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1.
Waste Manag ; 181: 176-187, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38614039

RESUMO

This study presented the influence of two types of clay: kaolin (Kao) and red clay (RC) on the chemical and physical properties of ceramic specimens when galvanic sludge (GS) is incorporated to encapsulate heavy metals. Samples were obtained of GS from the industrial district of Manaus - Amazonas State, Brazil, and kaolin (Kao), and red clay (RC) from the Central Amazon. A fourth sample was prepared by mixing GS, Kao, and RC in the ratio 1:1:8 (GS + Kao + RC). This mixture was ground, and ceramic specimens were prepared, and heat treated at 950 °C and 1200 °C for three hours for phase detection, compressive strength, leaching of Fe, Ni and Cr metals and life cycle assessment. Galvanic sludge, Kao, and RC were also, and heat treated to at 950 °C and 1200 °C for three hours, obtaining GS950, GS1200, Kao950, Kao1200, RC950, and RC1200. The samples were submitted to XRF, XRD, Rietveld refinement, Mössbauer spectroscopy, TG/DTG/DSC, and SEM. The results show that the formation of nickel oxide and a spinel solid solution of the type Fe3+{Fe1-y3+,Fe1-x2+,Nix2+,Cry3+}O4 (in which [] = tetrahedral site, {} octahedral site) occurs in GS1200, which is caused by sulfate decomposition to SO2. At 1200 °C, heavy metals are encapsulated, forming other phases such as nickel silicate and hematite. Life cycle assessment was used to verify the sustainability and value of GS in clay for making bricks, and it indicated that the production of ceramics is feasible, reduces the use of clays, and is sustainable.


Assuntos
Cerâmica , Argila , Caulim , Metais Pesados , Esgotos , Caulim/química , Argila/química , Metais Pesados/química , Metais Pesados/análise , Cerâmica/química , Esgotos/química , Brasil
2.
Braz J Biol ; 83: e275698, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37937631

RESUMO

The pandemic and the geopolitical conflict between Russia and Ukraine are events that have caused economic instability in Peru. Reason that was investigated on the analysis of the biological and chemical characteristics of cabbage fed with compost based on sugarcane residues. The objective was to analyze the physical, chemical and biological characteristics of cabbage from the adequate dose of compost based on sugarcane residues and distance between plants. It is based on the methodology applied with an experimental approach, for which the Completely Random Block Design with a 4x 2 factorial arrangement was used, which consisted of 3 blocks and 8 treatments that were the combination: F1 with 0, F2 with 8, T3 with 10 and F4 with 12 t/ha and spacing (D1) with 0.30 m between plants and 0.60 m between rows and (D2) with 0.35 m between plants and 0.60 m between rows. The physical characteristics of cabbage were evaluated and processed by analysis of variance, nutrient concentrations in leaves and stomatal density were analyzed. The results determined that T7 stood out in plant height with 41.88 cm, yield with 26.76 tn/ha and T6 in root length with 20.22 cm. In chemical analysis of leaves T1 stood out in nitrogen, phosphorus, potassium and T4 in calcium, magnesium and sulfur. In T7 stomata density with 977 stomata/mm2. It concludes that at an adequate dose and greater distance that T7 stands out in the concentration of nutrients that are within normal values and high density of stomata; Therefore, these characteristics influenced the optimal biochemical reactions, which obtained good development and yield that differed at 51.39% and 32.17% with respect to the controls T1 and T5.


Assuntos
Brassica , Compostagem , Saccharum , Brassica/química , Federação Russa
3.
Inorg Chem ; 62(10): 4291-4303, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36862825

RESUMO

In this work, we focus on understanding the morphology and photocatalytic properties of CeO2 nanocrystals (NCs) synthesized via a microwave-assisted solvothermal method using acetone and ethanol as solvents. Wulff constructions reveal a complete map of available morphologies and a theoretical-experimental match with octahedral nanoparticles obtained through synthesis using ethanol as solvent. NCs synthesized in acetone show a greater contribution of emission peaks in the blue region (∼450 nm), which may be associated with higher Ce3+ concentration, originating shallow-level defects within the CeO2 lattice while for the samples synthesized in ethanol a strong orange-red emission (∼595 nm) suggests that oxygen vacancies may originate from deep-level defects within the optical bandgap region. The superior photocatalytic response of CeO2 synthesized in acetone compared to that of CeO2 synthesized in ethanol may be associated with an increase in long-/short-range disorder within the CeO2 structure, causing the Egap value to decrease, facilitating light absorption. Furthermore, surface (100) stabilization in samples synthesized in ethanol may be related to low photocatalytic activity. Photocatalytic degradation was facilitated by the generation of ·OH and ·O2- radicals as corroborated by the trapping experiment. The mechanism of enhanced photocatalytic activity has been proposed suggesting that samples synthesized in acetone tend to have lower e'─h· pair recombination, which is reflected in their higher photocatalytic response.

4.
Neurologia (Engl Ed) ; 2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35882307

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is characterised by recurrent attacks of optic neuritis and transverse myelitis. The purpose of this work was to identify the incidence and prevalence of NMOSD and its clinical characteristics in the population treated for demyelinating diseases in Western Mexico. MATERIAL AND METHOD: A descriptive, retrospective study was carried out in the Department of Neurology, at the Sub-specialty Medical Unit, Specialties Hospital (known by its Spanish abbreviation UMAE-HE), of the National Western Medical Center (CMNO), Mexican Institute of Social Security (IMSS). A review of the electronic files for all patients with a diagnosis of NMOSD in 2019, was carried out in the State of Jalisco, Mexico. RESULTS: Fifty-eight patients with NMOSD were included in the study. The incidence was 0.71/100 000 (CI 0.60-0.85) and the prevalence was 1.09/100 000 (CI 0.84-1.42). There were 79.3% women, and 20.6% were men (P = .01). All (100%) patients presented with anti-aquaporin-4 immunoglobulin G, and 89.6% showed seropositivity for anti-aquaporin-4 (CI 82.6-94.9). Magnetic resonance imaging was performed on 100% of patients, where 34.4% were normal, and 65.5% (38) abnormal, presenting with non-specific subcortical lesions (P = 0.04). The initial clinical presentation was optic neuritis (ON) in 58.6%; where 31.0% was bilateral ON, 20.7% was left ON, and 6.9% were right ON; transverse myelitis in 26.0%, area postrema syndrome (APS) in 10.3%, among others. CONCLUSIONS: The incidence of NMOSD exceeds 0.71/100 000, the prevalence is low at 1.09/100 000, and NMOSD is predominantly found in women.

5.
Rev Gastroenterol Mex (Engl Ed) ; 87(1): 13-19, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35090672

RESUMO

INTRODUCTION AND AIMS: Endoscopic submucosal dissection (ESD) is a well-established treatment for superficial gastrointestinal tumors and enables en bloc resection. Adequate tissue tension is important for safe and effective dissection. Simplified magnetic anchor-guided ESD (MAG-ESD) with a neodymium magnet has potential benefits, compared with other current traction methods. We evaluated the feasibility of simplified MAG-ESD in an ex vivo porcine model. MATERIALS AND METHODS: An experimental study was conducted, utilizing the standard ESD technique. An external magnet and an internal magnet, both neodymium magnets, were used for the magnetic anchoring. The internal magnet was attached to an arm of a hemoclip with a 2-0 silk suture. After the incision, the clip with the internal magnet was placed at the edge of the lesion. The external magnet was maneuvered around the surface to apply adequate tension. RESULTS: A total of 15 en bloc ESDs (5 with no magnetic anchoring and 10 with magnetic anchoring) were carried out. Traction and dissection were feasible in all cases and the procedures were completed in fewer than 90min. Lesion size ranged from 15 to 50mm (mean 30mm). Two cases in the group with magnetic anchoring presented with punctate perforation (13.3%). CONCLUSIONS: Our study demonstrated the feasibility of simplified MAG-ESD and en bloc resection in an ex vivo porcine model.


Assuntos
Ressecção Endoscópica de Mucosa , Animais , Dissecação , Humanos , Fenômenos Magnéticos , Imãs , Neodímio , Suínos
6.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33516586

RESUMO

INTRODUCTION AND AIMS: Endoscopic submucosal dissection (ESD) is a well-established treatment for superficial gastrointestinal tumors and enables en bloc resection. Adequate tissue tension is important for safe and effective dissection. Simplified magnetic anchor-guided ESD (MAG-ESD) with a neodymium magnet has potential benefits, compared with other current traction methods. We evaluated the feasibility of simplified MAG-ESD in an ex vivo porcine model. MATERIALS AND METHODS: An experimental study was conducted, utilizing the standard ESD technique. An external magnet and an internal magnet, both neodymium magnets, were used for the magnetic anchoring. The internal magnet was attached to an arm of a hemoclip with a 2-0 silk suture. After the incision, the clip with the internal magnet was placed at the edge of the lesion. The external magnet was maneuvered around the surface to apply adequate tension. RESULTS: A total of 15 en bloc ESDs (five with no magnetic anchoring and 10 with magnetic anchoring) were carried out. Traction and dissection were feasible in all cases and the procedures were completed in fewer than 90 min. Lesion size ranged from 15 to 50 mm (mean 30 mm). Two cases in the group with magnetic anchoring presented with punctate perforation (13.3%). CONCLUSIONS: Our study demonstrated the feasibility of simplified MAG-ESD and en bloc resection in an ex vivo porcine model.

8.
Life Sci ; 216: 22-28, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30414975

RESUMO

AIMS: Pregnancy is a physiological stage with profound cardiovascular changes leading to hypotension. Preeclampsia (PE) reverts these normal changes inducing hypertension. Renin-angiotensin system (RAS) has been related in PE genesis. It has been reported a novel receptor in the system, the Prorenin/Renin receptor (PRR), with several roles in renal and cardiovascular illnesses. It is not known, however, if PRR changes its expression or is activated during normal or PE-complicated pregnancy on tissues intimately related to hypertension. So, the aim of this work was to describe PRR expression during normal and hypertensive pregnancy in rats. METHODS: We used a subrenal aortic coarctation (SRAC) model in rats. Atria, septum and ventricular heart tissue, aorta and renal tissue samples were homogenized and immunoblotted using anti-PRR and anti-PLZF antibodies. We also measured gene expression by RT-PCR. KEY FINDINGS: Hypertension and proteinuria were observed in SRAC-pregnant rats. In pregnant, non-SRAC rats, PRR showed a higher expression of both, gene and protein compared to non-pregnant rats in heart, aorta and kidney tissues. PE induces a very high expression of PRR in cardiac tissues and, on the contrary, decreases PRR expression in both, aorta and kidney. PLZF, a marker of PRR function, was augmented only in aorta and kidney in non-SRAC pregnant rats. In SRAC-pregnant rats, PLZF increment disappeared. SIGNIFICANCE: These findings indicate that PRR expression changes differently during pregnancy and PE in tissues related to cardiovascular functions and suggest a probable participation of the receptor during normal and preeclamptic pregnancy in the rat.


Assuntos
Hipertensão Induzida pela Gravidez/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Proteinúria/fisiopatologia , Receptores de Superfície Celular/genética , Sistema Renina-Angiotensina , Animais , Aorta/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Hipertensão Induzida pela Gravidez/genética , Rim/metabolismo , Pré-Eclâmpsia/genética , Gravidez , Ratos , Ratos Wistar , Receptores de Superfície Celular/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , ATPases Vacuolares Próton-Translocadoras
9.
J Neuroimmunol ; 320: 117-124, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29661540

RESUMO

Macrophage migration inhibitory factor (MIF) is a cytokine associated with tissue damage in multiple autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis and psoriatic arthritis. The role of MIF in multiple sclerosis (MS) and the contribution of its polymorphisms are unknown in our population. Therefore, we decided to investigate the genetic association of -794 CATT5-8 (rs5844572) and -173 G>C (rs755622) MIF polymorphisms with MS, clinical variables and MIF serum levels in the population of western Mexico. 230 MS patients diagnosed according to McDonald criteria and 248 control subjects (CS) were recruited for this study, both polymorphisms were genotyped by PCR and PCR-RFLP and MIF serum levels were measured by ELISA kit. Severity and progression of MS were evaluated by EDSS and MSSS scores, respectively. Genotypes carrying the 5 repeats alleles of -794 CATT5-8MIF polymorphism present higher MIF serum levels in comparison with no carriers, and the presence of 5,7 heterozygous genotype contribute to the increase of disease severity and damage progression in MS patients. Notably when we stratified by sex, an effect of risk alleles (7 repeats and -173*C) of both MIF polymorphisms on EDSS and MSSS scores on males was found (p < 0.01). This study suggests that polymorphic alleles of MIF polymorphisms could act as sex-specific disease modifiers that increase the severity and progression of MS in male Mexican-Mestizo western population.


Assuntos
Predisposição Genética para Doença/genética , Oxirredutases Intramoleculares/genética , Fatores Inibidores da Migração de Macrófagos/genética , Esclerose Múltipla/genética , Caracteres Sexuais , Adulto , Progressão da Doença , Feminino , Genótipo , Humanos , Masculino , México , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
10.
Gac Med Mex ; 153(Supl. 2): S72-S81, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-29099102

RESUMO

Objective: To determine the effect of melatonin (MEL) administration on ciclooxigenase 2 (COX-2) activity and serum concentration of nitric oxide metabolites, lipoperoxides and glutathione peroxidase (GPx) activity in patients with Parkinson's disease. Methods: Prospective double-blind randomized clinical pilot trial. 13 patients were included and two groups were formed: MEL at doses of 25 mg orally every 12 hours for 12 months and placebo with corn starch. Patients were assessed using the Unified Parkinson's Disease Scale. A blood sample was taken at baseline and every 3 months until 12 months. Results: COX-2 activity decreased as did nitrates/nitrites (3, 6 and 9 months) and lipoperoxides (9 and 12 months); GPx exhibited no significant differences.


Assuntos
Antioxidantes/farmacologia , Ciclo-Oxigenase 2/metabolismo , Glutationa Peroxidase/sangue , Peróxidos Lipídicos/sangue , Melatonina/farmacologia , Óxido Nítrico/metabolismo , Doença de Parkinson/metabolismo , Antioxidantes/administração & dosagem , Método Duplo-Cego , Humanos , Melatonina/administração & dosagem , Estresse Oxidativo , Projetos Piloto , Estudos Prospectivos
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