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1.
Materials (Basel) ; 16(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37176314

RESUMO

Nonlinear piezoelectric materials are raised as a great replacement for devices that require low power consumption, high sensitivity, and accurate transduction, fitting with the demanding requirements of new technologies such as the Fifth-Generation of telecommunications (5G), the Internet of Things (IoT), and modern radio frequency (RF) applications. In this work, the state equations that correctly predict the nonlinear piezoelectric phenomena observed experimentally are presented. Furthermore, we developed a fast methodology to implement the state equations in the main FEM simulation software, allowing an easy design and characterization of this type of device, as the symmetry structures for high-order tensors are shown and explained. The operation regime of each high-order tensor is discussed and connected with the main nonlinear phenomena reported in the literature. Finally, to demonstrate our theoretical deductions, we used the experimental measurements, which presented the nonlinear effects, which were reproduced through simulations, obtaining maximum percent errors for the effective elasticity constants, relative effective permittivity, and resonance frequencies of 0.79%, 2.9%, and 0.3%, respectively, giving a proof of the potential of the nonlinear state equations presented for the unifying of all nonlinear phenomena observed in the piezoelectric devices.

2.
Eur J Clin Nutr ; 74(9): 1345-1353, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32404903

RESUMO

BACKGROUND/OBJECTIVES: We aimed to investigate the effects of short-term hypocaloric diet-induced weight loss on DNA methylation profile in leukocytes from women with severe obesity. METHODS: Eleven women with morbid obesity (age: 36.9 ± 10.3 years; BMI: 58.5 ± 10.5 kg/m2) were assessed before and after 6 weeks of a hypocaloric dietary intervention. The participants were compared with women of average weight and the same age (age: 36.9 ± 11.8 years; BMI: 22.5 ± 1.6 kg/m2). Genome-wide DNA methylation analysis was performed in DNA extracted from peripheral blood leukocytes using the Infinium Human Methylation 450 BeadChip assay. Changes (Δß) in the methylation level of each CpGs were calculated. A threshold with a minimum value of 10%, p < 0.001, for the significant CpG sites based on Δß and a false discovery rate of <0.05 was set. RESULTS: Dietary intervention changed the methylation levels at 16,064 CpG sites. These CpGs sites were related to cancer, cell cycle-related, MAPK, Rap1, and Ras signaling pathways. However, regardless of hypocaloric intervention, a group of 878 CpGs (related to 649 genes) remained significantly altered in obese women when compared with normal-weight women. Pathway enrichment analysis identified genes related to the cadherin and Wnt pathway, angiogenesis signaling, and p53 pathways by glucose deprivation. CONCLUSION: A short-term hypocaloric intervention in patients with severe obesity partially restored the obesity-related DNA methylation pattern. Thus, the full change of obesity-related DNA methylation patterns could be proportional to the weight-loss rate in these patients after dietary interventions.


Assuntos
Metilação de DNA , Obesidade Mórbida , Adulto , Dieta Redutora , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/genética , Obesidade Mórbida/genética , Redução de Peso/genética
3.
Sci Rep ; 10(1): 6515, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32296077

RESUMO

DNA methylation could provide a link between environmental, genetic factors and weight control and can modify gene expression pattern. This study aimed to identify genes, which are differentially expressed and methylated depending on adiposity state by evaluating normal weight women and obese women before and after bariatric surgery (BS). We enrolled 24 normal weight (BMI: 22.5 ± 1.6 kg/m2) and 24 obese women (BMI: 43.3 ± 5.7 kg/m2) submitted to BS. Genome-wide methylation analysis was conducted using Infinium Human Methylation 450 BeadChip (threshold for significant CpG sites based on delta methylation level with a minimum value of 5%, a false discovery rate correction (FDR) of q < 0.05 was applied). Expression levels were measured using HumanHT-12v4 Expression BeadChip (cutoff of p ≤ 0.05 and fold change ≥2.0 was used to detect differentially expressed probes). The integrative analysis of both array data identified four genes (i.e. TPP2, PSMG6, ARL6IP1 and FAM49B) with higher methylation and lower expression level in pre-surgery women compared to normal weight women: and two genes (i.e. ZFP36L1 and USP32) that were differentially methylated after BS. These methylation changes were in promoter region and gene body. All genes are related to MAPK cascade, NIK/NF-kappaB signaling, cellular response to insulin stimulus, proteolysis and others. Integrating analysis of DNA methylation and gene expression evidenced that there is a set of genes relevant to obesity that changed after BS. A gene ontology analysis showed that these genes were enriched in biological functions related to adipogenesis, orexigenic, oxidative stress and insulin metabolism pathways. Also, our results suggest that although methylation plays a role in gene silencing, the majority of effects were not correlated.


Assuntos
Adiposidade/genética , Cirurgia Bariátrica , Metilação de DNA , Obesidade/genética , Transcriptoma , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Aminopeptidases/genética , Aminopeptidases/metabolismo , Fator 1 de Resposta a Butirato/genética , Fator 1 de Resposta a Butirato/metabolismo , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Obesidade/metabolismo , Obesidade/cirurgia , Período Pós-Operatório , Período Pré-Operatório , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
4.
BMC Med Genomics ; 12(1): 72, 2019 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-31133015

RESUMO

BACKGROUND/OBJECTIVES: Obesity has been associated with gene methylation regulation. Recent studies have shown that epigenetic signature plays a role in metabolic homeostasis after Roux-en Y gastric bypass (RYGB). To conduct a genome-wide epigenetic analysis in peripheral blood to investigate whether epigenetic changes following RYGB stem from weight loss or the surgical procedure per se. SUBJECTS/METHODS: By means of the Infinium Human Methylation 450 BeadChip array, global methylation was analyzed in blood of 24 severely obese women before and 6 months after RYGB and in 24 normal-weight women (controls). RESULTS: In blood cells, nine DMCpG sites showed low methylation levels before surgery, methylation levels increased after RYGB and neared the levels measured in the controls. Additionally, 44 CpG sites associated with the Wnt and p53 signaling pathways were always differently methylated in the severely obese patients as compared to the controls and were not influenced by RYGB. Finally, 1638 CpG sites related to inflammation, angiogenesis, and apoptosis presented distinct methylation in the post-surgery patients as compared to the controls. CONCLUSION: Bariatric surgery per se acts on CpGs related to inflammation, angiogenesis, and endothelin-signaling. However, the gene cluster associated with obesity remains unchanged, suggesting that weight loss 6 months after RYGB surgery cannot promote this effect.


Assuntos
Metilação de DNA , Epigênese Genética , Derivação Gástrica , Adulto , Peso Corporal/genética , Ilhas de CpG/genética , Feminino , Humanos , Masculino , Obesidade/genética , Obesidade/cirurgia , Fenótipo , Fatores de Tempo
7.
Neurogastroenterol Motil ; 28(7): 994-1000, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26914655

RESUMO

BACKGROUND: The cost-effectiveness for screening for celiac disease (CD) in patients with irritable bowel syndrome (IBS), specifically in the diarrhea (IBS-D) subtype, is beneficial if the prevalence is >1%. However, recent studies have shown controversial results. In this large case-control study, our aim was to determine the prevalence of CD and a panel of related antibodies in patients diagnosed with IBS. MATERIALS AND METHODS: Four hundred IBS patients (Rome III) and 400 asymptomatic healthy controls were prospectively evaluated using antihuman tissue transglutaminase (h-tTG IgA) and deamidated gliadin peptide antibodies (DGP II IgA and DGP II IgG). Duodenal biopsy was performed on the patients that were positive for the h-tTG IgA and/or DGP II IgG antibodies. RESULTS: The mean age of the population was 44.47 ± 18.01 years and 335 (82%) of the subjects were women. Twenty-one patients and six controls had at least one positive test for CD (5.25% VS 1.5%, p = 0.003, OR 3.63 [95% CI 1.4-9.11]). Eighteen patients were positive for h-tTG and/or DGP-II IgG. Histologic confirmation of CD was 2.5% in the IBS patients vs 0.5% in the controls (p = 0.04, OR 5.21). The IBS-D subtype had the highest prevalence for serological positivity (12.7%). CONCLUSIONS: Up to 5.2% of the patients with IBS according to the Rome III criteria were positive for at least one of the CD-related antibodies and 2.5% had biopsy-confirmed CD. Therefore, in our population, screening for CD in subjects with IBS appears to be a reasonable strategy, especially in the IBS-D subgroup.


Assuntos
Autoanticorpos/sangue , Doença Celíaca/sangue , Doença Celíaca/epidemiologia , Síndrome do Intestino Irritável/sangue , Síndrome do Intestino Irritável/epidemiologia , Adulto , Estudos de Casos e Controles , Doença Celíaca/classificação , Feminino , Humanos , Imunoglobulina A/sangue , Síndrome do Intestino Irritável/classificação , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos
8.
Water Sci Technol ; 71(2): 211-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25633944

RESUMO

Biogas produced in municipal and industrial wastewater treatment facilities (BWWF) is a resource wasted in several socio-economic contexts. BWWF-based projects are compared against energy projects using conventional electricity or natural gas (NG), following strict economic considerations that usually tip the balance in favour of conventional energy supply. This is because the economic gain associated with the environmental benefits of using small biogas sources like BWWF does not overcome the technical and financial effort required in these types of project. This paper shows a broader application of life cycle assessment (LCA) methodology to explore opportunities for positive (or effective) utilization of BWWF in the Colombian context. LCA has been used to evaluate the supply-chain of NG which is the direct competitor of BWWF, in three different Colombian regions, in order to identify those where higher NG environmental impacts offer increased environmental added-value to BWWF use. LCA was also applied to study two BWWF valorization scenarios in the poultry processing industry. It shows how valorization options for BWWF are more realistic and effective when specific-regional loads are applied to the environmental assessment of NG supply-chain and BWWF valorization.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Resíduos/análise , Águas Residuárias/química , Biotecnologia/instrumentação , Colômbia , Meio Ambiente
9.
Water Sci Technol ; 69(1): 217-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24434990

RESUMO

Characterization and evaluation of a biological submerged filter was carried out on a full-scale pilot plant performing removal of biochemical oxygen demand (BOD) and total nitrogen (TN) from pre-treated urban wastewater. The average influent values of BOD5, chemical oxygen demand (COD) and TN were 370, 1,015 and 60 mg/L, respectively. The pilot plant produced good discharge quality during steady-state operation. Average effluent BOD5, COD and TN values were 11, 58 and 15 mg/L, respectively. The reactor had been operating beyond its organic design capacity (200 population equivalent (PE)). At 480 PE the removal achieved for BOD, COD and TN were 98, 97 and 78%, respectively. This technology can absorb pollutant overloads while maintaining stable performance. Denitrification was performed by using sewage itself as carbon source. It was used as an intermittent aeration cycle in the unaerated cell to improve the denitrification process. The predenitrification with submerged unaerated filter has proved to be an efficient process for advanced removal of TN.


Assuntos
Carbono/química , Filtração/métodos , Nitrogênio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química
10.
Water Sci Technol ; 62(9): 1998-2008, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21045324

RESUMO

This paper presents the experimental validation and the application to a real industrial catchment of a two-dimensional depth-averaged shallow water model used for the computation of rainfall-runoff transformation from direct precipitation data. Instead of using the common approach in flood inundation modelling, which consists in computing the water depth and velocity fields given the water discharge, in this study the rainfall intensity is imposed directly in the model, the surface runoff being generated automatically. The model considers infiltration losses simultaneously with flow simulation. Gullies are also included in the model, although the coupling between the surface runoff and the sewer network is not considered. Experimental validation of the model is presented in several simplified laboratory configurations of urban catchments, in which the surface runoff has been measured for different hyetographs. The application to a real industrial catchment includes a sewer network flow component, which is solved with the SWMM model. The numerical predictions of the discharge hydrograph generated by a 12 hours storm event are compared with field measurements, providing encouraging results.


Assuntos
Cidades , Indústrias , Modelos Teóricos , Chuva , Movimentos da Água , Engenharia Sanitária
12.
Rev Gastroenterol Mex ; 75(1): 36-41, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-20423781

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is recognized as the most frequent functional digestive disorder around the world. In Latin America and Mexico there are few studies in order to demonstrate its real prevalence in general population. AIMS: To determine the prevalence of IBS in general population from Veracruz City Mexico, using the Rome II criteria. MATERIAL AND METHODS: Using basic information given by bureau for planning urban services from Veracruz country, a 10% random population sample was obtained. Subjects between 16-80 years old were interviewed using a questionnaire based on Rome II criteria and a visual analogous scale in order to estimate the negative effect of IBS symptoms on daily activities. RESULTS: We interviewed 459 subjects with a median age of 31.2 +/- 13.6 years old detecting 78 subjects (16.9%) with IBS symptoms: 25 males and 53 females (gender prevalence of 11.3% and 22.1%, respectively). 28.2% of them had IBS with diarrhea, 50% had IBS with constipation and 21.8% alternating bowel movements, diarrhea and constipation. Negative effect of IBS symptoms on daily activities was significant. CONCLUSIONS: The prevalence of IBS in open population was 16.9% according to Rome II criteria, being higher in those older than 35 years old. Constipation was the predominant pattern. Further studies should evaluate associated factors of these findings.


Assuntos
Síndrome do Intestino Irritável/epidemiologia , Adulto , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , México/epidemiologia , Prevalência , Estudos Retrospectivos , Saúde da População Urbana
13.
Hum Gene Ther ; 17(2): 245-50, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16454658

RESUMO

Fanconi anemia (FA) is an inherited DNA repair disorder characterized by genetic instability of cells lacking a functional FA/BRCA pathway. Previous studies have shown that in vitro stimulation of bone marrow cells (BMCs) from FA mice promotes apoptosis, reduces the reconstitution ability of the stem cells, and induces myelodysplasia and myeloid leukemia upon reinfusion of the cells. This suggests the convenience of adapting standard protocols of gene therapy to FA. Here we show that the reserve of BM progenitors in FA patients is generally below 20% of normal values. Because this reduced reserve could activate the cycling of BM progenitors, we developed a simplified protocol to transduce BMCs from FA patients with gammaretroviral vectors. We demonstrate that a short in vitro manipulation (12-24 hr) of fresh mononuclear BMCs is sufficient to transduce 42% of hematopoietic progenitors from FA-A patients, in the absence of in vitro prestimulation. When FANCA-expressing vectors were used, this simple procedure reversed the phenotype of the BM progenitors from these patients. We propose that our approach will be more efficient and safer compared with standard gene therapy protocols for FA.


Assuntos
Anemia de Fanconi/terapia , Terapia Genética/métodos , Células-Tronco Hematopoéticas/fisiologia , Transdução Genética/métodos , Células da Medula Óssea/fisiologia , Células Cultivadas , Anemia de Fanconi/sangue , Gammaretrovirus/genética , Terapia Genética/efeitos adversos , Humanos , Valores de Referência
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