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In Cuba, the first pacemaker implant was carried out on July 6, 1964, while in Cienfuegos this activity began in 1979, by a group of professionals led by Dr. Francisco Riverón Mena, who stayed for more than ten years in charge of cardiac stimulation, at the Dr. Gustavo Aldereguía Lima Hospital. The present work aims to describe the method for permanent pacemaker implantation applied in said institution, introduced by Dr. Riverón, as an alternative to the conventional mode. This technique requires very little use of ionizing radiation; It is effective and safer, both for the patient and for the health personnel, since fluoroscopy is used only at the last moment of the procedure, which differentiates it from the conventional method. Although it is not currently practiced, during the stage that it was applied in the hospital, it provided security to patients and health personnel, so its use should be resumed.

Abstract With the aim to reach the maximum recovery of bulk and specialty bioproducts while minimizing waste generation, a multi-product biorefinery for ethanol and lactic acid production from the biomass of cyanobacterium Arthrospira platensis was investigated. Therefore, the residual biomass resulting from different pretreatments consisting of supercritical fluid extraction (SF) and microwave assisted extraction with non-polar (MN) and polar solvents (MP), previously applied on A. platensis to extract bioactive metabolites, was further valorized. In particular, it was used as a substrate for fermentation with Saccharomyces cerevisiae LPB-287 and Lactobacillus acidophilus ATCC 43121 to produce bioethanol (BE) and lactic acid (LA), respectively. The maximum concentrations achieved were 3.02 ± 0.07 g/L of BE by the MN process at 120 rpm 30 °C, and 9.67 ± 0.05 g/L of LA by the SF process at 120 rpm 37 °C. An economic analysis of BE and LA production was carried out to elucidate the impact of fermentation scale, fermenter costs, production titer, fermentation time and cyanobacterial biomass production cost. The results indicated that the critical variables are fermenter scale, equipment cost, and product titer; time process was analyzed but was not critical. As scale increased, costs tended to stabilize, but also more product was generated, which causes production costs per unit of product to sharply decrease. The median value of production cost was US$ 1.27 and US$ 0.39, for BE and LA, respectively, supporting the concept of cyanobacterium biomass being used for fermentation and subsequent extraction to obtain ethanol and lactic acid as end products from A. platensis.

Background. Worldwide, gastrointestinal nematodes (GIN) cause losses in livestock production, because in some animals they can cause weight loss or death. Combating these GIN has been based on the use of anthelmintics. However, the misuse of these treatments has caused anthelmintic resistance. Therefore, there is currently a search for new biological alternatives for the control of gastrointestinal nematodes. One of these alternatives is the use of fungal extracts for nematode control. Objectives. To utilize the in vitro larval exsheathment inhibition test to evaluate organic extracts of edible fungi Pleurotus eryngii, P. djamor and Lentinula edodes, against Haemonchus contortus (L3). Methodology. Extracts were prepared from the basidiomes of the fungal species mentioned. In the case of P. eryngii and P. djamor, they were placed in a hydroalcoholic mixture (methanol/water 70:30). On the other hand, L. edodes basidiomes were macerated with distilled water for 24 hours. The extracts were filtered with a cotton/gauze system and through Whatman paper (#4) and were concentrated using a rotary evaporator until the liquid residue was removed and kept at -4 °C until use. To determine the percentage of larval exsheathment inhibition, larvae were exposed to different concentrations (156.25, 312.5, 625, 1250, and 2500 µg/mL) with their respective negative controls (PBS) for 60 minutes. The effective concentration 50% (EC50) was calculated by means of probit analysis. Results. The extracts with the best activity were P. djamor and L. edodes with an effective concentration (EC50) of 533.3 and 558.5 µg/mL, respectively. Implications. This in vitro evaluation provides results that suggest the need for further in vitro studies with more fungi species and other types of extraction procedures. Conclusion. The present study demonstrated that the use of extracts of P. eryngii, P. djamor and L. edodes was shown to have in vitro anthelmintic activity against the larval exsheathment of H. contortus.

Abstract Given its biocompatibility, rheological, and physiological properties, hyaluronic acid (HA) has become a biomaterial of increasing interest with multiple applications in medicine and cosmetics. In recent decades, microbial fermentations have become an important source for the industrial production of HA. However, due to its final applications, microbial HA must undergo critical and long purification processes to ensure clinical and cosmetic grade purity. Aqueous two-phase systems (ATPS) have proven to be an efficient technique for the primary recovery of high-value biomolecules. Nevertheless, their implementation in HA downstream processing has been practically unexplored. In this work, polyethylene glycol (PEG)–citrate ATPS were used for the first time for the primary recovery of HA produced with an engineered strain of Streptococcus equi subsp. zooepidemicus. The effects of PEG molecular weight (MW), tie-line length (TLL), volume ratio (VR), and sample load on HA recovery and purity were studied with a clarified fermentation broth as feed material. HA was recovered in the salt-rich bottom phase, and its recovery increased when a PEG MW of 8000 g mol−1 was used. Lower VR values (0.38) favoured HA recovery, whereas purity was enhanced by a high VR (3.50). Meanwhile, sample load had a negative impact on both recovery and purity. The ATPS with the best performance was PEG 8000 g mol−1, TLL 43% (w/w), and VR 3.50, showing 79.4% HA recovery and 74.5% purity. This study demonstrated for the first time the potential of PEG–citrate ATPS as an effective primary recovery strategy for the downstream process of microbial HA.

The interest in using essential oils for biotechnological and biomedical applications has been increasing because of their unique properties, such as their roles as preservatives, antioxidants, antimicrobial agents, and therapeutic agents, with oregano oil being a notable example. However, the bioactivity and stability of oregano oil can be compromised because of its volatile nature and external factors like exposure to light, heat, or oxygen. To protect oregano oil from these adverse effects and enhance its potential, microencapsulation has been employed. Nevertheless, studies evaluating the economic feasibility of this process are still limited. In this context, this study combines an environmental impact assessment by applying the life cycle assessment (LCA) methodology and an economic evaluation of three different scenarios (A, B, and C) for the production of oregano oil microparticles by a spray dryer. In Scenario A, only modified starch was used to prepare the emulsion; in Scenario B, the modified starch was replaced with gum arabic; and in Scenario C, the gum arabic, maltodextrin, and modified starch were combined. The results indicated that Scenario B presents the best environmental performance for all impact categories analyzed (global warming, fossil resource scarcity, mineral resource scarcity, terrestrial acidification, freshwater eutrophication, and marine eutrophication). However, the composting of bio-waste end-of-life presents better environmental performance for the other scenarios (A and C). In Scenario B, the process with the lowest production cost per gram of microcapsules is the most promising for meeting the demands of the aspects analyzed. [ABSTRACT FROM AUTHOR]

Carbon neutrality to limit global warming is an increasing challenge for all industries, particularly for the cement industry, due to the chemical emission of the process. For decades, reducing the clinker factor has been one of the main strategies to reduce the carbon footprint. Additional cuttings in the clinker content of cements seem possible with the upsurge of novel supplementary cementitious materials. This potential contribution represents only a fraction of the required carbon reductions for achieving the goal of carbon neutrality in the coming decades. This paper describes the current situation of the cement industry in Latin America and the Caribbean and the global opportunities and strategies to reduce the carbon footprint of cement and concrete and their adaptation to the regional conditions. Besides describing emerging supplementary cementitious materials, the potential contributions of industrialization and quality control are discussed. Moreover, limitations related to geography and standardization are analyzed. Regional considerations are made given the specific prospects of human development.

The current production of a number of commodity chemicals relies on the exploitation of fossil fuels and hence has an irreversible impact on the environment. Biotechnological processes offer an attractive alternative by enabling the manufacturing of chemicals by genetically modified microorganisms. However, this alternative approach poses some important technical challenges that must be tackled to make it competitive. On the one hand, the design of biotechnological processes is based on trial-and-error approaches, which are not only costly in terms of time and money, but also result in suboptimal designs. On the other hand, the manufacturing of chemicals by biological processes is almost exclusively carried out by batch or fed-batch cultures. Given that batch cultures are expensive and not easy to scale, technical means must be developed to make continuous cultures feasible and efficient. In order to address these challenges, we have developed a mathematical model able to integrate in a single model both the genome-scale metabolic model for the organism synthesizing the chemical of interest and the dynamics of the bioreactor in which the organism is cultured. Such a model is based on the use of Flexible Nets, a modeling formalism for dynamical systems. The integration of a microscopic (organism) and a macroscopic (bioreactor) model in a single net provides an overall view of the whole system and opens the door to global optimizations. As a case study, the production of citramalate with respect to the substrate consumed by E. coli is modeled, simulated and optimized in order to find the maximum productivity in a steady-state continuous culture. The predicted computational results were consistent with the wet lab experiments.

Exosomes are cell-derived vesicles that present attractive characteristics such as nano size and unique structure for their use as drug delivery systems for drug therapy, biomarkers for prognostic, diagnostic and personalized treatments. So far, one of the major challenges for therapeutic applications of exosomes is the development of optimized isolation methods. In this context, aqueous two-phase systems (ATPS) have been used as an alternative method to isolate biological molecules and particles with promising expectations for exosomes. In this work, fractionation of exosomes obtained from CaCo2 cell line and culture media contaminants were individually performed in 20 polymer-polymer ATPS. The effect of design parameters such as polymer composition, molecular weight, and tie-line length (TLL) on polyethylene glycol (PEG)-Dextran, Dextran-Ficoll and PEG-Ficoll systems was studied. After partition analysis, 4 of the 20 systems presented the best exosome fractionation from contaminants under initial conditions, which were optimized via salt addition (NaCl) to a final concentration of 25 mM, to improve collection efficiency. The PEG 10,000 gmol-1 -Dextran 10,000 gmol-1 system at TLL 25% w/w with NaCl, showed the best potential isolation efficiency. Following this proposed strategy, an exosome purification factor of 2 in the top PEG-rich phase can be expected furtherly demonstrating that ATPS have the potential for the selective recovery of these promising nanovesicles.

Background. Small ruminants that graze in the low deciduous forest (LDF) face problems related to malnutrition and gastrointestinal nematode infections (GIN). Over the past 30 years, FMVZ-UADY researchers have conducted extensive research to understand the interaction between small ruminant nutrition, plants consumed in LDF, and GINs. Objective. Review the work carried out in the FMVZ-UADY to explain why these problems of malnutrition and GIN infection occur and how to solve them. Main findings. Research shows that the complex interaction between small ruminants, LDF plants, and GINs helps explain malnutrition problems and GIN infections. Both of these problems have also been shown to abate through dietary supplementation, which must be designed to deliver the limiting nutrients in the LDF. Producers can use criteria such as weight gain and body condition score (BCS) to monitor that their animals are nutritionally adequate. To maintain strong resilience and resistance against GINs, growing animals should achieve> 100 g / day weight gain and adults should maintain> 2.5 BCS. It has also been confirmed that many LDF plant species contain secondary compounds (SC) that can affect the biology of different life stages of GIN, so they could be used as nutraceuticals. However, some SC can also adversely affect the digestion and absorption of nutrients in sheep and goats, so they must be used with care. The presence of plants containing SC with anthelmintic activity has made it possible to explore the capacity of animals to self-medicate. In these studies, it has been shown that goats do not express a “curative” self-medication behavior against GINs but do exhibit “preventive” self-medication behaviors that could allow them to limit their GIN burdens. However, animals seem to favor a preventive behavior aimed at avoiding nitrogen:energy imbalances in the consumed diet. Implications: Many LDF plant species have a high potential to be used for both nutritional and medicinal purposes in small ruminants, therefore, these species could be considered as a nutraceutical resource. Conclusions. The work carried out in the last 3 decades has shown us that the optimal use of LDF by sheep and goats will be achieved through a better understanding of the interaction between animals, their GIN and the plants of the LDF.

Hyaluronic acid (HA) is a biopolymer with a wide range of applications, mainly in the cosmetic and pharmaceutical sectors. Typical industrial-scale production utilizes organisms that generate HA during their developmental cycle, such as Streptococcus equi sub. zooepidemicus. However, a significant disadvantage of using Streptococcus equi sub. zooepidemicus is that it is a zoonotic pathogen, which use at industrial scale can create several risks. This creates opportunities for heterologous, or recombinant, production of HA. At an industrial scale, the recovery and purification of HA follow a series of precipitation and filtration steps. Current recombinant approaches are developing promising alternatives, although their industrial implementation has yet to be adequately assessed. The present study aims to create a theoretical framework to forecast the advantages and disadvantages of endogenous and recombinant strains in production with the same downstream strategy. The analyses included a selection of the best cost-related recombinant and endogenous production strategies, followed by a sensitivity analysis of different production variables in order to identify the three most critical parameters. Then, all variables were analyzed by varying them simultaneously and employing multiple linear regression. Results indicate that, regardless of HA source, production titer, recovery yield and bioreactor scale are the parameters that affect production costs the most. Current results indicate that recombinant production needs to improve current titer at least 2-fold in order to compete with costs of endogenous production. This study serves as a platform to inform decision-making for future developments and improvements in the recombinant production of HA.

En esta investigación se compara el efecto del modelo de consumo neoliberal en adolescentes, hombres y mujeres, de Quito (Ecuador) y Santiago (Chile). El objetivo es describir estilos de consumo, actitud hacia el dinero y materialismo en adolescentes de ambas ciudades y comparar de acuerdo a país de procedencia y género de los participantes. La muestra abarca 799 adolescentes de entre 14 y 17 años de edad, de Ecuador y Chile, la cual se obtuvo a través de un muestreo por conglomerado bietápico. Los resultados indican diferencias por género y ciudad respecto a la impulsividad en la compra, con los hombres de Quito como quienes tienen una actitud más impulsiva. Y en relación con la actitud hacia la compra se hallaron diferencias significativas por género, observando que los hombres son quienes le dan mayor estatus de poder y felicidad personal.