Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Molecules ; 29(10)2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38792144

RESUMO

Peripheral nerve injuries (PNI) impact millions of individuals in the United States, prompting thousands of nerve repair procedures annually. Nerve conduits (NC) are commonly utilized to treat nerve injuries under 3 cm but larger gaps still pose a challenge for successful peripheral nerve regeneration (PNR) and functional recovery. This is partly attributed to the absence of bioactive agents such as stem cells or growth factors in FDA-approved conduits due to safety, harvesting, and reproducibility concerns. Therefore, curcumin, a bioactive phytochemical, has emerged as a promising alternative bioactive agent due to its ability to enhance PNR and overcome said challenges. However, its hydrophobicity and rapid degradation in aqueous solutions are considerable limitations. In this work, a nanoscale delivery platform with tannic acid (TA) and polyvinylpyrrolidone (PVP) was developed to encapsulate curcumin for increased colloidal and chemical stability. The curcumin nanoparticles (CurNPs) demonstrate significantly improved stability in water, reduced degradation rates, and controlled release kinetics when compared to free curcumin. Further, cell studies show that the CurNP is biocompatible when introduced to neuronal cells (SH-SY5Y), rat Schwann cells (RSC-S16), and murine macrophages (J774 A.1) at 5 µM, 5 µM, and 10 µM of curcumin, respectively. As a result of these improved physicochemical properties, confocal fluorescence microscopy revealed superior delivery of curcumin into these cells when in the form of CurNPs compared to its free form. A hydrogen peroxide-based oxidative stress study also demonstrated the CurNP's potential to protect J774 A.1 cells against excessive oxidative stress. Overall, this study provides evidence for the suitability of CurNPs to be used as a bioactive agent in NC applications.


Assuntos
Curcumina , Nanopartículas , Curcumina/farmacologia , Curcumina/química , Animais , Ratos , Nanopartículas/química , Camundongos , Humanos , Sistemas de Liberação de Medicamentos , Regeneração Nervosa/efeitos dos fármacos , Polímeros/química , Células de Schwann/efeitos dos fármacos , Liberação Controlada de Fármacos , Taninos/química , Taninos/farmacologia , Linhagem Celular , Estresse Oxidativo/efeitos dos fármacos , Povidona/química
2.
Int Wound J ; 21(10): e70047, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39376068

RESUMO

Surgical success includes a planned incision, achieving haemostasis, good mechanical closure and optimal maintenance of the surgical wound. New materials, as tissue adhesives, have been suggested as substitutes for sutures, to overcome their disadvantages. This study aimed at gathering the differences of using surgical adhesives in oral surgery compared with the conventional method of using sutures as a wound closure technique. PRISMA analyses, PICO criteria and PubMed/Medline database, EBSCO and Cochrane Library were used for research. Inclusion criteria included prospective, randomized controlled trials and case-control studies published in English with full access, where clinical advantages and demerits/limitations were reported in patients who underwent oral surgical incisions, without time restrictions. Exclusion criteria comprised literature with lower level of evidence. A total of 15 studies were assessed and analysed 15 parameters as alternatives to sutures (100%), cost-effectiveness (6,6%), postoperative pain (53,3%), time consumption (73,3%), haemostasis (46,6%), homeostasis (13,3%), aids healing (26,6%), tissue inflammation (26,6%), safety (6,6%), graft dimension (3,13), biocompatibility (13,3%), adhesion to tissue (6,6%), bacteriostatic effect (20%), oedema (13,3%) and ease of application (26,6). Selected articles' results indicate that surgical glues can be a suitable alternative and/or adjuvant to oral sutures, presenting numerous advantages.


Assuntos
Adesivos Teciduais , Técnicas de Fechamento de Ferimentos , Cicatrização , Humanos , Procedimentos Cirúrgicos Bucais/métodos , Ferida Cirúrgica/cirurgia , Adesivos Teciduais/uso terapêutico
3.
Hum Mol Genet ; 29(8): 1253-1273, 2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32129442

RESUMO

Some mutations affecting dynamin 2 (DNM2) can cause dominantly inherited Charcot-Marie-Tooth (CMT) neuropathy. Here, we describe the analysis of mice carrying the DNM2 K562E mutation which has been associated with dominant-intermediate CMT type B (CMTDIB). Contrary to our expectations, heterozygous DNM2 K562E mutant mice did not develop definitive signs of an axonal or demyelinating neuropathy. Rather, we found a primary myopathy-like phenotype in these mice. A likely interpretation of these results is that the lack of a neuropathy in this mouse model has allowed the unmasking of a primary myopathy due to the DNM2 K562E mutation which might be overshadowed by the neuropathy in humans. Consequently, we hypothesize that a primary myopathy may also contribute to the disease mechanism in some CMTDIB patients. We propose that these findings should be considered in the evaluation of patients, the determination of the underlying disease processes and the development of tailored potential treatment strategies.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Dinamina II/deficiência , Doenças Musculares/genética , Miopatias Congênitas Estruturais/genética , Animais , Axônios/metabolismo , Axônios/patologia , Doença de Charcot-Marie-Tooth/patologia , Dinamina II/genética , Heterozigoto , Humanos , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Doenças Musculares/patologia , Mutação/genética , Miopatias Congênitas Estruturais/patologia , Fenótipo
4.
Molecules ; 25(13)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32646009

RESUMO

Fostered by the advances in the instrumental and analytical fields, in recent years the analysis of volatile organic compounds (VOCs) has emerged as a new frontier in medical diagnostics. VOCs analysis is a non-invasive, rapid and inexpensive strategy with promising potential in clinical diagnostic procedures. Since cellular metabolism is altered by diseases, the resulting metabolic effects on VOCs may serve as biomarkers for any given pathophysiologic condition. Human VOCs are released from biomatrices such as saliva, urine, skin emanations and exhaled breath and are derived from many metabolic pathways. In this review, the potential of VOCs present in saliva will be explored as a monitoring tool for several oral diseases, including gingivitis and periodontal disease, dental caries, and oral cancer. Moreover, the analytical state-of-the-art for salivary volatomics, e.g., the most common extraction techniques along with the current challenges and future perspectives will be addressed unequivocally.


Assuntos
Biomarcadores Tumorais/metabolismo , Cárie Dentária/metabolismo , Neoplasias Bucais/metabolismo , Doenças Periodontais/metabolismo , Saliva/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Humanos
5.
PLoS Biol ; 13(9): e1002258, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26406915

RESUMO

The pathogenesis of peripheral neuropathies in adults is linked to maintenance mechanisms that are not well understood. Here, we elucidate a novel critical maintenance mechanism for Schwann cell (SC)-axon interaction. Using mouse genetics, ablation of the transcriptional regulators histone deacetylases 1 and 2 (HDAC1/2) in adult SCs severely affected paranodal and nodal integrity and led to demyelination/remyelination. Expression levels of the HDAC1/2 target gene myelin protein zero (P0) were reduced by half, accompanied by altered localization and stability of neurofascin (NFasc)155, NFasc186, and loss of Caspr and septate-like junctions. We identify P0 as a novel binding partner of NFasc155 and NFasc186, both in vivo and by in vitro adhesion assay. Furthermore, we demonstrate that HDAC1/2-dependent P0 expression is crucial for the maintenance of paranodal/nodal integrity and axonal function through interaction of P0 with neurofascins. In addition, we show that the latter mechanism is impaired by some P0 mutations that lead to late onset Charcot-Marie-Tooth disease.


Assuntos
Moléculas de Adesão Celular/metabolismo , Doença de Charcot-Marie-Tooth/genética , Proteína P0 da Mielina/genética , Bainha de Mielina/fisiologia , Fatores de Crescimento Neural/metabolismo , Animais , Moléculas de Adesão Celular Neuronais/metabolismo , Doença de Charcot-Marie-Tooth/enzimologia , Técnicas de Inativação de Genes , Histona Desacetilase 1/metabolismo , Histona Desacetilase 2/metabolismo , Humanos , Camundongos
6.
Anal Bioanal Chem ; 410(18): 4459-4468, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29732495

RESUMO

Saliva is possibly the easiest biofluid to analyse and, despite its simple composition, contains relevant metabolic information. In this work, we explored the potential of the volatile composition of saliva samples as biosignatures for breast cancer (BC) non-invasive diagnosis. To achieve this, 106 saliva samples of BC patients and controls in two distinct geographic regions in Portugal and India were extracted and analysed using optimised headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME/GC-MS, 2 mL acidified saliva containing 10% NaCl, stirred (800 rpm) for 45 min at 38 °C and using the CAR/PDMS SPME fibre) followed by multivariate statistical analysis (MVSA). Over 120 volatiles from distinct chemical classes, with significant variations among the groups, were identified. MVSA retrieved a limited number of volatiles, viz. 3-methyl-pentanoic acid, 4-methyl-pentanoic acid, phenol and p-tert-butyl-phenol (Portuguese samples) and acetic, propanoic, benzoic acids, 1,2-decanediol, 2-decanone, and decanal (Indian samples), statistically relevant for the discrimination of BC patients in the populations analysed. This work defines an experimental layout, HS-SPME/GC-MS followed by MVSA, suitable to characterise volatile fingerprints for saliva as putative biosignatures for BC non-invasive diagnosis. Here, it was applied to BC samples from geographically distant populations and good disease separation was obtained. Further studies using larger cohorts are therefore very pertinent to challenge and strengthen this proof-of-concept study. Graphical abstract ᅟ.


Assuntos
Neoplasias da Mama/diagnóstico , Saliva/química , Compostos Orgânicos Voláteis/análise , Adolescente , Adulto , Neoplasias da Mama/etnologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Geografia , Humanos , Concentração de Íons de Hidrogênio , Índia , Metabolômica , Pessoa de Meia-Idade , Concentração Osmolar , Portugal , Estudo de Prova de Conceito , Microextração em Fase Sólida , Temperatura , Adulto Jovem
7.
J Mater Sci Mater Med ; 28(5): 65, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28321800

RESUMO

The aim of this in vitro study was to evaluate the removal torque values on abutments and the morphological wear aspects of two different dental implant joints after immersion in a medium containing biofilm from human saliva. Twenty implant-abutment assemblies were divided into four groups in this study: (A) Morse taper free of medium containing biofilm, and (B) after contact with a medium containing biofilm from human saliva; (C) External Hexagon free of medium containing biofilm, and (D) after contact with medium containing biofilm from human saliva. The abutments were firstly torqued to the implants according to the manufacturer´s recommendations, using a handheld torque meter. Groups B and D were immersed into 24 well-plates containing 2 ml BHI medium with microorganisms for 72 h at 37 °C under microaerophilic conditions. After detorque evaluation, the abutments were removed and the implants were analyzed by scanning electron microscopy (SEM) and profilometry. On the detorque evaluation, the torque values decreased for the external hexagon implants and increased for the Morse taper implants. However, the values were lower when both implant-abutment assemblies were in contact with a medium containing biofilm from human saliva. The wear areas of contacting surfaces of the implants were identified by SEM. The highest average roughness values were recorded on the surfaces free of biofilm. The medium containing biofilm from human saliva affected the maintenance of the torque values on Morse taper and external hexagon abutments. Additionally, the removal of abutment altered the inner implant surfaces resulting in an increase of wear of the titanium-based connection.


Assuntos
Dente Suporte , Implantes Dentários , Falha de Restauração Dentária , Biofilmes/crescimento & desenvolvimento , Projeto do Implante Dentário-Pivô , Análise do Estresse Dentário , Humanos , Técnicas In Vitro , Teste de Materiais , Microscopia Eletrônica de Varredura , Saliva/microbiologia , Propriedades de Superfície , Titânio , Torque
8.
Hum Mol Genet ; 22(21): 4417-29, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23813975

RESUMO

The ubiquitously expressed large GTPase Dynamin 2 (DNM2) plays a critical role in the regulation of intracellular membrane trafficking through its crucial function in membrane fission, particularly in endocytosis. Autosomal-dominant mutations in DNM2 cause tissue-specific human disorders. Different sets of DNM2 mutations are linked to dominant intermediate Charcot-Marie-Tooth neuropathy type B, a motor and sensory neuropathy affecting primarily peripheral nerves, or autosomal-dominant centronuclear myopathy (CNM) presenting with primary damage in skeletal muscles. To understand the underlying disease mechanisms, it is imperative to determine to which degree the primary affected cell types require DNM2. Thus, we used cell type-specific gene ablation to examine the consequences of DNM2 loss in skeletal muscle cells, the major relevant cell type involved in CNM. We found that DNM2 function in skeletal muscle is required for proper mouse development. Skeletal muscle-specific loss of DNM2 causes a reduction in muscle mass and in the numbers of muscle fibers, altered muscle fiber size distributions, irregular neuromuscular junctions (NMJs) and isolated degenerating intramuscular peripheral nerve fibers. Intriguingly, a lack of muscle-expressed DNM2 triggers an increase of lipid droplets (LDs) and mitochondrial defects. We conclude that loss of DNM2 function in skeletal muscles initiates a chain of harmful parallel and serial events, involving dysregulation of LDs and mitochondrial defects within altered muscle fibers, defective NMJs and peripheral nerve degeneration. These findings provide the essential basis for further studies on DNM2 function and malfunction in skeletal muscles in health and disease, potentially including metabolic diseases such as diabetes.


Assuntos
Doença de Charcot-Marie-Tooth/fisiopatologia , Dinamina II/deficiência , Dinamina II/fisiologia , Metabolismo dos Lipídeos , Mitocôndrias/metabolismo , Músculo Esquelético/fisiologia , Miopatias Congênitas Estruturais/fisiopatologia , Junção Neuromuscular/fisiologia , Nervos Periféricos/fisiologia , Animais , Doença de Charcot-Marie-Tooth/genética , Dinamina II/genética , Dinamina II/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Mutação , Miopatias Congênitas Estruturais/genética , Junção Neuromuscular/metabolismo , Especificidade de Órgãos , Nervos Periféricos/metabolismo
9.
Chemphyschem ; 16(10): 2219-25, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-25943332

RESUMO

The formation of aqueous biphasic systems (ABS) when mixing aqueous solutions of polyethylene glycol (PEG) and an ionic liquid (IL) can be controlled by modifying the hydrogen-bond-donating/-accepting ability of the polymer end groups. It is shown that the miscibility/immiscibility in these systems stems from both the solvation of the ether groups in the oxygen chain and the ability of the PEG terminal groups to preferably hydrogen bond with water or the anion of the salt. The removal of even one hydrogen bond in PEG can noticeably affect the phase behavior, especially in the region of the phase diagram in which all the ethylene oxide (EO) units of the polymeric chain are completely solvated. In this region, removing or weakening the hydrogen-bond-donating ability of PEG results in greater immiscibility, and thus, in a higher ability to form ABS, as a result of the much weaker interactions between the IL anion and the PEG end groups.


Assuntos
Líquidos Iônicos/química , Polietilenoglicóis/química , Ligação de Hidrogênio , Estrutura Molecular , Solubilidade , Água/química
10.
Brain ; 137(Pt 3): 668-82, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24480485

RESUMO

The ganglioside-induced differentiation-associated protein 1 (GDAP1) is a mitochondrial fission factor and mutations in GDAP1 cause Charcot-Marie-Tooth disease. We found that Gdap1 knockout mice (Gdap1(-/-)), mimicking genetic alterations of patients suffering from severe forms of Charcot-Marie-Tooth disease, develop an age-related, hypomyelinating peripheral neuropathy. Ablation of Gdap1 expression in Schwann cells recapitulates this phenotype. Additionally, intra-axonal mitochondria of peripheral neurons are larger in Gdap1(-/-) mice and mitochondrial transport is impaired in cultured sensory neurons of Gdap1(-/-) mice compared with controls. These changes in mitochondrial morphology and dynamics also influence mitochondrial biogenesis. We demonstrate that mitochondrial DNA biogenesis and content is increased in the peripheral nervous system but not in the central nervous system of Gdap1(-/-) mice compared with control littermates. In search for a molecular mechanism we turned to the paralogue of GDAP1, GDAP1L1, which is mainly expressed in the unaffected central nervous system. GDAP1L1 responds to elevated levels of oxidized glutathione by translocating from the cytosol to mitochondria, where it inserts into the mitochondrial outer membrane. This translocation is necessary to substitute for loss of GDAP1 expression. Accordingly, more GDAP1L1 was associated with mitochondria in the spinal cord of aged Gdap1(-/-) mice compared with controls. Our findings demonstrate that Charcot-Marie-Tooth disease caused by mutations in GDAP1 leads to mild, persistent oxidative stress in the peripheral nervous system, which can be compensated by GDAP1L1 in the unaffected central nervous system. We conclude that members of the GDAP1 family are responsive and protective against stress associated with increased levels of oxidized glutathione.


Assuntos
Axônios/metabolismo , Doença de Charcot-Marie-Tooth/metabolismo , Mitocôndrias/metabolismo , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Animais , Células Cultivadas , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/fisiopatologia , DNA Mitocondrial/genética , Modelos Animais de Doenças , Glutationa/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Oxirredução , Estresse Oxidativo , Fenótipo
11.
Phys Chem Chem Phys ; 16(6): 2271-4, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24382570

RESUMO

The molecular-level mechanisms behind the formation of aqueous biphasic systems (ABS) composed of ionic liquids (ILs) and polymers are hitherto not completely understood. For the first time, it is herein shown that polymer-IL-based ABS are a result of a "washing-out" phenomenon, and not of a salting-out effect of the IL over the polymer as assumed in the past few years. Novel evidence is herein provided by experimental results combined with molecular dynamics (MD) simulations and density functional theory (DFT) calculations.


Assuntos
Líquidos Iônicos/química , Polietilenoglicóis/química , Água/química , Simulação de Dinâmica Molecular
12.
Biomed Chromatogr ; 28(6): 839-47, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24861752

RESUMO

Sample preparation is an important analytical step regarding the isolation and concentration of desired components from complex matrices and greatly influences their reliable and accurate analysis and data quality. It is the most labor-intensive and error-prone process in analytical methodology and, therefore, may influence the analytical performance of the target analytes quantification. Many conventional sample preparation methods are relatively complicated, involving time-consuming procedures and requiring large volumes of organic solvents. Recent trends in sample preparation include miniaturization, automation, high-throughput performance, on-line coupling with analytical instruments and low-cost operation through extremely low volume or no solvent consumption. Micro-extraction techniques, such as micro-extraction by packed sorbent (MEPS), have these advantages over the traditional techniques. This paper gives an overview of MEPS technique, including the role of sample preparation in bioanalysis, the MEPS description namely MEPS formats (on- and off-line), sorbents, experimental and protocols, factors that affect the MEPS performance, and the major advantages and limitations of MEPS compared with other sample preparation techniques. We also summarize MEPS recent applications in bioanalysis.


Assuntos
Secreções Corporais/química , Líquidos Corporais/química , Polímeros/química , Microextração em Fase Sólida/métodos , Adsorção , Animais , Humanos , Microextração em Fase Sólida/instrumentação
13.
Dent J (Basel) ; 12(8)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39195087

RESUMO

This systematic review aims to assess the impact of high (>30 Hz) and low (≤30 Hz) frequency vibrations on orthodontic tooth movement (OTM). Several articles were collected through a systematic search in the databases MEDLINE and SCOPUS, following PRISMA methodology and using a PICO question. Relevant information on selected articles was extracted, and the quality of each study was assessed by the quality assessment tools EPHPP, ROBINS-1 and STAIR. Out of 350 articles, 30 were chosen. Low-frequency vibrations did not seem to accelerate OTM with aligners or fixed appliances, despite some positive outcomes in certain studies. Conversely, high-frequency vibrations were linked to increased aligner change, tooth movement, and space closure with fixed appliances. In vivo studies reported favourable results with high-frequency vibrations (60 Hz to 120 Hz), which stimulate bone biomarkers, facilitating alveolar bone remodelling. The results suggest that high-frequency vibration effectively speeds up orthodontic tooth movement, showing promise in both in vivo and clinical studies. Larger-scale research is needed to strengthen its potential in orthodontics.

14.
Healthcare (Basel) ; 12(18)2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39337208

RESUMO

INTRODUCTION: Due to the large amount of scientific evidence on the subject and the limitations and incongruities in previous reviews, the primary aim of this umbrella review is to gather all the information regarding the importance of vitamin D levels in the osseointegration of dental implants. METHODS: The literature search was performed in PubMed, Web of Science, CINAHL Plus, Cochrane Library, and Academic Search Complete throughout the search expression ["vitamin D" AND ("dental implant" OR "dental implants")]. RESULTS: The initial search yielded 351 results, but at the end of the process, only five systematic reviews were selected. CONCLUSIONS: Vitamin D seems to have a positive effect on the osseointegration of dental implants and on the reduction of dental implant failures; however, it is recommended that future studies take into account the limitations mentioned in this study in order to increase the validity and quality of scientific evidence on the subject.

15.
Brain ; 135(Pt 12): 3567-83, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23171661

RESUMO

Studying the function and malfunction of genes and proteins associated with inherited forms of peripheral neuropathies has provided multiple clues to our understanding of myelinated nerves in health and disease. Here, we have generated a mouse model for the peripheral neuropathy Charcot-Marie-Tooth disease type 4H by constitutively disrupting the mouse orthologue of the suspected culprit gene FGD4 that encodes the small RhoGTPase Cdc42-guanine nucleotide exchange factor Frabin. Lack of Frabin/Fgd4 causes dysmyelination in mice in early peripheral nerve development, followed by profound myelin abnormalities and demyelination at later stages. At the age of 60 weeks, this was accompanied by electrophysiological deficits. By crossing mice carrying alleles of Frabin/Fgd4 flanked by loxP sequences with animals expressing Cre recombinase in a cell type-specific manner, we show that Schwann cell-autonomous Frabin/Fgd4 function is essential for proper myelination without detectable primary contributions from neurons. Deletion of Frabin/Fgd4 in Schwann cells of fully myelinated nerve fibres revealed that this protein is not only required for correct nerve development but also for accurate myelin maintenance. Moreover, we established that correct activation of Cdc42 is dependent on Frabin/Fgd4 function in healthy peripheral nerves. Genetic disruption of Cdc42 in Schwann cells of adult myelinated nerves resulted in myelin alterations similar to those observed in Frabin/Fgd4-deficient mice, indicating that Cdc42 and the Frabin/Fgd4-Cdc42 axis are critical for myelin homeostasis. In line with known regulatory roles of Cdc42, we found that Frabin/Fgd4 regulates Schwann cell endocytosis, a process that is increasingly recognized as a relevant mechanism in peripheral nerve pathophysiology. Taken together, our results indicate that regulation of Cdc42 by Frabin/Fgd4 in Schwann cells is critical for the structure and function of the peripheral nervous system. In particular, this regulatory link is continuously required in adult fully myelinated nerve fibres. Thus, mechanisms regulated by Frabin/Fgd4-Cdc42 are promising targets that can help to identify additional regulators of myelin development and homeostasis, which may crucially contribute also to malfunctions in different types of peripheral neuropathies.


Assuntos
Doença de Charcot-Marie-Tooth/patologia , Proteínas dos Microfilamentos/metabolismo , Bainha de Mielina/metabolismo , Bainha de Mielina/patologia , Células de Schwann/metabolismo , Fatores Etários , Animais , Células Cultivadas , Doença de Charcot-Marie-Tooth/genética , Modelos Animais de Doenças , Estimulação Elétrica , Endocitose/efeitos dos fármacos , Endocitose/genética , Potencial Evocado Motor/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Transgênicos , Proteínas dos Microfilamentos/genética , Microscopia Eletrônica de Transmissão , Mutação/genética , Proteína Proteolipídica de Mielina/genética , Bainha de Mielina/genética , RNA Interferente Pequeno/farmacologia , Células de Schwann/efeitos dos fármacos , Células de Schwann/ultraestrutura , Nervo Isquiático/citologia , Nervo Isquiático/patologia , Nervo Isquiático/fisiopatologia , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Transferrina/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo
16.
Sci Total Environ ; 892: 164531, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37268142

RESUMO

Polystyrene (PS) is a crucial material for modern plastic manufacturers, but its widespread use and direct discard in the environment severely affect the food chain. This review provides a detailed study on the impact of PS microplastics (PS-MPs) on the food chain and the environment, including information on their mechanism, degradation process, and toxicity. The accumulation of PS-MPs in organisms' different organs leads to various adverse reactions, such as reduced body weight, premature deaths, pulmonary diseases, neurotoxicity, transgenerational issues, oxidative stress, metabolic alterations, ecotoxicity, immunotoxicity, and other dysfunctions. These consequences affect diverse elements in the food chain, spanning from aquatic species to mammals and humans. The review also addresses the need for sustainable plastic waste management policies and technological developments to prevent the adverse impacts of PS-MPs on the food chain. Additionally, it emphasizes the importance of developing a precise, flexible, and effective methodology for extracting and quantifying PS-MPs in food, considering their characteristics like particle size, polymer types, and forms. While several studies have focused on the toxicity of polystyrene microplastics (PS-MPs) in aquatic species, further investigation is required to understand the mechanisms by which they are transferred across multiple trophic levels. Therefore, this article serves as the first comprehensive review, examining the mechanism, degradation process, and toxicity of PS-MPs. It presents an analysis of the current research landscape of PS-MPs in the global food chain, providing insights for future researchers and governing organizations to adopt better approaches to managing PS-MPs and preventing their adverse impacts on the food chain. As far as we know this is the first article on this specific and impactant topic.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Animais , Microplásticos/toxicidade , Poliestirenos/toxicidade , Plásticos/toxicidade , Cadeia Alimentar , Peso Corporal , Poluentes Químicos da Água/toxicidade , Mamíferos
17.
Bioresour Technol ; 386: 129549, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37499926

RESUMO

Lignocellulosic byproducts, mainly generated by the agro-industrial sector, have great potential as cost-effective feedstocks for bioprocesses because of their abundant availability and high content of sugar-rich and nutrient-rich elements. This biomass can be employed as a carbon source to produce various molecules using several microorganisms. Yeast strains have shown their capability to metabolize diverse C5 and C6 carbon sources, thereby facilitating their use in the bioprocessing of lignocellulosic biomass. Furthermore, yeasts can produce a wide range of valuable products, including biofuels, enzymes, proteins, and pigments, making them attractive for use in integrated biorefineries. Yeast-derived pigments have versatile applications and are environmentally friendly alternatives to their synthetic counterparts. This review emphasizes the potential of lignocellulosic biomass as a feedstock for producing yeast-derived products with a focus on pigments as valuable molecules. It also proposes a yeast-derived pigment platform utilizing lignocellulosic byproducts and explores its potential integration in biorefineries.


Assuntos
Lignina , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Lignina/metabolismo , Biocombustíveis , Biomassa
18.
Glia ; 60(10): 1518-28, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22729949

RESUMO

Missense mutations affecting the LITAF gene (also known as SIMPLE) lead to the dominantly inherited peripheral neuropathy Charcot-Marie-Tooth disease type 1C (CMT1C). In this study, we sought to determine the requirement of Litaf function in peripheral nerves, the only known affected tissue in CMT1C. We reasoned that this knowledge is a prerequisite for a thorough understanding of the underlying disease mechanism with regard to potential contributions by Litaf loss of function. In addition, we anticipated to obtain valuable information about the basic function of the Litaf protein in peripheral nerves. To address these issues, we generated mice without Litaf expression using gene disruption in embryonic stem cells and analyzed Litaf-deficient peripheral nerves during development, in maintenance, and after injury. Our results show that Litaf function is not absolutely required for peripheral nerve development and maintenance. In injured nerves, however, we found that lack of Litaf led to increased numbers of macrophages during Wallerian degeneration, accelerated myelin destruction, and the emergence of more axonal sprouts. Consistent with these data, the migration of Litaf-deficient macrophages was increased upon chemokine stimulation. We conclude that loss of Litaf function is unlikely to be a major contributor to CMT1C, but modulating effects of macrophages need to be considered in the etiology of the disease.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas Nucleares/metabolismo , Nervos Periféricos/crescimento & desenvolvimento , Nervos Periféricos/metabolismo , Fatores de Transcrição/metabolismo , Degeneração Walleriana/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Células Cultivadas , Proteínas de Ligação a DNA , Modelos Animais de Doenças , Regulação da Expressão Gênica no Desenvolvimento/genética , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão , Mutação/genética , Bainha de Mielina/metabolismo , Fibras Nervosas/patologia , Fibras Nervosas/ultraestrutura , Proteínas Nucleares/genética , Nervos Periféricos/ultraestrutura , Neuropatia Ciática/complicações , Neuropatia Ciática/patologia , Fatores de Transcrição/genética , Degeneração Walleriana/etiologia , Degeneração Walleriana/patologia
19.
Restor Dent Endod ; 47(3): e26, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36090516

RESUMO

Wegener's granulomatosis (WG) is a condition with immune-mediated pathogenesis that can present oral manifestations. This report describes the case of a patient diagnosed with WG 14 years previously, who was affected by persistent pain of non-odontogenic origin after successful endodontic treatment. A 39-year-old woman with WG was diagnosed with pulp necrosis and apical periodontitis of teeth #31, #32, and #41, after evaluation through a clinical examination and cone-beam computed tomography (CBCT). At the first appointment, these teeth were subjected to conventional endodontic treatment. At 6- and 12-month follow-up visits, the patient complained of persistent pain associated with the endodontically treated teeth (mainly in tooth #31), despite complete remission of the periapical lesions shown by radiographic and CBCT exams proving the effectiveness of the endodontic treatments, thus indicating a probable diagnostic of persistent pain of non-odontogenic nature. After the surgical procedure was performed to curette the lesion and section 3 mm of the apical third of tooth #31, the histopathological analysis suggested that the painful condition was likely associated with the patient's systemic condition. Based on clinical, radiographic, and histopathological findings, this unusual case report suggests that WG may be related to non-odontogenic persistent pain after successful endodontic treatments.

20.
J Dent Anesth Pain Med ; 21(4): 269-282, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34395896

RESUMO

This review aimed to assess and compare the outcomes of the anesthetic efficacy of inferior alveolar nerve block (IANB) and Gow-Gates mandibular nerve block (GGMNB) in patients with symptomatic irreversible pulpitis. A descriptive systematic review of quantitative research was conducted wherein the "Preferred Reporting Items for Systematic Reviews (PRISMA)" was adopted, and the Problem/Patient/Population, Intervention/Indicator, Comparison, Outcome (PICO) criteria were used to structure the research question. A literature search was performed using PubMed/Medline, Cochrane Library, Google Scholar, and Ovid. Selection criteria were applied for populations over nine years of age, of either sex, with irreversible pulpitis, and articles published in English regarding conventional IANB or IANB and Gow-Gates techniques between 2009 and 2019. Prospective randomized clinical trials or randomized controlled trials were included in the review, in which anesthetic efficacy or success was measured. After screening, four articles were included. Three studies were randomized clinical trials, and two were randomized controlled trials. The validity and reliability of the individual studies were examined. There was evidence of the higher efficacy of the GGMNB technique than that of the IANB technique. However, both techniques can be mastered through training.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA