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1.
Gastroenterology ; 166(5): 886-901.e7, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38096955

RESUMO

BACKGROUND & AIMS: Metabolic and transcriptional programs respond to extracellular matrix-derived cues in complex environments, such as the tumor microenvironment. Here, we demonstrate how lysyl oxidase (LOX), a known factor in collagen crosslinking, contributes to the development and progression of cholangiocarcinoma (CCA). METHODS: Transcriptomes of 209 human CCA tumors, 143 surrounding tissues, and single-cell data from 30 patients were analyzed. The recombinant protein and a small molecule inhibitor of the LOX activity were used on primary patient-derived CCA cultures to establish the role of LOX in migration, proliferation, colony formation, metabolic fitness, and the LOX interactome. The oncogenic role of LOX was further investigated by RNAscope and in vivo using the AKT/NICD genetically engineered murine CCA model. RESULTS: We traced LOX expression to hepatic stellate cells and specifically hepatic stellate cell-derived inflammatory cancer-associated fibroblasts and found that cancer-associated fibroblast-driven LOX increases oxidative phosphorylation and metabolic fitness of CCA, and regulates mitochondrial function through transcription factor A, mitochondrial. Inhibiting LOX activity in vivo impedes CCA development and progression. Our work highlights that LOX alters tumor microenvironment-directed transcriptional reprogramming of CCA cells by facilitating the expression of the oxidative phosphorylation pathway and by increasing stemness and mobility. CONCLUSIONS: Increased LOX is driven by stromal inflammatory cancer-associated fibroblasts and correlates with diminished survival of patients with CCA. Modulating the LOX activity can serve as a novel tumor microenvironment-directed therapeutic strategy in bile duct pathologies.


Assuntos
Neoplasias dos Ductos Biliares , Fibroblastos Associados a Câncer , Colangiocarcinoma , Células Estreladas do Fígado , Proteína-Lisina 6-Oxidase , Microambiente Tumoral , Humanos , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/enzimologia , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Fibroblastos Associados a Câncer/enzimologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Colangiocarcinoma/patologia , Colangiocarcinoma/metabolismo , Colangiocarcinoma/genética , Colangiocarcinoma/enzimologia , Regulação Neoplásica da Expressão Gênica , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Células Estreladas do Fígado/enzimologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/enzimologia , Fosforilação Oxidativa , Proteína-Lisina 6-Oxidase/metabolismo , Proteína-Lisina 6-Oxidase/genética , Transdução de Sinais
2.
Bioinformatics ; 39(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36661327

RESUMO

SUMMARY: Here, we present sbml2hyb, an easy-to-use standalone Python tool that facilitates the conversion of existing mechanistic models of biological systems in Systems Biology Markup Language (SBML) into hybrid semiparametric models that combine mechanistic functions with machine learning (ML). The so-formed hybrid models can be trained and stored back in databases in SBML format. The tool supports a user-friendly export interface with an internal format validator. Two case studies illustrate the use of the sbml2hyb tool. Additionally, we describe HMOD, a new model format designed to support and facilitate hybrid models building. It aggregates the mechanistic model information with the ML information and follows as close as possible the SBML rules. We expect the sbml2hyb tool and HMOD to greatly facilitate the widespread usage of hybrid modeling techniques for biological systems analysis. AVAILABILITY AND IMPLEMENTATION: The Python interface, source code and the example models used for the case studies are accessible at: https://github.com/r-costa/sbml2hyb. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Linguagens de Programação , Biologia de Sistemas , Biologia de Sistemas/métodos , Modelos Biológicos , Software , Idioma
3.
Opt Lett ; 49(1): 53-56, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134150

RESUMO

This manuscript presents a wavelength-division multiplexing (WDM)-based photonic beamformer for an RF phased array antenna transmitter, capable of simultaneously generating multiple beams using the same optical spectrum. In the proposed architecture, for each RF beam, a WDM signal comprising the modulated RF sidebands undergoes complex-valued filtering, while another WDM signal with the same channels, but carrying only optical carriers, goes through an optical frequency-shifting stage. The proposed architecture allows the same WDM channels to be reused for multiple RF beams. The detection of the frequency-shifted optical carrier and the filtered RF sideband of each WDM channel at the photodetector produces a frequency-converted, correctly weighted signal to be fed to each antenna element. The features described herein are analytically derived, numerically simulated, and experimentally demonstrated. Results showcase two independent beams being transmitted in different directions.

4.
Biotechnol Bioeng ; 121(5): 1554-1568, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38343176

RESUMO

The combination of physical equations with deep learning is becoming a promising methodology for bioprocess digitalization. In this paper, we investigate for the first time the combination of long short-term memory (LSTM) networks with first principles equations in a hybrid workflow to describe human embryonic kidney 293 (HEK293) culture dynamics. Experimental data of 27 extracellular state variables in 20 fed-batch HEK293 cultures were collected in a parallel high throughput 250 mL cultivation system in an industrial process development setting. The adaptive moment estimation method with stochastic regularization and cross-validation were employed for deep learning. A total of 784 hybrid models with varying deep neural network architectures, depths, layers sizes and node activation functions were compared. In most scenarios, hybrid LSTM models outperformed classical hybrid Feedforward Neural Network (FFNN) models in terms of training and testing error. Hybrid LSTM models revealed to be less sensitive to data resampling than FFNN hybrid models. As disadvantages, Hybrid LSTM models are in general more complex (higher number of parameters) and have a higher computation cost than FFNN hybrid models. The hybrid model with the highest prediction accuracy consisted in a LSTM network with seven internal states connected in series with dynamic material balance equations. This hybrid model correctly predicted the dynamics of the 27 state variables (R2 = 0.93 in the test data set), including biomass, key substrates, amino acids and metabolic by-products for around 10 cultivation days.


Assuntos
Memória de Curto Prazo , Redes Neurais de Computação , Humanos , Células HEK293 , Rim
5.
Org Biomol Chem ; 22(11): 2252-2263, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38390694

RESUMO

Monitoring cell viability is critical in cell biology, pathology, and drug discovery. Most cell viability assays are cell-destructive, time-consuming, expensive, and/or hazardous. Herein, we present a series of newly synthesized 2,4,5-triaminopyrimidine derivatives able to discriminate between live and dead cells. To our knowledge, these compounds are the first fluorescent nucleobase analogues (FNAs) with cell viability monitoring potential. These new fluorescent molecules are synthesized using highly efficient and cost-effective methods and feature unprecedented photophysical properties (longer absorption and emission wavelengths, environment-sensitive emission, and unprecedented brightness within FNAs). Using a live-dead Saccharomyces cerevisiae cell and theoretical assays, the fluorescent 2,4,5-triaminopyrimidine derivatives were found to specifically accumulate inside dead cells by interacting with dsDNA grooves, thus paving the way for the emergence of novel and safe fluorescent cell viability markers emitting in the blue region. As the majority of commercially available viability dyes emit in the green to red region of the visible spectrum, these novel markers might be useful to meet the needs of blue markers for co-staining combinations.


Assuntos
Corantes Fluorescentes , Microscopia , Sobrevivência Celular
6.
Molecules ; 29(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38257384

RESUMO

In recent years, nutmeg (Myristica fragans Houtt.) has attracted considerable attention in the field of phytochemistry due to its diverse array of bioactive compounds. However, the potential application of nutmeg as a biorational for crop protection has been insufficiently explored. This study investigated the constituents of a nutmeg hydroethanolic extract via gas chromatography-mass spectrometry and vibrational spectroscopy. The research explored the extract's activity against phytopathogenic fungi and oomycetes, elucidating its mechanism of action. The phytochemical profile revealed fatty acids (including tetradecanoic acid, 9-octadecenoic acid, n-hexadecanoic acid, dodecanoic acid, and octadecanoic acid), methoxyeugenol, and elemicin as the main constituents. Previously unreported phytochemicals included veratone, gelsevirine, and montanine. Significant radial growth inhibition of mycelia was observed against Botrytis cinerea, Colletotrichum acutatum, Diplodia corticola, Phytophthora cinnamomi, and especially against Fusarium culmorum. Mode of action investigation, involving Saccharomyces cerevisiae labeled positively with propidium iodide, and a mutant strain affected in ERG6, encoding sterol C-24 methyltransferase, suggested that the extract induces a necrotic type of death and targets ergosterol biosynthesis. The evidence presented underscores the potential of nutmeg as a source of new antimicrobial agents, showing particular promise against F. culmorum.


Assuntos
Myristica , Saccharomyces cerevisiae , Proteção de Cultivos , Ergosterol , Extratos Vegetais
7.
Artigo em Inglês | MEDLINE | ID: mdl-38733327

RESUMO

This study aimed to evaluate heavy metals concentrations in soils and vegetables (cabbage, lettuce, and cassava) cultivated at Matola and Beluluane Industrial Parks, and to assess health risks linked to their consumption through estimated daily intake, hazard index (HI), and incremental lifetime cancer risk. Concentrations of Al, As, Co, Cd, Cr, Ni, Pb, and Zn were determined in the two sites. Soil concentrations of As at Beluluane site and As, Cd, and Cr at Matola site exceeded reference limits of the Food and Agriculture Organization/World Health Organization, showing heavy metal contamination. At Beluluane site, all studied vegetables presented As and Pb levels higher than reference limits, Cd concentrations were higher than the reference limit in cabbage, lettuce, and cassava leaves. At Matola site crops concentrations of As, Cd, Cr, and Pb exceeded the reference limits. Zinc exceeded the reference limit in all crops except in cabbage. HIs for vegetables from Beluluane exceeded 1.0 in cabbage (2.66), lettuce (2.27), and cassava leaves (2.37). Likewise, at Matola, HIs exceeded 1.0 in lettuce (1.67), cassava leaves (1.65), and root tubers (13). We found that vegetables cultivated in industrial parks present high carcinogenic risk due to heavy metal contamination, rendering them unsuitable for human consumption.


Assuntos
Contaminação de Alimentos , Metais Pesados , Poluentes do Solo , Metais Pesados/análise , Humanos , Poluentes do Solo/análise , Medição de Risco , Moçambique , Contaminação de Alimentos/análise , Verduras/química , Produtos Agrícolas/química , Monitoramento Ambiental
8.
J Hepatol ; 78(2): 364-375, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36848245

RESUMO

BACKGROUND & AIMS: Cholangiocarcinoma (CCA) is a heterogeneous and lethal malignancy, the molecular origins of which remain poorly understood. MicroRNAs (miRs) target diverse signalling pathways, functioning as potent epigenetic regulators of transcriptional output. We aimed to characterise miRNome dysregulation in CCA, including its impact on transcriptome homeostasis and cell behaviour. METHODS: Small RNA sequencing was performed on 119 resected CCAs, 63 surrounding liver tissues, and 22 normal livers. High-throughput miR mimic screens were performed in three primary human cholangiocyte cultures. Integration of patient transcriptomes and miRseq together with miR screening data identified an oncogenic miR for characterization. MiR-mRNA interactions were investigated by a luciferase assay. MiR-CRISPR knockout cells were generated and phenotypically characterized in vitro (proliferation, migration, colony, mitochondrial function, glycolysis) and in vivo using subcutaneous xenografts. RESULTS: In total, 13% (140/1,049) of detected miRs were differentially expressed between CCA and surrounding liver tissues, including 135 that were upregulated in tumours. CCA tissues were characterised by higher miRNome heterogeneity and miR biogenesis pathway expression. Unsupervised hierarchical clustering of tumour miRNomes identified three subgroups, including distal CCA-enriched and IDH1 mutant-enriched subgroups. High-throughput screening of miR mimics uncovered 71 miRs that consistently increased proliferation of three primary cholangiocyte models and were upregulated in CCA tissues regardless of anatomical location, among which only miR-27a-3p had consistently increased expression and activity in several cohorts. FoxO signalling was predominantly downregulated by miR-27a-3p in CCA, partially through targeting of FOXO1. MiR-27a knockout increased FOXO1 levels in vitro and in vivo, impeding tumour behaviour and growth. CONCLUSIONS: The miRNomes of CCA tissues are highly remodelled, impacting transcriptome homeostasis in part through regulation of transcription factors like FOXO1. MiR-27a-3p arises as an oncogenic vulnerability in CCA. IMPACT AND IMPLICATIONS: Cholangiocarcinogenesis entails extensive cellular reprogramming driven by genetic and non-genetic alterations, but the functional roles of these non-genetic events remain poorly understood. By unveiling global miRNA upregulation in patient tumours and their functional ability to increase proliferation of cholangiocytes, these small non-coding RNAs are implicated as critical non-genetic alterations promoting biliary tumour initiation. These findings identify possible mechanisms for transcriptome rewiring during transformation, with potential implications for patient stratification.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Proteína Forkhead Box O1 , MicroRNAs , Humanos , Neoplasias dos Ductos Biliares/genética , Ductos Biliares , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/genética , MicroRNAs/genética , Proteína Forkhead Box O1/metabolismo
9.
Anim Cogn ; 26(4): 1307-1318, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37184741

RESUMO

The alarm substance in fish is a pheromone released by injured individuals after a predator attack. When detected by other fish, it triggers fear/defensive responses, such as freezing and erratic movement behaviours. Such responses can also help other fish in the shoal to modulate their own behaviours: decreasing a fear response if conspecifics have not detected the alarm substance (social buffering) or triggering a fear response if conspecifics detected the alarm substance (social contagion). Response variation to these social phenomena is likely to depend on sex. Because males have higher-risk life-history strategies than females, they may respond more to social buffering where they risk not responding to a real predator attack, while females should respond more to social contagion because they only risk responding to a false alarm. Using zebrafish, we explored how the response of males and females to the presence/absence of the alarm substance is modified by the alarmed/unalarmed behaviour of an adjacent shoal of conspecifics. We found that, in social buffering, males decreased freezing more than females as expected, but in social contagion males also responded more than females by freezing at a higher intensity. Males were, therefore, more sensitive to visual information, while females responded more to the alarm substance itself. Because visual information updates faster than chemical information, males took more risks but potentially more benefits as well, because a quicker adjustment of a fear response allows to save energy to other activities. These sex differences provide insight into the modifying effect of life-history strategies on the use of social information.


Assuntos
Caracteres Sexuais , Peixe-Zebra , Animais , Feminino , Masculino , Peixe-Zebra/fisiologia , Comportamento Animal/fisiologia , Movimento , Feromônios/farmacologia
10.
Dig Dis Sci ; 68(7): 2811-2823, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36988759

RESUMO

Pancreatic cancer is one of the most fatal malignancies, as approximately 80% of patients are at advanced stages by the time of diagnosis. The main reason for the poor overall survival is late diagnosis that is partially due to the lack of tools for early-stage detection. In addition, there are several challenges in evaluating response to treatment and predicting prognosis. In this article, we do a review of the most common pancreatic cancer biomarkers with emphasis in new and promising approaches. Liquid biopsies seem to have important clinical applications in early detection, screening, prognosis, and longitudinal monitoring of on-treatment patients. Together with biomarkers in imaging, can represent valuable alternative non-invasive tools in order to achieve a more effective management of pancreatic cancer patients.


Assuntos
Biomarcadores Tumorais , Neoplasias Pancreáticas , Humanos , Biomarcadores Tumorais/genética , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/genética , Biópsia Líquida/métodos , Mutação , Neoplasias Pancreáticas
11.
Lett Appl Microbiol ; 76(4)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36928103

RESUMO

Actinomycetes produce secondary metabolites with many bioactivities such as antimicrobial, which can be useful as alternatives against resistant bacterial strains. Therefore, the screening of new habitats is likely to provide new strains with high potential. In this work, the antimicrobial capacity was used to select Streptomyces sp. strains isolated from Raf Raf forest (Tunisia). From the strain displaying higher activity, FR7, an ethyl acetate extract was prepared under optimized culturing conditions (10 days at 30°C in ISP2 medium with initial pH 8), showing significant antimicrobial activity against Micrococcus luteus and Staphylococcus aureus (MIC = 5 µg ml-1), and Listeria monocytogenes and Pseudomonas aeruginosa (MIC = 20 µg ml-1). The extract displayed strong DPPH radical scavenging activity (IC50 = 1.3 µg ml-1) and protection of yeast cells from H2O2-induced oxidative stress determined by flow cytometry with dichlorofluorescein diacetate. The crude extract showed the presence of polyketides, with methylsalicylic acid as moiety, a large and diverse group of secondary metabolites with a wide range of bioactivities, including antioxidant and antibacterial. Based on 16S RNA gene sequences, strain FR7 was identified as belonging to genus Streptomyces with high resemblance to S. iakyrus. Streptomyces sp. FR7 has great potential as a source of antibacterial and antioxidant metabolites.


Assuntos
Anti-Infecciosos , Streptomyces , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Solo , Streptomyces/metabolismo , Peróxido de Hidrogênio/metabolismo , Testes de Sensibilidade Microbiana , Antibacterianos/metabolismo , Anti-Infecciosos/metabolismo , Florestas
12.
Biotechnol Lett ; 45(10): 1293-1307, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37566297

RESUMO

Oilseed cakes (OC) are natural sources of lignocellulosic biomass, produced every year in large amounts. In addition to their main applications as animal feed, plant or soil fertilizer, and compost, they present enormous potential for being used in biotechnological processes for the obtainment and extraction of valuable bioactive compounds. This work evaluated the effect of solid-state fermentation on the bioactive properties of extracts obtained from the bioprocessing of OC and evaluated the effect of solvents on the recovery of compounds with higher bioactive potential. A general decrease of EC50 values was observed for fermented extracts obtained using a mixture of water/methanol (1:1) as extraction solvent. A decrease in the minimum inhibitory concentration was observed for fermented water extracts compared to non-fermented. Additionally, growth inhibition of Listeria monocytogenes was observed when using aqueous methanolic fermented extracts. These extracts also exhibited a higher percentage of growth reduction against phytopathogenic fungi, and some extracts exhibited increased protection against genotoxic agents such as camptothecin and bisphenol A. It was demonstrated that bioprocessing of OC through SSF is an effective approach to obtaining valuable compounds with bioactive properties for use in the food, pharmaceutical or cosmetic industries.


Assuntos
Antioxidantes , Extratos Vegetais , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Fermentação , Solventes , Água , Metanol
13.
Semin Cancer Biol ; 71: 42-51, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32679190

RESUMO

Colorectal cancer is highly incident worldwide and presents a health burden with elevated mortality rate despite prevention, detection, and treatment, mainly due to metastatic liver disease. Histological growth patterns of colorectal cancer liver metastases have emerged as a reproducible prognostic factor, with biological implications and therapeutic windows. Nonetheless, the histological growth patterns of colorectal cancer liver metastases are only known after pathological examination of a liver resection specimen, thus limiting the possibilities of pre-surgical decision. Predicting the histological growth pattern of colorectal cancer liver metastases would provide valuable information for patient-tailored medicine. In this article, we perform a review of the histological growth patterns and their implications, with a focus on the possibilities for their prediction.


Assuntos
Neoplasias Colorretais/patologia , Hepatectomia/métodos , Neoplasias Hepáticas/secundário , Animais , Neoplasias Colorretais/cirurgia , Humanos , Neoplasias Hepáticas/cirurgia
14.
J Neurosci ; 41(42): 8742-8760, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34470805

RESUMO

Hormones regulate behavior either through activational effects that facilitate the acute expression of specific behaviors or through organizational effects that shape the development of the nervous system thereby altering adult behavior. Much research has implicated the neuropeptide oxytocin (OXT) in acute modulation of various aspects of social behaviors across vertebrate species, and OXT signaling is associated with the developmental social deficits observed in autism spectrum disorders (ASDs); however, little is known about the role of OXT in the neurodevelopment of the social brain. We show that perturbation of OXT neurons during early zebrafish development led to a loss of dopaminergic neurons, associated with visual processing and reward, and blunted the neuronal response to social stimuli in the adult brain. Ultimately, adult fish whose OXT neurons were ablated in early life, displayed altered functional connectivity within social decision-making brain nuclei both in naive state and in response to social stimulus and became less social. We propose that OXT neurons have an organizational role, namely, to shape forebrain neuroarchitecture during development and to acquire an affiliative response toward conspecifics.SIGNIFICANCE STATEMENT Social behavior is developed over the lifetime of an organism and the neuropeptide oxytocin (OXT) modulates social behaviors across vertebrate species, and is associated with neuro-developmental social deficits such as autism. However, whether OXT plays a role in the developmental maturation of neural systems that are necessary for social behavior remains poorly explored. We show that proper behavioral and neural response to social stimuli depends on a developmental process orchestrated by OXT neurons. Animals whose OXT system is ablated in early life show blunted neuronal and behavioral responses to social stimuli as well as wide ranging disruptions in the functional connectivity of the social brain. We provide a window into the mechanisms underlying OXT-dependent developmental processes that implement adult sociality.


Assuntos
Neurônios/metabolismo , Ocitocina/antagonistas & inibidores , Ocitocina/metabolismo , Comportamento Social , Animais , Animais Geneticamente Modificados , Feminino , Masculino , Metronidazol/toxicidade , Neurônios/efeitos dos fármacos , Ocitocina/genética , Receptores de Ocitocina/antagonistas & inibidores , Receptores de Ocitocina/genética , Receptores de Ocitocina/metabolismo , Peixe-Zebra
15.
Br J Cancer ; 127(6): 988-1013, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35650276

RESUMO

The first consensus guidelines for scoring the histopathological growth patterns (HGPs) of liver metastases were established in 2017. Since then, numerous studies have applied these guidelines, have further substantiated the potential clinical value of the HGPs in patients with liver metastases from various tumour types and are starting to shed light on the biology of the distinct HGPs. In the present guidelines, we give an overview of these studies, discuss novel strategies for predicting the HGPs of liver metastases, such as deep-learning algorithms for whole-slide histopathology images and medical imaging, and highlight liver metastasis animal models that exhibit features of the different HGPs. Based on a pooled analysis of large cohorts of patients with liver-metastatic colorectal cancer, we propose a new cut-off to categorise patients according to the HGPs. An up-to-date standard method for HGP assessment within liver metastases is also presented with the aim of incorporating HGPs into the decision-making processes surrounding the treatment of patients with liver-metastatic cancer. Finally, we propose hypotheses on the cellular and molecular mechanisms that drive the biology of the different HGPs, opening some exciting preclinical and clinical research perspectives.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/patologia
16.
Small ; 18(49): e2203999, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36316233

RESUMO

Lung metastases represent the most adverse clinical factor and rank as the leading cause of osteosarcoma-related death. Nearly 80% of patients present lung micrometastasis at diagnosis not detected with current clinical tools. Herein, an exosome (EX)-based imaging tool is developed for lung micrometastasis by positron emission tomography (PET) using osteosarcoma-derived EXs as natural nanocarriers of the positron-emitter copper-64 (64 Cu). Exosomes are isolated from metastatic osteosarcoma cells and functionalized with the macrocyclic chelator NODAGA for complexation with 64 Cu. Surface functionalization has no effect on the physicochemical properties of EXs, or affinity for donor cells and endows them with favorable pharmacokinetics for in vivo studies. Whole-body PET/magnetic resonance imaging (MRI) images in xenografted models show a specific accumulation of 64 Cu-NODAGA-EXs in metastatic lesions as small as 2-3 mm or in a primary tumor, demonstrating the exquisite tropism of EXs for homotypic donor cells. The targetability for lung metastasis is also observed by optical imaging using indocyanine green (ICG)-labeled EXs and D-luciferin-loaded EXs. These findings show that tumor-derived EXs hold great potential as targeted imaging agents for the noninvasive detection of small lung metastasis by PET. This represents a step forward in the biomedical application of EXs in imaging diagnosis with increased translational potential.


Assuntos
Neoplasias Pulmonares , Tomografia por Emissão de Pósitrons , Humanos , Neoplasias Pulmonares/diagnóstico por imagem
17.
Biol Lett ; 18(12): 20220232, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36541092

RESUMO

Optimistic and pessimistic cognitive biases have been described in many animals and are related to the perceived valence of the environment. We, therefore, hypothesize that such cognitive bias can be adaptive depending on environmental conditions. In reward-rich environments, an optimistic bias would be favoured, whereas in harsh environments, a pessimistic one would thrive. Here, we empirically investigated the potential adaptive value of such bias using zebrafish as a model. We first phenotyped female zebrafish in an optimistic/pessimistic axis using a previously validated judgement bias assay. Optimistic and pessimistic females were then exposed to an unpredictable chronic stress protocol for 17 days, after which fish were euthanized and the sectional area of the different ovarian structures was quantified in both undisturbed and stressed groups. Our results show that zebrafish ovarian development responded to chronic stress, and that judgement bias impacted the relative area of the vitellogenic developmental stage, with pessimists showing higher vitellogenic areas as compared with optimists. These results suggest that pessimism maximizes reproductive investment, through increased vitellogenesis, indicating a relationship between cognitive bias and life-history organismal decisions.


Assuntos
Pessimismo , Peixe-Zebra , Animais , Feminino , Pessimismo/psicologia , Julgamento , Cognição , Viés
18.
J Appl Microbiol ; 132(4): 2733-2745, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35092131

RESUMO

AIMS: Assess the antibacterial and antioxidant effects of ethanol extracts of Portuguese propolis samples when combined with gentamicin, a widely used aminoglycoside antibiotic, or with honey, collected from the same apiary as propolis. METHODS AND RESULTS: Using the agar dilution method and DPPH free radical scavenging assay, antimicrobial and antioxidant synergistic effects between propolis and gentamicin or honey were assessed. Synergism between propolis and gentamicin was observed for all the tested extracts and against all the indicator bacteria, with particular interest against the Methicillin-Resistant Staphylococcus aureus (MRSA) with a threefold decrease of the gentamicin MIC if mixed with 25 µg ml-1 propolis. Likely to propolis and gentamicin, mixtures of sub-MIC concentrations of propolis and honey enhanced the antibacterial action of each individual natural product against the majority of the strains. However, propolis antioxidant capacity decreased along with higher honey content in the mixture. CONCLUSIONS: Propolis has a strong synergistic effect when combined with gentamicin, allowing the reduction of the therapeutic dose of this drug. Propolis and honey mixtures also display a stronger antibacterial effect than the activity exhibited by each sample when tested individually, whereas the high antioxidant capacity of propolis seems to be not affected when in combination with honey. SIGNIFICANCE AND IMPACT OF STUDY: When mixed with honey, propolis antioxidant potential is maintained, or just slightly reduced up to 1:1 dilution, and show synergistic antibacterial effects, allowing to optimize the use of this usually scarce natural resource. Also, considering the antibiotic resistance problem, natural beehive products, alone or in the mixture, are promising alternatives to retard the outbreak of microbial resistance.


Assuntos
Mel , Staphylococcus aureus Resistente à Meticilina , Própole , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Gentamicinas/farmacologia , Testes de Sensibilidade Microbiana , Própole/química , Própole/farmacologia , Staphylococcus aureus
19.
Bioprocess Biosyst Eng ; 45(11): 1889-1904, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36245012

RESUMO

Flux balance analysis (FBA) is currently the standard method to compute metabolic fluxes in genome-scale networks. Several FBA extensions employing diverse objective functions and/or constraints have been published. Here we propose a hybrid semi-parametric FBA extension that combines mechanistic-level constraints (parametric) with empirical constraints (non-parametric) in the same linear program. A CHO dataset with 27 measured exchange fluxes obtained from 21 reactor experiments served to evaluate the method. The mechanistic constraints were deduced from a reduced CHO-K1 genome-scale network with 686 metabolites, 788 reactions and 210 degrees of freedom. The non-parametric constraints were obtained by principal component analysis of the flux dataset. The two types of constraints were integrated in the same linear program showing comparable computational cost to standard FBA. The hybrid FBA is shown to significantly improve the specific growth rate prediction under different constraints scenarios. A metabolically efficient cell growth feed targeting minimal byproducts accumulation was designed by hybrid FBA. It is concluded that integrating parametric and nonparametric constraints in the same linear program may be an efficient approach to reduce the solution space and to improve the predictive power of FBA methods when critical mechanistic information is missing.


Assuntos
Redes e Vias Metabólicas , Modelos Biológicos , Cricetinae , Animais , Cricetulus , Células CHO
20.
Molecules ; 27(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36364353

RESUMO

Propolis, a natural product made by bees with resins and balsams, is known for its complex chemical composition and remarkable bioactivities. In this study, propolis extraction was studied seeking extracts with strong bioactivities using less orthodox solvents, with some derived from apiary products. For that, a propolis sample collected from Gerês apiary in 2018 (G18) was extracted by maceration with six different solvents: absolute ethanol, ethanol/water (7:3), honey brandy, mead, propylene glycol and water. The solvent influence on the chemical composition and antioxidant and antimicrobial activities of the extracts was investigated. Antioxidant potential was assessed by the DPPH free-radical-scavenging assay and the antimicrobial activity by the agar dilution method. Chemical composition of the extracts was determined in vitro by three colorimetric assays: total ortho-diphenols, phenolics and flavonoids contents and the LC-MS technique. To our knowledge, this is the first time that solvents such as honey brandy and mead have been studied. Honey brandy showed considerable potential to extract propolis active compounds able to inhibit the growth of bacteria such as the methicillin-sensitive Staphylococcus aureus and Propionibacterium acnes (MIC values of 100 and 200 µg/mL, respectively) and the fungi Candida albicans and Saccharomyces cerevisiae (MIC = 500 µg/mL, for both). Mead extracts displayed high antioxidant capacity (EC50 = 1.63 ± 0.27 µg/mL) and great activity against resistant bacteria such as the methicillin-resistant Staphylococcus aureus and Escherichia coli (MIC = 750 µg/mL, for both). The production of such solvents made from beehive products further promotes a diversification of apiary products and the exploration of new applications using eco-friendly solutions.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Própole , Própole/farmacologia , Própole/química , Solventes , Antioxidantes/farmacologia , Antioxidantes/química , Testes de Sensibilidade Microbiana , Candida albicans , Etanol/química , Escherichia coli , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Água
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