Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

(letter to editor)

Speech given by Dr. Luis Velázquez Pérez, on July 13, 2022

Introduction. Intralesional infiltration of epidermal growth factor (EGF) has emerged as a therapeutic alternative for diabetic foot ulcer (DFU) healing. The objectives of this research were: to determine the molecular profile of patients with DFU and to characterize the systemic effects of EGF intralesional treatment in such patients, taking into account redox balance markers, components of the advanced glycation end-product (AGE) pathway, factors related to the extracellular matrix (ECM) stability and pro-inflammatory markers. Methods. Thirteen patients with DFU were characterized in comparison with diabetic patients without ulcers (compensated and non-compensated) and non-diabetic subjects, attending to redox balance markers, components of the AGE pathway, and elements related to the stability of the ECM. The systemic response of patients with DFU to the intralesional treatment with EGF was evaluated according to the same parameters, in addition to other pro-inflammatory markers. Results. Patients with DFU exhibited the most disheveled biochemical profile, with elevated oxidative stress, low antioxidant reserves, increased glycoxidation products and matrix metalloproteases (MMP), with respect to non-ulcerated diabetic patients and to non-diabetic subjects. The intralesional administration of EGF was associated with a significant recovery of the parameters studied and with the systemic attenuation of several pro-inflammatory markers. Conclusions: These results indicate that intralesional infiltration of EGF translates into systemic antioxidant, anti-inflammatory, anti-degradative and anti-AGE effects, which contribute to restoring homeostasis in the diabetic patient.

Introduction. This paper deals with one result of the research project Education for citizen life in the educational formation and school, form the contributions of Martí and Fidel (2018-2020), focusing in the concept of Education for citizen life, introduced in the present improving of the National System of Education, as an expression of the Martí concept that Educating is to prepare man for life. The objective was to evaluate the importance of education for citizen life in the Cuban educational context. Methods. The dialectical materialist conception of scientific knowledge contributes the general methodology for the study and transformation of reality; in this case, in the area of social sciences and humanities, and the field of pedagogy as a science for the integral education of personality and the core of education sciences. The logical-historical method was used to highlight the main aspects of the object of study. The synthetic-analytical method was used to study the components and factors involved in this complex formation process. The document analysis and observation were also used. Results and discussion. This study facilitated the systematization of the fundamentals of a pedagogical conception on citizen formation for pedagogical majors, as well as the distinctive aspects of this formation process and their insertion in the curriculum of the Study Program E, as a contribution to improving higher education, for pedagogical majors in this case. This enriches the training of professors majoring in Marxism-Leninism and History for junior and senior high school who teach the subjects of Moral and Citizen Education, Political Culture, and the Ideological Fundamentals of the Cuban Revolution and Socialism Construction.

Introduction. Inside the high vacuum chambers of the plasma heater of the future nuclear fusion reactors, such as ITER or DEMO, so-called “dark currents” are produced which, with time, cause damages to different components. Although this typical emission has an explanation on the basis of field emission theory, there are still many questions to be described. The objective was to use a model based on Density Functional Theory to describe some aspects of the field emission due to contaminated surfaces or nanometric irregularities. Methods. Studies were conducted on tungsten and tungsten carbide surfaces contaminated with carbon, as well as on clean tungsten corrugated surfaces. Results. Knowledge of the origin of “dark currents” was advanced, as well as its relation with different irregularities on the cathode surfaces.

Introduction: Natural sorbents have been widely used in environmental studies for decades. These materials can be used to develop analytical procedures to monitor and/or remove toxic metals from waters. Among the heavy metals most used in industry and therefore frequently found in water, are Pb, Cd and Ni with high harmful effects on human health, even at relatively low concentrations in the order of parts per million. On the other hand, some of Platinum salts are used in the pharmaceutical industry and other industrial processes that generate toxic waste. Two natural Cuban sorbents are used in this research, the inactive biomass of the Aspergillus niger O5 fungus and the purified NZ zeolite from Tasajeras deposit, with and without chemical treatments. The purpose has been to characterize these materials as sorbents to develop analytical procedures for preconcentration / removal of Pb (II), Ni (II), Cd (II) and Pt (IV) in drinking water. Methods: The determination of metals during the sorption studies was carried out in the liquid and solid phases indistinctly. The AAS with flame, UV-Vis spectrophotometry, XRF and PIXE techniques were used. The chemical-physical characterization of sorbents was also carried out with modern techniques (SEM-EDS; IR; XRD, XPS, RBS, ERDA), which contributed to suggesting mechanisms of metal-sorbent interaction. Results: The maximum sorption capacity values of sorbents were: Lead: 8.6 and 75 mg·g-1 in biomass treated with HCl and zeolite treated with NH3, respectively; Platinum: 80 mg·g-1 in biomass treated with CTAB; Nickel: 28 mg·g-1 in zeolite treated with NaOH and Cadmium: 66 mg·g-1 in untreated zeolite. Conclusions: Theses results confirm the high potentiality of the studied sorbents for the preconcentration / removal of Pb (II), Ni (II), Cd (II) and Pt (IV) from drinking water.

Introduction. The World Health Organization (WHO) recommends conducting nationally representative studies to estimate the prevalence of HIV pretreatment resistance to antiretrovirals (PDRs) to assess the effectiveness of first-line therapies. The objective of the present study was to determine the prevalence of PDR in Cuban adults infected with HIV-1. Methods. HIV resistance to antiretrovirals was determined in 610 Cuban patients in two time periods (469 patients between 2009-2016 and 141 patients during the national survey of HIV-1 PDR conducted during 2017, according to the recommendations issued by the WHO). Results and Discussion. In the period 2009-2016, 19% of the patients presented viruses with some mutation associated with the PDR of HIV-1 to antiretrovirals (10,4 % to some nucleoside reverse transcriptase inhibitor (NRTI), 12,8 % to some non nucleoside reverse transcriptase inhibitor (NNRTI), 2,8 % to some protease inhibitor (PI). In 2017, the prevalence of PDR was 29,8 % (95 %, CI 22,3-38.1). The prevalence was 10,6 % (95 %, IC 6,07-16,9) for some NRTI, 23,4 % (95 %, CI 16,7-31,3) for some NNRTI, and 1,4 % (95 %, CI 0,17-5,03) for some PI. It was concluded that the NNRTI prevalence above 10 % in our study indicates that the first-line antiretroviral therapy in Cuba may be less effective and supports the need to look for new treatment options.

Introduction. Ticks are ectoparasites, which are vectors of infectious diseases for humans and animals. Vaccination could be an ecological alternative to chemicals to control these ectoparasites. A peptide of the ribosomal protein P0 conjugated to hemocyanin from the mollusk Megathura crenulata (KLH) has shown an effectiveness of more than 90 % against Rhipicephalus sanguineus and R. microplus tick species. However, KLH is an expensive protein that is not an economically viable alternative for developing this peptide as a commercial vaccine. Methods. The synthetic P0 peptide was chemically conjugated to the Bm86 protein obtained by fermentation of a recombinant Pichia pastoris yeast. This conjugate was characterized by SDS-PAGE analysis and mass spectrometry and was used in immunization and challenge experiments against different tick species. Results. SDS-PAGE analysis of this conjugate showed that it is very heterogeneous and that there are from 1 to 18 molecules of pP0 per molecule of Bm86. LC-MS/MS analysis and the combination of 4 different software showed that 49 of the 54 lysine residues and the N-terminal end of the Bm86 protein were partially conjugated to pP0. This conjugate pP0-Bm86 generated an immune response against the peptide when used as an antigen in immunization experiments of different animals. This immune response affected the viability and reproductive potential of different tick species. Conclusion, these results demonstrate that the P0 peptide is a broad spectrum antigen and permit its development as an anti-tick vaccine.

Introducción. El perfeccionamiento de la gestión universitaria constituye un aspecto prioritario y actual para la educación superior cubana. Este reto refuerza la importancia de producir transformaciones frente a un entorno complejo en lo económico, sociopolítico, cultural y ambiental. Es en este contexto donde resalta el papel de la extensión universitaria como una importante función social y un proceso formativo integrador de los vínculos universidad-sociedad. El objetivo del estudio se centró en la elaboración de una metodología para el perfeccionamiento del proceso de planeación estratégica de la actividad extensionista en la universidad médica matancera. Métodos. Se aplicó un enfoque metodológico cualitativo y de investigación-acción. Se presentó sobre la base del diagnóstico realizado, una planeación estratégica que consideró a dicho proceso como parte de la estrategia maestra principal, la cual impactó en todas las áreas universitarias, en correspondencia con el horizonte temporal 2017-2020. Resultados. Se modeló una metodología a partir de la cual se obtuvo una estrategia extensionista, cuyas acciones fueron integradas al sistema de trabajo, a la planeación estratégica. Se perfeccionó el Gobierno universitario, tributando al cumplimiento de la misión y visión de la institución. Se proporcionó un marco referencial que introdujo una transformación sin precedentes en cuanto a su esencia y proyección social. Conclusiones. Se evidenció un salto cualitativo en la gestión de la calidad universitaria, a la vez que denotó la necesidad de proseguir las investigaciones científicas y profundizar en la planificación estratégica extensionista, como importante función y proceso pedagógico universitario de carácter complejo.

The analysis of the gait and posture is useful for the study of hereditary ataxias. The clinical test does not offer objective information of alterations of its parameters. Instrumental methods provide quantitative measures to describe progress disorders and posture. The main instrumental methods used are the movement capture videographic, the pressure sensitive gateway system GaitRite and the inertial sensor system APDM Mobility Lab. The most reported alterations in patients with ataxia are decreased cadence; stride length, gait speed, increase in double support of lower limb, length and acceleration of postural sway. The most advantageous method is the system of inertial sensors. The alterations detected with instrumental methods provide valuable information in the early detection of ataxias, their progression and to measure the response to therapeutic interventions.