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1.
J Immunol ; 211(5): 721-726, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37486206

RESUMO

CTL differentiation is controlled by the crosstalk of various transcription factors and epigenetic modulators. Uncovering this process is fundamental to improving immunotherapy and designing novel therapeutic approaches. In this study, we show that polycomb repressive complex 1 subunit chromobox (Cbx)4 favors effector CTL differentiation in a murine model. Cbx4 deficiency in CTLs induced a transcriptional signature of memory cells and increased the memory CTL population during acute viral infection. It has previously been shown that besides binding to H3K27me3 through its chromodomain, Cbx4 functions as a small ubiquitin-like modifier (SUMO) E3 ligase in a SUMO-interacting motifs (SIM)-dependent way. Overexpression of Cbx4 mutants in distinct domains showed that this protein regulates CTL differentiation primarily in an SIM-dependent way and partially through its chromodomain. Our data suggest a novel role of a polycomb group protein Cbx4 controlling CTL differentiation and indicated SUMOylation as a key molecular mechanism connected to chromatin modification in this process.


Assuntos
Complexo Repressor Polycomb 1 , Ubiquitina-Proteína Ligases , Animais , Camundongos , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 1/metabolismo , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
2.
Environ Toxicol ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39329436

RESUMO

Zika virus (ZIKV) infection during pregnancy can lead to a set of congenital malformations known as Congenital ZIKV syndrome (CZS), whose main feature is microcephaly. The geographic distribution of CZS in Brazil during the 2015-2017 outbreak was asymmetrical, with a higher prevalence in the Northeast and Central-West regions of the country, despite the ubiquitous distribution of the vector Aedes aegypti, indicating that environmental factors could influence ZIKV vertical transmission and/or severity. Here we investigate the involvement of the most used agrochemicals in Brazil with CZS. First, we exposed human neuroblastoma SK-N-AS cells to the 15 frequently used agrochemical molecules or derivative metabolites able to cross the blood-brain barrier. We found that a derived metabolite from a widely used herbicide in the Central-West region, 2,4-dichlorophenoxyacetic acid (2,4D), exacerbates ZIKV neurotoxic effects in vitro. We validate this observation by demonstrating vertical transmission leading to microcephaly in the offspring of immunocompetent C57BL/6J mice exposed to water contaminated with 0.025 mg/L of 2,4D. Newborn mice whose dams were exposed to 2,4D and infected with ZIKV presented a smaller brain area and cortical plate size compared to the control. Also, embryos from animals facing the co-insult of ZIKV and 2,4D exposition presented higher Caspase 3 positive cells in the cortex, fewer CTIP2+ neurons and proliferative cells at the ventricular zone, and a higher viral load. This phenotype is followed by placental alterations, such as vessel congestion, and apoptosis in the labyrinth and decidua. We also observed a mild spatial correlation between CZS prevalence and 2,4D use in Brazil's North and Central-West regions, with R2 = 0.4 and 0.46, respectively. Our results suggest that 2,4D exposition facilitates maternal vertical transmission of ZIKV, exacerbating CZS, possibly contributing to the high prevalence of this syndrome in Brazil's Central-West region compared to other regions.

3.
Br J Clin Pharmacol ; 89(10): 3175-3194, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37293836

RESUMO

AIMS: To develop paediatric physiologically based pharmacokinetic modelling (PBPK) models of semaglutide to estimate the pharmacokinetic profile for subcutaneous injections in children and adolescents with healthy and obese body weights. METHODS: Pharmacokinetic modelling and simulations of semaglutide subcutaneous injections were performed using the Transdermal Compartmental Absorption & Transit model implemented in GastroPlus v.9.5 modules. A PBPK model of semaglutide was developed and verified in the adult population, by comparing the simulated plasma exposure with the observed data, and further scaled to the paediatric populations with normal and obese body weight. RESULTS: The semaglutide PBPK model was successfully developed in adults and scaled to the paediatric population. Our paediatric PBPK simulations indicated a significant increase in maximum plasma concentrations for the 10-14 years' paediatric population with healthy body weights, which was higher than the observed values in adults at the reference dose. Since gastrointestinal adverse events are related to increased semaglutide concentrations, peak concentrations outside the target range may represent a safety risk for this paediatric age group. Besides, paediatric PBPK models indicated that body weight was inversely related to semaglutide maximum plasma concentration, corroborating the consensus on the influence of body weight on semaglutide PK in adults. CONCLUSION: Paediatric PBPK was successfully achieved using a top-down approach and drug-related parameters. The development of unprecedented PBPK models will support paediatric clinical therapy for applying aid-safe dosing regimens for the paediatric population in diabetes treatment.


Assuntos
Modelos Biológicos , Obesidade , Adulto , Criança , Humanos , Adolescente , Peso Corporal , Obesidade/tratamento farmacológico , Simulação por Computador
4.
J Cell Biochem ; 123(7): 1259-1277, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35644025

RESUMO

Alzheimer's disease (AD) is the leading cause of dementia worldwide. Despite causing great social and economic impact, there is currently no cure for AD. The most effective therapy to manage AD symptoms is based on acetylcholinesterase inhibitors (AChEi), from which rivastigmine presented numerous benefits. However, mutations in AChE, which affect approximately 5% of the population, can modify protein structure and function, changing the individual response to Alzheimer's treatment. In this study, we performed computer simulations of AChE wild type and variants R34Q, P135A, V333E, and H353N, identified by one or more genome-wide association studies, to evaluate their effects on protein structure and interaction with rivastigmine. The functional effects of AChE variants were predicted using eight machine learning algorithms, while the evolutionary conservation of AChE residues was analyzed using the ConSurf server. Autodock4.2.6 was used to predict the binding modes for the hAChE-rivastigmine complex, which is still unknown. Molecular dynamics (MD) simulations were performed in triplicates for the AChE wild type and mutants using the GROMACS packages. Among the analyzed variants, P135A was classified as deleterious by all the functional prediction algorithms, in addition to occurring at highly conserved positions, which may have harmful consequences on protein function. The molecular docking results suggested that rivastigmine interacts with hAChE at the upper active-site gorge, which was further confirmed by MD simulations. Our MD findings also suggested that the complex hAChE-rivastigmine remains stable over time. The essential dynamics revealed flexibility alterations at the active-site gorge upon mutations P135A, V333E, and H353N, which may lead to strong and nonintuitive consequences to hAChE binding. Nonetheless, similar binding affinities were registered in the MMPBSA analysis for the hAChE wild type and variants when complexed to rivastigmine. Finally, our findings indicated that the rivastigmine binding to hAChE is an energetically favorable process mainly driven by negatively charged amino acids.


Assuntos
Acetilcolinesterase , Doença de Alzheimer , Acetilcolinesterase/química , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Estudo de Associação Genômica Ampla , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Rivastigmina/uso terapêutico
5.
An Acad Bras Cienc ; 94(suppl 3): e20211287, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36197362

RESUMO

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are the latest class of drugs approved to treat type 2 DM (T2DM). Although adverse effects are often caused by a metabolite rather than the drug itself, only the safety assessment of disproportionate drug metabolites is usually performed, which is of particular concern for drugs of chronic use, such as SGLT2i. Bearing this in mind, in silico tools are efficient strategies to reveal the risk assessment of metabolites, being endorsed by many regulatory agencies. Thereby, the goal of this study was to apply in silico methods to provide the metabolites toxicity assessment of the SGLT2i. Toxicological assessment from SGLT2i metabolites retrieved from the literature was estimated using the structure and/or statistical-based alert implemented in DataWarrior and ADMET predictorTM softwares. The drugs and their metabolites displayed no mutagenic, tumorigenic or cardiotoxic risks. Still, M1-2 and M3-1 were recognized as potential hepatotoxic compounds and M1-2, M1-3, M3-1, M3-2, M3-3 and M4-3, were estimated to have very toxic LD50 values in rats. All SGLT2i and the metabolites M3-4, M4-1 and M4-2, were predicted to have reproductive toxicity. These results support the awareness that metabolites may be potential mediators of drug-induced toxicities of the therapeutic agents.


Assuntos
Inibidores do Transportador 2 de Sódio-Glicose , Animais , Ratos , Medição de Risco , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/toxicidade
6.
J Environ Manage ; 286: 112114, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33618323

RESUMO

The biological treatment of mine drainage (MD) using sulfate-reducing bacteria (SRB) is a technology in growing exploitation. The use of by-products as sources of electrons can make this treatment more environmentally and economically advantageous. However, the high chemical oxygen demand (COD) and the presence of recalcitrant molecules can lead to the accumulation of metabolic intermediates that acidify the system, thus interrupting the treatment. Besides, the adaptation of the inoculum to the establishment of sulfidogenesis with MD and by-product may be slow. This study aimed to investigate prompt adaptation and operation strategies that do not require additives to enable the sulfidogenic process to occur while maintaining a pH close to neutrality. The sources of electrons tested were trub (brewery residue) and crude glycerol - CG (residue from the biodiesel production). The inoculum from a methanogenic reactor was stored with a real MD for a month. The adapted inoculum was applied in a batch reactor for 168 h of hydraulic detention time, and promoted 75.8 ± 4.3% of sulfate removal from an MD with 3756.4 ± 258 mg.L-1 of sulfate using CG in a COD/SO42- ratio of 3 ratio. With higher initial substrate concentrations, acidification occurred and the treatment was interrupted. Using trub instead of CG, the acidification occurred at a COD/SO42- ratio of 3. Acidification was prevented and the best efficiencies in sulfate removal were obtained when the amount of substrate corresponding to COD/SO42- ratio of 3 was fractioned into equal parts and added over six days in the CG reactor. It was achieved 94.15 ± 1.76% of sulfate removal. With trub, the same procedure in which this COD was divided into seven parts, and resulted in a sulfate removal of 88.49 ± 1.02%. The removal of metals and metalloids were greater than 94.5% in all the systems in which the substrate supply was made fractionally, and the effluent generated presented alkalinity between 3370 and 4242 mg CaCO3.L-1, and pH between 6.8 and 7. The method of adaptation and operation applied allowed the realization of a MD treatment with quick establishment of sulfidogenesis and without the use of neutralizing additives. Finally, the effluent presented characteristics considered favorable for a later stage of post-treatment of the effluent with methane generation.


Assuntos
Reatores Biológicos , Sulfatos , Análise da Demanda Biológica de Oxigênio , Metais , Metano , Eliminação de Resíduos Líquidos
7.
J Cell Biochem ; 121(2): 1114-1125, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31478225

RESUMO

Infectious diseases are serious public health problems, affecting a large portion of the world's population. A molecule that plays a key role in pathogenic organisms is trehalose and recently has been an interest in the metabolism of this molecule for drug development. The trehalose-6-phosphate synthase (TPS1) is an enzyme responsible for the biosynthesis of trehalose-6-phosphate (T6P) in the TPS1/TPS2 pathway, which results in the formation of trehalose. Studies carried out by our group demonstrated the inhibitory capacity of T6P in the TPS1 enzyme from Saccharomyces cerevisiae, preventing the synthesis of trehalose. By in silico techniques, we compiled sequences and experimentally determined structures of TPS1. Sequence alignments and molecular modeling were performed. The generated structures were submitted in validation of algorithms, aligned structurally and analyzed evolutionarily. Molecular docking methodology was applied to analyze the interaction between T6P and TPS1 and ADMET properties of T6P were analyzed. The results demonstrated the models created presented sequence and structural similarities with experimentally determined structures. With the molecular docking, a cavity in the protein surface was identified and the molecule T6P was interacting with the residues TYR-40, ALA-41, MET-42, and PHE-372, indicating the possible uncompetitive inhibition mechanism provided by this ligand, which can be useful in directing the molecular design of inhibitors. In ADMET analyses, T6P had acceptable risk values compared with other compounds from World Drug Index. Therefore, these results may present a promising strategy to explore to develop a broad-spectrum antibiotic of this specific target with selectivity, potency, and reduced side effects, leading to a new way to treat infectious diseases like tuberculosis and candidiasis.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/metabolismo , Glucosiltransferases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Fosfatos Açúcares/metabolismo , Trealose/análogos & derivados , Simulação por Computador , Inibidores Enzimáticos/química , Glucosiltransferases/química , Modelos Moleculares , Simulação de Acoplamento Molecular , Conformação Proteica , Proteínas de Saccharomyces cerevisiae/química , Fosfatos Açúcares/química , Trealose/química , Trealose/metabolismo
8.
BMC Pediatr ; 20(1): 2, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900120

RESUMO

BACKGROUND: Early diagnosis and treatment are improving significantly the quality of life of patients with cystic fibrosis (CF). This recessive disease is caused by a great variability of mutations in the CF transmembrane conductance (CFTR) gene, whose spectrum and frequency can be different across populations. METHODS: We performed a retrospective cross-sectional study of CF patients from the island of São Miguel (Azores, Portugal) through a clinical, genealogical, genetic and epidemiological investigation. The clinical course of patients was analyzed as a whole and according to their genotype. RESULTS: We identified 14 CF patients within a 23-year period, corresponding to a cumulative incidence of 1:3012 births, being three of them born from consanguineous unions. Genetic analysis revealed three CFTR genotypes: p.[Ser4Ter];[Gln1100Pro] was present in one patient with a less severe phenotype (1/14); c.[120del23];p.[Phe508del], a very rare one (2/14); and p.[Phe508del];[Phe508del] in the remaining patients (11/14). Clinically, respiratory infections (8/14) and growth failure (6/14) were the most common initial manifestations. All patients presented pancreatic dysfunction, with 21.4 and 100% of them showing endocrine and exocrine insufficiency, respectively. As expected, patients with severe phenotype were homozygous for p.Phe508del and had the lowest value of body mass index. CONCLUSIONS: The present study demonstrated that São Miguel Island has an increased incidence of CF when compared to recent Portuguese data (1:7500 live births). It also allowed a comprehensive overview of CF in São Miguel, improving medical practice along with genetic counselling and creating opportunities for genotype-targeted therapies.


Assuntos
Fibrose Cística , Açores , Estudos Transversais , Fibrose Cística/diagnóstico , Fibrose Cística/epidemiologia , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Genótipo , Humanos , Mutação , Portugal/epidemiologia , Qualidade de Vida , Estudos Retrospectivos
9.
Biomed Chromatogr ; 34(7): e4832, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32190911

RESUMO

Injectable solutions containing epinephrine (EPI) and norepinephrine (NE) are not stable, and their degradation is favored mainly by the oxidation of catechol moiety. As studies of these drugs under forced degradation conditions are scarce, herein, we report the identification of their degradation products (DP) in anesthetic formulations by the development of stability-indicating HPLC method. Finally, the risk assessment of the major degradation products was evaluated using in silico toxicity approach. HPLC method was developed to obtain a higher selectivity allowing adequate elution for both drugs and their DPs. The optimized conditions were developed using a C18 HPLC column, sodium 1-octanesulfonate, and methanol (80:20, v/v) as mobile phase, with a flow rate of 1.5 mL/min, UV detection at 199 nm. The analysis of standard solutions with these modifications resulted in greater retention time for EPI and NE, which allow the separation of these drugs from their respective DPs. Then, five DPs were identified and analyzed by in silico studies. Most of the DPs showed important alerts as hepatotoxicity and mutagenicity. To the best of our acknowledgment, this is the first report of a stability-indicating HPLC method that can be used with formulations containing catecholamines.


Assuntos
Anestésicos , Cromatografia Líquida de Alta Pressão/métodos , Epinefrina , Norepinefrina , Anestesia Dentária , Anestésicos/análise , Anestésicos/química , Anestésicos/toxicidade , Animais , Simulação por Computador , Estabilidade de Medicamentos , Epinefrina/análise , Epinefrina/química , Epinefrina/toxicidade , Limite de Detecção , Modelos Lineares , Camundongos , Norepinefrina/análise , Norepinefrina/química , Norepinefrina/toxicidade , Ratos , Reprodutibilidade dos Testes
10.
An Acad Bras Cienc ; 92(2): e20191445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785428

RESUMO

Sildenafil is a potent selective inhibitor of phosphosdiesterase-5 previously used in erectile dysfunction and subsequently approved in 2005 for pulmonary arterial hypertension treatment. Since oral administration of sildenafil shows pharmacokinetic problems with mean absolute bioavailability of 41%, the goal of this work was to develop a novel sildenafil self-emulsifying drug delivery system (SEDDS) for oral absorption improvement and management of dosage. One pharmaceutical solution and four SEDDS containing sildenafil were successfully obtained and SEDDS formed O/W nanoemulsion with droplet size less than 300 nm. The stability studies evidenced that the SEDDS containing 3.3% w/w of sildenafil yielded the best results. The safety of 2-pyrrolidone/isobutanol in oral formulations was assessed in mice and no lethality was achieved in the placebo groups with LD50 of 490 mg/Kg for SEDDS II-3.3, suggesting it as a safe excipient for humans. Therewithal, in silico studies using PBPK models provided the pharmacokinetic profile of sildenafil SEDDS. Subsequently, in silico evaluation indicated that the sildenafil SEDDS droplet size influenced its bioavailability, enhancing absorption, assuring a good pharmacokinetic profile. These findings suggest that the formulations developed here presented the potential to enhance drug oral absorption with the possibility to control drug dosage as they are liquid pharmaceutical formulations.


Assuntos
Hipertensão Arterial Pulmonar , Animais , Química Farmacêutica , Sistemas de Liberação de Medicamentos , Emulsões , Humanos , Camundongos , Citrato de Sildenafila
11.
Bioorg Med Chem Lett ; 27(2): 314-318, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27914800

RESUMO

Human kallikrein 1 (KLK1) is the most extensively studied member of this family and plays a major role in inflammation processes. From Ugi multicomponent reactions, isomannide-based peptidomimetic 10 and 13 where synthesized and showed low micromolar values of IC50 for KLK1 The most active compound (10) presented competitive mechanism, with three structural modifications important to interact with active site residues which corroborates its KLK1 inhibition. Finally, the most active compound also showed good ADMET profile, which indicates compound 10 as a potential hit in the search for new KLK1 inhibitors with low side effects.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Calicreínas/antagonistas & inibidores , Peptidomiméticos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Calicreínas/metabolismo , Modelos Moleculares , Estrutura Molecular , Peptidomiméticos/síntese química , Peptidomiméticos/química , Relação Estrutura-Atividade
12.
Mem Inst Oswaldo Cruz ; 112(4): 299-308, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28327793

RESUMO

BACKGROUND: Malaria persists as a major public health problem. Atovaquone is a drug that inhibits the respiratory chain of Plasmodium falciparum, but with serious limitations like known resistance, low bioavailability and high plasma protein binding. OBJECTIVES: The aim of this work was to perform molecular modelling studies of 2-hydroxy-1,4-naphthoquinones analogues of atovaquone on the Qo site of P. falciparum cytochrome bc1 complex (Pfbc1) to suggest structural modifications that could improve their antimalarial activity. METHODS: We have built the homology model of the cytochrome b (CYB) and Rieske iron-sulfur protein (ISP) subunits from Pfbc1 and performed the molecular docking of 41 2-hydroxy-1,4-naphthoquinones with known in vitro antimalarial activity and predicted to act on this target. FINDINGS: Results suggest that large hydrophobic R2 substituents may be important for filling the deep hydrophobic Qo site pocket. Moreover, our analysis indicates that the H-donor 2-hydroxyl group may not be crucial for efficient binding and inhibition of Pfbc1 by these atovaquone analogues. The C1 carbonyl group (H-acceptor) is more frequently involved in the important hydrogen bonding interaction with His152 of the Rieske ISP subunit. MAIN CONCLUSIONS: Additional interactions involving residues such as Ile258 and residues required for efficient catalysis (e.g., Glu261) could be explored in drug design to avoid development of drug resistance by the parasite.


Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Complexo III da Cadeia de Transporte de Elétrons/química , Naftoquinonas/química , Naftoquinonas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Análise de Sequência de Proteína
13.
J Environ Manage ; 192: 224-233, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28171834

RESUMO

Arsenic is a semi-metal element that can enter in water bodies and drinking water supplies from natural deposits and from mining, industrial and agricultural practices. The aim of the present work was to propose an alternative process for removing As from water, based on adsorption on a brown seaweed (Sargassum muticum), after a simple and inexpensive treatment: coating with iron-oxy (hydroxides). Adsorption equilibrium and kinetics were studied and modeled in terms of As oxidation state (III and V), pH and initial adsorbate concentration. Maximum adsorption capacities of 4.2 mg/g and 7.3 mg/g were obtained at pH 7 and 20 °C for arsenite and arsenate, respectively. When arsenite was used as adsorbate, experimental evidences pointed to the occurrence of redox reactions involving As(III) oxidation to As(V) and Fe(III) reduction to Fe(II), with As(V) uptake by the adsorbent. The proposed adsorption mechanism was then based on the assumption that arsenate was the adsorbed arsenic species. The most relevant drawback found in the present work was the considerable leaching of iron to the solution. Arsenite removal from a mining-influenced water by adsorption plus precipitation was studied and compared to a traditional process of coagulation/flocculation. Both kinds of treatment provided practically 100% of arsenite removal from the contaminated water, leading at best in 12.9 µg/L As after the adsorption and precipitation assays and 14.2 µg/L after the coagulation/flocculation process.


Assuntos
Arsênio , Ferro , Adsorção , Concentração de Íons de Hidrogênio , Alga Marinha , Água , Poluentes Químicos da Água , Purificação da Água
15.
Artigo em Inglês | MEDLINE | ID: mdl-27222283

RESUMO

The successful use of anaerobic reactors for bioremediation of acid mine drainage has been shown in systems with neutral pH. However, the choice of an efficient and suitable process for such wastewater must consider the capability of operating at acidic pH and in the presence of metals. This work studies the performance of an anaerobic batch reactor, under conditions of varying initial pH for its efficiencies in sulfate removal and metal precipitation from synthetic acid mine drainage. The chemical oxygen demand/sulfate (COD/SO4(2-)) ratio used was 1.00, with ethanol chosen as the only energy and carbon source. The initial pH of the synthetic drainage was progressively set from 7.0 to 4.0 to make it as close as possible to that of real acid mine drainage. Metals were also added starting with iron, zinc, and finally copper. The effectiveness of sulfate and COD removal from the synthetic acid mine drainage increased as the initial pH was reduced. The sulfate removal increased from 38.5 ± 3.7% to 52.2 ± 3%, while the removal of organic matter started at 91.7 ± 2.4% and ended at 99 ± 1%. These results indicate that the sulfate reducing bacteria (SRB) community adapted to lower pH values. The metal removal observed was 88 ± 7% for iron, 98.0 ± 0.5% for zinc and 99 ± 1% for copper. At this stage, an increase in the sulfate removal was observed, which reaches up to 82.2 ± 5.8%. The kinetic parameters for sulfate removal were 0.22 ± 0.04 h(-1) with Fe, 0.26 ± 0.04 h(-1) with Fe and Zn and 0.44 ± 0.04 h(-1) with Fe, Zn, and Cu.


Assuntos
Ácidos/química , Biodegradação Ambiental , Reatores Biológicos , Metais/química , Sulfatos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Concentração de Íons de Hidrogênio , Mineração
16.
Molecules ; 20(6): 10689-704, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26065834

RESUMO

Herpes simplex virus infections have been described in the medical literature for centuries, yet the the drugs available nowadays for therapy are largely ineffective and low oral bioavailability plays an important role on the inefficacy of the treatments. Additionally, the details of the inhibition of Herpes Virus type 1 are still not fully understood. Studies have shown that several viruses encode one or more proteases required for the production new infectious virions. This study presents an analysis of the interactions between HSV-1 protease and benzoxazinone derivatives through a combination of structure-activity relationships, comparative modeling and molecular docking studies. The structure activity relationship results showed an important contribution of hydrophobic and polarizable groups and limitations for bulky groups in specific positions. Two Herpes Virus type 1 protease models were constructed and compared to achieve the best model which was obtained by MODELLER. Molecular docking results pointed to an important interaction between the most potent benzoxazinone derivative and Ser129, consistent with previous mechanistic data. Moreover, we also observed hydrophobic interactions that may play an important role in the stabilization of inhibitors in the active site. Finally, we performed druglikeness and drugscore studies of the most potent derivatives and the drugs currently used against Herpes virus.


Assuntos
Antivirais/química , Antivirais/farmacologia , Benzoxazinas/química , Benzoxazinas/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/enzimologia , Modelos Moleculares , Peptídeo Hidrolases/química , Sítios de Ligação , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Conformação Molecular , Simulação de Acoplamento Molecular , Peso Molecular , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Ligação Proteica , Relação Estrutura-Atividade
17.
Molecules ; 20(5): 8072-93, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25951004

RESUMO

Tuberculosis (TB) remains a serious public health problem aggravated by the emergence of M. tuberculosis (Mtb) strains resistant to multiple drugs (MDR). Delay in TB treatment, common in the MDR-TB cases, can lead to deleterious life-threatening inflammation in susceptible hyper-reactive individuals, encouraging the discovery of new anti-Mtb drugs and the use of adjunctive therapy based on anti-inflammatory interventions. In this study, a series of forty synthetic chalcones was evaluated in vitro for their anti-inflammatory and antimycobacterial properties and in silico for pharmacokinetic parameters. Seven compounds strongly inhibited NO and PGE2 production by LPS-stimulated macrophages through the specific inhibition of iNOS and COX-2 expression, respectively, with compounds 4 and 5 standing out in this respect. Four of the seven most active compounds were able to inhibit production of TNF-α and IL-1ß. Chalcones that were not toxic to cultured macrophages were tested for antimycobacterial activity. Eight compounds were able to inhibit growth of the M. bovis BCG and Mtb H37Rv strains in bacterial cultures and in infected macrophages. Four of them, including compounds 4 and 5, were active against a hypervirulent clinical Mtb isolate as well. In silico analysis of ADMET properties showed that the evaluated chalcones displayed satisfactory pharmacokinetic parameters. In conclusion, the obtained data demonstrate that at least two of the studied chalcones, compounds 4 and 5, are promising antimycobacterial and anti-inflammatory agents, especially focusing on an anti-tuberculosis dual treatment approach.


Assuntos
Anti-Inflamatórios/farmacologia , Antituberculosos/farmacologia , Chalconas/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Animais , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/metabolismo , Óxidos de Nitrogênio/metabolismo , Tuberculose/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Molecules ; 19(5): 6651-70, 2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24858098

RESUMO

As part of a continuing search for new potential anticancer candidates, we describe the synthesis, cytotoxicity and mechanistic evaluation of a series of 4-oxoquinoline-3-carboxamide derivatives as novel anticancer agents. The inhibitory activity of compounds 10-18 was determined against three cancer cell lines using the MTT colorimetric assay. The screening revealed that derivatives 16b and 17b exhibited significant cytotoxic activity against the gastric cancer cell line but was not active against a normal cell line, in contrast to doxorubicin, a standard chemotherapeutic drug in clinical use. Interestingly, no hemolytical activity was observed when the toxicity of 16b and 17b was tested against blood cells. The in silico and in vitro mechanistic evaluation indicated the potential of 16b as a lead for the development of novel anticancer agents against gastric cancer cells.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Animais , Antineoplásicos/síntese química , Linhagem Celular Tumoral/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Técnicas de Química Sintética , Simulação por Computador , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Eritrócitos/efeitos dos fármacos , Hemolíticos/farmacologia , Humanos , Concentração Inibidora 50 , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Quinolonas/química , Neoplasias Gástricas/tratamento farmacológico
19.
Acta Med Port ; 37(4): 267-273, 2024 Apr 01.
Artigo em Português | MEDLINE | ID: mdl-38452740

RESUMO

INTRODUCTION: The aim of the study was to describe trauma injuries associated with rope bullfights in the Azores, Portugal, regarding the cause of the incident, trauma mechanism, most affected anatomical areas, and injury severity. METHODS: Two-year cross-sectional study in the local hospital with prospective data collection. Patients who were consecutively admitted to the local hospital's emergency department with trauma injuries from the bull's direct impact or from falls either during the bull's escape or when handling the rope, were included. Data on general demographics, lesion characteristics, treatments, need for hospitalization and mortality were collected. RESULTS: Fifty-six incidents and 80 trauma injuries were identified. The main cause of trauma was the bull's direct impact (37; 66.07%) and the mechanism of injury was blunt trauma in all patients (100%; 56). Head and neck injuries (27; 33.75%) were the most common. The median Injury Severity Score at the emergency department admission was 4. Major trauma was noted in five patients (8.92%). Ten patients (17.85%) needed hospitalization with a median hospital stay of seven days. Three of the 10 hospitalized patients (30%) were previously admitted to the intensive care unit. Surgery was performed in six patients (10.71%). CONCLUSION: The main cause of trauma was the bull's direct impact, and the mechanism of injury was blunt trauma. The most affected anatomical areas were the head and neck. These findings are a wake-up call to the impact of these events regarding the economic costs they entail, the costs for the health of the local population, the safety measures currently implemented and the availability of the necessary means to treat these patients.


Introdução: O objetivo deste estudo foi caracterizar as lesões traumáticas tauromáquicas ocorridas nas touradas à corda nos Açores no que diz respeito à causa do incidente, mecanismo de trauma, área anatómica mais afetada e gravidade das lesões. Métodos: Estudo unicêntrico, transversal, com a colheita prospetiva de dados realizada durante dois anos. Foram incluídos os doentes que consecutivamente recorreram ao serviço de urgência do hospital local por lesões traumáticas ocorridas por trauma direto com o animal ou quedas aquando da fuga ou manuseio da corda. Foram colhidos dados demográficos gerais, características da lesão, tratamentos efetuados, necessidade de internamento hospitalar e mortalidade. Foi realizada uma análise estatística descritiva com recurso ao software estatístico SPSS. Resultados: Registaram-se 56 admissões hospitalares e 80 lesões traumáticas. A principal causa de traumatismo foi o trauma direto com o animal (37; 66,07%) e o mecanismo de lesão foi o trauma fechado (56; 100%). As áreas anatómicas mais afetadas foram a cabeça e pescoço (27; 33,75%). A mediana de Injury Severity Score foi de 4 à admissão hospitalar. Cinco doentes (8,92%) apresentaram trauma major. Dez doentes (17,85%) necessitaram de internamento hospitalar com uma mediana de dias de internamento de sete (IIQ 4,5 dias). Três (30%) dos doentes internados necessitaram de internamento em unidade de cuidados intensivos. Seis doentes (10,71%) foram submetidos a cirurgia. Conclusão: A principal causa de traumatismo foi o trauma direto com o animal e o mecanismo de lesão foi o trauma fechado. As áreas anatómicas mais afetadas foram a cabeça e pescoço. Estes dados constituem um alerta para o impacto destes eventos no que diz respeito aos custos económicos que acarretam, aos custos para a saúde da população local, às medidas de segurança atualmente implementadas e à disponibilidade dos meios necessários para tratar estes doentes.


Assuntos
Hospitalização , Ferimentos não Penetrantes , Humanos , Masculino , Animais , Bovinos , Estudos Transversais , Açores , Tempo de Internação , Estudos Retrospectivos
20.
Eur J Case Rep Intern Med ; 10(3): 003764, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969523

RESUMO

Biliary hamartomas or von Meyenburg complexes (VMCs) are hepatic tumour-like lesions related to congenital malformation of the ductal plate, and are part of the ciliopathy spectrum of disorders. The exact pathogenesis of VMCs is unclear and it remains controversial whether they have the potential for malignant transformation. Patients are often asymptomatic and VMCs are usually encountered as an incidental finding on imaging. We report a case of recurrent sepsis with an unidentified focus. It was later confirmed that biliary hamartomas were acting as a sanctuary for the persistent pathogenic agent. The authors hope to draw attention to the existence of this unusual focus of recurrent sepsis. LEARNING POINTS: Hepatobiliary sepsis is an unusual clinical presentation of biliary hamartomas.Clinicians should be aware of the infectious complications of these diffuse structural biliary ductal abnormalities.Early recognition of this atypical life-threatening clinical presentation is important for the prognosis.

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