantitative analysis of high spatial resolution cardiac magnetic resonance (CMR) perfusion at 3.0-T against invasively determined fractional flow reserve (FFR). BACKGROUND: High spatial resolution CMR myocardial perfusion imaging for the detection of coronary artery disease (CAD) has recently been proposed but requires further clinical validation. METHODS: Forty-two patients (33 men, age 57.4 ± 9.6 years) with known or suspected CAD underwent rest and adenosine-stress k-space and time sensitivity encoding accelerated perfusion CMR at 3.0-T achieving in-plane spatial resolution of 1.2 × 1.2 mm(2). The FFR was measured in all vessels with >50% severity stenosis. Fractional flow reserve <0.75 was considered hemodynamically significant. Two blinded observers visually interpreted the CMR data. Separately, myocardial perfusion reserve (MPR) was estimated using Fermi-constrained deconvolution. RESULTS: Of 126 coronary vessels, 52 underwent pressure wire assessment. Of these, 27 lesions had an FFR <0.75. Sensitivity and specificity of visual CMR analysis to detect stenoses at a threshold of FFR <0.75 were 0.82 and 0.94 (p < 0.0001), respectively, with an area under the receiver-operator characteristic curve of 0.92 (p < 0.0001). From quantitative analysis, the optimum MPR to detect such lesions was 1.58, with a sensitivity of 0.80, specificity of 0.89 (p < 0.0001), and area under the curve of 0.89 (p < 0.0001). CONCLUSIONS: High-resolution CMR MPR at 3.0-T can be used to detect flow-limiting CAD as defined by FFR, using both visual and quantitative analyses.


Assuntos
Circulação Coronária/fisiologia , Estenose Coronária/diagnóstico , Vasos Coronários/patologia , Aumento da Imagem , Imageamento por Ressonância Magnética/métodos , Fluxo Sanguíneo Regional/fisiologia , Estenose Coronária/fisiopatologia , Vasos Coronários/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença
4.
Radiology ; 246(1): 249-57, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17951351

RESUMO

The study was approved by the local ethical committees, and informed consent from each participant was obtained. The purpose of the study was to compare accelerated magnetic resonance (MR) Fourier velocity encoding (FVE), MR phase-contrast velocity mapping, and echocardiography with respect to peak velocity determination in vascular or valvular stenoses. FVE data collection was accelerated by using the k-space and time sensitivity encoding, or k-t SENSE, technique. Peak velocities were evaluated in five healthy volunteers (one woman, four men; mean age, 28 years; range, 23-34 years), three patients with stenotic aortic valves (two women, one man; mean age, 67 years; range, 39-82 years), two patients with pulmonary valvular stenosis (a 14-year-old girl and a 36-year-old man), and two patients with aortic stenosis (two women aged 18 and 27 years). In volunteers, peak velocity determined by the different methods agreed well. In patients, similar peak velocities were obtained by using accelerated MR FVE and echocardiography, while phase-contrast MR imaging results tended to underestimate these values.


Assuntos
Aorta Torácica , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/fisiopatologia , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/fisiopatologia , Imageamento por Ressonância Magnética , Estenose da Valva Pulmonar/diagnóstico por imagem , Estenose da Valva Pulmonar/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico , Arteriopatias Oclusivas/diagnóstico , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Pulmonar/diagnóstico , Ultrassonografia
5.
Oncology ; 73(1-2): 98-103, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18337621

RESUMO

BACKGROUND: The purpose of this study was to investigate whether proteasome inhibition acts as a thermal sensitizing agent to induce tumor cell death in a colon cancer cell line. METHODS: HT-29 colon cancer cells were exposed to hyperthermia (43 degrees C) in the presence of proteasome inhibition for 1 h. Viable cell mass and apoptosis were measured by MTT and annexin V staining, respectively. Protein levels were determined by Western blot analysis. RESULTS: A significant synergistic effect on cell viability with proteasome inhibition was noted under hyperthermic conditions compared to hyperthermia alone (p < 0.05). Increases in phosphorylated ERK and decreases in HSP27 levels were observed in the cells exposed to proteasome inhibition at 43 degrees C. Pretreatment with an inhibitor of ERK yielded an additional increase in apoptosis when used in combination with proteasome inhibition and hyperthermia. Decreased expression of HSP27 by siRNA also resulted in increased thermally induced apoptotic cell death. CONCLUSIONS: Thermal sensitization through proteasome inhibition may represent a novel approach to increase the efficacy of hyperthermia as an anticancer modality.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Neoplasias do Colo/metabolismo , Neoplasias do Colo/terapia , Inibidores Enzimáticos/farmacologia , Proteínas de Choque Térmico/antagonistas & inibidores , Hipertermia Induzida , Inibidores de Proteassoma , Apoptose/efeitos dos fármacos , Western Blotting , Butadienos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/enzimologia , Inibidores de Cisteína Proteinase/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Eletroforese em Gel de Poliacrilamida , Células HT29 , Proteínas de Choque Térmico/genética , Humanos , Leupeptinas/farmacologia , Nitrilas/farmacologia , Inibidores de Proteases/farmacologia , RNA Interferente Pequeno/metabolismo
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