25 research outputs found
Impact of flavonoid-rich black tea and beetroot juice on postprandial peripheral vascular resistance and glucose homeostasis in obese, insulin-resistant men: a randomized controlled trial.
BACKGROUND: Insulin-stimulated muscle blood flow facilitates plasma glucose disposal after a meal, a mechanism that is impaired in obese, insulin-resistant volunteers. Nitrate- or flavonoid-rich products, through their proposed effects on nitric oxide, may improve postprandial blood flow and, subsequently, glucose disposal. To investigate whether a single dose of nitrate-rich beetroot juice or flavonoid-rich black tea lowers postprandial muscle vascular resistance in obese volunteers and alters postprandial glucose or insulin concentrations. METHOD: In a randomised, controlled, cross-over study, 16 obese, insulin-resistant males consumed 75Â g glucose, which was combined with 100Â ml black tea, beetroot juice or control (water). Peripheral vascular resistance (VR), calculated as mean arterial pressure divided by blood flow, was assessed in the arm and leg conduit arteries, resistance arteries and muscle microcirculation across 3Â h (every 30-min) after the oral glucose load. RESULTS: During control, we found no postprandial response in VR in conduit, resistance and microvessels (all Pâ>â0.05). Black tea decreased VR compared to control in conduit, resistance and microvessels (all Pâ<â0.05). Beetroot juice decreased postprandial VR in resistance vessels, but not in conduit artery and microvessels. Although postprandial glucose response was similar after all interventions, postprandial insulin response was attenuated by ~29Â % after tea (Pâ<â0.0005), but not beetroot juice. CONCLUSIONS: A single dose of black tea decreased peripheral VR across upper and lower limbs after a glucose load which was accompanied by a lower insulin response. Future studies in insulin-resistant subjects are warranted to confirm the observed effects and to explore whether long-term regular tea consumption affects glucose homeostasis. TRIAL REGISTRATION: The study was registered at clinicaltrials.gov on 30(th) November 2012 (NCT01746329)
The effect of consuming instant black tea on postprandial plasma glucose and insulin concentrations in healthy humans.
Exploring the definition of «acute» neck pain: a prospective cohort observational study comparing the outcomes of chiropractic patients with 0-2 weeks, 2-4 weeks and 4-12 weeks of symptoms
Abstract Background Neck pain is a common complaint in chiropractic patients. Amongst other baseline variables, numerous studies identify duration of symptoms as a strong predictor of outcome in neck pain patients. The usual time frame used for âacuteâ onset of pain is between 0 and 4 weeks. However, the appropriateness of this time frame has been challenged for chiropractic low back pain patients. Therefore, the purpose of this study was to compare outcomes in neck pain patients with 0â2 vs 2â4 and 4â12 weeks of symptoms undergoing chiropractic treatment. Methods This is a prospective cohort observational study with 1 year follow-up including 495 patients whose data was collected between October 2009 and March 2015. Patients were divided into high-acute (0â2 weeks), mid-acute (2â4 weeks) and subacute (4â12 weeks) corresponding to duration of their symptoms at initial treatment. Patients completed the numerical pain rating scale (NRS) and Bournemouth questionnaire for neck pain (BQN) at baseline. At follow-up time points of 1 week, 1 month, 3 months, 6 months and 1 year the NRS and BQN were completed along with the Patient Global Impression of Change (PGIC) scale. The PGIC responses were dichotomized into âimprovedâ and ânot improvedâ patients and compared between the 3 subgroups. The Chi-square test was used to compare improved patients between the 3 subgroups and the unpaired Studentâs t-test was used for the NRS and BQN change scores. Results The proportion of patients âimprovedâ was only significantly higher for patients with symptoms of 0â2 weeks compared to 2â4 weeks at the 1 week outcome time point (p = 0.015). The NRS changes scores were significantly greater for patients with 2â4 weeks of symptoms compared to 4â12 weeks of symptoms only at 1 week (p = 0.035). Conclusions The time period of 0â4 weeks of symptoms as the definition of âacuteâ neck pain should be maintained. Independent of the exact duration of symptoms, medium-term and long-term outcome is favourable for acute as well as subacute neck pain patients. Trial registration Not applicable for prospective cohort studies. Ethics approval prior to study EK 19/2009
Validation of an improved competitive enzyme-linked immunosorbent assay to detect Equine arteritis virus
The objective of the present study was to validate a previously described competitive enzyme-linked immunosorbent assay (cELISA) to detect antibody to Equine arteritis virus (EAV) based on GP5-specific nonneutralizing monoclonal antibody (mAb) 17B79 using the World Organization for Animal Health (OIE)ârecommended protocol, which includes the following 5 in-house analyses. 1) The assay was calibrated with the OIE-designated reference serum panel for EAV; 2) repeatability was evaluated within and between assay runs; 3) analytical specificity was evaluated using sera specific to related viruses; 4) analytical sensitivity was evaluated with sera from horses vaccinated with an EAV modified live virus (MLV) vaccine; and 5) the duration of cELISA antibody detection following EAV vaccination was determined. The positive cELISA cutoff of â„35% inhibition (%I) was confirmed by receiver operating characteristic plot analysis. Analytical sensitivity of the cELISA was comparable to the serum neutralization (SN) assay in that it detected EAV-specific antibody as early as 8 days postvaccination. The duration of EAV-specific antibody detected by cELISA was over 5 years after the last vaccination. This cELISA could detect EAV-specific antibody in serum samples collected from horses infected with various EAV strains. In the field trial performed by American Association of Veterinary Laboratory Diagnosticiansâaccredited state laboratories and OIE laboratory, the diagnostic specificity of the cELISA was 99.5% and the diagnostic sensitivity was 98.2%. The data using various serum panels also had consistently significant positive correlation between SN titers and cELISA %I results. The results further confirm that the EAV antibody cELISA is a reliable, simple alternative to the SN assay for detecting EAV-specific antibodies in equine sera