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2.
Gerodontology ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515010

RESUMO

OBJECTIVES: To assess the effectiveness of amitriptyline (AMT), and to identify the determinants of the treatment's effectiveness in patients diagnosed with burning mouth syndrome (BMS). BACKGROUND: Treatment of BMS is challenging and no established treatment protocol is available. AMT may be an important treatment option, cout not all patients benefit from this drug. Studies assessing factors related to treatment response are valuable in improving decision-making. MATERIALS AND METHODS: This case series study examined the medical records of all patients diagnosed with BMS at an oral medicine unit in a university hospital from 2008 to 2022. The patients were divided into responders to AMT and non-responders to AMT. Data on demographic information, comorbidities, medications, types of symptoms and oral subsites affected were collected. Descriptive and bivariate analyses were conducted to assess the association between the independent variables and the outcome, using the Chi-squared test (P < .05). RESULTS: Three hundred and fourty-nine patients reported a burning mouth sensation, 50 of them (14.3%) being diagnosed with primary BMS. Of these, 35 were treated with AMT, and 26 (74.2%) responded significantly to AMT. All males responded to AMT, whereas only 67.9% of females responded. The mean dose of AMT among responders was 29.8 ± 12.3 mg, with most patients achieving a response with 25 mg (61.5% of patients), followed by 50 mg (23%). The concomitant use of an anticonvulsant resulted in non-response. CONCLUSIONS: AMT may be effective in BMS management for most patients.

3.
Pathol Res Pract ; 242: 154301, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36610326

RESUMO

GRP78 is a chaperone with anti-apoptotic function associated with aggressive tumors. This systematic review aimed to evaluate GRP78 expression in cancer and its relation to prognosis outcomes. This review was conducted in different databases searching for human cancer studies assessing GRP78 immunohistochemical levels on tissue samples. A total of 98 manuscripts were included. In 62% of the studies, GRP78 was associated with a worse prognosis. A meta-analysis included 29 studies that detected a significantly higher expression of GRP78 in cancer tissues (RR= 2.35, 95% CI 1.75-3.15) compared to control. A meta-analysis of 3 and 5-years Overall Survival revealed an increased risk of death for tumors with high expression of GRP78 (RR=1.36, 95%CI 1.16-1,59, I2 = 57%) and (RR=1.65, 95%CI 1.22-2.21, I2 =64%), respectively. GRP78 is an important prognostic biomarker for different types of cancer and a promising therapeutic target.


Assuntos
Chaperona BiP do Retículo Endoplasmático , Neoplasias , Humanos , Proteínas de Choque Térmico/metabolismo , Prognóstico , Biomarcadores , Glucose
4.
Artigo em Inglês | LILACS | ID: biblio-1511467

RESUMO

Introduction: The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is one of the most widely used pesticides in the world. There is evidence that this herbicide can induce deleterious effects in non-target organisms, including impairment of reproduction function. Objective: The aim of this study was to evaluate the reproductive effects of the chronic consumption of contaminated feed with 2,4-D in rats using food environmental spraying simulation. Methods: Animals orally exposed received nebulized chow with 2,4-D solution in different concentrations for 180 days: 0 (control - CG), 20.69 (LCG), 34.63 (MCG), or 51.66 ppm day−1 (HCG). Results: Sperm quality was impaired to 2,4-D. The percentage of sperm with progressive movement, number of sperm in the testis and daily sperm production were decreased in all exposed groups to the herbicide compared to CG. Sperm counts in the caput/corpus and cauda epididymis were reduced in MCG and HCG, and sperm transit time was delayed in the epididymis of LCG. There was a negative impact on sperm morphology and plasma membrane integrity in MCG and HCG, respectively. Germ cell exfoliation within the lumen of the seminiferous tubules and epithelial vacuolization in epididymis were found in the HCG. Conclusion: This is the first study to describe the negative impact on male reproductive morphophysiology after chronic exposure to 2,4-D using food nebulization in environmentally relevant concentrations, based on agronomic use of the herbicide. The reproductive injuries identified raise concerns about the impacts of wide population exposure to 2,4-D (AU).


Introdução: O herbicida 2,4- ácido diclorofenoxiacético (2,4-D) é um dos agrotóxicos mais utilizados no mundo. Há evidências de que este herbicida pode induzir efeitos deletérios em organismos não-alvo, incluindo prejuízo na função reprodutiva. Objetivo: O objetivo deste estudo foi avaliar os efeitos reprodutivos do consumo crônico de ração contaminada com 2,4-D em ratos, utilizando simulação de pulverização ambiental de alimentos. Métodos: Animais expostos oralmente receberam ração nebulizada com solução de 2,4-D em diferentes concentrações por 180 dias: 0 (controle - GC), 20,69 (LCG), 34,63 (MCG) ou 51,66 ppm dia−1 (HCG). Resultados: A qualidade espermática foi prejudicada pelo 2,4-D. A porcentagem de espermatozoides com movimento progressivo, número de espermatozoides no testículo e produção diária de espermatozoides foram menores em todos os grupos expostos ao herbicida, quando comparados ao GC. A contagem de espermatozoides na cabeça/corpo e cauda do epidídimo foi reduzida em MCG e HCG, e o tempo de trânsito espermático atrasou no epidídimo em LCG. Houve impacto negativo na morfologia espermática e na integridade da membrana plasmática em MCG e HCG, respectivamente. Esfoliação de células germinativas no lúmen dos túbulos seminíferos e vacuolização epitelial no epidídimo foram encontradas em HCG. Conclusão: Este é o primeiro estudo a descrever o impacto negativo na morfofisiologia reprodutiva masculina após exposição crônica ao 2,4-D, utilizando nebulização de alimentos em concentrações ambientalmente relevantes, com base no uso agronômico do herbicida. As lesões reprodutivas identificadas levantam preocupações sobre os impactos da ampla exposição da população ao 2,4-D (AU).


Assuntos
Animais , Ratos , Reprodução , Espermatozoides , Agroquímicos/toxicidade , Exposição a Praguicidas , Exposição Ambiental
5.
Molecules ; 27(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36234863

RESUMO

Poly(p-anisidine) (PPA) is a polyaniline derivative presenting a methoxy (-OCH3) group at the para position of the phenyl ring. Considering the important role of conjugated polymers in novel technological applications, a systematic, combined experimental and theoretical investigation was performed to obtain more insight into the crystallization process of PPA. Conventional oxidative polymerization of p-anisidine monomer was based on a central composite rotational design (CCRD). The effects of the concentration of the monomer, ammonium persulfate (APS), and HCl on the percentage of crystallinity were considered. Several experimental techniques such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), multifractal analysis, Nuclear Magnetic Resonance (13C NMR), Fourier-transform Infrared spectroscopy (FTIR), and complex impedance spectroscopy analysis, in addition to Density Functional Theory (DFT), were employed to perform a systematic investigation of PPA. The experimental treatments resulted in different crystal structures with a percentage of crystallinity ranging from (29.2 ± 0.6)% (PPA1HT) to (55.1 ± 0.2)% (PPA16HT-HH). A broad halo in the PPA16HT-HH pattern from 2θ = 10.0-30.0° suggested a reduced crystallinity. Needle and globular-particle morphologies were observed in both samples; the needle morphology might have been related to the crystalline contribution. A multifractal analysis showed that the PPA surface became more complex when the crystallinity was reduced. The proposed molecular structures of PPA were supported by the high-resolution 13C NMR results, allowing us to access the percentage of head-to-tail (HT) and head-to-head (HH) molecular structures. When comparing the calculated and experimental FTIR spectra, the most pronounced changes were observed in ν(C-H), ν(N-H), ν(C-O), and ν(C-N-C) due to the influence of counterions on the polymer backbone as well as the different mechanisms of polymerization. Finally, a significant difference in the electrical conductivity was observed in the range of 1.00 × 10-9 S.cm-1 and 3.90 × 10-14 S.cm-1, respectively, for PPA1HT and PPA16HT-HH.


Assuntos
Polímeros , Compostos de Anilina , Cristalização/métodos , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Molecules ; 27(12)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35744819

RESUMO

Poly(o-methoxyaniline) emeraldine-salt form (ES-POMA) was chemically synthesized using hydrochloric acid and subjected to a heat treatment (HT) process for 1 h at 100 °C (TT100) and 200 °C (TT200). The HT process promoted a progressive decrease in crystallinity. The Le Bail method revealed a decomposition from tetrameric to trimeric-folded chains after the HT process. The unheated POMA-ES presented a globular vesicular morphology with varied micrometric sizes. The heat treatment promoted a reduction in these globular structures, increasing the non-crystalline phase. The boundary length (S) and connectivity/Euler feature (χ) parameters were calculated from the SEM images, revealing that ES-POMA presented a wide distribution of heights. The TT100 and TT200 presented a narrow boundary distribution, suggesting smoother surfaces with smaller height variations. The UV-VIS analysis revealed that the transition at 343 nm (nonlocal π → π*) was more intense in the TT200 due to the electronic delocalization, which resulted from the reduced polymer chain caused by the HT process. In addition to the loss of conjugation, counter ion withdrawal reduced the ion-chain interaction, decreasing the local electron density. This result shows the influence of the chlorine counter ions on the peaks position related to the HOMO → LUMO transition, since the π → polaron transition occurs due to the creation of the energy states due to the presence of counter ions. Finally, the electrical conductivity decreased after the HT process from 1.4 × 10-4 S.cm-1 to 2.4 × 10-6 S.cm-1 as result of the polymer deprotonation/degradation. Thus, this paper proposed a systematic evaluation of the POMA molecular structure and crystallite size and shape after heat treatment.


Assuntos
Temperatura Alta , Poliaminas , Compostos de Anilina , Condutividade Elétrica , Poli A , Poliaminas/química , Polímeros/química
7.
Acta Trop ; 230: 106395, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35278367

RESUMO

Piperine is an alkaloid extracted from the seed of Piper spp., which has demonstrated a larvicidal effect against Ae. aegypti. The incorporation of piperine into nanostructured systems can increase the effectiveness of this natural product in the control of Ae. aegypti larvae. In this study, we evaluated the effectiveness of piperine loaded or not into two nanostructured systems (named NS-A and NS-B) prepared by the nanoprecipitation method. The Ae. aegypti larvae were exposed to different concentrations of piperine loaded or not (2 to 16 ppm) and the mortality was investigated after 24, 48, and 72 hours. The nanostructures prepared were spherical in shape with narrow size distribution and great encapsulation efficiency. The lethal concentration 50 (LC50) for non-loaded piperine were 13.015 ppm (24 hours), 8.098 ppm (48 hours), and 7.248 ppm (72 hours). The LC50 values found for NS-A were 35.378 ppm (24 hours), 12.091 ppm (48 hours), and 8.011 ppm (72 hours), whereas the values found for NS-B were 21.267 ppm (24 hours), 12.091 ppm (48 hours), and 8.011 ppm (72 hours). Collectively, these findings suggested that non-loaded piperine caused higher larval mortality in the first hours of exposure while the nanostructured systems promoted the slow release of piperine and thereby increased the larvicidal activity over time. Therefore, loading piperine into nanostructured systems might be an effective tool to improve the larval control of vector Ae. aegypti.


Assuntos
Aedes , Alcaloides , Inseticidas , Nanoestruturas , Alcaloides/farmacologia , Animais , Benzodioxóis , Inseticidas/farmacologia , Larva , Mosquitos Vetores , Piperidinas , Extratos Vegetais/química , Polímeros , Alcamidas Poli-Insaturadas
8.
Life Sci ; 288: 120163, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34822797

RESUMO

AIMS: To investigate the role of tumor acidification in cell behavior, migration, and treatment resistance of oral squamous cell carcinoma (OSCC). MAIN METHODS: The SCC4 and SCC25 cell lines were exposed to acidified (pH 6.8) cell culture medium for 7 days. Alternatively, a long-term acidosis was induced for 21 days. In addition, to mimic dynamic pH fluctuation of the tumor microenvironment, cells were reconditioned to neutral pH after experimental acidosis. This study assessed cell proliferation and viability by sulforhodamine B and flow cytometry. Individual and collective cell migration was analyzed by wound healing, time lapse, and transwell assays. Modifications of cell phenotype, EMT induction and stemness potential were investigated by qRT-PCR, western blot, and immunofluorescence. Finally, resistance to chemo- and radiotherapy of OSCC when exposed to acidified environmental conditions (pH 6.8) was determined. KEY FINDINGS: The exposure to an acidic microenvironment caused an initial reduction of OSCC cells viability, followed by an adaptation process. Acidic adapted cells acquired a mesenchymal-like phenotype along with increased migration and motility indexes. Moreover, tumoral extracellular acidity was capable to induce cellular stemness and to increase chemo- and radioresistance of oral cancer cells. SIGNIFICANCE: In summary, the results showed that the acidic microenvironment leads to a more aggressive and treatment resistant OSCC cell population.


Assuntos
Ácidos/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Neoplasias Bucais/patologia , Células-Tronco Neoplásicas/patologia , Tolerância a Radiação , Microambiente Tumoral , Antineoplásicos/farmacologia , Apoptose , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Movimento Celular , Proliferação de Células , Cisplatino/efeitos adversos , Raios gama/efeitos adversos , Humanos , Neoplasias Bucais/etiologia , Neoplasias Bucais/terapia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos da radiação , Células Tumorais Cultivadas
9.
J Phys Chem A ; 125(40): 8791-8802, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34605656

RESUMO

Methanesulfonic acid (CH3SO3H), also known as MSA, has been found to be capable of forming a strong hydrogen-bonded interaction with sulfuric acid (H2SO4) under ambient conditions. The energetic stability of the MSA···H2SO4 clusters increases with decreasing temperature at higher altitudes in the troposphere, which is relevant in the context of atmospheric aerosol formation. We have performed, in the present work, a detailed and systematic quantum-chemical calculation with high-level density functional theory to characterize the hydrogen bond formation in the binary MSA···H2SO4, ternary MSA···(H2SO4)2, and quaternary MSA···(H2SO4)3 clusters. The five different conformations of MSA···(H2SO4)2 and six conformations of MSA···(H2SO4)3, considered in the present work for the spectroscopic analysis, have been taken from our previous work [J. Phys. Chem. A. 2020, 124, 11072-11085]. The hydrogen bonds were analyzed on the basis of infrared vibrational frequencies of different O-H stretching modes and quantum theory of atoms in molecules (QTAIM). A strong positive correlation has been observed between the red shift of the OH groups in MSA and H2SO4 and the corresponding O-H elongation as a result of hydrogen bond formation. Topological analysis employing QTAIM shows that most of the charge density and the Laplacian values at bond critical points (BCPs) of the hydrogen bonds of the MSA···(H2SO4)n (n = 1-3) complexes fall within the standard hydrogen-bond criteria. However, those outside these criteria fall in the category of a very strong hydrogen bond with a hydrogen bond length as low as 1.41 Å and an O-H bond elongation as high as 0.096 Å. In general, the charge densities of the BCPs located on hydrogen bonds increase as the hydrogen-bond lengths decrease. Proportionately, a larger number of hydrogen bonds in ternary MSA···(H2SO4)2 demonstrate a partial covalent character when compared with the quaternary clusters.

10.
J Phys Chem A ; 124(52): 11072-11085, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33337158

RESUMO

A detailed and systematic quantum-chemical calculation has been performed with high-level density functional theory (DFT) to analyze the electrostatic interaction of methanesulfonic acid (CH3SO3H), also known as MSA, with pre-formed clusters of sulfuric acid (H2SO4) molecules in ambient conditions. Both MSA and H2SO4 are considered as atmospheric molecules that might play active roles in aerosol formation. The interactions between MSA and H2SO4 clusters lead to the formation of MSA···(H2SO4)n (n = 2, 3) complexes stabilized by the formation of different types of intermolecular hydrogen bond networks. Analyses of cluster binding energies and free energy changes associated with their formation indicate that MSA could bring additional stability into the atmospheric molecular clusters responsible for aerosol formation. Variations of Gibbs free energy with temperature and pressure have been analyzed. The lower temperatures and pressures at the higher altitudes of the troposphere are found to play in favor of higher stability of the MSA···(H2SO4)n clusters. Effects of hydrogen bond formation on dipole moment, mean polarizability, and anisotropy of polarizability of the clusters have been analyzed. Rayleigh scattering intensities are found to increase many-fold when light interacts with the MSA···(H2SO4)n clusters.

11.
Biosci. j. (Online) ; 31(2): 392-403, mar./abr. 2015.
Artigo em Português | LILACS | ID: biblio-963916

RESUMO

Objetivou-se no presente trabalho ajustar diversos modelos matemáticos ao processo de secagem dos frutos de Crambe abyssinica, em diversas condições de ar, bem como determinar o coeficiente de difusão efetivo e obter a energia de ativação. O trabalho foi realizado no Laboratório de Pós-colheita de Produtos Vegetais do Instituto Federal de Educação, Ciência e Tecnologia Goiano ­ Câmpus Rio Verde, Goiás, Brasil (IF Goiano ­ Câmpus Rio Verde). A colheita do crambe (Crambe abyssinica Hochst) da cultivar FMS Brilhante foi realizada manualmente, com o teor de água de 38,0±1,0 (% b.s.) e secados até o teor de 8,0±1,5 (% b.s.). A secagem foi realizada sob diferentes condições controladas de temperatura 35, 45, 60, 75 e 90 °C e umidades relativas de 20,9; 8,7; 6,8; 4,8 e 2,3%, respectivamente. Dentre os modelos analisados, Page foi o melhor que se ajustou aos dados nas diferentes condições do ar de secagem. O coeficiente de difusão efetivo aumentou com a elevação da temperatura apresentando valores de 2,84 x 10-11; 3,22 x 10-11; 5,00 x 10-11; 7,27 x 10-11 e 9,14 x 10-11 m2 s-1, para as temperaturas de 35, 45, 60, 75 e 90 °C, respectivamente, durante a secagem dos frutos de crambe. A relação entre o coeficiente de difusão efetivo e a temperatura de secagem pode ser descrita pela equação de Arrhenius, que apresenta uma energia de ativação para a difusão líquida na secagem de 20,998 kJ mol-1.


The arm in this work was set several mathematical models to the process of drying the fruits of Crambe abyssinica in different air conditions and to determine the effective diffusion coefficient and obtain the activation energy. The work was performed at the Laboratory of Postharvest Products Vegetables of Instituto Federal de Educação, Ciência e Tecnologia Goiano ­ Câmpus Rio Verde, Goiás, Brasil (IF Goiano - Câmpus Rio Verde). The harvest of crambe (Crambe abyssinica Hochst) cultivar FMS Brilhante was performed manually with a water content of 38.0±1.0 (% d.b.) and dried until the content of 8.0±1.5 (d.b.% ). The drying procedure was conducted under different temperature controlled conditions of 35, 45, 60, 75 and 90 °C and relative humidity of 20.9, 8.7, 6.8, 4.8 and 2.3% respectively. Among the models that presented the best fit to the experimental data, Page was the best fit for the data in the different conditions of the drying air. The effective diffusion coefficient increased with increasing temperature with values of 2.84 x 10-11, 3.22 x 10-11, 5.00 x 10-11, 7.27 x 10-11 and 9.14 x 10-11 m2 s-1, at temperatures of 35, 45, 60, 75 and 90 °C, respectively, during the drying of crambe fruits. The relation between the effective diffusion coefficient and the drying temperature may be described by the Arrhenius equation, which has an activation energy for the liquid diffusion in drying of 20.998 kJ mol-1.


Assuntos
Cromatografia em Camada Delgada , Crambe (Planta) , Modelos Teóricos
12.
Rev. bras. cir. cardiovasc ; 6(2): 128-31, maio-ago. 1991. ilus
Artigo em Português | LILACS | ID: lil-164330

RESUMO

Paciente adulta, portadora de anomalia vascular congênita do arco aórtico com formaçao de anel envolvendo traquéia e esôfago, com compressao deste e conseqüente disfagia progressiva. A abordagem cirúrgica foi realizada por toracotomia lateral direita, com ressecçao do divertrículo de Kommerell, secçao do ligamento arterioso e ligadura simples da artéria subclávia, com regressao total dos sintomas. Nao foi observada síndrome de roubo da subclávia ou isquemia do membro superior esquerdo. Os autores discutem o tipo de abordagem e cirurgia para tratamento desta rara anomalia.


Assuntos
Adulto , Feminino , Humanos , Aorta Torácica/anormalidades , Doenças do Esôfago/etiologia , Aorta Torácica/cirurgia , Ecocardiografia
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