Aerobic Training in Young Men Increases the Transfer of Cholesterol to High Density Lipoprotein In Vitro: Impact of High Density Lipoprotein Size

Exercise training not only improves the plasma lipid profile but also reduces risk of developing coronary heart disease. We investigate whether plasma lipids and high density lipoprotein (HDL) metabolism are affected by aerobic training and whether the high-density lipoprotein cholesterol (HDL-C) levels at baseline influence exercise-induced changes in HDL. Seventy-one male sedentary volunteers were evaluated and allocated in two subgroups, according to the HLD-C levels (< or >40 mg/dL). Participants underwent an 18-week aerobic training period. Blood was sampled before and after training for biochemical analysis. Plasma lipids, apolipoproteins, HDL diameter, and VO₂ peak were determined. Lipid transfers to HDL were determined in vitro by incubating plasma samples with a donor lipid artificial nanoemulsion. After the 18-week period of aerobic training, the VO₂ peak increased, while the mean body mass index (BMI) decreased. HDL-C concentration was higher after the training period, but low-density lipoprotein cholesterol (LDL-C) and non-HDL-C did not change. The transfer of esterified cholesterol and phospholipids was greater after exercise training, but the triacylglycerol and unesterified cholesterol transfers were unchanged. The HDL particle diameter increased after aerobic training in all participants. When the participants were separated in low-HDL and normal-HDL groups, the postaerobic exercise increment in HDL-C was higher in the low-HDL group, while the transfer of esterified cholesterol was lower. In conclusion, aerobic exercise training increases the lipid transfers to HDL, as measured by an in vitro method, which possibly contributes to the classical elevation of the HDL-C associated with training.     

Engineering Biofunctional Enzyme-Mimics for Catalytic Therapeutics and Diagnostics

The applications of nanomaterial-based enzyme-mimics (Enz-Ms) in biocatalytically therapeutic and diagnostic fields have attracted extensive attention. The regulation of the biocatalytic performances and biofunctionalities of Enz-Ms are essential research objectives, including the rational design and synthesis of Enz-Ms with desired biofunctional molecules and nanostructures, especially at the level of molecules and even single atoms. Here, this timely progress report provides pivotal advances and comments on recent researches on engineering biofunctional Enz-Ms (BF/Enz-Ms), particularly chemical synthesis, functionalization strategies, and integration of diverse enzyme-mimetic catalytic activities of BF/Enz-Ms. First, the definitions and catalogs of BF/Enz-Ms are briefly introduced. Then, detailed comments and discussions are provided on the fabrication protocols, biocatalytic properties, and therapeutic/diagnostic applications of engineered BF/Enz-Ms via hydrogels, nanogels, metal–organic frameworks, metal–polyphenol networks, covalent–organic frameworks, functional cell membranes, bioactive molecules and polymers, and composites. Finally, the future perspectives and challenges on BF/Enz-Ms are outlined and thoroughly discussed. It is believed that this progress report will give a chemical and material overview on the state-of-the-art designing principles of BF/Enz-Ms, thus further promoting their future developments and prosperities for a wide range of applications.     

The Expression of Lipoprotein Receptors Is Increased in the Infarcted Area After Myocardial Infarction Induced in Rats With Cardiac Dysfunction

Left ventricular (LV) remodeling after myocardial infarction constitutes the structural basis for ventricular dysfunction and heart failure. The characterization underlying the expression of lipoprotein receptors in cardiac dysfunction is scarcely explored. The aim of this study was to analyze the status of lipoprotein receptors on the infarcted and noninfarcted areas of LV and to verify whether nanoparticles that mimic the lipid structure of low‐density lipoprotein (LDL) and have the ability to bind to LDL receptors (LDE) are taken up more avidly by the noninfarcted LV. 13 male Wistar rats with left coronary artery ligation (myocardial infarction [MI]) and 12 animals with SHAM operation (SHAM) were used in this study. 6 weeks after the procedure, the quantification of low‐density lipoprotein receptor (LDLR), LDL receptor‐related protein 1 (LRP1), scavenger receptor‐class B type I (SR‐BI) lipoprotein receptors, and PCNA proliferation marker, and tissue uptake of radioactively labeled LDE were performed. Immunohistochemistry and Western blot analysis showed that LDLR, LRP1, SR‐BI, and PCNA, expression in infarcted area of MI was remarkably higher than SHAM and noninfarcted subendocardial (SEN) and interstitial (INT) areas. In addition, in SEN noninfarcted area of MI, the presence of LDLR was about threefold higher than in SHAM SEN and INT noninfarcted areas. The LDE uptake of noninfarcted LV of MI group was about 30% greater than that of SHAM group. In conclusion, these findings regarding the status of lipoprotein receptors after MI induction could help to establish mechanisms on myocardial repairing. In conclusion, infarcted rats with LV dysfunction showed increased expression of lipoprotein receptors mainly in the infarcted area.     

Antimicrobial multiresistance in bacteria isolated from freshwater Chilean salmon farms

The intensive use of antimicrobial agents, mainly oxytetracycline, to prevent and control bacterial pathologies in Chilean salmon culture is a frequent practice. A total of 103 gram-negative oxytetracycline-resistant bacteria recovered from various sources of 4 Chilean freshwater salmon farms were identified and investigated for their susceptibility patterns to various antibacterial agents, by using an agar disk diffusion method. Antibacterial resistance patterns of isolates were not correlated with bacterial species or strain source. A high number of bacteria resistant to amoxicillin, ampicillin. erythromycin, and furazolidone, as well as an important frequency of bacterial resistance to florfenicol, chloramphenicol, cefotaxime and trimethoprim-sulfamethoxazole was found. On the contrary, the proportion of bacteria resistant to gentamicin, kanamycin, flumequine and enrofloxacin was rather low. Resistant microflora showed a high taxonomic variability and mainly consisted of non-fermenting bacteria (77.7%). These strains mainly belonged to the species Pseudomonas fluorescens (29), Aeromonas hydrophila (10), Stenotrophomonas maltophilia (6), isolated from salmon fingerlings, and Acinetobacter lwoffii (5) isolated from pelletized feed. The occurrence of simultaneous resistance to various antibacterials was frequent. We observe a high frequency of bacteria resistant to 6-10 antibacterials (74 strains), and antibiotic resistance index (ARI) values ranging from 0.38 to 0.48 for the four salmon farms studied. These results suggest that Chilean salmon farms might play a role as reservoirs of antibacterial multiresistant bacteria, thus prompting the necessity for a more restrictive attitude towards the intensive use of antibacterials in salmon farming.     

Naproxen removal from water by chlorination and biofilm processes

Naproxen is an anti-inflammatory pharmaceutical that has been detected in natural and engineered aquatic environments. The primary aim of this research was to study chemical transformations of naproxen following chlorine oxidation, which is common in water and wastewater treatment systems. Synthetic waters containing elevated concentrations of naproxen were oxidized by free chlorine at naproxen:chlorine molar ratios of 0.02-3:1 and pH values of 5-9. The formation of naproxen products was dependent on pH, chlorine dosage and contact time. This study demonstrates that naproxen readily reacts with free chlorine and forms disinfection products. The formation of specific reaction products can vary depending on the characteristics of the water or wastewater and treatment operating conditions. More research is needed to identify intermediate and chemical reaction end products and to understand the reaction kinetics of naproxen chlorination for a range of water and wastewater treatment conditions. A secondary aim of this research was to study effects of naproxen and its chlorination products on biofilm processes, which are common in water and wastewater treatment systems and natural aquatic environments. A bioreactor was fed a naproxen solution and then fed a solution at the same naproxen concentration following contact with free chlorine. Results indicate that naproxen was not degraded biologically for the conditions of this study. In contrast, the naproxen solution containing products of chlorination caused an adverse response by discharging biomass from the bioreactor. Results therefore demonstrate that naproxen products of chlorination can adversely affect a biofilm process, which potentially can impact the performance of biofilm processes in natural and engineered aquatic environments. More research is needed to study naproxen chlorination reactions at low concentrations and in complex matrices, and to understand the toxicological relevance of naproxen and its products of chlorination in natural and engineered aquatic environments.     

The Drying of Pyridine Hydrobromide

1 INTRODUCTIONThe drying of fine chemicals and pharmaceuticals is dominated by a number of special factorscompared to the drying of bulk chemicals.These include:very high value of product;lowthroughputs(typically,100 kg·h~(-1));materials that frequently possess toxic properties andare often sticky,pasty and difficult to handle when wet;the moisture to be evaporated ofteninvolves solvents;and multipurpose processing plants.     

Study of the effect of the monomer pressure on the copolymerization of ethylene with 1-hexene

The effect of ethylene pressure on the copolymerization of ethylene with 1-hexene was studied. The results show an increasing of productivities (g of polymer/n_Zr h) with pressure. This tendency was not observed for the activity (g of polymer/n_Zr h bar) that decreases when pressure is raised. When varing the pressure, the characteristics and properties of the formed copolymers are in accordance with the expectation for changes in the monomer concentration; increasing the pressure causes a decrease in comonomer incorporation. At higher ethylene pressure, the polymer is more crystalline due to less incorporation of 1-hexene and the molecular weight is higher. The density of the copolymers also decreases with comonomer incorporation into the copolymer © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 2567–2574, 1997     

Corrosion Behaviour of Type 316L Stainless Steel in Hot Caustic Aqueous Environments

Metals and Materials International - The corrosion behaviour of type 316L stainless steel in aqueous 30–50&nbsp;wt%. NaOH at temperatures up to 90&nbsp;°C has been elucidated....     

Simulations of Self-Expanding Braided Stent Using Macroscopic Model of NiTi Shape Memory Alloys Covering R-Phase

Self-expanding stents or stentgrafts made from Nitinol superelastic alloy are widely used for a less invasive treatment of disease-induced localized flow constriction in the cardiovascular system. The therapy is based on insertion of a stent into a blood vessel to maintain the inner diameter of the vessel; it provides highly effective results at minimal cost and with reduced hospital stays. However, since stent is an external mechanical healing tool implemented into human body for quite a long time, information on the mechanical performance of it is of fundamental importance with respect to patient’s safety and comfort. Advantageously, computational structural analysis can provide valuable information on the response of the product in an environment where in vivo experimentation is extremely expensive or impossible. With this motivation, a numerical model of a particular braided self-expanding stent was developed. As a reasonable approximation substantially reducing computational demands, the stent was considered to be composed of a set of helical springs with specific constrains reflecting geometry of the structure. An advanced constitutive model for NiTi-based shape memory alloys including R-phase transition was employed in analysis. Comparison to measurements shows a very good match between the numerical solution and experimental results. Relation between diameter of the stent and uniform radial pressure on its surface is estimated. Information about internal phase and stress state of the material during compression loading provided by the model is used to estimate fatigue properties of the stent during cyclic loading.