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BACKGROUND: Antimicrobial resistance is a global public health problem. Root canal microbiota associated with apical periodontitis represents a well-known reservoir of antimicrobial resistance genes (ARGs). However, the effect of type 2 diabetes mellitus (T2DM) in this reservoir is unknown. This study aimed to establish if root canal microbiota associated with apical periodontitis in T2DM patients is an augmented reservoir by identifying the prevalence of nine common ARGs and comparing it with the prevalence in nondiabetic patients. METHODOLOGY: This cross-sectional study included two groups: A T2DM group conformed of 20 patients with at least ten years of living with T2DM and a control group of 30 nondiabetic participants. Premolar or molar teeth with pulp necrosis and apical periodontitis were included. A sample was collected from each root canal before endodontic treatment. DNA was extracted, and ARGs were identified by polymerase chain reaction. RESULTS: tetW and tetM genes were the most frequent (93.3 and 91.6%, respectively), while ermA was the least frequent (8.3%) in the total population. The distribution of the ARGs was similar in both groups, but a significant difference (p<0.005) was present in ermB, ermC, cfxA, and tetQ genes, being more frequent in the T2DM group. A total of eighty percent of the T2DM patients presented a minimum of four ARGs, while 76.6% of the control group presented a maximum of three. CONCLUSIONS: Root canal microbiota associated with apical periodontitis in T2DM patients carries more ARGs. Therefore, this pathological niche could be considered an augmented reservoir.
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Diabetes Mellitus Tipo 2 , Microbiota , Periodontitis Periapical , Humanos , Antibacterianos , Cavidad Pulpar , Estudios Transversales , Farmacorresistencia Bacteriana , Tratamiento del Conducto Radicular , Periodontitis Periapical/terapia , Microbiota/genéticaRESUMEN
The colonization of land by a single streptophyte algae lineage some 450 million years ago has been linked to multiple key innovations such as three-dimensional growth, alternation of generations, the presence of stomata, as well as innovations inherent to the birth of major plant lineages, such as the origins of vascular tissues, roots, seeds and flowers. Multicellularity, which evolved multiple times in the Chloroplastida coupled with precise spatiotemporal control of proliferation and differentiation were instrumental for the evolution of these traits. RETINOBLASTOMA-RELATED (RBR), the plant homolog of the metazoan Retinoblastoma protein (pRB), is a highly conserved and multifunctional core cell cycle regulator that has been implicated in the evolution of multicellularity in the green lineage as well as in plant multicellularity-related processes such as proliferation, differentiation, stem cell regulation and asymmetric cell division. RBR fulfills these roles through context-specific protein-protein interactions with proteins containing the Leu-x-Cys-x-Glu (LxCxE) short-linear motif (SLiM); however, how RBR-LxCxE interactions have changed throughout major innovations in the Viridiplantae kingdom is a question that remains unexplored. Here, we employ an in silico evo-devo approach to predict and analyze potential RBR-LxCxE interactions in different representative species of key Chloroplastida lineages, providing a valuable resource for deciphering RBR-LxCxE multiple functions. Furthermore, our analyses suggest that RBR-LxCxE interactions are an important component of RBR functions and that interactions with chromatin modifiers/remodelers, DNA replication and repair machinery are highly conserved throughout the Viridiplantae, while LxCxE interactions with transcriptional regulators likely diversified throughout the water-to-land transition.
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Neoplasias de la Retina , Retinoblastoma , Animales , Proteína de Retinoblastoma/metabolismo , Diferenciación CelularRESUMEN
Crop wild relatives (CWR) intra- and interspecific diversity is essential for crop breeding and food security. However, intraspecific genetic diversity, which is central given the idiosyncratic threats to species in landscapes, is usually not considered in planning frameworks. Here, we introduce an approach to develop proxies of genetic differentiation to identify conservation areas, applying systematic conservation planning tools that produce hierarchical prioritizations of the landscape. It accounts for: (i) evolutionary processes, including historical and environmental drivers of genetic diversity, and (ii) threat processes, considering taxa-specific tolerance to human-modified habitats, and their extinction risk status. Our analyses can be used as inputs for developing national action plans for the conservation and use of CWR. Our results also inform public policy to mitigate threat processes to CWR (like crops living modified organisms or agriculture subsidies), and could advise future research (e.g. for potential germplasm collecting). Although we focus on Mesoamerican CWR within Mexico, our methodology offers opportunities to effectively guide conservation and monitoring strategies to safeguard the evolutionary resilience of any taxa, including in regions of complex evolutionary histories and mosaic landscapes.
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Conservación de los Recursos Naturales , Fitomejoramiento , Humanos , Productos Agrícolas/genética , Agricultura/métodos , Evolución BiológicaRESUMEN
The information about where crops are distributed is useful for agri-environmental assessments, but is chiefly important for food security and agricultural policy managers. The quickness with which this information becomes available, especially over large areas, is important for decision makers. Methodologies have been proposed for the study of crops. Most of them require field survey for ground truth data and a single crop map is generated for the whole season at the end of the crop cycle and for the next crop cycle a new field survey is necessary. Here, we present models for recognizing maize (Zea mays L.), beans (Phaseolus vulgaris L.), and alfalfa (Medicago sativa L.) before the crop cycle ends without current-year field survey for ground truth data. The models were trained with an exhaustive field survey at plot level in a previous crop cycle. The field surveys begin since days before the emergence of crops to maturity. The algorithms used for classification were support vector machine (SVM) and bagged tree (BT), and the spectral information captured in the visible, red-edge, near infrared, and shortwave infrared regions bands of Sentinel 2 images was used. The models were validated within the next crop cycle each fifteen days before the mid-season. The overall accuracies range from 71.9% (38 days after the begin of cycle) to 87.5% (81 days after the begin cycle) and a kappa coefficient ranging from 0.53 at the beginning to 0.74 at mid-season.
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Productos Agrícolas , Zea mays , Agricultura , Algoritmos , Aprendizaje Automático , Medicago sativaRESUMEN
Pure CaMgSi was successfully synthesized by mechanical milling, followed by spark plasma sintering. Rietveld refinement was used to calculate the structural parameters, where a crystallite size (D XRD) of 79 nm was estimated. This value was confirmed by the Williamson-Hall analysis. Transmission electron microscopy was used to analyze the microstructure, revealing the presence of extensive interfaces, nanoparticles, and a high crystallinity. First-principles calculations were performed with the WIEN2k package, finding a band gap of 0.27 eV. The thermoelectric properties were determined combining experimental measurements and theoretical results from the BoltzTraP code. The highest value of the electronic figure of merit (ZT e) was 1.67 at 415 K. However, when the lattice thermal contribution (k L) is considered, the highest value of the figure of merit (ZT) was 0.144 at 644 K.
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Esports has seen a phenomenal explosion in popularity in recent years, gaining increasing interest from the media, sports, and technology industries. The purpose of this study is to show an overview of the recent evolution of the gaming market in representative countries in Eastern Asia, Western Europe, and North America during 2017-2019, and the corresponding growth projections for the next five years. For this purpose, descriptive, correlational, and forecasting analyses were used to assess the relationships among key variables associated with the growth of the gaming industry and to show different possibilities to address the data using data analytics. The games market revenues, total number of players, Google trends data, GDP per capita and online population were studied as possible key influencers to explain the industry's growth. Predictive analytics with MS Power BI revealed a positive correlation between GDP per capita and market revenues and players in European and North American countries, while in Asia was just the opposite. Also, a positive relationship between Google trends in esports and the games market revenues is noted. Forecasts showed significant growth for each region. Practical implications and future research directions are discussed.
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Climate change is causing detrimental changes in living organisms, including pathogens. This review aimed to determine how climate change has impacted livestock system management, and consequently, what factors influenced the gastrointestinal nematodes epidemiology in small ruminants under tropical conditions. The latter is orientated to find out the possible solutions responding to climate change adverse effects. Climate factors that affect the patterns of transmission of gastrointestinal parasites of domesticated ruminants are reviewed. Climate change has modified the behavior of several animal species, including parasites. For this reason, new control methods are required for controlling parasitic infections in livestock animals. After a pertinent literature analysis, conclusions and perspectives of control are given.
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Abstract Antimicrobial resistance is a global public health problem. Root canal microbiota associated with apical periodontitis represents a well-known reservoir of antimicrobial resistance genes (ARGs). However, the effect of type 2 diabetes mellitus (T2DM) in this reservoir is unknown. This study aimed to establish if root canal microbiota associated with apical periodontitis in T2DM patients is an augmented reservoir by identifying the prevalence of nine common ARGs and comparing it with the prevalence in nondiabetic patients. Methodology This cross-sectional study included two groups: A T2DM group conformed of 20 patients with at least ten years of living with T2DM and a control group of 30 nondiabetic participants. Premolar or molar teeth with pulp necrosis and apical periodontitis were included. A sample was collected from each root canal before endodontic treatment. DNA was extracted, and ARGs were identified by polymerase chain reaction. Results tetW and tetM genes were the most frequent (93.3 and 91.6%, respectively), while ermA was the least frequent (8.3%) in the total population. The distribution of the ARGs was similar in both groups, but a significant difference (p<0.005) was present in ermB, ermC, cfxA, and tetQ genes, being more frequent in the T2DM group. A total of eighty percent of the T2DM patients presented a minimum of four ARGs, while 76.6% of the control group presented a maximum of three. Conclusions Root canal microbiota associated with apical periodontitis in T2DM patients carries more ARGs. Therefore, this pathological niche could be considered an augmented reservoir.
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Angiogenesis, the formation of new blood vessels, underlies tissue development and repair. Some medicinal plant-derived compounds can modulate the angiogenic response. Heliopsis longipes, a Mexican medicinal plant, is widely used because of its effects on pain and inflammation. The main bioactive phytochemicals from H. longipes roots are alkamides, where affinin is the most abundant. Scientific studies show various medical effects of organic extracts of H. longipes roots and affinin that share some molecular pathways with the angiogenesis process, with the vasodilation mechanism of action being the most recent. This study investigates whether pure affinin and the ethanolic extract from Heliopsis longipes roots (HLEE) promote angiogenesis. Using the aortic ring rat assay (ex vivo method) and the direct in vivo angiogenesis assay, where angioreactors were implanted in CD1 female mice, showed that affinin and the HLEE increased vascular growth in a dose-dependent manner in both bioassays. This is the first study showing the proangiogenic effect of H. longipes. Further studies should focus on the mechanism of action and its possible therapeutic use in diseases characterized by insufficient angiogenesis.
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Asteraceae/química , Etanol/química , Neovascularización Fisiológica/efectos de los fármacos , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Alcamidas Poliinsaturadas/farmacología , Animales , Aorta Torácica/efectos de los fármacos , Estructura Molecular , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Raíces de Plantas/química , Plantas Medicinales , Alcamidas Poliinsaturadas/química , Alcamidas Poliinsaturadas/aislamiento & purificación , RatasRESUMEN
BACKGROUND: In some regions of Mexico, edible wild plants have been displaced or eliminated from the traditional food systems, mainly by changes in land use, booming monoculture, herbicide use, and by changes among the new generations in the traditional foods and diets of indigenous populations. In the Totonacapan region of Puebla, the gradual change from the traditional acahual plantation to coffee-type agroecosystems has provoked the displacement of old-growth forests and the eradication of wild plants since 1970. One of the wild species which has been used in traditional medicine and food recipes by the Totonac culture is Smilax aristolochiifolia (SMILACACEAE), known as "kgentsililh". This species forms part of traditional Totonac recipes, in which the tender stems are still used in local medicine to treat menstrual pain, deal with dysentery, and prevent hair loss. According to the Maxent® Program, there are still potential areas with habitats suitable to promote its conservation in the Poblano Totonacapan. METHODS: We conducted 260 interviews with people in 13 locations in the northern Sierra of the State of Puebla. Variables taken into account in the interview related to the consumption frequency of the species, its abundance and distribution perception, reasons or arguments given by the Totonac indigenous population about the decreased presence of specimens of S. aristolochiifolia, its dates of collection, and the cutting prices of kgentsililh at the community level and in local markets. The relative abundance of S. aristolochiifolia was determined through 22 samples in 2ts of 600 m2. Later, its potential distribution in the state of Puebla was estimated using the Maxent® Program Ver. 3.3.3. RESULTS: Of the 260 Totonac families interviewed, 31% had stopped consuming kgentsililh. The residents reported that in the last 50 years the populations of this plant had diminished in the northern Sierra of the State of Puebla, mainly due to changes in land use, herbicide application, over-collection, and urban growth. In traditional medicine, the stem sap of S. aristolochiifolia is currently employed to help treat baldness, and the "tuberous root" or plant rhizome is used to prepare a tea infusion to treat dysentery. The cost of plant guides varies from 10.00 to 40.00 Mexican pesos for one bunch (around 0.5 to 2.00 US dollars), and every bundle consists of between 7 to 10 cuttings from 0.4 to 0.5 m long. From our 22 quadrats of sampling and collection of S. aristolochiifolia, we were able to recognize a total of 32 specimens. There is a considerable abundance of kgentsililh in acahual plantations and old-growth forests (evergreen lowland and mid-elevation perennial forest) concerning the coffee-type plantations and milpas. According to our analysis using the Maxent Program®, eight physical and climatic variables have a direct relationship to the potential distribution of the species. CONCLUSIONS: Smilax aristolochiifolia is still a plant of socioeconomic importance, mainly because of its food value and its use in traditional medicine by indigenous families in Poblano Totonacapan. It is evident that the villagers perceive that in the last 50 years the species has decreased its population mainly due to land-use change, the application of herbicides to the different family production units, and climate change. At the moment, there is no knowledge about the methods of propagation of the species, and therefore there is no intention on the part of the population to conserve the species. However, it would be of great importance to generate a biocultural conservation strategy and take advantage of the results obtained from the potential geographic distribution area, since according to the Maxent® Program, there are still potential areas with habitat suitable to promote conservation in Poblano Totonacapan.
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Smilax , Ecosistema , Humanos , México , Dispersión de las Plantas , Plantas Comestibles , Plantas MedicinalesRESUMEN
Nowadays, it is very important to study and propose new mechanisms for generating electricity that are environmentally friendly, in addition to using renewable resources. Thermoelectric (TE) devices are fabricated with materials that can convert a temperature difference into electricity, without the need for rotating parts. In this work, we report the TE properties of rhenium carbonitride (ReCN) as an important feature of a hard and thermodynamically stable material of band gap Δg = 0.626 eV. We use the electronic band structure behavior near the Fermi energy with the Seebeck coefficient to estimate the figure of merit ZT based on Boltzmann transport theory to characterize this property. Our results show that this compound has interesting TE properties among 300 and 1200 K for p- and n-type doping.
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Resumen Objetivo La dehiscencia anastomótica (DA) en cirugía colorrectal es una de las complicaciones más devastadoras. El empleo de la angiografía de fluorescencia con verde de indocianina, se ha introducido en este campo como una herramienta prometedora para reducir la incidencia de DA. El objetivo de este estudio es valorar en nuestro medio, los resultados de la introducción de esta técnica en cuanto a prevención de DA. Materiales y Método: Se llevó a cabo un estudio prospectivo, incluyendo 59 pacientes sometidos a cirugía colorrectal resectiva a los que se les realizó una evaluación mediante angiografía con verde de indocianina intraoperatoria de la vascularización anastomótica. Resultados: Tras la aplicación de la técnica, se modificó el punto de sección en 9 pacientes (15,25%); en los cuales no se registró ninguna DA. La tasa de complicaciones global fue de 35,59% (n = 21) objetivando 3 dehiscencias anastomóticas en la serie. Conclusión: Esta técnica se perfila como una estrategia adicional en la prevención de la aparición de DA. Serán necesarios estudios randomizados con inclusión de mayor número de pacientes para obtener resultados concluyentes.
Aim: Anastomotic leakage (AL) following colorectal surgery is one of the most devastating complication. The use of indocyanine green fluorescence angiography has been developed as a promising tool to reduce the incidence of AL. The aim of this study is to evaluate the impact of this technique on the prevention of AL. Materials and Method: A prospective study was carried out, including 59 patients undergoing resective colorectal surgery. It was performed intraoperatively indocyanine green angiography evaluation of the anastomotic perfusión in all of then. Results: The section point was modified in 9 patients (15.25%); in which no AL was registered. The overall complication rate was 35.59% (n = 21), founding 3 anastomotic dehiscences in the serie. Conclusion: In conclusion, in our experience this technique is an additional strategy in the prevention of the AL. Randomized control trial including more patients will be necessary to obtain conclusive results.
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Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Dehiscencia de la Herida Operatoria/prevención & control , Dehiscencia de la Herida Operatoria/terapia , Angiografía con Fluoresceína/métodos , Cirugía Colorrectal/efectos adversos , Fuga Anastomótica/prevención & control , Verde de Indocianina/uso terapéutico , España , Dehiscencia de la Herida Operatoria/complicaciones , Angiografía con Fluoresceína/efectos adversos , Estudios Prospectivos , Resultado del Tratamiento , Fuga Anastomótica/mortalidad , Fuga Anastomótica/terapiaRESUMEN
Introducción: El consumo de tabaco es perjudicial para la salud, según la Organización Mundial de la Salud (OMS) el tabaquismo es la causa de muerte de aproximadamente 8 millones de personas cada año. Objetivo: El propósito de la investigación fue determinar los factores asociados al consumo de tabaco en estudiantes universitarios de Lima Metropolitana. Métodos: La muestra estuvo conformada por 447 estudiantes de diferentes universidades de Lima, se aplicó una encuesta previamente validada: Test de Fagerstrom para medir el consumo de tabaco. Posteriormente los datos fueron analizados utilizando tablas de distribución, frecuencias y contingencia. Además, se aplicó la prueba estadística de regresión para obtener las razones de prevalencias (RP) de las variables de estudio tanto en el análisis bivariado como en el multivariado, con un intervalo de confianza al 95% (IC al 95%). Resultados: Se evidenció que existe asociación significativa entre el sexo masculino y el hábito de fumar (p=0,01), con un RP = 1,67 e IC al 95% = [1,03 2,23]. También se pudo observar que tener padres fumadores estuvo estadísticamente asociado al hábito tabáquico en los universitarios, con un valor de p=0,00, y un RP = 2,53 con IC al 95% = [1,62 3,52]. No se encontró asociación significativa entre las variables edad y presión social. Conclusión: Las variables sexo y padres fumadores tienen asociación significativa con el consumo de tabaco enfatizando que tanto nuestro entorno familiar como académico merece ser seguro, saludable y libre del humo de tabaco.
Introduction: Tobacco use is harmful to health, according to the World Health Organization (WHO) smoking is the cause of death for approximately 8 million people each year. Objective: The purpose of the research was to determine the factors associated with tobacco consumption in university students from Metropolitan Lima. Methods: The sample consisted of 447 students from different universities in Lima, a previously validated survey was applied: Fagerstrom test to measure tobacco consumption. Subsequently, the data was analyzed using distribution, frequency and contingency tables. In addition, regression statistical test was applied to obtain the prevalence ratios (PR) of the study variables in both bivariate and multivariate analyzes, with a 95% confidence interval (95% CI). Results: It was evidenced that there is a significant association between male sex and smoking (p = 0.01), with an RP = 1,67 and 95% CI = [1,03 2,23]. It was also observed that having smoking parents was statistically associated with smoking in university students, with a value of p=0.00, and an RP=2,53 with a 95% CI = [1,62 3,52]. No significant association was found between the variables age and social pressure. Conclusion: The variables sex and smoking parents have a significant association with tobacco consumption, emphasizing that both our family and academic environment deserve to be safe, healthy and free of tobacco smoke.
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Introducción: la Montanoa tomentosa es un recurso fitogenético con propiedades medicinales utilizado en México. A pesar de su relevancia botánica, la información específica de las distribuciones de taxones infraespecíficos y la los factores que influyen en su desarrollo aún son limitados. Objetivo: Informar el potencial geográfico distribución y las variables ambientales asociadas a nichos ecológicos de dos subespecies de M. tomentosa (M. tomentosa subsp. Tomentosa y M. tomentosa subsp. Xanthiifolia) en territorio mexicano. Métodos: A Se creó una base de datos de registros de herbario, se realizó una búsqueda sistemática in situ de ambas subespecies desde Octubre de 2015 a marzo de 2016, durante la temporada de floración y fructificación. Posteriormente, recorridos exploratorios (Guanajuato, Querétaro, Hidalgo, Ciudad de México, Estado de México, Puebla, Oaxaca y Chiapas). Un total de 181 Se muestrearon y georreferenciaron individuos, generando nuevos registros para la actualización de la base de datos. Tres hábitat modelos de idoneidad (complejo M. tomentosa, M. tomentosa subsp. tomentosa y M. tomentosa subsp. xanthiifolia) se generaron utilizando el software MaxEnt. Este software estima la probabilidad de distribución de especies. utilizando datos georreferenciados y características ambientales como predictores, mediante el logaritmo de entropía máxima y el método bayesiano. Resultados: De 22 variables ambientales utilizadas como predictores, cinco (estacionalidad de temperatura, isotermalidad, temperatura máxima del mes más cálido, precipitación del más cálido trimestre y precipitación del trimestre más húmedo) contribuyeron con el 70,2% de la contribución porcentual total. los El modelo mostró una distribución potencial de 77 688 km2, aproximadamente el 4% del territorio de la República Mexicana. Ambos La subespecie creció entre 500 y 2 500 m. Se asociaron a vegetación xerófila y heliófila, a veces también estaban ubicadas en la periferia o incrustadas en aberturas de bosques templados y subhúmedos. No estuvieron presentes regiones secas del norte del país. Conclusiones: estacionalidad de la temperatura, isotermalidad y la temperatura máxima del mes más cálido determinan la distribución de la especie. Precipitación del cuarto más cálido y la precipitación del cuarto más húmedo define el hábitat entre M. tomentosa subsp. tomentosa y M. tomentosa subsp. xanthiifolia. Estos hallazgos aclaran las preferencias ecológicas y la delimitación los taxones infraespecíficos de M. tomentosa.
Introduction: Montanoa tomentosa is a phytogenetic resource with medicinal properties used in Mexico. Despite its botanic relevance, the specific information of infraespecific taxa distributions and the environmental factors that influence their development is still limited. Objective: To report the potential geographic distribution and the environmental variables associated to ecological niches of two subspecies of M. tomentosa (M. tomentosa subsp. tomentosa and M. tomentosa subsp. xanthiifolia) in the Mexican territory. Methods: A database of herbarium records was created, an in situ systematic search of both subspecies was carried out from October 2015 to March 2016, during the flowering-fruiting season. After that, exploratory tours (Guanajuato, Querétaro, Hidalgo, Mexico City, State of Mexico, Puebla, Oaxaca and Chiapas) were realized. A total of 181 individuals were sampled and georeferenced, generating new records for the database upgrading. Three habitat suitability models (M. tomentosa complex, M. tomentosa subsp. tomentosa and M. tomentosa subsp. xanthiifolia) were generated using the MaxEnt software. These software estimates the probability of species distribution using geo-referenced data and environmental characteristics as predictors, through the maximum entropy logarithm and the Bayesian method. Results: From 22 environmental variables used as predictors, five (seasonality of temperature, isothermality, maximum temperature of the warmest month, precipitation of the warmest trimester and precipitation of the wettest trimester) contributed 70.2 % of the total percentage contribution. The model showed a potential distribution of 77 688 km2, approximately 4 % of the Mexican Republic territory. Both subspecies grew between 500 and 2 500 m. They were associated to xerophilous and heliophiles vegetation, sometimes they were located in the periphery or embed in openings of temperate and sub-humid forests too. They were not present dry regions from the North of the country. Conclusions: Temperature seasonality, isothermality and maximum temperature of the warmest month determine the distribution of the species. Precipitation of the warmest quarter and precipitation of wettest quarter defines the habitat between M. tomentosa subsp. tomentosa and M. tomentosa subsp. xanthiifolia. These findings clarify the ecological preferences and delimitation the infraspecific taxa of M. tomentosa.
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Montanoa/clasificación , Plantas Medicinales , Ecosistema , MéxicoRESUMEN
La Organización Mundial de la Salud define al tabaquismo como una enfermedad adictiva crónica muy extendida a nivel mundial. Representa una de las mayores amenazas para la salud púbica, afectando a niños, jóvenes y adultos. Se calcula que existen 1.300 millones de fumadores en el mundo y alrededor del 80% de estos viven en países en los que existe una alta tasa de morbilidad y mortalidad asociada al tabaco principalmente en consumidores adultos. De manera particular, el consumo de tabaco ente jóvenes universitarios es evidente y preocupante. Diferentes autores en el mundo han planteado factores para el consumo de tabaco entre adolescentes y adultos jóvenes. Tales estudios sostienen que el hábito de fumar inicia, por lo general, durante la adolescencia y se consolida en la etapa universitaria. Además, el tabaquismo en progenitores, familiares y amigos es un factor, quizás el más destacable, que se asocia a la adquisición del hábito tabáquico.
The World Health Organization defines smoking as a chronic addictive disease widespread worldwide. It represents one of the greatest threats to public health, affecting children, youth and adults. It is estimated, that there are 1.300 million smokers in the world and about 80% of these live in countries where there is a high rate of morbidity and mortality associated with tobacco mainly in adult consumers. In particular, the consumption of tobacco among young university students is evident and worrisome. Different authors in the world have raised factors for tobacco use among adolescents and young adults. Such studies argue that the habit of smoking usually begins during adolescence and consolidates in the university stage. Smoking in parents, relatives, and friends is a factor, perhaps the most remarkable, which is associated with the acquisition of smoking as a habit.
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Introducción: Los implantes dentales deben transmitir esfuerzos al tejido óseo y generar deformaciones que favorezcan el equilibrio entre los procesos de formación y reabsorción ósea. Debido al alto número de pacientes que presentan maxilares con dimensiones reducidas, es necesario estudiar el comportamiento biomecánico de implantes dentales cortos. Objetivos: Evaluar el efecto de los parámetros de diseño: diámetro máximo, longitud de la interfaz hueso-implante y altura del filete de la rosca sobre el comportamiento biomecánico de un nuevo diseño de implante dental corto. Métodos: Los modelos tridimensionales del implante dental corto fueron creados usando el software Autodesk Inventor Profesional versión 2011 (Autodesk Inc, California, USA) y analizados con el software de elementos finitos Autodesk® Algor® Simulation (Autodesk Inc, California, USA). Resultados: Los niveles máximos de esfuerzos equivalentes de von Mises se obtuvieron, en el hueso cortical peri-implantar. Las cargas aplicadas al implante generaron, en el hueso trabecular peri-implantar, los mayores esfuerzos equivalentes de von Mises en la región apical y los menores valores en la región próxima al hueso cortical. Además, los mayores valores de deformación se obtuvieron en el hueso trabecular para todos los modelos estudiados. Conclusiones: En general, los resultados de las simulaciones mostraron que la mayoría de los modelos estudiados generan esfuerzos y deformaciones en el hueso cortical peri-implantar en niveles que estimulan el crecimiento y la remodelación ósea. No obstante, en algunas de las variantes simuladas se observaron niveles de esfuerzos y deformaciones, en zonas del hueso trabecular peri-implantar, que pueden provocar pérdida ósea en los maxilares. Las variables diámetro del implante y altura del filete de la rosca exhibieron la mayor influencia sobre los esfuerzos y deformaciones máximas generados en el tejido óseo(AU)
Introduction: Dental implants should transmit stresses to the bone tissue and generate strain levels that favor the balance between the bone formation and bone resorption processes. Due to the high number of patients with reduced jawbone dimensions, it is essential to study the biomechanical behavior of short dental implants. Objective: Evaluate the effect of the design parameters: Maximum diameter, Length of the bone-implant interface and Thread depth on the biomechanical behavior of a new design of short dental implant. Methods: The 3D models of the short dental implant were created using Autodesk Inventor Professional software (Autodesk Inc, California, USA) and analyzed by finite elements with Autodesk® Algor® Simulation software (Autodesk Inc, California, USA). Results: The maximum von Mises equivalent stress was obtained in peri-implant cortical bone. The loads applied to the implant generated in peri-implant cancellous bone, the highest von Mises equivalent stress in the lower end of the apical region and the lowest stress values in the region next to the cortical bone. In addition, the highest strain values were obtained in cancellous bone for all models under study. Conclusions: In general, the simulation results showed that most of the models under study generate stresses and strains in peri-implant cortical bone at levels that stimulate bone growth and bone remodeling. However, for some models, it was observed levels of stress and strain in peri-implant cancellous bone that could provoke the bone onset. The variables Implant diameter and Thread depth exhibited the greatest influence on the maximum stresses and strains obtained in the bone tissue(AU)
Asunto(s)
Humanos , Masculino , Femenino , Fenómenos Biomecánicos/fisiología , Implantes Dentales/normas , Diseño de Implante Dental-PilarRESUMEN
Heliopsis longipes roots have been widely used in Mexican traditional medicine to relieve pain, mainly, toothaches. Previous studies have shown that affinin, the major alkamide of these roots, induces potent antinociceptive and anti-inflammatory activities. However, the effect of H. longipes root extracts and affinin on the cardiovascular system have not been investigated so far. In the present study, we demonstrated that the dichloromethane and ethanolic extracts of H. longipes roots, and affinin, isolated from these roots, produce a concentration-dependent vasodilation of rat aorta. Affinin-induced vasorelaxation was partly dependent on the presence of endothelium and was significantly blocked in the presence of inhibitors of NO, H2S, and CO synthesis (NG-nitro-l-arginine methyl ester (l-NAME), dl-propargylglycine (PAG), and chromium mesoporphyrin (CrMP), respectively); K⺠channel blockers (glibenclamide (Gli) and tetraethyl ammonium (TEA)), and guanylate cyclase and cyclooxygenase inhibitors (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and indomethacin (INDO), respectively). Our results demonstrate, for the first time, that affinin induces vasodilation by mechanisms that involve gasotransmitters, and prostacyclin signaling pathways. These findings indicate that this natural alkamide has therapeutic potential in the treatment of cardiovascular diseases.
Asunto(s)
Amidas/aislamiento & purificación , Amidas/farmacología , Asteraceae/química , Epoprostenol/metabolismo , Gasotransmisores/metabolismo , Transducción de Señal/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Amidas/química , Animales , Aorta/efectos de los fármacos , Aorta/fisiología , AMP Cíclico/metabolismo , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiología , Indometacina/farmacología , Masculino , Cloruro de Metileno , Modelos Biológicos , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Raíces de Plantas/química , Alcamidas Poliinsaturadas , Canales de Potasio/metabolismo , Ratas WistarRESUMEN
ResumenLos especímenes silvestres de Vanilla planifolia G. Jack forman parte del acervo genético primario, los cuales solo se han reportado en Oaxaca, México. Por ello se evaluó la distribución de esta especie con el objetivo de ubicar y describir características ecológicas en zonas potenciales de distribución. La metodología empleada consistió de cuatro etapas: 1) Elaboración de una base de datos con registros de herbario;2) Construcción de la distribución potencial basado en los registros históricos de herbario para la especie, mediante el modelo de máxima entropía (Maxent), con el uso de 22 variables bioclimáticas como predictoras; 3) Realización de búsquedas sistemáticas de individuos in situ con base en los registros de herbario y las áreas de distribución potencial en 24 municipios, para conocer la situación y la distribución del hábitat actual, y 4) Descripción mediante factores ambientales de los nichos ecológicos potenciales generados por MaxEnt. La revisión de las colecciones de herbarios reportó un total de 18 registros de V. planifolia, comprendidos entre 1939 y 1998.La búsqueda sistemática de individuos en campo ubicó 28 plantas distribuidas en 12 sitios sobre 95 364 Km2. Las variables que contribuyeron con mayor valor porcentual para determinar la estimación del modelo de distribución potencial en vainilla son precipitación del periodo más lluvioso (61.9 %), régimen de humedad del suelo (23.4 %) y precipitación del cuatrimestre más lluvioso (8.1 %). El hábitat potencial de la especie se distribuyó en cuatro zonas; trópico húmedo del golfo de México, templado húmedo, trópico húmedo y templado húmedo del pacifico. La precipitación anual osciló de 2 500 a 4 000 mm, con lluvias en verano y porcentaje de precipitación invernal de 5 a 10 %. El régimen de humedad y clima predominantes fueron údico tipo I (330 a 365 días de humedad) y cálido húmedo (Am/A(C) m). Las plantas se ubicaron en altitudes de 200 a 1 190 msnm, en laderas accidentadas, que por lo general están al pie de sistemas montañosos de 1 300 a 2 500 metros de altitud. En condiciones naturales la distribución de la especie no se limita a selva alta perennifolia, dado que se ubicó en bosque mesófilo de montaña y bosque tropical perennifolio. La ubicación de nuevos especímenes de V. planifolia en condiciones silvestres reduce un 66 % del área potencial de distribución, y la fragmenta, al pasar de ser una zona continua a convertirse en tres zonas geográficamente separadas. La reducción del hábitat se debió a un aumento en el número de plantas ubicadas, lo que define las condiciones ambientales a un nivel más exacto. Por lo anterior, se pueden emprender o diseñar acciones de conservación enfocadas a áreas más específicas dentro del estado de Oaxaca, México.
AbstractWild specimens of Vanilla planifolia represent a vital part of this resource primary gene pool, and some plants have only been reported in Oaxaca, Mexico. For this reason, we studied its geographical distribution within the state, to locate and describe the ecological characteristics of the areas where they have been found, in order to identify potential areas of establishment. The method comprised four stages: 1) the creation of a database with herbarium records, 2) the construction of the potential distribution based on historical herbarium records for the species, using the model of maximum entropy (MaxEnt) and 22 bioclimatic variables as predictors; 3) an in situ systematic search of individuals, based on herbarium records and areas of potential distribution in 24 municipalities, to determine the habitat current situation and distribution; 4) the description of the environmental factors of potential ecological niches generated by MaxEnt. A review of herbarium collections revealed a total of 18 records of V. planifolia between 1939 and 1998. The systematic search located 28 plants distributed in 12 sites in 95 364 Km2. The most important variables that determined the model of vanilla potential distribution were: precipitation in the rainy season (61.9 %), soil moisture regime (23.4 %) and precipitation during the four months of highest rainfall (8.1 %). The species potential habitat was found to be distributed in four zones: wet tropics of the Gulf of Mexico, humid temperate, humid tropical, and humid temperate in the Pacific. Precipitation oscillated within the annual ranges of 2 500 to 4 000 mm, with summer rains, and winter precipitation as 5 to 10 % of the total. The moisture regime and predominating climate were udic type I (330 to 365 days of moisture) and hot humid (Am/A(C) m). The plants were located at altitudes of 200 to 1 190 masl, on rough hillsides that generally make up the foothills of mountain systems, with altitudes of 1 300 to 2 500 masl. In natural conditions, distribution of the species is not limited to high evergreen forests, since it was also found in mountain mesophyll and tropical evergreen forests. The location of new specimens of V. planifolia in its wild condition reduces the potential distribution area by 66 %. This area is fragmented into three geographically separated areas. Habitat reduction was due to the increased number of located plants that define the environmental conditions into a more accurate level. Conservation actions can thus be designed and implemented, focusing on more specific areas within the state of Oaxaca, Mexico.