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1.
Pharmacol Res ; 208: 107353, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39159730

RESUMO

The therapeutic approach to many solid tumors, including non-small cell lung cancer (NSCLC), is mainly based on the use of platinum-containing anticancer agents and is often characterized by acquired or intrinsic resistance to the drug. Therefore, the search for safer and more effective drugs is still an open challenge. Two organometallic ruthenium(II)-cyclopentadienyl compounds [Ru(η5-C5H4CHO)(Me2bipy)(PPh3)]+ (RT150) and [Ru(η5-C5H4CH2OH)(Me2bipy)(PPh3)][CF3SO3] (RT151) were tested against a panel of cisplatin-resistant NSCLC cell lines and xenografts. They were more effective than cisplatin in inducing oxidative stress and DNA damage, affecting the cell cycle and causing apoptosis. Importantly, they were found to be inhibitors of drug efflux transporters. Due to this property, the compounds significantly increased the retention and cytotoxicity of cisplatin within NSCLC cells. Notably, they did not display high toxicity in vitro against non-transformed cells (red blood cells, fibroblasts, bronchial epithelial cells, cardiomyocytes, and endothelial cells). Both compounds induced vasorelaxation and reduced endothelial cell migration, suggesting potential anti-angiogenic properties. RT151 confirmed its efficacy against NSCLC xenografts resistant to cisplatin. Either alone or combined with low doses of cisplatin, RT151 showed a good biodistribution profile in the liver, kidney, spleen, lung, and tumor. Hematochemical analysis and post-mortem organ pathology confirmed the safety of the compound in vivo, also when combined with cisplatin. To sum up, we have confirmed the effectiveness of a novel class of drugs against cisplatin-resistant NSCLC. Additionally, the compounds have a good biocompatibility and safety profile.

2.
BMC Ophthalmol ; 24(1): 123, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38494487

RESUMO

INTRODUCTION: In neovascular age-related macular degeneration (nAMD) trials, anti-VEGF injection frequency decreases after the first year, while outcomes remain primarily related to the number of injections. To the best of our knowledge, there are no reports of maintaining the best corrected visual acuity (BCVA) for more than 7 years in extension studies. OBJECTIVE: To report a 12-year follow-up of a real-world case of nAMD where BCVA was preserved from declining. CASE DESCRIPTION: A 67-year-old Caucasian female presented to our department in June 2010 due to decreased vision in her left eye (LE) within the preceding months. Examination showed a BCVA of 85 letters (L) in the right eye (RE) and 35 L in the LE. Fundus examination showed drusen in the macula of both eyes. Macular edema, loss of the macular lutein pigment, macular hypo/hyperpigmentation were observed in the LE. A diagnosis of Type 2 choroidal neovascular membrane (CNV) in the LE was established and within two months a Type 1 CNV developed in the RE. She undergone 9 injections of bevacizumab (six) and ranibizumab (three) within the first year of treatment in the LE and seven injections of ranibizumab within the first year in the RE. RESULTS: The LE had a mean of 5.2 injections per year, and the RE had a mean of 7.5 injections per year, from 2010 to 2022. RE's BCVA dropped by 8L (85L to 77L) and central retinal thickness (CRT) increased by 16 µm (276 µm to 292 µm) while LE's BCVA increased by 28L (35L to 63L) and CRT decreased by 369 µm (680 µm to 311 µm), at the twelfth year. CONCLUSIONS: Although the final visual outcome depends on baseline BCVA and lesion type or size, the number of injections is paramount in preserving BCVA and achieving favorable functional outcomes in nAMD, even after 12 years of treatment.


Assuntos
Neovascularização de Coroide , Edema Macular , Humanos , Feminino , Idoso , Ranibizumab/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Injeções Intravítreas , Edema Macular/tratamento farmacológico , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/tratamento farmacológico , Acuidade Visual
3.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38279246

RESUMO

Modifications in DNA repair pathways are recognized as prognostic markers and potential therapeutic targets in various cancers, including non-small cell lung cancer (NSCLC). Overexpression of ERCC1 correlates with poorer prognosis and response to platinum-based chemotherapy. As a result, there is a pressing need to discover new inhibitors of the ERCC1-XPF complex that can potentiate the efficacy of cisplatin in NSCLC. In this study, we developed a structure-based virtual screening strategy targeting the inhibition of ERCC1 and XPF interaction. Analysis of crystal structures and a library of small molecules known to act against the complex highlighted the pivotal role of Phe293 (ERCC1) in maintaining complex stability. This residue was chosen as the primary binding site for virtual screening. Using an optimized docking protocol, we screened compounds from various databases, ultimately identifying more than one hundred potential inhibitors. Their capability to amplify cisplatin-induced cytotoxicity was assessed in NSCLC H1299 cells, which exhibited the highest ERCC1 expression of all the cell lines tested. Of these, 22 compounds emerged as promising enhancers of cisplatin efficacy. Our results underscore the value of pinpointing crucial molecular characteristics in the pursuit of novel modulators of the ERCC1-XPF interaction, which could be combined with cisplatin to treat NSCLC more effectively.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Cisplatino/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Reparo do DNA , Projetos de Pesquisa , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo
4.
J Chem Inf Model ; 63(14): 4447-4457, 2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37132512

RESUMO

Protein aggregation is a complex process, strongly dependent on environmental conditions and highly structurally heterogeneous, both at the final level of fibril structure and intermediate level of oligomerization. Since the first step in aggregation is the formation of a dimer, it is important to clarify how certain properties of the latter (e.g., stability or interface geometry) may play a role in self-association. Here, we report a simple model that represents the dimer's interfacial region by two angles and combine it with a simple computational method to investigate how modulations of the interfacial region occurring on the ns-µs time scale change the dimer's growth mode. To illustrate the proposed methodology, we consider 15 different dimer configurations of the ß2m D76N mutant protein equilibrated with long Molecular Dynamics simulations and identify which interfaces lead to limited and unlimited growth modes, having, therefore, different aggregation profiles. We found that despite the highly dynamic nature of the starting configurations, most polymeric growth modes tend to be conserved within the studied time scale. The proposed methodology performs remarkably well taking into consideration the nonspherical morphology of the ß2m dimers, which exhibit unstructured termini detached from the protein's core, and the relatively weak binding affinities of their interfaces, which are stabilized by nonspecific apolar interactions. The proposed methodology is general and can be applied to any protein for which a dimer structure has been experimentally determined or computationally predicted.


Assuntos
Simulação de Dinâmica Molecular , Agregados Proteicos , Amiloide/química
5.
Eur J Appl Physiol ; 123(10): 2157-2165, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37221340

RESUMO

PURPOSE: Exercise is a critical element for the management of body weight and improvement of quality of life of individuals with obesity. Due to its convenience and accessibility, running is a commonly used exercise modality to meet exercise guidelines. However, the weight-bearing component during high impacts of this exercise modality might limit the participation in exercise and reduce the effectiveness of running-based exercise interventions in individuals with obesity. The hip flexion feedback system (HFFS) assists participants in meeting specific exercise intensities by giving the participant specific increased hip flexion targets while walking on a treadmill. The resulting activity involves walking with increased hip flexion which removes the high impacts of running. The purpose of this study was to compare physiological and biomechanical parameters during an HFFS session and an independent treadmill walking/running session (IND). METHODS: Heart rate, oxygen consumption (VO2), heart rate error, and tibia peak positive accelerations (PPA) were investigated for each condition at 40% and 60% of heart rate reserve exercise intensities. RESULTS: VO2 was higher for IND despite no differences in heart rate. Tibia PPAs were reduced during the HFFS session. Heart rate error was reduced for HFFS during non-steady state exercise. CONCLUSION: While demanding lower energy consumption compared to running, HFFS exercise results in lower tibia PPAs and more accurate monitoring of exercise intensity. HFFS might be a valid exercise alternative for individuals with obesity or individuals that require low-impact forces at the lower limbs.


Assuntos
Marcha , Qualidade de Vida , Humanos , Marcha/fisiologia , Exercício Físico/fisiologia , Caminhada/fisiologia , Obesidade/terapia , Teste de Esforço , Consumo de Oxigênio/fisiologia
6.
Molecules ; 28(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37298742

RESUMO

(S)-Norcoclaurine is synthesized in vivo through a metabolic pathway that ends with (S)-norcoclaurine synthase (NCS). The former constitutes the scaffold for the biosynthesis of all benzylisoquinoline alkaloids (BIAs), including many drugs such as the opiates morphine and codeine and the semi-synthetic opioids oxycodone, hydrocodone, and hydromorphone. Unfortunately, the only source of complex BIAs is the opium poppy, leaving the drug supply dependent on poppy crops. Therefore, the bioproduction of (S)-norcoclaurine in heterologous hosts, such as bacteria or yeast, is an intense area of research nowadays. The efficiency of (S)-norcoclaurine biosynthesis is strongly dependent on the catalytic efficiency of NCS. Therefore, we identified vital NCS rate-enhancing mutations through the rational transition-state macrodipole stabilization method at the Quantum Mechanics/Molecular Mechanics (QM/MM) level. The results are a step forward for obtaining NCS variants able to biosynthesize (S)-norcoclaurine on a large scale.


Assuntos
Alcaloides , Benzilisoquinolinas , Carbono-Nitrogênio Ligases , Papaver , Alcaloides/metabolismo , Carbono-Nitrogênio Ligases/genética , Carbono-Nitrogênio Ligases/metabolismo , Codeína , Papaver/genética , Papaver/metabolismo
7.
Phys Rev Lett ; 128(17): 178102, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35570462

RESUMO

Bacteria often form surface-bound communities, embedded in a self-produced extracellular matrix, called biofilms. Quantitative studies of bioflim growth have typically focused on unconfined expansion above solid or semisolid surfaces, leading to exponential radial growth. This geometry does not accurately reflect the natural or biomedical contexts in which biofilms grow in confined spaces. Here, we consider one of the simplest confined geometries: a biofilm growing laterally in the space between a solid surface and an overlying elastic sheet. A poroelastic framework is utilized to derive the radial growth rate of the biofilm; it reveals an additional self-similar expansion regime, governed by the Poisson's ratio of the matrix, leading to a finite maximum radius, consistent with our experimental observations of growing Bacillus subtilis biofilms confined by polydimethylsiloxane.


Assuntos
Bacillus subtilis , Biofilmes , Matriz Extracelular
8.
J Chem Inf Model ; 62(10): 2550-2560, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35442654

RESUMO

We have designed a protocol combining constant-pH molecular dynamics (CpHMD) simulations with an umbrella sampling (US) scheme (US-CpHMD) to study the mechanism of ADP/ATP transport (import and export) by their inner mitochondrial membrane carrier protein [ADP/ATP carrier (AAC)]. The US scheme helped overcome the limitations of sampling the slow kinetics involved in these substrates' transport, while CpHMD simulations provided an unprecedented realism by correctly capturing the associated protonation changes. The import of anionic substrates along the mitochondrial membrane has a strong energetic disadvantage due to a smaller substrate concentration and an unfavorable membrane potential. These limitations may have created an evolutionary pressure on AAC to develop specific features benefiting the import of ADP. In our work, the potential of mean force profiles showed a clear selectivity in the import of ADP compared to ATP, while in the export, no selectivity was observed. We also observed that AAC sequestered both substrates at longer distances in the import compared to the export process. Furthermore, only in the import process do we observe transient protonation of both substrates when going through the AAC cavity, which is an important advantage to counteract the unfavorable mitochondrial membrane potential. Finally, we observed a substrate-induced disruption of the matrix salt-bridge network, which can promote the conformational transition (from the C- to M-state) required to complete the import process. This work unraveled several important structural features where the complex electrostatic interactions were pivotal to interpreting the protein function and illustrated the potential of applying the US-CpHMD protocol to other transport processes involving membrane proteins.


Assuntos
Mitocôndrias , Simulação de Dinâmica Molecular , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Concentração de Íons de Hidrogênio , Translocases Mitocondriais de ADP e ATP/química , Translocases Mitocondriais de ADP e ATP/metabolismo
9.
Clin Orthop Relat Res ; 480(5): 949-957, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34904964

RESUMO

BACKGROUND: Lateralized reverse shoulder arthroplasty (RSA) has emerged as an attempt to improve on some of the drawbacks of conventional RSA, such as glenoid notching and decrease in ROM. Although this new design is being used in clinical practice, the evidence is mostly limited to case series and has not been systematically reviewed. QUESTIONS/PURPOSES: (1) How much did patient-reported outcome measures (PROMs) and ROM improve among patients who receive a lateralized RSA implant? (2) What proportion of shoulders experience complications, revision surgery, or scapular notching? METHODS: The PubMed and EMBASE databases were searched from database inception to January 31, 2020. We included clinical studies that reported the PROMs and/or ROM of patients with insufficient rotator cuffs undergoing RSA with a lateralized implant. All other types of studies and those including patients with fractures, instability or escape, infection, rheumatologic disease, neurologic disease, or revision surgeries as an indication for RSA were excluded. PROMs and ROM were collected and are reported as mean values and ranges. Complications, revision surgery, and scapular notching are presented as proportions. The percentage of the mean change relative to the minimum clinically important difference (MCID) was calculated using the anchor-based value for each outcome. The Methodological Index for Non-randomized Studies (MINORS) was used to assess study quality. The initial search yielded 678 studies; 61 full-text articles were analyzed according to our eligibility criteria. After a detailed analysis, we included nine studies that evaluated 1670 patients (68% of whom [1130] were women) with a mean age of 71.8 ± 0.6 years. The mean follow-up period was 41.1 ± 5.6 months. The mean MINORS score was 12 ± 4. RESULTS: Active ROM improved for forward flexion (mean change 47° to 82°; MCID 12°), abduction (mean change 43° to 80°; MCID 7°), external rotation (mean change 8° to 39°; MCID 3°), and internal rotation (mean change -2 to 1 points). PROM scores also improved, including the American Shoulder and Elbow Surgeons score (mean change 20 to 50; MCID 20.9 points), Constant score (mean change 28 to 40; MCID 5.7 points), Simple Shoulder Test score (mean change 3 to 7; MCID 2.4 points), and VAS score (mean change -1.8 to -4.9; MCID -1.6 points). The proportion of shoulders with complications ranged from 0% (0 of 44) to 21% (30 of 140), and the proportion of shoulders with scapular notching ranged from 0% (0 of 76) to 29% (41 of 140). The proportion of patients undergoing revision ranged from 0% (0 of 44) to 13% (10 of 76) at short-term follow-up. CONCLUSION: Lateralized RSA is a reasonable alternative to medialized implants for patients with rotator cuff insufficiency because it might reduce the likelihood of scapular notching without apparently compromising PROMs or ROM. More studies are required to determine whether there is a direct correlation between the amount of lateralization and PROMs or ROM.


Assuntos
Artroplastia do Ombro , Articulação do Ombro , Prótese de Ombro , Idoso , Artroplastia do Ombro/efeitos adversos , Feminino , Humanos , Masculino , Amplitude de Movimento Articular , Estudos Retrospectivos , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/cirurgia , Resultado do Tratamento
10.
Arch Toxicol ; 95(2): 375-393, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33097969

RESUMO

Areca nut (AN) is consumed by more than 600 million of individuals, particularly in some regions of South Asia, East Africa, and tropical Pacific, being classified as carcinogenic to humans. The most popular way of exposure consists of chewing a mixture of AN with betel leaf, slaked lime, and other ingredients that may also contain tobacco named betel quid (BQ). Arecoline is the principal active compound of AN, and, therefore, has been systematically studied over the years in several in vitro and in vivo genotoxicity endpoints. However, much of this information is dispersed, justifying the interest of an updated and comprehensive review article on this topic. In this sense, it is thus pertinent to describe and integrate the genetic toxicology data available as well as to address key toxicokinetics aspects of arecoline. This review also provides information on the effects induced by arecoline metabolites and related compounds, including other major AN alkaloids and nitrosation derivatives. The complexity of the chemicals involved renders this issue a challenge in genetic toxicology. Overall, positive results in several endpoints have been reported, some of them suggesting a key role for arecoline metabolites. Nevertheless, some negative genotoxicity findings for this alkaloid in short-term assays have also been reported in the literature. Finally, this article also collates information on the potential mechanisms of arecoline-induced genotoxicity, and suggests further approaches to tackle this important toxicological issue.


Assuntos
Areca/toxicidade , Arecolina/toxicidade , Carcinógenos/toxicidade , Mutagênicos/toxicidade , Alcaloides , Areca/química , Dano ao DNA , Humanos , Redes e Vias Metabólicas , Mutação , Toxicocinética
11.
Orthod Craniofac Res ; 24 Suppl 2: 6-15, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34270881

RESUMO

OBJECTIVE: This scoping review aims to determine the applications of Artificial Intelligence (AI) that are extensively employed in the field of Orthodontics, to evaluate its benefits, and to discuss its potential implications in this speciality. Recent decades have witnessed enormous changes in our profession. The arrival of new and more aesthetic options in orthodontic treatment, the transition to a fully digital workflow, the emergence of temporary anchorage devices and new imaging methods all provide both patients and professionals with a new focus in orthodontic care. MATERIALS AND METHODS: This review was performed following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. The electronic literature search was performed through MEDLINE/PubMed, Scopus, Web of Science, Cochrane and IEEE Xplore databases with a 11-year time restriction: January 2010 till March 2021. No additional manual searches were performed. RESULTS: The electronic literature search initially returned 311 records, and 115 after removing duplicate references. Finally, the application of the inclusion criteria resulted in 17 eligible publications in the qualitative synthesis review. CONCLUSION: The analysed studies demonstrated that Convolution Neural Networks can be used for the automatic detection of anatomical reference points on radiological images. In the growth and development research area, the Cervical Vertebral Maturation stage can be determined using an Artificial Neural Network model and obtain the same results as expert human observers. AI technology can also improve the diagnostic accuracy for orthodontic treatments, thereby helping the orthodontist work more accurately and efficiently.


Assuntos
Inteligência Artificial , Ortodontia , Estética Dentária , Humanos
12.
Int J Mol Sci ; 22(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34884877

RESUMO

Doxorubicin (Dox) is one of the most widely used treatments for breast cancer, although limited by the well-documented cardiotoxicity and other off-target effects. Mesenchymal stem cell (MSC) secretome has shown immunomodulatory and regenerative properties, further potentiated under 3D conditions. This work aimed to uncover the effect of the MSC-derived secretome from 3D (CM3D) or 2D (CM2D) cultures, in human malignant breast cells (MDA-MB-231), non-tumor breast epithelial cells (MCF10A) and differentiated AC16 cardiomyocytes, co-treated with Dox. A comprehensive proteomic analysis of CM3D/CM2D was also performed to unravel the underlying mechanism. CM3D/CM2D co-incubation with Dox revealed no significant differences in MDA-MB-231 viability when compared to Dox alone, whereas MCF10A and AC16 viability was consistently improved in Dox+CM3D-treated cells. Moreover, neither CM2D nor CM3D affected Dox anti-migratory and anti-invasive effects in MDA-MB-231. Notably, Ge-LC-MS/MS proteomic analysis revealed that CM3D displayed protective features that might be linked to the regulation of cell proliferation (CAPN1, CST1, LAMC2, RANBP3), migration (CCN3, MMP8, PDCD5), invasion (TIMP1/2), oxidative stress (COX6B1, AIFM1, CD9, GSR) and inflammation (CCN3, ANXA5, CDH13, GDF15). Overall, CM3D decreased Dox-induced cytotoxicity in non-tumor cells, without compromising Dox chemotherapeutic profile in malignant cells, suggesting its potential use as a chemotherapy adjuvant to reduce off-target side effects.


Assuntos
Neoplasias da Mama/terapia , Doxorrubicina/farmacologia , Imunomodulação , Células-Tronco Mesenquimais/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Secretoma , Neoplasias da Mama/tratamento farmacológico , Cardiotoxicidade/prevenção & controle , Linhagem Celular , Linhagem Celular Tumoral , Terapia Combinada , Doxorrubicina/uso terapêutico , Feminino , Humanos , Estresse Oxidativo
13.
Int J Mol Sci ; 21(11)2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32503263

RESUMO

The need for competent in vitro liver models for toxicological assessment persists. The differentiation of stem cells into hepatocyte-like cells (HLC) has been adopted due to its human origin and availability. Our aim was to study the usefulness of an in vitro 3D model of mesenchymal stem cell-derived HLCs. 3D spheroids (3D-HLC) or monolayer (2D-HLC) cultures of HLCs were treated with the hepatotoxic drug nevirapine (NVP) for 3 and 10 days followed by analyses of Phase I and II metabolites, biotransformation enzymes and drug transporters involved in NVP disposition. To ascertain the toxic effects of NVP and its major metabolites, the changes in the glutathione net flux were also investigated. Phase I enzymes were induced in both systems yielding all known correspondent NVP metabolites. However, 3D-HLCs showed higher biocompetence in producing Phase II NVP metabolites and upregulating Phase II enzymes and MRP7. Accordingly, NVP-exposure led to decreased glutathione availability and alterations in the intracellular dynamics disfavoring free reduced glutathione and glutathionylated protein pools. Overall, these results demonstrate the adequacy of the 3D-HLC model for studying the bioactivation/metabolism of NVP representing a further step to unveil toxicity mechanisms associated with glutathione net flux changes.


Assuntos
Biotransformação , Glutationa/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Nevirapina/farmacocinética , Diferenciação Celular , Linhagem Celular , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Células-Tronco Mesenquimais/citologia , Solventes , Esferoides Celulares , Cordão Umbilical/citologia , Xenobióticos/farmacologia
14.
Drug Metab Rev ; 51(3): 293-313, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31124380

RESUMO

Bupropion is an atypical antidepressant of the aminoketone group, structurally related to cathinone, associated with a wide interindividual variability. An extensive pharmacokinetic and pharmacodynamic review of bupropion was performed, also focusing on chemical, pharmacological, toxicological, clinical and forensic aspects of this drug without a limiting period. Bupropion is a chiral, basic, highly lipophilic drug, clinically used as racemate that undergoes extensive stereoselective metabolism. Its major active metabolites, hydroxybupropion, threohydrobupropion, and erythrohydrobupropion reach higher plasma concentrations than bupropion. Bupropion exerts its effects mainly by inhibiting dopamine and norepinephrine reuptake and by blocking several nicotinic receptors. Recent reports highlight recreational use of bupropion via intranasal insufflation and intravenous use. Seizures, insomnia, agitation, headache, dry mouth, and nausea are some of the reported adverse effects. Neurologic effects are major signs of intoxication that should be carefully managed. Finally, the characterization of the polymorphic enzymes involved in the metabolism of bupropion is essential to understand factors that may influence the interindividual and intraindividual variability in bupropion metabolite exposure, including the evaluation of potential drug-drug interactions and pharmacogenetic implications.


Assuntos
Bupropiona/farmacologia , Bupropiona/farmacocinética , Animais , Antidepressivos de Segunda Geração/efeitos adversos , Antidepressivos de Segunda Geração/química , Antidepressivos de Segunda Geração/farmacocinética , Antidepressivos de Segunda Geração/farmacologia , Bupropiona/efeitos adversos , Bupropiona/química , Toxicologia Forense , Humanos
15.
Proc Natl Acad Sci U S A ; 113(23): 6532-7, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27222583

RESUMO

Bacteria form surface-attached communities, known as biofilms, which are central to bacterial biology and how they affect us. Although surface-attached bacteria often experience strong chemical gradients, it remains unclear whether single cells can effectively perform chemotaxis on surfaces. Here we use microfluidic chemical gradients and massively parallel automated tracking to study the behavior of the pathogen Pseudomonas aeruginosa during early biofilm development. We show that individual cells can efficiently move toward chemoattractants using pili-based "twitching" motility and the Chp chemosensory system. Moreover, we discovered the behavioral mechanism underlying this surface chemotaxis: Cells reverse direction more frequently when moving away from chemoattractant sources. These corrective maneuvers are triggered rapidly, typically before a wayward cell has ventured a fraction of a micron. Our work shows that single bacteria can direct their motion with submicron precision and reveals the hidden potential for chemotaxis within bacterial biofilms.


Assuntos
Quimiotaxia , Pseudomonas aeruginosa/fisiologia , Fenômenos Fisiológicos Bacterianos , Biofilmes , Bioensaio , Dimetil Sulfóxido/química , Fímbrias Bacterianas/fisiologia , Dispositivos Lab-On-A-Chip
16.
Int J Mol Sci ; 20(20)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618886

RESUMO

The role of metalloproteinases (MMPs) on the migration and invasion of cancer cells has been correlated with tumor aggressiveness, namely with the up-regulation of MMP-2 and 9. Herein, two pyridine-containing macrocyclic compounds, [15]pyN5 and [16]pyN5, were synthesized, chemically characterized and evaluated as potential MMP inhibitors for breast cancer therapy using 3D and 2D cellular models. [15]pyN5 and [16]pyN5 (5-20 µM) showed a marked inhibition of MMPs activity (100% at concentrations ≥ 7.5 µM) when compared to ARP-100, a known MMP inhibitor. The inhibitory activity of [15]pyN5 and [16]pyN5 was further supported through in silico docking studies using Goldscore and ChemPLP scoring functions. Moreover, although no significant differences were observed in the invasion studies in the presence of all MMPs inhibitors, cell migration was significantly inhibited by both pyridine-containing macrocycles at concentrations above 5 µM in 2D cells (p < 0.05). In spheroids, the same effect was observed, but only with [16]pyN5 at 20 µM and ARP-100 at 40 µM. Overall, [15]pyN5 and [16]pyN5 led to impaired breast cancer cell migration and revealed to be potential inhibitors of MMPs 2 and 9.


Assuntos
Compostos Macrocíclicos/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/farmacologia , Piridinas/farmacologia , Sítios de Ligação , Catálise , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Compostos Macrocíclicos/química , Metaloproteinase 2 da Matriz/química , Metaloproteinase 9 da Matriz/química , Inibidores de Metaloproteinases de Matriz/química , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Piridinas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Zinco/química
17.
PLoS Biol ; 13(7): e1002191, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26158271

RESUMO

Bacteria form dense surface-associated communities known as biofilms that are central to their persistence and how they affect us. Biofilm formation is commonly viewed as a cooperative enterprise, where strains and species work together for a common goal. Here we explore an alternative model: biofilm formation is a response to ecological competition. We co-cultured a diverse collection of natural isolates of the opportunistic pathogen Pseudomonas aeruginosa and studied the effect on biofilm formation. We show that strain mixing reliably increases biofilm formation compared to unmixed conditions. Importantly, strain mixing leads to strong competition: one strain dominates and largely excludes the other from the biofilm. Furthermore, we show that pyocins, narrow-spectrum antibiotics made by other P. aeruginosa strains, can stimulate biofilm formation by increasing the attachment of cells. Side-by-side comparisons using microfluidic assays suggest that the increase in biofilm occurs due to a general response to cellular damage: a comparable biofilm response occurs for pyocins that disrupt membranes as for commercial antibiotics that damage DNA, inhibit protein synthesis or transcription. Our data show that bacteria increase biofilm formation in response to ecological competition that is detected by antibiotic stress. This is inconsistent with the idea that sub-lethal concentrations of antibiotics are cooperative signals that coordinate microbial communities, as is often concluded. Instead, our work is consistent with competition sensing where low-levels of antibiotics are used to detect and respond to the competing genotypes that produce them.


Assuntos
Antibiose , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/crescimento & desenvolvimento , Piocinas/farmacologia , Antibacterianos , Biofilmes/efeitos dos fármacos , Técnicas de Cocultura , Microfluídica
18.
Somatosens Mot Res ; 35(2): 124-130, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-30012020

RESUMO

After a stroke in middle cerebral artery territory, there is a high probability of dysfunction of the ventromedial pathways, mainly related with postural control mechanisms such as the anticipatory postural adjustments (APAs). According to neuroanatomical knowledge, these pathways have a predominant ipsilesional disposition, which justifies a bilateral postural control dysfunction, often neglected in rehabilitation. In order to assess this bilateral postural control dysfunction, electromyography activity was assessed in eight post-stroke and 10 healthy individuals in the anterior deltoids, the superior and lower trapezius, and the latissimus dorsi as they reached for a bottle with both upper limbs separately at a self-selected velocity and fast velocity while standing associated with trunk kinematics analysis. Through this analysis it was possible to compare the timing of APAs in scapular muscles between sides in post-stroke and with healthy individuals, and to verify if there is a relation between the timing and the displacement of the trunk in the temporal window of the APAs. Indeed, post-stroke individuals show a delayed activation of APAs on scapular girdle muscles on both ipsilesional and contralesional sides, which were not reflected in the trunk displacement.


Assuntos
Transtornos dos Movimentos/etiologia , Movimento/fisiologia , Postura/fisiologia , Amplitude de Movimento Articular/fisiologia , Acidente Vascular Cerebral/complicações , Idoso , Eletromiografia , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Equilíbrio Postural/fisiologia , Tempo de Reação/fisiologia , Estatísticas não Paramétricas , Inquéritos e Questionários , Extremidade Superior/fisiopatologia
19.
Arch Toxicol ; 92(10): 2987-3006, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30116851

RESUMO

Cocaine is one of the most widely consumed psychoactive substances and has been recognized as a major public health concern for many years. While several aspects of the toxicology of cocaine have been thoroughly described in the literature, namely its effects on different target organs, other toxicological features should not be disregarded. In this perspective, the in vitro and in vivo genotoxic effects of cocaine, along with the genotoxicity data from human exposure, especially in the context of "crack" smoking, were reviewed. Some concerns regarding (1) the chronic abuse and forms of cocaine, (2) the role of metabolism and (3) the mode of action of cocaine were discussed. The major limitations of the experimental and human studies available were also addressed and some research gaps in this field identified. Overall, although the genotoxicity of cocaine is still a matter of discussion, this psychoactive substance exhibits a genotoxic potential that should be further considered.


Assuntos
Cocaína/toxicidade , Drogas Ilícitas/toxicidade , Testes de Mutagenicidade/métodos , Animais , Organismos Aquáticos/efeitos dos fármacos , Carcinógenos/toxicidade , Segregação de Cromossomos/efeitos dos fármacos , Cocaína/química , Cocaína/farmacocinética , Humanos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Roedores , Transtornos Relacionados ao Uso de Substâncias/genética , Poluentes Químicos da Água/toxicidade
20.
Ophthalmologica ; 240(1): 29-36, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29734180

RESUMO

PURPOSE: To investigate the influence of the vitreoretinal interface on the outcomes of different ranibizumab regimens for exudative age-related macular degeneration. METHODS: We conducted a retrospective subanalysis of 2 prospective clinical trials. Patients were treated with ranibizumab for 12 months according to 3 different regimens: pro-re-nata (PRN), treat and extend (T&E), and monthly. Vitreoretinal interface was assessed for absence (group ON) or presence (group OFF) of posterior vitreous detachment (PVD). RESULTS: We included 64 eyes from 64 patients. Visual improvement was poorer for group ON (0.3 ± 10.7 letters) than for group OFF (9.2 ± 13.3; p = 0.007). A significant difference in letters of improvement between groups was observed in the PRN cohort (ON: -5.0 ± 12.9; OFF: 11.4 ± 11.9; p = 0.003), but not in the cohorts with monthly (ON: 5.7 ± 7.8; OFF: 7.9 ± 15.2; p = 0.735) or T&E (ON: 4.3 ± 4.3; OFF: 7.8 ± 11.1; p = 0.424) treatment. CONCLUSION: The negative impact of absence of PVD is regimen dependent, with monthly dosing providing similar outcomes to PVD patients. In the absence of PVD (group ON), PRN should be avoided, and T&E might be an alternative.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Ranibizumab/uso terapêutico , Retina/fisiopatologia , Corpo Vítreo/fisiopatologia , Descolamento do Vítreo/fisiopatologia , Degeneração Macular Exsudativa/tratamento farmacológico , Idoso , Exsudatos e Transudatos , Feminino , Adesões Focais/fisiologia , Humanos , Injeções Intravítreas , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia , Degeneração Macular Exsudativa/diagnóstico por imagem , Degeneração Macular Exsudativa/fisiopatologia
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