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

Introduction. Actinoporins (AP) are pore-forming proteins (PFPs) that readily bind to membranes leading to cell death. Sticholysins I and II (St, StI/II) are among the most potent AP described in nature. This proposal aimed to characterize the influence of lipid composition and dynamic properties of membranes on binding and pore-formation by StI/II and nigrelysin (Ngr), a novel AP here described. Methods. Binding and pore-formation were studied using model membranes such as liposomes and lipidic monolayers combined with fluorescence spectroscopy and microscopic techniques.Results and Discussion. St and Ngr bind and preferentially permeabilize membranes containing sphingomyelin (SM) over phosphatidylcholine (PC). This is explained by the presence of the PC phosphocholine unit plus a ceramide moiety (Cer) in SM. StI also recognizes Cer and gangliosides although to a lesser extent. In terms of dynamic properties, StI penetrates preferentially membranes with high lateral mobility and moderately enriched in SM. Also, StI permeabilizes more efficiently membranes containing sterols, in addition to SM. The appearance of borders resulting from lipidic domains coexistence is not a determining factor for binding or activity in membranes. Indeed, the activity is enhanced by membrane molecular heterogeneity beyond the presence of lipidic domains. As a conclusion these studies explain the relevance of SM and sterols for St, Ngr, and by extension, to APs binding to membrane and explain the contribution of other Cer-based lipids to their activity. In dynamic terms, a highly fluid phase, and moderately enriched in SM and sterols, is an ideal platform for the formation of pores in the membrane for AP.

Introduction. This work presents the research results obtained from the detection of orange rust in Cuba. With the objectives of to detect the presence of Puccinia kuehnii (W. Kruger) E. J. Butler; to evaluate the severity of the disease; to characterize the symptoms and response of cultivars to the pathogen; to determine a favorable time of the year for its development; to update its distribution in the country. Methods. Phytosanitary evaluations and diagnosis were carried out using optical microscopy and Real Time PCR, in commercial plantations, seed areas and experimental stations. Results. P. kuehnii was detected and reported for the first time in 2008. The highest severity was observed in CSR81-86, CSG398-92 and B52107, less in the positive controls CP72-2086 and Q124. Significant variations were observed between infected cultivars and that leaf +3 can be used in the severity evaluation. C01-227 was used as a susceptibility control and a protocol was elaborated to select resistant cultivars; the reaction of eight commercial cultivars was determined. P. kuehnii was detected in all the provinces; the highest number of infected genotypes is found in the areas of the experimental stations, mainly in Mayabeque, Villa Clara and Camagüey. As some conclusions the distribution of orange rust is classified as low prevalence. The results of the phytosanitary surveillance indicate that some of the main commercial cultivars are susceptible and confirm the potential danger of this disease, which is more severe in the plantations carried out from April to September.

Objectives: The primary aim of this work is to study the immunological effectors induced in CIGB-247-vaccinated patients. These effectors include humoral and cellular components of the immune system. Also, the goal of the present investigation is to detect different immunoglobulin classes and subclasses and its specificity for VEGF relevant epitopes, and demonstrate the induction of VEGF-specific and cytotoxic CD8 T lymphocytes. This research has, as an additional objective, the presentation of the first preliminary pieces of evidence of the feasibility to combine CIGB-247 with other anti-cancer treatments. To investigate the vaccine-induced immunological effectors, ELISA and ELISPOT tests were used for monitoring the immune response elicited in cancer patients from the CENTAURO and CENTAURO-2 clinical trials and also those from the compassionate use program. Results. Immunization with CIGB-247 elicited VEGF-specific IgM and IgA antibodies. Antibody response maturation was detected in some patients with long term overall survival, indicated by the subclass switching from IgG1 to IgG4. This antibody response blocked the interaction of VEGF with its receptors VEGFR2 and VEGFR1. This specific polyclonal antibody response inhibited the binding between VEGF and the monoclonal antibody bevacizumab, for that reason, it was directed to a relevant epitope on VEGF, implicated in the VEGF-induced proangiogenic activity. The vaccination contributed to normalizing platelet VEGF levels, and produced cytotoxic CD8 T lymphocytes. Some experimental evidence indicated the potential use of CIGB-247 in combination with chemotherapy. Conclusions: All these results allowed for the application of CIGB-247 in phase II clinical trials in combination with other cancer therapeutic treatments.

Introduction. Contamination by persistent organic compounds (POCs) and heavy metals in waters and soils is a serious environmental problem. Objectives: To evaluate the use of microorganisms (autochthonous and from collection) and their products, in the removal of these contaminants. Methods. Autochthonous microorganisms were isolated by sequential enrichment. The quantification of rhamnolipids and chlorophenols was performed by colorimetric methods and hydrocarbon removal was gravimetrically quantified. Metals were determined by plasma atomic absorption (AAS-ICP). Results. Rhamnolipid produced by Pseudomonas aeruginosa ORA9 removed more than 50 % of copper present in waters and 75 % of hydrocarbons from contaminated soils. Likewise, the use of 4 bacterial strains and rhizospheric bacteria isolated from contaminated soils allowed up to 84 % and 72 % of hydrocarbon removal and degradation of herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), respectively. On the other hand, the effectiveness of using biological systems for the treatment of hydrocarbon and heavy metal contaminated waters was verified, obtaining percentages of hydrocarbon removal of 60 % and 84 % with a designed airlift bioreactor and an aerobic/anaerobic reactor system, respectively. Finally, using dry microbial biomass, 52 %, 23 % and 14 % of copper, zinc and manganese metals, respectively, present in contaminated waters were extracted. Conclusions: The results of this research constitute the scientific bases to implement a technological package for the remediation of sites contaminated with POCs and heavy metals using microorganisms.

Introduction. The aim of the research was to use nanoparticles of clays, calcium phosphate salts and ceramics, combined with fluorogenic and chromogenic substrates to significantly shorten the period of microbiological diagnosis. Methods. Combinations of nutritional bases, co-enzymes, co-factors that accelerate microbial development and metabolism were selected. These components were coupled with nanoparticles and fluorogenic and chromogenic substrates to obtain different nanocomposites. Nanoparticles and nanocomposites were characterized according to their composition, structure and functionality both with isolated strains of microorganisms, and in clinical samples, water, among others. Results. Nanoparticles and aggregates of halosites, bentonites, siliceous earth, hydroxyapatites, calcium phosphates and zeolites showed high surface / volume ratio, porosity and surface roughness, with particle and pore sizes in the nanometric order. Protein extracts and hydrolysates were combined with a set of salts and co-enzymes that enabled rapid cell multiplication and the synthesis of microbial enzymes detected in just minutes by the degradation of a combination of fluorogenic and chromogenic substrates. The nanoparticles and aggregates were coupled with the other components obtaining different structures that allowed for reducing the incubation time for detection, identification, isolation and counting to a minimum of 10 to 60 min in direct samples. As a conclusion, a rapid diagnosis platform for microorganisms was achieved using nanoparticles and aggregates of clays and ceramics coupled with substrates that reveal enzymatic activity in only minutes.

Introduction. Cuba has 20,8 % of its population with 60 years or more, a number relatively homogeneous in all its territories, with an increasing tendency in the course of time and in the perspective. This research constitutes the baseline for the first longitudinal study in older people in Cuba. Its objective is updating and completing the informative and scientific base about the characteristics and evolution of the aging process of the Cuban population, by considering the study of aspects such as demographic characteristics, socioeconomic conditions, state of health, of residence, among other aspects, regarding people of 50 years and more, with a particular insight toward the old and very old population. Besides, the study seeks creating suitable methodological conditions that allow for establishing the baseline for a follow-up and evaluating in time the aging process of people that today are 50 years old and more and, in the near future, will make up the senescent population of the country. Methods. The study covered the entire country. A sample design was carried out for a longitudinal study, with a probabilistic sampling by Stratified Three-Stage Conglomerates. The information was obtained by direct interview and the data collected was validated. Results. The median age is 62 years and the female index was 1,144, increasing with age and in urban areas, where 78,6 % of the Cuban elderly live. Almost half of the people are single, and men receive more income than women do. Most people perceive their health as fair or poor, and more than half suffer from at least two chronic diseases. Almost half of people aged 60 to 74 are robust, but frailty and pre-frailty increase with age and in women. The majority of older people are independent, although dependency increases with age and in women. The group of 75 years and over barely exceeds 50 % in physical activities, especially women. At any age, men are more involved in volunteer activities. The aid they receive does not vary significantly according to age. By sex, it is observed that women perceive this aid in a higher proportion than men do. Both men and women receive more help with increasing age and less help from older people. As some conclusions at any age, women are more likely to succumb to diseases, perceive their health as poor, and be dependent. This gender gap must be taken into account in public policies on aging. Society could benefit more from the help that older people provide. The possibility of identifying the people who are at greater risk of being affected by an adverse event allows for greater equity and efficiency of actions to be achieved, prolonging independence and well-being.

Introduction. Based on research initiated during 1986, which constitutes the baseline information, the resilience capacity of the Red Ferrallitic soils in the southern Karstic plain Havana-Matanzas is demonstrated for the first time, as a result of a multifactorial process, conditioned not only by the intrinsic properties of the soil cover and conditions of use, but also dependent on the geological-geomorphological conditions. Methods. The C1 profile (without apparent erosion), located in an area in biostasis, was used as a baseline to evaluate the magnitude of loss of Red Ferrallitic soils through Karst depressions in different scenarios using the prediction model of Kay et al. (1994). Results. It was concluded that under normal agricultural practices the Red Ferrallitic soils affected by erosion would recover in a period of 50 years, while according to the degree of limestone impurities it would take between 100 to 600 years. It was recommended to the authorities that it was necessary to definitively apply the results obtained for more than three decades in the determination of the specific modalities assumed by the degradation of the Red Ferrallitic soils, so that their degradation ceases to be a myth and becomes a priority issue for the food sovereignty and nutritional education plan of Cuba post-COVID-19, since they represent the maximum potential to satisfy what the country currently demands for agricultural productions.

Introduction. n-Butyl cyanoacrylate (BCA) and its polymer, poly (n-butyl cyanoacrylate) (PBCA) have excellent adhesive, biocompatible and biodegradable properties for medical applications. The current work presents new methods for producing BCA of high purity and PBCA micro/nanofibers as potencial pharmaceutic products. Methods. Microwave radiation was used for producing BCA, and electro-spinning technique for PBCA micro/nanofibers, whose physical chemistry, mechanical, biological and drug delivery properties were evaluated. Results. The process time for BCA production was reduced by a factor from 3 to 5 fold when microwave radiation was used respecting oil bath. The application of electro-spinning to solutions of PBCA with different molecular weights produced fibers free of defects with diameters between 400 nm and 5 mm. Young´s modulus and maximal tension values were determined in the range from 0,7 MPa to 1,9 MPa and 0,05 MPa to 0,12 MPa respectively. The thermal degradation of PBCA nanofibers and those charged with 15% of 5-fluorouracil was 110 oC to 241oC and 100 oC to 309 oC, with the corresponding maximal peaks at 186 oC and 203 oC. The cytostatic 5-fluorouracil was homogeneously loaded inside PBCA fibers, with a release of 20 % in 7 days and the rest gradually (until 96 days) in physiological medium. Human fibroblasts proliferated over PBCA nanofibers. As a conclusion: Microwave radiation reduces the reaction time for BCA synthesis in a significant way. The electro-spinning of PBCA produces meshes based on micro/nanofibers, which can be used as drug delivery and tissue engineering systems.

Introduction. We developed and implemented novel methods for the computer simulation of ultrafast quantum dynamics in molecular systems, which were subsequently applied in the investigation of a wide variety of photoinduced dynamical processes in atoms, molecules and solids. Methods. The new methodology maps the dynamics of the original quantum system into that of an equivalent classical system with larger dimensionality. The resulting equations of motion were integrated numerically using algorithms with adaptive time step. The computed observables were compared with the results obtained via wavepacket propagation. Results and discussion. The methodology reproduces paradigmatic quantum effects such as zero-point energy, tunnel effect and quantum interference; its accuracy and numerical efficiency surpasses those of alternative computational tools available nowadays. It accounts correctly for phenomena as diverse as the photoionization of an atom by an ultrashort laser pulse, the vibrational predissociation of van der Waals complexes, the electron dynamics in quantum dots and the photoexcitation of alkali metal atoms in rare gas matrices. Conclusions. It was concluded that the simulation of the quantum dynamics of atoms, molecules and solids has shown that the predictions of the interacting trajectory propagation scheme are in excellent agreement with the observables calculated from the direct solution of the Schrödinger equation, and with the available experimental data. Additionally, the method provides an intuitive representation of the dynamical processes, since the trajectories follow the flux lines of the quantum probability density.

Introduction. Interprofessional Education since its emergence in the seventeenth century to the present, has been climbing ever higher levels that place it on a par with the most visible and legitimate achievements of the Cuban revolutionary process, above all because of its marked social and humanitarian character. It is conceived as occasions when 2 or more professions learn with each other and about others to improve collaboration and quality of care and services. The objective is to contribute, from theory and practice to interprofessional education from the contributions sustained in the socio-historical-cultural school of Vigotsky and its followers and the most innovative approaches in the treatment of people with disabilities. Methods. The materialist-dialectical philosophy, its laws and categories, which constitute the fundamentals for this paper. Another aspect is the theory of knowledge, the understanding of the transition from clear perception to a qualitatively higher practice after a process of intellectual elaboration. Results and Discussion. In three phases of research, 18 proposals were brought forward, both methodological models and pedagogical strategies, which were introduced in professional practice and had an impact on the quality of teaching students with special educational needs.