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Phytosterols are natural components of plant-based foods used as supplements because of their known cholesterol-lowering effect. However, their effects on lipoprotein subfractions and the quality of the LDL particle have not been studied in greater detail. We aimed to evaluate the effects of phytosterols supplements on lipids, lipoproteins subfractions, and on the quality of LDL. A prospective, pilot-type, open label, cross-over study, randomized 23 males in primary prevention of hypercholesterolemia to receive diet or diet plus phytosterol (2.6 g in 2 doses, with meals) for 12 weeks, when treatments were switched for another 12 weeks. Lipoprotein subfractions were analyzed by electrophoresis in polyacrylamide gel (Lipoprint System®). The Sampson equation estimated the small and dense (sd) and large and buoyant (lb) LDL subfractions from the lipid profile. Quality of LDL particle was analyzed by Z-scan and UV-vis spectroscopy. Primary outcome was the comparison of diet vs. diet plus phytosterols. Secondary outcomes assessed differences between baseline, diet and diet plus phytosterol. Non-parametric statistics were performed with p < 0.05. There was a trend to reduction on HDL-7 (p = 0.05) in diet plus phytosterol arm, with no effects on the quality of LDL particles. Heatmap showed strong correlations (ρ > 0.7) between particle size by different methods with both interventions. Diet plus phytosterol reduced TC, increased HDL-c, and reduced IDL-B, whereas diet increased HDL7, and reduced IDL-B vs. baseline (p < 0.05, for all). Phytosterol supplementation demonstrated small beneficial effects on HDL-7 subfraction, compared with diet alone, without effects on the quality of LDL particles.This trial is registered in Clinical Trials (NCT06127732) and can be accessed at https://clinicaltrials.gov ., (© 2024. The Author(s).)

In this study, we aimed to examine the impact of high endurance training on vascular health parameters and immune-endocrine responses against modified low-density lipoprotein (LDL) particles. This observational, cross-sectional study included high endurance-trained and healthy non-trained subjects. Vascular ultrasound was used to assess vascular health parameters based on carotid intima-media thickness and endothelial function (flow-mediated dilation). Enzyme-linked immunosorbent assays were used to measure interleukin (IL)-8 and IL-10, autoantibody isotypes anti-oxidized LDL (oxLDL) and anti-apolipoprotein B (ApoB-D) peptide. Plasma levels of the corticosterone and 17 α-hydroxyprogesterone hormones were analyzed by mass spectrometry. This study enrolled 96 subjects, of whom 44 were high endurance trained and 52 were healthy non-trained individuals. Smaller carotid intima-media thickness values were observed in the high-endurance trained than in the healthy non-trained males, while no differences were observed between female groups. Flow-mediated dilation measurements did not differ by training or sex. The humoral immune responses to IgG anti-oxLDL and IgM anti-ApoB-D autoantibodies showed an isotype imbalance between the high-endurance trained and the non-trained groups. Immunoendocrine parameters showed inverse correlations between 17 α-hydroxyprogesterone concentrations and carotid intima-media thickness measurements. Direct correlations were found between IL-10 concentrations and flow-mediated dilation measurements. Chronic high-endurance exercise modulates immune-endocrine and vascular health parameters, in a sex-dependent manner., Competing Interests: The authors declare no conflict of interest., (Thieme. All rights reserved.)

We investigate the nonlinear behavior of the electric impedance of a kerosene-based ferrofluid (FF) sample subjected to an ac electric voltage of amplitude ranging from 10 mV to 3 V in the frequency range 6.3 mHz, 100 kHz. The FF sample was inserted between two parallel gold electrodes separated by 127 μm distance. The results show that even a sinusoidal voltage of amplitude low as 80 mV can give origin to nonlinear effects for frequency of the applied voltage smaller than 100 mHz. Our experimental data confirm the results obtained by solving numerically the equations of the Poisson-Nernst-Planck model. From this agreement it follows that the model based on the equation of continuity for the mobile ions, and the equation of Poisson for the actual potential across the sample, works well also in its non-linear version.

Background: Despite lipid-lowering and antiplatelet therapy, the pattern of residual lipoproteins seems relevant to long-term cardiovascular outcomes. This study aims to evaluate the effects of combined therapies, commonly used in subjects with acute myocardial infarction, in the quality of low-density lipoprotein (LDL) particles., Methods: Prospective, open-label trial, included patients with acute myocardial infarction. Patients were randomized to antiplatelet treatment (ticagrelor or clopidogrel) and subsequently to lipid-lowering therapy (rosuvastatin or simvastatin/ezetimibe) and were followed up for six months. Nonlinear optical properties of LDL samples were examined by Gaussian laser beam (Z-scan) to verify the oxidative state of these lipoproteins, small angle X-ray scattering (SAXS) to analyze structural changes on these particles, dynamic light scattering (DLS) to estimate the particle size distribution, ultra violet (UV)-visible spectroscopy to evaluate the absorbance at wavelength 484 nm (typical from carotenoids), and polyacrylamide gel electrophoresis (Lipoprint) to analyze the LDL subfractions., Results: Simvastatin/ezetimibe with either clopidogrel or ticagrelor was associated with less oxidized LDL, and simvastatin/ezetimibe with ticagrelor to lower cholesterol content in the atherogenic subfractions of LDL, while rosuvastatin with ticagrelor was the only combination associated with increase in LDL size., Conclusions: The quality of LDL particles was influenced by the antiplatelet/lipid-lowering strategy, with ticagrelor being associated with the best performance with both lipid-lowering therapies. Trial registration: NCT02428374., Competing Interests: I confirm that this does not alter our adherence to PLOS ONE policies on sharing data and materials. The study design, data collection, statistical analysis, or publications were not influenced by the sponsors and are the exclusive responsibility of the investigators.

We show that the electric response of a cell in the shape of a slab containing a ferrofluid (magnetic particles in kerosene) can be interpreted by means of a model based on the adsorption of ions from limiting surfaces. We report on three samples, identical in all aspects, but limited by electrodes in gold, platinum and titanium. For frequency larger than 1 kHz, the spectra of the real and imaginary parts of the total electrical impedance of the cells are identical. From this result it follows that in this frequency range the response of the cell is independent of the electrodes, which can be considered as blocking. In the low frequency region, up to 0.3 mHz, the response of the cells depends on the electrodes, as discussed recently by Batalioto et al. , Phys. Chem. Chem. Phys. , 2021, 23 , 2819. A simple generalization of the PNP model with ohmic boundary conditions works well only up to 10 mHz. For frequencies smaller than this value the reactance of the cells tends to increase again, indicating a capacity behaviour that could be related to the adsorption effect of the electrodes. A generalization of the ohmic PNP model containing surface capacitance in series is able to fit the data. From the value of the surface capacitance, the thickness of the surface layer is estimated to be on the molecular scale. From this result, we conclude that the adsorption phenomenon could be important for the description of the electrical properties of these systems. A simple generalization of the PNP model with boundary conditions derived by the Langmuir model is in reasonable agreement with our experimental data. The analysis is performed at the impedance level, taking into account a test based on the tangent of the loss angle of the system.

Background: Large observational studies have shown that small, dense LDL subfractions are related to atherosclerotic cardiovascular disease. This study assessed the effects of two highly effective lipid-lowering therapies in the atherogenic subclasses of lipoproteins in subjects with ST-segment elevation myocardial infarction (STEMI)., Methods: Patients of both sexes admitted with their first myocardial infarction and submitted to pharmacoinvasive strategy (N = 101) were included and randomized using a central computerized system to receive a daily dose of simvastatin 40 mg plus ezetimibe 10 mg or rosuvastatin 20 mg for 30 days. Intermediate-density lipoprotein (IDL) and low-density lipoprotein (LDL) subfractions were analysed by polyacrylamide gel electrophoresis (Lipoprint System) on the first (D1) and 30th days (D30) of lipid-lowering therapy. Changes in LDL and IDL subfractions between D1 and D30 were compared between the lipid-lowering therapies (Mann-Whitney U test)., Results: The classic lipid profile was similar in both therapy arms at D1 and D30. At D30, the achievement of lipid goals was comparable between lipid-lowering therapies. Cholesterol content in atherogenic subclasses of LDL (p = 0.043) and IDL (p = 0.047) decreased more efficiently with simvastatin plus ezetimibe than with rosuvastatin., Conclusions: Lipid-lowering therapy with simvastatin plus ezetimibe was associated with a better pattern of lipoprotein subfractions than rosuvastatin monotherapy. This finding was noted despite similar effects in the classic lipid profile and may contribute to residual cardiovascular risk., Trial Registration: ClinicalTrials.gov , NCT02428374, registered on 28/09/2014., (© 2021. The Author(s).)

For cardiovascular disease prevention, statins alone or combined with ezetimibe have been recommended to achieve low-density lipoprotein cholesterol targets, but their effects on other lipids are less reported. This study was designed to examine lipid changes in subjects with ST-segment elevation myocardial infarction (STEMI) after two highly effective lipid-lowering therapies. Twenty patients with STEMI were randomized to be treated with rosuvastatin 20 mg QD or simvastatin 40 mg combined with ezetimibe 10 mg QD for 30 days. Fasting blood samples were collected on the first day (D1) and after 30 days (D30). Lipidomic analysis was performed using the Lipidyzer platform. Similar classic lipid profile was obtained in both groups of lipid-lowering therapies. However, differences with the lipidomic analysis were observed between D30 and D1 for most of the analyzed classes. Differences were noted with lipid-lowering therapies for lipids such as FA, LPC, PC, PE, CE, Cer, and SM, notably in patients treated with rosuvastatin. Correlation studies between classic lipid profiles and lipidomic results showed different information. These findings seem relevant, due to the involvement of these lipid classes in crucial mechanisms of atherosclerosis, and may account for residual cardiovascular risk.Randomized clinical trial: ClinicalTrials.gov, NCT02428374, registered on 28/09/2014., (© 2021. The Author(s).)

The aim of this study was to investigate the effects of 6-months consumption of green-banana biomass on the LDL particle functionality in subjects with type 2 diabetes. Subjects (n = 39, mean age 65 years old) of both sexes with diabetes (HbA1c ≥ 6·5%) were randomized to receive nutritional support plus green-banana biomass (40 g) (n = 21) or diet alone (n = 18) for 6-months. Non-linear optical responses of LDL solutions from these participants were studied by Z-scan technique. UV-visible spectrophotometer was used to measure the absorbance of the LDL samples. Small Angle X-ray Scattering and Dynamic Light Scattering experiments were used to look for any structural changes in LDL samples and to determine their size distribution. The Lipoprint test was used to determine the LDL sub-fractions in terms of distribution and size. Consumption of green-banana biomass, reduced total- (p = 0.010), non-HDL-cholesterol (p = 0.043), glucose (p = 0.028) and HbA1c (p = 0.0007), and also improved the protection of the LDL particle against oxidation, by the increase in carotenoids content in the particles (p = 0.007). This higher protection against modifications may decrease the risk of developing cardiovascular disease. These benefits of the green-banana biomass encourage the use of resistant starches with potential clinical applications in individuals with pre-diabetes and diabetes.

Some ionic surfactant-based lyotropic mixtures, exhibiting cholesteric phases, were prepared to investigate the effect of the surfactant alkyl chain length on a) uniaxial-to-biaxial phase transitions and b) stabilization of different cholesteric phases. Potassium alkanoates, KCx, (potassium undecanoate, KC11, potassium dodecanoate, KC12, and potassium tridecanoate, KC13) were chosen as the surfactant molecules. The lyotropic mixtures, which were composed of KCx/potassium sulfate (K 2 SO 4 )/decanol (DeOH)/water/brucine, where brucine is a chiral dopant molecule, were studied. Partial phase diagrams were constructed to show how the surfactant alkyl chain affects the phase topologies in the phase diagrams. It was observed that the presence of a longer surfactant alkyl chain in the mixture favors the stabilization of the larger discotic cholesteric, Ch D , and cholesteric biaxial, Ch B , phase domains. The phase transitions from the uniaxial cholesteric to biaxial cholesteric phase were shifted to lower temperatures.

Lyotropic quaternary mixtures of some tetradecylalkylammonium bromide surfactants were prepared to examine the effect of the size of the surfactant head group on the stabilization of different lyotropic nematic phases. The lyotropic mixtures were prepared by the addition of the tetradecylalkylammonium bromides (TTAABr) in the mixture of NaBr/decanol (DeOH)/water. The uniaxial to biaxial nematic phase transitions were determined via laser conoscopy. Some micellization parameters such as critical micelle concentration, degree of counterion binding and micellization Gibbs energy were evaluated from the electrical conductivity measurements of diluted binary surfactants/water solutions. The results indicate that the head-group size of the surfactant molecules influences the amphiphilic molecular aggregate topology. Moreover, the effective area per surfactant head group is a key parameter on stabilizing the lyotropic biaxial nematic phase.

Amino acid-based surfactants were used as the main surfactants to prepare new lyotropic mixtures presenting three nematic phases. One of them is biaxial ( N B ), and the two others are uniaxial, discotic ( N D ) and calamitic ( N C ). These surfactants were the non-chiral molecules, potassium N -dodecanoyl-DL-alaninate (DL-KDDA), potassium N -dodecanoyl-DL-serinate (DL-KDDS), disodium N - dodecanoyl-DL-aspartate (DL-NaDDAs) and potassium N -dodecanoyl-glycinate (KDDGly). Measurements of the optical birefringences and X-ray diffraction analysis were used to characterize the nematic phases and phase transitions. Mixtures with DL-KDDS exhibited the largest biaxial phase domain (~9 °C) with respect to the other mixtures in this study. The results obtained with the KDDGly mixture showed that the existence of hydrogen bonding between the head groups of the surfactant molecules seems to hinder the orientation of the micelles under the action of an external magnetic field.