43 research outputs found
Influencia del estilo de vida occidental en la disbiosis y sus consecuencias sobre la salud
La microbiota intestinal es en la actualidad un campo de estudio de creciente interés e investigación. Tal investigación se ha visto potenciada por el desarrollo de las diferentes técnicas de estudio, que han permitido alcanzar un nivel de conocimiento sobre la microbiota insospechado hasta hace unos años. Así, se le han atribuido un número creciente de funciones a este ecosistema presente en nuestro intestino, y se le ha relacionado con diversas condiciones de salud y enfermedad. Se ha puesto en evidencia que resulta fundamental la existencia de unas condiciones de equilibrio y homeostasis en la composición de la microbiota. La alteración de esta beneficiosa composición y función de la microbiota para el organismo podría condicionar o verse implicada en la patogenia de distintas enfermedades y es lo que se ha conocido en la literatura como disbiosis. En el presente artículo de revisión analizaremos la posible implicación de la disbiosis en las alteraciones de la barrera intestinal, como posible mecanismo por el que se asocia a alteraciones y problemas sistémicos. Del mismo modo, teniendo en cuenta la gran cantidad de factores que modifican la microbiota intestinal, la presente revisión trata de encontrar en la literatura médica actual las posibles causas de este proceso, y determinar cuál es su papel e importancia. Se analizará en este contexto la influencia del estilo de vida occidental, evaluando su papel como causa de disbiosis y las consecuencias que trae consigo. Del mismo modo se pretenden identificar las posibles estrategias que conduzcan a emplear este conocimiento como posible armamento preventivo y/o terapéutico frente a la disbiosis
Interaction between lactose and cadmium chloride in aqueous solutions as seen by diffusion coefficients measurements
Diffusion coefficients of an aqueous system containing cadmium chloride 0.100 mol · dm−3 and lactose at different concentrations at 25 °C have been measured, using a conductimetric cell and an automatic apparatus to follow diffusion. The cell relies on an open-ended capillary method and a conductimetric technique is used to follow the diffusion process by measuring the resistance of a solution inside the capillaries, at recorded times. From these results and by ab initio calculations, it was possible to obtain a better understanding of the effect of lactose on transport of cadmium chloride in aqueous solutions
Binary Mutual Diffusion Coefficients of Isoniazid Aqueous Solutions at (298.15 and 310.15) K
Binary mutual diffusion coefficients measured by the Taylor dispersion method in two different laboratories (University of Naples, Federico II, Italy, and University of Coimbra, Portugal) are reported for aqueous solutions of isoniazid at concentrations from (0.000 to 0.100) mol·dm−3 and at two temperatures (298.15 and 310.15) K. The hydrodynamic radii for the isoniazid in aqueous solution are calculated from the experimental results. In addition, the Hartley equation and the experimental diffusion coefficients are used to estimate activity coefficients for aqueous isoniazid at both temperature
Diffusion Coefficients of Copper Chloride in Aqueous Solutions at 298.15 K and 310.15 K
Mutual diffusion coefficients (interdiffusion coefficients) and molar conductivities have been measured for copper(II) chloride in water at 298.15 K and 310.15 K at concentrations between 0.005 mol·dm-3 and 0.05 mol·dm-3. The diffusion coefficients were measured using a conductometric cell. The experimental data are discussed on the basis of the Onsager−Fuoss model. The Nernst diffusion coefficients derived from diffusion (1.297 × 10-9 and 1.690 × 10-9) m2·s-1 and from conductance (1.282 × 10-9 and 1.663 × 10-9) m2·s-1 at two temperatures (298.15 K and 310.15 K, respectively) are in good agreement
Dependence of viscosity and diffusion on β-cyclodextrin and chloroquine diphosphate interactions
Mutual diffusion coefficients of chloroquine diphosphate (CDP) in aqueous solutions both without and with β-cyclodextrin (β-CD) were measured at concentrations from (0.0000 to 0.0100) mol dm−3 and 298.15 K, using the Taylor dispersion technique. Ternary mutual diffusion coefficients (Dik) measured by the same technique are reported for aqueous CDP + β-CD solutions at 298.15 K. The presence of β CD led to relevant changes in the diffusion process, as showed by nonzero values of the cross-diffusion coefficients, D12 and D21 . β-CD concentration gradients produced significant co-current coupled flows of CDP. In addition, the effects of β-CD on the transport of CDP are assessed by comparing the binary diffusion coefficient of aqueous CDP solutions with the main diffusion coefficient (D11 ) measured for ternary {CDP(1) + β-CD(2)} solutions. These observations are supported by viscosity analysis. All data allow to have a better interpretation on the effect of cyclodextrin on the transport behavior of CDP. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Coimbra Chemistry Centre - FundacAo para a Ciencia e a Tecnologia (FCT), Portuguese Agency for Scientific Research [UID/QUI/UI0313/2019]; COMPETE; Ministry of Education, Youth and Sports of the Czech Republic DKRVO [RP/CPS/2020/003]; University of Alcala (Spain)RP/CPS/2020/003; UID/QUI/UI0313/2019; Fundação para a Ciência e a Tecnologia, FCT; Universidad de Alcalá, UAH; Programa Operacional Temático Factores de Competitividade, POF
Effect of hofmeister ions on transport properties of aqueous solutions of sodium hyaluronate
Tracer diffusion coefficients obtained from the Taylor dispersion technique at 25.0◦C were measured to study the influence of sodium, ammonium and magnesium salts at 0.01 and 0.1 mol dm−3 on the transport behavior of sodium hyaluronate (NaHy, 0.1%). The selection of these salts was based on their position in Hofmeister series, which describe the specific influence of different ions (cations and anions) on some physicochemical properties of a system that can be interpreted as a salting-in or salting-out effect. In our case, in general, an increase in the ionic strength (i.e., concentrations at 0.01 mol dm−3 ) led to a significant decrease in the limiting diffusion coefficient of the NaHy 0.1%, indicating, in those circumstances, the presence of salting-in effects. However, the opposite effect (salting-out) was verified with the increase in concentration of some salts, mainly for NH4SCN at 0.1 mol dm−3 . In this particular salt, the cation is weakly hydrated and, consequently, its presence does not favor interactions between NaHy and water molecules, promoting, in those circumstances, less resistance to the movement of NaHy and thus to the increase of its diffusion (19%). These data, complemented by viscosity measurements, permit us to have a better understanding about the effect of these salts on the transport behaviour of NaHy. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Fundacao para a Ciencia e a Tecnologia (FCT) through COMPETE Programme (Operational Programme for Competitiveness) [UIDB/QUI/00313/2020]; Ministry of Education, Youth and Sports of the Czech Republic DKRVO [RP/CPS/2020/003]Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: RP/CPS/2020/003; Fundação para a Ciência e a Tecnologia, FCT: UIDB/QUI/00313/202
Berry Flesh and Skin Ripening Features in Vitis vinifera as Assessed by Transcriptional Profiling
Background
Ripening of fleshy fruit is a complex developmental process involving the differentiation of tissues with separate functions. During grapevine berry ripening important processes contributing to table and wine grape quality take place, some of them flesh- or skin-specific. In this study, transcriptional profiles throughout flesh and skin ripening were followed during two different seasons in a table grape cultivar ‘Muscat Hamburg’ to determine tissue-specific as well as common developmental programs.
Methodology/Principal Findings
Using an updated GrapeGen Affymetrix GeneChip® annotation based on grapevine 12×v1 gene predictions, 2188 differentially accumulated transcripts between flesh and skin and 2839 transcripts differentially accumulated throughout ripening in the same manner in both tissues were identified. Transcriptional profiles were dominated by changes at the beginning of veraison which affect both pericarp tissues, although frequently delayed or with lower intensity in the skin than in the flesh. Functional enrichment analysis identified the decay on biosynthetic processes, photosynthesis and transport as a major part of the program delayed in the skin. In addition, a higher number of functional categories, including several related to macromolecule transport and phenylpropanoid and lipid biosynthesis, were over-represented in transcripts accumulated to higher levels in the skin. Functional enrichment also indicated auxin, gibberellins and bHLH transcription factors to take part in the regulation of pre-veraison processes in the pericarp, whereas WRKY and C2H2 family transcription factors seems to more specifically participate in the regulation of skin and flesh ripening, respectively.
Conclusions/Significance
A transcriptomic analysis indicates that a large part of the ripening program is shared by both pericarp tissues despite some components are delayed in the skin. In addition, important tissue differences are present from early stages prior to the ripening onset including tissue-specific regulators. Altogether, these findings provide key elements to understand berry ripening and its differential regulation in flesh and skin.This study was financially supported by GrapeGen Project funded by Genoma España within a collaborative agreement with Genome Canada. The authors also thank The Ministerio de Ciencia e Innovacion for project BIO2008-03892 and a bilateral collaborative grant with Argentina (AR2009-0021). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewe
Advanced Studies on Toxic Chemicals: Properties and Characteristics
Examining the toxic scope of substances used in daily life (referred to as Contaminants of Emerging Concern (CEC)) in food, medicines, utensils, work and other industries, provides us with interesting information that will help us to prevent and recover from the dangerous organic unbalances that these substances can cause [...
Transport Properties for Pharmaceutical Controlled-Release Systems: A Brief Review of the Importance of Their Study in Biological Systems
The goal of this work was to comprehensive study the transport properties of controlled-release systems for the safe and reliable delivery of drugs. Special emphasis has been placed on the measurement of the diffusion of drugs, alone or in combination with carrier molecules for enhanced solubility and facilitated transport. These studies have provided detailed comprehensive information—both kinetic and thermodynamic—for the design and operation of systems for the controlled release and delivery of drugs. Cyclodextrins are among the most important carriers used in these systems. The basis for their popularity is the ability of these materials to solubilize poorly soluble drugs, generally resulting in striking increases in their water solubilities. The techniques used in these investigations include pulse voltammetry, nuclear magnetic resonance (NMR) and Raman spectroscopy, ultrasonic relaxation, and dissolution kinetics. Transport in these systems is a mutual diffusion process involving coupled fluxes of drugs and carrier molecules driven by concentration gradients. Owing to a strong association in these multicomponent systems, it is not uncommon for a diffusing solute to drive substantial coupled fluxes of other solutes, mixed electrolytes, or polymers. Thus, diffusion data, including cross-diffusion coefficients for coupled transport, are essential in order to understand the rates of many processes involving mass transport driven by chemical concentration gradients, as crystal growth and dissolution, solubilization, membrane transport, and diffusion-limited chemical reactions are all relevant to the design of controlled-release systems. While numerous studies have been carried out on these systems, few have considered the transport behavior for controlled-release systems. To remedy this situation, we decided to measure mutual diffusion coefficients for coupled diffusion in a variety of drug⁻carrier solutions. In summary, the main objective of the present work was to understand the physical chemistry of carrier-mediated transport phenomena in systems of controlled drug release