Adipokines and Inflammatory Markers in Acute Myocardial Infarction Patients with and without Obstructive Sleep Apnea: A Comparative Analysis.

An association has been suggested between acute myocardial infarction (AMI) and obstructive sleep apnea (OSA). Considering the role of adipose-tissue-derived inflammatory mediators (adipokines) and the shared risk factor of obesity in OSA and AMI, this study aimed to investigate the involvement of adipokines in AMI patients with and without OSA. Serum levels of adipokines and inflammatory mediators were quantified, and home respiratory polygraphy was conducted. A total of 30 AMI patients and 25 controls were included. Patients with AMI exhibited elevated levels of resistin (7.4 vs. 3.7 ng/mL), interleukin-6 (8.8 vs. 1.3 pg/mL), and endothelin-1 (3.31 vs. 1.8 pg/mL). Remarkably, AMI patients with concomitant OSA exhibited higher levels of resistin (7.1 vs. 3.7 ng/mL), interleukin-6 (8.9 vs. 1.3 pg/mL), endothelin-1 (3.2 vs. 1.8 pg/mL), creatin kinase (1430 vs. 377 U/L), creatine kinase-MB (64.6 vs. 9.7 ng/mL), and troponin T (2298 vs. 356 pg/mL) than their non-OSA counterparts. Leptin showed a correlation with OSA severity markers. OSA was associated with greater cardiac damage in AMI patients. Our findings underscore that adipokines alone are not sufficient to discriminate the risk of AMI in the presence of OSA. Further research is necessary to determine the potential mechanisms contributing to exacerbated cardiac damage in patients with both conditions.

Correlation of the DNA Concentration of Human Samples to Electrical Bioimpedance Measurements: A Pilot Study.

It is necessary to evaluate the total deoxyribonucleic acid (DNA) concentration in gene expression assays. The existing techniques require equipment that is expensive for many labs in developing countries. Portable and inexpensive equipment is needed for easy and economical DNA quantification. Electrical bioimpedance spectroscopy (EBiS) is a non-invasive and inexpensive technique for examining the electrical properties of biological materials. The aim of this study was to explore a potential correlation between the measurement of total DNA extracted from human samples by UV-Vis spectrophotometry and EBiS. Hence, after quantifying the total DNA extracted from each sample by UV-Vis spectroscopy, EBiS was recorded and a possible correlation between the two measurements was analyzed. Considering the bioimpedance phase parameter at 5.24 MHz, a significant correlation was found with total DNA, especially when the concentration was below 100 ng/µL (Spearman coefficient = 0.82, p<0.005). Additional experiments are warranted to confirm these findings.

Sensitivity analysis of electrical bioimpedance patterns of breast cancer cells labeled with magnetic nanoparticles: forming the foundation for a biosensor of circulating tumor cells.

OBJECTIVE: To determine the sensitivity of electrical impedance spectroscopy (EIS) measurements for the detection of a small concentration of breast cancer cells in suspension, previously labeled with magnetic nanoparticles (MNPs) and separated. Additionally, the relation of electrical impedance to the expression of molecular markers was established. APPROACH: MCF-7, MDA-MB-231 and SK-BR-3 breast cancer cell lines at different concentrations (50, 500 and 5000 cells/500 µl) were labeled with a magnetic nanoparticle-antibody (MNP-ab) bioconjugate that recognizes the corresponding molecular markers (EpCAM, MUC-1 and HER-2, respectively). Electrical bioimpedance spectra (100 Hz to 1 MHz) were recorded in each case. MAIN RESULTS: At the frequency centered at 100 KHz, EIS displayed a greater sensitivity for magnitude when using 50 cells/500 µl (4.11 ± 0.23, 8.81 ± 1.73 and 17.5 ± 3.61 ohms for MCF-7, MDA-MB-231 and SK-BR-3, respectively). There were no significant differences between the phases of impedance tested at the greatest sensitivity of 1 KHz (-78.05 ± 0.53, -79.23 ± 0.93 and -75.26 ± 0.72 degrees for MCF-7, MDA-MB-231 and SK-BR-3, respectively). SIGNIFICANCE: Under the present conditions, EIS was sensitive enough to detect a low concentration of breast cancer cells (50 cells/500 µl) and classify the distinct cells lines with a signature impedance pattern, as long as the MNP concentration was very low (⩽0.125 mg MNPs/50 000 cells). The relative expression of the molecular markers on each cancer cell line was related to the magnitude of the electrical impedance.