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1.
Kidney Int ; 102(1): 149-159, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35271932

RESUMEN

The benefit and utility of high-sensitivity cardiac troponin (hs-cTn) in the diagnosis of myocardial infarction in patients with kidney impairment is unclear. Here, we describe implementation of hs-cTnI testing on the diagnosis, management, and outcomes of myocardial infarction in patients with and without kidney impairment. Consecutive patients with suspected acute coronary syndrome enrolled in a stepped-wedge, cluster-randomized controlled trial were included in this pre-specified secondary analysis. Kidney impairment was defined as an eGFR under 60mL/min/1.73m2. The index diagnosis and primary outcome of type 1 and type 4b myocardial infarction or cardiovascular death at one year were compared in patients with and without kidney impairment following implementation of hs-cTnI assay with 99th centile sex-specific diagnostic thresholds. Serum creatinine concentrations were available in 46,927 patients (mean age 61 years; 47% women), of whom 9,080 (19%) had kidney impairment. hs-cTnIs were over 99th centile in 46% and 16% of patients with and without kidney impairment. Implementation increased the diagnosis of type 1 infarction from 12.4% to 17.8%, and from 7.5% to 9.4% in patients with and without kidney impairment (both significant). Patients with kidney impairment and type 1 myocardial infarction were less likely to undergo coronary revascularization (26% versus 53%) or receive dual anti-platelets (40% versus 68%) than those without kidney impairment, and this did not change post-implementation. In patients with hs-cTnI above the 99th centile, the primary outcome occurred twice as often in those with kidney impairment compared to those without (24% versus 12%, hazard ratio 1.53, 95% confidence interval 1.31 to 1.78). Thus, hs-cTnI testing increased the identification of myocardial injury and infarction but failed to address disparities in management and outcomes between those with and without kidney impairment.


Asunto(s)
Síndrome Coronario Agudo , Infarto del Miocardio , Insuficiencia Renal , Troponina I , Biomarcadores , Creatinina , Femenino , Humanos , Riñón , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/terapia , Insuficiencia Renal/sangre , Insuficiencia Renal/complicaciones , Insuficiencia Renal/diagnóstico , Troponina I/sangre , Troponina T
2.
Circulation ; 143(23): 2214-2224, 2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-33752439

RESUMEN

BACKGROUND: High-sensitivity cardiac troponin assays enable myocardial infarction to be ruled out earlier, but the safety and efficacy of this approach is uncertain. We investigated whether an early rule-out pathway is safe and effective for patients with suspected acute coronary syndrome. METHODS: We performed a stepped-wedge cluster randomized controlled trial in the emergency departments of 7 acute care hospitals in Scotland. Consecutive patients presenting with suspected acute coronary syndrome between December 2014 and December 2016 were included. Sites were randomized to implement an early rule-out pathway where myocardial infarction was excluded if high-sensitivity cardiac troponin I concentrations were <5 ng/L at presentation. During a previous validation phase, myocardial infarction was ruled out when troponin concentrations were <99th percentile at 6 to 12 hours after symptom onset. The coprimary outcome was length of stay (efficacy) and myocardial infarction or cardiac death after discharge at 30 days (safety). Patients were followed for 1 year to evaluate safety and other secondary outcomes. RESULTS: We enrolled 31 492 patients (59±17 years of age [mean±SD]; 45% women) with troponin concentrations <99th percentile at presentation. Length of stay was reduced from 10.1±4.1 to 6.8±3.9 hours (adjusted geometric mean ratio, 0.78 [95% CI, 0.73-0.83]; P<0.001) after implementation and the proportion of patients discharged increased from 50% to 71% (adjusted odds ratio, 1.59 [95% CI, 1.45-1.75]). Noninferiority was not demonstrated for the 30-day safety outcome (upper limit of 1-sided 95% CI for adjusted risk difference, 0.70% [noninferiority margin 0.50%]; P=0.068), but the observed differences favored the early rule-out pathway (0.4% [57/14 700] versus 0.3% [56/16 792]). At 1 year, the safety outcome occurred in 2.7% (396/14 700) and 1.8% (307/16 792) of patients before and after implementation (adjusted odds ratio, 1.02 [95% CI, 0.74-1.40]; P=0.894), and there were no differences in hospital reattendance or all-cause mortality. CONCLUSIONS: Implementation of an early rule-out pathway for myocardial infarction reduced length of stay and hospital admission. Although noninferiority for the safety outcome was not demonstrated at 30 days, there was no increase in cardiac events at 1 year. Adoption of this pathway would have major benefits for patients and health care providers. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03005158.


Asunto(s)
Infarto del Miocardio/patología , Troponina I/sangre , Adulto , Anciano , Biomarcadores/sangre , Electrocardiografía , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Oportunidad Relativa , Alta del Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Resultado del Tratamiento
3.
J Clin Tuberc Other Mycobact Dis ; 18: 100141, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31890902

RESUMEN

OBJECTIVE: Immunotherapy of tuberculosis (TB) to shorten treatment duration represents an unmet medical need. Orally delivered, tableted TB vaccine (V7) containing heat-killed Mycobacterium vaccae (NCTC 11659) has been demonstrated in prior clinical studies to be safe and fast-acting immune adjunct. METHODS: The outcome of Phase III trial of V7 containing 10 µg of hydrolyzed M. vaccae was evaluated in 152 patients randomized at 2:1 ratio: V7 (N = 100), placebo (N = 52). Both arms received conventional 1st or 2nd line TB drugs co-administered with daily pill of V7 or placebo. RESULTS: After one month mycobacterial clearance was observed in 68% (P < 0.0001) and 23.1% (P = 0.04) of patients on V7 and placebo. Stratified conversion rates in V7 recipients with drug-sensitive and multidrug-resistant TB were 86.7% and 55.6% vs 27.2% and 15% in placebo. Patients on V7 gained on average 2.4 kg (P < 0.0001) vs 0.3 kg (P = 0.18) in placebo. Improvements in hemoglobin levels, erythrocyte sedimentation rate and leukocyte counts were significantly better than in controls. Liver function tests revealed that V7 can prevent chemotherapy-induced hepatic damage. CONCLUSION: Oral M. vaccae is safe, can overcome TB-associated weight loss and inflammation, reduce hepatotoxicity of TB drugs, improve sputum conversion three-fold OR 3.15; 95%CI (2.3,4.6), and cut treatment length by at least six-fold. Longer follow-up studies might be needed to further substantiate our findings (Clinicaltrials.gov: NCT01977768).

4.
Circulation ; 141(3): 161-171, 2020 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-31587565

RESUMEN

BACKGROUND: The introduction of more sensitive cardiac troponin assays has led to increased recognition of myocardial injury in acute illnesses other than acute coronary syndrome. The Universal Definition of Myocardial Infarction recommends high-sensitivity cardiac troponin testing and classification of patients with myocardial injury based on pathogenesis, but the clinical implications of implementing this guideline are not well understood. METHODS: In a stepped-wedge cluster randomized, controlled trial, we implemented a high-sensitivity cardiac troponin assay and the recommendations of the Universal Definition in 48 282 consecutive patients with suspected acute coronary syndrome. In a prespecified secondary analysis, we compared the primary outcome of myocardial infarction or cardiovascular death and secondary outcome of noncardiovascular death at 1 year across diagnostic categories. RESULTS: Implementation increased the diagnosis of type 1 myocardial infarction by 11% (510/4471), type 2 myocardial infarction by 22% (205/916), and acute and chronic myocardial injury by 36% (443/1233) and 43% (389/898), respectively. Compared with those without myocardial injury, the rate of the primary outcome was highest in those with type 1 myocardial infarction (cause-specific hazard ratio [HR] 5.64 [95% CI, 5.12-6.22]), but was similar across diagnostic categories, whereas noncardiovascular deaths were highest in those with acute myocardial injury (cause specific HR 2.65 [95% CI, 2.33-3.01]). Despite modest increases in antiplatelet therapy and coronary revascularization after implementation in patients with type 1 myocardial infarction, the primary outcome was unchanged (cause specific HR 1.00 [95% CI, 0.82-1.21]). Increased recognition of type 2 myocardial infarction and myocardial injury did not lead to changes in investigation, treatment or outcomes. CONCLUSIONS: Implementation of high-sensitivity cardiac troponin assays and the recommendations of the Universal Definition of Myocardial Infarction identified patients at high-risk of cardiovascular and noncardiovascular events but was not associated with consistent increases in treatment or improved outcomes. Trials of secondary prevention are urgently required to determine whether this risk is modifiable in patients without type 1 myocardial infarction. CLINICAL TRIAL REGISTRATION: https://www.clinicaltrials.gov. Unique identifier: NCT01852123.


Asunto(s)
Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Troponina I/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/clasificación , Valor Predictivo de las Pruebas , Medición de Riesgo
5.
J Am Coll Cardiol ; 74(16): 2032-2043, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31623760

RESUMEN

BACKGROUND: Major disparities between women and men in the diagnosis, management, and outcomes of acute coronary syndrome are well recognized. OBJECTIVES: The aim of this study was to evaluate the impact of implementing a high-sensitivity cardiac troponin I assay with sex-specific diagnostic thresholds for myocardial infarction in women and men with suspected acute coronary syndrome. METHODS: Consecutive patients with suspected acute coronary syndrome were enrolled in a stepped-wedge, cluster-randomized controlled trial across 10 hospitals. Myocardial injury was defined as high-sensitivity cardiac troponin I concentration >99th centile of 16 ng/l in women and 34 ng/l in men. The primary outcome was recurrent myocardial infarction or cardiovascular death at 1 year. RESULTS: A total of 48,282 patients (47% women) were included. Use of the high-sensitivity cardiac troponin I assay with sex-specific thresholds increased myocardial injury in women by 42% and in men by 6%. Following implementation, women with myocardial injury remained less likely than men to undergo coronary revascularization (15% vs. 34%) and to receive dual antiplatelet (26% vs. 43%), statin (16% vs. 26%), or other preventive therapies (p < 0.001 for all). The primary outcome occurred in 18% (369 of 2,072) and 17% (488 of 2,919) of women with myocardial injury before and after implementation, respectively (adjusted hazard ratio: 1.11; 95% confidence interval: 0.92 to 1.33), compared with 18% (370 of 2,044) and 15% (513 of 3,325) of men (adjusted hazard ratio: 0.85; 95% confidence interval: 0.71 to 1.01). CONCLUSIONS: Use of sex-specific thresholds identified 5 times more additional women than men with myocardial injury. Despite this increase, women received approximately one-half the number of treatments for coronary artery disease as men, and outcomes were not improved. (High-Sensitivity Troponin in the Evaluation of Patients With Acute Coronary Syndrome [High-STEACS]; NCT01852123).


Asunto(s)
Síndrome Coronario Agudo/sangre , Cardiología/normas , Medición de Riesgo/normas , Factores Sexuales , Troponina I/sangre , Síndrome Coronario Agudo/diagnóstico , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Recurrencia , Valores de Referencia , Resultado del Tratamiento
6.
Lancet ; 392(10151): 919-928, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-30170853

RESUMEN

BACKGROUND: High-sensitivity cardiac troponin assays permit use of lower thresholds for the diagnosis of myocardial infarction, but whether this improves clinical outcomes is unknown. We aimed to determine whether the introduction of a high-sensitivity cardiac troponin I (hs-cTnI) assay with a sex-specific 99th centile diagnostic threshold would reduce subsequent myocardial infarction or cardiovascular death in patients with suspected acute coronary syndrome. METHODS: In this stepped-wedge, cluster-randomised controlled trial across ten secondary or tertiary care hospitals in Scotland, we evaluated the implementation of an hs-cTnI assay in consecutive patients who had been admitted to the hospitals' emergency departments with suspected acute coronary syndrome. Patients were eligible for inclusion if they presented with suspected acute coronary syndrome and had paired cardiac troponin measurements from the standard care and trial assays. During a validation phase of 6-12 months, results from the hs-cTnI assay were concealed from the attending clinician, and a contemporary cardiac troponin I (cTnI) assay was used to guide care. Hospitals were randomly allocated to early (n=5 hospitals) or late (n=5 hospitals) implementation, in which the high-sensitivity assay and sex-specific 99th centile diagnostic threshold was introduced immediately after the 6-month validation phase or was deferred for a further 6 months. Patients reclassified by the high-sensitivity assay were defined as those with an increased hs-cTnI concentration in whom cTnI concentrations were below the diagnostic threshold on the contemporary assay. The primary outcome was subsequent myocardial infarction or death from cardiovascular causes at 1 year after initial presentation. Outcomes were compared in patients reclassified by the high-sensitivity assay before and after its implementation by use of an adjusted generalised linear mixed model. This trial is registered with ClinicalTrials.gov, number NCT01852123. FINDINGS: Between June 10, 2013, and March 3, 2016, we enrolled 48 282 consecutive patients (61 [SD 17] years, 47% women) of whom 10 360 (21%) patients had cTnI concentrations greater than those of the 99th centile of the normal range of values, who were identified by the contemporary assay or the high-sensitivity assay. The high-sensitivity assay reclassified 1771 (17%) of 10 360 patients with myocardial injury or infarction who were not identified by the contemporary assay. In those reclassified, subsequent myocardial infarction or cardiovascular death within 1 year occurred in 105 (15%) of 720 patients in the validation phase and 131 (12%) of 1051 patients in the implementation phase (adjusted odds ratio for implementation vs validation phase 1·10, 95% CI 0·75 to 1·61; p=0·620). INTERPRETATION: Use of a high-sensitivity assay prompted reclassification of 1771 (17%) of 10 360 patients with myocardial injury or infarction, but was not associated with a lower subsequent incidence of myocardial infarction or cardiovascular death at 1 year. Our findings question whether the diagnostic threshold for myocardial infarction should be based on the 99th centile derived from a normal reference population. FUNDING: The British Heart Foundation.


Asunto(s)
Síndrome Coronario Agudo/diagnóstico , Infarto del Miocardio/diagnóstico , Troponina I/sangre , Síndrome Coronario Agudo/sangre , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Valor Predictivo de las Pruebas
7.
Clin Chem Lab Med ; 55(9): 1397-1406, 2017 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-28426429

RESUMEN

BACKGROUND: B-type natriuretic peptide (BNP) is a 32 amino acid cardiac hormone routinely measured by immunoassays to diagnose heart failure. While it is reported that immunoassay results can vary up to 45%, no attempt of standardization and/or harmonization through the development of certified reference materials (CRMs) or reference measurement procedures (RMPs) has yet been carried out. METHODS: B-type natriuretic peptide primary calibrator was quantified traceably to the International System of Units (SI) by both amino acid analysis and tryptic digestion. A method for the stabilization of BNP in plasma followed by protein precipitation, solid phase extraction (SPE) and liquid chromatography (LC) mass spectrometry (MS) was then developed and validated for the quantification of BNP at clinically relevant concentrations (15-150 fmol/g). RESULTS: The candidate reference method was applied to the quantification of BNP in a number of samples from the UK NEQAS Cardiac Markers Scheme to demonstrate its applicability to generate reference values and to preliminary evaluate the commutability of a potential CRM. The results from the reference method were consistently lower than the immunoassay results and discrepancy between the immunoassays was observed confirming previous data. CONCLUSIONS: The application of the liquid chromatography-mass spectrometry (LC-MS) method to the UK NEQAS samples and the correlation of the results with the immunoassay results shows the potential of the method to support external quality assessment schemes, to improve understanding of the bias of the assays and to establish RMPs for BNP measurements. Furthermore, the method has the potential to be multiplexed for monitoring circulating truncated forms of BNP.


Asunto(s)
Péptido Natriurético Encefálico/sangre , Biomarcadores/sangre , Cromatografía Liquida , Humanos , Inmunoensayo , Espectrometría de Masas , Péptido Natriurético Encefálico/aislamiento & purificación , Extracción en Fase Sólida
8.
J Hepatocell Carcinoma ; 4: 59-69, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28443252

RESUMEN

BACKGROUND: An increasing number of studies is now devoted to immunotherapy of cancer. We evaluated the clinical benefit of hepcortespenlisimut-L (Hepko-V5 [formerly known as V5])-an oral therapeutic vaccine designated by the United States Food and Drug Administration (FDA) as an orphan drug for treatment of hepatocellular carcinoma (HCC). V5 was initially developed by us in 2002 to treat hepatitis B or C viral infections and liver cirrhosis. METHODS: The outcome of open-label Phase II trial of daily dose of V5 pill was analyzed retrospectively. Over a period of 5 years, 75 patients with advanced HCC were enrolled, consisting of 29 (38.7%) females and 46 (61.3%) males with a median age of 60 years (mean 61.6±8.1 years). Out of these, 23 (30.7%) had hepatitis B and 34 (45.3%) had hepatitis C infections, including 9 (12%) with dual infection, 4 (5.3%) negative for both viruses, and 5 (6.7%) without established viral diagnosis. Most patients (94.7%) had underlying liver cirrhosis of varying severity. RESULTS: After a median of 2 months of treatment, 50 out of 75 patients had experienced a decline in serum levels of the tumor marker, alpha-fetoprotein (AFP) (66.7%; P=0.006 by Wilcoxon signed rank test). Baseline median AFP levels were 245.2 IU/mL (mean 4,233; range 7.2-92,407; 95% confidence interval [CI] 1,186-7,280) and post-treatment values were 102.3 IU/mL (mean 2,539; range 0.9-54,478; 95% CI 503-4,575). The decrease in AFP was correlated either with tumor clearance or regression on computed tomography scans. The median overall survival time could not be established since 68 out of 75 (90.7%) patients were still alive after median follow-up of 12 months (mean 15±9.7; range 7-59; 95% CI 12.8-17.2). The first patient in this study received immunotherapy 5 years ago and still remains in complete remission. None of the patients experienced any serious adverse effects or toxicity. CONCLUSION: The results indicate that hepcortespenlismut-L is a safe, effective, and fast-acting immunomodulatory intervention for HCC. The Phase III, randomized, double-blind, placebo-controlled trial is now initiated at the Mongolian National Cancer Center to confirm these promising findings.

9.
Lancet ; 386(10012): 2481-8, 2015 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-26454362

RESUMEN

BACKGROUND: Suspected acute coronary syndrome is the commonest reason for emergency admission to hospital and is a large burden on health-care resources. Strategies to identify low-risk patients suitable for immediate discharge would have major benefits. METHODS: We did a prospective cohort study of 6304 consecutively enrolled patients with suspected acute coronary syndrome presenting to four secondary and tertiary care hospitals in Scotland. We measured plasma troponin concentrations at presentation using a high-sensitivity cardiac troponin I assay. In derivation and validation cohorts, we evaluated the negative predictive value of a range of troponin concentrations for the primary outcome of index myocardial infarction, or subsequent myocardial infarction or cardiac death at 30 days. This trial is registered with ClinicalTrials.gov (number NCT01852123). FINDINGS: 782 (16%) of 4870 patients in the derivation cohort had index myocardial infarction, with a further 32 (1%) re-presenting with myocardial infarction and 75 (2%) cardiac deaths at 30 days. In patients without myocardial infarction at presentation, troponin concentrations were less than 5 ng/L in 2311 (61%) of 3799 patients, with a negative predictive value of 99·6% (95% CI 99·3-99·8) for the primary outcome. The negative predictive value was consistent across groups stratified by age, sex, risk factors, and previous cardiovascular disease. In two independent validation cohorts, troponin concentrations were less than 5 ng/L in 594 (56%) of 1061 patients, with an overall negative predictive value of 99·4% (98·8-99·9). At 1 year, these patients had a lower risk of myocardial infarction and cardiac death than did those with a troponin concentration of 5 ng/L or more (0·6% vs 3·3%; adjusted hazard ratio 0·41, 95% CI 0·21-0·80; p<0·0001). INTERPRETATION: Low plasma troponin concentrations identify two-thirds of patients at very low risk of cardiac events who could be discharged from hospital. Implementation of this approach could substantially reduce hospital admissions and have major benefits for both patients and health-care providers. FUNDING: British Heart Foundation and Chief Scientist Office (Scotland).


Asunto(s)
Síndrome Coronario Agudo/diagnóstico , Infarto del Miocardio/diagnóstico , Troponina I/sangre , Síndrome Coronario Agudo/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Escocia , Sensibilidad y Especificidad
10.
BMJ ; 350: g7873, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25609052

RESUMEN

OBJECTIVE: To evaluate the diagnosis of myocardial infarction using a high sensitivity troponin I assay and sex specific diagnostic thresholds in men and women with suspected acute coronary syndrome. DESIGN: Prospective cohort study. SETTING: Regional cardiac centre, United Kingdom. PARTICIPANTS: Consecutive patients with suspected acute coronary syndrome (n=1126, 46% women). Two cardiologists independently adjudicated the diagnosis of myocardial infarction by using a high sensitivity troponin I assay with sex specific diagnostic thresholds (men 34 ng/L, women 16 ng/L) and compared with current practice where a contemporary assay (50 ng/L, single threshold) was used to guide care. MAIN OUTCOME MEASURE: Diagnosis of myocardial infarction. RESULTS: The high sensitivity troponin I assay noticeably increased the diagnosis of myocardial infarction in women (from 11% to 22%; P<0.001) but had a minimal effect in men (from 19% to 21%, P=0.002). Women were less likely than men to be referred to a cardiologist or undergo coronary revascularisation (P<0.05 for both). At 12 months, women with undisclosed increases in troponin concentration (17-49 ng/L) and those with myocardial infarction (≥50 ng/L) had the highest rate of death or reinfarction compared with women without (≤16 ng/L) myocardial infarction (25%, 24%, and 4%, respectively; P<0.001). CONCLUSIONS: Although having little effect in men, a high sensitivity troponin assay with sex specific diagnostic thresholds may double the diagnosis of myocardial infarction in women and identify those at high risk of reinfarction and death. Whether use of sex specific diagnostic thresholds will improve outcomes and tackle inequalities in the treatment of women with suspected acute coronary syndrome requires urgent attention.


Asunto(s)
Síndrome Coronario Agudo/sangre , Infarto del Miocardio/sangre , Troponina I/sangre , Síndrome Coronario Agudo/diagnóstico , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Estudios Prospectivos , Curva ROC , Valores de Referencia , Sensibilidad y Especificidad , Factores Sexuales
11.
Bioorg Med Chem Lett ; 22(12): 3879-83, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-22608965

RESUMEN

A novel, potent and selective quinazolinone series of inhibitors of p38α MAP kinase has been identified. Modifications designed to address the issues of poor aqueous solubility and high plasma protein binding as well as embedded aniline functionalities resulted in the identification of a clinical candidate N-cyclopropyl-4-methyl-3-[6-(4-methylpiperazin-1-yl)-4-oxoquinazolin-3(4H)-yl]benzamide (AZD6703). Optimisation was guided by understanding of the binding modes from X-ray crystallographic studies which showed a switch from DFG 'out' to DFG 'in' as the inhibitor size was reduced to improve overall properties.


Asunto(s)
Antiinflamatorios no Esteroideos/síntesis química , Proteína Quinasa 14 Activada por Mitógenos/antagonistas & inhibidores , Piperazinas/síntesis química , Inhibidores de Proteínas Quinasas/síntesis química , Animales , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Proteínas Sanguíneas/química , Cristalografía por Rayos X , Perros , Descubrimiento de Drogas , Humanos , Inflamación/tratamiento farmacológico , Proteína Quinasa 14 Activada por Mitógenos/metabolismo , Modelos Moleculares , Peso Molecular , Piperazinas/química , Piperazinas/farmacología , Unión Proteica , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Ratas , Solubilidad , Relación Estructura-Actividad
12.
Ann Biomed Eng ; 36(2): 185-94, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18080835

RESUMEN

The effective treatment of cartilage defects by tissue engineering requires an improved understanding of the effect of mechanical forces on cell differentiation within three-dimensional (3D) matrices. The objective of this study was to investigate the effects of mechanical constraint and cyclic tensile strain on the chondrogenic differentiation of mesenchymal stem cells (MSCs) in a 3D collagen type I-glycosaminoglycan (GAG) scaffold. A multi-station uniaxial stretching bioreactor was fabricated to facilitate application of cyclic strain to the constructs cultured in a chondrogenic medium. Mechanical constraint, created by uniaxial clamping, prevented the cell-mediated contraction of the scaffolds and resulted in a reduction in the rate of GAG synthesis as measured by [35S] sulfate incorporation relative to unconstrained controls. However, the rate of GAG synthesis was increased following application of continuous 10% cyclic tensile loading at 1 Hz for 7 days. A poroelastic finite element analysis of the 3D scaffold computed a maximum fluid flow of 19 microm/s and maximum principal strains of 8% under 10% stretch suggesting these magnitudes were sufficient to mechano-regulate the chondrogenic differentiation process.


Asunto(s)
Condrocitos/citología , Condrocitos/fisiología , Condrogénesis/fisiología , Colágeno Tipo I/fisiología , Glicosaminoglicanos/fisiología , Mecanotransducción Celular/fisiología , Células Madre Mesenquimatosas/citología , Modelos Biológicos , Animales , Diferenciación Celular/fisiología , Células Cultivadas , Simulación por Computador , Masculino , Células Madre Mesenquimatosas/fisiología , Ratas , Ratas Wistar , Resistencia a la Tracción
13.
Interact Cardiovasc Thorac Surg ; 5(3): 217-21, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17670550

RESUMEN

Although hypothermia and ischaemic preconditioning (IP) are independently recognised mechanisms of cardioprotection, interactions between myocardial temperature and preconditioning have not been investigated. Therefore, this study explored the possibility of inducing IP during hypothermia and quantifying its effects at two temperature regimens commonly used in clinical practice. One hundred and four patients undergoing coronary artery bypass grafting (CABG) with intermittent cross-clamping and ventricular fibrillation were randomised to four groups: N=normothermia (36.5+/-0.5 degrees C); NP=normothermia+preconditioning, H=hypothermia (31.5+/-0.5 degrees C), HP=hypothermia+preconditioning. The primary outcome measure was release of cardiac Troponin I (cTnI), measured at 6 time points from pre- to 72 h after the end of CPB. There were no hospital deaths and no significant differences in pre- and intra-operative variables (P>or=0.05). There were significant differences in cTnI release between all groups, as follows: N: 117+/-12 microg/l (P

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