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1.
Radiology ; 310(2): e232030, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38411520

RESUMO

According to the World Health Organization, climate change is the single biggest health threat facing humanity. The global health care system, including medical imaging, must manage the health effects of climate change while at the same time addressing the large amount of greenhouse gas (GHG) emissions generated in the delivery of care. Data centers and computational efforts are increasingly large contributors to GHG emissions in radiology. This is due to the explosive increase in big data and artificial intelligence (AI) applications that have resulted in large energy requirements for developing and deploying AI models. However, AI also has the potential to improve environmental sustainability in medical imaging. For example, use of AI can shorten MRI scan times with accelerated acquisition times, improve the scheduling efficiency of scanners, and optimize the use of decision-support tools to reduce low-value imaging. The purpose of this Radiology in Focus article is to discuss this duality at the intersection of environmental sustainability and AI in radiology. Further discussed are strategies and opportunities to decrease AI-related emissions and to leverage AI to improve sustainability in radiology, with a focus on health equity. Co-benefits of these strategies are explored, including lower cost and improved patient outcomes. Finally, knowledge gaps and areas for future research are highlighted.


Assuntos
Inteligência Artificial , Radiologia , Humanos , Radiografia , Big Data , Mudança Climática
2.
Mol Pharm ; 21(1): 38-52, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37646561

RESUMO

The cisplatin encapsulation into carbon nanohorns (CNH) is a promising nanoformulation to circumvent the drug dissipation and to specifically accumulate it in tumor sites. Herein, biased molecular dynamics simulations were used to analyze the transmembrane transport of the CNH loaded with cisplatin through a breast cancer cell membrane prototype. The simulations revealed a four-stage mechanism: approach, insertion, permeation, and internalization. Despite the lowest structural disturbance of the membrane provided by the nanocarrier, the average free energy barrier for the translocation was 55.2 kcal mol-1, suggesting that the passive process is kinetically unfavorable. In contrast, the free energy profiles revealed potential wells of -6.8 kcal mol-1 along the insertion stage in the polar heads region of the membrane, which might enhance the retention of the drug in tumor sites; therefore, the most likely cisplatin delivery mechanism should involve the adsorption and retention of CNH on the surface of cancer cells, allowing the loaded cisplatin be slowly released and passively transported through the cell membrane.


Assuntos
Neoplasias da Mama , Cisplatino , Humanos , Feminino , Cisplatino/química , Carbono , Neoplasias da Mama/tratamento farmacológico , Transporte Biológico , Membrana Celular
3.
J Insect Sci ; 24(2)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38442352

RESUMO

The shift to a pollen diet and the evolution of more highly organized societies, i.e., eusocial, were key milestones in bee diversification over their evolutionary history, culminating in a high dependence on feeding broods with a large variety of floral resources. Here, we hypothesized that obligatory eusocial bees have a wider diet diversity than their relatives with solitary lifestyles, and this would be related to colony size. To test both hypotheses, we surveyed diet breadth data (palynological analysis) based on the Shannon-Wiener index (H') for 85 bee taxa. We also obtained colony size for 47 eusocial bee species. These data were examined using phylogenetic comparative methods. The results support the generalist strategy as a derived trait for the bee taxa evaluated here. The dietary diversity of eusocial bees (H': 2.1, on average) was 67.5% higher than that of noneusocial bees (H': 1.21, on average). There was, however, no relationship between diet breadth and colony size, indicating that smaller colonies can harvest a pollen variety as diverse as larger colonies. Taken together, these results provide new insights into the impact of lifestyle on the diversity of collected pollen. Furthermore, this work sheds light on an advantage of living in more highly structured societies irrespective of the size of the colony.


Assuntos
Dieta , Pólen , Abelhas , Animais , Filogenia , Fenótipo
4.
Cladistics ; 39(3): 215-228, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36869732

RESUMO

All Epiponini wasps are polygynic, with multiple queens alternating over the colony cycle. There are several potential queens in the early stages of this cycle, but as it progresses, the number of queens is reduced. Because most individuals remain reproductively totipotent, there is great potential for conflicts over reproduction. Workers could have an advantage in controlling queen production because they are much more numerous than queens. Nevertheless, the queen selection process is little known for Epiponini. For this reason, we aimed to study the behaviour of queens and workers during queen selection in multiple species of Epiponini, integrate information from previous behavioural studies, and perform a comparative analysis to interpret changes evolutionarily. We conducted observations on nine species belonging to five genera: Brachygastra, Chartergellus, Metapolybia, Polybia and Protopolybia. Females were individually marked to make direct and video observations. Queen production was artificially induced. A total of 28 behaviours related to queen selection were identified. The most aggressive interactions between castes, such as bite and dart, were lost in the major lineages of Epiponini. Bending display I is an ancient behaviour used as the main dominance display. Behaviours exhibited by workers to test queen status arose in the common ancestor of the Epiponini and are not shared by other polistine wasps. Consequently, the act of workers testing queen status probably was present in the Epiponini ancestor. Ritualized test display and dominance behaviours are used in Epiponini as honest signals of the queen's reproductive potential instead of aggressive behaviours. Caste flexibility had already been suggested as the ground plan for Epiponini and is herein discussed as decisive for colony survival of swarm wasps, because it allows colonies to respond efficiently to different situations that may eventually arise.


Assuntos
Vespas , Humanos , Animais , Feminino , Vespas/genética , Comportamento Social , Reprodução , Agressão
5.
Ecol Appl ; 33(2): e2781, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36398791

RESUMO

Global demand for crops will continue increasing over the next few decades to cover both food and biofuel needs. This demand will put further pressure to expand arable land and replace natural habitats. However, we are only beginning to understand the combined effects of agrochemicals and land-use change on tropical freshwater biodiversity. In this study, we analyzed how pond-dwelling anuran larvae responded to pond characteristics, landscape composition, and agrochemical contamination in a sugarcane-dominated agroecosystem in Brazil. Then we used an information theoretical approach with generalized linear models to relate species richness and abundance to predictor variables. The variation in tadpole abundance was associated with both agrochemical concentration (e.g., ametryn, diuron, and malathion) and landscape variables (e.g., percentage of forest, percentage of agriculture, and distance to closest forest). The relationship between species abundance and agrochemicals was species-specific. For example, the abundances of Scinax fuscovarius and Physalaemus nattereri were negatively associated with ametryn, and Dendropsophus nanus was negatively associated with tebuthiuron, whereas that of Leptodactylus fuscus was positively associated with malathion. Conversely, species richness was associated with distance to forest fragments and aquatic vegetation heterogeneity, but not agrochemicals. Although we were unable to assign a specific mechanism to the variation in tadpole abundance based on field observations, the lower abundance of three species in ponds with high concentrations of agrochemicals suggest they negatively impact some frog species inhabiting agroecosystems. We recommend conserving ponds near forest fragments, with abundant stratified vegetation, and far from agrochemical runoffs to safeguard more sensitive pond-breeding species.


Assuntos
Saccharum , Animais , Malation , Melhoramento Vegetal , Ecossistema , Anuros , Biodiversidade , Larva
6.
Microb Ecol ; 85(2): 765-778, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35284961

RESUMO

We previously showed that colonies of thriving and non-thriving honeybees co-located in a single geographically isolated apiary harboured strikingly different microbiomes when sampled at a single time point in the honey season. Here, we profiled the microbiome in returning forager bees from 10 to 12 hives in each of 6 apiaries across the southern half of Ireland, at early, middle, and late time points in the 2019 honey production season. Despite the wide range of geographical locations and forage available, apiary site was not the strongest determinant of the honeybee microbiome. However, there was clear clustering of the honeybee microbiome by time point across all apiaries, independent of which apiary was sampled. The clustering of microbiome by time was weaker although still significant in three of the apiaries, which may be connected to their geographic location and other external factors. The potential forage effect was strongest at the second timepoint (June-July) when the apiaries also displayed greatest difference in microbiome diversity. We identified bacteria in the forager bee microbiome that correlated with hive health as measured by counts of larvae, bees, and honey production. These findings support the hypothesis that the global honeybee microbiome and its constituent species support thriving hives.


Assuntos
Microbiota , Abelhas , Animais , Estações do Ano , Larva , Bactérias , Irlanda
7.
J Chem Inf Model ; 63(19): 6141-6155, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37751589

RESUMO

Breast cancer is one of the most frequent modalities of cancer worldwide, with notable mortality. The medication based on platinum drugs (cisplatin (cddp), carboplatin (cpx), and oxaliplatin (oxa)) is a conventional chemotherapy despite severe side effects and the development of drug resistance. In order to provide a deeper molecular description of the influx and efflux processes of platinum drugs through breast cancer tissues, this study focuses on molecular dynamics (MD) simulations of the passive translocation process through a realistic plasma membrane prototype of human breast cancer cell (c_memb). The results showed that the permeation events were mainly mediated by neutral lipids (DOPC, DOPE, and cholesterol), producing a low and temporary membrane deformation. The drug insertion in the region of polar heads was the most favorable stage of the translocation mechanism, especially for cddp and oxa with potential wells of -8.6 and -9.8 kcal mol-1, respectively. However, the potentials of mean force (PMF) revealed unfavorable kinetics for the permeation of these drugs through lipid tails, with energy barriers of 28.3 (cddp), 32.2 (cpx), and 30.4 kcal mol-1 (oxa). The low permeability coefficients (P) of cpx and oxa, which were 3 and 1 orders of magnitude inferior than for cddp, resulted from the high energy barriers for their traslocation processes through the membrane. The obtained results provide a more accurate picture of the permeation of Pt(II)-based drugs through breast cancer cells, which may be relevant for the design and evaluation of new platinum complexes.

8.
Biometals ; 36(1): 49-66, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36282444

RESUMO

This study, performed during 2003-2005 and 2008-2009, investigated metals (Al, Fe, Ba, Zn, Mn, Cr, Cu, Ni, Cd) content in seston at Cabo Frio Bay, SE-Brazil. This study may serve as a baseline of seston metal distribution to guide biogeochemical and ecological models. The seston fractions (> 20 µm, > 64 µm, > 100 µm, and > 150 µm) were sampled in sub-surface horizontal hauls. Metals were determined by ICP-MS. The metals range: Al (62.5-56,867.6 µg g-1), Fe (23.5-25,384.0 µg g-1), Mn (2.7-336.8 µg g-1), Ba (< 0.005-356.3 µg g-1), Zn (0.5-94.2 µg g-1), Cr (0.7-35.5 µg g-1), Cu (4.3-41.7 µg g-1), Ni (< 0.005-19.1 µg g-1) and Cd (< 0.0004-2.4 µg g-1). Aluminium, Fe, Mn, Ba, and Zn showed significant differences (p < 0.05) between the seston fraction. The results obtained in this study suggest that the elements (Fe, Mn, Ba) in the seston were strongly influenced by the abiogenic source. In contrast, Zn, Cd, Cu, Cr, and Ni can be biogenic/anthropogenic sources. The significant positive linear correlation of Zn:P, Cd:P, and Cu:P can indicate an intracellular concentration higher than the external adsorption in the plankton community.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Baías , Brasil , Cádmio , Monitoramento Ambiental/métodos , Metais
9.
Ann Diagn Pathol ; 64: 152129, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36822052

RESUMO

INTRODUCTION: According to the World Health Organization's classification of endocrine tumors, papillary thyroid carcinoma (PTC) accounts for almost 90 % of malignant thyroid neoplasms. This study aimed to create a point system based on cytomorphological criteria for evaluating FNA products from thyroid nodules to predict the risk of papillary thyroid carcinomas. METHODS: This was an analytical observational study based on a retrospective analysis of cytological reports and surgical specimens from January 1, 2016, to December 31, 2021. Cytological slides were analyzed using the following ten variables: Nuclear Grooves; Intranuclear Pseudoinclusion; Cellularity; Colloid (Quantity); Clarified Chromatin; Overlapping nuclei; Irregular Nuclear Membrane; Multinucleated Giant Cells; Psamoma bodies; and Papillae. We categorized these variables quantitatively from zero to three points as follows: zero (absent), one (mild), two (moderate), and three (intense). RESULTS: Cytologies of 254 (4.9 %) cases were analyzed. The cut-off point was defined in this study as 6 ± 1 points. For the prediction of cases in benign, values < 5 points, malignant, values > 7 points and indeterminate, 5-7 points. Among the benign, there were 64 (69.5 %) cases <5 points, 17 (18.4 %) from 5 to 7 points and 11 (11.9 %) >7 points. Among the malignant ones, there were 12 (8.6 %) cases <5 points, 19 (13.6 %) from 5 to 7 points and 108 (77.6) >7 points. CONCLUSION: In this context, through the quantitative analysis of the ten suggested cytological variables, scored from 0 to 3, a final score > 7 is suspicious for malignancy, while a score < 5 is related to benign lesions.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/diagnóstico , Câncer Papilífero da Tireoide/patologia , Biópsia por Agulha Fina , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/diagnóstico
10.
Environ Monit Assess ; 195(6): 784, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37261565

RESUMO

Land cover changes threaten biodiversity and alter the geographic distribution of forests worldwide. Studies on this topic are important to establish conservation strategies and public policies. However, different studies may propose different spatial representations due to differences when identifying, classifying, and/or mapping the same vegetation formation, as observed for the Cocais Forest region. This palm-dominated ecosystem predominates the Brazilian mid-north region in an ecotone region with 3 of the 6 Brazilian biomes. In this study, we conducted a literature review of studies that delineated and mapped the Cocais Forest, aiming to compare different mapped regions and to establish a new distribution map integrating these spatial data. We found seven sources that revealed spatial divergences in identifying the spatial distribution of Cocais Forest, including its characteristics in terms of size and shape, which could affect the conservation, socioeconomic, and cultural policies and studies carried out on this emblematic vegetation formation and influence area. The delineation proposed by de Sousa Nascimento and Lima (Revista de Políticas Públicas 189-192, 2016) encompassed the largest area. In addition, there was a lack of consensus regarding the nomenclature for this ecosystem, and few works offered a detailed description of the mapping process. Despite the different spatial distributions found for the Cocais Forest, we succeeded in establishing a common area by overlapping individual maps, resulting in the identification of a core region exclusive located in the State of Maranhão.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental , Florestas , Biodiversidade , Árvores
11.
Mol Biol Evol ; 38(3): 1090-1100, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33179746

RESUMO

Incongruence among phylogenetic results has become a common occurrence in analyses of genome-scale data sets. Incongruence originates from uncertainty in underlying evolutionary processes (e.g., incomplete lineage sorting) and from difficulties in determining the best analytical approaches for each situation. To overcome these difficulties, more studies are needed that identify incongruences and demonstrate practical ways to confidently resolve them. Here, we present results of a phylogenomic study based on the analysis 197 taxa and 2,526 ultraconserved element (UCE) loci. We investigate evolutionary relationships of Eucerinae, a diverse subfamily of apid bees (relatives of honey bees and bumble bees) with >1,200 species. We sampled representatives of all tribes within the group and >80% of genera, including two mysterious South American genera, Chilimalopsis and Teratognatha. Initial analysis of the UCE data revealed two conflicting hypotheses for relationships among tribes. To resolve the incongruence, we tested concatenation and species tree approaches and used a variety of additional strategies including locus filtering, partitioned gene-trees searches, and gene-based topological tests. We show that within-locus partitioning improves gene tree and subsequent species-tree estimation, and that this approach, confidently resolves the incongruence observed in our data set. After exploring our proposed analytical strategy on eucerine bees, we validated its efficacy to resolve hard phylogenetic problems by implementing it on a published UCE data set of Adephaga (Insecta: Coleoptera). Our results provide a robust phylogenetic hypothesis for Eucerinae and demonstrate a practical strategy for resolving incongruence in other phylogenomic data sets.


Assuntos
Abelhas/genética , Técnicas Genéticas , Filogenia , Animais , Besouros/genética
12.
Syst Biol ; 70(2): 295-306, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32722788

RESUMO

It is widely recognized that different regions of a genome often have different evolutionary histories and that ignoring this variation when estimating phylogenies can be misleading. However, the extent to which this is also true for morphological data is still largely unknown. Discordance among morphological traits might plausibly arise due to either variable convergent selection pressures or else phenomena such as hemiplasy. Here, we investigate patterns of discordance among 282 morphological characters, which we scored for 50 bee species particularly targeting corbiculate bees, a group that includes the well-known eusocial honeybees and bumblebees. As a starting point for selecting the most meaningful partitions in the data, we grouped characters as morphological modules, highly integrated trait complexes that as a result of developmental constraints or coordinated selection we expect to share an evolutionary history and trajectory. In order to assess conflict and coherence across and within these morphological modules, we used recently developed approaches for computing Bayesian phylogenetic information allied with model comparisons using Bayes factors. We found that despite considerable conflict among morphological complexes, accounting for among-character and among-partition rate variation with individual gamma distributions, rate multipliers, and linked branch lengths can lead to coherent phylogenetic inference using morphological data. We suggest that evaluating information content and dissonance among partitions is a useful step in estimating phylogenies from morphological data, just as it is with molecular data. Furthermore, we argue that adopting emerging approaches for investigating dissonance in genomic datasets may provide new insights into the integration and evolution of anatomical complexes. [Apidae; entropy; morphological modules; phenotypic integration; phylogenetic information.].


Assuntos
Filogenia , Animais , Teorema de Bayes , Abelhas/genética
13.
Appl Microbiol Biotechnol ; 106(21): 6963-6976, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36197457

RESUMO

Papiliotrema laurentii, previously classified as Cryptococcus laurentii, is an oleaginous yeast that has been isolated from soil, plants, and agricultural and industrial residues. This variety of habitats reflects the diversity of carbon sources that it can metabolize, including monosaccharides, oligosaccharides, glycerol, organic acids, and oils. Compared to other oleaginous yeasts, such as Yarrowia lipolytica and Rhodotorula toruloides, there is little information regarding its genetic and physiological characteristics. From a biotechnological point of view, P. laurentii can produce surfactants, enzymes, and high concentrations of lipids, which can be used as feedstock for fatty acid-derived products. Moreover, it can be applied for the biocontrol of phytopathogenic fungi, contributing to quality maintenance in post- and pre-harvest fruits. It can also improve mycorrhizal colonization, nitrogen nutrition, and plant growth. P. laurentii is also capable of degrading polyester and diesel derivatives and acting in the bioremediation of heavy metals. In this review, we present the current knowledge about the basic and applied aspects of P. laurentii, underscoring its biotechnological potential and future perspectives. KEY POINTS: • The physiological characteristics of P. laurentii confer a wide range of biotechnological applications. • The regulation of the acetyl-CoA carboxylase in P. laurentii is different from most other oleaginous yeasts. • The GEM is a valuable tool to guide the construction of engineered P. laurentii strains with improved features for bio-based products.


Assuntos
Acetil-CoA Carboxilase , Yarrowia , Glicerol , Yarrowia/metabolismo , Ácidos Graxos/metabolismo , Nitrogênio , Carbono , Óleos , Solo , Monossacarídeos , Tensoativos , Poliésteres
14.
J Evol Biol ; 34(9): 1466-1476, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34331340

RESUMO

Ribosomal DNA (rDNA) loci are essential for cellular metabolism due to their participation in ribosome biogenesis. Although these genes have been widely cytogenetically mapped, the evolutionary mechanisms behind their variability in number and chromosomal location remain elusive, even in well-known biological groups, such as ants, bees and wasps (Insecta: Hymenoptera). To address this question in Hymenoptera and therefore advance the understanding of rDNA evolution in insects in general, we integrated molecular cytogenetic data, a phylogenomic framework, model-based predictions and genome sequencing. Hence, we assessed the main evolutionary trends shaping the chromosomal distribution of rDNA loci in Hymenoptera. We noticed the conservation of one site of rDNA per haploid genome, suggesting that a single 45S rDNA locus is the putative ancestral pattern for aculeate Hymenoptera. Moreover, our results highlighted a nonrandom distribution of rDNA in Hymenoptera karyotypes, as well as a lineage-specific preferential location. The proximal location of rDNA is favoured in species with multiple loci and in the two families of Hymenoptera that show the highest range of chromosome numbers: Formicidae and Vespidae. We propose that chromosome fissions have played a crucial role in the distribution pattern of rDNA loci through the evolutionary diversification of Hymenoptera. Moreover, our genomic analysis of two species, one with a single locus of rDNA and one with multiple loci, supported that loci multiplication is followed by sequence divergence. Our results provide detailed information about the number and chromosomal position of rDNA in Hymenoptera and, therefore, broaden our knowledge regarding rDNA evolutionary dynamics in insects.


Assuntos
Formigas , Vespas , Animais , Formigas/genética , Abelhas , DNA Ribossômico/genética , Cariótipo , Filogenia , Vespas/genética
15.
Cladistics ; 37(4): 423-441, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34478190

RESUMO

Neotropical swarm-founding wasps are divided into 19 genera in the tribe Epiponini (Vespidae, Polistinae). They display extensive variation in several colony-level traits that make them an attractive model system for reconstructing the evolution of social phenotypes, including caste dimorphism and nest architecture. Epiponini has been upheld as a solid monophyletic group in most phylogenetic analyses carried out so far, supported by molecular, morphological and behavioural data. Recent molecular studies, however, propose different relationships among the genera of swarm-founding wasps. This study is based on the most comprehensive epiponine sampling so far and was analyzed by combining morphological, nesting and molecular data. The resulting phylogenetic hypothesis shows many of the traditional clades but still impacts the way certain behavioural characters, such as nest structure and castes, evolved, and thus requires some re-interpretations. Angiopolybia as sister to the remaining Epiponini implies that nest envelopes and a casteless system are plesiomorphic in the tribe. Molecular dating points to an early tribal diversification during the Eocene (c. 55-38 Ma), with the major differentiation of current genera concentrated in the Oligocene/Miocene boundary.


Assuntos
Ovário/fisiologia , Filogenia , Comportamento Social , Evolução Social , Vespas/anatomia & histologia , Vespas/fisiologia , Animais , Feminino , Geografia , Ovário/anatomia & histologia , Reprodução
16.
Cell Biol Int ; 45(1): 92-106, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32991000

RESUMO

Imbalance of sexual steroids milieu and oxidative stress are often observed during aging and correlated to prostate disorders. Likewise, high-fat intake has been related to prostate damage and tumor development. Melatonin (MLT) is an antioxidant whose secretion decreases in elderly and is also suggested to protect the gland. This study evaluated the impact of a long-term high-fat diet during aging on prostate morphology and antioxidant system of rats and tested the effects of MLT supplementation under these conditions. Male rats were assigned into four groups: control, treated with MLT, high-fat diet and high-fat diet treated with MLT. The high-fat diet was provided from the 24th week of age, MLT from the 48th (100 µg/kg/day) and rats were euthanized at the 62nd week. The high-fat diet increased body weight, retroperitoneal fatness, glycaemia, and circulating estrogen levels. It aggravated the aging effects, leading to epithelial atrophy (∼32% reduction of epithelial height) and collagen fibers increase (83%). MLT alone did not alter biometric and physiological parameters, except for the prostate weight decrease, whereas it alleviated biometric as well as ameliorated acinar atrophy induced by high-lipid intake. Systemic oxidative stress increased, and prostatic glutathione peroxidase activity decreased fivefold with the high-fat diet despite the indole. Regardless of the diet, MLT triggered epithelial desquamation, reduced androgen receptor-positive cells, increased smooth muscle layer thickness (12%), decreased at least 50% corpora amylacea formation, and stimulated prostatic gluthatione-S-transferase activity. In conclusion, MLT partially recovered prostate damage induced by aging and the long-term high-fat diet and ameliorated degenerative prostate alterations.


Assuntos
Melatonina/farmacologia , Próstata/patologia , Células Acinares/efeitos dos fármacos , Células Acinares/patologia , Adiposidade/efeitos dos fármacos , Animais , Colágeno/metabolismo , Dieta Hiperlipídica , Epitélio/efeitos dos fármacos , Epitélio/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Próstata/efeitos dos fármacos , Ratos , Receptores Androgênicos/metabolismo , Espaço Retroperitoneal/patologia
17.
Anal Bioanal Chem ; 413(16): 4161-4180, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34041576

RESUMO

Listeria monocytogenes is an invasive opportunistic foodborne pathogen and its routine surveillance is critical for protecting the food supply and public health. The traditional detection methods are time-consuming and require trained personnel. Lateral flow immunoassay (LFIA), on the other hand, is an easy-to-perform, rapid point-of-care test and has been widely used as an inexpensive surveillance tool. In recent times, nucleic acid-based lateral flow immunoassays (NALFIA) are also developed to improve sensitivity and specificity. A significant improvement in lateral flow-based assays has been reported in recent years, especially the ligands (antibodies, nucleic acids, aptamers, bacteriophage), labeling molecules, and overall assay configurations to improve detection sensitivity, specificity, and automated interpretation of results. In most commercial applications, LFIA has been used with enriched food/environmental samples to ensure detection of live cells thus prolonging the assay time to 24-48 h; however, with the recent improvement in LFIA sensitivity, results can be obtained in less than 8 h with shortened and improved enrichment practices. Incorporation of surface-enhanced Raman spectroscopy and/or immunomagnetic separation could significantly improve LFIA sensitivity for near-real-time point-of-care detection of L. monocytogenes for food safety and public health applications.


Assuntos
Imunoensaio/métodos , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , Animais , Anticorpos Imobilizados/química , Microbiologia de Alimentos , Humanos , Imunoensaio/instrumentação , Listeriose/diagnóstico , Ácidos Nucleicos/química , Sistemas Automatizados de Assistência Junto ao Leito
18.
Phys Chem Chem Phys ; 23(30): 16376-16389, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34318822

RESUMO

Cisplatin (cddp)-based chemotherapy is one of the most effective therapeutic alternatives for breast cancer treatment, the most common form of cancer, despite the severe side effects related to the high toxicity and low selectivity of cddp. To circumvent these drawbacks, the encapsulation of cddp into oxidized carbon nanohorns (CNHoxs) has been shown as a promising formulation with biocompatibility and low toxicity. However, there is still a lack of studies regarding the behavior of this cddp@CNHox nanovector on the cell membranes. This study presents an in silico description of the interactions between cddp@CNHox and membrane models of cancer (C_memb) and normal (N_memb) cells referring to a typical human breast. The results revealed the interaction mechanism of the inclusion complex 3cddp@CNHox (three cddp molecules are included in the CNHox cavity) with these biomembranes, which is a multistep process including approach, landing, insertion, and penetration. The 3cddp@CNHox stability was monitored over time, and demonstrated the trapping of cddp molecules inside the CNHox cavity over all simulations. The van der Waals contribution played a primary role (∼74%) for the complex stability. Moreover, the binding free energy calculations indicated that the interaction of the 3cddp@CNHox complex with the C_memb model was slightly more favorable, on average, than with the N_memb model. Analysis of the hydrogen bonds (HBs) formed over simulations of 800 ns explains the selectivity for the C_memb model, since the total number of HBs established between the inclusion complex and the C_memb model was about three times greater than that with the N_memb model. By reinforcing the potentiality of oxidized CNHox as a nanovector of cddp, the results presented in this study may assist and drive new experimental studies with this nanomaterial, focusing on the development of less aggressive formulations for breast cancer treatment.


Assuntos
Antineoplásicos/química , Materiais Biocompatíveis/química , Neoplasias da Mama/tratamento farmacológico , Carbono/química , Cisplatino/química , Nanocápsulas/química , Antineoplásicos/farmacologia , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Colesterol/química , Cisplatino/farmacologia , Composição de Medicamentos , Feminino , Humanos , Ligação de Hidrogênio , Bicamadas Lipídicas/química , Conformação Molecular , Simulação de Dinâmica Molecular , Fosfatidilcolinas/química
19.
Int J Mol Sci ; 22(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34445793

RESUMO

Spaceflight causes cardiovascular changes due to microgravity-induced redistribution of body fluids and musculoskeletal unloading. Cardiac deconditioning and atrophy on Earth are associated with altered Trp53 and oxidative stress-related pathways, but the effects of spaceflight on cardiac changes at the molecular level are less understood. We tested the hypothesis that spaceflight alters the expression of key genes related to stress response pathways, which may contribute to cardiovascular deconditioning during extended spaceflight. Mice were exposed to spaceflight for 15 days or maintained on Earth (ground control). Ventricle tissue was harvested starting ~3 h post-landing. We measured expression of select genes implicated in oxidative stress pathways and Trp53 signaling by quantitative PCR. Cardiac expression levels of 37 of 168 genes tested were altered after spaceflight. Spaceflight downregulated transcription factor, Nfe2l2 (Nrf2), upregulated Nox1 and downregulated Ptgs2, suggesting a persistent increase in oxidative stress-related target genes. Spaceflight also substantially upregulated Cdkn1a (p21) and cell cycle/apoptosis-related gene Myc, and downregulated the inflammatory response gene Tnf. There were no changes in apoptosis-related genes such as Trp53. Spaceflight altered the expression of genes regulating redox balance, cell cycle and senescence in cardiac tissue of mice. Thus, spaceflight may contribute to cardiac dysfunction due to oxidative stress.


Assuntos
Ciclo Celular/genética , Regulação da Expressão Gênica/genética , Genes cdc/genética , Coração/fisiologia , Estresse Oxidativo/genética , Animais , Apoptose/genética , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , Transdução de Sinais/genética , Voo Espacial/métodos , Ausência de Peso
20.
Molecules ; 26(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202844

RESUMO

The COVID-19 pandemic, as well as the more general global increase in viral diseases, has led researchers to look to the plant kingdom as a potential source for antiviral compounds. Since ancient times, herbal medicines have been extensively applied in the treatment and prevention of various infectious diseases in different traditional systems. The purpose of this review is to highlight the potential antiviral activity of plant compounds as effective and reliable agents against viral infections, especially by viruses from the coronavirus group. Various antiviral mechanisms shown by crude plant extracts and plant-derived bioactive compounds are discussed. The understanding of the action mechanisms of complex plant extract and isolated plant-derived compounds will help pave the way towards the combat of this life-threatening disease. Further, molecular docking studies, in silico analyses of extracted compounds, and future prospects are included. The in vitro production of antiviral chemical compounds from plants using molecular pharming is also considered. Notably, hairy root cultures represent a promising and sustainable way to obtain a range of biologically active compounds that may be applied in the development of novel antiviral agents.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Extratos Vegetais/farmacologia , Plantas Medicinais/química , SARS-CoV-2/efeitos dos fármacos , Antivirais/química , Antivirais/imunologia , Antivirais/uso terapêutico , Simulação por Computador , Humanos , Agricultura Molecular/métodos , Extratos Vegetais/química , Extratos Vegetais/imunologia , Extratos Vegetais/uso terapêutico , Plantas Medicinais/imunologia , SARS-CoV-2/fisiologia , Replicação Viral/efeitos dos fármacos
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