[Thematic analysis of Primary Care journals indexed in Journal Citation Reports: 2015-2019]. / Análisis temático de las revistas de Atención Primaria indexadas en Journal Citation Reports: 2015-2019.

OBJECTIVE: Analyze the thematic lines of the articles and reviews published between 2015 and 2019 in the journals indexed in the "Primary Health Care" category of the Journal Citation Reports. METHODS: Observational bibliometric study. The bibliographic records of the Web of Science were identified and the frequencies of appearance of the thematic descriptors and their co-occurrence in the documents included in the study were analyzed. In addition to the global analysis, the reviews, the most cited documents, those published in 2015, and those published in 2019 were analyzed separately. Descriptors were classified by thematic clusters using the Current Canadian Index scale and clinical publications were analyzed using the second edition of the International Classification of Primary Care. RESULTS: A total of 16,444 descriptors were identified in the 7,453 documents analyzed. The most frequent descriptors focus on: diagnosis, prevalence, management, risks, care practice and the figure of the health professional. In the most cited documents, terms with specific themes were used: depression, intervention, satisfaction, quality, therapy, research-based practice. In 2019, there were a greater number of publications focused on epidemiology, clinic, research and provision of services. From a clinical point of view, studies on psychological and mental health problems, nervous system, social problems, palliative care and cancer increased in 2019. CONCLUSIONS: The analysis carried out identifies the relevant thematic lines in primary care journals, highlighting the diagnosis and prevalence of diseases, the management of pathologies and their associated risks, as well as clinical practice and the figure of the health professional.

Reply to the 'Comment on "Methanol dimer formation drastically enhances hydrogen abstraction from methanol by OH at low temperature"' by D. Heard, R. Shannon, J. Gomez Martin, R. Caravan, M. Blitz, J. Plane, M. Antiñolo, M. Agundez, E. Jimenez, B. Ballesteros, A. Canosa, G. El Dib, J. Albaladejo and J. Cernicharo, Phys. Chem. Chem. Phys., 2018, 20, DOI: 10.1039/C7CP04561A.

In this Reply we answer the two main arguments raised in the Comment. The first argument is related to the binding energy of the methanol dimer and its influence on the dimerization rate constant. We show that the dimerization rate constants calculated in the Comment are unphysically low. We report values that are about two orders of magnitude higher than the values of the Comment, which confirm the conclusions of the original article that dimers can be present in a small amount. The second argument based on the dependence of the pseudo-first order rates on the methanol concentration was already explained in detail in the Supporting Information of the original article.

Theoretical kinetics study of the F((2)P) + NH3 hydrogen abstraction reaction.

The hydrogen abstraction reaction of fluorine with ammonia represents a true chemical challenge because it is very fast, is followed by secondary abstraction reactions, which are also extremely fast, and presents an experimental/theoretical controversy about rate coefficients. Using a previously developed full-dimensional analytical potential energy surface, we found that the F + NH3 → HF + NH2 system is a barrierless reaction with intermediate complexes in the entry and exit channels. In order to understand the reactivity of the title reaction, thermal rate coefficidents were calculated using two approaches: ring polymer molecular dynamics and quasi-classical trajectory calculations, and these were compared with available experimental data for the common temperature range 276-327 K. The theoretical results obtained show behavior practically independent of temperature, reproducing Walther-Wagner's experiment, but in contrast with Persky's more recent experiment. However, quantitatively, our results are 1 order of magnitude larger than those of Walther-Wagner and reasonably agree with the Persky at the lowest temperature, questioning so Walther-Wagner's older data. At present, the reason for this discrepancy is not clear, although we point out some possible reasons in the light of current theoretical calculations.

Assessment of cellular and plasma oxidative stress in SAHS patients before and after continuous positive airway pressure treatment.

BACKGROUND: Several indirect techniques have been used for measuring oxidative stress in sleep apnoea-hypopnoea syndrome (SAHS) patients. The purpose of this study was to find out if both, cellular or plasma oxidative stress evaluations, are good estimators to assess oxidative stress in SAHS patients before and after one month's CPAP treatment. METHODS: The study included 28 SAHS patients requiring CPAP treatment and 15 healthy control subjects. Plasma and serum oxidative stress biomarkers (lipid peroxidation, total antioxidant capacity, and the activities of glutathione peroxidase, glutathione reductase, glutathione s-transferase, catalase and superoxide dismutase) were measured using commercial kits. Cellular oxidative stress biomarkers (mitochondrial membrane potential, intracellular glutathione, superoxide anion, and hydrogen peroxide) were analysed by flow cytometry. The Wilcoxon test for paired samples was used to compare oxidative stress and clinical parameters in patients before and after treatment with CPAP. Relationships in oxidative stress markers between controls and patients were analyzed using the Mann-Whitney U test. The Spearman correlation coefficient was calculated to estimate the linear correlations between variables. RESULTS: Oxidative stress was notably decreased after CPAP. Before CPAP, SAHS severity positively correlated with hydrogen peroxide levels, while negative correlations were observed between SAHS severity and plasma TAC in patients. Also, plasma glutathione peroxidase activity negatively correlated with cellular superoxide anion, while plasma superoxide dismutase activity positively correlated with intracellular glutathione. After CPAP, plasma TAC and glutathione peroxidase activity negatively correlated with cellular hydrogen peroxide and superoxide anion. CONCLUSIONS: In conclusion, this study seems to confirm that plasma and cellular assessment reflect, in the same way, the oxidative stress status of the studied patients. Furthermore, plasma total antioxidant capacity as well as cellular hydrogen peroxide levels can be good markers for assessing oxidative stress in SAHS patients.

Quasiclassical trajectory study of the F + CH4 reaction dynamics on a dual-level interpolated potential energy surface.

An ab initio interpolated potential energy surface (PES) for the F + CH4 reactive system has been constructed using the interpolation method of Collins and co-workers. The ab initio calculations have been performed using second-order Möller-Plesset (MP2) perturbation theory to build the initial PES. Scaling all correlation (SAC) methodology has been employed to improve the ab initio calculations and to construct a dual-level PES. Using this PES, a detailed quasiclassical trajectory study of integral and differential cross sections, product rovibrational populations and internal energy distributions has been carried out for the F + CH4 and F + CD4 reactions and the theoretical results have been compared with the available experimental data.

Trajectory dynamics study of the Ar + CH4 dissociation reaction at high temperatures: the importance of zero-point-energy effects.

Large-scale classical trajectory calculations have been performed to study the reaction Ar + CH4--> CH3 +H + Ar in the temperature range 2500 < or = T/K < or = 4500. The potential energy surface used for ArCH4 is the sum of the nonbonding pairwise potentials of Hase and collaborators (J. Chem. Phys. 2001, 114, 535) that models the intermolecular interaction and the CH4 intramolecular potential of Duchovic et al. (J. Phys. Chem. 1984, 88, 1339), which has been modified to account for the H-H repulsion at small bending angles. The thermal rate coefficient has been calculated, and the zero-point energy (ZPE) of the CH3 product molecule has been taken into account in the analysis of the results; also, two approaches have been applied for discarding predissociative trajectories. In both cases, good agreement is observed between the experimental and trajectory results after imposing the ZPE of CH3. The energy-transfer parameters have also been obtained from trajectory calculations and compared with available values estimated from experiment using the master equation formalism; in general, the agreement is good.

A quantum-dynamics study of the prototropic tautomerism of guanine and its contribution to spontaneous point mutations in Escherichia coli.

High-level quantum-chemical and quantum-dynamics calculations are reported on the tautomerization equilibrium and rate constants of guanine and its complexes with one and two water molecules. The results are used to estimate the fraction of guanine present in the cell during DNA synthesis as the unwanted tautomer that forms an irregular base pair with thymine, thus giving rise to a spontaneous GC --> AT point mutation. A comparison of the estimated mutation frequency with the observed frequency in Escherichia coli is used to analyze two proposed mechanisms, differing in the extent of equilibration reached in the tautomerization reaction. In the absence of water, the equilibrium concentration of tautomeric forms is relatively large, but the barrier to their formation is high. If water is present, tautomeric forms are less favored, but water molecules may serve as efficient proton conduits causing rapid tautomerization. It is tentatively concluded that the mechanism in which a high tautomerization barrier keeps the tautomeric transformation far from a state of equilibrium is more likely than a mechanism in which water and/or polymerases produce a low equilibrium concentration of the tautomeric forms.