Influence of the Surface Topography of Titanium Dental Implants on the Behavior of Human Amniotic Stem Cells.

The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of grit blasting and subsequent acid etching (GBLAST + AE). Human amniotic mesenchymal (hAMSCs) and epithelial stem cells (hAECs) isolated from the amniotic membrane have attractive stem-cell properties. They were cultured on titanium surfaces to analyze their impact on biological behavior. The surface roughness, microhardness, wettability, and surface energy were analyzed using interferometric microscopy, Vickers indentation, and drop-sessile techniques. The GBLAST and GBLAST + AE surfaces showed higher roughness, reduced hydrophilicity, and lower surface energy with significant differences. Increased microhardness values for GBLAST and GBLAST + AE implants were attributed to surface compression. Cell viability was higher for hAMSCs, particularly on GBLAST and GBLAST + AE surfaces. Alkaline phosphatase activity enhanced in hAMSCs cultured on GBLAST and GBLAST + AE surfaces, while hAECs showed no mineralization signals. Osteogenic gene expression was upregulated in hAMSCs on GBLAST surfaces. Moreover, α2 and ß1 integrin expression enhanced in hAMSCs, suggesting a surface-integrin interaction. Consequently, hAMSCs would tend toward osteoblastic differentiation on grit-blasted surfaces conducive to osseointegration, a phenomenon not observed in hAECs.

Placental apoptosis increased by hypoxia inducible factor-1 stabilization is counteracted by leptin†.

During pregnancy, apoptosis is a physiological event critical in the remodeling and aging of the placenta. Increasing evidence has pointed toward the relevance of hypoxia as modulator of trophoblast cell death. Previous reports have shown that leptin, a placental cytokine, promotes cell survival in both cell culture and placental explant models. The aim of this work is to establish the role of leptin in apoptosis under hypoxic condition in trophoblast cells. In this study, we evaluated the effect of cobalt chloride, a hypoxia mimicking agent that stabilizes the expression of hypoxia-inducible factor-1 alpha, on Swan-71 and human placental explants. Hypoxia chamber was also used to generate 2% oxygen. Apoptosis was determined by the presence of apoptotic nucleus, fragmentation of DNA and Caspase-3 and PARP-1 cleavage. The pro-apoptotic proteins BAX, BID, BAD, and BAK and the anti-apoptotic effectors BCL-2, B-cell lymphoma-extra-large, and myeloid cell leukemia-1 were also analyzed. We found that hypoxia-inducible factor-1 alpha stabilization increased the appearance of apoptotic nucleus, fragmentation of DNA, and Caspase-3 and PARP-1 cleavage. Hypoxia mimicking conditions enhanced the expression of pro-apoptotic effectors BAX, BID, BAD, and BAK. Hypoxia-inducible factor-1 alpha stabilization also downregulated the level of BCL-2, B-cell lymphoma-extra-large, and myeloid cell leukemia-1. All these apoptotic parameters changes were reversed with leptin treatment. Moreover, we showed that leptin action on apoptosis modulation involves PI3K and MAPK signaling pathways. Obtained data demonstrate that hypoxia-inducible factor-1 alpha stabilization induces apoptosis in human placenta and leptin counteracts this effect, reinforcing its role as a survival cytokine.

New beam-based models for fire-induced buckling analysis of class 4 steel columns.

Steel cross-sections with thin walls are vulnerable to fire-induced buckling instability, which reduces their load-bearing capacity. Eurocode 3 design provisions have been found inadequate, leading to alternative methods such as effective design strategies and advanced structural models built mostly with shell FE, which can be complex. For Class 4 steel beam-columns subjected to fire conditions, beam-type modelling to predict the Flexural-Torsional Buckling (FTB) strength has been proposed as an alternative approach, but it has not yielded satisfactory results for large compressive load eccentricities. This paper presents two new low computational cost modelling strategies based on Timoshenko's beam FE to address this issue: the Single beam-column Model (SbcM) and the Cruciform beam-column Model (CbcM). The first consists of a single line of beam FE, while the second uses a grid of beam FE for more flexibility. Both strategies effectively simulate the FTB behaviour in Class 4 steel beam-column during a fire, offering quicker computations compared to shell models. Still, the single-line model is favoured for its simplicity, making it more efficient in analysing complex fire engineering problems.

Preparation and evaluation of (R)-(-)-carvone-doped polymeric resins as potential antibacterial dental materials.

OBJECTIVES: This study aimed to develop and evaluate resin-based antibacterial materials incorporating carvone for restorative dentistry. The objectives included assessing antimicrobial activity, conversion degree, mechanical properties, hydrolytic and hygroscopic behavior, cytotoxicity, among others. METHODOLOGY: Carvone was incorporated into resin-based materials following established protocols. Antimicrobial activity was evaluated against S. Aureus. Conversion degree, polimerization kinetics, mechanical properties, hydrolytic and hygroscopic behavior, cytotoxicity, and other properties were assessed using standardized tests and methodologies. RESULTS: Carvone-incorporated materials demonstrated significant antimicrobial activity, minimal changes in conversion degree, comparable mechanical properties, improved hydrolytic and hygroscopic behavior, and lack of cytotoxicity. Antimicrobial resins were obtained due to the hydrophobic nature of carvone and its ability to diffuse through the cell walls of microorganisms, causing membrane damage. The polymerization process yielded successful conversion, ensuring adequate material performance. SIGNIFICANCE: This study showcases that incorporating carvone into methacrylate-based resins can confer antimicrobial properties while preserving key material attributes. Antimicrobial activity against S. aureus is achieved without cytotoxicity in human fibroblasts. While flexural properties are affected only at carvone concentrations exceeding 9%, conversion degree and polymerization kinetics remain stable, except for a specific experimental formulation. These findings highlight the balanced integration of carvone. However, further work, including assessing antimicrobial performance against specific strains like S. Mutans and/or C. Albicans, and evaluating long-term effectiveness, is essential to establish the potential of these materials for dental restorations.

Consensus document for lipid profile testing and reporting in Spanish clinical laboratories: What parameters should a basic lipid profile include?

Cardiovascular diseases (CVD) continue to be the main cause of death in our country. Adequate control of lipid metabolism disorders is a key challenge in cardiovascular prevention that is far from being achieved in real clinical practice. There is a great heterogeneity in the reports of lipid metabolism from Spanish clinical laboratories, which may contribute to its poor control. For this reason, a working group of the main scientific societies involved in the care of patients at vascular risk, has prepared this document with a consensus proposal on the determination of the basic lipid profile in cardiovascular prevention, recommendations for its realization and unification of criteria to incorporate the lipid control goals appropriate to the vascular risk of the patients in the laboratory reports.

Consensus-based recommendations on physical activity and exercise in patients with diabetes at risk of foot ulcerations: a Delphi study.

BACKGROUND: Patients with diabetes mellitus are exposed to important complications. Currently little evidence exist on the guidelines that these patients, at some risk of foot ulceration, should follow for physical exercise. OBJECTIVES: To reach a consensus among multidisciplinary and international experts on physical activity/exercise recommendations for patients with diabetes, according to foot ulcer risk. METHODS: Using a three-round Delphi method, a panel composed of 28 multidisciplinary experts in the management of diabetic foot assessed 109 recommendations on physical activity/exercise for patients with diabetes mellitus, according to their risk of foot ulcer. Consensus was assumed when 80% of responses matched the same category (agreement/disagreement). RESULTS: Twenty-nine experts participated in the first and second rounds of consultation, and twenty-eight did so in the third, reaching final agreement on 86 of the 109 recommendations considered (78.9%). The study, thus, generated a consensus set of recommendations concerning different aspects of diabetic footcare before, during, and after exercise (e.g. when to examine the foot, how to assess it, what type of sock and insole to use, what types of exercise to perform, and when it is advisable to return to activity after an ulceration). CONCLUSION: This Delphi study generated recommendations based on the consensus of international experts on physical activity and exercise by patient with diabetes at risk of ulceration. Recommendations considered the state of the foot and the patient's history and status before physical activity and included information on intensity, duration, frequency, and progressions of physical activity/exercise, and the use of custom-made plantar orthoses, shoe prescription, and the convenience of returning to physical activity after an ulceration.

Consensus document for lipid profile determination and reporting in Spanish clinical laboratories. What parameters should be included in a basic lipid profile? / Documento de consenso para la determinación e informe del perfil lipídico en laboratorios clínicos españoles: ¿Qué parámetros debe incluir un perfil lipídico básico?

Cardiovascular diseases (CVD) continue to be the main cause of death in our country. Adequate control of lipid metabolism disorders is a key challenge in cardiovascular prevention that is far from being achieved in real clinical practice. There is a great heterogeneity in the reports of lipid metabolism from Spanish clinical laboratories, which may contribute to its poor control. For this reason, a working group of the main scientific societies involved in the care of patients at vascular risk, has prepared this document with a consensus proposal on the determination of the basic lipid profile in cardiovascular prevention, recommendations for its realization and unification of criteria to incorporate the lipid control goals appropriate to the vascular risk of the patients in the laboratory reports.

Human amniotic epithelial stem cells: Hepatic differentiation and regenerative properties in liver disease treatment.

The placenta and the extraembryonic tissues represent a valuable source of cells for regenerative medicine. In particular, the amniotic membrane possesses cells with stem cells characteristics that have attracted research attention. Human amniotic epithelial cells (hAECs) have unique and desirable features that position them over other stem cells, not only because of the unlimited potential supplied of, the easy access to placental tissues, and the minimal ethical and legal barriers associated, but also due to the embryonic stem cells markers expression and their ability to differentiate into the three germ layers. In addition, they are non-tumorigenic and have immunomodulatory and anti-inflammatory properties. Hepatic failure is one of the major causes of morbidity and mortality worldwide. Organ transplantation is the best way to treat acute and chronic liver failure, but there are several associated obstacles. Stem cells have been highlighted as alternative hepatocytes source because of their potential for hepatogenic differentiation. HAECs, in particular, have some properties that make them suitable for hepatocyte differentiation. In this work, we review the general characteristics of the epithelial stem cells isolated from human amniotic membrane as well as their ability to differentiate to hepatic cells. We also revise their regenerative properties, with the focus on their potential application in the liver disease treatment.

Validation and application of the Insulin Treatment Appraisal Scale in Cuban patients with type 2 diabetes mellitus.

INTRODUCTION: The purpose of this study was to validate the Insulin Treatment Appraisal Scale (ITAS) in the Cuban population with type 2 diabetes mellitus. MATERIAL AND METHODS: A cross-sectional, multicentre analytical study was performed in Cuba from February 2020 to April 2021; 199 patients were surveyed in a hospital institution and in primary healthcare. We used the Insulin Treatment Appraisal Scale, consisting of 20 items, with a minimum score of 20 points and a maximum of 100, where the higher the score, the worse the perception of insulin therapy. The validity of the instrument was determined by means of an exploratory factor analysis. The internal consistency and reliability of the scale were calculated by means of Cronbach's alpha coefficient. A K-means cluster analysis was performed to establish a cut-off point for poor perception of insulin therapy. RESULTS: The exploratory factor analysis supported the validity of the instrument, with a Cronbach's alpha of 0.747. There were statistically significant differences between patients under insulin and non-insulin treatment in terms of the answers given in all items of the scale. The total mean score obtained was 51.96 ±â€¯10.78, and it was lower in insulin users compared to those who used other drugs (49.79 ±â€¯10.07 vs 55.09 ±â€¯11.12). A score ≥65 was proposed as a cut-off point for poor perception of insulin therapy. A positive relationship was found between the body mass index values and the total score of the scale. Being female and current treatment not involving insulin were factors associated with low perception of insulin therapy. CONCLUSIONS: The instrument proved to be valid for the population in which it was applied. Insulin users turned out to be the ones with the best perception about its use. A cut-off point of ≥65 points for poor perception of insulin treatment was proposed for evaluation and comparison in future studies in other patient populations.

Development of Biodegradable Polyesters: Study of Variations in Their Morphological and Thermal Properties through Changes in Composition of Alkyl-Substituted (ε-DL) and Non-Substituted (ε-CL, EB, L-LA) Monomers.

Three series of polyesters based on monomer combinations of ε-caprolactone (ε-CL), ethylene brassylate (EB), and l-Lactide (LLA) with the alkyl substituted lactone ε-decalactone (ε-DL) were synthesized at different molar ratios. Copolymers were obtained via ring opening polymerization (ROP) employing TBD (1,5,7-triazabicyclo-[4.4.0]-dec-5-ene), an organic catalyst which can be handled under normal conditions, avoiding the use of glove box equipment. The molar monomer composition of resulting copolymers differed from theoretical values due to lower ε-DL reactivity; their Mn and Mw values were up to 14 kDa and 22.8 kDa, respectively, and distributions were (Ɖ) ≤ 2.57. The thermal stability of these materials suffered due to variations in their ε-DL molar content. Thermal transitions such as melting (Tm) and crystallization (Tc) showed a decreasing tendency as ε-DL molar content increased, while glass transition (Tg) exhibited minor changes. It is worth mentioning that changes in monomer composition in these polyesters have a strong impact on their thermal performance, as well as in their crystallization degree. Consequently, variations in their chemical structure may have an effect on hydrolyic degradation rates. It should be noted that, in future research, some of these copolymers will be exposed to hydrolytic degradation experiments, including characterizations of their mechanical properties, to determine their adequacy in potential use in the development of soft medical devices.

Synthesis of a Curing Agent Derived from Limonene and the Study of Its Performance to Polymerize a Biobased Epoxy Resin Using the Epoxy/Thiol-Ene Photopolymerization Technique.

This study describes the synthesis of a curing agent derived from limonene as well as its application to prepare biobased thermoset polymers via the epoxy/thiol-ene photopolymerization (ETE) method. A biobased commercial epoxy resin was used to synthesize a crosslinked polymeric matrix of polyether-polythioether type. The preparation of the curing agent required two steps. First, a diamine intermediate was prepared by means of a thiol-ene coupling reaction between limonene and cysteamine hydrochloride. Second, the primary amino groups of the intermediate compound were alkylated using allyl bromide. The obtained ditertiary amine-functionalized limonene compound was purified and characterized by FTIR and NMR spectroscopies along with GC-MS. The curing agent was formulated with a tetrafunctional thiol in stoichiometric ratio, and a photoinitiator at 1 mol % concentration, as the components of a thiol-ene system (TES). Two formulations were prepared in which molar concentrations of 30 and 40 mol % of the TES were added to the epoxy resin. The kinetics of the ETE photopolymerizations were determined by means of Real-Time FTIR spectroscopy, which demonstrated high reactivity by observing photopolymerization rates in the range of 1.50-2.25 s-1 for the epoxy, double bonds and thiol groups. The obtained polymers were analyzed by thermal and thermo-mechanical techniques finding glass transition temperatures (Tg) of 60 °C and 52 °C for the polymers derived from the formulations with 30 mol % and 40 mol % of TES, respectively. Potential applications for these materials can be foreseen in the area of coatings.

Controlled Release of Chlorogenic Acid from Polyvinyl Alcohol/Poly(γ-Glutamic Acid) Blended Electrospun Nanofiber Mats with Potential Applications in Diabetic Foot Treatment.

This work biosynthesized poly(γ-glutamic acid) (γ-PGA) produced by Bacillus licheniformis ATCC-9945a. This material was utilized to prepare electrospun nanofibers with solutions of 10% polyvinyl alcohol (PVA) (w/v) mixed with γ-PGA at 5 and 10% w/v, intended as a wound dressing for diabetic foot treatment. These solutions were loaded with chlorogenic acid (CGA), an active hypoglycemic agent. Morphological analysis showed a decrease in size of the fibers with the combination of PVA/γ-PGA compared to pure PVA nanofibers, which was attributed to the hydrogen bonding interactions between the glutaraldehyde vapors, γ-PGA, and PVA that permitted nanofiber cross-linking and allowed CGA release. The in vitro release analysis showed that the PVA membranes reached 28% delivery after the first 24 h. Notably, the nanofiber mat with PVA blended with 5% γ-PGA reached 57% delivery, and the PVA nanofiber with 10% γ-PGA reached 66% release after the same amount of time. The rate constant for the release kinetics showed that PVA with 5% γ-PGA had a higher value than that of the other samples, reaching saturation first.

COVID-19 contagion concern scale (PRE-COVID-19): Validation in Cuban patients with type 2 diabetes.

AIMS: It is important to have valid and reliable measures to determine the psychological impact of COVID-19 in patients with diabetes; however, few instruments have been developed and validated for this population. Therefore, the aim of this study was to validate the Scale of Worry for Contagion of COVID-19 (PRE-COVID-19) in a sample of patients with diabetes mellitus (DM). MATERIALS AND METHODS: A total of 219 patients (66.2% female, mean age 58.5 SD = 18.2) participated, selected through non-probabilistic sampling. The PRE-COVID-19 and the Generalized Anxiety Disorder Scale-2 were applied. Reliability analysis was performed for internal consistency, structural equation modeling and item response theory modeling. RESULTS: The results show that a unidimensional 5-item model presents satisfactory goodness-of-fit indices and excellent reliability values. Likewise, convergent validity between the PRE-COVID-19 and a measure of anxiety is evident. All items present adequate discrimination parameters, allowing for discerning between those patients with critical concern about COVID-19 contagion from those with severe concern. CONCLUSION: It is concluded that the PRE-COVID-19 is an instrument with adequate psychometric properties to measure concern about COVID-19 infection and the emotional impact in patients with DM.

Types of randomized clinical trials published in PubMed over 40 years / Tipos de ensayos clínicos con asignación aleatoria publicados en PubMed durante 40 años

Abstract Introduction: there are several variations of randomized clinical trials. Trials can be classi fied by design as parallel, cross-over, factorial, assignment by group, n-of-1, paired, withdrawal, adaptive and pragmatic; and by purpose as superiority, non-inferiority and equivalence. Given this heterogeneity, the Consolidated Standards of Reporting Trials (CONSORT) were introduced in 1996 to provide a guideline for reporting randomized clinical trials. Objective: to describe the publication tendency of the various types of randomized clinical trials over 40 years, with reference to the publication of CONSORT and its extensions. Methods: the PubMed tool was used to search for randomized clinical trials published between 1979 and 2018, classifying them according to the varieties described. Results: a total of 472,114 published articles were found; 90.2% did not report the type of design and 98.2% did not report the purpose. Among the articles that reported the variety of randomized clinical trial, the predominant design was cross-over (5.9%), followed by parallel groups (2.34%); while the most common purpose was superiority (0.84%). After the launch of CONSORT, there was an increased proportion of articles published with the following designs: parallel groups; difference in proportions 1.89 95% CI (1.1-2.7); paired 1.07 95% CI (0.2-1.9); and pragmatic 4.73 95% CI (4.4-5.1); and for the purpose of non-inferiority 5.97 95% CI (5.6-6.3). Discussion: most articles on randomized clinical trials do not mention their type in the title and abstract. The proportion of articles that did, increased slightly after CONSORT was published. (Acta Med Colomb 2021; 46. DOI:https://doi.org/10.36104/amc.2021.1884).

Resumen Introducción: existen múltiples variantes del ensayo clínico aleatorizado; según diseño: grupos paralelos, cruzado, factorial, asignación por grupos, N de 1, pareado, retiro, adaptativo y pragmático; y por propósito: superioridad, no inferioridad y equivalencia. Debido a esta heterogeneidad, en 1996 se introdujo el CONSORT (Consolidated Standards of Reporting Trials) para suministrar una guía para el reporte de los ensayos clínicos aleatorizados. Objetivo: describir la tendencia de publicación de los tipos de ensayos clínicos aleatorizados durante 40 años, en relación con la publicación del CONSORT y sus extensiones. Métodos: se utilizó la herramienta PubMed para realizar una búsqueda de ensayos clínicos aleatorizados publicados entre 1979 y 2018, discriminándolos según las variantes descritas. Resultados: se encontraron 472 114 artículos publicados, el 90.2% no reportó tipo de diseño y 98.2% no reportó propósito. Entre los artículos que reportaron la variante de ensayos clínicos aleatorizados, el diseño predominante fue el cruzado (5.9%), seguido por grupos paralelos (2.34%); mientras que el propósito más frecuente fue el de superioridad (0.84%). Hubo un aumento en la proporción de artículos por variante publicados después del lanzamiento del CONSORT para los diseños de: grupos paralelos; diferencia de proporciones 1.89 IC 95% (1.1-2.7); pareado 1.07 IC 95% (0.2-1.9); pragmático 4.73 IC 95% (4.4-5.1); y para el propósito de no inferioridad 5.97 IC 95% (5.6-6.3). Discusión: la mayoría de los artículos sobre ensayos clínicos aleatorizados no mencionan en su título y resumen la variante de estos. La proporción de artículos que sí lo hicieron, aumentó discre tamente después de la publicación del CONSORT. (Acta Med Colomb 2021; 46. DOI:https://doi.org/10.36104/amc.2021.1884).

Stem cells and COVID-19: are the human amniotic cells a new hope for therapies against the SARS-CoV-2 virus?

A new coronavirus respiratory disease (COVID-19) caused by the SARS-CoV-2 virus, surprised the entire world, producing social, economic, and health problems. The COVID-19 triggers a lung infection with a multiple proinflammatory cytokine storm in severe patients. Without effective and safe treatments, COVID-19 has killed thousands of people, becoming a pandemic. Stem cells have been suggested as a therapy for lung-related diseases. In particular, mesenchymal stem cells (MSCs) have been successfully tested in some clinical trials in patients with COVID-19. The encouraging results positioned MSCs as a possible cell therapy for COVID-19. The amniotic membrane from the human placenta at term is a valuable stem cell source, including human amniotic epithelial cells (hAECs) and human mesenchymal stromal cells (hAMSCs). Interestingly, amnion cells have immunoregulatory, regenerative, and anti-inflammatory properties. Moreover, hAECs and hAMSCs have been used both in preclinical studies and in clinical trials against respiratory diseases. They have reduced the inflammatory response and restored the pulmonary tissue architecture in lung injury in vivo models. Here, we review the existing data about the stem cells use for COVID-19 treatment, including the ongoing clinical trials. We also consider the non-cellular therapies that are being applied. Finally, we discuss the human amniotic membrane cells use in patients who suffer from immune/inflammatory lung diseases and hypothesize their possible use as a successful treatment against COVID-19.

24.0 kyr cal BP stone artefact from Vale da Pedra Furada, Piauí, Brazil: Techno-functional analysis.

Current archaeological paradigm proposes that the first peopling of the Americas does not exceed the Last Glacial Maximum period. In this context, the acceptance of the anthropogenic character of the earliest stone artefacts generally rests on the presence of projectile points considered no more as typocentric but as typognomonic, since it allows, by itself, to certify the human character of the other associated artefacts. In other words, without this presence, nothing is certain. Archaeological research at Piauí (Brazil) attests to a Pleistocene human presence between 41 and 14 cal kyr BP, without any record of lithic projectile points. Here, we report the discovery and interpretation of an unusual stone artefact in the Vale da Pedra Furada site, in a context dating back to 24 cal kyr BP. The knapping stigmata and macroscopic use-wear traces reveal a conception centred on the configuration of double bevels and the production in the same specimen of at least two successive artefacts with probably different functions. This piece unambiguously presents an anthropic character and reveals a technical novelty during the Pleistocene occupation of South America.

Características clínicas y epidemiológicas de la COVID-19 en pediatría en República Dominicana / Clinical and epidemiological characteristics of COVID-19 in Pediatrics in Dominican Republic

Introducción: En marzo del 2020 se detectó un brote de la enfermedad por nuevo coronavirus en La Romana, República Dominicana, desde entonces la enfermedad se ha esparcido rápidamente a nivel nacional. Objetivos: Describir la manifestaciones clínicas y epidemiológicas de la COVID-19 en menores de 18 años. Métodos: Se analizaron los datos extraídos del Sistema Nacional de Vigilancia Epidemiológica. Los análisis incluyen las características sociodemográficas, manifestaciones clínicas, tasas de letalidad y mortalidad, análisis geoespacial de diseminación viral y curva epidémica. Resultados: Hasta el 13 de julio de 2020 se registró un total de 46 301 casos, 3009 fueron pediátricos (6,4 por ciento) y de estos 2992 se confirmaron con la enfermedad (99,4 por ciento). La curva epidémica mostró un patrón de transmisión continua y de fuente común, con un pico de incidencia en la semana epidemiológica 27. La mayoría de los casos confirmados (50,7 por ciento) eran de sexo femenino, con un promedio de 9 años (rango 0-17, rango intercuartílico 4-14 años) y el 74,0 por ciento sintomático. La sintomatología más frecuente fue la fiebre (80,3 por ciento), cefalea (74,5 por ciento), mialgia (37,1 por ciento) y dificultad respiratoria (7,1 por ciento). La tasa de admisión a unidades de cuidado intensivo fue < 1 por ciento y la letalidad de 0,2. Conclusiones: La COVID-19 se ha diseminado rápidamente en niños de todo el país. A pesar de su baja letalidad, se deben fortalecer las estrategias de prevención para aplanar la curva de contagios y disminuir el impacto en grupos de mayor riesgo(AU)

Introduction: In March, 2020 it was detected an outbreak of the disease caused by the new coronavirus in La Romana, Dominican Republic, from that moment the disease has spreaded quickly trough all the country. Objectives: Describe the clinical and epidemiological manifestations of COVID-19 in patients under 18 years. Methods: There were analyzed the data from the National System of Epidemiological Surveillance. The analysis included the sociodemographic characteristics, clinical manifestations, lethality and mortality rates, geospatial analysis of viral spreading, and epidemic curve. Results: Until July 13th, 2020, it was registered a total of 46 301 cases, 3 009 were pediatric patients (6.4 percent) and of these 2 992 were confirmed with the disease (99.4 percent). The epidemic curve showed a continued transmission pattern and with a common source, with an incidence peak in the epidemiological week number 27. Most of the confirmed cases (50. 7 percent) were females, with a predominance of the one of 9 years old (range 0-17, intercuartilic range 4-14 years) and the 74.0 percent were symptomatic. The most common symptomatology was fever (80,3 percent), cephalalgia (74.5 percent), myalgia (37.1 percent) and respiratory difficulty (7.1 percent). The admittion rate in intensive care units was of < 1 percent and the lethality of 0.2. Conclusions: COVID-19 has spreaded quickly in children of all the country. Although the low lethality, the prevention strategies to flat the contagions curve must be strengthening and in that way it will be possible to decrease the impact in the groups of higher risk(AU)

Synthesis of ZnO Nanorod Film Deposited by Spraying with Application for Flexible Piezoelectric Energy Harvesting Microdevices.

Industry 4.0 and the Internet of Things have significantly increased the use of sensors and electronic products based on flexible substrates, which require electrical energy for their performance. This electrical energy can be supplied by piezoelectric vibrational energy harvesting (pVEH) devices. These devices can convert energy from ambient mechanical excitations into electrical energy. In order to develop, these devices require piezoelectric films fabricated with a simple and low-cost process. In this work, we synthesize ZnO nanorod film by a solvothermal method and deposit by spraying on ITO (indium-tin-oxide)/PET (polyethylene terephthalate) flexible substrate for a pVEH microdevice. The results of the characterization of the ZnO nanorod film using X-ray diffraction (XRD) confirm the typical reflections for this type of nanomaterial (JCPDS 36-145). Based on transmission electron microscopy (TEM) images, the size of the nanorod film is close to 1380 nm, and the average diameter is 221 ± 67 nm. In addition, the morphological characteristics of the ZnO nanorod film are obtained using atomic force microscopy (AFM) tapping images. The pVEH microdevice has a resonant frequency of 37 Hz, a generated voltage and electrical power of 9.12 V and 6.67 µW, respectively, considering a load resistance of 107.7 kΩ and acceleration of 1.5 g. The ZnO nanorod film may be applied to pVEH microdevices with flexible substrates using a low-cost and easy fabrication process.

Crosstalk between estradiol and NFκB signaling pathways on placental leptin expression.

Pregnancy success requires a proper fetal maternal interaction at the establishment of implantation. Leptin has been described as a multitasking cytokine in pregnancy, particularly in the placenta, where it acts as an autocrine hormone. The expression of leptin in normal trophoblastic cells is regulated by different endogenous signals. We have previously reported that 17ß-estradiol upregulates placental leptin expression through genomic and non-genomic mechanisms. To improve the knowledge of estrogen receptor mechanisms in regulating leptin gene expression, we examined transcription nuclear factor kappa B (NFκB) effect on estradiol leptin induction in human BeWo cell line and human term placental explants. We demonstrated that estradiol induction effect on leptin expression is blocked by the inhibition of NFκB signaling. We also found that the overexpression of p65 subunit, the active form of NFκB, induces leptin expression. Moreover, downregulation of estrogen receptor alpha (ERα), through a specific siRNA, abolished NFκB effect on leptin expression. We also demonstrated that ERα enhanced NFκB signaling pathway activation in trophoblastic cells. Estradiol treatment significantly increased p65 expression and phosphorylation of the inhibitory protein κB alpha (IκBα). A reporter plasmid containing NFκB elements was also induced in response to estradiol stimulation. Localization experiments revealed that estradiol treatment induced nuclear localization of overexpressed p65. Moreover, the overexpression of ERα produced a complete displacement of p65 protein to the nucleus. Finally, immunoprecipitation experiments showed the presence of a complex containing ERα and NFκB. All these evidences suggest a cooperative behavior between ERα and NFκB transcription factors to induce leptin transcription.

Larval fish assemblages in nearshore waters of southeast Gulf of California: vertical and temporal patterns

The influence of salinity and temperature on larval fish assemblages, as well as, temporal and vertical patterns on larval fish assemblages off the inlet of the Presidio River, southeast coast of the Gulf of California were evaluated. Samplings for ichthyoplankton and environmental parameter measurements were carried out at three depths, in five sampling sites, during September and December 1994, and April and June 1995. Anchovies and herrings (Clupeiformes) were the most abundant larval fish accounting for 77% of the total abundance. A significant relationship between salinity and the abundance of larval herrings (Opisthonema medirastre and O. dovii) and between the water temperature and the abundance of the weakfish (Cynoscion reticulatus) was found. Anchovies (Anchoa lucida, A. walkeri, and A. nasus) were present in all sampled months, while O. medirastre and O. dovii occurred in December and June, and C. reticulatus in September. Larvae of pelagic fish were more abundant near the surface, while larvae of demersal fish were more abundant near the bottom. The present study, by emphasising the importance of considering temporal and vertical changes in larval fish assemblages in coastal environments with ecological and economic importance, will be useful for designing more efficient sampling programs.(AU)

Se evaluó la influencia de la salinidad y la temperatura, así como patrones temporales y verticales en la comunidad de larvas de peces enfrente del río Presidio, costa sudeste del Golfo de California. Los muestreos de ictioplancton y las mediciones de los parámetros ambientales fueron realizados a tres profundidades, en cinco sitios de muestreo, durante septiembre y diciembre de 1994, y abril y junio de 1995. Las anchoas y sardinas (Clupeiformes) fueron las larvas de peces más abundantes representando el 77% de la abundancia total. Se encontró una relación significativa entre la salinidad y la abundancia de larvas de sardinas (Opisthonema medirastre and O. dovii), y entre la temperatura del agua y la abundancia de la corvina rayada (Cynoscion reticulatus). Las anchoas (Anchoa lucida, A. walkeri y A. nasus) estuvieron presentes en todos los meses muestreados, mientras que O. medirastre y O. dovii ocurrieron en diciembre y junio, y C. reticulatus en septiembre. Las larvas de peces pelágicos fueron más abundantes cerca de la superficie, mientras que las larvas de peces demersales fueron más abundantes cerca del fondo. El presente estudio, al enfatizar la importancia de considerar los cambios temporales y verticales en el ensamblaje de larvas de peces en ambientes costeros con importancia ecológica y económica, será útil para diseñar programas de muestreo más eficientes.(AU)