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2.
Exp Astron (Dordr) ; 57(1): 5, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39308933

RESUMEN

State-of-the-art 19th century spectroscopy led to the discovery of quantum mechanics, and 20th century spectroscopy led to the confirmation of quantum electrodynamics. State-of-the-art 21st century astrophysical spectrographs, especially ANDES at ESO's ELT, have another opportunity to play a key role in the search for, and characterization of, the new physics which is known to be out there, waiting to be discovered. We rely on detailed simulations and forecast techniques to discuss four important examples of this point: big bang nucleosynthesis, the evolution of the cosmic microwave background temperature, tests of the universality of physical laws, and a real-time model-independent mapping of the expansion history of the universe (also known as the redshift drift). The last two are among the flagship science drivers for the ELT. We also highlight what is required for the ESO community to be able to play a meaningful role in 2030s fundamental cosmology and show that, even if ANDES only provides null results, such 'minimum guaranteed science' will be in the form of constraints on key cosmological paradigms: these are independent from, and can be competitive with, those obtained from traditional cosmological probes.

3.
Aquat Toxicol ; 275: 107064, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39208620

RESUMEN

To date, the presence of pharmaceuticals has been extensively documented across a wide range of aquatic systems and biota. Further, substantial progress has been made in transitioning from laboratory assessments of pharmaceutical fate and effects in fish to in situ assessments of exposure and effects; however, certain research areas remain understudied. Among these is investigation of differential accumulation across multiple internal tissues in wild marine fish beyond the species commonly sampled in laboratory and freshwater field settings. This study examined the presence of pharmaceuticals across four tissues (plasma, muscle, brain, and liver) in a wild marine fish, bonefish (Albula vulpes), throughout coastal South Florida, USA. Differential accumulation across tissues was assessed for the number and concentration, identity, and composition of accumulated pharmaceuticals by sampling 25 bonefish and analyzing them for 91 pharmaceuticals. The concentration of pharmaceuticals was highest in plasma > liver > brain > muscle, while the number of pharmaceuticals was highest in liver > brain > plasma > muscle. The identity of detected pharmaceuticals was tissue specific, and there was an inverse relationship between the number of detections for each pharmaceutical and its log Kow. The composition of pharmaceuticals was tissue specific for both pharmaceutical presence/absence and concentration. Across all tissues, the greatest similarity was between brain and liver, which were more similar to plasma than to muscle, and muscle was the most distinct tissue. For tissue compositional variability, muscle was the most diverse in accumulated pharmaceuticals, while plasma, brain, and liver were similarly variable. With the highest concentrations in plasma and highest number in liver, and documented variability in accumulated pharmaceuticals across tissues, our results highlight the importance of tissue selection when surveying exposure in wild fish, suggesting that multi-tissue analysis would allow for a more comprehensive assessment of exposure diversity and risk of adverse effects.


Asunto(s)
Peces , Hígado , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/análisis , Distribución Tisular , Preparaciones Farmacéuticas/análisis , Preparaciones Farmacéuticas/metabolismo , Hígado/química , Hígado/metabolismo , Peces/metabolismo , Músculos/química , Músculos/metabolismo , Florida , Monitoreo del Ambiente , Encéfalo/metabolismo
5.
Pulmonology ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39112109

RESUMEN

Lung cancer (LC) is a leading cause of cancer-related mortality worldwide. Lung Cancer Screening (LCS) programs that use low-dose computed tomography (LDCT) have been shown to reduce LC mortality by up to 25 % and are considered cost-effective. The European Health Union has encouraged its Member States to explore the feasibility of LCS implementation in their respective countries. The task force conducted a comprehensive literature review and engaged in extensive discussions to provide recommendations. These recommendations encompass the essential components required to initiate pilot LCS programs following the guidelines established by the World Health Organization. They were tailored to align with the specific context of the Portuguese healthcare system. The document addresses critical aspects, including the eligible population, methods for issuing invitations, radiological prerequisites, procedures for reporting results, referral processes, diagnostic strategies, program implementation, and ongoing monitoring. Furthermore, the task force emphasized that pairing LCS with evidence-based smoking cessation should be the standard of care for a high-quality screening program. This document also identifies areas for further research. These recommendations aim to guarantee that the implementation of a Portuguese LCS program ensures high-quality standards, consistency, and uniformity across centres.

6.
J Hazard Mater ; 477: 135382, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39088947

RESUMEN

Pharmaceutical uptake involves processes that vary across aquatic systems and biota. However, single studies examining multiple environmental compartments, microhabitats, biota, and exposure pathways in mesoconsumer fish are sparse. We investigated the pharmaceutical burden in bonefish (Albula vulpes), pathways of exposure, and estimated exposure to a human daily dose. To evaluate exposure pathways, the number and composition of pharmaceuticals across compartments and the bioconcentration in prey and bonefish were assessed. To evaluate bioaccumulation, we proposed the use of a field-derived bioaccumulation factor (fBAF), due to variability inherent to natural systems. Exposure to a human daily dose was based on bonefish daily energetic requirements and consumption rates using pharmaceutical concentrations in prey. Pharmaceutical number and concentration were highest in prey, followed by bonefish, water and sediment. Fifteen pharmaceuticals were detected in common among bonefish, prey, and water; all of which bioconcentrated in prey and bonefish, and four bioaccumulated in bonefish. The composition of detected pharmaceuticals was compartment specific, and prey were most similar to bonefish. Bonefish were exposed to a maximum of 1.2 % of a human daily dose via prey consumption. Results highlight the need for multicompartment assessments of exposure and consideration of prey along with water as a pathway of exposure.


Asunto(s)
Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/farmacocinética , Preparaciones Farmacéuticas/metabolismo , Preparaciones Farmacéuticas/análisis , Peces/metabolismo , Bioacumulación , Cadena Alimentaria , Monitoreo del Ambiente , Humanos
7.
Braz J Biol ; 84: e278836, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38865565

RESUMEN

The increasing global importance of pink peppertree (Schinus terebinthifolia, Anacardiaceae) as a high-value commercial crop and its potential for expansion in production demand appropriate management due to uncertainties regarding its sexual system. This study focused on evaluating the morphology of sterile and fertile floral whorls, as well as analyzing the sexual system of pink pepper in two populations in northeastern Brazil. The results revealed no significant differences in the morphological characteristics of the flowers between the studied areas, suggesting that the species possesses notable adaptability to environmental conditions. However, a significant difference in the proportion of staminate individuals was observed in both areas, representing over 88% and 72%, respectively. A correlation was observed between the size of the stamens and the presence of apparently atrophied pistils (r=0.275; df=178; p<0.001), along with the occurrence of fruits in these hermaphroditic plants. In this context, the species should be considered gynodioecious due to the presence of plants with hermaphroditic flowers and plants with pistillate flowers. However, further research is essential to elucidate the role of pollinators, especially bees and wasps, and to better understand the fruiting process in hermaphroditic flowers. These insights have the potential to significantly enhance management aiming for efficient fruit production, promoting its economic and ecological relevance.


Asunto(s)
Anacardiaceae , Flores , Flores/anatomía & histología , Anacardiaceae/anatomía & histología , Anacardiaceae/clasificación , Brasil , Reproducción/fisiología , Polinización , Schinus
8.
Braz J Biol ; 84: e279769, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38922189

RESUMEN

Global biodiversity is under substantial threat due to biological invasions, a problem exacerbated by climate change. Such invasions have detrimental effects on the environment, economy, and human health, resulting in significant financial burdens. Recently, understanding these challenges has become a highlighted priority within the scientific community. This study focuses on the evaluation of Schinus terebinthifolia, native to South America, and its invasive spread into North and Central America, which has resulted in wide distribution and considerable impact. The primary objectives of this study include analyzing the potential distribution of the species under current and future climate scenarios, identifying the areas where its climatic niche is changing. Data collection encompassed a vast dataset of over 30,000 occurrence records of this species, from the following databases: (1) The Global Biodiversity Information Facility provided 22,163 records (GBIF), (2) The virtual Herbarium Reflora contributed 1,438 records, and NeoTropTree made available 6,591 records. Following a rigorous filtering process, 992 occurrences were considered for modeling. In this process, we utilized climate data and climate projections, employing various algorithms, with an emphasis on the consensus model methodology. The research results reveal a clear trend of reduced habitat suitability for S. terebinthifolia, especially under scenarios of high global warming. This accentuates the urgency of implementing emission control measures and mitigation strategies. Additionally, the study underscores the crucial importance of continuous monitoring, as well as actions for controlling and restoring affected ecosystems. The significant role played by S. terebinthifolia in both its native and invaded areas highlights the need for comprehensive management approaches. In the face of climate change and biodiversity threats, this study provides insightful observations on the dynamics of biological invasions. Success in addressing these issues relies on close cooperation between the scientific community, policymakers, land managers, and local communities. This collaboration is essential for guiding and conducting conservation and biodiversity management efforts in an ever-evolving world.


Asunto(s)
Anacardiaceae , Biodiversidad , Cambio Climático , Especies Introducidas , Brasil , Ecosistema , Modelos Biológicos , Schinus
9.
Animal ; 18(6): 101185, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38843664

RESUMEN

Although anticoccidials effectively control coccidiosis, a needed reduction in the reliance on antimicrobials in animal production leads to the exploration of alternative compounds. The present study aimed to test five different dietary treatments to counteract the negative impact of coccidiosis on broiler chickens' health and performance. 1-day-old male Ross 308 broilers (n = 960) were randomly assigned to one of eight treatments, with six cages per treatment (20 birds/cage). To the diet of the broiler chickens of treatments (Trt) 1-5, a synbiotic was added from d0-10. From d10-28, birds of Trt1 and Trt2 were fed synbiotics, whereas birds of Trt3 were fed diets with glutamine, and birds of Trt4 and Trt5 were fed diets with a combination of ß-glucans and betaine. From d28-35 onwards, birds of Trt1 were fed a diet with a synbiotic, whereas birds of Trt2-4 received diets with glutamine, and birds of Trt5 were fed a non-supplemented diet. Birds of the positive control group (PC; Trt6) were fed a standard diet supplemented with an anticoccidial (Decoquinate). The challenged negative control (NCchall; Trt7) and non-challenged negative control (NC) Trt8 were fed a standard diet without anticoccidial or other dietary treatment. At 7 days (d) of age, all birds were inoculated with 1 023, 115, and 512 sporulated oocysts of E. acervulina, E. maxima, and E. tenella, respectively, except for Trt8. Body weight gain (BWG), feed intake, and feed conversion ratio were assessed for each feeding phase (d0-10, d10-28 and d28-35) and overall experimental period (d0-35). Oocyst shedding, Eimeria lesion scores, cecal length, and relative weight were assessed at d13, d22, d28 and d35. Additionally, oocyst shedding was determined at d9 and d17. Litter quality was evaluated at d27 and d34, and footpad lesions at d34. During the starter (d0-10) and finisher (d28-35) periods, performance did not differ between the treatments. During the grower period (d10-28), Trt6 (PC) and Trt8 (NC) chickens had the highest BWG of all treatments (P < 0.001). Dietary treatment had no effect on litter quality and severity of footpad lesions. In the PC group (Trt6), low oocyst excretion and lesion scores were found. When comparing Trt1-5 with NCchall (Trt7), none of the treatments significantly reduced oocyst output or lesion scores. In conclusion, in this experiment, none of the dietary treatments performed similar or better compared to the PC group (Trt6) regarding performance or reducing Eimeria oocyst shedding or lesion scores.


Asunto(s)
Alimentación Animal , Pollos , Coccidiosis , Dieta , Eimeria , Oocistos , Enfermedades de las Aves de Corral , Animales , Coccidiosis/veterinaria , Enfermedades de las Aves de Corral/parasitología , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/tratamiento farmacológico , Masculino , Alimentación Animal/análisis , Eimeria/fisiología , Dieta/veterinaria , Suplementos Dietéticos/análisis , Simbióticos/administración & dosificación , Distribución Aleatoria , Betaína/administración & dosificación , Betaína/farmacología , Glutamina/farmacología , Glutamina/administración & dosificación , beta-Glucanos/farmacología , beta-Glucanos/administración & dosificación , beta-Glucanos/uso terapéutico
10.
Braz J Biol ; 84: e280128, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38836801

RESUMEN

This study evaluated the growth performance and parasite load of angelfish juveniles Pterophyllum scalare kept at different stocking densities using two rearing systems. The experiment was conducted in a factorial design (4x2) with four stocking densities (0.1, 0.4, 0.7, and 1.0 g/L), two type of aquarium tanks (glass and ceramic aquariums), and four replicates. The experiment lasted 60 days using 148 juvenile fish (3.05 ± 0.09 g) randomly placed in 32 aquariums (50 L) equipped with filters and aeration. All fish received two meals a day ad libitum (8:00 and 16:00). Water quality parameters such as temperature, dissolved oxygen, pH, and total ammonia were measured. At the end of the experiment, all fish were measured and weighed to determine growth performance and then subjected to parasitological analysis. The data were analyzed with a two-way ANOVA with post-hoc Tukey test (p<0.05). No effects on growth performance at different stocking densities were observed. However, there was an increase in Capillaria pterophylli infestation in the high stocking density within ceramic aquariums. Thus, this study recommends the use of 1.0 g/L for the intensive aquaculture system of freshwater angelfish, and applying cleaning management to avoid parasite infestation, particularly in ceramic aquariums.


Asunto(s)
Carga de Parásitos , Densidad de Población , Animales , Enfermedades de los Peces/parasitología , Acuicultura/métodos
12.
Rev. Soc. Cardiol. Estado São Paulo, Supl. ; 34(2B): 99-99, abr-jun. 2024. graf
Artículo en Portugués | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1561271

RESUMEN

INTRODUÇÃO: Dados de estudos randomizados avaliando os efeitos a longo prazo da cirurgia bariátrica no controle e remissão da hipertensão (HTN) são escassos. O seguimento de curto e médio prazo do Estudo GATEWAY (1 e 3 anos) mostrou melhora significativa e remissão da hipertensão após a cirurgia bariátrica. Aqui, apresentamos os dados de acompanhamento de 5 anos deste estudo. MÉTODOS: Conduzimos um ensaio clínico randomizado, em um centro único, fase III, paralelo e aberto. Pacientes com obesidade graus 1 e 2, tomando no mínimo 2 medicamentos anti-hipertensivos em doses máximas para hipertensão, foram alocados aleatoriamente para Bypass gástrico em Y de Roux (RYGB) combinado com tratamento clínico (TC) ou TC (estilo de vida/aconselhamento nutricional) isoladamente. O desfecho primário foi a redução de pelo menos 30% do total de anti-hipertensivos, mantendo níveis controlados de pressão arterial (PA)<140/90mmHg. A análise principal seguiu o princípio de intenção de tratar modificada e os valores ausentes foram imputados com a técnica de imputação múltipla. Os desfechos secundários incluíram vários biomarcadores. RESULTADOS: Foram incluídos 100 pacientes (76% mulheres, idade: 43,8±9,2 anos, índice de massa corporal, IMC: 36,9±2,7Kg/ m2). Após 5 anos, o IMC foi de 27,8±3,8kg/m2 para RYGB e 36,4±3,9kg/m2 para TC (P<0,001). 82,7% dos pacientes do grupo RYGB atingiram o desfecho primário, enquanto no grupo TC foram 14,7% (rate ratio 5,6 [95% CI]: 2,8 a 11,1; P<0,001) (Fig. A). A mediana (IQR) de número de drogas foi 1 (0-1) e 3 (3-4) para RYGB e TC, respectivamente. As taxas de remissão da hipertensão foram de 46,4 e 2% para RYGB e TC (Fig. B), respectivamente (P<0,001); A análise de sensibilidade considerando apenas os casos com seguimento concluído (n=69) revelou resultados consistentes. Os desfechos secundários nos grupos RYGB e TC, aos 60 meses, foram: circunferência abdominal 88,05 ± 9,84cm e 109,44 ± 9,76cm (P<0,001) ; hemoglobina glicada 5,4 ± 0,43% e 5,96 ± 0,9% (P<0,001) ; insulina 6,41 ± 2,46mU/L e 24,65 ± 16,57mU/L (P<0,001) ); LDL colesterol 93.61 ± 31.06mg/dL e 109.94 ± 37.58mg/dL (P=0,022); triglicerídeos 86,76 ± 38,45mg/dL e 140,33 ± 59,11 mg/dL (P<0,001); proteína C reativa de alta sensibilidade 0,81 ± 0,76mg/L e 6,13 ± 6,22mg/L (P=0,005), respectivamente. CONCLUSÕES: A cirurgia bariátrica é uma estratégia eficaz e duradoura no controle da PA com menor número ou nenhum medicamento anti-hipertensivo e na melhora do perfil metabólico e inflamatório em pacientes com obesidade graus 1 ou 2 e hipertensão.

13.
Radiography (Lond) ; 30(3): 715-722, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38428195

RESUMEN

INTRODUCTION: Ultrasound education varies greatly across European healthcare systems. This paper focuses on ultrasound academic education as a part of wider suite of surveys on radiographers working in ultrasound. The aim was to investigate sonography educational levels, methods of training, course duration and other factors in European Federation of Radiographers Societies (EFRS) member countries. METHOD: In 2019 an online survey was sent to the 38 EFRS member societies to distribute to higher education institutions within their own country. The survey was in English and contained different types of questions such as closed questions, free text options, and scale responses, to investigate sonography education including academic course types and duration, curriculum content, learning and teaching methods. RESULTS: A total of 45 responses were received, showing wide variation in the duration of training between the respective countries. Academic level 7 (part-time) ultrasound education was most frequently reported (n = 13), followed by direct entry ultrasound courses (n = 9) and bachelor's degree programmes at EQF level 6 (n = 7). The duration of part-time courses ranged from nine months up to four years. CONCLUSION: Sonography training and education varies among EFRS member countries ranging from short focused courses to postgraduate awards. Few countries offer sonography education leading to an award. The majority of clinical teaching and learning takes place in the learner's workplace. IMPLICATIONS FOR PRACTICE: High quality academic and clinical education for radiographers extending their role into ultrasound is important to ensure safe, effective sonography practice and good patient care.


Asunto(s)
Curriculum , Ultrasonografía , Europa (Continente) , Humanos , Encuestas y Cuestionarios , Sociedades Médicas , Competencia Clínica
14.
Pulmonology ; 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38309995

RESUMEN

INTRODUCTION AND OBJECTIVES: Hypersensitivity pneumonitis (HP) is an interstitial lung disease with diverse clinical features that can present a fibrotic phenotype similar to idiopathic pulmonary fibrosis (IPF) in genetically predisposed individuals. While several single nucleotide polymorphisms (SNPs) have been associated with IPF, the genetic factors contributing to fibrotic HP (fHP) remain poorly understood. This study investigated the association of MUC5B and TOLLIP variants with susceptibility, clinical presentation and survival in Portuguese patients with fHP. MATERIAL AND METHODS: A case-control study was undertaken with 97 fHP patients and 112 controls. Six SNPs residing in the MUC5B and TOLLIP genes and their haplotypes were analyzed. Associations with risk, survival, and clinical, radiographic, and pathological features of fHP were probed through comparisons among patients and controls. RESULTS: MUC5B rs35705950 and three neighboring TOLLIP variants (rs3750920, rs111521887, and rs5743894) were associated with increased susceptibility to fHP. Minor allele frequencies were greater among fHP patients than in controls (40.7% vs 12.1%, P<0.0001; 52.6% vs 40.2%, P = 0.011; 22.7% vs 13.4%, P = 0.013; and 23.2% vs 12.9%, P = 0.006, respectively). Haplotypes formed by these variants were also linked to fHP susceptibility. Moreover, carriers of a specific haplotype (G-T-G-C) had a significant decrease in survival (adjusted hazard ratio 6.92, 95% CI 1.73-27.64, P = 0.006). Additional associations were found between TOLLIP rs111521887 and rs5743894 variants and decreased lung function at baseline, and the MUC5B SNP and radiographic features, further highlighting the influence of genetic factors in fHP. CONCLUSION: These findings suggest that TOLLIP and MUC5B variants and haplotypes may serve as valuable tools for risk assessment and prognosis in fibrotic hypersensitivity pneumonitis, potentially contributing to its patient stratification, and offer insights into the genetic factors influencing the clinical course of the condition.

15.
Braz J Biol ; 84: e278601, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422291

RESUMEN

The use of biomass for energy production constitutes a promising strategy that warrants the search for new sources of biomass. Elephant grass has been gaining notoriety due to its high dry matter yield and rapid growth. The present study was carried out to quantify the genetic divergence of nine elephant grass half-sib families in order to identify genotypes with greater genetic divergence and productive potential for hybridization, using the hierarchical clustering methodology based on principal components. Half-sib families were generated using genotypes from the Active Germplasm Bank of Elephant Grass. The experiment was laid out in a randomized-block design with nine half-sib families, three replicates, and eight plants per plot. A total of 216 genotypes of elephant grass were evaluated. Principal component (PC), biplot, and hierarchical clustering analyses for diversity estimation were conducted using R software. The first two PCs of biplot analysis accounted for 64% of the cumulative variation. Dry matter yield was the most important trait for genotype discrimination (0.89), followed by plant height (0.67) and stem diameter (0.61) in PC1. In this analysis, the distances between accessions were considered and there were no family links, which indicates the existence of wide variability within the evaluated families, since genotypes belonging to the same family were not grouped together, but rather distributed into different groups. Crosses between genotypes of group three and genotypes of groups one and two are recommended for the development of high-yielding genotypes when aiming at energy production.


Asunto(s)
Variación Genética , Hibridación Genética , Biomasa , Variación Genética/genética , Genotipo , Fenotipo , Distribución Aleatoria
16.
Radiography (Lond) ; 30(2): 483-491, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38219390

RESUMEN

INTRODUCTION: Research has been performed by sonographers (also known as ultrasound reporting radiographers) for many years for improving diagnosis of disease, developing new imaging approaches, and enhancing patient outcomes. Despite this, sonographers' perspectives on research have not been well studied. To understand the views of sonographers is essential, as they have an important role in the successful implementation of research outcomes during their daily work. The study aimed to explore sonographers' perspectives on research. METHODS: This cross-sectional online questionnaire was developed, and pilot tested, before distribution on social media platforms by the research group to sonographers or reporting radiographers in ultrasound worldwide. The questionnaire included 21-items. The link was open for 8 weeks in the spring of 2023. A mix of closed, open and scale questions were used. Informed consent was mandatory, and information about the study and anonymity was presented. RESULTS: A total of 165 sonographers participated in the questionnaire of which 66.1 % were from Europe (n = 109), 6.1 % from North America (n = 10), 0.6 % from South America (n = 1), 2.4 % from Asia (n = 4), 13.3 % from Africa (n = 22) and 11.5 % from Oceania (n = 19). A total of 32 % of the participants had performed research. Also, 68.5 % would like to become more involved in research. CONCLUSION: Most sonographers work in large hospitals, and half of them have obtained academic level 7 education. A limited number of sonographers have published peer reviewed papers. Many sonographers expressed an interest in research. This suggests a potential for future development of the sonographers' role in research. IMPLICATIONS FOR PRACTICE: The findings for this study provide insight that could be used to improve research practice for sonographers.


Asunto(s)
Técnicos Medios en Salud , Humanos , Estudios Transversales , Ultrasonografía , Encuestas y Cuestionarios , Europa (Continente)
17.
Eur J Prosthodont Restor Dent ; 32(1): 102-108, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-37812514

RESUMEN

AIM: Evaluate the influence of occlusal loading on the stress distribution of endodontically treated teeth after root canal preparation with different file's sizes and tapers by means of finite element analysis. METHODOLOGY: Seven three-dimensional models of a single-rooted, single-canal lower second premolar were established, one healthy control and six endodontically treated and restored models. The shape of root canal preparations followed file configurations 30/.05, 30/.09, 35/.04, 35/.06, 40/.04, and 40/.06. Von- Mises equivalent stresses were calculated by applying 30 N, 90 N and 270 N loads to the buccal cusp tip, each one at 90º, 45º and 20º angles from the occlusal plane simulating occlusion, dental interference and laterality, respectively. RESULTS: 45º loading was more prone to formation of higher stress values. The simulation of occlusion and laterality resulted in maximum stress areas located at the inner side of the root curvature, while under occlusal interference they were on the lingual surface over the tooth's long axis. CONCLUSIONS: The angulation of occlusal loading and magnitude were determinants for stress distribution on dental structure. Both variations of size and taper were not determinants for the increase in the maximum stress areas.


Asunto(s)
Diente no Vital , Humanos , Diente no Vital/terapia , Análisis de Elementos Finitos , Oclusión Dental , Simulación por Computador , Preparación del Conducto Radicular , Análisis del Estrés Dental/métodos , Estrés Mecánico
18.
Chemosphere ; 349: 140949, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38096990

RESUMEN

Most research on pharmaceutical presence in the environment to date has focused on smaller scale assessments of freshwater and riverine systems, relying mainly on assays of water samples, while studies in marine ecosystems and of exposed biota are sparse. This study investigated the pharmaceutical burden in bonefish (Albula vulpes), an important recreational and artisanal fishery, to quantify pharmaceutical exposure throughout the Caribbean Basin. We sampled 74 bonefish from five regions, and analyzed them for 102 pharmaceuticals. We assessed the influence of sampling region on the number of pharmaceuticals, pharmaceutical assemblage, and risk of pharmacological effects. To evaluate the risk of pharmacological effects at the scale of the individual, we proposed a metric based on the human therapeutic plasma concentration (HTPC), comparing measured concentrations to a threshold of 1/3 the HTPC for each pharmaceutical. Every bonefish had at least one pharmaceutical, with an average of 4.9 and a maximum of 16 pharmaceuticals in one individual. At least one pharmaceutical was detected in exceedance of the 1/3 HTPC threshold in 39% of bonefish, with an average of 0.6 and a maximum of 11 pharmaceuticals exceeding in a Key West individual. The number of pharmaceuticals (49 detected in total) differed across regions, but the risk of pharmacological effects did not (23 pharmaceuticals exceeded the 1/3 HTPC threshold). The most common pharmaceuticals were venlafaxine (43 bonefish), atenolol (36), naloxone (27), codeine (27), and trimethoprim (24). Findings suggest that pharmaceutical detections and concentration may be independent, emphasizing the need to monitor risk to biota regardless of exposure diversity, and to focus on risk quantified at the individual level. This study supports the widespread presence of pharmaceuticals in marine systems and shows the utility of applying the HTPC to assess the potential for pharmacological effects, and thus quantify impact of exposure at large spatial scales.


Asunto(s)
Ecosistema , Contaminantes Químicos del Agua , Humanos , Animales , Peces , Región del Caribe , Biota , Preparaciones Farmacéuticas , Contaminantes Químicos del Agua/toxicidad , Monitoreo del Ambiente
19.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469306

RESUMEN

Abstract Petroleum water soluble fraction (WSF) impairs organisms, but damages may vary among cell and tissue levels. The aim of the present study was to evaluate the acute (24 h, 48 h, 72 h) and subchronic effects (36 days) of WSF (0%, 25% and 100%) in juveniles of the Neotropical top predator fish Hoplias aff. malabaricus. The effects of WSF were evaluated at a molecular level using the comet assay and micronucleus test for genome damage; and at a morphological level through histological identification of liver pathologic lesions. In both acute and subchronic exposure we found low levels of DNA damage ( 10% of comet tail) and non-significant frequency of micronucleus in WSF exposed fish. The most significant liver lesions in WSF exposed fish were fatty vacuolization, hypertrophy and focal necrosis. Since these tissue injuries were progressive and persistent, their irreversibility may negatively affect fish recruitment, even in a such resistant top predator.


Resumo A fração solúvel de petróleo (WSF) prejudica os organismos, porém os danos podem variar entre os níveis celular e tecidual. O objetivo do presente estudo foi avaliar o efeito agudo (24 h, 48 h e 72 h) e subcrônico (36 dias) da WSF (0%, 25% e 100%) em juvenis do peixe neotropical predador topo Hoplias aff. malabaricus. Os efeitos da WSF foram avaliados no nível molecular utilizando o ensaio do cometa e o teste do micronúcleo para o dano genômico e no nível morfológico através da identificação histológica de lesões patológicas no fígado. Em ambas exposições (aguda e subcrônica) encontramos baixos níveis de dano no DNA ( 10% de DNA na cauda do cometa) e frequência de micronúcleos não significativa em peixes expostos a WSF. As lesões mais significativas no fígado dos peixes expostos a WSF foram a vacuolização lipídica, hipertrofia e focos de necroses. Como estas lesões foram progressivas e persistentes, sua irreversibilidade pode afetar negativamente o recrutamento dos peixes, mesmo sendo um predador topo resistente.

20.
Braz. j. biol ; 84: e253731, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355871

RESUMEN

Abstract Petroleum water soluble fraction (WSF) impairs organisms, but damages may vary among cell and tissue levels. The aim of the present study was to evaluate the acute (24 h, 48 h, 72 h) and subchronic effects (36 days) of WSF (0%, 25% and 100%) in juveniles of the Neotropical top predator fish Hoplias aff. malabaricus. The effects of WSF were evaluated at a molecular level using the comet assay and micronucleus test for genome damage; and at a morphological level through histological identification of liver pathologic lesions. In both acute and subchronic exposure we found low levels of DNA damage (< 10% of comet tail) and non-significant frequency of micronucleus in WSF exposed fish. The most significant liver lesions in WSF exposed fish were fatty vacuolization, hypertrophy and focal necrosis. Since these tissue injuries were progressive and persistent, their irreversibility may negatively affect fish recruitment, even in a such resistant top predator.


Resumo A fração solúvel de petróleo (WSF) prejudica os organismos, porém os danos podem variar entre os níveis celular e tecidual. O objetivo do presente estudo foi avaliar o efeito agudo (24 h, 48 h e 72 h) e subcrônico (36 dias) da WSF (0%, 25% e 100%) em juvenis do peixe neotropical predador topo Hoplias aff. malabaricus. Os efeitos da WSF foram avaliados no nível molecular utilizando o ensaio do cometa e o teste do micronúcleo para o dano genômico e no nível morfológico através da identificação histológica de lesões patológicas no fígado. Em ambas exposições (aguda e subcrônica) encontramos baixos níveis de dano no DNA (< 10% de DNA na cauda do cometa) e frequência de micronúcleos não significativa em peixes expostos a WSF. As lesões mais significativas no fígado dos peixes expostos a WSF foram a vacuolização lipídica, hipertrofia e focos de necroses. Como estas lesões foram progressivas e persistentes, sua irreversibilidade pode afetar negativamente o recrutamento dos peixes, mesmo sendo um predador topo resistente.


Asunto(s)
Animales , Contaminantes Químicos del Agua/toxicidad , Petróleo/toxicidad , Characiformes , Agua Dulce , Hígado
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