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1.
J Hazard Mater ; 472: 134473, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38703681

RESUMO

Spreading of Mycobacterium bovis causing animal tuberculosis (TB) at livestock-wildlife-environment interfaces remains a significant problem. Recently, we provided evidence of widespread environmental contamination of an endemic animal TB setting with viable and dormant M. bovis cells able to recover metabolic activity, making indirect transmission via environmental contamination plausible. We now report the first whole genome sequences of M. bovis recovered from the environment. We establish epidemiological links at the environment-animal interface by phylogenomic comparison of these M. bovis genomes with those isolated from livestock and wild ungulates from the same area. Environmental and animal genomes are highly intertwined and distribute similarly into the same M. bovis lineages, supporting several instances of environmental contamination. This study provides compelling evidence of M. bovis excretion into the environment and viability maintenance, supporting the environment as a potential source of new infection. These insights have clear implications for policy formulation, advocating environmental surveillance and an ecosystem perspective in TB control programs. ENVIRONMENTAL IMPLICATION: We report the first whole genome sequences of M. bovis from the environment and establish epidemiological links at the environment-animal interface, demonstrating close phylogenomic relatedness of animal and environmental M. bovis. Definitive evidence of M. bovis excretion into the environment with viability maintenance is provided, supporting the environment as a potential source of new infection. Implications of this work include methodological innovations offering a tool to resolve indirect transmission chains and support customized biosecurity measures. Policy formulation aiming at the control of animal tuberculosis and cost mitigation should consider these findings, encouraging environmental surveillance in official eradication programmes.

2.
ACS Appl Eng Mater ; 2(4): 1170-1189, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38693992

RESUMO

The expansion of the Internet of Things market and the proliferation of wearable technologies have generated a significant demand for textile-based energy storage systems. This work reports the engineered design of hybrid electrode nanomaterials of N-doped carbon nanotubes (CNT-N) functionalized with two types of manganese oxides (MOs)-birnessite (MnO2) and hausmannite (Mn3O4)-and their application in solid-state textile-based hybrid supercapacitors (SCs). A versatile citric acid-mediated eco-friendly one-pot aqueous precipitation process is proposed for the fabrication of the hybrids. Remarkably, different types of MOs were obtained by simply changing the reaction temperature from room temperature to 100 °C, without any post-thermal treatment. Asymmetric textile SCs were developed using cotton fabrics coated with CNT-N and the hybrids as textile electrodes, and poly(vinyl) alcohol/orthophosphoric acid as the solid-gel electrolyte. The asymmetric devices presented enhanced energy storage performance relative to the symmetric device based on CNT-N and excellent cycling stability (>96%) after 8000 charge/discharge cycles owing to synergistic effects between CNT-N and the MOs, which endowed nonfaradaic and pseudocapacitive features to the SCs. The asymmetric SC based on CNT-N@MnO2 featured 47% higher energy density and comparable power density to the symmetric CNT-N-based device (8.70 W h cm-2 at 309.01 µW cm-2 vs. 5.93 W h cm-2 at 346.58 µW cm-2). The engineered hybrid CNT-N@MO nanomaterials and the eco-friendly citric acid-assisted one-pot precipitation route open promising prospects not only for energy storage, but also for (photo)(electro)catalysis, wastewater treatment, and (bio)sensing.

3.
Nanomaterials (Basel) ; 14(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38668215

RESUMO

We report a joint high-pressure experimental and theoretical study of the structural, vibrational, and photoluminescent properties of pure and Eu3+-doped cubic Y2O3 nanoparticles with two very different average particle sizes. We compare the results of synchrotron X-ray diffraction, Raman scattering, and photoluminescence measurements in nanoparticles with ab initio density-functional simulations in bulk material with the aim to understand the influence of the average particle size on the properties of pure and doped Y2O3 nanoparticles under compression. We observe that the high-pressure phase behavior of Y2O3 nanoparticles depends on the average particle size, but in a different way to that previously reported. Nanoparticles with an average particle size of ~37 nm show the same pressure-induced phase transition sequence on upstroke and downstroke as the bulk sample; however, nanoparticles with an average particle size of ~6 nm undergo an irreversible pressure-induced amorphization above 16 GPa that is completed above 24 GPa. On downstroke, 6 nm nanoparticles likely consist of an amorphous phase.

4.
Int J Mol Sci ; 25(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38612679

RESUMO

Epidemiological surveillance of animal tuberculosis (TB) based on whole genome sequencing (WGS) of Mycobacterium bovis has recently gained track due to its high resolution to identify infection sources, characterize the pathogen population structure, and facilitate contact tracing. However, the workflow from bacterial isolation to sequence data analysis has several technical challenges that may severely impact the power to understand the epidemiological scenario and inform outbreak response. While trying to use archived DNA from cultured samples obtained during routine official surveillance of animal TB in Portugal, we struggled against three major challenges: the low amount of M. bovis DNA obtained from routinely processed animal samples; the lack of purity of M. bovis DNA, i.e., high levels of contamination with DNA from other organisms; and the co-occurrence of more than one M. bovis strain per sample (within-host mixed infection). The loss of isolated genomes generates missed links in transmission chain reconstruction, hampering the biological and epidemiological interpretation of data as a whole. Upon identification of these challenges, we implemented an integrated solution framework based on whole genome amplification and a dedicated computational pipeline to minimize their effects and recover as many genomes as possible. With the approaches described herein, we were able to recover 62 out of 100 samples that would have otherwise been lost. Based on these results, we discuss adjustments that should be made in official and research laboratories to facilitate the sequential implementation of bacteriological culture, PCR, downstream genomics, and computational-based methods. All of this in a time frame supporting data-driven intervention.


Assuntos
Coinfecção , Mycobacterium bovis , Tuberculose , Animais , Mycobacterium bovis/genética , Tuberculose/epidemiologia , Tuberculose/veterinária , DNA , Genômica
5.
Cereb Cortex ; 34(3)2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38501383

RESUMO

A key question in research on the neurobiology of language is to which extent the language production and comprehension systems share neural infrastructure, but this question has not been addressed in the context of conversation. We utilized a public fMRI dataset where 24 participants engaged in unscripted conversations with a confederate outside the scanner, via an audio-video link. We provide evidence indicating that the two systems share neural infrastructure in the left-lateralized perisylvian language network, but diverge regarding the level of activation in regions within the network. Activity in the left inferior frontal gyrus was stronger in production compared to comprehension, while comprehension showed stronger recruitment of the left anterior middle temporal gyrus and superior temporal sulcus, compared to production. Although our results are reminiscent of the classical Broca-Wernicke model, the anterior (rather than posterior) temporal activation is a notable difference from that model. This is one of the findings that may be a consequence of the conversational setting, another being that conversational production activated what we interpret as higher-level socio-pragmatic processes. In conclusion, we present evidence for partial overlap and functional asymmetry of the neural infrastructure of production and comprehension, in the above-mentioned frontal vs temporal regions during conversation.


Assuntos
Compreensão , Imageamento por Ressonância Magnética , Humanos , Compreensão/fisiologia , Imageamento por Ressonância Magnética/métodos , Comunicação , Idioma , Córtex Pré-Frontal , Mapeamento Encefálico
6.
EPMA J ; 15(1): 135-148, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38463621

RESUMO

Multidisciplinary team from three universities based in the "Centro" Region of Portugal developed diverse approaches as parts of a project dedicated to enhancing and expanding Predictive, Preventive, and Personalized Medicine (3PM) in the Region. In a sense, outcomes acted as a proof-of-concept, in that they demonstrated the feasibility, but also the relevance of the approaches. The accomplishments comprise defining a new regional strategy for implementing 3PM within the Region, training of human resources in genomic sequencing, and generating good practices handbooks dedicated to diagnostic testing via next-generation sequencing, to legal and ethical concerns, and to knowledge transfer and entrepreneurship, aimed at increasing literacy on 3PM approaches. Further approaches also included support for entrepreneurship development and start-ups, and diverse and relevant initiatives aimed at increasing literacy relevant to 3PM. Efforts to enhance literacy encompassed citizens across the board, from patients and high school students to health professionals and health students. This focus on empowerment through literacy involved a variety of initiatives, including the creation of an illustrated book on genomics and the production of two theater plays centered on genetics. Additionally, authors stressed that genomic tools are relevant, but they are not the only resources 3PM is based on. Thus, they defend that other initiatives intended to enable citizens to take 3PM should include multi-omics and, having in mind the socio-economic burden of chronic diseases, suboptimal health status approaches in the 3PM framework should also be considered, in order to anticipate medical intervention in the subclinical phase. Supplementary Information: The online version contains supplementary material available at 10.1007/s13167-024-00353-9.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38346488

RESUMO

OBJECTIVES: To compare the hearing outcomes of ossicular chain reconstruction using bone cement versus other materials such as prostheses and autografts. METHODS: This study included articles that compared hearing outcomes in patients with conductive hearing loss who underwent stapes revision surgery or chronic otitis media surgery. A systematic search for articles from January 2000 to February 2022 was conducted in Medline, Embase, and Cochrane Library databases. Only articles in English were included. An effective postoperative air-bone gap (ABG) was defined as ≤20 dB. A bias assessment tool was developed according to Cochrane guidelines, and the chi-square test was used to evaluate the mean age of the samples. RESULTS: Of the 418 studies that met the selection criteria, only seven were eligible for this study, consisting of 187 patients in the bone cement group and 173 in the non-bone cement group. Ossiculoplasty using bone cement yielded significantly better results, with a combined odds ratio (OR) of 2.03 (95% CI: 1.16-3.55, p = 0.01). CONCLUSIONS: The results of this study suggest that the effectiveness of bone cement in ossiculoplasty was greater than that of other materials in chronic otitis media surgery or stapes revision surgery, with a higher number of patients achieving ABG ≤20 dB.

8.
Materials (Basel) ; 17(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38399050

RESUMO

Two-dimensional (2D) nanostructures of aluminum nitride (AlN) and gallium nitride (GaN), called nanosheets, have a graphene-like atomic arrangement and represent novel materials with important upcoming applications in the fields of flexible electronics, optoelectronics, and strain engineering, among others. Knowledge of their mechanical behavior is key to the correct design and enhanced functioning of advanced 2D devices and systems based on aluminum nitride and gallium nitride nanosheets. With this background, the surface Young's and shear moduli of AlN and GaN nanosheets over a wide range of aspect ratios were assessed using the nanoscale continuum model (NCM), also known as the molecular structural mechanics (MSM) approach. The NCM/MSM approach uses elastic beam elements to represent interatomic bonds and allows the elastic moduli of nanosheets to be evaluated in a simple way. The surface Young's and shear moduli calculated in the current study contribute to building a reference for the evaluation of the elastic moduli of AlN and GaN nanosheets using the theoretical method. The results show that an analytical methodology can be used to assess the Young's and shear moduli of aluminum nitride and gallium nitride nanosheets without the need for numerical simulation. An exploratory study was performed to adjust the input parameters of the numerical simulation, which led to good agreement with the results of elastic moduli available in the literature. The limitations of this method are also discussed.

9.
Animals (Basel) ; 14(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38338000

RESUMO

The tadpole shrimp Triops longicaudatus is a freshwater crustacean with fast embryonic and larval development, short life cycle, and high fecundity. They are very active swimmers of a reasonable size, easy to spot and record. Such characteristics make it a promising candidate as an experimental model in ecotoxicology to evaluate the effects of aquatic pollutants, particularly using its locomotor behavior as an endpoint. To evaluate the sensitivity of T. longicaudatus and develop endpoints of interest, we conducted exposure experiments with lethal and sub-lethal concentrations of potassium dichromate, a compound known for its ecotoxicological importance and as a hexavalent chromium source. The endpoints evaluated were mortality, growth, sexual maturation, reproductive output, cholinesterase activity and locomotor/swimming behavior. The 96 h median lethal concentration was found to be 65 µg/L. Furthermore, exposure to potassium dichromate at higher concentrations had a significant negative impact on the growth rate of T. longicaudatus in terms of both body mass and length. The time for maturation was also delayed at higher concentrations. In addition, locomotor behavior allowed for the discrimination of all tested chromium concentrations and the control group and from each other, proving to be the most sensitive endpoint. Overall, the data support the potential of T. longicaudatus as a model for ecotoxicity testing, using apical endpoints with impact at the population level; in particular, results suggest that behavior assessments in this species might be useful for detecting hazardous compounds in environmental monitoring of freshwater ecosystems.

10.
Cureus ; 16(1): e52670, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38380189

RESUMO

Anorexia nervosa (AN) belongs to the spectrum of food disorders and affects approximately 2.9 million people worldwide. It is responsible for numerous and serious medical complications. Osteoporosis is a common complication, and the decrease in bone mineral density (BMD) is one of the few potentially irreversible consequences of AN. When associated with AN, it can manifest at a very young age, possibly leading to irreparable damage. We describe the case of a 30-year-old woman with a one-year evolution diagnosis of AN, complaining of back pain. Physical examination revealed a slight elevation of the right shoulder and pain at compression of paravertebral right dorsal musculature with a palpable strained muscle. Full-length X-ray imaging of the dorsal spine revealed a slight dextroconvex dorsolumbar scoliosis. A dorsal spine computerized tomography (CT) was performed, confirming a fracture of the upper platform of the sixth dorsal vertebrae. Osteodensitometry showed lumbar spine osteoporosis and femoral osteopenia. The decrease in BMD and, later on, the development of osteoporosis can occur in both types of AN. It is a severe complication that affects up to 50% of these patients. It can be irreversible and increase the lifetime risk of bone fractures and, therefore, morbimortality. Low body weight and body mass index (BMI) strongly correlate with the decrease in BMD. Treatment of osteoporosis associated with AN is not standardized and clearly labeled. Weight gain is described as the strategy with the most impact in reversing the loss of bone mass and increasing the BMD. The regularization of gonadal function also seems to independently potentiate the increase of BMD. The occurrence of long bone and vertebrae fractures frequently results in a decrease in height and chronic back pain, culminating in greater morbimortality and healthcare costs. This clinical case aims to show theclose relationship between restrictive food disorders and the decrease of BMD and the subsequent development of osteoporosis and its complications. Although rare in young and healthy people, when associated with restrictive food disorders, it should raise a red flag in its clinical evaluation. Preventing osteoporosis development and reduction of fracture risk in this population is essential. The current absence of consistent evidence regarding screening of osteoporosis in this particular group should raise awareness and promote further larger-scale studies to establish standardized recommendations concerning not only screening but also pharmacological treatment of osteoporosis in patients with AN.

11.
Acta Med Port ; 37(1): 27-35, 2024 Jan 03.
Artigo em Português | MEDLINE | ID: mdl-38183233

RESUMO

INTRODUCTION: Nutrition is a cornerstone of diabetes mellitus prevention and management; therefore, it is essential to enable patients to adopt healthy eating habits. Previous studies have not yet documented the main errors in the eating habits of Portuguese people with type 2 diabetes mellitus. This study aims to identify the main errors in the eating habits of people living with type 2 diabetes mellitus in Portugal and to evaluate its associations with sociodemographic variables. METHODS: Cross-sectional multicentric study in a convenience sample of people with type 2 diabetes mellitus in Primary Health Care Units. The UK Diabetes and Diet Questionnaire (UKDDQ) - translated and adapted, was applied from July to October 2022. Descriptive and inferential statistical analyses were conducted. RESULTS: Of the 550 participants, 52.2% were female, 68.3% were 65 years or over, 55.8 % had an education level up to the fourth grade, 24.7% had economic deprivation, and the mean time since diagnosis was 10.60 ± 8.13 years. Only 36.2% of the sample had a healthy UKDDQ score. Less than 50% of the sample had healthy scores for the items "high-fiber rice or pasta", "high-fiber bread", "butter, margarine and vegetable oils" and "vegetables and pulses". Only 8.9% of the sample had a healthy consumption of fiber. About 70.4% reported healthy scores for the consumption of "high-added-sugar foods" and 54.7% for "high-saturated fat". A statistically significant weak positive correlation was found between the UKDDQ score and age (ρ = 0.201, p < 0.001) with a more frequent choice of healthy foods with increasing age. Female respondents reported healthier habits, particularly in the consumption of "high-saturated fat" and "high-fiber foods". CONCLUSION: The majority of our sample did not take advantage of the potential benefits of healthy eating habits. The main food groups whose consumption should be emphasized or discouraged were individualized, particularly the need to encourage the consumption of high-fiber foods. Targeted educational actions must focus especially on younger and/or male patients.


Introdução: A nutrição é uma área de intervenção na prevenção e gestão da diabetes mellitus; por isso, é fulcral promover a capacitação da população para a adoção de hábitos alimentares saudáveis. Ainda que existam alguns estudos nesta área, não se conhecem os principais erros nos hábitos alimentares das pessoas com diabetes em Portugal. Os objetivos deste estudo foram identificar os principais erros nos hábitos alimentares das pessoas com diabetes mellitus tipo 2 em Portugal e avaliar a sua relação com variáveis sociodemográficas. Métodos: Estudo transversal multicêntrico, em amostra de conveniência de pessoas com diabetes mellitus tipo 2 seguidas em Unidades de Cuidados de Saúde Primários. Aplicação do UK Diabetes and Diet Questionnaire (UKDDQ) ­ traduzido e adaptado, de julho a outubro de 2022. Análise estatística descritiva e inferencial. Resultados: Amostra de 550 participantes, 52,2% do sexo feminino, 68,3% com 65 anos ou mais, 55,8% com nível de escolaridade igual ou inferior ao 1.º ciclo do ensino básico, 24,7% com insuficiência económica e tempo desde o diagnóstico médio de 10,60 ± 8,13 anos. Apenas 36,2% da amostra obteve um score UKDDQ considerado saudável. Menos de 50% obteve scores saudáveis para os itens "arroz ou massa ricos em fibras", "pão integral", "manteiga, margarina e óleos vegetais" e "vegetais e leguminosas". Somente 8,9% da amostra obteve score saudável para o consumo de fibras. Cerca de 70,4% obteve score saudável para o consumo de açúcares livres e 54,7% para o consumo de ácidos gordos saturados. Verificou-se a existência de uma correlação com significado estatístico positiva fraca entre o score UKDDQ e a idade (ρ = 0,201, p < 0,001), com escolha mais frequente de alimentos saudáveis com o aumentar da idade. As pessoas do sexo feminino reportaram hábitos alimentares mais saudáveis, particularmente no consumo de fibras e ácidos gordos saturados. Conclusão: A maior parte da nossa amostra não usufruiu do potencial efeito positivo de uma alimentação saudável. Individualizam-se grupos de alimentos cujos consumos devem ser enfatizados ou desencorajados, particularmente, a necessidade de incentivar o consumo de alimentos ricos em fibra. Ações educacionais dirigidas devem ter especial foco em pessoas mais jovens e/ou do sexo masculino.


Assuntos
Diabetes Mellitus Tipo 2 , Dieta , Feminino , Humanos , Masculino , Estudos Transversais , Portugal
12.
Small ; 20(12): e2307178, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37950402

RESUMO

This work reports the rational design and fabrication of magneto-active microfiber meshes with controlled hexagonal microstructures via melt electrowriting (MEW) of a magnetized polycaprolactone-based composite. In situ iron oxide nanoparticle deposition on oxidized graphene yields homogeneously dispersed magnetic particles with sizes above 0.5 µm and low aspect ratio, preventing cellular internalization and toxicity. With these fillers, homogeneous magnetic composites with high magnetic content (up to 20 weight %) are obtained and processed in a solvent-free manner for the first time. MEW of magnetic composites enabled the creation of skeletal muscle-inspired design of hexagonal scaffolds with tunable fiber diameter, reconfigurable modularity, and zonal distribution of magneto-active and nonactive material, with elastic tensile deformability. External magnetic fields below 300 mT are sufficient to trigger out-of-plane reversible deformation. In vitro culture of C2C12 myoblasts on three-dimensional (3D) Matrigel/collagen/MEW scaffolds showed that microfibers guided the formation of 3D myotube architectures, and the presence of magnetic particles does not significantly affect viability or differentiation rates after 8 days. Centimeter-sized skeletal muscle constructs allowed for reversible, continued, and dynamic magneto-mechanical stimulation. Overall, these innovative microfiber scaffolds provide magnetically deformable platforms suitable for dynamic culture of skeletal muscle, offering potential for in vitro disease modeling.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Músculo Esquelético , Impressão Tridimensional
13.
Endocrine ; 83(2): 302-321, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37658244

RESUMO

PURPOSE: Melatonin supplementation has been disclosed as an ergogenic substance. However, the effectiveness of melatonin supplementation in healthy subjects has not been systematically investigated. The present study analyzed the effects of melatonin supplementation on physical performance and recovery. In addition, it was investigated whether exercise bout or training alter melatonin secretion in athletes and exercise practitioners. METHODS: This systematic review and meta-analysis were conducted and reported according to the guidelines outlined in the PRISMA statement. Based on the search and inclusion criteria, 21 studies were included in the systematic review, and 19 were included in the meta-analysis. RESULTS: Melatonin supplementation did not affect aerobic performance relative to time trial (-0.04; 95% CI: -0.51 to 0.44) and relative to VO2 (0.00; 95% CI: -0.57 to 0.57). Also, melatonin supplementation did not affect strength performance (0.19; 95% CI: -0.28 to 0.65). Only Glutathione Peroxidase (GPx) secretion increased after melatonin supplementation (1.40; 95% CI: 0.29 to 2.51). Post-exercise melatonin secretion was not changed immediately after an exercise session (0.56; 95% CI: -0.29 to 1.41) and 60 min after exercise (0.56; 95% CI: -0.29 to 1.41). CONCLUSION: The data indicate that melatonin is not an ergogenic hormone. In contrast, melatonin supplementation improves post-exercise recovery, even without altering its secretion.


Assuntos
Melatonina , Substâncias para Melhoria do Desempenho , Humanos , Suplementos Nutricionais , Exercício Físico , Recuperação após o Exercício
14.
Br J Nutr ; 131(5): 829-840, 2024 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-37869973

RESUMO

Plant-based diets have emerged as athletic performance enhancers for various types of exercise. Therefore, the present study evaluated the effectiveness of plant-based diets on aerobic and strength/power performances, as well as on BMI of physically active individuals. This systematic review and meta-analysis was conducted and reported according to the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. A systematic search of electronic databases, including PubMed, Web of Science and SPORTDiscus, was performed. On the basis of the search and inclusion criteria, four and six studies evaluating the effects of plant-based diets on aerobic and strength/power performances in humans were, respectively, included in the systematic review and meta-analysis. Plant-based diets had a moderate but positive effect on aerobic performance (0·55; 95 % CI 0·29, 0·81) and no effect on strength/power performance (-0·30; 95 % CI -0·67, 0·07). The altogether analyses of both aerobic and strength/power exercises revealed that athletic performance was unchanged (0·01; 95 % CI -0·21, 0·22) in athletes who adopted plant-based diets. However, a small negative effect on BMI (-0·27; 95 % CI -0·40, -0·15) was induced by these diets. The results indicate that plant-based diets have the potential to exclusively assist aerobic performance. On the other hand, these diets do not jeopardise strength/power performance. Overall, the predicted effects of plant-based diets on physical performance are impactless, even though the BMI of their adherents is reduced.


Assuntos
Desempenho Atlético , Dieta Baseada em Plantas , Humanos , Dieta , Exercício Físico , Terapia por Exercício , Força Muscular
15.
J Toxicol Environ Health A ; 87(1): 33-46, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-37886814

RESUMO

Hydroxycoumarins are an important source of biologically active compounds. Previous studies have shown that the number and position of the hydroxyl substituents in the scaffold play an important role for the observed biological activity. In the present study, 3-(3-hydroxyphenyl)-7-hydroxycoumarin was synthesized, and potential cytogenotoxic effects determined in human HepG2/C3A cells displaying phase 1 and phase 2 enzymes (metabolizing cell ability) and compared to human peripheral blood mononuclear cells (PBMC) without xenobiotics metabolizing capacity. Cell viability was determined with concentrations between 0.01 and 10 µg/ml of 3-(3-hydroxyphenyl)-7-hydroxycoumarin using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) and trypan blue tests. Genotoxicity was determined utilizing the comet assay, and the clastogenic/aneugenic potential employing the micronucleus (MN) test. The results of the in vitro cytotoxicity assays showed a significant decrease in cell viability of PBMC following exposure to 10 µg/ml concentration of the studied compound after 48 and 72 hr. Comet assay observations noted significant DNA damage in PBMC after 4 hr treatment. No marked cytogenotoxic effects were found in HepG2/C3A cells. No chromosomal mutations were observed in both cell lines. It is important to note that 3-(3-hydroxyphenyl)-7-hydroxycoumarin may exert beneficial pharmacological actions at the low micromolar range and with half-life less than 24 hr. Therefore, the results obtained encourage the continuation of studies on this new molecule for medicinal purposes, but its potential toxicity at higher concentrations and longer exposure times needs to be investigated in further studies.


Assuntos
Dano ao DNA , Leucócitos Mononucleares , Humanos , Ensaio Cometa/métodos , Testes para Micronúcleos/métodos , Morte Celular , Umbeliferonas/farmacologia
16.
Support Care Cancer ; 31(12): 687, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37947888

RESUMO

PURPOSE: The prompt initiation of a betalactam antibiotic in febrile neutropenic patients is considered standard of care, while the empiric use of vancomycin is recommended by guidelines in specific situations, with a low level of evidence. The objective of this study was to assess the utilization of vancomycin in the management of febrile neutropenia within four Brazilian medical centers that implemented more stringent criteria for its administration. METHODS: A comprehensive retrospective analysis was performed encompassing all instances of febrile neutropenia observed during the period from 2013 to 2019. The primary focus was to identify the reasons for initiating vancomycin therapy. RESULTS: A total of 536 consecutive episodes of febrile neutropenia were documented, involving 384 patients with a median age of 52 years (range 18-86). Chemotherapy preceded febrile neutropenia in 59.7% of cases, while 40.3% occurred after hematopoietic stem cell transplantation. The most prevalent underlying diseases were acute myeloid leukemia (26.5%) and non-Hodgkin's lymphoma (22%). According to international guidelines, vancomycin should have been initiated at the onset of fever in 145 episodes (27%); however, it was administered in only 27 cases (5.0%). Three episodes were associated with Staphylococcus aureus bacteremia, two of which were methicillin resistant. The 15-day and 30-day mortality rates were 5.0% and 9.9%, respectively. CONCLUSIONS: The results of this study underscore the notably low utilization rate of vancomycin in cases of febrile neutropenia, despite clear indications outlined in established guidelines. These findings emphasize the importance of carefully implementing guideline recommendations, considering local epidemiological factors, especially when the strength of recommendation is weak.


Assuntos
Neutropenia Febril , Vancomicina , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Vancomicina/uso terapêutico , Vancomicina/efeitos adversos , Antibacterianos , Estudos Retrospectivos , Brasil , Febre/etiologia , Febre/induzido quimicamente , Neutropenia Febril/tratamento farmacológico , Neutropenia Febril/induzido quimicamente
17.
PeerJ ; 11: e16460, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025752

RESUMO

Background: Wildlife farming can be an important but complex tool for conservation. To achieve conservation benefits, wildlife farming should meet a variety of criteria, including traceability conditions to identify the animals' origin. The traditional techniques for discriminating between wild and captive animals may be insufficient to prevent doubts or misdeclaration, especially when labels are not expected or mandatory. There is a pressing need to develop more accurate techniques to discriminate between wild and captive animals and their products. Stable isotope analysis has been used to identify animal provenance, and some studies have successfully demonstrated its potential to differentiate wild from captive animals. In this literature review, we examined an extensive collection of publications to develop an overall picture of the application of stable isotopes to distinguish between wild and captive animals focusing on evaluating the patterns and potential of this tool. Survey methodology: We searched peer-reviewed publications in the Web of Science database and the references list from the main studies on the subject. We selected and analyzed 47 studies that used δ13C, δ15N, δ2H, δ18O, and δ34S in tissues from fish, amphibians, reptiles, birds, and mammals. We built a database from the isotope ratios and metadata extracted from the publications. Results: Studies have been using stable isotopes in wild and captive animals worldwide, with a particular concentration in Europe, covering all main vertebrate groups. A total of 80.8% of the studies combined stable isotopes of carbon and nitrogen, and 88.2% used at least one of those elements. Fish is the most studied group, while amphibians are the least. Muscle and inert organic structures were the most analyzed tissues (46.81% and 42.55%). δ13C and δ15N standard deviation and range were significantly higher in the wild than in captive animals, suggesting a more variable diet in the first group. δ13C tended to be higher in wild fishes and in captive mammals, birds, reptiles, and amphibians. δ15N was higher in the wild terrestrial animals when controlling for diet. Only 5.7% of the studies failed to differentiate wild and captive animals using stable isotopes. Conclusions: This review reveals that SIA can help distinguish between wild and captive in different vertebrate groups, rearing conditions, and methodological designs. Some aspects should be carefully considered to use the methodology properly, such as the wild and captivity conditions, the tissue analyzed, and how homogeneous the samples are. Despite the increased use of SIA to distinguish wild from captive animals, some gaps remain since some taxonomic groups (e.g., amphibians), countries (e.g., Africa), and isotopes (e.g., δ2H, δ18O, and δ34S) have been little studied.


Assuntos
Animais Selvagens , Carbono , Animais , Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , Peixes , Mamíferos
18.
Polymers (Basel) ; 15(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38006116

RESUMO

Gold nanoclusters (AuNCs) with fluorescence in the Near Infrared (NIR) by both one- and two-photon electronic excitation were incorporated in mesoporous silica nanoparticles (MSNs) using a novel one-pot synthesis procedure where the condensation polymerization of alkoxysilane monomers in the presence of the AuNCs and a surfactant produced hybrid MSNs of 49 nm diameter. This method was further developed to prepare 30 nm diameter nanocomposite particles with simultaneous NIR fluorescence and superparamagnetic properties, with a core composed of superparamagnetic manganese (II) ferrite nanoparticles (MnFe2O4) coated with a thin silica layer, and a shell of mesoporous silica decorated with AuNCs. The nanocomposite particles feature NIR-photoluminescence with 0.6% quantum yield and large Stokes shift (290 nm), and superparamagnetic response at 300 K, with a saturation magnetization of 13.4 emu g-1. The conjugation of NIR photoluminescence and superparamagnetic properties in the biocompatible nanocomposite has high potential for application in multimodal bioimaging.

19.
Vet Sci ; 10(11)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37999454

RESUMO

Cytospins are important for evaluating fluids with very low cellularity such as cerebrospinal fluid (CSF). The aim of this study was to compare the CSF cytospin preparations obtained from automated and manual cytocentrifugation methods. A prospective case series was performed to analyze canine CSF samples using both centrifugation methods. The cytospins were processed within 30-60 min and prepared simultaneously in a conventional automated cytocentrifuge and in an in-house manual cytocentrifuge, using a fixed volume of CSF fluid. The cellularity, differential cell count and the proportion of cell artifacts (pseudopods and vacuolization) were blindly assessed in the cytospin preparations obtained using the two methods. The agreement and correlation between both methods were analyzed. There were 55 dogs enrolled (48 prospectively and 7 retrospectively) in the study. 38 dogs had normal total nucleated cell counts, while 17 had pleocytosis. Automated and manual cytocentrifugation had similar cell yields, and no significant differences in differential cell counts or the presence of artifacts existed between both methods. In cases with pleocytosis, the cytologic diagnosis obtained using each method was similar. Manual cytocentrifugation of CSF is a reliable and economic method designed for routine clinical practice. Its use reduces the specimen deterioration related to processing and analysis delays when samples are transported to external laboratories for evaluation.

20.
Nanomaterials (Basel) ; 13(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37887910

RESUMO

Hexagonal boron nitride (h-BN) nanosheets are attractive materials for various applications that require efficient heat transfer, surface adsorption capability, biocompatibility, and flexibility, such as optoelectronics and power electronics devices, nanoelectromechanical systems, and aerospace industry. Knowledge of the mechanical behavior of boron nitride nanosheets is necessary to achieve accurate design and optimal performance of h-BN-based nanodevices and nanosystems. In this context, the Young's and shear moduli and Poisson's ratio of square and rectangular boron nitride nanosheets were evaluated using the nanoscale continuum modeling approach, also known as molecular structural mechanics. The latter allows robust and rapid assessment of the elastic constants of nanostructures with graphene-like lattices. To date, there is a lack of systematic research regarding the influence of input parameters for numerical simulation, loading conditions, size, and aspect ratio on the elastic properties of the h-BN nanosheets. The current study contributes to filling this gap. The results allow, on the one hand, to point out the input parameters that lead to better agreement with those available in the literature. On the other hand, the Young's and shear moduli, and Poisson's ratio calculated in the present work contribute to a benchmark for the evaluation of elastic constants of h-BN nanosheets using theoretical methods.

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