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1.
BMC Public Health ; 24(1): 739, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38454414

ABSTRACT

BACKGROUND: The influence of food advertising on food preferences and consumption could also contribute to the socio-economic inequalities among Spanish children in terms of eating habits and childhood obesity. Although the main food advertising channel targeted at children in Spain is television, available studies estimate exposure indirectly by combining content data with audience data. The aim of this study was therefore to describe the frequency of exposure to television advertising of unhealthy foods and drinks, measured directly, among Spanish children and adolescents, and analyse its socio-economic inequalities. METHODS: Observational study of television advertising impacts in a sample of 1590 children aged 4 to 16 years drawn from a consumer panel representative of the Spanish population in this age group, over the course of a full week of broadcasting in February 2022. The sample was obtained through stratified random sampling by Autonomous Region, with quotas being set by reference to socio-demographic variables. Exposure was measured with an audiometer, and the nutrient content of the food and drink advertised was analysed using the nutrient profile of the WHO Regional Office for Europe. We used the Chi-squared test to analyse possible differences in advertising coverage by socio-economic level. RESULTS: The participants saw a weekly mean of 82.4 food and drink commercials, 67.4 of which were for unhealthy products (81.8%), mostly outside the child-protection time slot. On average, low-social class participants received 94.4% more impacts from unhealthy food and drink advertising than did high-class participants (99.9 vs. 51.4 respectively). The mean advertising coverage of unhealthy foods and drinks was 71.6% higher in low-class than in high-class participants (10.9% vs. 18.7%; p = 0.01). CONCLUSION: Spanish children and adolescents received an average of 10 impacts per day from television spots for unhealthy foods and drinks. The exposure of low-class children is double that of high-class children, a finding compatible with the high prevalence of childhood obesity in Spain and the related socio-economic inequalities. To protect Spanish minors from the harmful effects of food advertising and reduce the related social health inequalities would require the implementation of a 24:00 watershed for unhealthy food advertising on television.


Subject(s)
Advertising , Pediatric Obesity , Adolescent , Child , Humans , Beverages , Food , Food Industry , Pediatric Obesity/epidemiology , Pediatric Obesity/prevention & control , Socioeconomic Factors , Spain/epidemiology , Television , Child, Preschool
2.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1551002

ABSTRACT

Introducción: La enfermedad inflamatoria pélvica aguda es una entidad frecuente en mujeres jóvenes en edad reproductiva, y constituye la causa principal de infertilidad. La búsqueda de un tratamiento antiinflamatorio eficaz y seguro que alivie el dolor, evite complicaciones y secuelas, es una prioridad para su tratamiento. Objetivo: Evaluar la eficacia y seguridad del tratamiento con Proctokinasa® en la enfermedad inflamatoria pélvica aguda grados I y II. Materiales y métodos: Se desarrolló un ensayo clínico, controlado, abierto, de enero de 2017 a enero de 2018, que incluyó 76 pacientes con diagnóstico de enfermedad inflamatoria pélvica aguda en la atención primaria de salud, quienes fueron asignadas aleatoriamente a dos grupos de tratamiento: grupo principal Proctokinasa®, que recibió una unidad/8 h por 2 días, y el grupo Piroxicam, un supositorio de 20 mg/24 h por 7 días. La antibioticoterapia oral recomendada se inició simultáneamente. Se evaluó la respuesta clínica y ecográfica al tratamiento. Los eventos adversos fueron evaluados. Resultados: Se constató respuesta clínica a partir de las 72 horas de tratamiento en más del 50 % de las pacientes en ambos grupos, y fue del 100 % de los casos para el grupo Proctokinasa® en las dos últimas evaluaciones realizadas (días 10 y 15). Se evidenció la remisión de las alteraciones ecográficas en el 96,9 % del grupo Proctokinasa®. Los eventos adversos fueron escasos y leves. Conclusiones: El empleo de Proctokinasa® resultó eficaz y seguro en el tratamiento de la enfermedad inflamatoria pélvica aguda grados I y II.


Introduction: Acute pelvic inflammatory disease is a common entity in young women of reproductive age and it is a leading cause of infertility. The search for an effective and safe anti-inflammatory treatment that relieves pain, avoids complications and sequels, it is priority for its treatment. Objective: To evaluate the efficacy and safety of the treatment with Proctokinasa® in acute pelvic inflammatory disease grades I and II. Materials and methods: An open, controlled clinical trial was carried out from January 2017 to January 2018 which included 76 patients diagnosed with acute pelvic inflammatory disease in primary health care; they were randomize assigned to two treatment groups: Proctokinasa® main group, who received one unity/8h for 2 days, and the Piroxican group, 1 suppository of 20 mg/24h per 7 days. The recommended oral antibiotic therapy was started simultaneously. Clinical and ultrasound response to treatment were evaluated. Adverse events were evaluated. Results: Clinical response was stated after 72 hours of treatment inmore than 50% of the patients in both groups, and it was 100% for the Proctokinasa® group in the last two evaluations (days 10 and 15). Remission of ultrasound alterations was evident in 96.9% of the Proctokinasa® group. Adverse events were few and mild. Conclusions: The use of Proctokinasa® was effective and safe in the treatment of acute pelvic inflammatory disease grades I and II.

3.
Int J Biol Macromol ; 250: 126009, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37536414

ABSTRACT

Glycosyltransferases catalyze the regioselective glycosylation of polyphenolic compounds, increasing their solubility without altering their antioxidant properties. Leloir-type glycosyltransferases require UDP-glucose as a cofactor to glycosylate a hydroxyl of the polyphenol, which is expensive and unstable. To simplify these processes for industrial implementation, the preparation of self-sufficient heterogeneous biocatalysts is needed. In this study, a glycosyltransferase and a sucrose synthase (as an UDP-regenerating enzyme) were co-immobilized onto porous agarose-based supports coated with polycationic polymers: polyethylenimine and polyallylamine. In addition, the UDP cofactor was strongly ionically adsorbed and co-immobilized with the enzymes, eliminating the need to add it separately. Thus, the optimal self-sufficient heterogeneous biocatalyst was able to catalyze the glycosylation of three polyphenolic compounds (piceid, phloretin and quercetin) with in situ regeneration of the UDP-glucose, allowing multiple consecutive reaction cycles without the addition of exogenous cofactor. A TTN value of 50 (theoretical maximum) was obtained in the reaction of piceid glycosylation, after 5 reaction cycles, using the self-sufficient biocatalyst based on an improved sucrose synthase variant. This result was 5-fold higher than the obtained using soluble cofactor and the co-immobilized enzymes, and much higher than those reported in the literature for similar processes.

4.
ChemSusChem ; 15(16): e202200811, 2022 Aug 19.
Article in English | MEDLINE | ID: mdl-35671069

ABSTRACT

6-Aminocaproic acid (6ACA) is a key building block and an attractive precursor of caprolactam, which is used to synthesize nylon 6, one of the most common polymers manufactured nowadays. (Bio)-production of platform chemicals from renewable feedstocks is instrumental to tackle climate change and decrease fossil fuel dependence. Here, the cell-free biosynthesis of 6ACA from 6-hydroxycaproic acid was achieved using a co-immobilized multienzyme system based on horse liver alcohol dehydrogenase, Halomonas elongata transaminase, and Lactobacillus pentosus NADH oxidase for in-situ cofactor recycling, with >90 % molar conversion (m.c.) The integration of a step to synthesize hydroxy-acid from lactone by immobilized Candida antarctica lipase B resulted in >80 % m.c. of ϵ-caprolactone to 6ACA, >20 % of δ-valerolactone to 5-aminovaleric acid, and 30 % of γ-butyrolactone to γ-aminobutyric acid in one-pot batch reactions. Two serial packed-bed reactors were set up using these biocatalysts and applied to the continuous-flow synthesis of 6ACA from ϵ-caprolactone, achieving a space-time yield of up to 3.31 g6ACA h-1 L-1 with a segmented liquid/air flow for constant oxygen supply.


Subject(s)
Caprolactam , Animals , Biocatalysis , Caproates , Caprolactam/analogs & derivatives , Enzymes, Immobilized/metabolism , Horses , Lactones , Polymers
5.
Chembiochem ; 23(8): e202200108, 2022 04 20.
Article in English | MEDLINE | ID: mdl-35189014

ABSTRACT

The synthesis of enantiopure chiral amines from racemic alcohols is a key transformation in the chemical industry, e. g., in the production of active pharmaceutical ingredients (APIs). However, this reaction remains challenging. In this work, we propose a one-pot enzymatic cascade for the direct conversion of a racemic alcohol into either (S)- or (R)-enantiomers of the corresponding amine, with in-situ cofactor recycling. This enzymatic cascade consists of two enantio-complementary alcohol dehydrogenases, both NADH and NADPH oxidase for in-situ recycling of NAD(P)+ cofactors, and either (S)- or (R)-enantioselective transaminase. This cell-free biocatalytic system has been successfully applied to the conversion of racemic 4-phenyl-2-butanol into the high value (S)- or (R)-enantiomers of the amine reaching good (73 % (S)) and excellent (>99 % (R)) enantioselectivities.


Subject(s)
Amines , Butanols , 1-Butanol , Alcohol Dehydrogenase/metabolism , Alcohols , Biocatalysis , Stereoisomerism
6.
ACS Sustain Chem Eng ; 10(7): 2388-2396, 2022 Feb 21.
Article in English | MEDLINE | ID: mdl-35223215

ABSTRACT

Electrochemical continuous-flow reactors offer a great opportunity for enhanced and sustainable chemical syntheses. Here, we present a novel application of electrochemical continuous-flow oscillatory baffled reactors (ECOBRs) that combines advanced mixing features with electrochemical transformations to enable efficient electrochemical oxidations under continuous flow at a millimeter distance between electrodes. Different additive manufacturing techniques have been employed to rapidly fabricate reactors. The electrochemical oxidation of NADH, a very sensitive substrate key for the regeneration of enzymes in biocatalytic transformations, has been employed as a benchmark reaction. The oscillatory conditions improved bulk mixing, facilitating the contact of reagents to electrodes. Under oscillatory conditions, the ECOBR demonstrated improved performance in the electrochemical oxidation of NADH, which is attributed to improved mass transfer associated with the oscillatory regime.

7.
Rev. medica electron ; 44(1)feb. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1409716

ABSTRACT

RESUMEN Introducción: la enfermedad inflamatoria pélvica aguda es una entidad frecuente en mujeres jóvenes en edad reproductiva, y constituye causa de infertilidad y otras complicaciones. Objetivo: caracterizar el comportamiento de la enfermedad inflamatoria pélvica aguda en pacientes atendidas en el Policlínico Docente Samuel Fernández, del municipio Matanzas, en el período de enero de 2017 a enero de 2018. Materiales y métodos: se realizó un estudio descriptivo, longitudinal y prospectivo a 76 mujeres, a las que se les hizo caracterización sociodemográfica y clínico-ecográfica, que permitió su clasificación como pacientes con enfermedad inflamatoria pélvica aguda leve-moderada, requerida de tratamiento y seguimiento en atención primaria. Se evaluó la respuesta clínico-ecográfica al tratamiento médico indicado, a partir de la disminución de la intensidad del dolor pélvico y de las modificaciones de los hallazgos ecográficos iniciales. Resultados: la enfermedad inflamatoria pélvica aguda leve-moderada representó el 87,4 % de los casos evaluados en Consulta Ginecológica de la atención primaria de salud, en el período estudiado. La media de edad fue de 31,2 años. Clínicamente predominaron los casos con dolor severo. El hallazgo ecográfico inicial más frecuente fue el de anejos engrosados. La antibioticoterapia oral combinada y el uso de antiinflamatorios fue la terapia médica empleada, con resultados clínico-ecográficos favorables en el 98,4 y el 92,2 % de los casos, respectivamente. Conclusiones: la enfermedad inflamatoria pélvica leve-moderada resultó una entidad frecuente en el Servicio de Ginecología de la atención primaria de salud en el período estudiado, con evolución satisfactoria al tratamiento médico.


ABSTRACT Introduction: acute inflammatory pelvic disease is a frequent entity in young women in reproductive age, and is cause of infertility and other complications. Objective: to characterize the behavior of the acute inflammatory pelvic disease in patients attended at the TeachingPoliclinic Samuel Fernandez, of the municipality of Matanzas, in the period from January 2017 to January 2018. Materials and methods: a descriptive, longitudinal and prospective study was carried out in 76 women, who were object of socio-demographic and clinic-echographyc characterization that allowed their classification as patients with mild-moderated acute inflammatory pelvic disease requiring treatment and follow up in primary care services. The clinic-echographyc answer to medical treatment was evaluated from the decrease of the intensity of the pelvic pain and the modification of the baseline echographyc findings. Results: mild-moderated acute inflammatory pelvic disease represented 87.4 % of the cases evaluated in the primary care Gynecological consultation in the studied period. The average age was 31.2 years. The cases with severe pain predominated clinically. The most frequent baseline echographyc finding was increased annexes. Oral combined antibiotic therapy and the use of anti-inflammatory drugs was the used medical therapy, with favorable clinic-echographyc results in 98.4 % and 92.2 % of cases respectively. Conclusions: mild-moderated inflammatory pelvic disease was a frequent entity in the Gynecology service of the primary health care in the studied period, with satisfactory evolution to medical treatment.

8.
Animals (Basel) ; 11(8)2021 Aug 03.
Article in English | MEDLINE | ID: mdl-34438748

ABSTRACT

Seventy-eight calves from Asturiana de los Valles, Retinta, and Rubia Gallega breeds, under extensive and intensive farm systems and animal mixing and non-mixing conditions, and during the transport and lairage in slaughterhouses, were studied. This research aimed to study the effect of breed, farm system and mixing conditions on serum biomarkers (cortisol, lactate, glucose, serum amyloid A, haptoglobin, and C-reactive protein) and their relationship with pHu at slaughter time, and to evaluate the response of the serum biomarkers of calves throughout fattening period. Moreover, this study aims to evaluate the response of the biomarkers in each breed during the fattening period. At slaughter time, cortisol and lactate were affected by BreedxFarm; Retinta showed the opposite pattern to the others and revealed the highest glucose in extensive farm systems. Rubia Gallega in mixing revealed the highest Amyloid A and haptoglobin. Extensive calves in mixing conditions showed the highest glucose. There was a relationship among the variables cortisol, lactate, Amyloid A, and pHu. Slaughter time was a major stressor, and the stress response was mainly affected by breed. At slaughter, several biomarkers should be considered.

9.
Green Chem ; 23(12): 4594-4603, 2021 May 24.
Article in English | MEDLINE | ID: mdl-34220333

ABSTRACT

As an alternative to classical synthetic approaches for the production of betazole drug, a one-pot biocatalytic system for this pharmaceutical molecule from its alcohol precursor has been developed. An ω-transaminase, an alcohol dehydrogenase and a water-forming NADH oxidase for in situ cofactor recycling have been combined to catalyse this reaction, yielding 75% molar conversion in batch reactions with soluble enzymes. This multienzyme system was then co-immobilised through a newly established protocol for sequential functionalization of a methacrylate-based porous carrier to enable tailored immobilisation chemistries for each enzyme. This pluri-catalytic system has been set up in a continuous flow packed-bed reactor, generating a space-time yield of up to 2.59 g L-1 h-1 with 15 min residence and a constant supply of oxygen for in situ cofactor recycling through a segmented air-liquid flow. The addition of an in-line catch-and-release column afforded >80% product recovery.

10.
Polymers (Basel) ; 13(11)2021 May 30.
Article in English | MEDLINE | ID: mdl-34070820

ABSTRACT

New bio-based polymers capable of either outperforming fossil-based alternatives or possessing new properties and functionalities are of relevant interest in the framework of the circular economy. In this work, a novel bio-based polycarvone acrylate di-epoxide (PCADE) was used as an additive in a one-step straightforward electrospinning process to endow the fibres with functionalisable epoxy groups at their surface. To demonstrate the feasibility of the approach, poly(vinylidene fluoride) (PVDF) fibres loaded with different amounts of PCADE were prepared. A thorough characterisation by TGA, DSC, DMTA and XPS showed that the two polymers are immiscible and that PCADE preferentially segregates at the fibre surface, thus developing a very simple one-step approach to the preparation of ready-to-use surface functionalisable fibres. We demonstrated this by exploiting the epoxy groups at the PVDF fibre surface in two very different applications, namely in epoxy-based carbon fibre reinforced composites and membranes for ω-transaminase enzyme immobilisation for heterogeneous catalysis.

11.
Methods Mol Biol ; 2100: 159-174, 2020.
Article in English | MEDLINE | ID: mdl-31939122

ABSTRACT

The immobilization of proteins on heterofunctional amino-epoxy and amino-glyoxyl supports is described in this chapter. Immobilization on both supports is performed through a two-step mechanism: in the first step, the enzyme is physically adsorbed to the support, and in the second step, the intramolecular covalent attachment between the adsorbed enzyme and the support is promoted. On the one hand, amino-epoxy supports present a ratio between amino and epoxy groups of 1:1 to allow the rapid adsorption of the enzyme and promote a strong multipoint covalent linkage. On the other hand, amino-glyoxyl supports contain the highest concentration of glyoxyl groups capable of reacting covalently with primary amino groups on the enzyme surface to promote increased rigidification. The intensity of the covalent enzyme-support interaction can be modulated by modifying the ratio between glyoxyl and amino groups of the support. These heterofunctional supports are able to immobilize and rigidify proteins through different orientations, leading to biocatalysts with different enzyme properties (activity, stability, and selectivity).


Subject(s)
Enzymes, Immobilized/chemistry , Adsorption , Biocatalysis , Chemical Phenomena , Cross-Linking Reagents/chemistry , Enzyme Activation , Enzyme Stability , Epoxy Resins/chemistry , Hydrogen-Ion Concentration , Proteins , Sepharose/chemistry
12.
Curr Opin Chem Biol ; 55: 1-8, 2020 04.
Article in English | MEDLINE | ID: mdl-31865258

ABSTRACT

Enzymatic immobilization has been at the forefront of applied biocatalysis as it enables convenient isolation and reuse of the catalyst if the target reaction is conducted in batch, and it has opened up significant opportunities to conduct biocatalysis in continuous mode. Over the last few years, an array of techniques to immobilize enzymes have been developed, spanning from covalent multipoint attachment to noncovalent electrostatic strategies to rational architecture to suitably orient the enzyme(s). In addition, new materials have been adapted to support biological catalysts. Here, we discuss the advances of the last two years in enzyme immobilization for continuous flow applications.


Subject(s)
Coenzymes/chemistry , Coenzymes/metabolism , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Biocatalysis , Epoxy Compounds/chemistry , Histidine/chemistry , Hydrogels/chemistry , Oxidation-Reduction , Printing, Three-Dimensional , Static Electricity , Surface Properties
13.
Bioresour Technol ; 266: 249-258, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29982045

ABSTRACT

The present study focuses on the development and optimization of a packed-bed reactor (PBR) for continuous production of xylooligosaccharides (XOS) from xylan. For this purpose, three different methacrylic polymer-based supports (Relizyme R403/S, Purolite P8204F and Purolite P8215F) activated with glyoxyl groups were morphologically characterized and screened for the multipoint covalent immobilization of a xylanase. Based on its physical and mechanical properties, maximum protein loading and thermal stability, Relizyme R403/S was selected to set up a PRB for continuous production of XOS from corncob xylan. The specific productivity for XOS at 10 mL/min flow rate was 3277 gXOS genzyme-1 h-1 with a PBR. This PBR conserved >90% of its initial activity after 120 h of continuous operation.


Subject(s)
Glucuronates/metabolism , Oligosaccharides/metabolism , Endo-1,4-beta Xylanases , Hydrolysis , Polymers , Xylans
14.
N Biotechnol ; 44: 50-58, 2018 Sep 25.
Article in English | MEDLINE | ID: mdl-29704649

ABSTRACT

Xylooligosaccharides display interesting prebiotic effects on human health. The endoxylanase Xys1Δ, from Streptomyces halstedii JM8, was immobilized and stabilized on glyoxyl-agarose beads by multipoint covalent attachment using a novel strategy based on surface coating with a multilayer of polymers. The optimal modification consisted of surface coating with a bilayer formed by a layer of derived dextran polymers and a layer of polyethylenimine. The optimized biocatalyst was 550-fold more stable than one-point covalent immobilized Xys1Δ (at 70 °C, pH 7). This biocatalyst was tested for the production of xylooligosaccharides from soluble xylans from various sources. Hydrolysis of beechwood, wheat straw and corncob xylans was 93% in 4 h, 44% in 5 h and 100% in 1 h, respectively. Maximum values of xylooligosaccharides were found for beechwood at 20.6 mg/mL, wheat at 12.5 mg/mL and corncob at 30.4 mg/mL. The optimized biocatalyst was reused for 15 reaction cycles without affecting its catalytic activity.


Subject(s)
Bacterial Proteins/chemistry , Endo-1,4-beta Xylanases/chemistry , Enzymes, Immobilized/chemistry , Glucuronates/chemistry , Oligosaccharides/chemistry , Streptomyces/enzymology , Xylans/chemistry , Humans
15.
Appl Biochem Biotechnol ; 182(1): 349-366, 2017 May.
Article in English | MEDLINE | ID: mdl-27882482

ABSTRACT

ß-Xylosidases are critical for complete degradation of xylan, the second main constituent of plant cell walls. A minor ß-xylosidase (BXYL II) from Penicillium janczewskii was purified by ammonium sulfate precipitation (30% saturation) followed by DEAE-Sephadex chromatography in pH 6.5 and elution with KCl. The enzyme presented molecular weight (MW) of 301 kDa estimated by size exclusion chromatography. Optimal activity was observed in pH 3.0 and 70-75 °C, with higher stability in pH 3.0-4.5 and half-lives of 11, 5, and 2 min at 65, 70, and 75 °C, respectively. Inhibition was moderate with Pb+2 and citrate and total with Cu+2, Hg+2, and Co+2. Partially purified BXYL II and BXYL I (the main ß-xylosidase from this fungus) were individually immobilized and stabilized in glyoxyl agarose gels. At 65 °C, immobilized BXYL I and BXYL II presented half-lives of 4.9 and 23.1 h, respectively, therefore being 12.3-fold and 33-fold more stable than their unipuntual CNBr derivatives (reference mimicking soluble enzyme behaviors). During long-term incubation in pH 5.0 at 50 °C, BXYL I and BXYL II glyoxyl derivatives preserved 85 and 35% activity after 25 and 7 days, respectively. Immobilized BXYL I retained 70% activity after 10 reuse cycles of p-nitrophenyl-ß-D-xylopyranoside hydrolysis.


Subject(s)
Enzymes, Immobilized/chemistry , Fungal Proteins/chemistry , Penicillium/enzymology , Xylosidases/chemistry , Cations, Divalent , Citric Acid/chemistry , Cobalt/chemistry , Copper/chemistry , Fungal Proteins/isolation & purification , Glycosides/chemistry , Glyoxylates/chemistry , Hydrogen-Ion Concentration , Kinetics , Lead/chemistry , Mercury/chemistry , Molecular Weight , Penicillium/chemistry , Sepharose/chemistry , Substrate Specificity , Xylosidases/isolation & purification
16.
J Phys Chem A ; 119(3): 525-34, 2015 Jan 22.
Article in English | MEDLINE | ID: mdl-25531557

ABSTRACT

Monoaza- and diaza-derivatives of malondialdehydes, in short aminoacroleins and vinamidines, are prototypical examples of open-chain structures prone to π-electron delocalization, for which intramolecular hydrogen bonding enhances (or diminishes) their pseudoaromaticity depending on the substitution pattern. This interplay is illustrated herein by DFT-based calculations of aromaticity indices in the gas phase and polar solvents. Elucidation of transition structures involved in tautomeric conversions helps to solve how the intramolecular hydrogen transfer occurs. While TSs exhibit a high degree of aromaticity, the dichotomy between forward and backward pathways points to a complex trajectory. Addition of thermal corrections to the electronic energy decreases both the enthalpy and free energy leading to negative ΔH(‡) and ΔG(‡) values. This variational effect accounts for the otherwise elusive distinction between transition structures and saddle points (usually overlooked for high electronic barriers). Also, this rationale fits well within the framework of Marcus' theory.


Subject(s)
Acrolein/chemistry , Hydrogen/chemistry , Malondialdehyde/chemistry , Vinblastine/analogs & derivatives , Acrolein/analogs & derivatives , Hydrogen Bonding , Molecular Structure , Quantum Theory , Thermodynamics , Vinblastine/chemistry
17.
Org Biomol Chem ; 12(44): 8997-9010, 2014 Nov 28.
Article in English | MEDLINE | ID: mdl-25286414

ABSTRACT

Mono- and diaza-derivatives of malondialdehydes, namely 3-alkyl(aryl)amino-2-arylacroleins and 1,5-dialkyl(aryl)-3-arylvinamidines are open-chain systems in which extended electron delocalization and pseudoaromaticity can be envisaged. A set of diversely functionalized compounds has been synthesized and characterized by spectroscopic data and X-ray diffractometry. Quantum-chemical calculations were performed for all possible neutral tautomers and conformers in the gas phase and compared to those in polar solvents (CHCl3, DMSO, and EtOH) at the M06-2X/6-311++G(d,p) level. Tautomeric equilibria and conformational preferences can be rationalized in terms of structural factors, which can be roughly estimated as summation or subtractions of intramolecular interactions. As expected, a key role is played by intramolecular hydrogen bonds whose strength varies from the gas phase to polar ethanol. This issue also delves into the concept of resonance-assisted H-bond, where the donor and acceptor atoms are connected by a π-conjugated system. The most stable conformers (structures a and c) possess a high degree of pseudoaromaticity as inferred from HOMA indexes and other delocalization parameters.

18.
Edumecentro ; 5(2): 146-159, mayo-ago. 2013. ilus
Article in Spanish | LILACS | ID: lil-679938

ABSTRACT

Para la disciplina Farmacología y sus asignaturas en la carrera de Medicina, aparecen contemplados, desde sus programas, aspectos que tributan al cumplimiento de acciones esenciales de las estrategias curriculares propuestas para el perfeccionamiento del proceso de formación del profesional médico. De estas, la de mayor presencia resulta ser la de Medicina Natural y Tradicional. El presente trabajo muestra con un enfoque integrador la experiencia de implementación que se ha venido desarrollando desde el curso 2011-2012 desde la asignatura Farmacología I en la Universidad de Ciencias Médicas de Matanzas, y que ha conducido al fortalecimiento del trabajo metodológico de los profesores y al perfeccionamiento del proceso enseñanza-aprendizaje.


In medical undergraduate studies, the discipline of Pharmacology and its subjects include in their programs aspects that support the implementation of essential actions of the curriculum strategies proposed for the improvement of the medical professional training process. Of these, the most common one turns out to be Natural and Traditional Medicine. This study shows, with an integrated approach, the implementation experience that has been developing since the 2011-2012 academic year in the subject Pharmacology I at the Medical University of Matanzas, which has led to the strengthening of the methodological work of teachers and the improvement of the teaching-learning process.


Subject(s)
Pharmacology , Teaching , Educational Measurement , Methodology as a Subject , Learning
19.
Rev Edumecentro ; 5(2)abr. 2013.
Article in Spanish | CUMED | ID: cum-54488

ABSTRACT

Para la disciplina Farmacología y sus asignaturas en la carrera de Medicina, aparecen contemplados, desde sus programas, aspectos que tributan al cumplimiento de acciones esenciales de las estrategias curriculares propuestas para el perfeccionamiento del proceso de formación del profesional médico. De estas, la de mayor presencia resulta ser la de Medicina Natural y Tradicional. El presente trabajo muestra con un enfoque integrador la experiencia de implementación que se ha venido desarrollando desde el curso 2011-2012 desde la asignatura Farmacología I en la Universidad de Ciencias Médicas de Matanzas, y que ha conducido al fortalecimiento del trabajo metodológico de los profesores y al perfeccionamiento del proceso enseñanza-aprendizaje(AU)


Subject(s)
Methodology as a Subject , Teaching , Learning , Pharmacology
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