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The experimental study and transplantation of pancreatic islets requires their isolation from the surrounding tissue, and therefore, from the vasculature. Under these conditions, avascular islets rely on the diffusion of peripheral oxygen and nutrients to comply with the requirements of islet cells while responding to changes in body glucose. As a complement to the experimental work, computational models have been widely used to estimate how avascular islets would be affected by the hypoxic conditions found both in culture and transplant sites. However, previous models have been based on simplified representations of pancreatic islets which has limited the reach of the simulations performed. Aiming to contribute with a more realistic model of avascular human islets, in this work we used architectures of human islets reconstructed from experimental data to simulate the availability of oxygen for α, ß and δ-cells, emulating culture and transplant conditions at different glucose concentrations. The modeling approach proposed allowed us to quantitatively estimate how the loss of cells due to severe hypoxia would impact interactions between islet cells, ultimately segregating the islet into disconnected subnetworks. According to the simulations performed, islet encapsulation, by reducing the oxygen available within the islets, could severely compromise cell viability. Moreover, our model suggests that even without encapsulation, only microislets composed of less than 100 cells would remain viable in oxygenation conditions found in transplant sites. Overall, in this article we delineate a novel modeling methodology to simulate detailed avascular islets in experimental and transplant conditions with potential applications in the field of islet encapsulation.
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Sobrevivência Celular , Simulação por Computador , Glucose , Ilhotas Pancreáticas , Modelos Biológicos , Oxigênio , Humanos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/irrigação sanguínea , Oxigênio/metabolismo , Glucose/metabolismo , Sobrevivência Celular/fisiologia , Biologia Computacional , Transplante das Ilhotas Pancreáticas/métodos , Hipóxia Celular/fisiologiaRESUMO
Climate change is causing serious damage to natural and social systems, as well as having an impact on human health. Among the direct effects of climate change is the rise in global surface temperatures and the increase in the frequency, duration, intensity and severity of heat waves. In addition, understanding of the adaptation process of the exposed population remains limited, posing a challenge in accurately estimating heat-related morbidity and mortality. In this context, this study seeks to establish a conceptual framework that would make it easier to understand and organise knowledge about human adaptation to heat and the factors that may influence this process. An inductive approach based on grounded theory was used, through the analysis of case studies connecting concepts. The proposed conceptual framework is made up of five components (climate change, vulnerability, health risks of heat, axes of inequality and health outcomes), three heat-adaptation domains (physiological, cultural and political), two levels (individual and social), and the pre-existing before a heat event. The application of this conceptual framework facilitates the assistance of decision-makers in planning and implementing effective adaptation measures. Recognizing the importance of addressing heat adaptation as a health problem that calls for political solutions and social changes. Accordingly, this requires a multidisciplinary approach that would foster the participation and collaboration of multiple actors for the purpose of proposing effective measures to address the health impact of the rise in temperature.
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Mudança Climática , Temperatura Alta , Humanos , Temperatura Alta/efeitos adversos , Adaptação FisiológicaRESUMO
INTRODUCTION: Vibrato is an oscillation in frequency, intensity, and timbre of the singing voice. Previous studies have found a relationship between its periodicity and perceived quality. The diversity of vibrato enriches the music and singer's performances but create challenges for quantifying and capturing the characteristics that contribute to achieving these expressive goals. Vibrato tones have been addressed using rate, extent, jitter, and shimmer; however, these do not necessarily capture relevant complex time-varying features. This paper applies techniques from disciplines that specialize in periodicity and complexity to provide insight into vibrato characteristics not yet understood. OBJECTIVES: This study aimed to assess whether nonlinear metrics are relevant features in characterizing and illustrating differences in vibrato behavior in opera and jazz singing, as well as considering the relationship of nonlinear metrics to other vibrato parameters. METHODS: Vibrato tones from published music material of world-class singers from opera and jazz were analyzed with entropy, recurrence, and the established parameters of rate, extent, jitter, and shimmer. Dimensionality reduction was employed to consider the relationship and significance of each of the metrics in collectively characterizing vibrato. RESULTS: The principal component, explaining 40% of variability, had positive weights of determinism and line length derived from recurrence while having negative weights of rate, shimmer, and sample entropy. Using these components, the vibrato tones from opera compared to jazz singing were found to be more regular and had lower rate and extent, and it was possible to spotlight singers and notes with high periodicity. CONCLUSION: Our study shows that nonlinear metrics applied to vibrato tones provide a valuable tool for observing and quantifying regularity in vibrato tones. The results of this study highlight the potential for more detailed descriptions of vibrato characteristics that may support categorization of individuals, genres, or musical expression in the future and could be applicable to pedagogical techniques.
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Goat milk composition is affected by feeding, and in semiarid rangeland, information on Creole goat milk physicochemical composition is lacking. For the fulfillment of this objective, three agroecological regions (AR) considering altitude (lowland 87, highland 779, and mountain 1309 m above sea level) with different botanical compositions were chosen. Every AR analyzed accounted for 30 goat herds, with a total of 90 herds. The results demonstrated that altitude had an influence mainly on density and protein. Milk density increases as altitude increases; conversely, milk protein increases as altitude decreases. On the other hand, in the mountain and lowland ARs, the salts and solids not fat (SNF) percentages were higher compared to that of the highland AR (p < 0.05). The freezing point (FP) was higher at highland altitudes compared to that of mountain and lowland ARs (p < 0.01). In the milk fatty acids (FA) profile, only the C14:1 value was affected by altitude, whereas goat milk at lowland and mountain altitudes had higher values compared to that at highland altitudes (p < 0.05). Additionally, late lactation stage fat, FP, and pH values were higher compared to early lactation values. The opposite effect was observed for salts and SNF. In the FA profile, late lactation values were higher for C10:0 and C8:0 compared to early lactation values. The opposite trend was observed for C18:2n6t. The thrombogenic index was significantly higher at lowland altitudes compared to highland altitudes, and similar to the mountain AR. These goat milk characteristics could be explained as a consequence of animal nutrition, as well as the goat's meat-type phenotype.
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Introduction: Telogen effluvium is a form of non-scarring alopecia characterized by an increased hair shedding rate induced by mechanical or inflammatory factors. Case Report: A 27-year-old healthy male patient presented with several itchy alopecic patches in the occipital region. The patient had undergone a follicular unit extraction 6 weeks before with complete recovery after 1 week. Upon trichoscopy, we found empty follicular openings, short regrowing hairs, and coudability hairs. A diagnosis of acute telogen effluvium was made, and the patient was started on betamethasone lotion for daily use as a means to treat pruritus. After 1 month, the patient presented an almost complete response. Conclusion: While acute telogen effluvium is commonly seen in the receptor area after a hair transplant, the incidence of the donor region as a presentation is unknown. Common trichoscopic findings in telogen effluvium include empty follicular openings, short regrowing hairs, and lack of other signs usually seen in other types of alopecia. This description was consistent with what we found in our patient. Trichoscopic findings can help in the diagnosis, and understanding its natural course, physicians can reassure the patient about the self-resolutive outcome of this condition.
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Pancreatic islets are mini-organs composed of hundreds or thousands of É, ß and δ-cells, which, respectively, secrete glucagon, insulin and somatostatin, key hormones for the regulation of blood glucose. In pancreatic islets, hormone secretion is tightly regulated by both internal and external mechanisms, including electrical communication and paracrine signaling between islet cells. Given its complexity, the experimental study of pancreatic islets has been complemented with computational modeling as a tool to gain a better understanding about how all the mechanisms involved at different levels of organization interact. In this review, we describe how multicellular models of pancreatic cells have evolved from the early models of electrically coupled ß-cells to models in which experimentally derived architectures and both electrical and paracrine signals have been considered.
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Células Secretoras de Insulina , Ilhotas Pancreáticas , Ilhotas Pancreáticas/fisiologia , Células Secretoras de Insulina/fisiologia , Insulina , Glucagon , Hormônios PancreáticosRESUMO
Eosinophilic esophagitis is a chronic inflammatory disease characterized by esophageal dysfunction and progression to fibrosis. Its incidence is increasing in our setting with deep regional variations. To corroborate this hypothesis, a longitudinal, retrospective, multicenter observational study was carried out of patients who received a diagnosis of eosinophilic esophagitis from 2008 to 2022 at public hospitals in the province of Zaragoza. The annual incidence rates and mean incidence rate were calculated using the data for the reference population. A total of 104 patients were included. The mean incidence rate was 5.1 cases per 100,000 inhabitants < 15 years old/year (0.75-11.2). In the first five-year period (2008-2012) the rate was 1.2 cases per 100,000 inhabitants/year, compared with a rate of 6 cases per 100,000 inhabitants/year in the second 5-year period (2013-2017), [OR 5,68 (IC 95% 2,55 - 12,67, p < 0,05]; and 8.1 cases per 100,000 inhabitants/year in the third five-year period (2018-2022), [OR 7,74 (IC 95% 3,52 - 16,99, p < 0,05] It is concluded that eosinophilic esophagitis incidence has increased among the child population of Zaragoza over the past 15 years, with a 7-fold higher risk of having the condition in the third five-year period compared with the first one.
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The calyxes of Hibiscus sabdariffa present multiple pharmacological effects primarily attributed to their high anthocyanin content; however, little is known about their phytoestrogenic effect. Ovarian hypofunction (OH) is a process characterized by the rapid detention of the production of ovarian hormones, which compromises reproductive and cognitive functions. Hormone replacement therapy (HRT) efficiently compensates for OH; nevertheless, questions have been raised on its secondary effects and safety. One of the alternatives to tackling OH involves using phytoestrogens such as anthocyanins for their structural similarity to natural estrogens. In a Wistar rat model of ovariectomy (OVX), we recently reported the beneficial properties of an anthocyanin-rich extract prepared from the calyces of H. sabdariffa (HSE) in hindering the adverse effects of OH on memory performance and highlighted a possible phytoestrogenic impact through the modulation of estrogen receptor (ER) expression. We now report that HSE and estradiol differentially affected the expression of ERα and ERß. ERα was more sensitive to HSE; meanwhile, estradiol preferentially modulated ERß. Thus, our study leads to further research on using H. sabdariffa as a nutrition-based alternative to HRT.
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Hibiscus , Fitoestrógenos , Ratos , Animais , Feminino , Fitoestrógenos/farmacologia , Ratos Wistar , Receptor alfa de Estrogênio/metabolismo , Antocianinas/farmacologia , Hibiscus/química , Receptor beta de Estrogênio/metabolismo , Estradiol/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/químicaRESUMO
Climate change is currently regarded as the greatest global threat to human health, and its health-related consequences take different forms according to age, sex, socioeconomic level, and type of territory. The aim of this study is to ascertain the differences in vulnerability and the heat-adaptation process through the minimum mortality temperature (MMT) among the Spanish population aged ≥65 years by territorial classification. A retrospective, longitudinal, ecological time-series study, using provincial data on daily mortality and maximum daily temperature across the period 1983-2018, was performed, differentiating between urban and nonurban populations. The MMTs in the study period were higher for the ≥65-year age group in urban provinces, with a mean value of 29.6 °C (95%CI 29.2-30.0) versus 28.1 °C (95%CI 27.7-28.5) in nonurban provinces. This difference was statistically significant (p < 0.05). In terms of adaptation levels, higher average values were obtained for nonurban areas, with values of 0.12 (95%CI -0.13-0.37), than for urban areas, with values of 0.09 (95%CI -0.27-0.45), though this difference was not statistically significant (p < 0.05). These findings may contribute to better planning by making it possible to implement more specific public health prevention plans. Lastly, they highlight the need to conduct studies on heat-adaptation processes, taking into account various differential factors, such as age and territory.
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Aclimatação , Temperatura Alta , Humanos , Idoso , Espanha/epidemiologia , Estudos Retrospectivos , Adaptação Fisiológica , MortalidadeRESUMO
The capacity for adaptation to climate change is limited, and the elderly rank high among the most exposed population groups. To date, few studies have addressed the issue of heat adaptation, and little is known about the long-term effects of exposure to heat. One indicator that allows the ascertainment of a population's level of adaptation to heat is the minimum mortality temperature (MMT), which links temperature and daily mortality. The aim of this study was to ascertain, firstly, adaptation to heat among persons aged ≥ 65 years across the period 1983 to 2018 through analysis of the MMT; and secondly, the trend in such adaptation to heat over time with respect to the total population. A retrospective longitudinal ecological time series study was conducted, using data on daily mortality and maximum daily temperature across the study period. Over time, the MMT was highest among elderly people, with a value of 28.6 °C (95%CI 28.3-28.9) versus 28.2 °C (95%CI 27.83-28.51) for the total population, though this difference was not statistically significant. A total of 62% of Spanish provinces included populations of elderly people that had adapted to heat during the study period. In general, elderly persons' level of adaptation registered an average value of 0.11 (°C/decade).
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Termotolerância , Idoso , Humanos , Espanha/epidemiologia , Estudos Retrospectivos , Temperatura , Temperatura Alta , MortalidadeRESUMO
INTRODUCTION: Arguably one of the most controversial features of the singing voice, especially in a choral context, is the phenomenon of vibrato. Numerous pedagogical articles, mostly written by experienced choral singers or directors, discuss the importance of vibrato, sharing anecdotal insights about its control (often advocating reduction) in choral blend and vocal health. OBJECTIVES: This systematic review aims to identify the main questions posed in the empirical study of vibrato during group singing, and how they have been addressed to date through empirical investigations. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses was employed for this review. The review team consisted of the two authors. A data extraction form was designed to capture information about the participants (including age, gender, music and singing experience), study methods, experimental procedures, outcome measures, and statistical findings. RESULTS: Seventeen studies were included in the review and revealed that (a) relatively few empirical investigations have studied vibrato in vocal ensembles; (b) the majority focused on vibrato production rather than perception; (c) methodological approaches include Synthesis, Multi-track recordings, Stereo/Binaural recordings, and Lx/Contact recordings; and (d) the studies focused on the main themes of Adjustment, Identification, Interaction, Intonation, and Style. CONCLUSION: With the current body of literature, it is not possible to draw general conclusions around vibrato behavior during group singing. However, the review highlights the main subareas of interest and valuable methods which have been established and through which future research can collectively shed further light on the role of vibrato in choral singing.
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An updated checklist of tongue worms (Pentastomida) which parasitize wild North American amphibians and reptiles is presented: a total of 14 species grouped in 6 genera, 4 families, and 2 orders are registered; these infect a total of 58 species of reptiles and 3 amphibians in the region. An illustrated identification key for the taxa listed is proposed. Kiricephalus coarctatus (Diesing, 1860) (Porocephalidae) is recorded for the first time in the snakes Arizona elegans Kennicott, 1859 (Colubridae); Micrurus tener Baird and Girard, 1853 (Elapidae); and Bothrops asper (Garman, 1884) (Viperidae); the exotic Raillietiella taegueselfiRiley, McAllister, and Freed, 1988 (Raillietiellidae) is recorded in the exotic lizard Hemidactylus frenatus Duméril and Bibron, 1836 (Gekkonidae) for the first time, and in Hemidactylus turcicus (Linnaeus, 1758) (Gekkonidae) for the first time in Mexico, this is also the first time it is recorded in a species of lizard native of the Americas, Sceloporus cyanogenys Cope, 1885 (Phrynosomatidae), this latter record represents a parasite spillover event; finally, Porocephalus stilesiSambon, 1910 (Porocephalidae) is formally recorded for the first time in Mexico in the snake Bothrops asper.
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Colubridae , Lagartos , Parasitos , Pentastomídeos , Animais , México , Lista de Checagem , Lagartos/parasitologiaRESUMO
Adverse health effects from extreme heat remain a major risk, especially in a changing climate. Several European countries have implemented heat health action plans (HHAPs) to prevent ill health and excess mortality from heat. This paper assesses the state of implementation of HHAPs in the WHO European Region and discusses barriers and successes since the early 2000s. The results are based on a web-based survey among 53 member states on the current national and federal HHAPs in place. Guided by the eight core elements of HHAPs as outlined by the WHO Regional Office for Europe guidance from 2008, we analyzed which elements were fully or partially implemented and which areas of improvement countries identified. HHAP adaptations to account for COVID-19 were sought via literature search and expert consultations. 27 member states provided information, of which 17 countries reported having a HHAP. Five out of eight core elements, namely agreement on a lead body, accurate and timely alert systems, heat-related health information plans, strategies to reduce health exposure, and care for vulnerable groups, were at least partially implemented in all 17 plans. Alert systems were implemented most often at 94%. The least often implemented items were real-time surveillance, long-term urban planning, and preparedness of health and social systems. Five countries had published COVID-19 guidance online. Our findings suggest a progressive improvement in the development and rollout of HHAPs overall and awareness of vulnerable population groups in WHO/Europe, while integration of HHAPs into long-term climate change and health planning remains a challenge.
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COVID-19 , Planejamento em Saúde , Temperatura Alta , Humanos , Políticas , Estados Unidos , Organização Mundial da SaúdeRESUMO
INTRODUCTION: There are various scales designed to determine the risk of malnutrition at hospital admission in children. However, most of these instruments are developed and published in English. Their cross-cultural adaptation and validation being mandatory in order to be used in our country. OBJECTIVES: Cross-culturally adapt three scales designed to determine the risk of malnutrition linked to the disease and determine the validity of their content. MATERIAL AND METHODS: Cross-cultural adaptation using the translation-back-translation method in accordance with the recommendations of the International Test Commission Guidelines for Translating and Adapting Tests. Content validity was measured by a panel of experts (under seven basic selection criteria adapted from the Fehring model) who evaluated each item of the scales by measuring 4 criteria: ambiguity, simplicity, clarity and relevance. With the extracted score, Aiken's V statistic was obtained for each item and for the complete scales. RESULTS: Starting from three independent translations per scale, 3 definitive versions in Spanish of the PNRS, STRONGkids and STAMP scales were obtained semantically equivalent to their original versions. The PNRS and STRONGkids scales presented an Aiken's V greater than 0.75 in all their items, while the STAMP scale presented a value less than 0.75 for the item "weight and height". CONCLUSION: This study provides the transculturally adapted Spanish versions of the PNRS, STRONGkids and STAMP scales. The PNRS and STRONGkids scales present valid content to be applied in the state hospital context. STAMP requires the adaptation of its item "weight and height" to consider its use in a Spanish child population adequate.
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Comparação Transcultural , Desnutrição , Criança , Humanos , TraduçõesRESUMO
Background: The objective of this study was to identify which air pollutants, atmospheric variables and health determinants could influence COVID-19 mortality in Spain. This study used information from 41 of the 52 provinces in Spain (from Feb. 1, to May 31, 2021). Generalized Linear Models (GLM) with Poisson link were carried out for the provinces, using the Rate of Mortality due to COVID-19 (CM) per 1,000,000 inhabitants as dependent variables, and average daily concentrations of PM10 and NO2 as independent variables. Meteorological variables included maximum daily temperature (Tmax) and average daily absolute humidity (HA). The GLM model controlled for trend, seasonalities and the autoregressive character of the series. Days with lags were established. The relative risk (RR) was calculated by increases of 10 g/m3 in PM10 and NO2 and by 1 â in the case of Tmax and 1 g/m3 in the case of HA. Later, a linear regression was carried out that included the social determinants of health. Results: Statistically significant associations were found between PM10, NO2 and the CM. These associations had a positive value. In the case of temperature and humidity, the associations had a negative value. PM10 being the variable that showed greater association, with the CM followed of NO2 in the majority of provinces. Anyone of the health determinants considered, could explain the differential geographic behavior. Conclusions: The role of PM10 is worth highlighting, as the chemical air pollutant for which there was a greater number of provinces in which it was associated with CM. The role of the meteorological variables-temperature and HA-was much less compared to that of the air pollutants. None of the social determinants we proposed could explain the heterogeneous geographical distribution identified in this study. Supplementary Information: The online version contains supplementary material available at 10.1186/s12302-022-00617-z.
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This study aims to identify the combined role of environmental pollutants and atmospheric variables at short term on the rate of incidence (TIC) and on the hospital admission rate (TIHC) due to COVID-19 disease in Spain. This study used information from 41 of the 52 provinces of Spain (from Feb. 1, 2021 to May 31, 2021). Using TIC and TIHC as dependent variables, and average daily concentrations of PM10 and NO2 as independent variables. Meteorological variables included maximum daily temperature (Tmax) and average daily absolute humidity (HA). Generalized linear models (GLM) with Poisson link were carried out for each provinces The GLM model controlled for trend, seasonalities, and the autoregressive character of the series. Days with lags were established. The relative risk (RR) was calculated by increases of 10 µg/m3 in PM10 and NO2 and by 1 °C in the case of Tmax and 1 g/m3 in the case of HA. Later, a linear regression was carried out that included the social determinants of health. Statistically significant associations were found between PM10, NO2, and the rate of COVID-19 incidence. NO2 was the variable that showed greater association, both for TIC as well as for TIHC in the majority of provinces. Temperature and HA do not seem to have played an important role. The geographic distribution of RR in the studied provinces was very much heterogeneous. Some of the health determinants considered, including income per capita, presence of airports, average number of diesel cars per inhabitant, average number of nursing personnel, and homes under 30 m2 could explain the differential geographic behavior. As findings indicates, environmental factors only could modulate the incidence and severity of COVID-19. Moreover, the social determinants and public health measures could explain some patterns of geographically distribution founded.
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Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , COVID-19/epidemiologia , Humanos , Dióxido de Nitrogênio , Material Particulado/análise , Espanha/epidemiologiaRESUMO
Structural properties of pancreatic islets are key for the functional response of insulin, glucagon, and somatostatin-secreting cells, due to their implications in intraislet communication via electric, paracrine, and autocrine signaling. In this protocol, the three-dimensional architecture of a pancreatic islet is firstly reconstructed from experimental data using a novel computational algorithm. Next, the morphological and connectivity properties of the reconstructed islet, such as the number and percentages of the different type of cells, cellular volume, and cell-to-cell contacts, are obtained. Then, network theory is used to describe the connectivity properties of the islet through network-derived metrics such as average degree, clustering coefficient, density, diameter, and efficiency. Finally, all these properties are functionally evaluated through computational simulations using a model of coupled oscillators. Overall, here we describe a step-by-step workflow, implemented in IsletLab, a multiplatform application developed specifically for the study and simulation of pancreatic islets, to apply a novel computational methodology to characterize and analyze pancreatic islets as a complement to the experimental work.