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1.
Braz Oral Res ; 38: e087, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39292126

RESUMO

This study employed e-Vol DXS cone beam computed tomography (CBCT) software to assess dentin remnants in the furcation area of mesial canals in mandibular molars during root canal retreatment (RCR). Four groups (Reciproc®, ProTaper Next®, Race Evo®, Protaper Gold®) were subjected to RCR, and CBCT images were captured before (T1) and after (T2) treatment. Measurements of remaining dentin thickness at 1 mm and 3 mm below the furcation were scrutinized. Results revealed no significant differences in mean thicknesses of mesiobuccal (MB) and mesiolingual (ML) canals at 1 mm and 3 mm from the furcation pre-treatment (T1). Post-treatment (T2) showed analogous findings, with no significant differences in mean thicknesses. However, disparities were found between MB and ML canals at both distances, both before and after retreatment. In essence, the evaluated instruments exhibited safety in RCR, implying that they are appropriate for use in critical areas of mandibular molars without inducing excessive wear. This study underscores the reliability of these instruments in navigating danger zones during RCR, and contributes valuable insights for dental practitioners who handle complex root canal scenarios in mandibular molars.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar , Dentina , Mandíbula , Dente Molar , Retratamento , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Molar/diagnóstico por imagem , Dente Molar/anatomia & histologia , Retratamento/métodos , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , Reprodutibilidade dos Testes , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/anatomia & histologia , Dentina/diagnóstico por imagem , Instrumentos Odontológicos , Tratamento do Canal Radicular/métodos , Tratamento do Canal Radicular/instrumentação , Valores de Referência , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Desenho de Equipamento , Estatísticas não Paramétricas
2.
J Chem Theory Comput ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235392

RESUMO

Coarse-grained molecular dynamics simulations enable the modeling of increasingly complex systems at millisecond timescales. The transferable coarse-grained force field Martini 3 has shown great promise in modeling a wide range of biochemical processes, yet folded proteins in Martini 3 are not stable without the application of external bias potentials, such as elastic networks or Go̅-like models. We herein develop an algorithm, called OLIVES, which identifies native contacts with hydrogen bond capabilities in coarse-grained proteins and use it to implement a novel Go̅-like model for Martini 3. We show that the protein structure instability originates in part from the lack of hydrogen bond energy in the coarse-grained force field representation. By using realistic hydrogen bond energies obtained from literature ab initio calculations, it is demonstrated that protein stability can be recovered by the reintroduction of a coarse-grained hydrogen bond network and that OLIVES removes the need for secondary structure restraints. OLIVES is validated against known protein complexes and at the same time addresses the open question of whether there is a need for protein quaternary structure bias in Martini 3 simulations. It is shown that OLIVES can reduce the number of bias terms, hereby speeding up Martini 3 simulations of proteins by up to ≈30% on a GPU architecture compared to the established Go̅MARTINI Go̅-like model.

3.
J Nutr Biochem ; : 109747, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39197728

RESUMO

Although previous studies demonstrated that the ancestral lifestyle can enhance the metabolic health of offspring exposed to an obesogenic diet, the specific connections between these positive effects in redox state and telomere length are unknown. We investigated the impact of paternal resistance training (RT) on stress-responsive signaling and the pathways involved in telomere homeostasis in skeletal muscle. This investigation encompassed both the fathers and first-generation litter exposed to a long-term standard diet (24 weeks) and high fat diet (HFD). Wistar rats were randomized into sedentary or trained fathers (8 weeks of resistance training). The offspring were obtained by mating with sedentary females. Upon weaning, male offspring were divided into four groups: offspring of sedentary or trained fathers exposed to either a control diet or HFD. The gastrocnemius was prepared for reverse transcription-quantitative polymerase chain reaction, immunoblotting, ELISA, and electron paramagnetic resonance spectroscopy. RT upregulated shelterin mRNA levels and antioxidant protein, preserving muscle telomere in fathers. Conversely, HFD induced a disturbance in the redox balance, which may have contributed to the offspring telomere shortening from sedentary fathers. Pre-conceptional paternal RT downregulates Kelch-like ECH-associated protein 1 (Keap1) mRNA levels in the skeletal muscle of progeny exposed to HFD, driving an increase in Glutathione reductase mRNA levels, Sod1 and Catalase protein levels to mitigate ROS production. Also, paternal exercise upregulates α-Klotho protein levels, mediating antioxidative responses without altering shelterin mRNA levels and telomere length. We provide the first in-depth analysis that the offspring's redox state seems to be directly associated with the beneficial effects of paternal exercise.

4.
Clin Genet ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39099467

RESUMO

There are few cerebrotendineous xanthomatosis (CTX) case series and observational studies including a significant number of Latin American patients. We describe a multicenter Brazilian cohort of patients with CTX highlighting their clinical phenotype, recurrent variants and assessing possible genotype-phenotype correlations. We analyzed data from all patients with clinical and molecular or biochemical diagnosis of CTX regularly followed at six genetics reference centers in Brazil between March 2020 and August 2023. We evaluated 38 CTX patients from 26 families, originating from 4 different geographical regions in Brazil. Genetic analysis identified 13 variants in the CYP27A1 gene within our population, including 3 variants that had not been previously described. The most frequent initial symptom of CTX in Brazil was cataract (27%), followed by xanthomas (24%), chronic diarrhea (13.5%), and developmental delay (13.5%). We observed that the median age at loss of ambulation correlates with the age of onset of neurological symptoms, with an average interval of 10 years (interquartile range 6.9 to 11 years). This study represents the largest CTX case series ever reported in South America. We describe phenotypic characteristics and report three new pathogenic or likely pathogenic variants.

5.
Int J Biol Macromol ; 278(Pt 1): 134219, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39097041

RESUMO

Cholesterol is a major component of plasma membranes and plays a significant role in actively regulating the functioning of several membrane proteins in humans. In this study, we focus on the role of cholesterol depletion on the voltage-gated sodium channel Nav1.7, which is primarily expressed in the peripheral sensory neurons and linked to various chronic inherited pain syndromes. Coarse-grained molecular dynamics simulations revealed key dynamic changes of Nav1.7 upon membrane cholesterol depletion: A loss of rigidity in the structural motifs linked to activation and fast-inactivation is observed, suggesting an easier transition of the channel between different gating states. In-vitro whole-cell patch clamp experiments on HEK293t cells expressing Nav1.7 validated these predictions at the functional level: Hyperpolarizing shifts in the voltage-dependence of activation and fast-inactivation were observed along with an acceleration of the time to peak and onset kinetics of fast inactivation. These results underline the critical role of membrane composition, and of cholesterol in particular, in influencing Nav1.7 gating characteristics. Furthermore, our results also point to cholesterol-driven changes of the geometry of drug-binding regions, hinting to a key role of the membrane environment in the regulation of drug effects.


Assuntos
Membrana Celular , Colesterol , Simulação de Dinâmica Molecular , Canal de Sódio Disparado por Voltagem NAV1.7 , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.7/química , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Humanos , Colesterol/metabolismo , Colesterol/química , Membrana Celular/metabolismo , Membrana Celular/química , Células HEK293 , Ativação do Canal Iônico
6.
Rev. Bras. Neurol. (Online) ; 60(2): 21-27, abr.-jun. 2024. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1566263

RESUMO

Introdução: A Síndrome da Pessoa Rígida é uma doença neuroimunológica rara do sistema nervoso central caracterizada por espasmos dolorosos e rigidez progressiva que envolvem os músculos proximais dos membros e axiais do tronco. A forma clássica tem início insidioso com piora gradual ao longo do tempo e muitas vezes leva à incapacidade permanente. Objetivo: Analisar os estudos publicados na literatura científica que utilizaram a reabilitação fisioterapêutica como proposta de tratamento dos sintomas motores na Síndrome da Pessoa Rígida. Método: Trata-se de uma revisão integrativa da literatura realizada no período de julho a dezembro de 2022 nas bases de dados PubMed, SciELO, LILACS e BVS. Resultados: Foram encontrados 12 artigos publicados entre o período de 2002 a 2021, que discorriam sobre o tratamento fisioterapêutico nesta população. O número escasso de estudos se dá pela raridade da patologia que dificulta a realização de ensaios clínicos robustos. Os artigos selecionados eram relatos de casos de um ou mais indivíduos, com enfoque nas intervenções realizadas de acordo com cada queixa funcional apresentada, sendo estas a dor, fraqueza muscular, hipomobilidade articular, rigidez, instabilidade postural, alterações na marcha e limitações nas atividades de vida diária. Conclusão: A reabilitação fisioterapêutica faz parte do tratamento sintomatológico e tem como finalidade, auxiliar na manutenção da funcionalidade e qualidade de vida, minimizando as repercussões motoras que são desencadeadas pela síndrome.


Introduction: Stiff Person Syndrome is a rare neuroimmunological disease of the central nervous system characterized by painful spasms and progressive rigidity involving the proximal muscles of the limbs and axial muscles of the trunk. The classic form has an insidious onset with gradual worsening over time and often leads to permanent disability. Objective: To analyze the studies published in the scientific literature that used hysiotherapeutic rehabilitation as a proposal for treating motor symptoms in Stiff Person Syndrome. Method: This is an integrative review of the literature carried out from July to December 2022 in the PubMed, SciELO, LILACS and VHL databases. Results: 12 articles published between 2002 and 2021 were found, which discussed physiotherapeutic treatment in this population. The scarce number of studies is due to the rarity of the pathology, which makes it difficult to carry out robust clinical trials. The selected articles were case reports of one or more individuals, focusing on interventions carried out according to each functional complaint presented, these being pain, muscle weakness, joint hypomobility, stiffness, postural instability, changes in gait and limitations in walking activities. daily life. Conclusion: Physiotherapy rehabilitation is part of symptomatological treatment and aims to help maintain functionality and quality of life, minimizing the motor repercussions that are triggered by the syndrome.

7.
Pharmaceutics ; 16(7)2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39065638

RESUMO

Photodynamic therapy (PDT) uses a photosensitizer to generate reactive oxygen species (ROS) that kill target cells. In cancer treatments, PDT can potentially induce immunogenic cell death (ICD), which is characterized by a well-controlled exposure of damage-associated molecular patterns (DAMPs) that activate dendritic cells (DCs) and consequently modulate the immune response in the tumor microenvironment. However, PDT still has limitations, such as the activity of photosensitizers in aqueous media and poor bioavailability. Therefore, a new photosensitizer system, SLN-AlPc, has been developed to improve the therapeutic efficacy of PDT. In vitro experiments showed that the light-excited nanocarrier increased ROS production in murine melanoma B16-F10 cells and modulated the profile of DCs. PDT induced cell death accompanied by the exposure of DAMPs and the formation of autophagosomes. In addition, the DCs exposed to PDT-treated B16-F10 cells exhibited morphological changes, increased expression of MHCII, CD86, CD80, and production of IL-12 and IFN-γ, suggesting immune activation towards an antitumor profile. These results indicate that the SLNs-AlPc protocol has the potential to improve PDT efficacy by inducing ICD and activating DCs.

8.
Genet Mol Biol ; 47(2): e20230235, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39058384

RESUMO

We predicted miRNAs with regulatory impact on NFKB1 and TRAF6 gene expression and selected the miR-194-5p, miR-124-3p, miR-9-5p, and miR-340-5p and their target genes for expression analyses on CD14+ monocytes from rheumatoid arthritis (RA) patients and healthy controls. Additionally, we evaluated the influence of genes and miRNA expression on RA patients' cytokine levels. No difference was observed in genes or miRNAs expression when compared to healthy controls and RA patients or clinical parameters. However, we found a significant difference between miR-194-5p and miR-9-5p levels (FC=-2.31; p=0.031; FC=-3.05;p=0.031, respectively) and non-prednisone users as compared to prednisone using patients. We conducted correlation analyses to identify the strength of the relationship between expression data and cytokine plasma levels. We observed a moderate positive correlation between miR-124-3p expression and IL-6 plasma levels (r=0.46; p=0.033). In addition, overexpression of miRNAs was concomitant to TRAF6 and NFKB1 genes as indicated by correlation analyses: TRAF6 and miR-194-5p (r=0.60;p<0.001) and miR-9-5p (r=0.63;p<0.001) and NFKB1 and miR-194-5p (r=0.72;p<0.001), miR-9-5p (r=0.72;p<0.001) and miR-340-5p (r=0.61;p<0.001). NFKB1 and TRAF6 genes and miRNAs monocyte expression do not appear to be related to RA but showed a significant difference in different groups of RA therapy. In addition, increased levels of miRNAs can be linked to concomitant overexpression of TRAF6 and NFKB1 in monocytes and act as its regulators.

9.
Clin Genet ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39015008

RESUMO

Limb-girdle muscular dystrophy type 2G/R7 (LGMD2G/R7) is an ultra-rare condition initially identified within the Brazilian population. We aimed to expand clinical and genetic information about this disease, including its worldwide distribution. A multicenter historical cohort study was performed at 13 centers in Brazil in which data from index cases and their affected relatives from consecutive families with LGMD2G/R7 were reviewed from July 2017 to August 2023. Additionally, a systematic literature review was conducted to identify case reports and series of the disease worldwide. Forty-one LGMD2G/R7 cases were described in the Brazilian cohort, being all subjects homozygous for the c.157C>T/(p.Gln53*) variant in TCAP. Survival curves showed that the median disease duration before individuals required walking aids was 21 years. Notably, women exhibited a slower disease progression, requiring walking aids 13 years later than men. LGMD2G/R7 was frequently reported not only in Brazil but also in China and Bulgaria, with 119 cases identified globally, with possible founder effects in the Brazilian, Eastern European, and Asian populations. These findings are pivotal in raising awareness of LGMD2G/R7, understanding its progression, and identifying potential modifiers. This can significantly contribute to the development of future natural history studies and clinical trials for this disease.

10.
J Chem Theory Comput ; 20(13): 5763-5773, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38924075

RESUMO

Coarse-grained (CG) molecular dynamics (MD) simulations have grown in applicability over the years. The recently released version of the Martini CG force field (Martini 3) has been successfully applied to simulate many processes, including protein-ligand binding. However, the current ligand parametrization scheme is manual and requires an a priori reference all-atom (AA) simulation for benchmarking. For systems with suboptimal AA parameters, which are often unknown, this translates into a CG model that does not reproduce the true dynamical behavior of the underlying molecule. Here, we present Bartender, a quantum mechanics (QM)/MD-based parametrization tool written in Go. Bartender harnesses the power of QM simulations and produces reasonable bonded terms for Martini 3 CG models of small molecules in an efficient and user-friendly manner. For small, ring-like molecules, Bartender generates models whose properties are indistinguishable from the human-made models. For more complex, drug-like ligands, it is able to fit functional forms beyond simple harmonic dihedrals and thus better captures their dynamical behavior. Bartender has the power to both increase the efficiency and the accuracy of Martini 3-based high-throughput applications by producing numerically stable and physically realistic CG models.


Assuntos
Simulação de Dinâmica Molecular , Teoria Quântica , Ligantes , Proteínas/química
11.
World J Microbiol Biotechnol ; 40(8): 248, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904740

RESUMO

This manuscript presents a new report on the in vitro antimicrobial photo-inactivation of foodborne microorganisms (Salmonella spp. and Listeria monocytogenes) using tetra-cationic porphyrins. Isomeric tetra-cationic porphyrins (3MeTPyP, 4MeTPyP, 3PtTPyP, and 4PtTPyP) were tested, and antimicrobial activity assays were performed at specific photosensitizer concentrations under dark and white-light LED irradiation conditions. Among the tested bacterial strains, 4MeTPyP exhibited the highest efficiency, inhibiting bacterial growth within just 60 min at low concentrations (17.5 µM). The minimal inhibitory concentration of 4MeTPyP increased when reactive oxygen species scavengers were present, indicating the significant involvement of singlet oxygen species in the photooxidation mechanism. Furthermore, the checkerboard assay testing the association of 4MeTPyP showed an indifferent effect. Atomic force microscopy analyses and dynamic simulations were conducted to enhance our understanding of the interaction between this porphyrin and the strain's membrane.


Assuntos
Biofilmes , Listeria monocytogenes , Testes de Sensibilidade Microbiana , Simulação de Dinâmica Molecular , Fármacos Fotossensibilizantes , Porfirinas , Porfirinas/farmacologia , Porfirinas/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Biofilmes/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Microbiologia de Alimentos , Antibacterianos/farmacologia , Antibacterianos/química , Microscopia de Força Atômica , Espécies Reativas de Oxigênio/metabolismo , Luz , Oxigênio Singlete/metabolismo , Oxigênio Singlete/química
12.
J Oral Rehabil ; 51(8): 1589-1598, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797958

RESUMO

BACKGROUND: Symptomatic irreversible pulpitis often results in heightened reactions to thermal stimuli such as pain evoked by a cold stimulus, and spontaneous odontogenic pain (unprovoked pain). OBJECTIVE: This study primarily compared the clinical manifestations of odontogenic spontaneous pain and pain provoked by cold stimulus specifically focusing on their sensory discriminative characteristics (intensity, duration and quality) between symptomatic irreversible pulpitis patients with and without referred pain. METHODS: Twenty-three patients with symptomatic irreversible pulpitis with referred pain and 12 patients without referred pain were included in this cross-sectional study. The following outcomes were assessed: odontogenic spontaneous pain and its descriptors; pain evoked by cold stimulus and qualitative sensory testing before and after local anaesthesia; referred pain location; use of analgesic medication; complementary anaesthesia efficacy. T-test, chi-squared and McNemar tests were applied to the data (p < .50). RESULTS: Patients with referred pain presented a greater odontogenic pain intensity (p < .05) when considered the average of the last 24 h. These patients also showed higher pain rating and pain descriptors (p < .05). Intensity and duration of the pain evoked by cold stimulus in the non-affected contralateral tooth at baseline were higher for patients with referred pain (p < .05). CONCLUSION: Symptomatic irreversible pulpitis patients with referred pain present greater odontogenic spontaneous pain and a heightened pain sensitivity. Therefore, patients with referred pain seem more complex from a pain severity perspective, supporting the clinical utility of discriminating symptomatic irreversible pulpitis with and without referred pain.


Assuntos
Medição da Dor , Limiar da Dor , Dor Referida , Pulpite , Odontalgia , Humanos , Pulpite/fisiopatologia , Pulpite/complicações , Feminino , Masculino , Estudos Transversais , Adulto , Dor Referida/fisiopatologia , Limiar da Dor/fisiologia , Odontalgia/fisiopatologia , Pessoa de Meia-Idade , Temperatura Baixa , Adulto Jovem
14.
Orphanet J Rare Dis ; 19(1): 188, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715109

RESUMO

BACKGROUND: X-linked myotubular myopathy (XLMTM) is a rare, life-threatening congenital disease, which is not well-defined. To our knowledge, no studies characterizing the XLMTM disease burden have been conducted in Brazil. We identified and described patients with suspected XLMTM using administrative claims data from the Brazilian public healthcare system. METHODS: Data from 2015 to 2019 were extracted from the DATASUS database. As no XLMTM-specific ICD-10 code was available, a stepwise algorithm was applied to identify patients with suspected XLMTM by selecting male patients with a congenital myopathies code (G71.2), aged < 18 years at index date (first claim of G71.2), with an associated diagnostic procedure (muscle biopsy/genetic test) and without spinal muscular atrophy or Duchenne muscular dystrophy. We attempted to identify patients with suspected severe XLMTM based on use of both respiratory and feeding support, which are nearly universal in the care of XLMTM patients. Analyses were performed for the overall cohort and stratified by age at index date < 5 years old and ≥ 5 years old. RESULTS: Of 173 patients with suspected XLMTM identified, 39% were < 5 years old at index date. Nearly all (N = 166) patients (96%) were diagnosed by muscle biopsy (91% of patients < 5 years old and 99% of patients ≥ 5 years old), six (3.5%) were diagnosed by clinical evaluation (8% of patients < 5 years old and 1% of patients ≥ 5 years old), and one was diagnosed by a genetic test. Most patients lived in Brasilia (n = 55), São Paulo (n = 33) and Minas Gerais (n = 27). More than 85% of patients < 5 years old and approximately 75% of patients ≥ 5 years old had physiotherapy at the index date. In both age groups, nearly 50% of patients required hospitalization at some point and 25% required mobility support. Respiratory and feeding support were required for 3% and 12% of patients, respectively, suggesting that between 5 and 21 patients may have had severe XLMTM. CONCLUSION: In this real-world study, genetic testing for XLMTM appears to be underutilized in Brazil and may contribute to underdiagnosis of the disease. Access to diagnosis and care is limited outside of specific regions with specialized clinics and hospitals. Substantial use of healthcare resources included hospitalization, physiotherapy, mobility support, and, to a lesser extent, feeding support and respiratory support.


Assuntos
Miopatias Congênitas Estruturais , Humanos , Miopatias Congênitas Estruturais/diagnóstico , Miopatias Congênitas Estruturais/patologia , Masculino , Brasil , Criança , Adolescente , Pré-Escolar , Lactente , Atenção à Saúde , Feminino , Adulto Jovem , Adulto
15.
Future Microbiol ; 19(6): 495-508, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629920

RESUMO

Aim: To evaluate the action of promethazine, fluoxetine and carbonyl cyanide 3-chlorophenylhydrazone as efflux pump inhibitors (EPIs) against multidrug-resistant Pseudomonas aeruginosa. Methods: The effect of the compounds was evaluated in planktonic cells and bacterial biofilms. Accumulation tests were performed with ethidium bromide to prove their action as EPIs. Then, they were associated with antimicrobials. Results: Effect on planktonic cells and biofilms was found. Assays with ethidium bromide indicate their action as EPIs. Significant reductions in the metabolic activity of biofilms were observed after the association with the antimicrobials, especially for meropenem. Conclusion: It is possible to prove the action of these compounds as EPIs for P. aeruginosa and demonstrate the relevance of efflux pumps in antimicrobial resistance.


[Box: see text].


Assuntos
Antibacterianos , Biofilmes , Reposicionamento de Medicamentos , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa , Pseudomonas aeruginosa/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Prometazina/farmacologia , Proteínas de Membrana Transportadoras/metabolismo , Humanos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Hidrazonas
16.
Biochim Biophys Acta Proteins Proteom ; 1872(4): 141014, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38670324

RESUMO

Coarse-grained (CG) protein models have become indispensable tools for studying many biological protein details, from conformational dynamics to the organization of protein macro-complexes, and even the interaction of proteins with other molecules. The Martini force field is one of the most widely used CG models for bio-molecular simulations, partly because of the enormous success of its protein model. With the recent release of a new and improved version of the Martini force field - Martini 3 - a new iteration of its protein model was also made available. The Martini 3 protein force field is an evolution of its Martini 2 counterpart, aimed at improving many of the shortcomings that had been previously identified. In this mini-review, we first provide a general overview of the model and then focus on the successful advances made in the short time since its release, many of which would not have been possible before. Furthermore, we discuss reported limitations, potential directions for model improvement and comment on what the likely future development and application avenues are.


Assuntos
Simulação de Dinâmica Molecular , Conformação Proteica , Proteínas , Proteínas/química , Proteínas/metabolismo , Humanos
17.
Fitoterapia ; 175: 105949, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38583636

RESUMO

Aristolochia plants are emblematic from an ethnopharmacological viewpoint and are know to possess numerous biological properties, including antiseptic. However, the medicinal potential of these species is debatable because of their representative chemical constituents, aristolochic acids (AAs) and aristolactams (ALs), which are associated, for instance, with nephropathy and cancer. These contrasting issues have stimulated the development of approaches intended to detoxification of aristoloquiaceous biomasses, among which is included the bioconversion method using larvae of the specialist phytophagous insect Battus polydamas, previously shown to be viable for chemical diversification and to reduce toxicity. Thus, eleven Aristolochia spp. were bioconverted, and the antimicrobial activities of the plant methanolic extracts and its respective bioconversion products were evaluated. The best results were found for Aristolochia esperanzae, Aristolochia gibertii, and Aristolochia ringens against Bacillus cereus, with MIC ranging from 7.8 to 31.25 µg/mL. These three species were selected for chemical, antioxidant, cytotoxic, hemolytic, and mutagenic analyses. Chemical analysis revealed 65 compounds, 21 of them possible bioconversion products. The extracts showed potential to inhibit the formation and degradation of B. cereus biofilms. Extracts of A. gibertii and its bioconverted biomass showed antioxidant activity comparable to dibutylhydroxytoluene (BHT) standard. Bioconversion decreased the hemolytic activity of A. esperanzae and the cytotoxicities of A. esperanzae and A. gibertii. None of the extracts was found to be mutagenic. The bioactivities of the fecal extracts were maintained, and biocompatibility was improved. Therefore, the results obtained in this study reveal positive expectations about the natural detoxification process of the Aristolochia species.


Assuntos
Aristolochia , Extratos Vegetais , Aristolochia/química , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Larva/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Testes de Sensibilidade Microbiana , Humanos , Antioxidantes/farmacologia , Bacillus cereus/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/química , Mariposas/efeitos dos fármacos
18.
Pharmaceutics ; 16(4)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38675171

RESUMO

Cutaneous leishmaniasis (CL) is a neglected tropical disease. The treatment is restricted to drugs, such as meglumine antimoniate and amphotericin B, that exhibit toxic effects, high cost, long-term treatment, and limited efficacy. The development of new alternative therapies, including the identification of effective drugs for the topical and oral treatment of CL, is of great interest. In this sense, a combination of topical photodynamic therapy (PDT) with chloroaluminum phthalocyanine liposomes (Lip-ClAlPc) and the oral administration of a self-emulsifying drug delivery system containing fexinidazole (SEDDS-FEX) emerges as a new strategy. The aim of the present study was to prepare, characterize, and evaluate the efficacy of combined therapy with Lip-ClAlPc and SEDDS-FEX in the experimental treatment of Leishmania (Leishmania) major. Lip-ClAlPc and SEDDS-FEX were prepared, and the antileishmanial efficacy study was conducted with the following groups: 1. Lip-ClAlPc (0.05 mL); 2. SEDDS-FEX (50 mg/kg/day); 3. Lip-ClAlPc (0.05 mL)+SEDDS-FEX (50 mg/kg/day) combination; 4. FEX suspension (50 mg/kg/day); and 5. control (untreated). BALB/c mice received 10 sessions of topical Lip-ClAlPc on alternate days and 20 consecutive days of SEDDS-FEX or FEX oral suspension. Therapeutical efficacy was evaluated via the parasite burden (limiting-dilution assay), lesion size (mm), healing of the lesion, and histological analyses. Lip-ClAlPc and SEDDS-FEX presented physicochemical characteristics that are compatible with the administration routes used in the treatments. Lip-ClAlPc+SEDDS-FEX led to a significant reduction in the parasitic burden in the lesion and spleen when compared to the control group (p < 0.05) and the complete healing of the lesion in 43% of animals. The Lip-ClAlPc+SEDDS-FEX combination may be promising for the treatment of CL caused by L. major.

19.
Plant Cell Environ ; 47(7): 2542-2560, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38518065

RESUMO

Thioredoxins (TRXs) are central to redox regulation, modulating enzyme activities to adapt metabolism to environmental changes. Previous research emphasized mitochondrial and microsomal TRX o1 and h2 influence on mitochondrial metabolism, including photorespiration and the tricarboxylic acid (TCA) cycle. Our study aimed to compare TRX-based regulation circuits towards environmental cues mainly affecting photorespiration. Metabolite snapshots, phenotypes and CO2 assimilation were compared among single and multiple TRX mutants in the wild-type and the glycine decarboxylase T-protein knockdown (gldt1) background. Our analyses provided evidence for additive negative effects of combined TRX o1 and h2 deficiency on growth and photosynthesis. Especially metabolite accumulation patterns suggest a shared regulation mechanism mainly on mitochondrial dihydrolipoamide dehydrogenase (mtLPD1)-dependent pathways. Quantification of pyridine nucleotides, in conjunction with 13C-labelling approaches, and biochemical analysis of recombinant mtLPD1 supported this. It also revealed mtLPD1 inhibition by NADH, pointing at an additional measure to fine-tune it's activity. Collectively, we propose that lack of TRX o1 and h2 perturbs the mitochondrial redox state, which impacts on other pathways through shifts in the NADH/NAD+ ratio via mtLPD1. This regulation module might represent a node for simultaneous adjustments of photorespiration, the TCA cycle and branched chain amino acid degradation under fluctuating environmental conditions.


Assuntos
Di-Hidrolipoamida Desidrogenase , Mitocôndrias , Tiorredoxinas , Di-Hidrolipoamida Desidrogenase/metabolismo , Di-Hidrolipoamida Desidrogenase/genética , Mitocôndrias/metabolismo , Tiorredoxinas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/enzimologia , Fotossíntese , Oxirredução , NAD/metabolismo , Meio Ambiente , Mutação , Dióxido de Carbono/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
20.
Biophys J ; 123(8): 1006-1014, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38486451

RESUMO

Plasma membrane damage occurs in healthy cells and more frequently in cancer cells where high growth rates and metastasis result in frequent membrane damage. The annexin family of proteins plays a key role in membrane repair. Annexins are recruited at the membrane injury site by Ca+2 and repair the damaged membrane in concert with several other proteins. Annexin A4 (ANXA4) and ANXA5 form trimers at the bilayer surface, and previous simulations show that the trimers induce high local negative membrane curvature on a flat bilayer. The membrane-curvature-inducing property of ANXA5 is presumed to be vital to the membrane repair mechanism. A previously proposed descriptive model hypothesizes that ANXA5-mediated curvature force is utilized at the free edge of the membrane at a wound site to pull the wound edges together, resulting in the formation of a "neck"-shaped structure, which, when combined with a constriction force exerted by ANXA6, leads to membrane repair. The molecular details and mechanisms of repair remain unknown, in part because the membrane edge is a transient structure that is difficult to investigate both experimentally and computationally. For the first time, we investigate the impact of ANXA5 near a membrane edge, which is modeled by a bicelle under periodic boundary conditions. ANXA5 trimers induce local curvature on the membrane leading to global bending of the bicelle. The global curvature depends on the density of annexins on the bicelle, and the curvature increases with the ANXA5 concentration until it reaches a plateau. The simulations suggest that not only do annexins induce local membrane curvature, but they can change the overall shape of a free-standing membrane. We also demonstrate that ANXA5 trimers reduce the rate of phosphatidylserine lipid diffusion from the cytoplasmic to the exoplasmic leaflet along the edge of the bicelle. In this way, membrane-bound annexins can potentially delay the apoptotic signal triggered by the presence of phosphatidylserine lipids in the outer leaflet, thus biding time for repair of the membrane hole. Our findings provide new insights into the role of ANXA5 at the edges of the membrane (the injury site) and support the curvature-constriction model of membrane repair.


Assuntos
Anexinas , Fosfatidilserinas , Anexina A5/análise , Anexina A5/metabolismo , Fosfatidilserinas/metabolismo , Membrana Celular/metabolismo , Anexinas/análise , Anexinas/química , Anexinas/metabolismo , Membranas/metabolismo
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