Cardiometabolic risk reduction in an intensive cardiovascular health program.

BACKGROUND AND AIMS: Insulin and leptin are important markers of insulin resistance and vascular inflammation in metabolic and cardiovascular diseases. This study evaluated changes in circulating levels of insulin and leptin during a cardiovascular health program to improve our understanding of cardiometabolic risk reduction. METHODS AND RESULTS: Participants (n=76) completed a prospective, nonrandomized program designed to stabilize or reverse progression of coronary artery disease through dietary changes, exercise, stress management, and group support. Controls (n=76) were matched to participants based on age, gender, and disease status. Traditional cardiovascular risk factors were assessed at baseline, 12 weeks, and 52 weeks by standard methods. Dietary data were collected by 72-h recall and evaluated by Food Processor® v8.4.0. Ultrasensitive insulin and leptin levels were measured by radioimmunoassay. Participants successfully reduced their total caloric intake from >2000 calories per day to ≈ 1700 calories per day (p<0.05 compared to controls), lowered daily fat intake by >60% (p<0.001 compared to controls), and increased carbohydrate intake by >30% (p<0.001). Repeated-measures ANOVA indicated significant beneficial changes (p<0.001 compared to controls) in plasma insulin (-19%) and leptin (-33%) during the lifestyle program, as well as improvement in traditional cardiovascular risk factors. Response was similar between men and women for most risk factors and was not markedly influenced by medication use. CONCLUSION: Lifestyle changes focusing on diet, physical activity, and stress reduction can successfully modify both cardiovascular and metabolic risk factors, with the potential to mediate cardiometabolic risk through beneficial anti-inflammatory and anti-oxidative effects on the vasculature.

Direct determination of carbon dioxide in aqueous solution using mid-infrared quantum cascade lasers.

A method for the direct determination of carbon dioxide in aqueous solutions using a room-temperature mid-infrared (MIR) quantum cascade laser at 2330 cm(-1) is reported. The absorption values of different carbon dioxide concentrations were measured in a 119 microm CaF2 flow-through cell. An optical system made of parabolic mirrors was used to probe the flow cell and to focus the laser beam on the mercury cadmium telluride (MCT) detector. Aqueous carbon dioxide standards were prepared by feeding different mixtures of gaseous N2 and CO2 through wash bottles at controlled temperature. The concentration of the dissolved CO2 was calculated according to Henry's law, taking into account the temperature and the partial pressure of CO2. The carbon dioxide standards were connected via a selection valve to a peristaltic pump for subsequent, automated measurement in the flow-through cell. A calibration curve was obtained in the range of 0.338 to 1.350 g/L CO2 with a standard deviation of the method sxo equal to 19.4 mg/L CO2. The limit of detection was calculated as three times the baseline noise over time and was determined to be 39 mg/L.

A mid-IR flow-through sensor for direct monitoring of enzyme catalysed reactions. Case study: Measurement of carbohydrates in beer.

A novel mid-IR flow-through sensor for in situ monitoring of the enzymatic reaction of amyloglucosidase with carbohydrates was developed. Amyloglucosidase was immobilised on agarose beads with N-ethyl-N'-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) and directly placed in a conventional IR flow-through cell. The carbohydrate content of various beer samples was then determined by following the enzymatic hydrolytic cleavage of carbohydrates to glucose with Fourier-transform infrared (FTIR) spectroscopy. The whole procedure was done in an automated way operating in the stopped flow mode by incorporating the flow-through sensor in a sequential injection (SI) manifold. As the immobilised enzyme was directly probed by the IR beam, an in situ study of the enzymatic reaction was possible enabling determination of the Michaelis-Menten constant of the immobilised enzyme. A linear calibration curve was recorded using maltose standards in the range between 0.86 and 7.13 g L(-1). The proposed method was successfully applied to the determination of the carbohydrate content of four different beer samples by the standard addition method. Moreover experiments showed the possibility of monitoring in situ the immobilisation of the enzyme as well as a small organic acid (malic acid) on the agarose beads using EDC.

Comparison of different lymphoma cell purging modalities: An experimental study with K422 lymphoma cells.

Blood-derived autografts from patients with non-Hodgkin's lymphoma (NHL) are frequently contaminated with clonogenic lymphoma cells. In order to obtain a more efficient lymphoma cell depletion from the transplants we compared the efficiency of different purging techniques: B-cell-directed depletion, CD34+ selection by immunomagnetic beads (IMB selection) or by immunoadsorption with a biotin-avidin column (BAC selection). Furthermore, two combination approaches were investigated: IMB selection after B-cell depletion as well as BAC selection after B-cell depletion. To assess purging efficiency, fluorescence-tagged (PKH26) K422 follicular NHL cells were admixed to the respective samples of leukapheresis products. BAC selection following B-cell depletion compared to BAC selection alone showed no significant differences in CD34+ purity (77 +/- 12. 5% vs. 70.7 +/- 5.4%) (mean +/- SE) or CD34+ recovery (35.3 +/- 8.5% vs. 32.8 +/- 10.4%), but a significantly (p < 0.005) higher lymphoma cell purging efficiency (log 4.32 +/- 0.15 vs. log 2.92 +/- 0.19). IMB selection following B-cell depletion and IMB selection alone resulted in a CD34+ purity of 40.8 +/- 8.7% and 64.7 +/- 7.9%, a CD34+ recovery of 47.2 +/- 8.3% and 26.5 +/- 6.5% and a lymphoma cell purging efficiency of log 3.68 +/- 0.16 and log 3.48 +/- 0.21, respectively. Lymphoma cell purging efficiency after either CD34 selection method alone as well as after either double purging method was significantly higher (p < 0.0005 and p < 0.00005, respectively) compared to B-cell depletion alone (log 1.44 +/- 0.23). Our results argue for the combination of different purging modalities to achieve a maximal lymphoma cell depletion.