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1.
J Chem Phys ; 161(14)2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39387406

RESUMEN

Accurately predicting spectra for heavy elements, often open-shell systems, is a significant challenge typically addressed using a single cluster approach with a fixed coordination number. Developing a realistic model that accounts for temperature effects, variable coordination numbers, and interprets experimental data is even more demanding due to the strong solute-solvent interactions present in solutions of heavy metal cations. This study addresses these challenges by combining multiple methodologies to accurately predict realistic spectra for highly charged metal cations in aqueous media, with a focus on the electronic absorption spectrum of Ce3+ in water. Utilizing highly correlated relativistic quantum mechanical (QM) wavefunctions and structures from molecular dynamics (MD) simulations, we show that the convolution of individual vertical transitions yields excellent agreement with experimental results without the introduction of empirical broadening. Good results are obtained for both the normalized spectrum and that of absolute intensity. The study incorporates a statistical machine learning algorithm, Gaussian Mixture Models-Nuclear Ensemble Approach (GMM-NEA), to convolute individual spectra. The microscopic distribution provided by MD simulations allows us to examine the contributions of the octa- and ennea-hydrate of Ce3+ in water to the final spectrum. In addition, the temperature dependence of the spectrum is theoretically captured by observing the changing population of these hydrate forms with temperature. We also explore an alternative method for obtaining statistically representative structures in a less demanding manner than MD simulations, derived from QM Wigner distributions. The combination of Wigner-sampling and GMM-NEA broadening shows promise for wide application in spectroscopic analysis and predictions, offering a computationally efficient alternative to traditional methods.

2.
Rev Bras Parasitol Vet ; 33(2): e020523, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38985054

RESUMEN

Sarcoptic mange or scabies is a contagious parasitic skin disease that affects a wide range of domestic and wildlife species. A cross-sectional study was carried out to determine the prevalence, molecular identification, and characteristics of sarcoptic mange in vicuñas. A total of 3,274 vicuñas were examined. Following ritual harvesting events ("chaccus") in 13 Andean communities. The presence of mange mites was determined by the skin scraping technique and confirmed by PCR analysis using specific primers for the ITS2 gene of Sarcoptes scabiei. The presence of mange mites was also confirmed by microscopy using samples taken from wallows. A data collection form was used to register the characteristics of the vicuñas sampled. The prevalence of sarcoptic mange was 4.9% (95% CI: 4.1 - 5.6%). All samples from wallows tested positive (9/9). Importantly, the presence of the species S. scabiei was molecularly confirmed. Adult females with regular body condition were more susceptible to sarcoptic mange, although the lesions were mild. This study confirms the presence of S. scabiei in semi-captive vicuñas and points to the possible role of wallows in the dissemination of Sarcoptes mites.


Asunto(s)
Sarcoptes scabiei , Escabiosis , Escabiosis/epidemiología , Escabiosis/veterinaria , Estudios Transversales , Animales , Perú/epidemiología , Femenino , Masculino , Prevalencia , Sarcoptes scabiei/genética
3.
J Chem Phys ; 160(19)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38747938

RESUMEN

We have applied a recently developed general purpose acetonitrile force field based on first-principles calculations to simulate acetonitrile in the gas phase at different temperatures and densities. These conditions range from nearly ideal to real gas phase behavior and condensation. The molecular dynamics simulation results agree fairly well with the experimental studies available in the literature on the gas samples. The structural analysis of aggregates and their associated interaction energies is examined and related to the early model proposed on molecular association and equilibrium determining the non-ideal behavior. The formation of dimers is mainly responsible for the non-ideal behavior of the gas at very low density, confirming suggested models based on previous experimental studies. However, when the density of the sample rises, the level of aggregation increases and the simple concept of dimerization does not hold anymore. The real behavior adopted by the gas is related to the distribution of molecular structures observed. The macroscopical view of a real gas as a generic interparticle interaction system without a defined form may then be rationalized on the basis of a defined molecular association originated by a distribution of aggregates at the low density regime. The sample with the highest density (∼1.4 × 103 mol m-3) at the lowest temperature exhibits a massive aggregation where most of the acetonitrile (ACN) molecules in the simulation box form a big cluster. Its radial distribution function is similar to that of the liquid ACN. This strongly inhomogeneous distribution in the box can be considered a condensation in the gas phase under specific density-T conditions. This formation opens the door to the potential tuning of its solvent properties as a function of its size in these nanodroplets that in turn are controlled by the density-T conditions.

4.
Humanidad. med ; 24(1)abr. 2024.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1557984

RESUMEN

El escenario de las nuevas tecnologías de la información y la comunicación han transformado los modos de evaluar la publicación científica. Variedad instrumentos e indicadores impactan en los procesos de evaluación. El objetivo de este trabajo es ofrecer una valoración de los procedimientos utilizados en base al uso del conocimiento. Se evidencia a necesidad de avanzar en cuanto a indicadores que combinen métricas cuantitativas con las cualitativas que reflejen los procesos de apropiación del conocimiento y el impacto social; denominadas métricas responsables, además de velar por la calidad de la gestión, y de políticas institucionales mesuradas que guían la valoración y evaluación de la actividad científica.


The scenario of new information and communication technologies has transformed the ways of evaluating scientific publication. Variety of instruments and indicators impact the evaluation processes. The objective of this work is to offer an assessment of the procedures used based on the use of knowledge. There is a need to advance in terms of indicators that combine quantitative metrics with qualitative ones that reflect the processes of knowledge appropriation and social impact; called responsible metrics, in addition to ensuring the quality of management, and measured institutional policies that guide the assessment and evaluation of scientific activity.

5.
Protein Sci ; 33(4): e4936, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38501461

RESUMEN

De novo designing immunoglobulin-like frameworks that allow for functional loop diversification shows great potential for crafting antibody-like scaffolds with fully customizable structures and functions. In this work, we combined de novo parametric design with deep-learning methods for protein structure prediction and design to explore the structural landscape of 7-stranded immunoglobulin domains. After screening folding of nearly 4 million designs, we have assembled a structurally diverse library of ~50,000 immunoglobulin domains with high-confidence AlphaFold2 predictions and structures diverging from naturally occurring ones. The designed dataset enabled us to identify structural requirements for the correct folding of immunoglobulin domains, shed light on ß-sheet-ß-sheet rotational preferences and how these are linked to functional properties. Our approach eliminates the need for preset loop conformations and opens the route to large-scale de novo design of immunoglobulin-like frameworks.


Asunto(s)
Anticuerpos , Pliegue de Proteína , Modelos Moleculares , Conformación Proteica en Lámina beta , Dominios de Inmunoglobulinas
6.
ACS Sustain Chem Eng ; 12(11): 4690-4699, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38516398

RESUMEN

In this work, the potential of a synthetic coculture and a mixed methanotrophic consortium to synthesize poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from renewable and waste-based feedstocks was assessed batchwise. Methylocystis parvuscocultivated with Rhodococcus opacus and a Methylocystis-enriched culture previously grown on methane were subjected to nutrient starvation in a medium enriched with valeric acid (30% w w-1 of Ctot) or with a VFAs mixture containing acetic, propionic, butyric, and valeric acids (15% w w-1 of Ctot) under a CH4:O2 or air atmosphere. For all test series, pH was adjusted to 7 after adding the cosubstrates, and a negligible substrate consumption or polymer production was considered the end point of the trial. Results showed that valeric acid promoted PHBV accumulation in both cultures regardless of the atmosphere. Interestingly, the mixture of VFAs supported PHBV accumulation only in the presence of methane. The highest PHBV contents for the coculture and the mixed consortium, equal to 73.7 ± 2.5% w w-1 and 49.6 ± 13% w w-1, respectively, were obtained with methane and the VFAs mixture. This study demonstrates the suitability of cocultures and biobased cosubstrates for the sustainable production of the biodegradable polymer PHBV.

7.
ACS Synth Biol ; 13(3): 862-875, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38357862

RESUMEN

Enzymes are indispensable biocatalysts for numerous industrial applications, yet stability, selectivity, and restricted substrate recognition present limitations for their use. Despite the importance of enzyme engineering in overcoming these limitations, success is often challenged by the intricate architecture of enzymes derived from natural sources. Recent advances in computational methods have enabled the de novo design of simplified scaffolds with specific functional sites. Such scaffolds may be advantageous as platforms for enzyme engineering. Here, we present a strategy for the de novo design of a simplified scaffold of an endo-α-N-acetylgalactosaminidase active site, a glycoside hydrolase from the GH101 enzyme family. Using a combination of trRosetta hallucination, iterative cycles of deep-learning-based structure prediction, and ProteinMPNN sequence design, we designed proteins with 290 amino acids incorporating the active site while reducing the molecular weight by over 100 kDa compared to the initial endo-α-N-acetylgalactosaminidase. Of 11 tested designs, six were expressed as soluble monomers, displaying similar or increased thermostabilities compared to the natural enzyme. Despite lacking detectable enzymatic activity, the experimentally determined crystal structures of a representative design closely matched the design with a root-mean-square deviation of 1.0 Å, with most catalytically important side chains within 2.0 Å. The results highlight the potential of scaffold hallucination in designing proteins that may serve as a foundation for subsequent enzyme engineering.


Asunto(s)
Proteínas Bacterianas , Glicósido Hidrolasas , Dominio Catalítico , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , alfa-N-Acetilgalactosaminidasa/química , alfa-N-Acetilgalactosaminidasa/metabolismo , Proteínas Bacterianas/metabolismo , Especificidad por Sustrato
8.
Rev. bras. parasitol. vet ; 33(2): e020523, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1565397

RESUMEN

Abstract Sarcoptic mange or scabies is a contagious parasitic skin disease that affects a wide range of domestic and wildlife species. A cross-sectional study was carried out to determine the prevalence, molecular identification, and characteristics of sarcoptic mange in vicuñas. A total of 3,274 vicuñas were examined. Following ritual harvesting events ("chaccus") in 13 Andean communities. The presence of mange mites was determined by the skin scraping technique and confirmed by PCR analysis using specific primers for the ITS2 gene of Sarcoptes scabiei. The presence of mange mites was also confirmed by microscopy using samples taken from wallows. A data collection form was used to register the characteristics of the vicuñas sampled. The prevalence of sarcoptic mange was 4.9% (95% CI: 4.1 - 5.6%). All samples from wallows tested positive (9/9). Importantly, the presence of the species S. scabiei was molecularly confirmed. Adult females with regular body condition were more susceptible to sarcoptic mange, although the lesions were mild. This study confirms the presence of S. scabiei in semi-captive vicuñas and points to the possible role of wallows in the dissemination of Sarcoptes mites.


Resumo A sarna sarcóptica é uma doença parasitária contagiosa da pele que afeta uma ampla gama de espécies domésticas e selvagens. Um estudo transversal foi realizado para determinar a prevalência, identificação molecular e características da sarna sarcóptica em vicunhas. Foram avaliadas 3.274 vicunhas, capturadas durante o "Chaccus", em 13 comunidades rurais alto andinas do Peru. A presença do ácaro da sarna foi determinada pelo raspado de pele e confirmada pela técnica de PCR, com iniciadores específicos para o gene ITS2 de Sarcoptes scabiei e por microscopia nos chafurdeiros. Foi preenchida uma ficha de coleta de dados com as características das vicunhas analisadas. A prevalência de sarna sarcóptica em vicunhas foi de 4,9% (95% IC: 4,1 - 5,6%). Todas as amostras de chafurda testadas (9/9) foram positivas, e a presença de S. scabiei foi confirmada molecularmente. Fêmeas adultas com condições corporais regulares foram mais suscetíveis à sarna sarcóptica, embora as lesões fossem leves. O estudo confirma a presença de S. scabiei em vicunhas em semicativeiro de comunidades camponesas alto andinas do Peru que sofrem de sarna. Destaca-se, ainda, o papel das chafurdas das vicunhas na disseminação da sarna.

9.
Nat Commun ; 14(1): 5939, 2023 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-37741853

RESUMEN

Antibody derivatives have sought to recapitulate the antigen binding properties of antibodies, but with improved biophysical attributes convenient for therapeutic, diagnostic and research applications. However, their success has been limited by the naturally occurring structure of the immunoglobulin dimer displaying hypervariable binding loops, which is hard to modify by traditional engineering approaches. Here, we devise geometrical principles for de novo designing single-chain immunoglobulin dimers, as a tunable two-domain architecture that optimizes biophysical properties through more favorable dimer interfaces. Guided by these principles, we computationally designed protein scaffolds that were hyperstable, structurally accurate and robust for accommodating multiple functional loops, both individually and in combination, as confirmed through biochemical assays and X-ray crystallography. We showcase the modularity of this architecture by deep-learning-based diversification, opening up the possibility for tailoring the number, positioning, and relative orientation of ligand-binding loops targeting one or two distal epitopes. Our results provide a route to custom-design robust protein scaffolds for harboring multiple functional loops.


Asunto(s)
Anticuerpos , Regiones Determinantes de Complementariedad , Bioensayo , Biofisica , Cristalografía por Rayos X , Polímeros
10.
J Chem Phys ; 158(6): 064110, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36792519

RESUMEN

Extended X-Ray Absorption Fine Structure (EXAFS) theoretical spectra for some 3d transition metal-phthalocyanines-FePc, NiPc, CuPc, and ZnPc-are presented. Their complexity and rigidity make them a good testbed for the development of theoretical strategies that can complement the difficulties present in the experimental spectrum fitting. Classical and ab initio molecular dynamics trajectories are generated and employed as a source of structural information to compute average spectra for each MPc species. The original ZnPc force field employed in the classical molecular dynamics simulations has been modified in order to improve the agreement with the experimental EXAFS spectrum, and the modification strategy-based on MP2 optimized structures-being extended to the rest of MPcs. Both types of trajectories, classical and ab initio, provide very similar results, showing in all cases the main features present in the experimental spectra despite the different simulation timescales employed. Spectroscopical information has been analyzed on the basis of shells and legs contributions, making possible the comparison with the experimental fitting approaches. According to the simulations results, the simple relationships employed in the fitting process to define the dependence of the Debye Waller factors associated with multiple scattering paths with those of single scattering paths are reasonable. However, a lack of multiple backscattering paths contributions is found due to the intrinsic rigidity of the chemical motif (macrocycle). Its consequences in the Debye Waller factors of the fitted contributions are discussed.

11.
Front Mol Biosci ; 9: 991380, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36275629

RESUMEN

Computational de novo protein design tailors proteins for target structures and oligomerisation states with high stability, which allows overcoming many limitations of natural proteins when redesigned for new functions. Despite significant advances in the field over the past decade, it remains challenging to predict sequences that will fold as stable monomers in solution or binders to a particular protein target; thereby requiring substantial experimental resources to identify proteins with the desired properties. To overcome this, here we leveraged the large amount of design data accumulated in the last decade, and the breakthrough in protein structure prediction from last year to investigate on improved ways of selecting promising designs before experimental testing. We collected de novo proteins from previous studies, 518 designed as monomers of different folds and 2112 as binders against the Botulinum neurotoxin, and analysed their structures with AlphaFold2, RoseTTAFold and fragment quality descriptors in combination with other properties related to surface interactions. These features showed high complementarity in rationalizing the experimental results, which allowed us to generate quite accurate machine learning models for predicting well-folded monomers and binders with a small set of descriptors. Cross-validating designs with varied orthogonal computational techniques should guide us for identifying design imperfections, rescuing designs and making more robust design selections before experimental testing.

12.
Nat Commun ; 13(1): 5661, 2022 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-36192397

RESUMEN

Antibodies, and antibody derivatives such as nanobodies, contain immunoglobulin-like (Ig) ß-sandwich scaffolds which anchor the hypervariable antigen-binding loops and constitute the largest growing class of drugs. Current engineering strategies for this class of compounds rely on naturally existing Ig frameworks, which can be hard to modify and have limitations in manufacturability, designability and range of action. Here, we develop design rules for the central feature of the Ig fold architecture-the non-local cross-ß structure connecting the two ß-sheets-and use these to design highly stable Ig domains de novo, confirm their structures through X-ray crystallography, and show they can correctly scaffold functional loops. Our approach opens the door to the design of antibody-like scaffolds with tailored structures and superior biophysical properties.


Asunto(s)
Anticuerpos de Dominio Único , Secuencia de Aminoácidos , Anticuerpos/química , Regiones Determinantes de Complementariedad , Dominios de Inmunoglobulinas , Modelos Moleculares , Conformación Proteica
13.
J Clin Med ; 11(15)2022 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-35956084

RESUMEN

BACKGROUND: Hip fracture in the elderly means that between a quarter and a half of patients do not regain the levels of independence and walking ability that they previously had, according to the literature, after the fracture. MATERIAL AND METHODS: Retrospective study of 537 patients aged ≥65 years who survived at the sixth month after fracturing their hip, of which the age, sex, type of fracture, surgical risk, independence (BI), walking ability, cognitive level (PS), comorbidities, indicated drugs, complications, surgical delay, hospital stay, and surgical technique are known. Using Pearson's χ2 test, all the variables were contrasted with respect to the limitation or not, at the sixth month of the recovery of both independence and pre-admission walking ability. Multivariate analysis provides the necessary adjustment to the previous contrast. RESULTS: We have found that age and PS ≥ 5 at admission limit recovery from both dependency and walking ability. Surgical risk, independence (BI) upon admission, anemia, and constipation during the hospital stay limit the recovery of the BI. Worsening of walking ability during the hospital stay and the type of extra-articular fracture, which was surgically treated by osteosynthesis, limit the recovery of walking ability. CONCLUSIONS: The factors previously exposed, and perhaps the fact that patients with hip fractures are not routinely referred to rehabilitation, explain the high proportion of patients who do not recover their previous independency (36%) or walking ability (45%) to the fact of fracturing.

14.
Inorg Chem ; 61(23): 8703-8714, 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35616567

RESUMEN

The physicochemical properties of the monovalent actinyl cations, PuO2+ and NpO2+, in water have been studied by means of classical molecular dynamic simulations. A specific set of cation-water intermolecular potentials based on ab initio potential energy surfaces has been built on the basis of the hydrated ion concept. The TIP4P water model was adopted. Given the paramagnetic character of these actinyls, the cation-water interaction energies were computed from highly correlated wave functions using the NEVPT2 method. It is shown that the multideterminantal character of the wave function has a relevant effect on the main distances of the hydrated molecular cations. Several structural, dynamical, and energetic properties of the aqueous solutions have been obtained and analyzed. Structural RDF analysis gives An-Oyl distances of 1.82 and 1.84 Å and An-O(water) distances of 2.51 and 2.53 Å for PuO2+ and NpO2+ in water, respectively. Experimental EXAFS spectra from dilute aqueous solutions of PuO2+ and NpO2+ are revisited and analyzed, assuming tetra- and pentahydration of the actinyl cations. Simulated EXAFS spectra have been computed from the snapshots of the MD simulations. Good agreement with the experimental information available is found. The global analysis leads us to conclude that both PuO2+ and NpO2+ cations in water are stable pentahydrated aqua ions.

15.
J Clin Med ; 11(9)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35566638

RESUMEN

(1) Background: Hip fracture is a pathology with high mortality, but the lack of a universal adaptation of the factors associated with death makes it difficult to predict risk and implement prevention in this group. This study aimed to identify the factors that determine a higher mortality at six months following hip fracture. (2) Methods: A retrospective longitudinal study, whose study population consisted of patients over 65 years of age. The main variable was mortality at 6 months of fracture. Relevant data related to sociodemographic and clinical variables for subsequent bivariate (χ2) and multivariate analysis were obtained. (3) Results: In all, 665 people participated in the study, 128 of whom died within 6 months of the fracture. The multivariate adjusted analysis demonstrated significant relationships between the main variable and aspects such as institutionalization at discharge (Odds Ratio (OR) = 2.501), a worse overall functional capacity (OR = 2.453) and cognitive capacity (OR = 3.040) at admission, and complications such as heart failure (OR = 5.767) or respiratory infection (OR = 5.308), in addition to the taking of certain drugs and the presence of a greater number of comorbidities. (4) Conclusions: There are certain factors related to higher mortality at six months in patients with hip fracture who are aged 65 years or older.

16.
J Clin Med ; 11(9)2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35566734

RESUMEN

BACKGROUND: cognitive impairment is known to be very common in patients with hip fractures, but studies are needed to help understand the relationship between both events. Our goal was to determine the relationship between moderate or severe cognitive impairment and hip fractures during the six months following that episode. METHODS: a retrospective longitudinal study was conducted on a sample of 665 people over 65 years of age. The main variable of the study was cognitive impairment at six months of fracture, assessed using the Pfeiffer scale (PS). Other data related to clinical features were also collected for further analysis. RESULTS: binary logistic regression analyses showed that the main factors related to moderate or severe cognitive impairment at the sixth month of the fracture were age (OR = 1.078), initial cognitive impairment (OR = 535.762), and discharge (OR = 547.91), cognitive worsening at the sixth month with respect to the time of admission (OR = 7.024), moderate dependence on admission (OR = 15.474) and at six months (OR = 8.088), poor ambulation at discharge (OR = 5.071) and institutionalization prior to admission (OR = 5.349) or during the first semester after fracture (OR = 6.317). CONCLUSIONS: this research provides evidence about the clinical factors that predict moderate or severe cognitive decline at the sixth month in patients undergoing surgery for a hip fracture.

17.
Comput Struct Biotechnol J ; 20: 534-544, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35465156

RESUMEN

Aureolysin, a secreted metallopeptidase (MP) from the thermolysin family, functions as a major virulence factor in Staphylococcus aureus. No specific aureolysin inhibitors have yet been described, making this an important target for the development of novel antimicrobial drugs in times of rampant antibiotic resistance. Although small-molecule inhibitors are currently more common in the clinic, therapeutic proteins and peptides (TPs) are favourable due to their high selectivity, which reduces off-target toxicity and allows dosage tuning. The greater wax moth Galleria mellonella produces a unique defensive protein known as the insect metallopeptidase inhibitor (IMPI), which selectively inhibits some thermolysins from pathogenic bacteria. We determined the ability of IMPI to inhibit aureolysin in vitro and used crystal structures to ascertain its mechanism of action. This revealed that IMPI uses the "standard mechanism", which has been poorly characterised for MPs in general. Accordingly, we designed a cohort of 12 single and multiple point mutants, the best of which (I57F) inhibited aureolysin with an estimated inhibition constant (K i) of 346 nM. Given that animals lack thermolysins, our strategy may facilitate the development of safe TPs against staphylococcal infections, including strains resistant to conventional antibiotics.

18.
Inorg Chem ; 60(17): 13578-13587, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34387993

RESUMEN

The physicochemical properties of the three heaviest alkaline-earth cations, Sr2+, Ba2+, and Ra2+ in water have been studied by means of classical molecular dynamics (MD) simulations. A specific set of cation-water intermolecular potentials based on ab initio potential energy surfaces has been built on the basis of the hydrated ion concept. The polarizable and flexible model of water MCDHO2 was adopted. The theoretical-experimental comparison of structural, dynamical, energetic, and spectroscopical properties of Sr2+ and Ba2+ aqueous solutions is satisfactory, which supports the methodology developed. This good behavior allows a reasonable reliability for the predicted Ra2+ physicochemical data not experimentally determined yet. Simulated extended X-ray absorption fine-structure (EXAFS) and X-ray absorption near-edge spectroscopy spectra have been computed from the snapshots of the MD simulations and compared with the experimental information available for Sr2+ and Ba2+. For the Ra2+ case, the Ra L3-edge EXAFS spectrum is proposed. Structural and dynamical properties of the aqua ions for the three cations have been obtained and analyzed. Along the [M(H2O)n]m+ series, the M-O distance for the first-hydration shell is 2.57, 2.81, and 2.93 Å for Sr2+, Ba2+, and Ra2+, respectively. The hydration number also increases when one is going down along the group: 8.1, 9.4, and 9.8 for Sr2+, Ba2+, and Ra2+, respectively. Whereas [Sr(H2O)8]2+ is a typical aqua ion with a well-defined structure, the Ba2+ and Ra2+ hydration provides a picture exhibiting an average between the ennea- and the deca-hydration. These results show a similar chemical behavior of Ba2+ and Ra2+ aqueous solutions and support experimental studies on the removal of Ra-226 of aquifers by different techniques, where Ra2+ is replaced by Ba2+. A comparison of the heavy alkaline ions, Rb+ and Cs+, with the heavy alkaline-earth ions is made.

19.
Rev. medica electron ; 43(3): 686-702, 2021. tab
Artículo en Español | LILACS, CUMED | ID: biblio-1289812

RESUMEN

RESUMEN Introducción: la depresión es uno de los problemas de salud que más afecta a los seres humanos a nivel mundial. En Cuba, un elevado número de personas padece este flagelo, sin distinción de razas, sexos u otras categorías. Objetivo: evaluar la efectividad de la hipnosis como modalidad terapéutica en pacientes deprimidos. Materiales y métodos: se realizó un estudio explicativo de tipo experimental de comparación de grupo pre-post prueba en 30 pacientes con trastornos depresivos; 15 de ellos se atendieron con hipnoterapia (grupo estudio) y otros 15 mediante terapia racional emotiva conductual (grupo control). Por la importancia para enriquecer la investigación, se definió como variable independiente el tratamiento empleado según el grupo, y como variables dependientes la respuesta psicológica antidepresiva y ansiolítica. Los datos se procesaron cuantitativa y cualitativamente. Se empleó la prueba de las probabilidades exactas de Fisher y la t de Student para validar la significación del cambio. Resultados: en términos de evolución clínica, la hipnoterapia fue efectiva, ya que el 93,3 % de los pacientes mejoraron significativamente en comparación con los resultados obtenidos con la terapia conductual racional emotiva, dados en un 73,33 %. Conclusión: la hipnoterapia es tan efectiva como la terapia racional emotiva conductual, y si bien no hubo diferencias significativas por los resultados del estadígrafo matemático empleado, sí las hubo desde el punto de vista práctico y clínico, pues evolucionaron más rápido los pacientes del grupo estudio que los del grupo control (AU).


ABSTRACT Introduction: depression is one of the health problems more affecting the human being around the world. A high number of persons suffers this scourge, without distinction of race, sex or any other category. Objective: to assess hypnosis effectiveness as a therapeutic modality in depressed patients. Materials and methods: an experimental-kind explanatory study was carried out comparing a group of 30 patients with depressive disorders before and after test; 15 of them were treated with hypnotherapy (study group) and 15 with rational emotive behavioral therapy (control group). For the importance of enriching the research the treatment used according to each group was defined as independent variable and the anxiolytic and anti-depressive psychological answer. Data were quantitative and qualitatively processed. Fisher's exact test and T student test were used to validate the change significance. Results: in terms of clinical evolution, hypnotherapy was effective, since 93.3% of patients significantly improved in comparison to the results achieved with the rational emotive behavioral therapy, reaching 73.33%. Conclusions: hypnotherapy is as effective as rational emotive behavioral therapy, and although there were not significant differences due to the results of the used mathematical statistic, there they were from the practical and clinical point of view, because the patients from the study group improved faster than the ones in the control group AU).


Asunto(s)
Humanos , Masculino , Femenino , Depresión/terapia , Hipnosis/métodos , Pacientes/psicología , Terapéutica/métodos , Servicios de Salud/normas
20.
Salud Publica Mex ; 63(2, Mar-Abr): 160-162, 2021 Feb 27.
Artículo en Español | MEDLINE | ID: mdl-33989476

RESUMEN

OBJECTIVE: To describe a Covid-19 outbreak in a gerontological center in Mexico City. MATERIAL AND METHODS: Cross-sectional study in older adults. The association of risk factors for dying from Covid-19 was analyzed using a multiple logistic regression model. RESULTS: One hundred and two elders with an average age of 82.5 ± 8.8 years were included. Fifty-five (54%) tested positive and 47 (46%) were negative for the new coronavirus. Using the multiple logistic regression model, people with frailty had an OR of 11.6 of dying from Covid-19 compared to robust people (p-value = 0.024). CONCLUSION: The Covid-19 outbreak was initially caused by a resident of the center and spread by cross infection. In vulnerable populations, early detection, isolation, and follow-up of contacts should be carried out, as well as the identification of risk factors in order to reduce the spread and mortality caused by SARSCoV-2.


Asunto(s)
COVID-19/epidemiología , Brotes de Enfermedades , Hogares para Ancianos , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , México
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