ABSTRACT
Data are limited on the impact of commencing antiplatelet therapy on von Willebrand Factor Antigen (VWF:Ag) or von Willebrand Factor propeptide (VWFpp) levels and ADAMTS13 activity, and their relationship with platelet reactivity following TIA/ischaemic stroke. In this pilot, observational study, VWF:Ag and VWFpp levels and ADAMTS13 activity were quantified in 48 patients ≤4 weeks of TIA/ischaemic stroke (baseline), and 14 days (14d) and 90 days (90d) after commencing aspirin, clopidogrel or aspirin+dipyridamole. Platelet reactivity was assessed at moderately-high shear stress (PFA-100® Collagen-Epinephrine / Collagen-ADP / INNOVANCE PFA P2Y assays), and low shear stress (VerifyNow® Aspirin / P2Y12, and Multiplate® Aspirin / ADP assays). VWF:Ag levels decreased and VWFpp/VWF:Ag ratio increased between baseline and 14d and 90d in the overall population (P ≤ 0.03). In the clopidogrel subgroup, VWF:Ag levels decreased and VWFpp/VWF:Ag ratio increased between baseline and 14d and 90d (P ≤ 0.01), with an increase in ADAMTS13 activity between baseline vs. 90d (P ≤ 0.03). In the aspirin+dipyridamole subgroup, there was an inverse relationship between VWF:Ag and VWFpp levels with both PFA-100 C-ADP and INNOVANCE PFA P2Y closure times (CTs) at baseline (P ≤ 0.02), with PFA-100 C-ADP, INNOVANCE PFA P2Y and C-EPI CTs at 14d (P ≤ 0.05), and between VWF:Ag levels and PFA-100 INNOVANCE PFA P2Y CTs at 90d (P = 0.03). There was a positive relationship between ADAMTS13 activity and PFA-100 C-ADP CTs at baseline (R2 = 0.254; P = 0.04). Commencing/altering antiplatelet therapy, mainly attributed to commencing clopidogrel in this study, was associated with decreasing endothelial activation following TIA/ischaemic stroke. These data enhance our understanding of the impact of VWF:Ag and VWFpp especially on ex-vivo platelet reactivity status at high shear stress after TIA/ischaemic stroke.
ABSTRACT
BACKGROUND: Data are limited on the ability of dipyridamole to additionally inhibit platelet function/reactivity in ischaemic cerebrovascular disease (CVD) patients on aspirin. AIMS: To assess inhibition of platelet function/reactivity and platelet activation with dipyridamole in CVD. METHODS: This prospective, observational study assessed TIA/ischaemic stroke patients before (baseline; N = 60), at 14 ±7 days (14d, N = 39) and ≥ 90 days (90d, N = 31) after adding dipyridamole to aspirin. Platelet function/reactivity at high shear stress (PFA-100® C-ADP) and low shear stress (VerifyNow® P2Y12 and Multiplate® ADP assays), and platelet activation status (% expression of CD62P, CD63 and leucocyte-platelet complexes on whole blood flow cytometry) were quantified. 'Dipyridamole-high on-treatment platelet reactivity (HTPR)' was defined as failure to inhibit ADP-induced platelet aggregation +/- adhesion compared with the patient's baseline on aspirin monotherapy by more than twice the coefficient-of-variation of the assay after adding dipyridamole to aspirin. RESULTS: Dipyridamole-HTPR was identified in 71.4-75% of patients on PFA-100 C-ADP, 83.9-86.8% of patients on VerifyNow P2Y12, and 81.5-83.3% of patients on Multiplate ADP assays. There were no changes in CD62P/CD63 expression (P ≥ 0.18), or consistent changes in leucocyte-platelet complexes in CVD patients overall at 14d or 90d vs. baseline after commencing dipyridamole. Monocyte-platelet complexes increased in the patient subgroup with dipyridamole-HTPR at 14d and 90d on PFA-100, and at 14d on VerifyNow (P ≤ 0.04), but not in those without dipyridamole-HTPR. DISCUSSION: Additional antiplatelet effects of dipyridamole are detectable under high and low shear stress conditions with user-friendly platelet function/reactivity tests ex vivo. Increasing circulating monocyte-platelet complexes over time are associated with dipyridamole-HTPR.
Subject(s)
Brain Ischemia , Ischemic Attack, Transient , Ischemic Stroke , Stroke , Adenosine Diphosphate/metabolism , Adenosine Diphosphate/pharmacology , Aspirin/pharmacology , Aspirin/therapeutic use , Blood Platelets , Brain Ischemia/metabolism , Dipyridamole/metabolism , Dipyridamole/pharmacology , Dipyridamole/therapeutic use , Humans , Ischemic Attack, Transient/drug therapy , Platelet Activation , Platelet Aggregation Inhibitors/pharmacology , Platelet Aggregation Inhibitors/therapeutic use , Prospective StudiesABSTRACT
Information regarding the profile of reticulated platelets (RP) in ischemic cerebrovascular disease (CVD) patients is limited. Data from two prospective, observational, case-control studies were combined to compare the %RP using whole blood flow cytometry in patients ≤ 4 weeks of TIA/stroke onset (baseline, N = 210), and 14 ±7 days (14d, N = 182) and ≥ 90 days (90d, N = 145) after starting or changing antiplatelet therapy with healthy controls (N = 34). There were no differences in median %RP between the overall CVD patient population at baseline or 14d vs. controls (P ≥ 0.2). However, the median %RP was significantly higher in CVD patients overall at 90d (P = .036), and in the subgroup of patients with "lacunar" TIA/ischemic stroke at baseline (P = .04) and at 90d (P = .01), but not at 14d (P = .06) vs. controls. There were no significant differences in the median %RP between other TIA/stroke subgroups and controls (P ≥ 0.05). Elevated circulating reticulated platelets, as a marker of increased platelet production/turnover, may occur following an ischemic event in a well-phenotyped TIA/ischemic stroke population overall, but may precede symptom onset at least in the subgroup with small vessel occlusion. These data improve our understanding of the profile of reticulated platelets in CVD patients.
Subject(s)
Blood Platelets/metabolism , Ischemic Attack, Transient/blood , Case-Control Studies , Humans , Prospective StudiesABSTRACT
BACKGROUND: Despite the established evidence and theoretical advances explaining human judgments under uncertainty, developments of mobile health (mHealth) Clinical Decision Support Systems (CDSS) have not explicitly applied the psychology of decision making to the study of user needs. We report on a user needs approach to develop a prototype of a mHealth CDSS for Parkinson's disease (PD), which is theoretically grounded in the psychological literature about expert decision making and judgement under uncertainty. METHODS: A suite of user needs studies was conducted in 4 European countries (Greece, Italy, Slovenia, the UK) prior to the development of PD_Manager, a mHealth-based CDSS designed for Parkinson's disease, using wireless technology. Study 1 undertook Hierarchical Task Analysis (HTA) including elicitation of user needs, cognitive demands and perceived risks/benefits (ethical considerations) associated with the proposed CDSS, through structured interviews of prescribing clinicians (N = 47). Study 2 carried out computational modelling of prescribing clinicians' (N = 12) decision strategies based on social judgment theory. Study 3 was a vignette study of prescribing clinicians' (N = 18) willingness to change treatment based on either self-reported symptoms data, devices-generated symptoms data or combinations of both. RESULTS: Study 1 indicated that system development should move away from the traditional silos of 'motor' and 'non-motor' symptom evaluations and suggest that presenting data on symptoms according to goal-based domains would be the most beneficial approach, the most important being patients' overall Quality of Life (QoL). The computational modelling in Study 2 extrapolated different factor combinations when making judgements about different questions. Study 3 indicated that the clinicians were equally likely to change the care plan based on information about the change in the patient's condition from the patient's self-report and the wearable devices. CONCLUSIONS: Based on our approach, we could formulate the following principles of mHealth design: 1) enabling shared decision making between the clinician, patient and the carer; 2) flexibility that accounts for diagnostic and treatment variation among clinicians; 3) monitoring of information integration from multiple sources. Our approach highlighted the central importance of the patient-clinician relationship in clinical decision making and the relevance of theoretical as opposed to algorithm (technology)-based modelling of human judgment.
Subject(s)
Clinical Decision-Making , Decision Support Systems, Clinical , Health Personnel/psychology , Parkinson Disease/prevention & control , Telemedicine , Greece , Humans , Italy , Judgment , Models, Theoretical , Psychological Theory , Slovenia , United KingdomABSTRACT
BACKGROUND: Axillary hyperhidrosis is a common complaint affecting 5% of the general population. It can significantly impact quality of life (QOL) and may be extremely debilitating. Administration of intra-dermal botulinum toxin type-A (Botox) has been proven to be effective in managing axillary hyperhidrosis; however, to date, no long-term data has assessed its efficacy. AIM: We aim to assess long-term (> 5 years) QOL outcomes in this patient cohort. METHODS: In this single-centre series, all patients attending for axillary botox, with five or more years of follow-up, were prospectively included. QOL was assessed in all patients using the validated assessment tool, the modified Dermatology Life Quality Index (DLQI). Standard statistical methods were utilised with data reported as mean (± standard deviation). Subgroup analysis utilising previously published departmental data allowed for further assessment of change in QOL over time. RESULTS: A total of 75 patients (83% female) met the inclusion criteria with 67% completing the DLQI assessment. Follow-up ranged from 5 to 10 years with a mean age of 37.6 years (± 8.82). The mean number of treatments over the study period was 12 (± 3.1). Mean overall post-treatment DLQI score was 1.6 (± 2.01). This represented a significant improvement in patient QOL (p = < 0.0001) associated with long-term botox application. This statistical significance was identified consistently across all components of the DLQI tool. CONCLUSION: These data suggest that the established early QOL benefits associated with intra-dermal botox administration for AH are sustained in the long term. This benefit was seen across all subsets of the DLQI tool.
Subject(s)
Axilla/abnormalities , Botulinum Toxins, Type A/therapeutic use , Hyperhidrosis/drug therapy , Adult , Female , Follow-Up Studies , Humans , Injections, Intradermal , Male , Time Factors , Treatment OutcomeABSTRACT
BACKGROUND: Given the importance of habitual dietary protein intake, distribution patterns and dietary sources in the aetiology of age-related declines of muscle mass and function, the present study examined these factors as a function of sex and age in Irish adults aged 18-90 years comprising The National Adult Nutrition Survey (NANS). METHODS: In total, 1051 (males, n = 523; females, n = 528) undertook a 4-day semi-weighed food diary. Total, body mass relative intake and percentage contribution to total energy intake of dietary protein were determined in addition to protein distribution scores (PDS), as well as the contribution of food groups, animal- and plant-based foods to total protein intake. RESULTS: Total and relative protein intake [mean (SD)] were highest in those aged 18-35 years [96 (3) g day-1 , 1.32 (0.40) g kg-1 day-1 ], with lower protein intakes with increasing age (i.e. in adults aged ≥65 years [82 (22) g, 1.15 (0.34) g kg-1 day-1 , P < 0.001 for both]. Differences in protein intake between age groups were more pronounced in males compared to females. Protein distribution followed a skewed pattern for all age groups [breakfast, 15 (10) g; lunch, 30 (15) g; dinner, 44 (17) g]. Animal-based foods were the dominant protein source within the diet [63% (11%) versus 37% (11%) plant protein, P < 0.001]. CONCLUSIONS: Protein intake and the number of meals reaching the purported threshold for maximising post-prandial anabolism were highest in young adults, and lower with increasing age. For main meals, breakfast provided the lowest quantity of protein across all age categories and may represent an opportunity for improving protein distribution, whereas, in older adults, increasing the number of meals reaching the anabolic threshold regardless of distribution pattern may be more appropriate.
Subject(s)
Age Distribution , Diet/statistics & numerical data , Dietary Proteins/analysis , Sex Distribution , Adolescent , Adult , Aged , Aged, 80 and over , Animal Proteins, Dietary/analysis , Diet Records , Energy Intake , Feeding Behavior , Female , Humans , Ireland , Male , Meals , Middle Aged , Nutrition Surveys , Plant Proteins, Dietary/analysis , Young AdultABSTRACT
BACKGROUND: This longitudinal study examined the profile and pregnancy-related behaviours of women who reported smoking in two successive pregnancies when they presented for prenatal care in a large maternity hospital. METHODS: Using the hospital electronic medical records, women who delivered two successive singleton pregnancies during the years 2011-15 were analyzed. Standardized data were computerized by a midwife at the first prenatal visit, following delivery and before discharge. RESULTS: Over the 5 years, 6647 women delivered twice. Overall 5754 (86.6%) were persistent non-smokers in both pregnancies, 609 (9.2%) were persistent smokers in both pregnancies and between pregnancies 202 (3.0%) quit and 82 (1.2%) started smoking. Compared with persistent non-smokers, persistent smokers had higher rates of reported illicit drug use, alcohol consumption and psychological problems and lower rates of planned pregnancy, folic acid supplementation and breastfeeding in both pregnancies (all P < 0.001). In persistent smokers, folic acid supplementation practices deteriorated and illicit drug use increased in the subsequent pregnancy. CONCLUSIONS: We found that approximately one in 10 women smoked in two consecutive pregnancies. Furthermore, compared with non-smokers, persistent smokers were more likely to report other health behaviours associated with adverse pregnancy outcomes and may require additional multidisciplinary support.
Subject(s)
Smoking Cessation , Smoking , Female , Humans , Longitudinal Studies , Pregnancy , Pregnancy Outcome , Prenatal Care , Smoking/epidemiologyABSTRACT
BACKGROUND: Assessment of 'high on-treatment platelet reactivity (HTPR)' could enhance understanding of the pathophysiology of first or recurrent vascular events in carotid stenosis patients on antiplatelet therapy. METHODS: This prospective, multi-centre study assessed antiplatelet-HTPR status and its relationship with micro-emboli signals (MES) in asymptomatic vs. symptomatic ≥ 50-99% carotid stenosis. Platelet function/reactivity was assessed under 'moderately high shear stress' with the PFA-100® and 'low shear stress' with VerifyNow® and Multiplate® analysers. Bilateral 1-h transcranial Doppler ultrasound of the middle cerebral arteries classified patients as MES + ve or MES - ve. RESULTS: Data from 34 asymptomatic patients were compared with 43 symptomatic patients in the 'early phase' (≤ 4 weeks) and 37 patients in the 'late phase' (≥ 3 months) after TIA/ischaemic stroke. Median daily aspirin doses were higher in early symptomatic (225 mg; P < 0.001), but not late symptomatic (75 mg; P = 0.62) vs. asymptomatic patients (75 mg). There was a lower prevalence of aspirin-HTPR in early (28.6%; P = 0.028), but not late symptomatic (38.9%; P = 0.22) compared with asymptomatic patients (56.7%) on the PFA-100®, but not on the VerifyNow® or Multiplate® (P ≤ 0.53). Early symptomatic patients had a higher prevalence of aspirin-HTPR on the PFA-100® (28.6%) vs. VerifyNow® (9.5%; P = 0.049), but not Multiplate® assays (11.9%, P = 0.10). There was no difference in aspirin-HTPR prevalence between any symptomatic vs. asymptomatic MES + ve or MES - ve subgroup. DISCUSSION: Recently symptomatic moderate-severe carotid stenosis patients had a lower prevalence of aspirin-HTPR than their asymptomatic counterparts on the PFA-100®, likely related to higher aspirin doses. The prevalence of antiplatelet-HTPR was positively influenced by higher shear stress levels, but not MES status.
Subject(s)
Aspirin/pharmacology , Blood Platelets , Carotid Stenosis/drug therapy , Intracranial Embolism/drug therapy , Platelet Aggregation Inhibitors/pharmacology , Aged , Aspirin/administration & dosage , Blood Platelets/drug effects , Blood Platelets/physiology , Brain Ischemia/drug therapy , Carotid Stenosis/diagnostic imaging , Female , Humans , Intracranial Embolism/diagnostic imaging , Male , Middle Aged , Middle Cerebral Artery/diagnostic imaging , Platelet Aggregation Inhibitors/administration & dosage , Prospective Studies , Stroke/drug therapy , Ultrasonography, Doppler, TranscranialABSTRACT
OBJECTIVES: To investigate the impact of a six-month multi-ingredient nutrition supplement intervention (Smartfish®), containing omega-3 polyunsaturated fatty acids (PUFAs), vitamin D, resveratrol, and whey protein, on cognitive function in Irish older adults. DESIGN: Double-blind, randomised controlled trial (ClinicalTrials.gov: NCT02001831). A quantitative, mixed-model design was employed in which the dependent variable (cognitive function) was analysed with a between-subjects factor of group (placebo, intervention) and within-subjects factor of testing occasion (baseline, three-months, six-months). SETTING: Community-based intervention including assessments conducted at University College Dublin, Ireland. PARTICIPANTS: Thirty-seven community-dwelling older adults (68-83 years; mean (xÌ)= 75.14 years; standard deviation (SD)= 3.64; 18 males) with normal cognitive function (>24 on the Mini Mental State Examination) were assigned to the placebo (n= 17) or intervention (n= 20) via a block randomisation procedure. INTERVENTION: Daily consumption for six-months of a 200mL liquid juice intervention comprising 3000mg omega-3 PUFAs [1500mg docosahexaenoic acid (DHA) and 1500mg eicosapentaenoic acid (EPA)], 10µg vitamin D3, 150mg resveratrol and 8g whey protein isolate. The placebo contained 200mL juice only. MEASUREMENTS: A standardised cognitive assessment battery was conducted at baseline and follow-ups. Individual test scores were z-transformed to generate composite scores grouped into cognitive domains: executive function, memory, attention and sensorimotor speed. Motor imagery accuracy and subjective awareness of cognitive failures variables were computed from raw scores. RESULTS: A hierarchical statistical approach was used to analyse the data; first, by examining overall cognitive function, then by domain, and then by individual test scores. Using mixed between-within subjects, analyses of variance (ANOVAs), no significant differences in overall cognitive function or composite cognitive domains were observed between groups over time. The only significant interaction was for Stroop Color-Word Time (p< 0.05). The intervention group demonstrated reduced task completion time at three- and six-month follow-ups, indicating enhanced performance. CONCLUSION: The present nutrition intervention encompassed a multi-ingredient approach targeted towards improving cognitive function, but overall had only a limited beneficial impact in the older adult sample investigated. Future investigations should seek to establish any potential clinical applications of such targeted interventions with longer durations of supplementation, or in populations with defined cognitive deficits.
Subject(s)
Cognition/drug effects , Fatty Acids, Omega-3/pharmacology , Resveratrol/pharmacology , Vitamin D/pharmacology , Whey Proteins/pharmacology , Aged , Aged, 80 and over , Dietary Supplements , Double-Blind Method , Female , Humans , Male , Neuropsychological TestsABSTRACT
There is international consensus that smoking cessation in the first half of pregnancy improves foetal outcomes. We surveyed all 19 maternity units nationally about their antenatal smoking cessation practices. All units recorded details on maternal smoking at the first antenatal visit. Only one unit validated the self-reported smoking status of pregnant women using a carbon monoxide breath test. Twelve units (63%) recorded timing of smoking cessation. In all units women who reported smoking were given verbal cessation advice. This was supported by written advice in 12 units (63%), but only six units (32%) had all midwives trained to provide this advice. Only five units (26%) reported routinely revisiting smoking status later in pregnancy. Although smoking is an important modifiable risk factor for adverse pregnancy outcomes, smoking cessation services are inadequate in the Irish maternity services and there are variations in practices between hospitals.
Subject(s)
Pregnant Women , Smoking Cessation/statistics & numerical data , Smoking Prevention/statistics & numerical data , Smoking , Female , Humans , Ireland , Pregnancy , Prenatal Care/standards , Prenatal Care/statistics & numerical dataABSTRACT
INTRODUCTION: Von Willebrand factor propeptide (VWF:Ag II) is proposed to be a more sensitive marker of acute endothelial activation than von Willebrand factor antigen (VWF:Ag). Simultaneous data on VWF:Ag and VWF:Ag II profiles are very limited following TIA and ischaemic stroke. METHODS: In this prospective, observational, case-control study, plasma VWF:Ag and VWF:Ag II levels were quantified in 164 patients≤4weeks of TIA or ischaemic stroke (baseline), and then ≥14days (14d) and ≥90days (90d) later, and compared with those from 27 healthy controls. TIA and stroke subtyping was performed according to the TOAST classification. The relationship between VWF:Ag and VWF:Ag II levels and platelet activation status was assessed. RESULTS: 'Unadjusted' VWF:Ag and VWF:Ag II levels were higher in patients at baseline, 14d and 90d than in controls (p≤0.03). VWF:Ag levels remained higher in patients than controls at baseline (p≤0.03), but not at 14d or 90d after controlling for differences in age or hypertension, and were higher in patients at baseline and 90d after controlling for smoking status (p≤0.04). 'Adjusted' VWF:Ag II levels were not higher in patients than controls after controlling for age, hypertension or smoking (p≥0.1). Patients with symptomatic carotid stenosis (N=46) had higher VWF:Ag and VWF:Ag II levels than controls at all time-points (p≤0.002). There was no significant correlation between platelet activation status and VWF:Ag or VWF:Ag II levels. CONCLUSIONS: VWF:Ag and VWF:Ag II levels are increased in an overall TIA and ischaemic stroke population, especially in patients with recently symptomatic carotid stenosis. VWF:Ag II was not superior to VWF:Ag at detecting acute endothelial activation in this cohort and might reflect timing of blood sampling in our study.
Subject(s)
Ischemic Attack, Transient/blood , Protein Precursors/blood , Stroke/blood , von Willebrand Factor/metabolism , Aged , Antigens, CD/blood , Biomarkers/blood , Brain Ischemia/complications , Case-Control Studies , Female , Flow Cytometry , Humans , Ischemic Attack, Transient/drug therapy , Male , Middle Aged , Platelet Aggregation Inhibitors , Prospective Studies , Stroke/drug therapy , Stroke/etiologyABSTRACT
BACKGROUND: Maternal smoking is a key modifiable risk factor in preventing adverse pregnancy outcomes such as intrauterine growth restriction, preterm birth and stillbirth. AIM: This observational study examined annual trends of maternal smoking reported at the first prenatal visit in women who delivered in a large university maternity hospital for the 5 years 2011-2015. METHODS: We examined clinical and sociodemographic data computerised routinely for women who presented for prenatal care at the hospital between 2011 and 2015. Multinomial logistic regression was used to determine the maternal characteristics, health behaviours and psychiatric history associated with smoking behaviours. RESULTS: Of the 42,509 women the mean age was 31.4 ± 5.5 years, mean Body Mass Index (BMI) was 25.6 ± 5.1 kg/m2, and 39.5% were nulliparas. Overall, 52.6% reported they had never smoked, 34.9% were ex-smokers, 10.5% smoked ≤10 cigarettes per day, 1.9% smoked ≥11 cigarettes per day and 0.1% smoked e-cigarettes. Between 2011 and 2015 the prevalence of maternal cigarette smoking decreased from 14.3 to 10.9% (P < 0.001). Smoking during pregnancy was most strongly associated with younger age, multiparity, unemployment, unplanned pregnancy, a history of psychiatric problems, alcohol intake and illicit drug usage. CONCLUSIONS: The number of women who reported smoking at the first prenatal visit decreased annually. Amongst women who continue to smoke during pregnancy, there is a clustering of adverse lifestyle behaviour and psychological problems that may need to be addressed if smoking cessation interventions are going to succeed in improving fetal programming.
Subject(s)
Mothers , Prenatal Diagnosis/methods , Smoking/adverse effects , Adult , Female , Humans , Pregnancy , Prevalence , Risk Factors , Time FactorsABSTRACT
OBJECTIVE: Abnormal metabolic activities of chondrocytes may cause articular cartilage (AC) degradation, but key transcription factors regulating metabolic activities in AC of aging individuals remain unknown. This study aimed to investigate the role of transcription factor NFAT1 in regulating the expression of anabolic and catabolic molecules in AC of aged mice. METHODS: The hip, knee, and shoulder joints of BALB/c mice were harvested at 6, 12, 15, 18, and 24 months of age for histopathological and immunohistochemical (IHC) analyses. Total RNA was isolated from AC for gene expression. Genomic DNA and chromatin were prepared from AC for methylated DNA immunoprecipitation (MeDIP) and chromatin immunoprecipitation (ChIP) assays. RESULTS: NFAT1 expression in AC of mice was significantly decreased after 12 months of age, which was associated with reduced proteoglycan staining, decreased expression of chondrocyte markers, and increased expression of interleukin-1ß. Forced Nfat1 expression in chondrocytes from aged mice significantly reversed the abnormal metabolic activities. ChIP assays confirmed that NFAT1 bound to the promoter of the Acan, Col2a1, Col9a1, Col11a1, Il1b, Mmp13 and Tnfa genes in articular chondrocytes of aged mice. ChIP and MeDIP assays revealed that reduced NFAT1 expression in AC of aged mice was regulated by epigenetic histone methylation at the promoter region and was correlated with increased DNA methylation at introns 1 and 10 of the Nfat1 gene. CONCLUSION: NFAT1 is a transcriptional regulator of multiple anabolic and catabolic genes in AC of aged mice. Epigenetically mediated reduction of NFAT1 expression causes imbalanced metabolic activities of articular chondrocytes in aged mice.
Subject(s)
Chondrocytes , Animals , Cartilage, Articular , Cells, Cultured , DNA Methylation , Interleukin-1beta , Mice , NFATC Transcription Factors , ProteoglycansABSTRACT
The relative contribution of carbohydrate and fat oxidation to energy expenditure during exercise is dependent on variables including exercise intensity, mode, and recruited muscle mass. This study investigated patterns of substrate utilization during two non-weightbearing exercise modalities, namely cycling and rowing. Thirteen young, moderately trained males performed a continuous incremental (3-min stages) exercise test to exhaustion on separate occasions on an electronically braked cycle (CYC) ergometer and an air-braked rowing (ROW) ergometer, respectively. On two further occasions, participants performed a 20-min steady-state exercise bout at â¼50%VO2peak on the respective modalities. Despite similar oxygen consumption, rates of fat oxidation (FATox ) were â¼45% higher during ROW compared with CYC (P < 0.05) across a range of power output increments. The crossover point for substrate utilization occurred at a higher relative exercise intensity for ROW than CYC (57.8 ± 2.1 vs 42.1 ± 3.6%VO2peak , P < 0.05). During steady-state submaximal exercise, the higher FATox during ROW compared with CYC was maintained (P < 0.05), but absolute FATox were 42% (CYC) and 28% (ROW) lower than during incremental exercise. FATox is higher during ROW compared with CYC exercise across a range of exercise intensities matched for energy expenditure, and is likely as a consequence of larger muscle mass recruited during ROW.
Subject(s)
Exercise Test/instrumentation , Exercise/physiology , Lipid Metabolism/physiology , Physical Exertion/physiology , Breath Tests , Carbohydrate Metabolism/physiology , Heart Rate , Humans , Male , Oxidation-Reduction , Oxygen Consumption , Physical Endurance/physiology , Young AdultABSTRACT
INTRODUCTION: The importance of thrombin generation in the pathogenesis of TIA or stroke and its relationship with cerebral microembolic signals (MES) in asymptomatic and symptomatic carotid stenosis has not been comprehensively assessed. METHODS: Plasma thrombin generation parameters from patients with moderate or severe (≥ 50%) asymptomatic carotid stenosis were compared with those from patients with symptomatic carotid stenosis in the early (≤ 4 weeks) and late phases (≥ 3 months) after TIA or stroke in this prospective, pilot observational study. Thrombin generation profile was longitudinally assessed in symptomatic patients with data at each time point. Bilateral transcranial Doppler ultrasound monitoring of the middle cerebral arteries was performed whenever possible to classify patients as MES-positive or MES-negative. RESULTS: Data from 31 asymptomatic, 46 'early symptomatic' and 35 'late symptomatic' patients were analysed. Peak thrombin (344.2 nM vs 305.3 nM; p = 0.01) and endogenous thrombin potential (1772.4 vs 1589.7; p = 0.047) were higher in early symptomatic than asymptomatic patients. Peak thrombin production decreased in symptomatic patients followed up from the early to late phase after TIA or stroke (339.7 nM vs 308.6 nM; p = 0.02). Transcranial Doppler ultrasound data were available in 25 asymptomatic, 31 early symptomatic and 27 late symptomatic patients. Early symptomatic MES-positive patients had a shorter 'time-to-peak thrombin' than asymptomatic MES-positive patients (p=0.04), suggesting a more procoagulant state in this early symptomatic subgroup. DISCUSSION: Thrombin generation potential is greater in patients with recently symptomatic than asymptomatic carotid stenosis, and decreases over time following TIA or stroke associated with carotid stenosis. These data improve our understanding of the haemostatic/thrombotic biomarker profile in moderate-severe carotid stenosis.
Subject(s)
Carotid Stenosis/metabolism , Intracranial Embolism/metabolism , Thrombin/biosynthesis , Aged , Carotid Stenosis/drug therapy , Female , Humans , Intracranial Embolism/diagnostic imaging , Intracranial Embolism/drug therapy , Male , Middle Aged , Platelet Aggregation Inhibitors/therapeutic use , Risk Factors , Ultrasonography, Doppler, TranscranialABSTRACT
The impact of commencing or changing antiplatelet therapy on von Willebrand factor antigen (VWF:Ag) and von Willebrand factor propeptide (VWF:Ag II) levels has not been comprehensively assessed following TIA or ischaemic stroke. In this pilot, longitudinal, observational analytical study, VWF:Ag and VWF:Ag II levels were simultaneously quantified in platelet poor plasma by ELISA in patients within 4 weeks of TIA or ischaemic stroke (baseline), and then 14 days (14d) and >90 days (90d) after altering antiplatelet therapy. Ninety-one patients were recruited. Eighteen were initially assessed on no antiplatelet therapy, and then after 14d (N = 17) and 90d (N = 8) on aspirin monotherapy; 21 patients were assessed on aspirin and after 14d and 90d on clopidogrel; 52 were assessed on aspirin monotherapy, and after 14d and 90d on aspirin and dipyridamole combination therapy. VWF:Ag, VWF:Ag II levels and VWF:Ag/VWF:Ag II ratio were unchanged at 14d and 90d in the overall study population (p ≥ 0.1). VWF:Ag and VWF:Ag II levels remained stable at 14d and 90d after commencing aspirin (p ≥ 0.054), and after changing from aspirin to clopidogrel (p ≥ 0.2). Following the addition of dipyridamole MR to aspirin, there was a significant reduction in VWF:Ag levels at 14d (p = 0.03) and 90d (p = 0.005), but not in VWF:Ag II levels (p ≥ 0.3). The addition of dipyridamole to aspirin led to a persistent reduction in VWF:Ag but not in VWF:Ag II levels, suggesting that dipyridamole may inhibit release of platelet-derived VWF:Ag following TIA or ischaemic stroke.
Subject(s)
Ischemic Attack, Transient/blood , Ischemic Attack, Transient/drug therapy , Platelet Aggregation Inhibitors/therapeutic use , Protein Precursors/blood , Stroke/drug therapy , von Willebrand Factor/metabolism , Adult , Aged , Aspirin/therapeutic use , Clopidogrel , Dipyridamole/therapeutic use , Enzyme-Linked Immunosorbent Assay , Female , Humans , Longitudinal Studies , Male , Middle Aged , Pilot Projects , Statistics, Nonparametric , Stroke/metabolism , Ticlopidine/analogs & derivatives , Ticlopidine/therapeutic use , Time FactorsABSTRACT
BACKGROUND AND PURPOSE: von Willebrand factor propeptide (VWF:Ag II) is potentially a more sensitive marker of acute endothelial activation than von Willebrand factor antigen (VWF:Ag). These biomarkers have not been simultaneously assessed in asymptomatic versus symptomatic carotid stenosis patients. The relationship between endothelial activation and cerebral microembolic signals (MESs) detected on transcranial Doppler ultrasound is unknown. METHODS: In this multicentre observational analytical study, plasma VWF:Ag and VWF:Ag II levels in patients with ≥50% asymptomatic carotid stenosis were compared with those from patients with ≥50% symptomatic carotid stenosis in the 'early' (≤4 weeks) and 'late' (≥3 months) phases after transient ischaemic attack or ischaemic stroke. Endothelial activation was also longitudinally assessed in symptomatic patients during follow-up. Transcranial Doppler ultrasound monitoring classified patients as MES-positive or MES-negative. RESULTS: Data from 31 asymptomatic patients were compared with those from 46 early symptomatic and 35 late phase symptomatic carotid stenosis patients, 23 of whom had undergone carotid intervention. VWF:Ag II levels were higher in early (12.8 µg/ml; P < 0.001), late (10.6 µg/ml; P = 0.01) and late post-intervention (10.6 µg/ml; P = 0.038) symptomatic patients than asymptomatic patients (8.9 µg/ml). VWF:Ag levels decreased in symptomatic patients followed up from the early to late phase after symptom onset (P = 0.048). Early symptomatic MES-negative patients had higher VWF: Ag II levels (13.3 vs. 9.0 µg/ml; P < 0.001) than asymptomatic MES-negative patients. CONCLUSIONS: Endothelial activation is enhanced in symptomatic versus asymptomatic carotid stenosis patients, in early symptomatic versus asymptomatic MES-negative patients, and decreases over time in symptomatic patients. VWF:Ag II levels are a more sensitive marker of endothelial activation than VWF:Ag levels in carotid stenosis. The potential value of endothelial biomarkers and concurrent cerebral MES detection at predicting stroke risk in carotid stenosis warrants further study.
Subject(s)
Carotid Stenosis/blood , Endothelium/metabolism , Intracranial Embolism/blood , von Willebrand Factor , Aged , Biomarkers/blood , Brain Ischemia/etiology , Carotid Stenosis/complications , Carotid Stenosis/diagnostic imaging , Humans , Intracranial Embolism/diagnostic imaging , Ischemic Attack, Transient/etiology , Male , Middle Aged , Stroke/etiology , UltrasonographyABSTRACT
BACKGROUND/OBJECTIVES: Several factors affect the mental performance of children. The importance that parents attribute to food-related determinants, compared with genetic, socio-economic and school environment, was investigated. SUBJECTS/METHODS: Parents of school children (aged 4-11) were recruited through state primary schools in four European countries. Interviews were conducted in which participants were asked to sort 18 cards representing possible determinants of four elements of mental performance (attention, learning, mood and behaviour) according to perceived strength of effect. Determinants were identified from the literature and grouped in six categories: food-related, school environment, physical, social, psychological and biological. Effects were scored: 0=none; 1=moderate; and 2=strong. Views were compared between and within countries. RESULTS: Two hundred parents took part (England: 53; Germany: 45; Hungary: 52; Spain: 50). Differences existed between countries in the proportions reporting university education and being in employment. Taking all countries together, parents consider the food category (mean 1.33) to have a lower impact on a child's mental performance than physical (activity and sleep, 1.77), psychological (mood and behaviour, 1.69) and school environment (1.57). Social (1.12) and biological (0.91) determinants were ranked lower than food. Of determinants in the food category, parents thought regularity of meals had more influence on mental performance (1.58) than what a child eats now (1.36), food at school (1.35), nutrition as a baby/infant (1.02). CONCLUSION: Scope exists to improve parental awareness of the repercussions of their dietary choices for the mental performance of their children.
Subject(s)
Cognition/physiology , Diet , Feeding Behavior , Health Knowledge, Attitudes, Practice , Parents/psychology , Child , Child, Preschool , England , Female , Germany , Humans , Hungary , Male , Nutritional Status , Schools , Socioeconomic Factors , Spain , Surveys and QuestionnairesABSTRACT
BACKGROUND: Cerebral microembolic signals (MES) may predict increased stroke risk in carotid stenosis. However, the relationship between platelet counts or platelet activation status and MES in symptomatic vs. asymptomatic carotid stenosis has not been comprehensively assessed. SETTING: University teaching hospitals. METHODS: This prospective, pilot observational study assessed platelet counts and platelet activation status, and the relationship between platelet activation and MES in asymptomatic vs. early (≤ 4 weeks after TIA/stroke) and late phase (≥ 3 months) symptomatic moderate or severe (≥ 50%) carotid stenosis patients. Full blood count measurements were performed, and whole blood flow cytometry was used to quantify platelet surface activation marker expression (CD62P and CD63) and circulating leucocyte-platelet complexes. Bilateral simultaneous transcranial Doppler ultrasound monitoring of the middle cerebral arteries was performed for 1 h to classify patients as MES positive or MES negative. RESULTS: Data from 31 asymptomatic patients were compared with 46 symptomatic patients in the early phase, and 35 of these patients were followed up to the late phase after symptom onset. The median platelet count (211 vs. 200 × 10(9) L(-1) ; P = 0.03) and the median percentage of lymphocyte-platelet complexes was higher in early symptomatic than asymptomatic patients (2.8 vs. 2.4%; P = 0.001). The percentage of lymphocyte-platelet complexes was higher in early symptomatic than in asymptomatic patients with ≥ 70% carotid stenosis (P = 0.0005) and symptomatic patients recruited within 7 days of symptom onset (P = 0.028). Complete TCD data were available in 25 asymptomatic, 31 early phase symptomatic and 27 late phase symptomatic patients. Twelve per cent of asymptomatic vs. 32% of early phase symptomatic (P = 0.02) and 19% of late phase symptomatic patients (P = 0.2) were MES positive. Early symptomatic MES-negative patients had a higher percentage of lymphocyte-platelet complexes than asymptomatic MES-negative patients (2.8 vs. 2.3%; P = 0.0085). DISCUSSION: Recently, symptomatic carotid stenosis patients have had higher platelet counts (potentially reflecting increased platelet production, mobilization or reduced clearance) and platelet activation status than asymptomatic patients. MES were more frequently detected in early symptomatic than asymptomatic patients, but the differences between late symptomatic and asymptomatic groups were not significant. Increased lymphocyte-platelet complex formation in recently symptomatic vs. asymptomatic MES-negative patients indicates enhanced platelet activation in this early symptomatic subgroup. Platelet biomarkers, in combination with TCD, have the potential to aid risk-stratification in asymptomatic and symptomatic carotid stenosis patients.
Subject(s)
Carotid Stenosis/blood , Intracranial Embolism/blood , Platelet Activation , Aged , Asymptomatic Diseases , Biomarkers/blood , Carotid Stenosis/complications , Carotid Stenosis/immunology , Chi-Square Distribution , Female , Flow Cytometry , Hospitals, Teaching , Humans , Intracranial Embolism/diagnostic imaging , Intracranial Embolism/immunology , Ischemic Attack, Transient/blood , Ischemic Attack, Transient/immunology , Linear Models , Lymphocytes/immunology , Male , Middle Aged , P-Selectin/blood , Pilot Projects , Platelet Count , Predictive Value of Tests , Prospective Studies , Risk Factors , Severity of Illness Index , Stroke/blood , Stroke/etiology , Tetraspanin 30/blood , Time Factors , Ultrasonography, Doppler, Color , Ultrasonography, Doppler, TranscranialABSTRACT
BACKGROUND: There is now little doubt that improving antimicrobial use is necessary for the containment of resistance. OBJECTIVE: To determine whether providing individualised feedback to doctors about their recent compliance with the hospital's antibiotic policy improves compliance with the policy. METHODS: This study was conducted at a teaching hospital in Sydney, Australia. Computerised alerts integrated into the electronic prescribing system (ePS) inform prescribers of the local antibiotic policy. We utilised prescribing data extracted from the ePS for 'audit and feedback'. Thirty-six prescribers were sent feedback letters via email. We also interviewed doctors who had received letters to explore their views of the feedback and the policy in general. RESULTS: There was no significant change in compliance with the policy following implementation of the feedback intervention (0% compliant vs 11.9%; p = 0.07). Several problems with the policy and the approval process were identified by researchers during auditing and by prescribers during interviews. Some problems identified made it difficult to accurately assess compliance and for doctors to comply with the policy. CONCLUSION: Our intervention did not result in improved compliance with the antibiotic policy but revealed practical problems with the policy and approval process that had not been identified prior to the trial. Greater support for the policy by senior doctors and the assignment of more clearly defined roles and responsibilities associated with antibiotic use and approval may result in improved compliance. Harnessing the full potential of technology would streamline the antimicrobial approval process and allow more efficient and reliable monitoring of antibiotic use and compliance. Many of the problems we identified are generic issues of importance to all organisations seeking to integrate antimicrobial stewardship into ePS.