External validation of the ACC/AHA ASCVD risk score in a Colombian population cohort.

No cardiovascular risk score has included Latin American patients in its development. The ACC/AHA ASCVD risk score has not been validated in Latin America; consequently, its predictive capacity in the population of the region is unknown. The aim of this study is to evaluate the discrimination capacity and calibration of the ACC/AHA ASCVD score to predict the 10-year risk of a cardiovascular event in a primary prevention cohort followed in a Colombian hospital.

[Evaluation of cyclists exposure to air pollution: a literature review].

Objectives: To describe and interpret the methodologies and results of the main studies related to the monitoring of exposure of cyclists to air pollution.

Methods: Research and analysis of national and international research of the last ten years in the Cochrane, Scopus, Embase, Science Direct and Pubmed databases. The search was conducted in August and September 2017 using the following search descriptors for MeSH: air pollution, bicycle riding, environmental exposure, environmental health, exposure by inhalation, environmental pollutants, transportation, public health and toxicology.

A Quest for New Cancer Diagnosis, Prognosis and Prediction Biomarkers and Their Use in Biosensors Development.

Traditional techniques for cancer diagnosis, such as nuclear magnetic resonance, ultrasound and tissue analysis, require sophisticated devices and highly trained personnel, which are characterized by elevated operation costs. The use of biomarkers has emerged as an alternative for cancer diagnosis, prognosis and prediction because their measurement in tissues or fluids, such as blood, urine or saliva, is characterized by shorter processing times. However, the biomarkers used currently, and the techniques used for their measurement, including ELISA, western-blot, polymerase chain reaction (PCR) or immunohistochemistry, possess low sensitivity and specificity.

Crystalline Structure, Synthesis, Properties and Applications of Potassium Hexatitanate: A Review.

Potassium hexatitanate (PHT) with chemical formula KTiO has a tunnel structure formed by TiO octahedra sharing edges or corners and with the potassium atoms located in the tunnels. This material has attracted great interest in the areas of photocatalysis, reinforcement of materials, biomaterials, etc. This work summarizes a large number of studies about methods to prepare PHT since particle size can be modified from millimeter to nanometric scale according to the applied method.

Evaluation of Nanomechanical Properties of Tomato Root by Atomic Force Microscopy.

Here, different tissue surfaces of tomato root were characterized employing atomic force microscopy on day 7 and day 21 of growth through Young's modulus and plasticity index. These parameters provide quantitative information regarding the mechanical behavior of the tomato root under fresh conditions in different locations of the cross-section of root [cell surface of the epidermis, parenchyma (Pa), and vascular bundles (Vb)]. The results show that the mechanical parameters depend on the indented region, tissue type, and growth time.

Efficient Fusion of Liposomes by Nucleobase Quadruple-Anchored DNA.

Anchoring DNA via hydrophobic units into the membrane of vesicles allows tagging of these nanocontainers with sequence information. Moreover, the hybridization of DNA on the surface of liposomes enables sequence specific functionalization, vesicle aggregation, and vesicle fusion. Specifically, DNA-hybridization-based approaches for fusion employing oligonucleotides terminally modified with one or two anchoring units were hindered by a limited degree of full fusion or by significant leakage during fusion.

Correction: Assessing the potential of photosensitizing flavoproteins as tags for correlative microscopy.

Correction for 'Assessing the potential of photosensitizing flavoproteins as tags for correlative microscopy' by Alberto Rodríguez-Pulido et al., Chem. Commun.

Assessing the potential of photosensitizing flavoproteins as tags for correlative microscopy.

Photosensitizing flavoproteins have great potential as tags for correlative light and electron microscopy (CLEM). We examine the photostability of miniSOG mutants and their ability to photo-oxidize diaminobenzidine, both key aspects for CLEM. Our experiments reveal a complex relation between these parameters and the production of different reactive oxygen species.

Occupational exposure to air pollutants: particulate matter and respiratory symptoms affecting traffic-police in Bogotá.

Objectives: Quantifying personal exposure to particles less than 10 micrometres in diameter (PM10) and determining the prevalence of respiratory symptoms in traffic-police officers working in Bogotá's metropolitan area.

Methods: This was a cross-sectional study of 574 traffic-police officers divided into two groups (477 traffic-police and 97 police working in an office). They were given a questionnaire inquiring about respiratory symptoms, toxicological medical evaluation, lung function tests and personal PM10 monitoring.

Probing the shielding properties of aptameric protective groups.

Site-specific derivatization of chemically equivalent functional groups has recently been facilitated by the introduction of high-affinity aptamers as non-covalent protective groups. More specifically, a series of RNA aptamers have proven to be highly efficient in enhancing the regioselectivity of reactions with the aminoglycoside antibiotic neomycin B, which carries several chemically indistinguishable amino and hydroxy groups. Since small-molecule targets tend to exhibit multiple modes of binding with a single aptamer, the impact of secondary binding sites on the regioselectivity should be considered.

[Quantifying polycyclic aromatic hydrocarbons in urine samples taken from traffic police working in Bogota's metropolitan area].

Objective: Quantifying polycyclic aromatic hydrocarbon levels in urine samples taken from a population of traffic police working in the metropolitan area of Bogotá who were occupationally exposed to 1-hydroxypyrene (1-OHP) and 3-hydroxy-benzo[a]pyrene (3-BaP) metabolites from polycyclic aromatic hydrocarbons (PAH) having toxicological interest, related to their detection, and a degree of exposure to particulate material having a size less than 10 micrometres (PM10) and/or other factors.

Methods: A cross-sectional study was made of 524 traffic police, 413 of whom were engaged in operational and 111 in administrative functions. Urine samples were taken from all the individuals included in the study for determining PAH metabolites by gas chromatography/mass spectrometry (GC/MS).

Effect of lipid composition on the structure and theoretical phase diagrams of DC-Chol/DOPE-DNA lipoplexes.

Lipoplexes constituted by calf-thymus DNA (CT-DNA) and mixed cationic liposomes consisting of varying proportions of the cationic lipid 3β-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol hydrochloride (DC-Chol) and the zwitterionic lipid, 1,2-dioleoyl-sn-glycero-3-phosphoetanolamine (DOPE) have been analyzed by means of electrophoretic mobility, SAXS, and fluorescence anisotropy experiments, as well as by theoretically calculated phase diagrams. Both experimental and theoretical studies have been run at several liposome and lipoplex compositions, defined in terms of cationic lipid molar fraction, α, and either the mass or charge ratios of the lipoplex, respectively. The experimental electrochemical results indicate that DC-Chol/DOPE liposomes, with a mean hydrodynamic diameter of around (120 ± 10) nm, compact and condense DNA fragments at their cationic surfaces by means of a strong entropically driven electrostatic interaction.

Experimental and theoretical approach to the sodium decanoate-dodecanoate mixed surfactant system in aqueous solution.

The mixed system consisting of two anionic surfactants of identical headgroups but with 10 and 12 carbon atoms on the hydrophobic tail, sodium decanoate (C(10)Na) and sodium dodecanoate (C(12)Na), has been studied in aqueous solution at 298.15 K by means of conductivity and fluorescence spectroscopy experiments and from a theoretical point of view. The monomeric and micellar phases of the mixed aggregates were analyzed through the experimental determination of the total critical micelle concentration, cmc*, the degree of ionization of the mixed micelle, beta, and the total aggregation number, N*.

A theoretical and experimental approach to the compaction process of DNA by dioctadecyldimethylammonium bromide/zwitterionic mixed liposomes.

The compaction of DNA by cationic liposomes constituted by a mixture of a cationic lipid, dioctadecyldimethylammonium bromide (DODAB), and a zwitterionic lipid, 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) or 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC), has been evaluated by means of experimental studies (electrophoretic mobility, conductometry, cryogenic electron transmission microscopy or cryo-TEM, and fluorescence spectroscopy) as well as theoretical calculations. This information reveals that DODAB/DOPE and DODAB/DLPC liposomes are mostly spherical and unilamellar, with a mean diameter of around 70 and 61 nm, respectively, a bilayer thickness of 4.5 nm, and gel-to-fluid transition temperatures, T(m), of around 19 and 28 degrees C, respectively.

Electrochemical and spectroscopic study of octadecyltrimethylammonium bromide/DNA surfoplexes.

The use of cationic micelles consisting of octadecyltrimethylammonium bromide (C18TAB) to compact calf thymus DNA has been investigated in aqueous buffered solution at 310.15 K by means of conductometry, electrophoretic mobility, and several fluorescence spectroscopy methods. The results indicate that C18TAB micelles, consisting of 44 monomers on average, may compact DNA molecule by an electrostatic interaction that takes place at the cationic spherical micelle surface.

A physicochemical characterization of the interaction between DC-Chol/DOPE cationic liposomes and DNA.

A 1:1 mixture of the cationic lipid 3beta-[ N-( N', N'-dimethylaminoethane)-carbamoyl]cholesterol hydrochloride (DC-Chol) and the zwitterionic lipid, 1,2-dioleoyl- sn-glycero-3-phosphoetanolamine (DOPE), has been used to compact calf-thymus DNA (CT-DNA) in aqueous buffered solution at 298.15 K. The formation process of this lipoplex has been analyzed by means of electrophoretic mobility, cryo-TEM, dynamic light scattering, and fluorescence spectroscopy techniques.

Compaction process of calf thymus DNA by mixed cationic-zwitterionic liposomes: a physicochemical study.

The compaction of calf thymus DNA (CT-DNA) by cationic liposomes constituted by a 1:1 mixture of a cationic lipid, 1,2-distearoyl-3-(trimethylammonio)propane chloride (DSTAP), and a zwitterionic lipid, 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE, null net charge at pH = 7.4), has been evaluated in aqueous buffered solution at 298.15 K by means of conductometry, electrophoretic mobility, cryo-TEM, and fluorescence spectroscopy techniques.