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1.
Braz Oral Res ; 38: e080, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39258633

RESUMO

This bibliometric study aimed to identify and analyze the 100 most cited articles about orofacial trauma in children and adolescents. The search was conducted in the Web of Science Core Collection (WoS-CC) using a combined search strategy. Two researchers collected the following data from each article: year of publication, country, journal, number and density of citations, author, institutions, study design, type of trauma, and keywords. The VOSviewer and SPSS version 22.0 softwares were used for data analyses. The articles were published from 1968 to 2012 and the number of citations ranged from 49 to 176. Europe was the continent with most articles (40 articles; 3,408 citations). Brazil was the country that made the largest contribution (20 articles; 1,741 citations) and the Universidade do Sul de Santa Catarina (Brazil) was the institution with most articles (5 articles; 492 citations). Marcenes W was the most productive author (8 articles; 968 citations). The cross-sectional study design was the most common (50 articles; 3,978 citations). The most frequent field was epidemiology (73 articles; 5,971 citations). The most widely used criteria for trauma diagnosis were the Andreasen (18 articles; 1,505 citations) and Le Fort (3 articles; 260 citations). Strong positive correlations were found in the number of citations between WoS-CC and Google Scholar (r = 0.929; p < 0.001), WoS-CC and Scopus (r = 0.976; p < 0.001), and Google Scholar and Scopus (r = 0.903; p < 0.001). The 100 most cited articles about orofacial trauma in children and adolescents were mainly cross-sectional studies published by Brazilian authors in epidemiology using Andreasen criteria. Dental Traumatology was the journal with the largest contribution.


Assuntos
Bibliometria , Publicações Periódicas como Assunto , Humanos , Criança , Adolescente , Publicações Periódicas como Assunto/estatística & dados numéricos , Traumatismos Faciais/epidemiologia , Brasil/epidemiologia
2.
ChemMedChem ; : e202400438, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39302068

RESUMO

We herein describe the radiosynthesis of a 125I-labeled acridine orange derivative ([125I]-C8), acting as a G-quadruplex binder, and its biological evaluation in cervical cancer models, aiming to enlighten its potential as a radioligand for Auger Electron Radiopharmaceutical Therapy (AE-RPT) of cancer. [125I]-C8 was synthesized with a moderate radiochemical yield (ca. 60 %) by a [125I]iodo-destannylation reaction. Its evaluation in cervical cancer HeLa cells demonstrated that the radiocompound has a significant cellular internalization with a notorious accumulation in the cell nucleus. In line with these results, [125I]-C8 strongly compromised the viability of HeLa cells in a dose-dependent manner, inducing non-repairable DNA lesions that are most probably due to the AEs emitted by 125I in close proximity to  the DNA. Biodistribution studies in a murine HeLa xenograft model showed that [125I]-C8 has fast blood clearance and high in vivo stability but poor tumor uptake, after systemic administration. The respective supramolecular conjugate with the AS1411 aptamer ([125I]-C8/AS1411) led to a slower blood clearance in the same animal tumor model, although without improving the tumor uptake. To take advantage of the radiotoxicity of [125I]-C8 against cervical cancer cells other strategies need to be studied, based namely on alternative nanodelivery carriers and/or intratumoral injection approaches.

3.
Evid Based Dent ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227698

RESUMO

DESIGN: Cohort study. DATA ANALYSIS: Confirmatory Factor Analysis (CFA) and Structured Equation Modeling (SEM). RESULTS: Psychosocial status emerged as the main predictor of traumatic dental injuries (TDIs). Better psychosocial status had a direct protective effect on the incidence of TDIs. The impact of increased overjet and lower parental schooling on TDIs was mediated through psychosocial status. Children residing in areas with poorer contextual socio-economic indicators faced a higher risk of experiencing new TDIs due to psychosocial factors. CONCLUSIONS: Poor psychosocial status directly correlated to TDIs. Indirectly, psychosocial factors mediated the occurrence of TDIs through overjet, parental schooling and contextual residential area.

4.
Malar J ; 23(1): 234, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103843

RESUMO

BACKGROUND: More than 95% of malaria transmission in Brazil occurs in the Legal Amazon Region, which in 2010 recorded around 333,429 cases reported in the Epidemiological Surveillance Information System-Malaria (Sivep_malaria), presenting an annual parasitic incidence (IPA) of 13.1 cases/1000 inhabitants. METHODS: This was a descriptive study that measured the community prevalence of Plasmodium infection and its relationship with land use in Três Fronteiras District, Colniza Municipality, Mato Grosso State. Data were collected during household visits in July 2011, with blood collection from finger pricks for the preparation of thick smear slides, and completion of a standardized case notification form. A georeferenced database was analysed, with land use evaluated as categorical variables. A kernel density map was built to show the density of cases and their location. RESULTS: Of the 621 respondents, 68(11%) had Plasmodium infection: 39 (57.4%) with Plasmodium vivax, 27(39.7%) with Plasmodium falciparum and two (2.9%) with mixed infections. Among infected individuals, 49 (72.1%) were men. Cases of malaria were distributed over the district, with greater occurrence of cases per household in open areas close to the mining company and artisanal mining sites. The was a greater density of cases located in the gold mining region. CONCLUSION: Transmission of malaria in Três Fronteiras District has a heterogeneous distribution. Individuals residing in mining and timber extraction sites have increased occurrence of Plasmodium infection.


Assuntos
Malária Falciparum , Malária Vivax , População Rural , Brasil/epidemiologia , Humanos , Feminino , Masculino , Adolescente , Adulto , População Rural/estatística & dados numéricos , Pessoa de Meia-Idade , Adulto Jovem , Criança , Pré-Escolar , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Prevalência , Lactente , Idoso , Incidência , Idoso de 80 Anos ou mais , Plasmodium vivax , Malária/epidemiologia , Malária/transmissão
5.
J Oral Implantol ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158854

RESUMO

Guided bone regeneration involving the use of titanium mesh and platelet-rich fibrin could be a feasible approach in cases of severely atrophic ridges. The purpose of this case report was to present an esthetic and functional rehabilitation in the anterior maxilla with the installation of dental implants in conjunction with guided bone regeneration using titanium mesh and advanced platelet-rich fibrin (A-PRF). A 60-year-old patient presented bone atrophy and partial edentulism in the anterior maxilla. After clinical and cone beam computed tomography assessment, guided bone regeneration was planned using a titanium mesh and A-PRF with xenograft bone. After eight months of healing, the dental implants were placed with the aid of a surgical guide to obtain accurate three-dimensional positioning. Prosthetic rehabilitation was carried out with individualized crowns. After two years of follow-up, radiographic analysis demonstrated a good quality and density of the bone tissue adjacent to the dental implants. No radiolucent areas were observed, and there were no clinical signs of failure. In cases of severe atrophy, using a titanium mesh and A-PRF proved to be a feasible alternative for bone reconstruction prior to dental implant placement. This approach can aid dental professionals in achieving an ideal implant positioning for rehabilitation with individualized crowns.

6.
Int J Surg Case Rep ; 122: 110100, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39098173

RESUMO

INTRODUCTION: Glomus tumor is a pericytic mesenchymal neoplasm that most commonly occurs in the extremities. The occurrence in visceral organs is rare and is a differential diagnosis with other gastric submucosal tumors. PRESENTATION OF CASE: A woman with epigastric pain underwent esophagogastroduodenoscopy (EGD) which revealed a gastric submucosal tumor. Endoscopic ultrasound with fine-needle aspiration allowed preoperative diagnosis of gastric glomus tumor. Intraoperative EGD-assisted laparoscopic segmental gastrectomy was successfully performed. The patient was discharged in the second postoperative day. There was no evidence of recurrence at 8 months of follow-up. DISCUSSION: The stomach is a rare location for the glomus tumor, a neoplasm of the glomus body, which is a perivascular structure with thermoregulatory function. Preoperative diagnosis is challenging, and endoscopic ultrasound (EUS) is useful for both assessing malignancy-associated features and biopsy guiding. The treatment is surgical resection with attention to adequate oncological margins while preserving healthy gastric wall. CONCLUSION: Immunohistochemical analysis of specimen obtained by EUS fine-needle allows accurate preoperative diagnosis and laparoscopic-endoscopic combined surgery allows good oncological and functional results.

7.
Pharmaceutics ; 16(7)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39065597

RESUMO

The present work consisted of an exploratory study aiming to evaluate in vitro the potential of AuNPs during Radiation Therapy (RT) in human pancreatic adenocarcinoma cells. AuNPs coated with hyaluronic and oleic acids (HAOA-AuNPs) or with bombesin peptides (BBN-AuNPs) were used. AuNPs were characterized by Atomic Force Microscopy (AFM) and Dynamic Light Scattering. BxPC-3 tumor cells were irradiated with a 6 MV X-rays beam, in the absence or presence of AuNPs. AFM showed that HAOA-AuNPs and BBN-AuNPs are spherical with a mean size of 83 ± 20 nm and 49 ± 12 nm, respectively. For RT alone, a reduction in cell viability of up to 33 ± 12% was obtained compared to the control (p ≤ 0.0001). HAOA-AuNPs alone at 200 and 400 µM showed a reduction in cell viability of 20 ± 4% and 35 ± 4%, respectively, while for BBN-AuNPs, at 50 and 200 µM, a reduction in cell viability of 25 ± 3% and 37 ± 3% was obtained, respectively, compared to the control (p < 0.0001). At 72 h post-irradiation, a decrease in cell viability of 26 ± 3% and 22 ± 2% between RT + HAOA-AuNPs at 400 µM and RT + BBN-AuNPs at 50 µM, compared to RT alone, was obtained (p < 0.004). The combination of RT with AuNPs led to a significant decrease in cell viability compared to the control, or RT alone, thus representing an improved effect.

8.
Chem Commun (Camb) ; 60(61): 7874-7877, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38819786

RESUMO

A folic acid-targeted polyurea (PURE) dendrimer was easily radiolabelled with Technetium-99m (99mTc-PUREG4-FA2) avoiding the use of additional ligands and bioconjugation chemistry. This straightforward strategy is enabled in PURE dendrimers due to their favourable surface terminal groups configuration, showing coordination capabilities and turning these biodendrimers into attractive platforms for nanoradiotheranostics.


Assuntos
Dendrímeros , Neoplasias Ovarianas , Tecnécio , Dendrímeros/química , Humanos , Feminino , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/tratamento farmacológico , Tecnécio/química , Nanomedicina Teranóstica , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/síntese química , Compostos de Organotecnécio/química , Ligantes , Polímeros/química , Ácido Fólico/química
9.
Int J Biol Macromol ; 266(Pt 1): 131055, 2024 May.
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.


Assuntos
Proteínas de Ciclo Celular , Corantes Fluorescentes , Quadruplex G , Humanos , Corantes Fluorescentes/química , Regiões Promotoras Genéticas , Proto-Oncogene Mas , Ligantes , Transativadores/genética , Transativadores/metabolismo , Transativadores/química , Acridinas/química , Acridinas/farmacologia
10.
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
11.
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
12.
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
13.
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
14.
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 , Saúde Bucal , Poluição por Fumaça de Tabaco , Humanos , Poluição por Fumaça de Tabaco/efeitos adversos , Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Pré-Escolar , Criança , Lactente , Dente Decíduo , Masculino , Feminino , Prevalência , Higiene Bucal , Fatores de Risco
15.
Funct Plant Biol ; 512024 01.
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
16.
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
17.
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
18.
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
19.
Chemistry ; 30(13): e202303591, 2024 Mar 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.


Assuntos
Neoplasias , Rênio , Humanos , Tecnécio/química , Compostos Radiofarmacêuticos/química , Diagnóstico por Imagem , DNA , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Rênio/química
20.
Caries Res ; 58(2): 104-110, 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
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