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CCB. Artículos indexados en Scopus

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Some stability and strong convergence results for the algorithm with perturbations for a T-Ciric quasicontraction in CAT(0) spaces

Calderón Sanchez, Kenyi | 2023

In this paper, we establish the stability and strong convergence theorems, for the three-step iteration with perturbations for a T-Ciric quasicontraction, in the environment of the CAT(0) space. Finally, an application to the integral-type contraction and an example are shown

Diagnóstico y manejo actual de la acalasia

Forero-Vásquez, Bryan Nicolás | 2023

Introducción. La acalasia es un trastorno motor del esófago poco común, de etiología no clara, caracterizado por la pérdida de relajación del esfínter esofágico inferior, pérdida del peristaltismo normal, regurgitación y disfagia. Métodos. Se realizó una revisión narrativa de la literatura en revistas científicas y bases de datos en español e inglés, con el fin de presentar información actualizada en lo referente al diagnóstico y tratamiento de esta patología. Resultado. Se presenta la actualización de los criterios de los trastornos motores esofágicos según la clasificación de Chicago (CCv4.0) para el diagnóstico de acalasia y sus subtipos de acuerdo con los nuevos criterios, así como los tratamientos actuales. Conclusión. La acalasia es un trastorno esofágico multimodal, con manifestaciones de predominio gastrointestinal, por lo que su diagnóstico y abordaje terapéutico oportuno es esencial para mejorar la calidad de vida de los pacientes.

Estimates, trends, and drivers of the global burden of type 2 diabetes attributable to PM2·5 air pollution, 1990–2019: an analysis of data from the Global Burden of Disease Study 2019

Burkart, Katrin | 2022

Background Experimental and epidemiological studies indicate an association between exposure to particulate matter (PM) air pollution and increased risk of type 2 diabetes. In view of the high and increasing prevalence of diabetes, we aimed to quantify the burden of type 2 diabetes attributable to PM2·5 originating from ambient and household air pollution. Methods We systematically compiled all relevant cohort and case-control studies assessing the effect of exposure to household and ambient fine particulate matter (PM2·5) air pollution on type 2 diabetes incidence and mortality. We derived an exposure–response curve from the extracted relative risk estimates using the MR-BRT (meta-regression— Bayesian, regularised, trimmed) tool. The estimated curve was linked to ambient and household PM2·5 exposures from the Global Burden of Diseases, Injuries, and Risk Factors Study 2019, and estimates of the attributable burden (population attributable fractions and rates per 100000 population of deaths and disability-adjusted life-years) for 204 countries from 1990 to 2019 were calculated. We also assessed the role of changes in exposure, population size, age, and type 2 diabetes incidence in the observed trend in PM2·5-attributable type 2 diabetes burden. All estimates are presented with 95% uncertainty intervals. Findings In 2019, approximately a fifth of the global burden of type 2 diabetes was attributable to PM2·5 exposure, with an estimated 3·78 (95% uncertainty interval 2·68–4·83) deaths per 100 000 population and 167 (117–223) disabilityadjusted life-years (DALYs) per 100000 population. Approximately 13·4% (9·49–17·5) of deaths and 13·6% (9·73–17·9) of DALYs due to type 2 diabetes were contributed by ambient PM2·5, and 6·50% (4·22–9·53) of deaths and 5·92% (3·81–8·64) of DALYs by household air pollution. High burdens, in terms of numbers as well as rates, were estimated in Asia, sub-Saharan Africa, and South America. Since 1990, the attributable burden has increased by 50%, driven largely by population growth and ageing. Globally, the impact of reductions in household air pollution was largely offset by increased ambient PM2·5. Interpretation Air pollution is a major risk factor for diabetes. We estimated that about a fifth of the global burden of type 2 diabetes is attributable PM2·5 pollution. Air pollution mitigation therefore might have an essential role in reducing the global disease burden resulting from type 2 diabetes

Musculoskeletal symptomatology in postharvest workers of a flower farm in Cundinamarca

Orozco Vásquez, Margarita María | 2022

Objetivos: Los síntomas musculoesquelético son una de las principales causas de perdida de la capacidad laboral y ausentismo en el mundo del trabajo. Los trabajadores de cultivo de flores están predispuestos a sufrirlas debido a la naturaleza de su trabajo. El Objetivo fue identificar la sintomatología musculoesquelética en los diferentes segmentos corporales. Material y Métodos: Estudio descriptivo con enfoque cuantitativo, la población fueron 135 trabajadores del área de postcosecha de un cultivo de flores ubicado en un municipio aledaño a la ciudad de Bogotá; se aplicaron 2 instrumentos, una encuesta de caracterización sociodemográfica y el cuestionario Nórdico Estandarizado. Resultados: Los segmentos corporales con presencia de síntomas fueron, la muñeca derecha 34%, espalda alta 32%, baja 27%, pies y tobillos 26%. El 99% de los rabajadores, atribuye su sintomatología músculo esquelética a la actividad laboral

The economic well-being of nations is associated with positive daily situational experiences

Gardiner, Gwendolyn | 2023

People in economically advantaged nations tend to evaluate their life as more positive overall and report greater well-being than people in less advantaged nations. But how does positivity manifest in the daily life experiences of individuals around the world? The present study asked 15,244 college students from 62 nations, in 42 languages, to describe a situation they experienced the previous day using the Riverside Situational Q-sort (RSQ). Using expert ratings, the overall positivity of each situation was calculated for both nations and individuals. The positivity of the average situation in each nation was strongly related to the economic development of the nation as measured by the Human Development Index (HDI). For individuals’ daily experiences, the economic status of their nation also predicted the positivity of their experience, even more than their family socioeconomic status. Further analyses revealed the specific characteristics of the average situations for higher HDI nations that make their experiences more positive. Higher HDI was associated with situational experiences involving humor, socializing with others, and the potential to express emotions and fantasies. Lower HDI was associated with an increase in the presence of threats, blame, and hostility, as well as situational experiences consisting of family, religion, and money. Despite the increase in a few negative situational characteristics in lower HDI countries, the overall average experience still ranged from neutral to slightly positive, rather than negative, suggesting that greater HDI may not necessarily increase positive experiences but rather decrease negative experiences. The results illustrate how national economic status influences the lives of individuals even within a single instance of daily life, with large and powerful consequences when accumulated across individuals within each nation.

Adjuvants approved for human use: What do we know and what do we need to know for designing good adjuvants?

Reyes, César | 2023

Adjuvants represent one of the most significant biotechnological solutions regarding vaccine development, thereby broadening the amount of candidates which can now be used and tested in vaccine formulations targeting various pathogens, as antigens which were previously discarded due to their low or null immunogenicity can now be included. Adjuvant development research has grown side-by-side with an increasing body of knowledge regarding immune systems and their recognition of foreign microorganisms. Alum-derived adjuvants were used in human vaccines for many years, even though complete understanding of their vaccination-related mechanism of action was lacking. The amount of adjuvants approved for human use has increased recently in line with attempts to interact with and stimulate the immune system. This review is aimed at summarising what is known about adjuvants, focusing on those approved for use in humans, their mechanism of action and why they are so necessary for vaccine candidate formulations; it also discusses what the future may hold in this growing research field

Unusual presentation of melanoma during the puerperium

Lamus, Sergio | 2023

El objetivo del artículo es describir las manifestaciones clínicas y el enfoque diagnóstico realizado en una paciente que presentó un melanoma durante el puerperio.

Current and Future Climate Extremes Over Latin America and Caribbean: Assessing Earth System Models from High Resolution Model Intercomparison Project (HighResMIP)

Avila Diaz, Alvaro Javier | 2023

Extreme temperature and precipitation events are the primary triggers of hazards, such as heat waves, droughts, floods, and landslides, with localized impacts. In this sense, the finer grids of Earth System models (ESMs) could play an essential role in better estimating extreme climate events. The performance of High Resolution Model Intercomparison Project (HighResMIP) models is evaluated using the Expert Team on Climate Change Detection and Indices (ETCCDI) over the 1981–2014 period and future changes (2021–2050) under Shared Socioeconomic Pathway SSP5–8.5, over ten regions in Latin America and the Caribbean. The impact of increasing the horizontal resolution in estimating extreme climate variability on a regional scale is first compared against reference gridded datasets, including reanalysis, satellite, and merging products. We used three different groups based on the resolution of the model’s grid (sg): (i) low (0.8° ≤ sg ≤ 1.87°), (ii) intermediate (0.5° ≤ sg ≤ 0.7°), and (iii) high (0.23° ≥ sg ≤ 0.35°). Our analysis indicates that there was no clear evidence to support the posit that increasing horizontal resolution improves model performance. The ECMWF-IFS family of models appears to be a plausible choice to represent climate extremes, followed by the ensemble mean of HighResMIP in their intermediate resolution. For future climate, the projections indicate a consensus of temperature and precipitation climate extremes increase across most of the ten regions. Despite the uncertainties presented in this study, climate models have been and will continue to be an important tool for assessing risk in the face of extreme events

A New Flavanone from Chromolaena tacotana (Klatt) R. M. King and H. Rob, Promotes Apoptosis in Human Breast Cancer Cells by Downregulating Antiapoptotic Proteins

Mendez, Gina | 2023

Chromolaena tacotana is a source of flavonoids with antiproliferative properties in human breast cancer cells, the most common neoplasm diagnosed in patients worldwide. Until now, the mechanisms of cell death related to the antiproliferative activity of its flavonoids have not been elucidated. In this study, a novel flavanone (3′,4′-dihydroxy-5,7-dimethoxy-flavanone) was isolated from the plant leaves and identified by nuclear magnetic resonance (NMR) and mass spectrometry (MS). This molecule selectively inhibited cell proliferation of triple-negative human breast cancer cell lines MDA-MB-231 and MCF-7 whit IC50 values of 25.3 μg/mL and 20.8 μg/mL, respectively, determined by MTT assays with a selectivity index greater than 3. Early and late pro-apoptotic characteristics were observed by annexin-V/7-AAD detection, accompanied by a high percentage of the Bcl-2 anti-apoptotic protein inactivated and the activation of effector Caspase-3 and/or 7 in breast cancer cells. It was verified the decreasing of XIAP more than Bcl-2 anti-apoptotic proteins expression, as well as the XIAP/Caspase-7 and Bcl-2/Bax complexes dissociation after flavanone treatment. Docking and molecular modeling analysis between the flavanone and the antiapoptotic protein XIAP suggests that the natural compound inhibits XIAP by binding to the BIR3 domain of XIAP. In this case, we demonstrate that the new flavanone isolated from leaves of Chomolaena tacotana has a promising and selective anti-breast cancer potential that includes the induction of intrinsic apoptosis by downregulation of the anti-apoptotic proteins XIAP and Bcl-2. New studies should deepen these findings to demonstrate its potential as an anticancer agent.

In vitro production of buffalo embryos in Colombia – results of the addition of growth factors and antioxidants to defined culture medium

Chavez Rodriguez, Aldemar | 2023

To increase the success rate of the in vitro production (IVP) system of embryos in buffalo, it is necessary to improve parameters. This field requires more research since its results are low compared to cattle. In this study carried out in Colombia, a modification of the methodology to produce buffalo IVP embryos is described, and 24 non-lactating females, aged 4 to 11 years old were included. Follicular wave was synchronised by ablation of the follicles within the ovary, seven days later all follicles were aspirated to obtain oocytes for maturation, fertilisation and embryo production. For all culture media used, animal protein was avoided. Culture media were supplemented with growth factors and other molecules associated with embryonic development. Special care was taken in adding supplements to protect the zygotes against the harmful effect of oxygen free radicals in the culture medium. Two aspiration series were performed 15 days apart. The average number of oocytes obtained by aspiration was 11.33, the number of blastocysts was 3.05, and the obtained blastocyst production rate (36.2%) was higher than literature reports for this species; we hypothesise that this increase is associated with the supplements added. It was possible to observe a female that produced 50 oocytes. Subsequent research is needed to evaluate the effect of the medium on embryo quality and pregnancy rates. A cost analysis of the new proposed medium is required, since all supplements must be imported and handled with a cold chain of up to -80oC, making it more expensive and restricting widespread use. Finally, it is shown that with three embryos per aspiration, at least one pregnancy can be successful after the aspiration, which is one of the objectives of the IVP system

Acute appendicitis during the COVID-19 pandemic: Experience in a high-level complex center in Boyacá, Colombia

Támara-López, José Antonio | 2023

Introduction. The COVID-19 pandemic varied the way health systems were attended, thus affecting pathologies not related to respiratory infections, such as acute appendicitis. Fear of SARS-CoV-2 infection and mobility restrictive measures may have implied a longer time from the onset of symptoms to consultation of the emergency department, leading to intraoperative and postoperative complications. Methods. Retrospective cross-sectional descriptive observational study, identifying all patients diagnosed with acute appendicitis and taken for appendectomy, divided into two groups, considered pre-pandemic, from September 1, 2018 to March 15, 2020, and pandemic, from March 16, 2020 to September 30, 2021. Results. One-thousand patients were identified, 501 patients were distributed in the pre-pandemic group and 499 in the pandemic group. The average consultation time from the time of onset of symptoms to consultation was 43 hours in the pre-pandemic group and almost 45 hours in the pandemic. Discussion. Despite the restrictions due to the disease caused by the new coronavirus and the fear that may existed due to contagion, in our center there was no evidence of a change in the management and presentation of patients diagnosed with acute appendicitis.

Characterization of variables associated with sports performance: interdisciplinarity in women's soccer in Colombia

Becerra Patiño, Boryi Alexander | 2023

Characterizing the variables associated with sports performance in women's soccer is necessary to favor the sports preparation of the player. This study aimed to evaluate the association between performance characteristics (morphofunctional) and characteristics (psychosocial and nutritional) in female soccer players in Bogota. The study included 81 players grouped by position, based on the analysis of morphological (somatotype), functional (endurance, speed, and strength), psychosocial (socioeconomic status, economic situation, educational level, subsidized health regime, family members), and nutritional (dietary habits, food, quantity and type of food and intolerances) variables. A total of 241 variables were analyzed, grouped into 21 groups of variables, of which eight groups were analyzed in depth and showed statistically significant differences. The study had a quantitative approach, correlational study type, and non-experimental crosssectional design with Bernoulli sampling. The statistical treatment was performed using the statistical program ® version 4.1.0 based on the principal component analysis method, multiple factor analysis, and RV coefficient. It can be evidenced that the profile induced by the position variable correlates with the profile induced by the group of RSA variables. The profile induced by the lower body strength variables correlates with the profile induced by the social variables. The lower body strength variables and the social and family characteristics reveal that players living above 2550 meters of altitude are characterized by having high values in variables such as net strength at 100, 150, and 200 m/s, left-right leg, and vertical peak strength. These are in the subsidized regime and are characterized by living in small families. In contrast, players living at an altitude of 2600 meters were characterized by reaching high levels in variables such as peak power (W/kg), jump height (cm), reactive force index (m/s), eccentric deceleration (N/s/kg), maximum peak velocity (m/s), average concentric force and average eccentric force, characterized by living in more prominent families. Thus, it can be determined that the context of female athletes significantly influences the muscle strength manifestation profile. Finally, the importance of interdisciplinarity in women's soccer is highlighted, seeking to understand that sports performance depends on the interaction of variables. Thus, interdisciplinary research opens a scenario of possibilities where the different variables that influence the sports performance of female soccer players and athletes can be understood under the interactions that occur in the competitive act. © 2023, Editura Universitatii din Pitesti. All rights reserved.

Improving sustainability teaching by grouping and interrelating pedagogical approaches and sustainability competences: Evidence from 15 Worldwide Higher Education Institutions

Lozano, Rodrigo | 2023

Education Institutions (HEIs). This paper's aim is to provide deeper insights into the system of pedagogical approaches and sustainability competences, as well as how these interrelate. A survey was developed to investigate sustainability teaching in 15 HEIs. The survey was sent to educators of each HEI from which 668 responses were obtained. The responses were analysed in a five-step process: (1) descriptive statistics; (2) Pearson correlations; (3) principal component analyses (PCAs) to detect groups; (4) Pearson correlations between the groups; and (5) regressions. The first step provided the base to carry out the PCAs, from which three groups for the pedagogical approaches (Universal, Social, and Environmental) and three for the sustainability competences (Extrospective-social, Introspective-personal, and Cogitative-processual) were obtained. The correlations between the groups showed that: (1) the competences are closely interrelated; (2) the pedagogical approaches are somehow interrelated; and (3) the pedagogical approaches are somehow interrelated to the competences. The regressions showed that the Universal and Social groups would be most suitable to develop all the competences' groups. The Environmental group develops only the cogitative-processual competences' group. The results served as bases to propose the Sustainability Teaching System (STS), which provides deeper insights into the system of pedagogical approaches and sustainability competences by grouping them, as well as showing directionality and strength. To improve sustainability teaching, it is necessary to understand the pedagogical approaches' groups and how they can develop the competences' groups.

Burden of infectious disease studies in Europe and the United Kingdom: a review of methodological design choices

Charalampous, Periklis | 2023

This systematic literature review aimed to provide an overview of the characteristics and methods used in studies applying the Disability-Adjusted Life Years (DALY) concept for infectious diseases within European Union (EU)/European Economic Area (EEA)/European Free Trade Association (EFTA) countries and the United Kingdom. Electronic databases and grey literature were searched for articles reporting the assessment of DALY and its components. We considered studies in which researchers performed DALY calculations using primary epidemiological data input sources. We screened 3,053 studies of which 2,948 were excluded and 105 studies met our inclusion criteria. Of these studies, 22 were multi-country and 83 were single-country studies, of which 46 were from the Netherlands. Food- and water-borne diseases were the most frequently studied infectious diseases. Between 2015 and 2022, the number of burden of infectious disease studies was 1.6 times higher compared to that published between 2000 and 2014. Almost all studies (97%) estimated DALYs based on the incidence- and pathogen-based approach and without social weighting functions; however, there was less methodological consensus with regards to the disability weights and life tables that were applied. The number of burden of infectious disease studies undertaken across Europe has increased over time. Development and use of guidelines will promote performing burden of infectious disease studies and facilitate comparability of the results.

Cryostorage of white cachama (Piaractus orinoquensis) sperm: Effects on cellular, biochemical and ultrastructural parameters

Medina Robles, Victor Mauricio | 2023

To date, little attention has been paid to identifying the effects of long-term cryopreservation on sperm quality for Piaractus orinoquensis. The object of this study was therefore to evaluate the effect of long-term cryopreservation (24 h, 1, 6 and 12 months) on sperm motility, viability, DNA integrity, ATP content, total antioxidant capacity (TAC), morphology and sperm ultrastructure in this species. Milt samples from six males were cryopreserved in a medium containing final concentrations of 7.5% Me2SO, 4.1% glucose and 9.0% egg yolk. The samples were frozen in liquid nitrogen (LN) vapor and stored in LN for periods of 24 h and 1, 6 and 12 months. After thawing, both the motility rate and the viability decreased significantly compared with fresh sperm; however, these parameters did not differ among the four cryopreservation times. The DNA integrity and ATP content decreased significantly after 6 months of cryopreservation. There were no significant differences in TAC values between fresh and cryopreserved sperm. The total sperm abnormalities in cryopreserved samples were about 5-fold higher than in fresh sperm; short tail was the most common defect occurring after cryostorage. The ultrastructural analysis reveals that P. orinoquensis spermatozoa consist of an ovoid head without acrosome, a cylindrical mid-piece, and a single flagellum. The nuclear fossa is located at the base of the nucleus and contains the centriolar complex. There are 1–2 ring-shaped mitochondria located in the mid-piece. The flagellum shows a 9 + 2 organization of microtubules in the axoneme. Post-thaw spermatozoa presented damage such as swelling and rupture of the plasma membrane, mitochondrial damage, loss of the electron-dense chromatin of the nucleus, and degeneration in the middle region

Assessment microbial risks for the presence of Cryptosporidium spp. and Giardia spp. based on the surveillance of the water supply systems in Colombia, 2014–2018

Guzman Barragan, Blanca Lisseth | 2022

Cryptosporidium spp. and Giardia spp. cause gastrointestinal diseases of zoonotic origin as well transmitted from person to person, being various reported outbreaks associated with water. The infecting (oo)cyst forms of these parasites are highly resistant to water treatments such as chlorine disinfection and fast filtration. The objective of this study was to assess the microbial risk of infection and symptomatic illness by the ingestion of Giardia spp. and Cryptosporidium spp. in water for human consumption in Colombia, based on the results of water quality surveillance. The detection method was according to the USEPA method 1623. Concentration data of the different points of distribution were grouped according to the pathogen and type of treatment (no treatment; chlorine treatment; chlorine treatment + coagulant). Annual microbial risks of infection and symptomatic diseases were estimated using the quantitative microbial risk assessment approach that included parasite concentrations, the dose–response model, the ingestion rates of water by children and adults, and the morbidity rate of the diseases. The mean annual microbial risk of infection for Giardia spp. was 29.8% for treated water and 50.4% for untreated water, while being 6.0% and 17.7%, respectively, for Cryptosporidium spp. Microbial risk of symptomatic illness for Giardia spp, was 8.2% for treated water and 13.9% for untreated water, while being 3.6% and 10.6%, respectively, for Cryptosporidium spp. The estimated annual microbial risks of infection exceeded the acceptable value of 10 4 (0.01%) recommended by USEPA. Results obtained in this study suggest the need to reduce the microbial risk of infection to protozoan parasites by improving the water treatment, by adopting better handling practices for livestock manure and treatment processes of human feces.

Stories, Generative Dialogues and Medical Education

Higuera Dagovett, Elkin | 2022

Introducción: La formación médica es un contexto con altos niveles de exigencia, que puede convertirse en fuente de estrés e influir en las relaciones interpersonales y el logro de metas. Objetivo: Comprender cómo se construyen en el diálogo dinámicas de afrontamiento ante las exigencias de un trabajo de investigación de estudiantes de medicina, que permitan desarrollar aprendizajes acerca del trabajo en equipo con eficiencia y productividad. Métodos: Estudio de caso con abordaje cualitativo. Resultados: Las dinámicas de relación se configuraron desde la imposibilidad para trabajar de manera colaborativa, y en relatos que explicaban la conducta de los otros como la causa de la falta de evolución y eficiencia del proyecto. Crear tramas conversacionales generativas que posibiliten emerger recursos, permite reconocer lo problemático como oportunidades para coevolucionar. Las subjetividades pueden ser reconocidas y reconfiguradas en el diálogo que crea nuevas opciones para el logro de metas comunes. Conclusiones: Las asesorías en grupos de estudiantes con desacuerdos que no posibilitan coevolucionar, pueden realizarse mediante diálogos generativos que permitan reflexiones y aprendizajes de posturas personales y dinámicas relacionales, para construir colaborativamente nuevas opciones, donde fortalezas, recursos internos y externos emerjan para el cumplimiento de metas.

Effects of Maternal Protein Supplementation at Mid-Gestation of Cows on Intake, Digestibility, and Feeding Behavior of the Offspring

Batista Nascimento, Karolina | 2022

: It is well known that intrauterine growth-restricted offspring present physiologic and metabolic modifications later in life. Therefore, understanding the impact of the maternal nutritional plane on feed intake patterns may lead to new feeding strategies to improve the feed efficiency and performance of beef cattle. In this study, we have evaluated the effect of maternal protein supplementation (PS) during mid-gestation and its interaction with the offspring’s sex on the voluntary feed intake and nutrient use of the progeny. Our results show that PS during midgestation increases performance and improves the voluntary feed intake of the offspring. Prenatal PS induced favorable changes in the feeding behavior, in which CON offspring spent more time per day eating supplements and ruminating but spent fewer periods in idleness. Maternal protein restriction demonstrated positive effects on the ability to digest the nutrients of male calves. In summary, our data show that PS alters the gain potential, indirectly demonstrating an increase in their nutritional requirements. In contrast, protein restriction causes a compensatory mechanism on the offspring’s nutrient useability in a sex-dependent manner, increasing the total tract digestibility of nutrients in response to a growth-restriction exposure during intrauterine development

In Vitro and In Silico Study of the α-Glucosidase and Lipase Inhibitory Activities of Chemical Constituents from Piper cumanense (Piperaceae) and Synthetic Analogs

Prieto, Juliet | 2022

Digestive enzymes are currently considered important therapeutic targets for the treatment of obesity and some associated metabolic diseases, such as type 2 diabetes. Piper cumanense is a species characterized by the presence of bioactive constituents, particularly prenylated benzoic acid derivatives. In this study, the inhibitory potential of chemical constituents from P. cumanense and some synthesized compounds was determined on digestive enzymes (pancreatic lipase (PL) and α-glucosidase (AG)). The methodology included isolating and identifying secondary metabolites from P. cumanense, synthesizing some analogs, and a molecular docking study. The chemical study allowed the isolation of four prenylated benzoic acid derivatives (1–4). Four analogs (5–8) were synthesized. Seven compounds were found to significantly inhibit the catalytic activity of PL with IC50 values between 28.32 and 55.8 µM. On the other hand, only two compounds (6 and 7) were active as inhibitors of AG with IC50 values lower than 155 µM, standing out as the potential multitarget of these chromane compounds. Enzyme kinetics and molecular docking studies showed that the bioactive compounds mainly interact with amino acids other than those of the catalytic site in both PL and AG. This work constitutes the first report on the antidiabetic and antiobesity potential of substances derived from P. cumanense.

Stereo electronic principles for selecting fully-protective, chemically-synthesised malaria vaccines

Patarroyo, Manuel-Elkin | 2022

Major histocompatibility class II molecule-peptide-T-cell receptor (MHCII-p-TCR) complex-mediated antigen presentation for a minimal subunit-based, multi-epitope, multistage, chemically-synthesised antimalarial vaccine is essential for inducing an appropriate immune response. Deep understanding of this MHCII-p-TCR complex’s stereo-electronic characteristics is fundamental for vaccine development. This review encapsulates the main principles for achieving such epitopes’ perfect fit into MHC-II human (HLADRβ̞1*) or Aotus (Aona DR) molecules. The enormous relevance of several amino acids’ physico-chemical characteristics is analysed in-depth, as is data regarding a 26.5 ± 2.5Å distance between the farthest atoms fitting into HLA-DRβ1* structures’ Pockets 1 to 9, the role of polyproline II-like (PPIIL) structures having their O and N backbone atoms orientated for establishing H-bonds with specific HLA-DRβ1*-peptide binding region (PBR) residues. The importance of residues having specific charge and orientation towards the TCR for inducing appropriate immune activation, amino acids’ role and that of structures interfering with PPIIL formation and other principles are demonstrated which have to be taken into account when designing immune, protection-inducing peptide structures (IMPIPS) against diseases scourging humankind, malaria being one of them