Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 143
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Molecules ; 28(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37630263

RESUMO

Cancer is a multifactorial disease that continues to increase. Lignans are known to be important anticancer agents. However, due to the structural diversity of lignans, it is difficult to associate anticancer activity with a particular subclass. Therefore, the present study sought to evaluate the association of lignan subclasses with antitumor activity, considering the genetic profile of the variants of the selected targets. To do so, predictive models were built against the targets tyrosine-protein kinase ABL (ABL), epidermal growth factor receptor erbB1 (EGFR), histone deacetylase (HDAC), serine/threonine-protein kinase mTOR (mTOR) and poly [ADP-ribose] polymerase-1 (PARP1). Then, single nucleotide polymorphisms were mapped, target mutations were designed, and molecular docking was performed with the lignans with the best predicted biological activity. The results showed more anticancer activity in the dibenzocyclooctadiene, furofuran and aryltetralin subclasses. The lignans with the best predictive values of biological activity showed varying binding energy results in the presence of certain genetic variants.


Assuntos
Perfil Genético , Lignanas , Simulação de Acoplamento Molecular , Histona Desacetilases , Lignanas/farmacologia , Serina-Treonina Quinases TOR
2.
Environ Monit Assess ; 195(12): 1539, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38012428

RESUMO

The aim of this study was to evaluate the effect of possible endocrine disruptors in surface and wastewater using a cell proliferation assay in an estrogen-responsive cell line (MCF-7). This study was conducted in the Sinos River (Brazil). The residual water was collected from a Pilot Treatment Plant (using Typha domingensis) and surface waters of the Luis Rau stream, the Sinos River, and the Water Treatment Station (WTS). After exposures (24-120 h), a Sulforhodamine B assay was performed to determine the proliferation rate. The higher increase in proliferation rate was observed with the Luiz Rau stream and the sewage treated by macrophytes in a flotation filter. The results from WTS water remained with a proliferation rate similar to the negative control at all times, suggesting that the conventional treatment is partially effective for the withdrawal of endocrine-disrupting agents. The study demonstrated the efficiency of the MCF-7 line in assessing endocrine disruption caused by wastewater and surface water samples. Our results indicate that conventional water treatment can partially remove the polluting load of endocrine disruptors, minimizing their environmental and public health impacts. Besides, it demonstrates the need to expand sanitary services to improve the population's quality of life.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água , Humanos , Disruptores Endócrinos/toxicidade , Disruptores Endócrinos/análise , Águas Residuárias , Monitoramento Ambiental/métodos , Brasil , Células MCF-7 , Qualidade de Vida , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Eliminação de Resíduos Líquidos/métodos
3.
Entropy (Basel) ; 25(9)2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37761658

RESUMO

We present the truncated Lindley-G (TLG) model, a novel class of probability distributions with an additional shape parameter, by composing a unit distribution called the truncated Lindley distribution with a parent distribution function G(x). The proposed model's characteristics including critical points, moments, generating function, quantile function, mean deviations, and entropy are discussed. Also, we introduce a regression model based on the truncated Lindley-Weibull distribution considering two systematic components. The model parameters are estimated using the maximum likelihood method. In order to investigate the behavior of the estimators, some simulations are run for various parameter settings, censoring percentages, and sample sizes. Four real datasets are used to demonstrate the new model's potential.

4.
Drug Chem Toxicol ; 45(2): 822-833, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32552192

RESUMO

Meloxicam is the non-steroidal anti-inflammatory drug most used in small animals; however, studies on genotoxicity, oxidative stress, and histopathologic alterations in cardiac tissue are limited, especially at therapeutical doses used in these animals. This study evaluated the toxic effects caused by the treatment involving repeated low at higher doses of meloxicam in mice, by genotoxicity, oxidative stress, and histopathological parameters. Mice (CF1, male) received, by gavage, meloxicam at the therapeutic dose indicated for small animals (0.1 mg/kg) and at higher doses (0.5 and 1 mg/kg) for 28 days. Later, they were euthanized for blood and organ analysis. Oxidative stress was analyzed by the plasma ferric reduction capacity (FRAP) and catalase, and genotoxicity, by the comet assay and the micronucleus test. Heart, liver, lung, and kidney tissues were analyzed by the histology, and stomach and duodenum were analyzed with a magnifying glass. The relative weight of organs did not present significant alterations. However, congestion of duodenum vessels was observed at the three tested doses and caused hyperemia of stomach mucosa at 1 mg/kg. In the heart histology there was a reduction in the number of cardiomyocytes, accompanied by an increase in cell diameter (possible cell hypertrophy) dose-dependent. The highest tested dose of meloxicam also increased the DNA damage index, without alterations in the micronucleus test. Meloxicam did not affect the catalase activity but increased the FRAP (1 mg/kg). Meloxicam at the dose prescribed for small animals could potentially cause cardiac histopathologic alterations and genotoxic effects.


Assuntos
Dano ao DNA , Coração , Animais , Ensaio Cometa , Fígado , Masculino , Meloxicam/toxicidade , Camundongos , Testes para Micronúcleos
5.
Artigo em Inglês | MEDLINE | ID: mdl-35852736

RESUMO

Although greater parent-child attachment security is linked with children's lower levels of depressive symptoms, little research has evaluated potential explanatory mechanisms. We investigated whether dispositional gratitude and interpersonal forgiveness explain the relation between attachment security with parents and early adolescents' depressive symptoms. Early adolescents (N = 105; M age = 12.3 years; 51% girls) completed questionnaires assessing their attachment security to mother and father figures, depressive symptoms, and dispositional gratitude, and an interview assessing interpersonal forgiveness. Results revealed that greater attachment security to mothers and fathers was associated with fewer depressive symptoms and greater levels of dispositional gratitude and interpersonal forgiveness. Further, dispositional gratitude and interpersonal forgiveness were negatively associated with depressive symptoms. Dispositional gratitude emerged as a mediator between attachment security with each parent and depressive symptoms. Our findings suggest that greater parent-child security may promote early adolescents' appreciation of positive events, which in turn may relate to fewer depressive symptoms.

6.
Toxicol Mech Methods ; 32(9): 705-715, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35410575

RESUMO

Schizophrenia is a psychiatric disorder that affects 1% of the world population and is treated with antipsychotics, which may induce important biochemical and hematological alterations. Since it is necessary to verify the safety of new molecules with antipsychotic potential, the present study aimed to evaluate the oral toxicity of PT-31, a putative α2-adrenoreceptor agonist, after acute (2000 mg/kg) and repeated doses (28 days) gavage treatment, in three different doses: minimum effective dose in animal models (10 mg/kg), twice the dose (20 mg/kg), and four times the dose (40 mg/kg), as recommended by the OECD guidelines. Balb/C female adult mice were used, and biochemical, hematological, and histopathological analyses were performed. PT-31 10 and 20 mg/kg did not cause biochemical alterations related to hepatic and renal toxicity, and neither altered glycemic and lipid profiles. The preclinical dose of PT-31 also did not promote mice histopathological changes in the liver, kidney, and brain. In the hematimetric parameters, PT-31 only increased HGB at 20 mg/kg, and MCH and MCHC at 40 mg/kg. However, all the tested doses of PT-31 showed platelet increase, which must be better investigated. Therefore, further studies are needed to investigate the safety of PT-31 as a potential antipsychotic drug.


Assuntos
Antipsicóticos , Animais , Antipsicóticos/toxicidade , Feminino , Humanos , Rim , Lipídeos , Fígado , Camundongos , Testes de Toxicidade Aguda
7.
J Environ Sci Health B ; 57(2): 133-141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35112655

RESUMO

Studies assessing the toxicity of glyphosate and 2,4-dichlorophenoxyacetic acid mixture are scarce. The aim of this study was to evaluate the cytotoxicity and genotoxicity of the mixture of these herbicides using Allium cepa. Roots were exposed to glyphosate (1.56 and 11.66 mg mL-1), 2,4-D (0.28 and 17.5 mg mL-1) and mixture for 24 h, based on the average concentration applied in the field and the acute reference dose (ARfD) established in Brazil. Both isolated and associated herbicides induced a significative decrease in mitotic index (MI) (P < 0.0001) in all tested concentrations. Regarding the genotoxicity results, 2,4-D and the mixture showed, at concentrations applied in the field, a significative increase of chromosomal anomalies (CA) index compared to control (P < 0.0001) and glyphosate (P = 0.024 and P = 0.0002, respectively). All tested groups from the ARfD showed a significative difference compared to the control group (P < 0.0001), as well as glyphosate and 2,4-D isolated compared to the mixture (P = 0.0005 and P < 0.0001, respectively). The most observed CA were apoptotic bodies, giant cells, and nuclear erosions. We emphasize the need for further studies assessing the toxicity of these herbicides' mixture due to the distinct effects caused in different organisms.


Assuntos
Herbicidas , Cebolas , Ácido 2,4-Diclorofenoxiacético/toxicidade , Bioensaio , Aberrações Cromossômicas/induzido quimicamente , Dano ao DNA , Glicina/análogos & derivados , Herbicidas/toxicidade , Índice Mitótico , Raízes de Plantas , Glifosato
8.
An Acad Bras Cienc ; 93(1): e20191526, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787753

RESUMO

The Environmental enrichment technique, although scientifically recognized for raising the level of animal welfare, has led to the questioning of its influence on the results of experimental research. Thus, the goal is to promote reflection about the need for standardization of these procedures. For that, documents and experimental analysis were done, in order to quantify and characterize the types of environmental enrichment used and to evaluate the effect of that in the social behavior of Rattus norvegicus. Data from the document review confirmed the hypothesis that the researchers have used a variety of methods, not demonstrating a concern for standardization and prior assessment of its effects on the search results. Demand was corroborated in the experimental study in which, although there was available a simple object acting as refuge promotes behavioral improvements, the presence of the co-specific, as well as characteristics of the micro and macro environment can compromise the homogeneity of the sample. The data from this study endorse the need for validation procedures of environmental enrichment for specific proposals, to investigative data comparison, are possible and contribute to the refinement of the search to reduce the number of animals targeted for this purpose.


Assuntos
Experimentação Animal , Criação de Animais Domésticos , Bem-Estar do Animal , Animais , Animais de Laboratório , Comportamento Animal , Abrigo para Animais , Ratos , Comportamento Social
9.
An Acad Bras Cienc ; 93(3): e20190619, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34406282

RESUMO

This study was conducted to evaluate the period of chromium yeast supplementation on lipid profile of backfat and Longissimus lumborum muscle of barrows. It was evaluated carcass samples from forty barrows, genetically similar. Pigs diets were supplemented with 0.4 mg kg-1 of chromium yeast in four periods (0, 38, 62 and 94 days before slaughter). The experimental design was completely randomized with four treatments, ten replicates, and each experimental unit consisting of one animal. Lipid profiles of backfat and Longissimus lumborum muscle were analyzed by gas chromatography. The increase in the period of chromium yeast use had a quadratic effect (P<0.05) for stearic and oleic fatty acids, and total saturated, monounsaturated and unsaturated fatty acids in backfat. DH-γ-linolenic and arachidonic fatty acids reduced when the period of chromium yeast use increased. In the meat, there was a quadratic effect (P<0.05) only in the γ-linoleic fatty acid. The use of chromium yeast for different periods influences the lipid profile of the backfat and the Longissimus lumborum muscle, with less effect in the meat.


Assuntos
Ácidos Graxos , Saccharomyces cerevisiae , Ração Animal/análise , Animais , Cromo , Suplementos Nutricionais , Lipídeos , Carne/análise , Suínos
10.
Molecules ; 26(3)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540716

RESUMO

BACKGROUND: The growing demand for agricultural products has led to the misuse/overuse of insecticides; resulting in the use of higher concentrations and the need for ever more toxic products. Ecologically, bioinsecticides are considered better and safer than synthetic insecticides; they must be toxic to the target organism, yet with low or no toxicity to non-target organisms. Many plant extracts have seen their high insecticide potential confirmed under laboratory conditions, and in the search for plant compounds with bioinsecticidal activity, the Lamiaceae family has yielded satisfactory results. OBJECTIVE: The aim of our study was to develop computer-assisted predictions for compounds with known insecticidal activity against Aphis gossypii and Drosophila melanogaster. RESULTS AND CONCLUSION: Structure analysis revealed ent-kaurane, kaurene, and clerodane diterpenes as the most active, showing excellent results. We also found that the interactions formed by these compounds were more stable, or presented similar stability to the commercialized insecticides tested. Overall, we concluded that the compounds bistenuifolin L (1836) and bistenuifolin K (1931), were potentially active against A. gossypii enzymes; and salvisplendin C (1086) and salvixalapadiene (1195), are potentially active against D. melanogaster. We observed and highlight that the diterpenes bistenuifolin L (1836), bistenuifolin K (1931), salvisplendin C (1086), and salvixalapadiene (1195), present a high probability of activity and low toxicity against the species studied.


Assuntos
Afídeos , Simulação por Computador , Diterpenos/química , Drosophila melanogaster , Inseticidas/química , Lamiaceae/química , Sequência de Aminoácidos , Animais , Afídeos/metabolismo , Drosophila melanogaster/metabolismo , Humanos , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Aprendizado de Máquina , Modelos Moleculares , Conformação Proteica
11.
Molecules ; 25(10)2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408657

RESUMO

Leishmaniasis is endemic in at least 98 countries. Due to the high toxicity and resistance associated with the drugs, we chose lignans as an alternative, due to their favorable properties of absorption, distribution, metabolism, excretion, and toxicity (ADMET). To investigate their leishmanicidal potential, the biological activities of a set of 160 lignans were predicted using predictive models that were built using data for Leishmania major and L. (Viannia) braziliensis. A combined analysis, based on ligand and structure, and several other computational approaches were used. The results showed that the combined analysis was able to select 11 lignans with potential activity against L. major and 21 lignans against L. braziliensis, with multitargeting effects and low or no toxicity. Of these compounds, four were isolated from the species Justicia aequilabris (Nees) Lindau. All of the identified compounds were able to inhibit the growth of L. braziliensis promastigotes, with the most active compound, (159) epipinoresinol-4-O-ß-d-glucopyranoside, presenting an IC50 value of 5.39 µM and IC50 value of 36.51 µM for L. major. Our findings indicated the potential of computer-aided drug design and development and demonstrated that lignans represent promising prototype compounds for the development of multitarget drugs against leishmaniasis.


Assuntos
Antiprotozoários/química , Desenho de Fármacos , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania major/crescimento & desenvolvimento , Lignanas , Simulação de Acoplamento Molecular , Avaliação Pré-Clínica de Medicamentos , Lignanas/química , Lignanas/farmacologia
12.
Environ Monit Assess ; 192(12): 755, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33170361

RESUMO

The present study aimed to evaluate the acute and chronic toxicity of environmentally relevant concentrations of metals (Mn, Al, Fe, and Pb) in Daphnia magna and the generational transposition of reproductive and morphological damages. The effective concentration for 10% of the organisms from each metal was obtained by the acute toxicity test (96 hours); then, another five concentrations lower than this one were defined for the chronic experimentation (21 days), in which the number of neonates generated by each individual was checked daily. At the end of the exposition, the lengths and number of morphological damages were recorded in each adult daphnid. During this, the molt generated on the 14th and 21st days were collected and cultivated for posterior evaluation of the same parameters. Alterations in the reproductive performance were observed in the organisms exposed to manganese and aluminum (4.0 and 0.5 mg L-1, respectively). Organisms exposed to aluminum (0.05 mg L-1) and iron (0.27 mg L-1) showed a reduction in body length. It is also noteworthy that the molt of these adults and their respective offspring also presented reproductive alterations, especially the molt from the 14th day of lead exposure (0.02 mg L-1) and the 21st day of manganese exposure (4.0 mg L-1). Such effects allow us to conclude that environments polluted by metals can reduce the ability of the species to maintain themselves in the ecosystem. In addition, there is a need to increase the control and monitoring of metals, such as aluminum, which present risks even in low concentrations.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Animais , Daphnia , Ecossistema , Monitoramento Ambiental , Humanos , Recém-Nascido , Metais/toxicidade , Reprodução , Poluentes Químicos da Água/toxicidade
13.
BMC Infect Dis ; 18(1): 53, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29370774

RESUMO

BACKGROUND: Tuberculosis (TB) incidence is decreasing worldwide and eradication is becoming plausible. In low-incidence countries, intervention on migrant populations is considered one of the most important strategies for elimination. However, such measures are inappropriate in European areas where TB is largely endemic, such as Porto in Portugal. We aim to understand transmission chains in Porto through a genetic characterization of Mycobacterium tuberculosis strains and through a detailed epidemiological evaluation of cases. METHODS: We genotyped the M. tuberculosis strains using the MIRU-VNTR system. We performed an evolutionary reconstruction of the genotypes with median networks, used in this context for the first time. TB cases from a period of two years were evaluated combining genetic, epidemiological and georeferencing information. RESULTS: The data reveal a unique complex scenario in Porto where the autochthonous population acts as a genetic reservoir of M. tuberculosis diversity with discreet episodes of transmission, mostly undetected using classical epidemiology alone. CONCLUSIONS: Although control policies have been successful in decreasing incidence in Porto, the discerned complexity suggests that, for elimination to be a realistic goal, strategies need to be adjusted and coupled with a continuous genetic characterization of strains and detailed epidemiological evaluation, in order to successfully identify and interrupt transmission chains.


Assuntos
Mycobacterium tuberculosis/genética , Tuberculose/transmissão , Feminino , Genótipo , Humanos , Repetições Minissatélites , Epidemiologia Molecular/métodos , Mycobacterium tuberculosis/patogenicidade , Portugal , Fatores Socioeconômicos , Tuberculose/epidemiologia , Tuberculose/genética
14.
Planta ; 246(5): 899-914, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28702689

RESUMO

MAIN CONCLUSION: The set of variables analyzed as integrated by multivariate analysis of principal components consistently showed a memory effect induced by the drought pre-treatment in AN Cambará plants. The effects of drought can vary ddepending on many factors. Among these the occurrence of a previous water stress may leave a residual effect (memory), influencing the future performance of a plant in response to a new drought event. This study tested the hypothesis that plants experiencing recurrent drought would show more active mechanisms of water deficit tolerance, mainly plants of the genotype that is cultivated often experiencing water shortages periods. Additionally, all the plants subjected to water deficit were rehydrated by 24 h and the expression of transcription factors related to drought responses was re-evaluated. To this end, the water status of two rice genotypes, BRS Querência (flooded) and AN Cambará (dryland), was evaluated to identify molecular alterations likely underpinning drought-memory. In growth stage V5, some plants were exposed to water stress (10% VWC soil moisture-pre-treatment). Thereafter, the pots were rehydrated at the same level as the control pots and maintained under this condition until drought was reapplied (10% VWC) at the reproductive stage (R1-R2). Then, the plants were rehydrated and maintained at pot capacity for 24 h. Overall, the set of variables analyzed integrally by multivariate analysis of principal components consistently showed a memory effect induced by the drought pre-treatment in AN Cambará plants (the dryland genotype). This conclusion, based on data of the biochemical and molecular analyses, was supported by the greater capacity of maintenance of the water status by stomatal regulation of the pre-treated and rehydrated plants after the second drought stimulus.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/fisiologia , Estresse Fisiológico , Antioxidantes/metabolismo , Desidratação , Secas , Perfilação da Expressão Gênica , Genótipo , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estômatos de Plantas/genética , Estômatos de Plantas/fisiologia , Prolina/metabolismo , Solo , Água/fisiologia
15.
BMC Nephrol ; 18(1): 287, 2017 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-28877670

RESUMO

BACKGROUND: Indoleamine 2, 3-dioxygenase (IDO) is an immunomodulatory molecule that has been implicated in several biological processes. Although IDO has been linked with some renal diseases, its role in renal fibrosis is still unclear. Because IDO may be modulated by TGF-ß1, a potent fibrogenic molecule, we hypothesized that IDO could be involved in renal fibrosis, especially acting in the TGF-ß1-induced tubular epithelial-mesenchymal transition (EMT). We analyzed the IDO expression and activity in a model of renal fibrogenesis, and the effect of the IDO inhibitor 1-methyl-tryptophan (MT) on TGF-ß1-induced EMT using tubular cell culture. METHODS: Male Wistar rats where submited to 7 days of UUO. Non-obstructed kidneys (CL) and kidneys from SHAM rats were used as controls. Masson's Tricrome and macrophages counting were used to chatacterize the tissue fibrosis. The EMT was analysed though immunohistochemistry and qRT-PCR. Immunohistochemestry in tissue has used to show IDO expression. MDCK cells were incubated with TGF- ß1 to analyse IDO expression. Additionally, effects of TGF- ß1 and the inhibition of IDO over the EMT process was acessed by immunoessays and scrath wound essay. RESULTS: IDO was markedly expressed in cortical and medular tubules of the UUO kidneys. Similarly to the immunolocalizaton of TGF- ß1, accompanied by loss of e-cadherin expression and an increase of mesenchymal markers. Results in vitro with MDCK cells, showed that IDO was increased after stimulus with TGF-ß1, and treatment with MT potentiated its expression. MDCK stimulated with TGF-ß1 had higher migratory activity (scratch-wound assay), which was exacerbated by MT treatment. CONCLUSIONS: IDO is constitutively expressed in tubular cells and increases during renal fibrogenesis. Although IDO is induced by TGF-ß1 in tubular cells, its chemical inhibitor acts as a profibrotic agent.


Assuntos
Transição Epitelial-Mesenquimal/fisiologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/biossíntese , Nefropatias/metabolismo , Nefropatias/patologia , Fator de Crescimento Transformador beta1/biossíntese , Animais , Cães , Fibrose/metabolismo , Fibrose/patologia , Células Madin Darby de Rim Canino , Masculino , Ratos , Ratos Wistar , Triptofano/análogos & derivados , Triptofano/farmacologia
16.
Photochem Photobiol Sci ; 15(12): 1503-1513, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27830217

RESUMO

Candida albicans is a human pathogenic fungus mainly affecting immunocompromised patients. Resistance to the commonly used fungicides can lead to poor treatment of mucosal infections which, in turn, can result in life-threatening systemic candidiasis. In this scenario, antimicrobial photodynamic treatment (PDT) has emerged as an effective alternative to treat superficial and localized fungal infections. Microbial death in PDT is a consequence of the oxidation of many cellular biomolecules, including proteins. Here, we report a combination of two-dimensional electrophoresis and tandem mass spectrometry to study the protein damage resulting from treating C. albicans with PDT with new methylene blue N and red light. Two-dimensional gels of treated cells showed an increase in acidic spots in a fluence-dependent manner. Amino acid analysis revealed a decrease in the histidine content after PDT, which is one plausible explanation for the observed acidic shift. However, some protein spots remained unchanged. Protein identification by mass spectrometry revealed that both modified and unmodified proteins could be localized to the cytoplasm, ruling out subcellular location as the only explanation for damage selectivity. Therefore, we hypothesize that protein modification by PDT is a consequence of both photosensitizer binding affinity and the degree of exposure of the photooxidizable residues on the protein surface.


Assuntos
Candidíase/terapia , Azul de Metileno/análogos & derivados , Fotoquimioterapia , Proteoma/efeitos dos fármacos , Proteoma/efeitos da radiação , Candida albicans/efeitos dos fármacos , Candida albicans/efeitos da radiação , Humanos , Luz , Azul de Metileno/farmacologia , Fármacos Fotossensibilizantes/farmacologia
17.
Foodborne Pathog Dis ; 12(6): 479-85, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25974222

RESUMO

The frequent use of antimicrobials in commercial poultry production has raised concerns regarding the potential impact of antimicrobials on human health due to selection for resistant bacteria. Several studies have reported similarities between extraintestinal pathogenic Escherichia coli (ExPEC) strains isolated from birds and humans, indicating that these contaminant bacteria in poultry may be linked to human disease. The aim of our study was to analyze the frequency of antimicrobial resistance and virulence factors among E. coli strains isolated from commercial chicken carcasses in Paraná, Brazil, in 2007 and 2013. A total of 84 E. coli strains were isolated from chicken carcasses in 2007, and 121 E. coli strains were isolated in 2013. Polymerase chain reaction was used to detect virulence genes (hlyF, iss, ompT, iron, and iutA) and to determine phylogenetic classification. Antimicrobial susceptibility testing was performed using 15 antimicrobials. The strains were also confirmed as extended-spectrum ß-lactamase (ESBL)-producing E. coli with phenotypic and genotypic tests. The results indicated that our strains harbored virulence genes characteristic of ExPEC, with the iutA gene being the most prevalent. The phylogenetic groups D and B1 were the most prevalent among the strains isolated in 2007 and 2013, respectively. There was an increase in the frequency of resistance to a majority of antimicrobials tested. An important finding in this study was the large number of ESBL-producing E. coli strains isolated from chicken carcasses in 2013, primarily for the group 2 cefotaximase (CTX-M) enzyme. ESBL production confers broad-spectrum resistance and is a health risk because ESBL genes are transferable from food-producing animals to humans via poultry meat. These findings suggest that our strains harbored virulence and resistance genes, which are often associated with plasmids that can facilitate their transmission between bacteria derived from different hosts, suggesting zoonotic risks.


Assuntos
Antibacterianos/farmacologia , Galinhas/microbiologia , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Carne/microbiologia , Fatores de Virulência/metabolismo , Animais , Anti-Infecciosos/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Brasil , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Inspeção de Alimentos , Microbiologia de Alimentos/tendências , Isoenzimas/genética , Isoenzimas/metabolismo , Carne/economia , Tipagem Molecular , Filogenia , Fatores de Virulência/genética , beta-Lactamases/genética , beta-Lactamases/metabolismo
18.
Appl Environ Microbiol ; 80(5): 1623-32, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24362436

RESUMO

The increasing tolerance to currently used fungicides in both clinical and agricultural areas is of great concern. The nonconventional light-based approach of antimicrobial photodynamic treatment (APDT) is a promising alternative to conventional fungicides. We evaluated the effects of APDT with four phenothiazinium derivatives (methylene blue [MB], new methylene blue N [NMBN], toluidine blue O [TBO], and the novel pentacyclic phenothiazinium photosensitizer [PS] S137) on conidia of three fungal species (Colletotrichum acutatum, Colletotrichum gloeosporioides, and Aspergillus nidulans). The efficacy of APDT with each PS was determined, initially, based on photosensitizer MICs. Additionally, the effects of APDT with two selected PSs (NMBN and S137) on survival of conidia were evaluated. The subcellular localization of the PS in C. acutatum conidia was determined. The effects of photodynamic treatments on leaves of the plant host Citrus sinensis were also investigated. APDT with S137 showed the lowest MIC. MICs for S137 were 5 µM for the three fungal species when a fluence of 25 J cm(-2) was used. APDT with NMBN (50 µM) and S137 (10 µM) resulted in a reduction in the survival of the conidia of all species of approximately 5 logs with fluences of ≥15 J cm(-2). Washing of the conidia before light exposure did not prevent photodynamic inactivation. Both NMBN and S137 accumulated in cytoplasmic structures, such as lipid bodies, of C. acutatum conidia. No damage to orange tree leaves was observed after APDT.


Assuntos
Antifúngicos/farmacologia , Colletotrichum/efeitos dos fármacos , Colletotrichum/fisiologia , Viabilidade Microbiana/efeitos dos fármacos , Fenotiazinas/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Aspergillus nidulans/efeitos dos fármacos , Aspergillus nidulans/fisiologia , Citrus sinensis/microbiologia , Fungos , Testes de Sensibilidade Microbiana , Esporos Fúngicos/efeitos dos fármacos
19.
J Anxiety Disord ; 101: 102795, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38039916

RESUMO

Although theory suggests that empathy may signal a risk for anxiety (Tone & Tully, 2014), the relation between these constructs remains unclear due to the lack of a quantitative synthesis of empirical findings. We addressed this question by conducting three meta-analyses assessing anxiety and general, cognitive, and affective empathy (k's = 70-102 samples; N's = 19,410-25,102 participants). Results suggest that anxiety has a small and significant association with general empathy (r = .08). The relation of clinical anxiety with cognitive empathy was significant but very weak (r = -.03), and small for affective empathy (r = .16). Geographic region and the type of cognitive (e.g., perspective taking, fantasy) and affective empathy (e.g., affective resonance, empathic concern) emerged as moderators. Results suggest that anxiety has a weaker association with general empathy but a stronger association with affective empathy in participants from predominantly collectivistic geographic regions. Further, greater anxiety was weakly associated with less perspective-taking and greater fantasy, and anxiety had a more modest association with empathic concern than other types of affective empathy. Targeting affective empathy (e.g., promoting coping strategies when faced with others' distress) in interventions for anxiety may be beneficial.


Assuntos
Ansiedade , Empatia , Humanos , Ansiedade/psicologia , Transtornos de Ansiedade
20.
Heliyon ; 10(8): e29063, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644857

RESUMO

Lippia alba (Mill.) N.E. Brown (Verbenaceae), popularly known as "erva cidreira", is one of the most used plants in Brazilian folk medicine. The species has several chemotypes and its volatile constituents have already been characterized, and present different chemical markers with known pharmacological properties, such as analgesic, sedative and antifungal properties. The objective of this study was to evaluate the anticholinesterase activity (AChE) of the essential oil of three chemotypes of Lippia alba and, by using molecular anchoring, determine the best receptor-ligand interaction energies of the main constituents present in the samples of oil. The essential oils were obtained via hydrodistillation (LA1 and LA2) and steam drag (LA3), and their volatile constituents determined using GC-MS. For the determination of anticholinesterase activity, direct bioautography and colorimetry assays based on Ellman's method were used. Molecular docking was performed using a multiple solution genetic algorithm and Merck molecular force field 94 (MMFF94) as the scoring function. In the main constituents of the oil samples, three chemotypes were identified for L. alba: LA1 is rich in citral, LA2 is rich in carvone and LA3 is rich in linalool. All L. alba chemotypes showed AChE enzyme inhibition with an IC50 of 3.57 µg/mL (LA1), 0.1 µg/mL (LA2) and 4.34 µg/mL (LA3). The molecular docking study complemented the results of the experiment and demonstrated significant interactions between the main constituents of the oils and the amino acid residues of the AChE enzyme. Irrespective of the chemotype, Lippia alba presents biotechnological potential for the discovery of anticholinesterase substances, with the chemotype LA2 (rich in carvone) being the most active.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA