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HTLV-1-infected individuals may develop a neurologic inflammatory condition known as HTLV-1-associated myelopathy (HAM/TSP), in which the high production of TNF is observed. These patients exhibit higher proviral loads, enhanced production of proinflammatory cytokines and lymphocyte proliferation in comparison to asymptomatic HTLV-1 carriers and those presenting overactive bladder (OAB-HTLV-infected). Metalloproteinases (MMPs) are known to degrade the components of the blood-brain barrier, favoring the migration of infected cells into the central nervous system. Moreover, the unbalanced production of MMPs and their inhibitors (TIMPs) has also been associated with tissue damage. The present work studied the production of MMP-9 and TIMPs in HTLV-1-infected individuals with and without neurological manifestations. HAM/TSP patients presented higher concentrations of MMP-9 in peripheral blood mononuclear cell (PBMC) culture supernatants, as well as a higher MMP-9/TIMP-3 ratio when compared to the other groups studied. MMP-9 levels positively correlated with proviral load and TNF in OAB-HTLV-infected individuals, and the in vitro neutralization of TNF significantly decreased MMP-9 levels in PBMC culture supernatants. Our findings indicate an association between MMP-9 production and the proinflammatory state associated with HTLV-1 infection, as well as HAM/TSP.
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Vírus Linfotrópico T Tipo 1 Humano , Paraparesia Espástica Tropical , Humanos , Leucócitos Mononucleares , Metaloproteinase 9 da Matriz , Provírus , Carga ViralRESUMO
Noncoding microRNAs are involved in lipid and carbohydrate metabolism pathways and are powerful regulators of gene expression. The goals of this study were to evaluate the temporal expression profiles of miRNAs in rat adipose tissue and predict mRNA−microRNA interactions. Newly weaned Wistar rats were divided into groups fed a standard diet and high-sucrose diet (HSD). The HSD contains 66.86% carbohydrates (40.45% standard diet, 40.45% condensed milk, and 8.58% crystal sugar), and the HSD was provided for 4, 8 and 15-week periods to investigate the expression levels of miRNAs in visceral adipose tissue using RT−qPCR. Target selection, enriched pathways and networks were analyzed in silico. The factor consumption time significantly was associated to decreases (p < 0.05) in the expression levels of the following miRNAs: 124-5p, 125-5p, 126-5p, 200c-3p, and 212-3p in all experimental groups. The factor diet significantly influenced rno-miR-124-5p, 200c-3p, and 212-3p expression (p < 0.05). A significant reduction (p < 0.05) in rno-miR-27a-3p expression was observed. The biological processes involved key pathways regulating fat deposition. Our findings provide important insights into downregulated miRNA expression patterns in visceral adipose tissue, adiposity level, hyperinsulinemia and increased VLDL-c and triglyceride levels.
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Sacarose Alimentar , Gordura Intra-Abdominal , MicroRNAs , Animais , Sacarose Alimentar/efeitos adversos , Gordura Intra-Abdominal/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos , Ratos WistarRESUMO
BACKGROUND: Metabolic imprinting describes associations between nutritional experiences of early life and the development of diseases later in life. The goal of this study was to evaluate the metabolic imprinting induced by a high-sugar diet (HSD) and its effects on microRNA (miRNA) expression and insulin resistance (IR) in young rats. We assessed the effects of expression of adipogenic (miR-200c) and metabolic (miR-126a) miRNAs in retroperitoneal white adipose tissue (rWAT) on IR development. METHODS AND RESULTS: Weaned male Wistar rats (N = 6) were fed a standard chow diet or HSD (68% carbohydrates) for 4-, 8-, or 12-weeks. Serum samples were collected to measure triacylglycerol and VLDL-cholesterol, and we assessed glucometabolic parameters (glucose, insulin, HOMA-IR, and QUICKI). rWAT was collected for microRNA analysis (N = 3). The HSD resulted in body fat accretion and IR after 8-weeks, which resolved by 12-weeks. Moreover, the HSD had a time-dependent effect on miRNA relative expression, downregulating rno-miR-200c-3p at week 8 and rno-miR-126a-3p at week 12. CONCLUSIONS: MiR-200 family dysregulation has been related to IR, and miR-126a downregulation could be associated with the improvement in IR observed after a 12-week HSD feeding period. This is the first time that excessive sugar intake post-weaning has been associated with miRNA production by rWAT with an impact on IR development.
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Resistência à Insulina , MicroRNAs , Animais , Dieta , Glucose/metabolismo , Resistência à Insulina/genética , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos , Ratos WistarRESUMO
DNA methylation is an important epigenetic mechanism of gene expression control. The present study aimed to evaluate the temporal effect of isocaloric high-sugar diet (HSD) intake on the development of nonalcoholic fatty liver disease (NAFLD) and the role of DNA methylation in this event. Newly weaned Wistar rats were divided into eight groups and fed a standard chow diet or an HSD ad libitum for 4 weeks, 8 weeks, 15 weeks, and 18 weeks. After the experimental periods, the animals were euthanized and their livers were removed for histological analysis, gene expression of maintenance methylase (Dnmt1), de novo methylases (Dnmt3a and Dnmt3b), demethylases (Tet2 and Tet3) of DNA, and global DNA methylation. HSD intake led to the gradual development of NAFLD. HSD intake for 18 weeks was associated with downregulation of Dnmt1 expression and global DNA hypomethylation; these results were negatively correlated with more severe steatosis scores observed in these animals. The HSD consumption for 18 weeks was also associated with a decrease in Dnmt3a and Tet2 expression. Interestingly, the expression of de novo methyltransferase Dnmt3b was reduced by HSD during all experimental periods. Together, these results indicate that the downregulation of de novo DNA methylation, Dnmt3b, induced by HSD is the primary factor in the development of NAFLD. On the other hand, disease progression is associated with downregulation of maintenance DNA methylation and global DNA hypomethylation. These results suggest a link between the dynamic changes in hepatic DNA methylation and the development of NAFLD induced by an HSD intake.
Assuntos
Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Metilação de DNA , Ratos Wistar , Dieta , DNA , AçúcaresRESUMO
BACKGROUND: Schistosomiasis is a disease caused by Schistosoma. Due to its complex life cycle, evolutionary position and sexual dimorphism, schistosomes have several mechanisms of gene regulation. MicroRNAs (miRNAs) are short endogenous RNAs that regulate gene expression at the post-transcriptional level by targeting mRNA transcripts. OBJECTIVES: Here, we tested 12 miRNAs and identified their putative targets using a computational approach. METHODS: We performed the expression profiles of a set of miRNAs and their putative targets during the parasite's life cycle by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). FINDINGS: Our results showed differential expression patterns of the mature miRNAs sma-miR-250; sma-miR-92a; sma-miR-new_4-3p; sma-miR-new_4-5p; sma-miR-new_5-5p; sma-miR-new_12-5p; sma-miR-new_13-3p and sma-miR-new_13-5p. Interestingly, many of the putative target genes are linked to oxidative phosphorylation and are up-regulated in adult-worms, which led us to suggest that miRNAs might play important roles in the post-transcriptional regulation of genes related to energetic metabolism inversion during parasite development. It is noteworthy that the expression of sma-miR-new_13-3p exhibited a negative correlation on SmNADH:ubiquinone oxidoreductase complex I. MAIN CONCLUSIONS: Our analysis revealed putative miRNA genes related to important biological processes, such as transforming growth factor beta (TGF-ß) signaling, proteasome regulation, glucose and lipid metabolism, immune system evasion and transcriptional regulation.
Assuntos
MicroRNAs , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Estágios do Ciclo de Vida/genética , MicroRNAs/genética , Schistosoma mansoni/genética , Transdução de SinaisRESUMO
The increasing incidence of diseases caused by the harmful effects of UV radiation in skin, predominantly skin cancer, induce the search for more efficient photoprotector agents. Nowadays, titanium dioxide (TiO2) and zinc oxide (ZnO) are the most widely used photoprotectors and therefore form the main components of commercially available sunscreens. Although the outstanding efficiency in absorbing and scattering UV radiation, mainly as nanoparticles, recent studies have raised concerns regarding the safe use of these nanoparticles, especially due to their high generation of reactive oxygen species (ROS). Thereby, this work focus on the evaluation of the photoprotective activity of zirconia nanoparticles (ZrO2 NPs) and their cytotoxicity study in the presence and absence of UV irradiation. The ZrO2 NPs were synthesized by hydrothermal method and their hydrodynamic diameter, Zeta potential and colloidal stability were characterized by dynamic light scattering. The morphology and size were observed by transmission electron microscopy. The synthesis resulted in ZrO2 NPs with 50 nm of diameter and 56 nm of hydrodynamic diameter. The high colloidal stability was evidenced by the high value of Zeta potential (+48 mV) and low polydispersity index (0.09). The UV-vis spectrum of the ZrO2 NPs in aqueous suspension showed an intense light scattering below 250 and a wide absorption band at 285 nm. The poor generation of ROS by ZrO2 NPs was confirmed by the absence of photodegradation of methylene blue after long periods of irradiation. The in vitro assays performed with HaCaT cell line showed that the cell viability did not decrease in the absence of irradiation. However, after 24 h of incubation, the cell viability decreased under UV-irradiation in comparison with irradiated cells that were not incubated with ZrO2 NPs. Notably, in these assays, the cells were incubated with the ZrO2 NPs and after 24 h, they were replaced by fresh culture medium before the cell viability assay. Nevertheless, another in vitro assay was performed in order to evaluate the photoprotective activity of ZrO2 NPs. The cells were irradiated in the presence of ZrO2 NPs suspension. In this case, cell viability did not decrease even after long period of UV-irradiation and at higher concentration of ZrO2 NPs. The present results showed that ZrO2 NPs could be an interesting material to be used for skin photoprotection since they showed low cytotoxicity, absence of ROS generation and protection under UV irradiation. Additionally, the ZrO2 NPs suspension was transparent as usually required for applications in sunscreens.
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Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Raios Ultravioleta , ZircônioRESUMO
Long non-coding RNAs (lncRNAs) perform several types of regulatory functions and have been recently explored in the genus Schistosoma. Although sequencing and bioinformatics approaches have demonstrated the presence of hundreds of lncRNAs and microRNAs (miRNAs) in this genus, information regarding their abundance, characteristics, and potential functions linked to Schistosoma mansoni biology and parasite-host interaction is limited. Our objectives in the present study were to verify whether 15 previously identified S. mansoni lncRNAs are detectable in the host liver. In addition, we assess whether these lncRNAs are present in the S. mansoni infective form and the stages inside the definitive host. The detection of these 15 S. mansoni lncRNAs and a long terminal repeat (LTR) retrotransposon Saci 4 was performed in the eggs, cercariae, and 3.5-h schistosomula. All lncRNAs were found to be expressed in these stages; some of the lncRNAs were found in the livers of the infected C57BL/6 mice. In conclusion, S. mansoni lncRNAs were detected in host livers and quantified. Furthermore, many of the lncRNAs analyzed showed differential expression in the larval stages, indicating that they play a stage-specific regulatory role.
Assuntos
Fígado/parasitologia , RNA Longo não Codificante/isolamento & purificação , Schistosoma mansoni/genética , Esquistossomose mansoni/parasitologia , Animais , Mapeamento Cromossômico , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , Retroelementos/fisiologia , Transcrição Reversa , Schistosoma mansoni/crescimento & desenvolvimento , Schistosoma mansoni/isolamento & purificação , Esquistossomose mansoni/patologiaRESUMO
BACKGROUND Schistosomiasis is a disease caused by Schistosoma. Due to its complex life cycle, evolutionary position and sexual dimorphism, schistosomes have several mechanisms of gene regulation. MicroRNAs (miRNAs) are short endogenous RNAs that regulate gene expression at the post-transcriptional level by targeting mRNA transcripts. OBJECTIVES Here, we tested 12 miRNAs and identified their putative targets using a computational approach. METHODS We performed the expression profiles of a set of miRNAs and their putative targets during the parasite's life cycle by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). FINDINGS Our results showed differential expression patterns of the mature miRNAs sma-miR-250; sma-miR-92a; sma-miR-new_4-3p; sma-miR-new_4-5p; sma-miR-new_5-5p; sma-miR-new_12-5p; sma-miR-new_13-3p and sma-miR-new_13-5p. Interestingly, many of the putative target genes are linked to oxidative phosphorylation and are up-regulated in adult-worms, which led us to suggest that miRNAs might play important roles in the post-transcriptional regulation of genes related to energetic metabolism inversion during parasite development. It is noteworthy that the expression of sma-miR-new_13-3p exhibited a negative correlation on SmNADH:ubiquinone oxidoreductase complex I. MAIN CONCLUSIONS Our analysis revealed putative miRNA genes related to important biological processes, such as transforming growth factor beta (TGF-β) signaling, proteasome regulation, glucose and lipid metabolism, immune system evasion and transcriptional regulation.
Assuntos
Animais , MicroRNAs/genética , Schistosoma mansoni/genética , Transdução de Sinais , Regulação da Expressão Gênica/genética , Perfilação da Expressão Gênica , Estágios do Ciclo de Vida/genéticaRESUMO
Scientific advances in recent decades have revealed an incredible degree of plasticity in gene expression in response to various environmental, nutritional, physiological, pathological, and behavioral conditions. Epigenetics emerges in this sense, as the link between the internal (genetic) and external (environmental) factors underlying the expression of the phenotype. Methylation of DNA and histone post-translationa modifications are canonical epigenetic events. Additionally, noncoding RNAs molecules (microRNAs and lncRNAs) have also been proposed as another layer of epigenetic regulation. Together, these events are responsible for regulating gene expression throughout life, controlling cellular fate in both normal and pathological development. Despite being a relatively recent science, epigenetics has been arousing the interest of researchers from different segments of the life sciences and the general public. This review highlights the recent advances in the characterization of the epigenetic events and points promising use of these brands for the diagnosis, prognosis, and therapy of diseases. We also present several classes of epigenetic modifying compounds with therapeutic applications (so-call epidrugs) and their current status in clinical trials and approved by the FDA. In summary, hopefully, we provide the reader with theoretical bases for a better understanding of the epigenetic mechanisms and of the promising application of these marks and events in the medical clinic.
Assuntos
Biomarcadores/metabolismo , Metilação de DNA , Desenvolvimento de Medicamentos/métodos , Epigênese Genética , Código das Histonas , Animais , Regulação da Expressão Gênica , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genéticaRESUMO
Objective Provide a comprehensive view of the events surrounding the sugar consumption, under conditions of energy equivalence; through the analysis of behavioral aspects of intake, and of biochemical, metabolic and physiological parameters, as well as the effect of this nutrient on the plasticity of adipose tissue. Materials and methods Newly weaned male Wistar rats were classified in two groups and subjected to the following normocaloric diets: standard chow diet or to high-sugar diet (HSD) ad libitum for 18 weeks. Results The animals submitted to the HSD were associated with a lower caloric intake during the 18 weeks of experimentation. However, the HSD induced a significant increase in body weight, white adipose tissue weight, adiposity index, Lee index, and the levels of triglycerides and very low-density lipoprotein in the serum. In addition, it induced glucose intolerance, insulin resistance and compensatory increase of insulin secretion by pancreatic ß-cells. Also increased heart rate and induced hyperplasia, and hypertrophy of retroperitoneal visceral adipose tissue. In the liver, the HSD was associated with increased hepatic lipid content (i.e., triglycerides and cholesterol) and hepatomegaly. Conclusion The post-weaning consumption of HSD induces an adaptive response in metabolism; however, such an event is not enough to reverse the homeostatic imbalance triggered by the chronic consumption of this macronutrient, leading to the development of metabolic syndrome, irrespective of caloric intake. These findings corroborate recent evidence indicating that sugar is a direct contributor to metabolic diseases independent of a positive energy balance. Arch Endocrinol Metab. 2020;64(1):71-81.
Assuntos
Tecido Adiposo/metabolismo , Açúcares da Dieta/metabolismo , Ingestão de Energia , Metabolismo Energético , Doenças Metabólicas/metabolismo , Obesidade/metabolismo , Animais , Açúcares da Dieta/efeitos adversos , Açúcares da Dieta/sangue , Masculino , Doenças Metabólicas/sangue , Obesidade/sangue , Obesidade/etiologia , Ratos , Ratos WistarRESUMO
Recently, there has been an increasing interest in the use of yeast to produce biosorbent materials, because yeast is economical to use, adaptable to a variety of conditions, and amenable to morphological manipulations to yield better raw biomaterials. Previous studies from our laboratory have shown that Meyerozyma guilliermondii, a non-pathogenic haploid yeast (ascomycete), exhibits excellent biosorption capacity for Mn2+, as demonstrated by kinetic analyses. Shotgun/bottom-up analyses of soluble fractions revealed a total of 1257 identified molecules, with 117 proteins expressed in the absence of Mn2+ and 69 expressed only in the presence of Mn2+. In this article, we describe the first in silico prediction and screening of protein-protein interactions (PPIs) in M. guilliermondii using experimental data from shotgun/bottom-up analyses. We also present the categorization of biological processes (BPs), molecular functions (MFs), and metabolic pathways of 71 proteins upregulated in the M. guilliermondii proteome in response to stress caused by an excess of Mn2+ ions. Most of the annotated proteins were related to oxidation-reduction processes, metabolism, and response to oxidative stress. We identified seven functional enrichments and 42 metabolic pathways; most proteins belonged to pathways related to metabolic pathways (19 proteins) followed by the biosynthesis of secondary metabolites (10 proteins) in the presence of Mn2+. Using our data, it is possible to infer that defense mechanisms minimize the impact of Mn2+ via the expression of antioxidant proteins, thus allowing adjustment during the defense response. Previous studies have not considered protein interactions in this genus in a manner that permits comparisons. Consequently, the findings of the current study are innovative, highly relevant, and provide a description of interactive complexes and networks that yield insight into the cellular processes of M. guilliermondii. Collectively, our data will allow researchers to explore the biotechnological potential of M. guilliermondii in future bioremediation processes.
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Schistosoma mansoni adaptive success is related to regulation of replication, transcription and translation inside and outside the intermediate and definitive host. We hypothesize that S. mansoni alters its epigenetic state in response to the mammalian host immune system, reprogramming gene expression and altering the number of eggs. In response, a change in the DNA methylation profile of hepatocytes could occurs, modulating the extent of hepatic granuloma. To investigate this hypothesis, we used the EBi3-/- murine (Mus musculus) model of S. mansoni infection and evaluated changes in new and maintenance DNA methylation profiles in the liver after 55 days of infection. We evaluated expression of epigenetic genes and genes linked to histone deubiquitination in male and female S. mansoni worms. Comparing TET expression with DNMT expression indicated that DNA demethylation exceeds methylation in knockout infected and uninfected mice and in wild-type infected and uninfected mice. S. mansoni infection provokes activation of demethylation in EBi3-/-I mice (knockout infected). EBi3-/-C (knockout uninfected) mice present intrinsically higher DNA methylation than WTC (control uninfected) mice. EBi3-/-I mice show decreased hepatic damage considering volume and reduced number of granulomas compared to WTI mice; the absence of IL27 and IL35 pathways decreases the Th1 response resulting in minor liver damage. S. mansoni males and females recovered from EBi3-/-I mice have reduced expression of a deubiquitinating enzyme gene, orthologs of which target histones and affect chromatin state. SmMBD and SmHDAC1 expression levels are downregulated in male and female parasites recovered from EBi3-/-, leading to epigenetic gene downregulation in S. mansoni. Changes to the immunological background thus induce epigenetic changes in hepatic tissues and alterations in S. mansoni gene expression, which attenuate liver symptoms in the acute phase of schistosomiasis.
Assuntos
Epigênese Genética , Antígenos de Histocompatibilidade Menor/genética , Receptores de Citocinas/genética , Esquistossomose mansoni/imunologia , Animais , Metilação de DNA , Feminino , Regulação da Expressão Gênica/imunologia , Fígado/metabolismo , Fígado/parasitologia , Masculino , Camundongos , Camundongos Knockout , MicroRNAs , RNA de Helmintos/genética , RNA de Helmintos/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Schistosoma mansoni/imunologia , Esquistossomose mansoni/parasitologiaRESUMO
Manganese (Mn) is toxic at higher concentrations requiring its removal before returning the wastewater to the environment. This article reported the Mn removal of two fungi strains isolated from mine wastewater. ITS rRNA region sequencing identified the fungi strains as Cladosporium halotolerans and Hypocrea jecorina.â¯Mn2+ removal assays were performed in Sabouraud broth with 50â¯mgâ¯L-1â¯Mn2+ supplemented and bioleaching assays using MnO2 instead of MnSO4 at the same conditions. C. halotolerans removed 96 % of 50â¯mgâ¯L-1â¯Mn2+ at two weeks without MnO2 bioleaching with 649.9â¯mg of biomass and H. jecorina removed about 50 % of Mn2+ in 21 days from initial 50â¯mg of Mn2+ L-1 with 316.8â¯mg of biomass. Extracellular laccases were present in C. halotolerans agar regardless of the Mn addition. Mn adsorbed was detected on C. halotolerans hyphae. Mn oxidation was positive to H. jecorina by reaction of its medium with Leucoberbelin blue.
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ABSTRACT Objective Provide a comprehensive view of the events surrounding the sugar consumption, under conditions of energy equivalence; through the analysis of behavioral aspects of intake, and of biochemical, metabolic and physiological parameters, as well as the effect of this nutrient on the plasticity of adipose tissue. Materials and methods Newly weaned male Wistar rats were classified in two groups and subjected to the following normocaloric diets: standard chow diet or to high-sugar diet (HSD) ad libitum for 18 weeks. Results The animals submitted to the HSD were associated with a lower caloric intake during the 18 weeks of experimentation. However, the HSD induced a significant increase in body weight, white adipose tissue weight, adiposity index, Lee index, and the levels of triglycerides and very low-density lipoprotein in the serum. In addition, it induced glucose intolerance, insulin resistance and compensatory increase of insulin secretion by pancreatic β-cells. Also increased heart rate and induced hyperplasia, and hypertrophy of retroperitoneal visceral adipose tissue. In the liver, the HSD was associated with increased hepatic lipid content (i.e., triglycerides and cholesterol) and hepatomegaly. Conclusion The post-weaning consumption of HSD induces an adaptive response in metabolism; however, such an event is not enough to reverse the homeostatic imbalance triggered by the chronic consumption of this macronutrient, leading to the development of metabolic syndrome, irrespective of caloric intake. These findings corroborate recent evidence indicating that sugar is a direct contributor to metabolic diseases independent of a positive energy balance. Arch Endocrinol Metab. 2020;64(1):71-81
Assuntos
Animais , Masculino , Ratos , Ingestão de Energia , Tecido Adiposo/metabolismo , Metabolismo Energético , Açúcares da Dieta/metabolismo , Doenças Metabólicas/metabolismo , Obesidade/metabolismo , Ratos Wistar , Açúcares da Dieta/efeitos adversos , Açúcares da Dieta/sangue , Doenças Metabólicas/sangueRESUMO
This study evaluated the effect of 10% sodium hypochlorite (NaOCl) as deproteinizing agent and storage media on bond strength (BS) of two etch-and-rinse adhesive systems to dentin. Twenty-eight sound extracted human third molars were divided in four groups (n = 7), according to dentin treatment (conventional etching or etching followed by 10% NaOCl application) and adhesive systems (GB-Gluma 2Bond and OS-One-Step). After dentin treatments and adhesive application, a composite block was built-up on dentin surface and teeth were serially sectioned to obtain bonded sticks specimens. The sticks were submitted to three aging conditions: (24H) 24 hr in water (immediate), (SH) 3 hr of NaOCl accelerated-aging or (1Y) 1 year of water storage. Afterward, submitted to microtensile bond strength test (µTBS), failure modes and adhesive interfaces analyzes. Data were analyzed by two-way analysis of variance (ANOVA) and Tukey's test (α = .05). Dentin deproteinization before bonding significantly reduced µTBS for GB-treated group (p < .05), regardless the aging conditions. Water storage for 1 year (1Y) and NaOCl accelerated-aging (SH) decreased µTBS for both adhesives. Yet, the groups stored in NaOCl (SH) exhibited the lowest BS results (p < .05). Bond strength of deproteinized dentin was dependent on the adhesive system composition and NaOCl accelerated-aging promoted decreased bond strength and further degradation than water storage for 1 year.
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Adesivos/química , Dentina/química , Dente Serotino , Hipoclorito de Sódio/química , Colagem Dentária , Análise do Estresse Dentário , Humanos , Teste de Materiais , Resistência à Tração , ÁguaRESUMO
Aim: Evaluate the effect of adhesives systems combined with desensitizer agents on the microtensile bond strength (µTBS) of a composite resin to dentin. Methods: Cervical dentin of thirty-two human molars were used to simulate hypersensitivity areas. The teeth were divided into four groups (n=8), according to the type of adhesive system and desensitizer agents. No desensitizer was used in the control (Clearfil SE Bond CS). Two experimental groups were pretreated with either MS Coat Bond (MS) or Biofluorid 12 (BF) immediately prior to bonding with CS. The last group corresponded to Gluma Comfort Bond + Desensitizer (GC) application. After dentin treatments, a composite block was built-up on dentin surface and after 24 hours teeth were serially sectioned to obtain bonded bean specimens. Beams were stored in water for 24 hours or one year. Subsequently, the specimens were submitted to the µTBS test. Data were analyzed by two-way mixed ANOVA and Bonferroni's test (α = 0.05). Results: At 24 hours, there was no significant difference in µTBS among groups. However, at one year, dentin treated with MS or BF demonstrated significantly lower µTBS of CS to dentin compared to control and GC, which kept their µTBS stable. Conclusion: The effect of MS and BF desensitizer agents on the µTBS of CS to dentin did not reduce the µTBS at 24 hours, but it decreases significantly after one year
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Fluoreto de Cálcio , Ácido Oxálico , Sensibilidade da Dentina , Dessensibilizantes DentináriosRESUMO
In prevention studies of metabolic syndrome (MetS), Ang-(1-7) has shown to improve the insulin signaling. We evaluated the HPßCD/Ang-(1-7) treatment on lipid metabolism, renin-angiotensin system (RAS) components, oxidative stress, and insulin pathway in the liver and gastrocnemius muscle and hepatic steatosis in rats with established MetS. After 7 weeks of high-fat (FAT) or control (CT) diets, rats were treated with cyclodextrin (HPßCD) or HPßCD/Ang-(1-7) in the last 6 weeks. FAT-HPßCD/empty rats showed increased adiposity index and body mass, gene expression of ACE/ANG II/AT1R axis, and oxidative stress. These results were accompanied by imbalances in the insulin pathway, worsening of liver function, hyperglycemia, and dyslipidemia. Oral HPßCD/Ang-(1-7) treatment decreased ACE and AT1R, increased ACE2 gene expression in the liver, and restored thiobarbituric acid reactive substances (TBARS), catalase (CAT), superoxide dismutase (SOD), insulin receptor substrate (Irs-1), glucose transporter type 4 (GLUT4), and serine/threonine kinase 2 (AKT-2) gene expression in the liver and gastrocnemius muscle improving hepatic function, cholesterol levels, and hyperglycemia in MetS rats. Overall, HPßCD/Ang-(1-7) treatment restored the RAS components, oxidative stress, and insulin signaling in the liver and gastrocnemius muscle contributing to the establishment of blood glucose and lipid homeostasis in MetS rats.
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Angiotensina I/farmacologia , Antioxidantes/farmacologia , Síndrome Metabólica/patologia , Fragmentos de Peptídeos/farmacologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Administração Oral , Enzima de Conversão de Angiotensina 2 , Animais , Catalase/genética , Catalase/metabolismo , Ciclodextrinas/farmacologia , Dieta Hiperlipídica , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Síndrome Metabólica/metabolismo , Síndrome Metabólica/veterinária , Músculo Esquelético/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Ratos , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismoRESUMO
PURPOSE: The aim of this study was to evaluate the influence of indirect restorative material type and thickness on the transmission of different wavelengths from a broad-banded dental curing light. METHODS: Four dental indirect restorative materials for computer-aided design and computer-aided manufacturing (CAD/CAM) were evaluated: [RC] resin/ceramic hybrid material (Lava Ultimate), [FC] feldspathic ceramic (VitaBlocs), and two zirconia-based ceramics ([ZK] Katana; and [ZL] Lava). Total loss of irradiance (TL) was measured for blue (WB, 425-490nm) and violet (WV, 350-425nm) wavelengths. Specimens of 15×15mm with varying thicknesses (0.5, 1.0, 1.5, and 2.0mm) were fabricated (n=5). A plasma-arc dental light-curing unit was used (Arc Light-II). To assess TL as a function of wavelength, a software (Spectra Suite v5.1) connected to a spectroradiometer (USB2000) and an integrating sphere (CTSM-LSM-60-SF) was used. Data was subjected to statistical analysis (two-way ANOVA and post-hoc Tukey test, α=0.05). RESULTS: A 0.5mm interposition resulted in TL from 50.5 to 67.2%, depending on material. Increased thickness resulted in higher TL for all materials. FC showed less TL compared to ZK. In general, WV showed higher TL than did WB, and WV/WB proportion decreased with increasing thickness. CONCLUSIONS: Indirect materials significantly reduced TL, and this effect is greater with increasing thickness. WV showed lower penetration compared to WB.
Assuntos
Materiais Dentários , Cura Luminosa de Adesivos Dentários , Luz , Teste de Materiais , Cerâmica , Resinas Compostas , Desenho Assistido por Computador , Polimerização , Cimentos de Resina , ZircônioRESUMO
OBJECTIVE: Angiotensin (Ang)-(1-7) has preventive effects on metabolic syndrome (MetS). The aim of this study was to evaluate the therapeutic effect of oral Ang-(1-7) on mean arterial pressure (MAP), insulin resistance (IR), inflammatory process, and remodeling of white adipose tissue (WAT) in rats with established MetS. METHODS: Rats were subjected to control (CT; AIN-93M) or high-fat (HF) diets for 13 wk to induce MetS and treated with Ang-(1-7) or vehicle (V) for the last 6 wk. At the end of 13 wk, MAP, biochemical and histological parameters, and uncoupling protein (UCP) and inflammatory gene expression were determined by quantitative reverse transcription polymerase chain reaction. RESULTS: HF-V rats showed increased visceral fat deposition, inflammatory cytokine expression, hyperplasia, and hypertrophy in retroperitoneal (WAT) and brown adipose tissue (BAT). Additionally, the gastrocnemius muscle reduced UCP-3 and increased the UCP-1 expression in BAT. HF-V also elevated levels of plasma insulin, glucose, homeostatic model assessment (HOMA) of IR and HOMA-ß, and increased body mass, adiposity, and MAP. Ang-(1-7) treatment in rats with MetS [HF-Ang-(1-7)] reduced WAT area, number of adipocytes, and expression of proinflammatory adipokines in WAT and BAT and increased UCP-3 in gastrocnemius muscle and UCP-1 expression in BAT compared with the HF-V group. These events prevented body mass gain, reduced adiposity, and normalized fasting plasma glucose, insulin levels, HOMA-IR, HOMA-ß, and MAP. CONCLUSION: Data from the present study demonstrated that oral Ang-(1-7) treatment is effective in restoring biochemical parameters and hypertension in established MetS by improving hypertrophy and hyperplasia in WAT and inflammation in adipose tissue, and regulating metabolic processes in the gastrocnemius muscle and BAT.
RESUMO
Organisms, in general, respond to environmental stress by altering their pattern of protein expression (proteome), as an alternative to growing in stressful conditions. A strain of Meyerozyma guilliermondii resistant to manganese was isolated from a sample of water collected from mine drainage in southeastern Minas Gerais (Brazil), and demonstrated manganese detoxification capacity. Protein extracts containing the soluble fractions were obtained after growth of the strain in the absence and presence of MnSO4. Tryptic peptides recovered from samples were analyzed by liquid chromatography coupled to mass spectrometry (LC-MS/MS). Shotgun/bottom-up analyses of the soluble fractions revealed a total of 1257 identified molecules. Treatment with Mn did not affect the growth of yeast but induced changes in the protein profile, with 117 proteins expressed in the absence of Mn and 69 expressed only in its presence. Most of these are annotated as related to DNA repair, oxidoreductase activity, and remodeling of gene expression. This is the first proteomic report of M. guilliermondii, with promising characteristics for Mn bioremediation, and the first of the genus Meyerozyma. This proteomic characterization may help in the understanding of molecular regulatory mechanisms associated with tolerance to excess Mn, and the potential use of biomass in bioremediation processes. SIGNIFICANCE: Environmental pollution by heavy metals such as manganese (Mn2+) has increased as it is a by-product of the mining industry and a potential environmental contaminant. Many studies have explored the use of bacteria for manganese bioremediation, but yeasts have emerged as a promising alternative, displaying faster growth and greater removal efficiency. Previous works of our laboratory showed that Meyerozyma guilliermondii, a non-pathogenic haploid yeast (ascomycete), has excellent removal and accumulation capacity of Mn2+, potentially useful in bioremediation. Nowadays efforts have been devoted to understanding the physiology of metal hyperaccumulation to gain insights into the molecular basis of hyperaccumulation. To obtain a comprehensive understanding of the molecular mechanism of Mn2+ hyperaccumulation in M. guilliermondii, proteomic approaches were employed yielding the first compositional proteomic map of total soluble proteins and their differential expression in the presence of Mn2+. We believe our findings are of biotechnological interest concerning the utilization of M. guilliermondii for bioremediation purposes.