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1.
JHEP Rep ; 6(1): 100918, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38192540

RESUMO

Background & Aims: Current therapies for the treatment of alcohol-related liver disease (ALD) have proven largely ineffective. Patients relapse and the disease progresses even after liver transplantation. Altered epigenetic mechanisms are characteristic of alcohol metabolism given excessive acetate and NAD depletion and play an important role in liver injury. In this regard, novel therapeutic approaches based on epigenetic modulators are increasingly proposed. MicroRNAs, epigenetic modulators acting at the post-transcriptional level, appear to be promising new targets for the treatment of ALD. Methods: MiR-873-5p levels were measured in 23 liver tissue from Patients with ALD, and GNMT levels during ALD were confirmed using expression databases (transcriptome n = 62, proteome n = 68). High-resolution proteomics and metabolomics in mice following the Gao-binge model were used to investigate miR-873-5p expression in ALD. Hepatocytes exposed to 50 mM alcohol for 12 h were used to study toxicity. The effect of anti-miR-873-5p in the treatment outcomes of ALD was investigated. Results: The analysis of human and preclinical ALD samples revealed increased expression of miR-873-5p in the liver. Interestingly, there was an inverse correlation with NNMT, suggesting a novel mechanism for NAD depletion and aberrant acetylation during ALD progression. High-resolution proteomics and metabolomics identified miR-873-5p as a key regulator of NAD metabolism and SIRT1 deacetylase activity. Anti-miR-873-5p reduced NNMT activity, fuelled the NAD salvage pathway, restored the acetylome, and modulated the levels of NF-κB and FXR, two known SIRT1 substrates, thereby protecting the liver from apoptotic and inflammatory processes, and improving bile acid homeostasis. Conclusions: These data indicate that targeting miR-873-5p, a repressor of GNMT previously associated with NAFLD and acetaminophen-induced liver failure. is a novel and attractive approach to treating alcohol-induced hepatoxicity. Impact and implications: The role of miR-873-5p has not been explicitly examined in the progression of ALD, a pathology with no therapeutic options. In this study, inhibiting miR-873-5p exerted hepatoprotective effects against ALD through rescued SIRT1 activity and consequently restored bile acid homeostasis and attenuated the inflammatory response. Targeting hepatic miR-873-5p may represent a novel therapeutic approach for the treatment of ALD.

2.
Life Sci ; 327: 121840, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37290667

RESUMO

BACKGROUND: Malathion (MAL) is an organophosphate insecticide that inhibits cholinesterases, used to control pests in agriculture and to combat mosquitoes that transmit various arboviruses. As acetylcholine is one of the major neurotransmitters of the enteric nervous system (ENS), humans exposed to MAL by ingestion of contaminated food and water can develop symptoms due disfunction of the gastrointestinal tract. Although the deleterious effects after exposure to high doses are recognized, little is known about the long-term and low-dose effects of this pesticide on the structure and motility of the colon. AIMS: to evaluate the effects of prolonged oral exposure to low levels of MAL on the wall structure and colonic motility parameters of young rats. MAIN METHODS: The animals were divided into three groups: control, and groups that received 10 or 50 mg/kg of MAL via gavage for 40 days. The colon was collected for histological analysis and analysis of the ENS through the evaluation of total neurons and subpopulations of the myenteric and submucosal plexuses. Cholinesterase activity and functional analyzes of the colon were evaluated. KEY FINDINGS: MAL treatments (10 and 50 mg/Kg) reduced the butyrylcholinesterase activity, and caused enlargement of faecal pellets, atrophy of muscle layers and several changes in neurons of both myenteric and submucosal plexi. Considering colonic contraction, MAL (50 mg/Kg) increased the number of retrograde colonic migratory motor complexes. SIGNIFICANCE: The long-term exposure to low doses of MAL affects colonic morphophysiology, which highlights the need to intensify control and care in the use of this pesticide.


Assuntos
Sistema Nervoso Entérico , Praguicidas , Humanos , Ratos , Animais , Malation/toxicidade , Butirilcolinesterase , Colo
3.
J Anal Toxicol ; 47(3): 227-235, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36124733

RESUMO

The use of new psychoactive substances has been increasing and constitutes a social and public health problem, and hence, toxicological analysis has become of utmost importance for the detection of such substances. In this article, we present the development and full validation of a simple, user and environmentally friendly, cheap and suitable method for the determination of ketamine and its main metabolite norketamine in hair samples. The procedure included using a miniaturized procedure-microextraction by packed sorbent with mixed-mode sorbent-for sample clean-up. Organic solvents use was minimal, and it was possible to obtain a linear method (0.05-10 ng/mg for both analytes). The extraction efficiency ranged from 32 to 61%, which did not impair sensitivity. The method proved to be selective, precise, accurate and suitable for routine analysis for the determination of said compounds in 50-mg hair samples.


Assuntos
Ketamina , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Reprodutibilidade dos Testes , Cabelo/química , Microextração em Fase Sólida/métodos
4.
Foods ; 10(11)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34828841

RESUMO

The aim was to characterise the extent of processing and nutritional composition of the street foods offered in Maputo, Mozambique. A cross-sectional study was conducted in October-November 2014 in the urban district of KaMpfumu. Twenty public transport stops were randomly selected, around which 500 meters buffers were drawn. All streets within these buffers were canvassed to identify all street food vending sites. Street food offer was assessed through interviews. Nutritional composition was estimated using standardised recipes (for homemade foods), food labels (for industrial products) and food composition tables (for in natura foods). The processing extent was classified using the "NOVA" food classification. A total of 810 vending sites were assessed. Unprocessed/minimally processed foods were available at 70.5% of vending sites (mainly fruit, water, and tea) and ultra-processed foods at 59.0% (mostly cakes, cookies, confectionery, and soft drinks). Energy content per 100 g of unprocessed or minimally processed foods was significantly lower than in all other food groups. In all food groups, contribution to total energy value was highest for carbohydrates (range: 33.1-51.2%), followed by fats (range: 29.3-36.0%) and protein (range: 6.8-18.6%). Public health policies targeting the improvement of this urban food environment should consider not only the nutritional composition but also the processing extent of the foods and beverages available.

5.
Physiol Rep ; 9(3): e14731, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33587339

RESUMO

We measured plasma-derived extracellular vesicle (EV) proteins and their microRNA (miRNA) cargos in normoglycemic (NG), glucose intolerant (GI), and newly diagnosed diabetes mellitus (DM) in middle-aged male participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brazil). Mass spectrometry revealed decreased IGHG-1 and increased ITIH2 protein levels in the GI group compared with that in the NG group and higher serotransferrin in EVs in the DM group than in those in the NG and GI groups. The GI group also showed increased serum ferritin levels, as evaluated by biochemical analysis, compared with those in both groups. Seventeen miRNAs were differentially expressed (DEMiRs) in the plasma EVs of the three groups. DM patients showed upregulation of miR-141-3p and downregulation of miR-324-5p and -376c-3p compared with the NG and GI groups. The DM and GI groups showed increased miR-26b-5p expression compared with that in the NG group. The DM group showed decreased miR-374b-5p levels compared with those in the GI group and higher concentrations than those in the NG group. Thus, three EV proteins and five DEMiR cargos have potential prognostic importance for diabetic complications mainly associated with the immune function and iron status of GI and DM patients.


Assuntos
Proteínas Sanguíneas/análise , Diabetes Mellitus/sangue , Diabetes Mellitus/genética , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , MicroRNAs/genética , Proteoma , Transcriptoma , Adulto , Fatores Etários , Idoso , Glicemia/análise , Brasil/epidemiologia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Perfilação da Expressão Gênica , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Proteômica , Medição de Risco , Fatores de Risco , Fatores Sexuais
6.
J Chemother ; 33(2): 106-115, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33480330

RESUMO

PURPOSE: This study aimed to evaluate markers of cardiac damage (total CK, CKMB and CRP), inflammatory markers (free iron, homocysteine and TNF-α) as well as lipidogram in breast cancer patients undergoing acute cycles of doxorubicin (DOX), paclitaxel (PTX) or trastuzumab (TZ) and to verify if there is an association between these markers and the toxicity of the chemotherapeutic treatment. Methods: Included in the study were 120 breast cancer patients and 50 healthy controls. All analyzes were performed on automated systems. For the statistical analysis, each group was compared with the controls according to their normality by Student's t-test and Mann-Whitney test. Results: Our results showed that DOX treatment led to increased hsCRP (4.80 ± 1.23 mg/dL, p = 0.0005), triglycerides (187.6 ± 25.06, p = 0.0231), TNF-α (42.31 ± 17.96 pg/mL, p = 0.01) and Fe levels (138.8 ± 18.6 µg/dL, p = 0.0193). In the meantime, PTX induced changes in CK-MB (8.78 ± 4.2 U/L, p = 0.0361), hsCRP (7.12 ± 1.87 mg/dL, p = 0.0006), cholesterol (201.7 ± 19.54, p = 0.05), triglycerides (201.7 ± 19.54, p = 0.0277), TNF-α (38.27 ± 9.12 pg/mL, p = 0.023), homocysteine (10.95 ± 0, 86 µmol/L, p = 0.005), and free iron (113 ± 18 6 µg/dL, p = 0.045) while TZ augmented CK-MB (6.9 ± 1.97 U/L, p < 0.00), hsPCR (3.12 ± 0.68 mg/dL, p = 0.095), cholesterol (218.3 ± 16.79, p = 0.0317), triglycerides (218.3 ± 16.79, p = 0.0127), TNF-α (89.6 ± 12.11, p = 0.032), homocysteine (9.95 ± 1.15 µmol/L, p = 0.0396), free iron (120.5 ± 4.64 µg/dl, p = 0.0058) as well. Conclusions: Our data demonstrated the existence of a proinflammatory net triggered by breast cancer chemotherapy that could increase cardiomyocytes permeability and allow the leakage of circulating proteins as CK-MB and induce the production of hsCRP.


Assuntos
Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cardiopatias/induzido quimicamente , Mediadores da Inflamação/metabolismo , Adulto , Idoso , Antineoplásicos/uso terapêutico , Biomarcadores , Doxorrubicina/efeitos adversos , Doxorrubicina/farmacologia , Feminino , Humanos , Pessoa de Meia-Idade , Paclitaxel/efeitos adversos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Trastuzumab/efeitos adversos , Trastuzumab/farmacologia
7.
Langmuir ; 35(47): 15232-15241, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31702926

RESUMO

Matrix vesicles (MVs) are a special class of extracellular vesicles that drive bone and dentin mineralization by providing the essential enzymes and ions for the nucleation and propagation of mineral crystals. Tissue-nonspecific alkaline phosphatase (TNAP) is an integral protein of MV membrane and participates in biomineralization by hydrolyzing extracellular pyrophosphate (PPi), a strong mineralization inhibitor, and forming inorganic phosphate (Pi), necessary for the growth of mineral crystals inside MVs and their propagation once released in the extracellular matrix. MV membrane is enriched in cholesterol (CHOL), which influences the incorporation and activity of integral proteins in biologic membranes; however, how CHOL controls the incorporation and activity of TNAP in MV membrane has not yet been elucidated. In the present study, Langmuir monolayers were used as a MV membrane biomimetic model to assess how CHOL affects TNAP incorporation and activity. Surface pressure-area (π-A) isotherms of binary dipalmitoilphosphatidylcholine (DPPC)/CHOL monolayers showed that TNAP incorporation increases with CHOL concentration. Infrared spectroscopy showed that CHOL influences the conformation and orientation of the enzyme. Optical-fluorescence micrographs of the monolayers revealed the tendency of TNAP to incorporate into CHOL-rich microdomains. These data suggest that TNAP penetrates more efficiently and occupies a higher surface area into monolayers with a lower CHOL concentration due to the higher membrane fluidity. However, the quantity of enzyme transferred to solid supports as well as the enzymatic activity were higher using monolayers with a higher CHOL concentration due to increased rigidity that changes the enzyme orientation at the air-solid interface. These data provide new insights regarding the interfacial behavior of TNAP and CHOL in MVs and shed light on the biochemical and biophysical processes occurring in the MV membrane during biomineralization at the molecular level.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/metabolismo , Fosfatase Alcalina/metabolismo , Colesterol/metabolismo , Membranas Artificiais , 1,2-Dipalmitoilfosfatidilcolina/química , Fosfatase Alcalina/química , Catálise , Colesterol/química , Ligação Proteica
8.
Phys Chem Chem Phys ; 21(8): 4155-4161, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30520481

RESUMO

The complex conformational space of the non-proteinogenic cyclic amino acid pipecolic acid has been explored in the gas phase for the first time. Solid pipecolic acid samples were vaporized by laser ablation and expanded in a supersonic jet where the rotational spectral signatures owing to nine different conformers were observed by Fourier transform microwave spectroscopy. All species were identified by comparison of the experimental rotational and nuclear quadrupole coupling constants with those predicted theoretically. Observation of type-III conformers, leading to a difference when compared against the conformational behavior of the analog amino acid proline, has been interpreted by an increment in steric hindrance when increasing the number of carbons present in the ring.


Assuntos
Ácidos Pipecólicos/química , Análise de Fourier , Gases/química , Ligação de Hidrogênio , Lasers , Micro-Ondas , Modelos Moleculares , Conformação Molecular , Prolina/química , Termodinâmica
9.
Nutr Health ; 25(1): 37-46, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30522397

RESUMO

BACKGROUND:: A nutrition transition is occurring in the urban areas of developing countries, where street food makes an important contribution to daily food intake. AIM:: We aimed to characterise street food offer in Maputo, Mozambique, and to evaluate the nutritional composition of the most common homemade foods. METHODS:: A cross-sectional study was conducted in 2014. Streets in the surroundings (500 m buffer) of randomly selected public transport stops in KaMpfumu district, Maputo, were canvassed to identify all street food vending sites ( n = 968). Information regarding vending site characteristics and the food offered was gathered through interview and observation. Samples ( n = 80) of the most common homemade foods were collected for laboratorial analysis. RESULTS:: Most street food vending sites identified were stationary (77.4%) and sold exclusively industrial food (51.9%). Frequency of fruit, beverages and food other than fruit was 24.5%, 32.5% and 73.9%, respectively. Fried cakes were the most energy-dense (430 kcal/100 g), and richest in fats (21.0g/100 g) and carbohydrates (53.4 g/100 g). The richest sources of protein were the stewed meat/fish/liver dishes (10.7-11.6 g/100 g). Fried cakes showed the lowest sodium and potassium content (90 mg/100 g and 81 mg/100 g, respectively) whereas hamburgers exhibited the highest content of those micronutrients (455 mg/100 g and 183 mg/100 g, respectively). Stewed liver dishes presented the highest sodium/potassium ratio (11.95). Fried snacks presented the highest trans-fatty acid content (0.20 g/100 g). CONCLUSIONS:: Street food in Maputo is abundant and scattered throughout the urban district, exhibiting high variability in the nutritional composition of homemade foods. Public health policies should be targeted to improve the street food offer, promoting nutrient-dense foods and the reduction of added salt.


Assuntos
Comércio , Dieta , Abastecimento de Alimentos , Nutrientes/análise , Valor Nutritivo , População Urbana , Bebidas , Cidades , Estudos Transversais , Países em Desenvolvimento , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Humanos , Carne , Moçambique , Nutrientes/administração & dosagem , Estado Nutricional , Potássio na Dieta/administração & dosagem , Potássio na Dieta/análise , Alimentos Marinhos , Lanches , Sódio na Dieta/administração & dosagem , Sódio na Dieta/análise , Ácidos Graxos trans/administração & dosagem , Ácidos Graxos trans/análise
11.
Lupus ; 27(3): 380-388, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29400123

RESUMO

Background This study was performed to assess adhesion molecules in systemic lupus erythematosus (SLE). Methods This case-control study examined 126 SLE patients and 48 healthy individuals. Blood levels of six adhesion molecules, cortisol, nuclear autoantibody (ANA) and anti-double stranded DNA (anti-dsDNA) titers were measured, while disease activity was assessed using the SLE Disease Activity Index (SLEDAI) score. Results Platelet endothelial cell adhesion molecule 1 (PECAM-1), vascular cell adhesion molecule 1 (VCAM-1), E-selectin, P-selectin, and plasminogen activator inhibitor type-1 (PAI-1) were significantly higher in SLE patients than in controls. Binary logistic regression analysis showed that PECAM-1 and PAI-1 predicted SLE with a sensitivity of 86.5% and a specificity of 81.3%. ANA titers were significantly and positively associated with PECAM-1, VCAM-1, E-selectin, and PAI-1, whereas there were no associations between anti-dsDNA titers and adhesion molecules. Cortisol was negatively associated with PCAM-1 and ICAM-1. There were significant associations between metabolic syndrome (MetS) and E-selectin and PAI-1. 14.8% of the variance in the SLEDAI score was explained by the regression on PECAM-1 and MetS. Conclusions Our data show that adhesion molecules, especially PECAM-1, are significantly associated with SLE and disease activity, suggesting that they play a role in SLE pathophysiology. While MetS, ANA titers and cortisol levels modulate adhesion molecule levels, these associations do not explain the increased levels of adhesion molecules in SLE. Increased levels of adhesion molecules are new drug targets in SLE.


Assuntos
Anticorpos Antinucleares/sangue , Autoimunidade , Moléculas de Adesão Celular/sangue , Hidrocortisona/sangue , Lúpus Eritematoso Sistêmico/sangue , Síndrome Metabólica/complicações , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Brasil , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Índice de Gravidade de Doença
12.
Cancer Chemother Pharmacol ; 80(3): 469-478, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28689298

RESUMO

PURPOSE: Although paclitaxel-based chemotherapy is widely used for treating breast cancer, paclitaxel therapy has been associated with several adverse effects. Such adverse effects have primarily been associated with long-term regimens, but some acute effects are being increasingly reported in the literature. In this context, the present study analyzed the systemic proteomic profiles of women diagnosed with breast cancer at the first cycle of short paclitaxel infusion (n = 30). Proteomic profiles thus obtained were compared with those of breast cancer patients without chemotherapy (n = 50), as well as with those of healthy controls (n = 40). METHODS: Plasma samples were evaluated by label-free LC-MS to obtain systemic proteomic profiles. Putative dysregulated pathways were identified and validated by in silico analysis of proteomic profiles. RESULTS: Our results identified 188 proteins that were differentially expressed in patients who received a single short paclitaxel infusion when compared to patients who did not receive the infusion. Gene ontology analysis indicated that the cholesterol pathway may be dysregulated by paclitaxel in these patients. Validation analysis showed that paclitaxel treatment significantly reduced plasma high-density lipoprotein levels and increased plasma hydroperoxide levels when compared to breast cancer patients without chemotherapy. Furthermore, augmented C-reactive protein and creatine kinase fraction MB were found to be significantly higher in paclitaxel-treated patients in comparison with healthy controls. CONCLUSIONS: Taken together, these data suggest that a single dose of short paclitaxel infusion is sufficient to trigger significant alterations in lipid metabolism, which puts breast cancer patients at risk for increased incidence of cardiovascular disease.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Biomarcadores/sangue , Neoplasias da Mama/tratamento farmacológico , Metabolismo dos Lipídeos/fisiologia , Paclitaxel/uso terapêutico , Doença Aguda , Neoplasias da Mama/patologia , Feminino , Humanos , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia
13.
Colloids Surf B Biointerfaces ; 155: 466-476, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472750

RESUMO

Mineralization of the skeleton starts within cell-derived matrix vesicles (MVs); then, minerals propagate to the extracellular collagenous matrix. Tissue-nonspecific alkaline phosphatase (TNAP) degrades inorganic pyrophosphate (PPi), a potent inhibitor of mineralization, and contributes Pi (Phosphate) from ATP to initiate mineralization. Compared to the plasma membrane, MVs are rich in Cholesterol (Chol) (∼32%) and TNAP, but how Chol influences TNAP activity remains unclear. We have reconstituted TNAP in liposomes of dipalmitoylphosphatidylcholine (DPPC) or dioleoylphosphatidylcholine (DOPC) combined with Chol or its derivatives Cholestenone (Achol) and Ergosterol (Ergo). DPPC plus 36% sterols in liposome increased the catalytic activity of TNAP toward ATP. The presence of Chol also increased the propagation of minerals by 3.4-fold. The catalytic efficiency of TNAP toward ATP was fourfold lower in DOPC proteoliposomes as compared to DPPC proteoliposomes. DOPC proteoliposomes also increased biomineralization by 2.8-fold as compared to DPPC proteoliposomes. TNAP catalyzed the hydrolysis of ATP more efficiently in the case of the proteoliposome consisting of DOPC with 36% Chol. The same behavior emerged with Achol and Ergo. The organization of the lipid and the structure of the sterol influenced the surface tension (γ), the TNAP phosphohydrolytic activity in the monolayer, and the TNAP catalytic efficiency in the bilayers. Membranes in the Lα phase (Achol) provided better kinetic parameters as compared to membranes in the Lo phase (Chol and Ergo). In conclusion, the physical properties and the lateral organization of lipids in proteoliposomes are crucial to control mineral propagation mediated by TNAP activity during mineralization.


Assuntos
Fosfatase Alcalina/metabolismo , Calcificação Fisiológica , Microambiente Celular , Colesterol/química , Minerais/metabolismo , 1,2-Dipalmitoilfosfatidilcolina/química , 1,2-Dipalmitoilfosfatidilcolina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Células Cultivadas , Colestenonas/química , Colestenonas/metabolismo , Colesterol/metabolismo , Difosfatos/química , Difosfatos/metabolismo , Ergosterol/química , Ergosterol/metabolismo , Lipossomos/química , Lipossomos/metabolismo , Masculino , Osteoblastos/citologia , Osteoblastos/metabolismo , Fosfatos/química , Fosfatos/metabolismo , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Ratos Wistar , Propriedades de Superfície
14.
J Adolesc ; 58: 12-23, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28475930

RESUMO

The purpose of this study was to understand how adolescent cybervictims perceive their school climate and whether telling school community members, such as teachers, play a significant role in these perceptions. Another objective was to understand whether age and gender played a significant role in the relation between whom cybervictims told and their perceived school climate. The Cybervictims Scale for Adolescents and Children and the Perceived School Climate Scale were applied to 3525 Portuguese students of whom 218 were cybervictims attending 6th, 8th, and 11th grades. Results showed that even though adolescent cybervictims reported cybervictimization more to friends and parents, those who told teachers about their experience, tended to report more positive perceptions of their school climate. Gender and age did not play a significant role in the relationship between cybervictimization and perceived school climate. Implications of the findings are discussed with regards to the role of teachers and in-service training in preventing cyberbullying.


Assuntos
Bullying , Internet , Estudantes/psicologia , Adolescente , Criança , Feminino , Humanos , Masculino , Grupo Associado , Percepção , Professores Escolares , Instituições Acadêmicas/organização & administração , Inquéritos e Questionários
15.
Lupus ; 26(10): 1106-1111, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28420072

RESUMO

The aims of the present study were to evaluate biomarkers of oxidative and nitrosative stress in systemic lupus erythematosus (SLE) patients, in particular products of DNA/RNA oxidative damage and their correlation with disease activity. This study included 188 controls and 203 patients; 153 with inactive SLE (SLEDAI < 6) and 50 with active SLE (SLEDAI ≥ 6) without renal impairment. Oxidative stress was assessed by tert-butyl hydroperoxide-initiated by chemiluminescence, advanced oxidation protein products (AOPP), total radical-trapping antioxidant parameter (TRAP), nitric oxide metabolites (NOx), and DNA/RNA oxidation products. Patients with SLE showed increased oxidative stress, as demonstrated by the augmentation of lipid hydroperoxides ( p < 0.0001) and AOPP ( p < 0.001) and reduced total antioxidant capacity ( p < 0.0001), without differences between patients with active disease and in remission. NOx levels and DNA/RNA oxidation products were inversely and independently associated with disease activity ( p < 0.0001 and p = 0.021, respectively), regardless of BMI and prednisone use. The linear regression analysis showed that about 5% of the SLEDAI score can be explained by the levels of DNA/RNA oxidation products ( r2:0.051; p = 0.002) and about 9% of this score by the levels of NOx ( r2:0.091; p < 0.0001). This study provides evidence for an inverse association between serum NOx levels and DNA/RNA oxidation products and SLE disease activity, suggesting that oxidative/nitrosative stress markers may be useful in evaluating SLE disease activity and progression of the disease.


Assuntos
Lúpus Eritematoso Sistêmico/fisiopatologia , Óxido Nítrico/metabolismo , Estresse Nitrosativo/fisiologia , Estresse Oxidativo/fisiologia , Adulto , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Estudos de Casos e Controles , DNA/metabolismo , Progressão da Doença , Feminino , Glucocorticoides/uso terapêutico , Humanos , Modelos Lineares , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Oxirredução , Prednisona , RNA/metabolismo , Índice de Gravidade de Doença
17.
Oxid Med Cell Longev ; 2015: 6429812, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26697139

RESUMO

In this paper, we investigated the oxidative profile of breast tumors in comparison with their normal adjacent breast tissue. Our study indicates that breast tumors present enhanced oxidative/nitrosative stress, with concomitant augmented antioxidant capacity when compared to the adjacent normal breast. These data indicate that breast cancers may be responsible for the induction of a prooxidant environment in the mammary gland, in association with enhanced TNF-α and nitric oxide.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Glândulas Mamárias Humanas/patologia , Estresse Oxidativo , Adulto , Idoso , Área Sob a Curva , Mama/metabolismo , Neoplasias da Mama/metabolismo , Cromatografia Líquida de Alta Pressão , Feminino , Homocisteína/análise , Humanos , Peroxidação de Lipídeos , Malondialdeído/análise , Glândulas Mamárias Humanas/metabolismo , Pessoa de Meia-Idade , Óxido Nítrico/análise , Carbonilação Proteica , Curva ROC , Fator de Necrose Tumoral alfa/análise
18.
Phys Chem Chem Phys ; 17(39): 26295-301, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26389140

RESUMO

Tissue-nonspecific alkaline phosphatase (TNAP) plays a crucial role during skeletal mineralization, and TNAP deficiency leads to the soft bone disease hypophosphatasia. TNAP is anchored to the external surface of the plasma membranes by means of a GPI (glycosylphosphatidylinositol) anchor. Membrane-anchored and solubilized TNAP displays different kinetic properties against physiological substrates, indicating that membrane anchoring influences the enzyme function. Here, we used Electron Spin Resonance (ESR) measurements along with spin labeled phospholipids to probe the possible dynamic changes prompted by the interaction of GPI-anchored TNAP with model membranes. The goal was to systematically analyze the ESR data in terms of line shape changes and of alterations in parameters such as rotational diffusion rates and order parameters obtained from non-linear least-squares simulations of the ESR spectra of probes incorporated into DPPC liposomes and proteoliposomes. Overall, the presence of TNAP increased the dynamics and decreased the ordering in the three distinct regions probed by the spin labeled lipids DOPTC (headgroup), and 5- and 16-PCSL (acyl chains). The largest change was observed for 16-PCSL, thus suggesting that GPI-anchored TNAP can give rise to long reaching modifications that could influence membrane processes halfway through the bilayer.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/metabolismo , Fosfatase Alcalina/metabolismo , Lipossomos/metabolismo , Animais , Células CHO , Cricetulus , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Marcadores de Spin
19.
Int Immunopharmacol ; 27(1): 8-14, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25937481

RESUMO

Trastuzumab is an immunotargeting therapeutic against breast tumors with amplification of the human epithelial growth factor receptor 2 (HER2). HER2 patients naturally exhibit disruption in the pro-oxidant inflammatory profiling; however, the impact of trastuzumab-based chemotherapy in modulating this process is still unknown. Here we determined the systemic pro-inflammatory profile of women diagnosed with HER2-amplified tumors, undergoing trastuzumab-based chemotherapy (TZ), and compared the results with that of healthy controls (CTR) and untreated patients with HER2-amplified breast cancer (CA). The plasmatic inflammatory profile was assessed by evaluating pro-oxidant parameters such as lipid peroxidation, total antioxidant capacity (TRAP), levels of advanced oxidation protein products (AOPPs), nitric oxide (NO), C-reactive protein (CRP), and total thiol content. Markers of cardiac damage were also assessed. Our findings showed increased NO levels in TZ than that in either CA or CTR groups. Furthermore, TZ augmented TRAP and reduced total thiol than that of the CA group. Our data also revealed that AOPP levels were significantly higher in the TZ than the CA group. AOPP and the MB fraction of creatine-kinase (CKMB) levels were positively correlated in TZ patients. These findings suggest that trastuzumab-associated chemotherapy can modulate the pro-inflammatory markers of HER2-positive breast cancer patients to the levels found in healthy controls.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal/tratamento farmacológico , Tratamento Farmacológico , Trastuzumab/administração & dosagem , Adulto , Idoso , Antineoplásicos/efeitos adversos , Proteína C-Reativa/metabolismo , Feminino , Homeostase/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Óxido Nítrico/metabolismo , Oxirredução/efeitos dos fármacos , Receptor ErbB-2/metabolismo , Compostos de Sulfidrila/metabolismo , Trastuzumab/efeitos adversos
20.
J Mol Neurosci ; 53(2): 211-21, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24696164

RESUMO

This study evaluated the association of tumor necrosis factor beta (TNF-ß) NcoI polymorphism with the presence of multiple sclerosis (MS), disability, and HLA-DRB1 alleles in 208 Brazilian MS patients. As controls, 147 healthy individuals were included. The disability was evaluated at baseline and 5-year follow-up using the Expanded Disability Status Scale (EDSS). The TNF-ß genotypes were determined using PCR and restriction fragment length polymorphism and serum TNF-α level was determined using enzyme-linked immunosorbent assay. Among the MS patients, 166 (79.8 %) were white, 39 (18.7 %) were brown, and three (1.4 %) were Asian descents (those were excluded from the further analysis). Among the 205 MS patients, 149 (72.6 %) presented remitting-relapsing MS. The baseline and 5-year follow-up EDSS ranged from 0.0 to 3.0 and from 1.0 to 5.7, respectively. The TNFB2/B2 genotype was associated with the presence of MS among the white patients (p = 0.0443). Brown patients presented higher disability (p = 0.0234) and higher TNF-α levels (p = 0.0463) than white patients. White and brown patients carrying TNFB2/B2 genotype exhibited higher TNF-α levels (p = 0.0354 and p = 0.0309, respectively) than those with other geotypes. Association between TNF-ß NcoI genotypes and HLA-DRB1 alleles was not observed among the MS patients (p > 0.05). Taken together, TNFB2 allele was associated with the presence of MS independently of HLA-DRB1 in white patients and the TNFB2/B2 genotype was associated with increased TNF-α levels in white and brown patients, which could be an important genetic factor candidate for the susceptibility and pathogenesis of MS.


Assuntos
Cadeias HLA-DRB1/genética , Linfotoxina-alfa/genética , Esclerose Múltipla/genética , Polimorfismo de Fragmento de Restrição , Adulto , Brasil , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/etnologia , Fator de Necrose Tumoral alfa/sangue , População Branca
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