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1.
Int J Biol Macromol ; 266(Pt 1): 131055, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38522681

RESUMO

The B-MYB gene encodes a transcription factor (B-MYB) that regulates cell growth and survival. Abnormal expression of B-MYB is frequently observed in lung cancer and poses challenges for targeted drug therapy. Oncogenes often contain DNA structures called G-quadruplexes (G4s) in their promoter regions, and B-MYB is no exception. These G4s play roles in genetic regulation and are potential cancer treatment targets. In this study, a probe was designed to specifically identify a G4 within the promoter region of the B-MYB gene. This probe combines an acridine derivative ligand with a DNA segment complementary to the target sequence, enabling it to hybridize with the adjacent sequence of the G4 being investigated. Biophysical studies demonstrated that the acridine derivative ligands C5NH2 and C8NH2 not only effectively stabilized the G4 structure but also exhibited moderate affinity. They were capable of altering the G4 topology and exhibited enhanced fluorescence emission in the presence of this quadruplex. Additionally, these ligands increased the number of G4s observed in cellular studies. Through various biophysical studies, the target sequence was shown to form a G4 structure, even with an extra nucleotide tail added to its flanking region. Cellular studies confirmed the co-localization between the target sequence and the developed probe.

2.
Chemistry ; 30(22): e202400285, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38386665

RESUMO

The main goal of this work was to elucidate the potential relevance of (radio)metal chelates of 99mTc and Re targeting G-quadruplex structures for the design of new tools for cancer theranostics. 99mTc provides the complexes with the ability to perform single-photon-emission computed tomography imaging studies, while the Re complexes should act as anticancer agents upon interaction with specific G4 DNA or RNA structures present in tumor tissues. Towards this goal, we have developed isostructural 99mTc(I) and Re(I) tricarbonyl complexes anchored by a pyrazolyl-diamine (Pz) chelator carrying a pendant pyridostatin (PDS) fragment as the G4-binding motif. The interaction of the PDF-Pz-Re (8) complex with different G4-forming oligonucleotides was studied by circular dichroism, fluorescence spectroscopy and FRET-melting assays. The results showed that the Re complex retained the ability to bind and stabilize G4-structures from different DNA or RNA sequences, namely those present on the SRC proto-oncogene and telomeric RNA (TERRA sequence). PDF-Pz-Re (8) showed low to moderate cytotoxicity in PC3 and MCF-7 cancer cell lines, as typically observed for G4-binders. Biodistribution studies of the congener PDF-Pz-99mTc (12) in normal mice showed that the complex undergoes a fast blood clearance with a predominant hepatobiliary excretion, pointing also for a high in vitro stability.


Assuntos
Aminoquinolinas , Quadruplex G , Neoplasias , Ácidos Picolínicos , Rênio , Camundongos , Animais , Tecnécio/química , Distribuição Tecidual , DNA/química , Quelantes/química , Tomografia Computadorizada de Emissão de Fóton Único , RNA , Rênio/química , Compostos Radiofarmacêuticos/química
3.
Biomed Phys Eng Express ; 10(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38417163

RESUMO

Radiometric surveys in radiotherapy bunkers have been carried out in Brazil for many years, both by the same radiotherapy facility for verification of shielding as by the regulatory agency for licensing and control purposes. In recent years, the Intensity Modulated Radiation Therapy (IMRT) technique has been gradually incorporated into many facilities. Therefore, it has been necessary to consider the increased leakage component that has an important impact on the secondary walls. For that, a radiometric survey method has been used that considers an increased 'time of beam-on' for the secondary walls. In this work we discuss two methods of doing this: the first considers that this 'time of beam-on' affects the sum of the two components, leakage and scattered. In another method it is considered that only the leakage component is affected by this extended 'time of beam-on'. We compare the methods and show that for secondary walls withU= 1 the first method overestimates dose rates by important percentages and for secondary walls withU< 1 it can both overestimate or underestimate the dose rates, depending on the parameters of the project. An optimized procedure is proposed, according to the use factor (U) of the secondary wall to be measured.


Assuntos
Proteção Radiológica , Radioterapia de Intensidade Modulada , Proteção Radiológica/métodos , Radiometria/métodos , Radioterapia de Intensidade Modulada/métodos , Planejamento da Radioterapia Assistida por Computador/métodos
4.
Funct Plant Biol ; 512024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163648

RESUMO

Environments originating from banded iron formations, such as the canga , are important reference ecosystems for the recovery of degraded areas by mining. The objective of this work was to evaluate if the relationship between morphofunctional and photosynthetic attributes of native canga species from different functional group results in distinct responses when grown in iron mining tailings substrate. The experiment was carried out with species belonging to different functional groups: a widespread semi-deciduous tree-shrub, Myrcia splendens ; an endemic deciduous shrub, Jacaranda caroba ; and a nitrogen-fixing herbaceous species, Periandra mediterranea . The species were grown in two conditions, reference soil and iron ore tailing. Despite belonging to different functional groups when grown in tailings, the morphofunctional attributes presented similar responses between species. M. splendens was the species most affected by the conditions imposed by the iron ore mining tailings, with decreased light-use efficiency and electron transport. P. mediterranea had satisfactory growth and maintenance of photosynthetic attributes. J. caroba growing in the tailings increased the effective quantum yield of PSII. The photochemical and growth assessments were able to better explain the adaptive strategies developed by the species, guaranteeing a greater chance of success during the rehabilitation of mining substrates.


Assuntos
Ecossistema , Ferro , Plantas/metabolismo , Árvores/metabolismo , Mineração
5.
Evid Based Dent ; 25(1): 49-50, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38273113

RESUMO

DATA SOURCES: Medline via EBSCOhost, PubMed, and Scopus up to February 2023. STUDY SELECTION: Observational studies in the English language published in peer-reviewed journals, encompassing children aged 0 to 6 years exposed to environmental tobacco smoke and passive smoking, with a focus on oral health conditions in deciduous dentition. DATA EXTRACTION AND SYNTHESIS: Data were extracted from 25 papers, encompassing study details, oral health, and smoking exposure. Confounding factors such as parental education, income, diet, fluoride exposure, gender, and oral hygiene practices were also identified. The risk of bias was assessed using the Newcastle-Ottawa Scale (NOS). Frequency effect size was calculated for health variables and smoking exposure. RESULTS: Most studies identified a correlation between passive smoking and an increased prevalence of dental caries. Environmental tobacco smoke exposure and dental caries risk were influenced by factors such as low parental education, socioeconomic status, dietary habits, oral hygiene, and gender. CONCLUSIONS: The results of this systematic review strongly indicate a significant association between dental caries in deciduous dentition and passive smoking.


Assuntos
Cárie Dentária , Poluição por Fumaça de Tabaco , Criança , Adulto , Pré-Escolar , Humanos , Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Saúde Bucal , Poluição por Fumaça de Tabaco/efeitos adversos , Suscetibilidade à Cárie Dentária , Dieta
6.
Int J Biol Macromol ; 259(Pt 2): 129157, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199539

RESUMO

Oral cancer incidence and mortality are increasing over time. The most common therapies for oral cancers are surgery and radiotherapy, either used alone or combined, and immunotherapy can be also an option. Although there are several therapeutic options, none of them are completely effective, and in addition, there are numerous associated side effects. To overcome these limitations, researchers have been trying to reduce these drawbacks by using drug delivery systems that carry drugs for specific delivery to cancer cells. For that purpose, RNA-coated liposomes to selectively deliver the ligands C8 (acridine orange derivative) and dexamethasone to oral cancer cells were produced, characterized, and biologically evaluated. Firstly, the RNA structure and binding interaction with ligands (C8 and dexamethasone) were evaluated by circular dichroism (CD), thermal difference spectroscopy (TDS), nuclear magnetic resonance (NMR) and fluorescence titrations. The biophysical assays evidenced the formation of an RNA hairpin and duplex structure. Moreover, steady-state and time-resolved fluorescence intensity and anisotropy experiments show that C8 forms a complex with RNA and adopts an open conformation upon RNA binding. Then, RNA-coated liposomes were characterized by dynamic light scattering, and diameters near 160 nm were observed. Time-resolved anisotropy measurements of C8 loaded in RNA-functionalized liposomes indicate the co-existence of free C8 in solution (inside the liposome) and C8 bound to RNA at the external liposome surface. The RNA-functionalized liposomes loaded with C8 or dexamethasone mediated a significant reduction in the cell viability of malignant UPCI-SCC-154 cells while maintaining viable non-malignant NHDF cells. Additionally, the liposomes were able to internalize the cells, with higher uptake by the malignant cell line. Overall, the results obtained in this work can contribute to the development of new drug delivery systems based on RNA-coated liposomes.


Assuntos
Lipossomos , Neoplasias Bucais , Humanos , Lipossomos/química , Sistemas de Liberação de Medicamentos , Linhagem Celular , Neoplasias Bucais/tratamento farmacológico , Dexametasona/farmacologia
7.
Braz Oral Res ; 38: e013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38198311

RESUMO

This study aimed to develop and validate a self-administered questionnaire in Brazilian Portuguese to verify the level of knowledge of orthodontists in the care of pregnant, lactating, and postmenopausal women, named "Considerations on Orthodontic Treatment during Pregnancy, Lactation, and Postmenopausal Periods." The development and validation of the questionnaire consisted of the following steps: a) item generation; b) item reduction; c) questionnaire design; and d) validity and reliability tests in a cross-sectional study with 258 orthodontists working in the field from different Brazilian states. A total of 60 orthodontists participated in test-retest over a mean period of 45 days. The preliminary questionnaire consisted of a total of 60 questions. After item reduction, 40 questions were selected for the final version of the questionnaire, with eight questions about pregnant women; six about lactating women; 18 about postmenopausal women, and eight about general knowledge in dentistry. Each item had three response options in the Likert scale format. Face and content validity analysis, reliability assessment through internal consistency (Cronbach's alpha and McDonald's omega), and test-retest reliability through the intraclass correlation coefficient (ICC) and Spearman's correlation coefficient were performed. Face and content validity indicated that the questionnaire was considered valid, objective, and easily understandable. The questionnaire had good internal consistency (Cronbach's alpha = 0.77; McDonald's omega = 0.78) and good test-retest reliability (ICC = 0.71; Spearman's correlation coefficient = 0.51). The questionnaire was considered valid and reliable to assess the level of knowledge of orthodontists in the care of pregnant, lactating, and postmenopausal women.


Assuntos
Lactação , Pós-Menopausa , Gravidez , Feminino , Humanos , Estudos Transversais , Reprodutibilidade dos Testes , Aleitamento Materno
8.
Biomed Phys Eng Express ; 10(2)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38237176

RESUMO

To enhance the effect of radiation on the tumor without increasing the dose to the patient, the combination of high-Z nanoparticles with radiotherapy has been proposed. In this work, we investigate the effects of the physical parameters of nanoparticles (NPs) on the Dose Enhancement Factor (DEF), and on the Sensitive Enhancement Ratio (SER) by applying a version of the Linear Quadratic Model. A method for constructing voxelized realistic cell geometries in Monte Carlo simulations from confocal microscopy images was developed and applied to Gliobastoma Multiforme cell lines (U87 and U373). The comparison of simulations with realistic geometry and spherical geometry shows that there is significant impact on the survival curves obtained for the same irradiation conditions. Using this model, the DEF and the SER are determined as a function of the concentration, size and distribution of gold nanoparticles within the cell. For small NPs,dAuNP= 10 nm, no clear trend in the DEF and SER was observed when the number of NPs within the cell increases. Experimentally, the variable number of NPs measured inside the U373 cells (ranging between 1.48 × 105and 1.19 × 106) also did not influence much the observed cell survival upon irradiation of the cells with a Co-60 source. The same lack of trend is obtained when the Au content in the cell is kept constant, 0.897 mg/g, but the size of the NPs is changed. However, if the number of NPs is kept constant (7.91 × 105) and the size changes, there is a critical diameter above which the dose effect increases significantly. Using the realistic geometries, it was verified that the key parameter for the DEF and the SER enhancement is the volume fraction of Au in the cell, with NP size being a more important parameter than the number of NPs.


Assuntos
Nanopartículas Metálicas , Humanos , Dosagem Radioterapêutica , Ouro , Microscopia , Simulação por Computador
9.
Mol Pharm ; 21(1): 216-233, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37992229

RESUMO

Nuclear DNA is the canonical target for biological damage induced by Auger electrons (AE) in the context of targeted radionuclide therapy (TRT) of cancer, but other subcellular components might also be relevant for this purpose, such as the energized mitochondria of tumor cells. Having this in mind, we have synthesized novel DOTA-based chelators carrying a prostate-specific membrane antigen (PSMA) inhibitor and a triphenyl phosphonium (TPP) group that were used to obtain dual-targeted 111In-radioconjugates ([111In]In-TPP-DOTAGA-PSMA and [111In]In-TPP-DOTAGA-G3-PSMA), aiming to promote a selective uptake of an AE-emitter radiometal (111In) by PSMA+ prostate cancer (PCa) cells and an enhanced accumulation in the mitochondria. These dual-targeted 111In-radiocomplexes are highly stable under physiological conditions and in cell culture media. The complexes showed relatively similar binding affinities toward the PSMA compared to the reference tracer [111In]In-PSMA-617, in line with their high cellular uptake and internalization in PSMA+ PCa cells. The complexes compromised cell survival in a dose-dependent manner and in the case of [111In]In-TPP-DOTAGA-G3-PSMA to a higher extent than observed for the single-targeted congener [111In]In-PSMA-617. µSPECT imaging studies in PSMA+ PCa xenografts showed that the TPP pharmacophore did not interfere with the excellent in vivo tumor uptake of the "golden standard" [111In]In-PSMA-617, although it led to a higher kidney retention. Such kidney retention does not necessarily compromise their usefulness as radiotherapeutics due to the short tissue range of the Auger/conversion electrons emitted by 111In. Overall, our results provide valuable insights into the potential use of mitochondrial targeting by PSMA-based radiocomplexes for efficient use of AE-emitting radionuclides in TRT, giving impetus to extend the studies to other AE-emitting trivalent radiometals (e.g., 161Tb or 165Er) and to further optimize the designed dual-targeting constructs.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/metabolismo , Glutamato Carboxipeptidase II/metabolismo , Antígenos de Superfície/metabolismo , Radioisótopos , Compostos Radiofarmacêuticos , Mitocôndrias/metabolismo , Linhagem Celular Tumoral
10.
Int J Biol Macromol ; 254(Pt 2): 127715, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918599

RESUMO

Polysaccharides in plant-exuded gums are complex biopolymers consisting of a wide range of structural variability (linkages, monosaccharide composition, substituents, conformation, chain length and branching). The structural features of polysaccharides confer the ability to be exploited in different industrial sectors and applications involving biological systems. Moreover, these characteristics are attributed to a direct relationship in the process of polysaccharide enzymatic degradation by the fermentative action in the gut microbiota, through intrinsic interactions connecting bacterial metabolism and the production of various metabolites that are associated with regulatory effects on the host homeostasis system. Molecular docking analysis between bacterial target proteins and arabinogalactan-type polysaccharide obtained from gum arabic allowed the identification of intermolecular interactions provided bacterial enzymatic mechanism for the degradation of several arabinogalactan monosaccharide chains, as a model for the study and prediction of potential fermentable polysaccharide. This review discusses the main structural characteristics of polysaccharides from exudate gums of plants and their interactions with the intestinal microbiota.


Assuntos
Microbioma Gastrointestinal , Prebióticos , Simulação de Acoplamento Molecular , Polissacarídeos/química , Gomas Vegetais/química , Plantas/metabolismo , Monossacarídeos
11.
Caries Res ; 58(2): 108-114, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38104541

RESUMO

BACKGROUND: Developmental defects of enamel (DDE) are a result of disturbances during formation and maturation of the enamel. Evaluating the most-cited DDE papers can provide important tools that point to the gaps and strengths of this important topic in dentistry. SUMMARY: This bibliometric study analyzed the 100 most-cited papers on DDE. Using a combined keyword search strategy, the 100 most-cited papers were selected in the Web of Science Core Collection. Papers that addressed any type of DDE were included. The extracted data were title, number of citations, study theme, authorship, journal, type of DDE, type of dentition (primary or permanent), type of diagnosis, study design, year, and country of publication. The bibliometric networks were generated through VOSviewer software. The 100 papers had a range from 78 to 459 citations. The main themes of studies were etiopathogenesis (53%), prevalence and incidence (22%), and diagnosis (8%). The authors with the highest number of citations were Goodman AH and Rose JC (459 citations). Most articles were published in dental journals (47%). The most studied types of DDE were fluorosis and amelogenesis imperfecta in the permanent dentition (47%). Observational (24%) and non-systematic reviews (24%) were the most common study designs and ranged from 1977 to 2019. The country with the highest number of publications was the USA (41%). KEY MESSAGES: Most of the top 100 DDE papers were about fluorosis and amelogenesis imperfecta, with top papers from three continents with English as the native language. This topic is of great importance in dentistry, and the need for further studies is highlighted, especially regarding the diagnosis and treatment of some DDEs.


Assuntos
Amelogênese Imperfeita , Humanos , Bibliometria , Projetos de Pesquisa
12.
Braz. oral res. (Online) ; 38: e013, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1528146

RESUMO

Abstract This study aimed to develop and validate a self-administered questionnaire in Brazilian Portuguese to verify the level of knowledge of orthodontists in the care of pregnant, lactating, and postmenopausal women, named "Considerations on Orthodontic Treatment during Pregnancy, Lactation, and Postmenopausal Periods." The development and validation of the questionnaire consisted of the following steps: a) item generation; b) item reduction; c) questionnaire design; and d) validity and reliability tests in a cross-sectional study with 258 orthodontists working in the field from different Brazilian states. A total of 60 orthodontists participated in test-retest over a mean period of 45 days. The preliminary questionnaire consisted of a total of 60 questions. After item reduction, 40 questions were selected for the final version of the questionnaire, with eight questions about pregnant women; six about lactating women; 18 about postmenopausal women, and eight about general knowledge in dentistry. Each item had three response options in the Likert scale format. Face and content validity analysis, reliability assessment through internal consistency (Cronbach's alpha and McDonald's omega), and test-retest reliability through the intraclass correlation coefficient (ICC) and Spearman's correlation coefficient were performed. Face and content validity indicated that the questionnaire was considered valid, objective, and easily understandable. The questionnaire had good internal consistency (Cronbach's alpha = 0.77; McDonald's omega = 0.78) and good test-retest reliability (ICC = 0.71; Spearman's correlation coefficient = 0.51). The questionnaire was considered valid and reliable to assess the level of knowledge of orthodontists in the care of pregnant, lactating, and postmenopausal women.

13.
Chemistry ; : e202303591, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038361

RESUMO

Due to their favorable chemical features, Re and Tc complexes have been widely used for the development of new therapeutic agents and imaging probes to solve problems of biomedical relevance. This review provides an update of the most relevant research efforts towards the development of novel cancer theranostic agents using Re and Tc-based compounds interacting with specific DNA structures. This includes a variety of homometallic complexes, namely those containing M(CO)3 (M=Re, Tc) moieties, that exhibit different modes of interaction with DNA, such as covalent binding, intercalation, groove binding or G-quadruplex DNA binding. Additionally, heterometallic complexes, designed to potentiate synergistic effects of different metal centers to improve DNA-targeting, cytotoxicity and fluorescence properties, are also reviewed. Particular attention is also given to 99m Tc- and 188 Re-labeled oligonucleotides that have been widely explored to develop imaging and therapeutic radiopharmaceuticals through the in vivo hybridization with a specific complementary DNA or RNA target sequence to provide useful molecular tools in precision medicine for cancer diagnosis and treatment. Finally, the need for further improvement of DNA-targeted Re and Tc-based compounds as potential therapeutic and diagnostic agents is highlighted, and future directions are discussed.

14.
Braz Dent J ; 34(6): 100-109, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38133084

RESUMO

This study aimed to analyze the 100 most-cited papers in Dentistry, with a focus on female leadership in dental research. Papers were retrieved from the Web of Science Core Collection (WoS- CC) in the category 'Dentistry, Oral Surgery & Medicine'. Gender was assessed through WoS-CC, Scopus, ResearchGate, social media, institutional websites, and software that assigns gender according to first names (https://genderapi.io). Characteristics of authors in leadership roles were retrieved, such as affiliation, publication history, citations, H factor, and i500. The 100 most-cited papers in Dentistry were authored by 394 researchers, 326 (82.7%) men, and 68 (17.3%) women - there were 4.8 male authors for each female. Among the lead authors, there were 11.3 males for each female. Among female senior authors, there were 7 males for each female. Among lead/senior authors of the 100 most-cited papers (first and last authors, respectively), 18 were women. There was an increase in the participation of women in the top cited papers regardless of authorship role across the six decades, with a peak of two female authors in the first decade of the 21st century. For female authors in leadership roles, their publication history shows the time between their first and last papers in WoS-CC ranged from 4 to 42 years for lead authors and 1 to 39 years for senior authors. Women were found to be largely underrepresented as leaders of the 100 most-cited papers, highlighting pervasive gender inequalities in dental research publications.


Assuntos
Pesquisa em Odontologia , Cirurgia Bucal , Humanos , Masculino , Feminino , Liderança , Bibliometria , Autoria
15.
Nature ; 623(7988): 757-764, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37968390

RESUMO

Extreme weather events perturb ecosystems and increasingly threaten biodiversity1. Ecologists emphasize the need to forecast and mitigate the impacts of these events, which requires knowledge of how risk is distributed among species and environments. However, the scale and unpredictability of extreme events complicate risk assessment1-4-especially for large animals (megafauna), which are ecologically important and disproportionately threatened but are wide-ranging and difficult to monitor5. Traits such as body size, dispersal ability and habitat affiliation are hypothesized to determine the vulnerability of animals to natural hazards1,6,7. Yet it has rarely been possible to test these hypotheses or, more generally, to link the short-term and long-term ecological effects of weather-related disturbance8,9. Here we show how large herbivores and carnivores in Mozambique responded to Intense Tropical Cyclone Idai, the deadliest storm on record in Africa, across scales ranging from individual decisions in the hours after landfall to changes in community composition nearly 2 years later. Animals responded behaviourally to rising floodwaters by moving upslope and shifting their diets. Body size and habitat association independently predicted population-level impacts: five of the smallest and most lowland-affiliated herbivore species declined by an average of 28% in the 20 months after landfall, while four of the largest and most upland-affiliated species increased by an average of 26%. We attribute the sensitivity of small-bodied species to their limited mobility and physiological constraints, which restricted their ability to avoid the flood and endure subsequent reductions in the quantity and quality of food. Our results identify general traits that govern animal responses to severe weather, which may help to inform wildlife conservation in a volatile climate.


Assuntos
Tamanho Corporal , Tempestades Ciclônicas , Mamíferos , Animais , Altitude , Biodiversidade , Carnivoridade , Conservação dos Recursos Naturais , Dieta/veterinária , Ecossistema , Clima Extremo , Inundações , Previsões , Herbivoria , Mamíferos/anatomia & histologia , Mamíferos/fisiologia , Moçambique
16.
Sensors (Basel) ; 23(22)2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-38005657

RESUMO

The field of organic-borne biomarkers has been gaining relevance due to its suitability for diagnosing pathologies and health conditions in a rapid, accurate, non-invasive, painless and low-cost way. Due to the lack of analytical techniques with features capable of analysing such a complex matrix as the human breath, the academic community has focused on developing electronic noses based on arrays of gas sensors. These sensors are assembled considering the excitability, sensitivity and sensing capacities of a specific nanocomposite, graphene. In this way, graphene-based sensors can be employed for a vast range of applications that vary from environmental to medical applications. This review work aims to gather the most relevant published papers under the scope of "Graphene sensors" and "Biomarkers" in order to assess the state of the art in the field of graphene sensors for the purposes of biomarker identification. During the bibliographic search, a total of six pathologies were identified as the focus of the work. They were lung cancer, gastric cancer, chronic kidney diseases, respiratory diseases that involve inflammatory processes of the airways, like asthma and chronic obstructive pulmonary disease, sleep apnoea and diabetes. The achieved results, current development of the sensing sensors, and main limitations or challenges of the field of graphene sensors are discussed throughout the paper, as well as the features of the experiments addressed.


Assuntos
Asma , Grafite , Neoplasias Pulmonares , Doença Pulmonar Obstrutiva Crônica , Humanos , Asma/diagnóstico , Biomarcadores , Testes Respiratórios/métodos
17.
Pharmaceuticals (Basel) ; 16(10)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37895872

RESUMO

Ascidians are marine invertebrates that synthesize sulfated glycosaminoglycans (GAGs) within their viscera. Ascidian GAGs are considered analogues of mammalian GAGs and possess great potential as bioactive compounds, presenting antitumoral and anticoagulant activity. Due to its worldwide occurrence and, therefore, being a suitable organism for large-scale mariculture in many marine environments, our main objectives are to study Microcosmus exasperatus GAGs regarding composition, structure, and biological activity. We also aim to develop efficient protocols for sulfated polysaccharides extraction and purification for large-scale production and clinical applications. GAGs derived from M. exasperatus viscera were extracted by proteolytic digestion, purified by ion-exchange liquid chromatography, and characterized by agarose gel electrophoresis and enzymatic treatments. Anticoagulant activity was evaluated by APTT assays. Antitumoral activity was assessed in an in vitro model of tumor cell culture using MTT, clonogenic, and wound healing assays, respectively. Our results show that M. exasperatus presents three distinct polysaccharides; among them, two were identified: a dermatan sulfate and a fucosylated dermatan sulfate. Antitumoral activity was confirmed for the total polysaccharides (TP). While short-term incubation does not affect tumor cell viability at low concentrations, long-term TP incubation decreases LLC tumor cell growth/proliferation at different concentrations. In addition, TP decreased tumor cell migration at different concentrations. In conclusion, we state that M. exasperatus presents great potential as an alternative GAG source, producing compounds with antitumoral properties at low concentrations that do not possess anticoagulant activity and do not enhance other aspects of malignancy, such as tumor cell migration. Our perspectives are to apply these molecules in future preclinical studies for cancer treatment as antitumoral agents to be combined with current treatments to potentiate therapeutic efficacy.

18.
Dalton Trans ; 52(43): 15757-15766, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37846621

RESUMO

The pursuit of molecular imaging for tumors has led to endeavors focused on targeting epidermal growth factor receptors (EGFR) through monoclonal antibodies or radionuclide-labelled EGF analogs with 99mTc, 111In, or 131I. In this context, various 99mTc-labeled EGFR inhibitors using quinazoline structures have been reported based on the so-called pendant approach and on two types of complexes and labelling strategies: "4 + 1" mixed ligand complexes and fac-tricarbonyl complexes. Apart from this approach, which alters lead structures by linking pharmacophores to chelator frameworks through different connectors, the integrated incorporation of topoisomerase and tyrosine kinase inhibitors into Re and 99mTc complexes has not been explored. Here we present [M(η6-inhibitor)2]+ (M = Re, 99mTc) and [Re(η6-bz)(η6-inhibitor)]+ complexes, where the core structure of an EGFR tyrosine kinase inhibitor binds directly to the metal center. These complexes exhibit potential for tumor imaging: initial biological investigations highlight the influence of one versus two bound inhibitors on the metal center.


Assuntos
Radioisótopos , Rênio , Radioisótopos/química , Receptores ErbB/metabolismo , Quelantes/química , Diagnóstico por Imagem , Rênio/química , Tecnécio/química , Compostos Radiofarmacêuticos/química
19.
J Endod ; 49(12): 1595-1604, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37690496

RESUMO

INTRODUCTION: Knowledge of bibliometric indices on the avulsion of permanent teeth can help researchers to identify gaps in the literature. The aim of this study was to analyze the bibliometric characteristics of the 100 most-cited articles on the avulsion of permanent teeth. MATERIALS AND METHODS: Two researchers conducted an unfiltered search in the Core Collection section of the Web of Science (WoS-CC) database. The following data were extracted: position in the citation list, total number and density of citations, title, authors, institution, country, year of publication, journal, keywords, study design, tooth storage medium, and other topics of interest. Bibliometric networks were generated and analyzed using the VOSviewer software. Descriptive analysis and a Poisson regression analysis were performed (P < .05). RESULTS: The number of citations per article varied between 31 and 407. The average was 70.05, and 13 articles received more than 100 citations. J.O. Andreasen (n = 13) and M. Trope (n = 15) were the authors who contributed most often to publications. The United States was the country with the highest number of articles (n = 31). Authors associated with the University of Copenhagen, Denmark (n = 9) and University of North Carolina, USA (n = 10) showed higher productivity. In vitro/animal model studies were the most frequent study designs (n = 50), and the most-discussed topic of interest was prognosis (n = 47). There was strong clustering among 13 research groups. CONCLUSION: Observational studies, published by authors from Europe and about prognosis or treatment presented more citation ratio in WoS-CC. Clinical studies on permanent tooth avulsion are needed to increase the quality of scientific evidence and provide insights for health professionals and public policy makers.


Assuntos
Bibliometria , Projetos de Pesquisa , Estados Unidos , Prognóstico , Bases de Dados Factuais
20.
Front Plant Sci ; 14: 1214112, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37636086

RESUMO

An ever-growing collection of commercial biostimulants is becoming available in a wide variety of forms and compositions to improve crop performance. Given the intricate nature of deciphering the underlying mechanisms of commercial products, which typically comprise various biological components, it is crucial for research in this area to have robust tools to demonstrate their effectiveness in field trials. Here, we took a multi-attribute approach to evaluating the impact of biostimulants on crop performance. First, we assessed the impact of a biostimulant on the soil and rhizosphere microbiomes associated to crops in eight reference farms, including corn (3 farms), soybean (2), cotton (2) and sugarcane (1), in different biomes and production contexts in Brazil and Paraguay. Second, we modeled a set of integrated indicators to measure crop responses to biostimulant application, including five analytical themes as follows: i) crop development and production (9 indicators), ii) soil chemistry (9), iii) soil physics (5), iv) soil biology (6) and v) plant health (10). Amplicon 16S rRNA and ITS sequencing revealed that the use of the biostimulant consistently changes the structure of bacterial and fungal communities associated with the production system for all evaluated crops. In the rhizosphere samples, the most responsive bacterial taxa to biostimulant application were Prevotella in cotton; Prauserella and Methylovirgula in corn; and Methylocapsa in sugar cane. The most responsive fungal taxa to biostimulant use were Arachnomyces in soybean and cotton; and Rhizophlyctis in corn. The proposed integrated indicators yielded highly favorable positive impact indices (averaging at 0.80), indicating that biostimulant-treated fields correlate with better plant development and crop performance. Prominent indices were observed for indicators in four themes: soil biology (average index 0.84), crop production (0.81), soil physics (compaction reduction 0.81), and chemical fertility (0.75). The multi-attribute approach employed in this study offers an effective strategy for assessing the efficacy of biostimulant products across a wide range of crops and production systems.

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