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1.
Neurosci Lett ; 808: 137292, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37156440

RESUMO

Caffeic acid is a polyphenolic compound present in a vast array of dietary components. We previously showed that caffeic acid reduces the burden of brain ischemia joining evidence by others that it can attenuate different brain diseases. However, it is unknown if caffeic acid affects information processing in neuronal networks. Thus, we now used electrophysiological recordings in mouse hippocampal slices to test if caffeic acid directly affected synaptic transmission, plasticity and dysfunction caused by oxygen-glucose deprivation (OGD), an in vitro ischemia model. Caffeic acid (1-10 µM) was devoid of effect on synaptic transmission and paired-pulse facilitation in Schaffer collaterals-CA1 pyramidal synapses. Also, the magnitude of either hippocampal long-term potentiation (LTP) or the subsequent depotentiation were not significantly modified by 10 µM caffeic acid. However, caffeic acid (10 µM) increased the recovery of synaptic transmission upon re-oxygenation following 7 min of OGD. Furthermore, caffeic acid (10 µM) also recovered plasticity after OGD, as heralded by the increased magnitude of LTP after exposure. These findings show that caffeic acid does not directly affect synaptic transmission and plasticity but can indirectly affect other cellular targets to correct synaptic dysfunction. Unraveling the molecular mechanisms of action of caffeic acid may allow the design of hitherto unrecognized novel neuroprotective strategies.


Assuntos
Hipocampo , Transmissão Sináptica , Camundongos , Animais , Transmissão Sináptica/fisiologia , Potenciação de Longa Duração/fisiologia , Isquemia , Plasticidade Neuronal/fisiologia
2.
Purinergic Signal ; 19(4): 673-683, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36697868

RESUMO

Caffeine is one of the main ergogenic resources used in exercise and sports. Previously, we reported the ergogenic mechanism of caffeine through neuronal A2AR antagonism in the central nervous system [1]. We now demonstrate that the striatum rules the ergogenic effects of caffeine through neuroplasticity changes. Thirty-four Swiss (8-10 weeks, 47 ± 1.5 g) and twenty-four C57BL/6J (8-10 weeks, 23.9 ± 0.4 g) adult male mice were studied behaviorly and electrophysiologically using caffeine and energy metabolism was studied in SH-SY5Y cells. Systemic (15 mg/kg, i.p.) or striatal (bilateral, 15 µg) caffeine was psychostimulant in the open field (p < 0.05) and increased grip efficiency (p < 0.05). Caffeine also shifted long-term depression (LTD) to potentiation (LTP) in striatal slices and increased the mitochondrial mass (p < 0.05) and membrane potential (p < 0.05) in SH-SY5Y dopaminergic cells. Our results demonstrate the role of the striatum in the ergogenic effects of caffeine, with changes in neuroplasticity and mitochondrial metabolism.


Assuntos
Estimulantes do Sistema Nervoso Central , Neuroblastoma , Substâncias para Melhoria do Desempenho , Humanos , Masculino , Camundongos , Animais , Cafeína/farmacologia , Camundongos Endogâmicos C57BL , Estimulantes do Sistema Nervoso Central/farmacologia
3.
J Biochem Mol Toxicol ; 36(5): e23007, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35199402

RESUMO

Metformin is the first-line drug to treat type 2 diabetes mellitus. Its mechanism of action is still debatable, and recent studies report that metformin attenuates oxidative stress. This study evaluated the in vitro antioxidant effects of a broad range of metformin concentrations on insulin-producing cells. The cell cycle, metabolism, glucose-stimulated insulin secretion, and cell death were evaluated to determine the biguanide effects on beta-cell function and survival. Antioxidant potential was based on reactive oxygen species (ROS), reduced glutathione (GSH), oxidative stress biomarker levels, and antioxidant enzyme and transcriptional factor Nrf2 activities. The results demonstrate that metformin disrupted GSIS in a concentration-dependent manner, lowered insulin content, and attenuated beta-cell metabolism. At high concentrations, metformin induced cell death and cell cycle arrest as well as increased ROS generation, consequently reducing GSH content. Although carbonylated protein content was elevated, indicating oxidative stress, the antioxidant enzyme and Nrf2 activities were not altered. In conclusion, our results show that metformin disrupts pancreatic beta-cell functionality but does not exert a putative antioxidant effect. It is important to note that the drug could potentially affect beta-cells, especially at high circulating levels.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Metformina , Animais , Antioxidantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Ratos , Espécies Reativas de Oxigênio/metabolismo
4.
Am J Physiol Regul Integr Comp Physiol ; 320(4): R541-R546, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33533311

RESUMO

Physical exercise attenuates the development of l-3,4-dihydroxyphenylalanine (l-DOPA)-induced dyskinesia (LID) in 6-hydroxydopamine-induced hemiparkinsonian mice through unknown mechanisms. We now tested if exercise normalizes the aberrant corticostriatal neuroplasticity associated with experimental murine models of LID. C57BL/6 mice received two unilateral intrastriatal injections of 6-hydroxydopamine (12 µg) and were treated after 3 wk with l-DOPA/benserazide (25/12.5 mg/kg) for 4 wk, with individualized moderate-intensity running (60%-70% V̇o2peak) or not (untrained). l-DOPA converted the pattern of plasticity in corticostriatal synapses from a long-term depression (LTD) into a long-term potentiation (LTP). Exercise reduced LID severity and decreased aberrant LTP. These results suggest that exercise attenuates abnormal corticostriatal plasticity to decrease LID.


Assuntos
Antiparkinsonianos/toxicidade , Córtex Cerebral/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Discinesia Induzida por Medicamentos/prevenção & controle , Terapia por Exercício , Levodopa/toxicidade , Plasticidade Neuronal/efeitos dos fármacos , Transtornos Parkinsonianos/tratamento farmacológico , Animais , Benserazida/toxicidade , Córtex Cerebral/fisiopatologia , Corpo Estriado/fisiopatologia , Di-Hidroxifenilalanina/análogos & derivados , Modelos Animais de Doenças , Discinesia Induzida por Medicamentos/etiologia , Discinesia Induzida por Medicamentos/fisiopatologia , Potenciação de Longa Duração/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/fisiopatologia , Corrida , Fatores de Tempo
5.
Cell Biochem Funct ; 39(2): 335-343, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32911572

RESUMO

Lixisenatide, a glucagon-like peptide-1 (GLP-1) receptor agonist, is used in the treatment of type 2 diabetes mellitus (T2DM). It increases insulin (INS) secretion and can decrease INS resistance, improving metabolic disorders in this disease. However, its effects on metabolic disturbances in cancer-bearing, which also exhibit decreased INS secretion and INS resistance, changes that may contribute to weight loss (cachexia), have not yet been evaluated. The purpose of this study was to investigate the lixisenatide treatment effects on mild cachexia and related metabolic abnormalities in Walker-256 tumour-bearing rats. Lixisenatide (50 µg kg-1 , SC) was administered once daily, for 6 days, after inoculation of Walker-256 tumour cells. Acute lixisenatide treatment did not improve hypoinsulinemia, INS secretion and INS resistance of tumour-bearing rats. It also did not prevent the reduced glucose and increased triacylglycerol and lactate in the blood and nor the loss of retroperitoneal and epididymal fat of these animals. However, acute lixisenatide treatment accentuated the body mass loss of tumour-bearing rats. Therefore, lixisenatide, unlike T2DM, does not improve hypoinsulinemia and INS resistance associated with cancer, evidencing that it does not have the same beneficial effects in these two diseases. In addition, lixisenatide aggravated weight loss of tumour-bearing rats, suggesting that its use for treatment of T2DM patients with cancer should be avoided. SIGNIFICANCE OF THE STUDY: Lixisenatide increases insulin secretion and appears to reduce insulin resistance in T2DM. However, lixisenatide treatment does not improve hypoinsulinemia and insulin resistance associated with cancer, as it does in T2DM, and aggravated weight loss, suggesting that its use for treatment of T2DM patients with cancer should be avoided.


Assuntos
Hipoglicemiantes/farmacologia , Secreção de Insulina/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Glicemia/análise , Caquexia/prevenção & controle , Linhagem Celular Tumoral , Glucose/farmacologia , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Resistência à Insulina , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Masculino , Peptídeos/uso terapêutico , Ratos , Ratos Wistar , Transplante Heterólogo , Triglicerídeos/sangue , Redução de Peso/efeitos dos fármacos
6.
Polymers (Basel) ; 14(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35012043

RESUMO

With the increase in global demand for biodiesel, first generation feedstock has drawn the attention of governmental institutions due to the correlation with large land farming areas. The second and third feedstock generations are greener feedstock sources, nevertheless, they require different catalytic conditions if compared with first generation feedstock. In this work, we present the synthesis and characterization of oligoesters matrices and their functionalization to act as a pseudo-homogeneous acid catalyst for biodiesel production, named Oligocat. The main advantage of Oligocat is given due to its reactional medium interaction. Initially, oligocat is a solid catalyst soluble in the alcoholic phase, acting as a homogeneous catalyst, providing better mass transfer of the catalytic groups to the reaction medium, and as the course of the reaction happens, Oligocat migrates to the glycerol phase, also providing the advantage of easy separation of the biodiesel. Oligocat was synthesized through polymerization of aromatic hydroxy acids, followed by a chemical functionalization applying the sulfonation technique. Characterization of the catalysts was carried out by infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC), and thermogravimetric analysis (TGA). The synthesized oligomers presented 5357 g·mol-1 (Mw) and 3909 g·mol-1 (Mn), with a moderate thermal resistance of approximately 175 °C. By sulfonation reaction, it was possible to obtain a high content of sulphonic groups of nearly 70 mol%, which provided the catalytic activity to the oligomeric matrix. With the mentioned physical-chemical properties, Oligocat is chemically designed to convert second generation feedstock to biodiesel efficiently. Preliminary investigation using Oligocat for biodiesel production resulted in conversion rates higher than 96.5 wt.%.

7.
Nutrients ; 12(4)2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32283715

RESUMO

Fasting is known to cause physiological changes in the endocrine pancreas, including decreased insulin secretion and increased reactive oxygen species (ROS) production. However, there is no consensus about the long-term effects of intermittent fasting (IF), which can involve up to 24 hours of fasting interspersed with normal feeding days. In the present study, we analyzed the effects of alternate-day IF for 12 weeks in a developing and healthy organism. Female 30-day-old Wistar rats were randomly divided into two groups: control, with free access to standard rodent chow; and IF, subjected to 24-hour fasts intercalated with 24-hours of free access to the same chow. Alternate-day IF decreased weight gain and food intake. Surprisingly, IF also elevated plasma insulin concentrations, both at baseline and after glucose administration collected during oGTT. After 12 weeks of dietary intervention, pancreatic islets displayed increased ROS production and apoptosis. Despite their lower body weight, IF animals had increased fat reserves and decreased muscle mass. Taken together, these findings suggest that alternate-day IF promote ß -cell dysfunction, especially in developing animals. More long-term research is necessary to define the best IF protocol to reduce side effects.


Assuntos
Tecido Adiposo/metabolismo , Ingestão de Alimentos , Jejum/efeitos adversos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Redução de Peso , Tecido Adiposo/patologia , Animais , Apoptose , Jejum/fisiologia , Feminino , Insulina/sangue , Secreção de Insulina , Músculos/metabolismo , Músculos/patologia , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo
8.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;78(4): 193-198, Apr. 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1098090

RESUMO

Abstract Objective: To compare the ways of evaluating arithmetic skills in Brazilian children with ADHD by combining three validated neuropsychological tests and determining whether they are sensitive to the methylphenidate treatment. Methods: Forty-two children (9‒12 years old) participated in the present study: 20 were children with ADHD (DSM-IV) and 22 were age-matched controls. A classification criterion was used for each test separately and one, for their combination to detect the presence of arithmetic difficulties at two time points: baseline (time 1); and when children with ADHD were taking 0.3‒0.5 mg/kg of methylphenidate (time 2). The study also assessed children's subtraction performance, combining parts of these tests. Results: Separately, the tests were only sensitive to differences between groups without medication. However, by combining the three neuropsychological tests, we observed a difference and detected a reduction in arithmetic difficulties associated with the methylphenidate treatment. The same effects were found in subtraction exercises, which require a borrowing procedure. Conclusions: The present study detected arithmetic difficulties in Brazilian children with ADHD and the effects of methylphenidate. Given this improvement in sensitivity, combining tests could be a promising alternative when working with limited samples.


Resumo Objetivo: Comparar as formas de avaliar as habilidades aritméticas em crianças brasileiras com TDAH, combinando três testes neuropsicológicos validados, e verificar se são sensíveis ao tratamento com metilfenidato. Métodos: Quarenta e duas crianças (9‒12 anos) participaram deste estudo: 20 eram crianças com TDAH (DSM-IV) e 22 eram controles pareados por idade. Usamos um critério de classificação para cada teste separadamente e outro para a combinação entre eles, visando detectar a presença de dificuldades aritméticas em dois momentos: início (tempo 1) e quando as crianças com TDAH estavam tomando 0,3‒0,5 mg/kg de metilfenidato (tempo 2). O estudo também avaliou o desempenho dessas crianças em operações de subtração, combinando partes desses testes. Resultados: Separadamente, os testes foram sensíveis apenas às diferenças entre os grupos sem medicação. Entretanto, ao combinar os três testes neuropsicológicos, foi possível observar uma diferença e detectar uma redução das dificuldades aritméticas associadas ao tratamento com metilfenidato. Os mesmos efeitos foram encontrados em exercícios de subtração que exigem o procedimento de empréstimo. Conclusões: O estudo foi capaz de detectar dificuldades aritméticas em crianças brasileiras com TDAH e os efeitos do metilfenidato. Dada essa melhora na sensibilidade, combinar testes poderia ser uma alternativa promissora ao trabalhar com amostras limitadas.


Assuntos
Humanos , Criança , Transtorno do Deficit de Atenção com Hiperatividade , Brasil , Estimulantes do Sistema Nervoso Central , Metilfenidato , Testes Neuropsicológicos
9.
Arq Neuropsiquiatr ; 78(4): 193-198, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32130296

RESUMO

OBJECTIVE: To compare the ways of evaluating arithmetic skills in Brazilian children with ADHD by combining three validated neuropsychological tests and determining whether they are sensitive to the methylphenidate treatment. METHODS: Forty-two children (9‒12 years old) participated in the present study: 20 were children with ADHD (DSM-IV) and 22 were age-matched controls. A classification criterion was used for each test separately and one, for their combination to detect the presence of arithmetic difficulties at two time points: baseline (time 1); and when children with ADHD were taking 0.3‒0.5 mg/kg of methylphenidate (time 2). The study also assessed children's subtraction performance, combining parts of these tests. RESULTS: Separately, the tests were only sensitive to differences between groups without medication. However, by combining the three neuropsychological tests, we observed a difference and detected a reduction in arithmetic difficulties associated with the methylphenidate treatment. The same effects were found in subtraction exercises, which require a borrowing procedure. CONCLUSIONS: The present study detected arithmetic difficulties in Brazilian children with ADHD and the effects of methylphenidate. Given this improvement in sensitivity, combining tests could be a promising alternative when working with limited samples.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Brasil , Estimulantes do Sistema Nervoso Central , Criança , Humanos , Metilfenidato , Testes Neuropsicológicos
10.
Arq. bras. neurocir ; 38(4): 324-327, 15/12/2019.
Artigo em Inglês | LILACS | ID: biblio-1362508

RESUMO

Vertex epidural hematomas (VEHs) are a special clinical entity due to their clinical presentation, vascular etiology and options of surgical approach. The clinical suspicion involves recognizing the mechanism of the injury and the correct visualization of the hematoma in computed tomography (CT) coronal sequences. In the present article, we describe a case of a very large (146 mL) VEH with central brain herniation, and provide a technical note on the surgical planning and treatment. A 34-year-old male patient was admitted to the hospital after an injury on the left superior parietal region. The Glasgow coma scale score was 6, and the left pupil of the patient was dilated. The CT scan showed a large epidural hematoma on the vertex between the coronal e lambdoid sutures, and a fracture over the sagittal suture. During the surgery, multiple burr holes were made laterally to the sagittal suture, and after inspection and no visualization of bleeding in the superior sagittal sinus (SSS), we performed a standard biparietal craniotomy. The patient was discharged three days after the surgery without any deficits. Currently, with the improvement in imaging modalities,more cases of VEH are being identified. Identifying the etiology prior to the craniotomy is challenging in severe cases. Tears in the SSS can bleed profusely, and they demand strategies during the craniotomy.With multiple burr holes parallel to the sagittal suture, we can visualize whether there is bleeding in the SSS and design a craniotomy with or without a central osseous bridge to anchor the dura. Neurosurgeons must be prepared to plan a surgical strategy in cases of large VEHs. Due to its rare frequency and bleeding risks, VEHs are considered challenging.


Assuntos
Humanos , Masculino , Adulto , Encefalocele/diagnóstico por imagem , Hematoma Epidural Craniano/cirurgia , Hematoma Epidural Craniano/complicações , Hematoma Epidural Craniano/diagnóstico por imagem , Angiografia/métodos , Craniotomia/métodos , Traumatismos Craniocerebrais
12.
Biomed Res Int ; 2019: 2492315, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214612

RESUMO

Skin secretions of frogs have a high chemical complexity. They have diverse types of biomolecules, such as proteins, peptides, biogenic amines, and alkaloids. These compounds protect amphibians' skin against growth of bacteria, fungi, and protozoa and participate in defense system against attack from predators. Therewith, this work performed biochemical and biological profile of macroglands parotoid secretion from cane toad. For poison analysis, we performed molecular exclusion and reverse phase chromatography, electrophoresis, and mass spectrometry. Antimicrobial, antiplasmodial, leishmanicidal, cytotoxicity, genotoxicity, and inflammatory activity of crude and/or fractions of R. marina secretion were also evaluated. Fractionation prior to filtration from poison showed separation of low mass content (steroids and alkaloids) and high molecular mass (protein). Material below 10 kDa two steroids, marinobufagin and desacetylcinobufagin, was detected. Crude extract and fractions were active against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Plasmodium falciparum, Leishmania guyanensis, and Leishmania braziliensis. Crude extract was also active against cancer cells although it was not cytotoxic for normal cells. This extract did not show significant DNA damage but it showed an important inflammatory effect in vivo. The information obtained in this work contributes to the understanding of the constituents of R. marina secretion as well as the bioactive potential of these molecules.


Assuntos
Antibacterianos , Bufanolídeos , Glândula Parótida/metabolismo , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pele/metabolismo , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bufanolídeos/química , Bufanolídeos/metabolismo , Bufanolídeos/farmacologia , Bufo marinus
13.
Rev Diabet Stud ; 15: 16-25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31132077

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is the main cause of mortality in type 2 diabetes (T2D). Exercise can reduce the risk factors associated with CVD in T2D patients. However, research evaluating its beneficial effects in these patients has used different measurement protocols and types of exercise, complicating comparison. AIM: To assess the effects of resistance training (RT) and combined training (CT) on the vascular function of T2D patients. METHODS: A database search (MEDLINE, Scopus, and Web of Science) was performed to identify relevant articles that were published up to August 2017. Only original studies evaluating the effects of RT or CT interventions on vascular function in T2D patients were included. The articles were reviewed independently by at least three reviewers. The Cochrane guidelines were used to assess the methodological quality of the studies. Fourteen studies were finally included. Two studies only used RT and twelve studies used CT as intervention strategy. RESULTS AND CONCLUSIONS: The results show that resistance training is a useful means for primary treatment of vascular diseases and maintenance of vascular function in T2D patients. However, more studies are necessary to gain full knowledge of the beneficial effects and to identify tailored exercise plans to optimize these benefits. The information provided in this review may help to improve current treatment of vascular diseases in T2D patients and to design future studies.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Treinamento Resistido , Doenças Vasculares/terapia , Idoso , Vasos Sanguíneos/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/terapia , Terapia por Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Doenças Vasculares/etiologia , Doenças Vasculares/fisiopatologia
14.
Biomed Res Int, v. 2019, 2492315, fev. 2019
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2756

RESUMO

Skin secretions of frogs have a high chemical complexity. They have diverse types of biomolecules, such as proteins, peptides, biogenic amines, and alkaloids. These compounds protect amphibians’ skin against growth of bacteria, fungi, and protozoa and participate in defense system against attack from predators. Therewith, this work performed biochemical and biological profile of macroglands parotoid secretion from cane toad. For poison analysis, we performed molecular exclusion and reverse phase chromatography, electrophoresis, and mass spectrometry. Antimicrobial, antiplasmodial, leishmanicidal, cytotoxicity, genotoxicity, and inflammatory activity of crude and/or fractions of R. marina secretion were also evaluated. Fractionation prior to filtration from poison showed separation of low mass content (steroids and alkaloids) and high molecular mass (protein). Material below 10 kDa two steroids, marinobufagin and desacetylcinobufagin, was detected. Crude extract and fractions were active against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Plasmodium falciparum, Leishmania guyanensis, and Leishmania braziliensis. Crude extract was also active against cancer cells although it was not cytotoxic for normal cells. This extract did not show significant DNA damage but it showed an important inflammatory effect in vivo. The information obtained in this work contributes to the understanding of the constituents of R. marina secretion as well as the bioactive potential of these molecules.

15.
Sci Rep ; 8(1): 13061, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30166558

RESUMO

The exposure of pancreatic islets to high glucose is believed to be one of the causal factors of the progressive lowering of insulin secretion in the development of type 2 diabetes. The progression of beta cell failure to type 2 diabetes is preceded by an early positive increase in the insulin secretory response to glucose, which is only later followed by a loss in the secretion capacity of pancreatic islets. Here we have investigated the electrophysiological mechanisms underlying the early glucose-mediated gain of function. Rodent pancreatic islets or dispersed islet cells were cultured in medium containing either 5.6 (control) or 16.7 (high-glucose) mM glucose for 24 h after isolation. Glucose-stimulated insulin secretion was enhanced in a concentration-dependent manner in high glucose-cultured islets. This was associated with a positive effect on beta cell exocytotic capacity, a lower basal KATP conductance and a higher glucose sensitivity to fire action potentials. Despite no changes in voltage-gated Ca2+ currents were observed in voltage-clamp experiments, the [Ca2+]I responses to glucose were drastically increased in high glucose-cultured cells. Of note, voltage-dependent K+ currents were decreased and their activation was shifted to more depolarized potentials by high-glucose culture. This decrease in voltage-dependent K+ channel (Kv) current may be responsible for the elevated [Ca2+]I response to metabolism-dependent and independent stimuli, associated with more depolarized membrane potentials with lower amplitude oscillations in high glucose-cultured beta cells. Overall these results show that beta cells improve their response to acute challenges after short-term culture with high glucose by a mechanism that involves modulation not only of metabolism but also of ion fluxes and exocytosis, in which Kv activity appears as an important regulator.


Assuntos
Técnicas de Cultura de Células , Glucose/toxicidade , Células Secretoras de Insulina/metabolismo , Animais , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Capacitância Elétrica , Exocitose/efeitos dos fármacos , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Espaço Intracelular/metabolismo , Canais KATP/metabolismo , Canais de Potássio/metabolismo , Ratos Wistar , Fatores de Tempo
16.
Environ Monit Assess ; 190(5): 263, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29616342

RESUMO

In sewage treatment plants, physicochemical parameters are highly controlled since treated sewage can be returned to water bodies or reused. In addition, pollutants such as heavy metals also deserve attention due to their potential toxicity. In general, these characteristics of sewage and treated water are evaluated independently, with the support of Brazilian legislation that does not require a routine for the analysis of metals as frequent as for the physicochemical parameters. In this work, 66 samples of raw sewage, treated sewage, and effluents from two treatment plants in the city of Bauru, São Paulo, Brazil, were evaluated to assess the efficiency of the treatment plants in the removal of metals. In addition, the influence of these pollutants on the quantification of physicochemical parameters was evaluated. The quantification of metals was performed using inductively coupled plasma optical spectroscopy (ICP-OES), and Spearman's test was applied to evaluate correlation between physicochemical parameters and metal content. The main metals found in the samples were Ba, Mn, Zn, Cu, Se, Fe, and Al. The results indicate that concentrations of metals in the aquatic environment can significantly affect the physicochemical parameters, since high concentrations of metals can interfere mainly in the pH, chemical oxygen demand, and dissolved oxygen.


Assuntos
Metais Pesados/análise , Esgotos/química , Eliminação de Resíduos Líquidos , Brasil , Monitoramento Ambiental , Esgotos/análise , Purificação da Água
17.
Noise Health ; 20(92): 23-26, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29457603

RESUMO

n work environments, different physical and chemical agents that may pose a risk to workers' hearing health coexist. In this context, occupational hearing loss stands out. It has mostly been attributed to only noise exposure, although there are other agents, that is, pesticides that might contribute to occupational hearing loss. In this report, two cases will be presented that consider rural workers exposed to pesticides and intense noise generated by an adapted rudimentary vehicle. The noise measured in this vehicle was 88.3 dBA up to 93.4 dBA. Pure-tone audiometry, distortion product otoacoustic emissions, and high-frequency audiometry tests were performed. This report is unusual because of the short time of exposure to noise and pesticides and the hearing loss found, indicating a synergy between those agents.


Assuntos
Perda Auditiva Provocada por Ruído/etiologia , Ruído Ocupacional/efeitos adversos , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Praguicidas/efeitos adversos , Adulto , Audiometria , Brasil , Fazendeiros , Humanos , Masculino , Veículos Automotores , População Rural , Local de Trabalho , Adulto Jovem
18.
Am J Orthod Dentofacial Orthop ; 153(1): 118-130, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29287638

RESUMO

This case report describes the orthodontic retreatment a patient with a skeletal Class III malocclusion. The clinical examination showed a concave profile caused by a retruded maxilla and a prognathic mandible, an occlusal cant, and absence of all first premolars. A surgery-first approach was combined with skeletal anchorage implants in the maxillary arch and tandem mechanics. The esthetic facial profile, pleasant smile, appropriate occlusion, and overall good treatment outcomes remained stable 5 years after active orthodontic treatment.


Assuntos
Má Oclusão Classe III de Angle/terapia , Procedimentos de Ancoragem Ortodôntica , Procedimentos Cirúrgicos Ortognáticos , Técnicas de Movimentação Dentária , Terapia Combinada , Humanos , Masculino , Má Oclusão Classe III de Angle/cirurgia , Mandíbula , Dente Molar , Procedimentos de Ancoragem Ortodôntica/métodos , Retratamento , Adulto Jovem
19.
Int Wound J ; 14(6): 1019-1024, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28488305

RESUMO

The aim of this study was to systematically review the use of medicinal plants for the treatment of varicose ulcers. The databases used in the search were: Medline/Pubmed, Scopus, Cinhal, Lilacs and Web of Science. The selection process was divided into two phases: the reading of titles and abstracts and the full reading of selected articles. The item description was compared with the checklist of the Consolidated Standards of Reporting Trials. The initial search produced 3505 articles and seven were selected for inclusion in the systematic review. Of the included studies, 7 (100%) evaluated the reduction of the ulcer area, 4 (57·14%) evaluated reepithelisation, 2 (28·57%) evaluated bacterial flora and 1 (14·28%) evaluated the oxygen pressure and percutaneous carbon dioxide. The level of evidence rating indicated that five studies (71·42%) were rated at level 2 and two (28·57%) were rated at level 3. The quality assessment was performed using the Jadad scale, which is prevalent in the literature. The quality score of the Jadad questionnaire ranges from 0 to 5; here, the studies analysed had an average of 2·5. A meta-analysis was performed on two studies that analysed the effects of Mimosa tenuiflora hydrogel in the treatment of venous ulcer and included 42 patients with a mean age of 60·5 years and a mean duration of treatment of 10·5 weeks. Heterogeneity was assessed using I2 ; we obtained a high value of 84%. We concluded that, despite the efficacy of the incorporation of Ageratina pichinchensis into the gel, the hydrogel that incorporated M. tenuiflora appeared to be a promising candidate for the management of venous ulcers.


Assuntos
Antibacterianos/uso terapêutico , Extratos Vegetais/uso terapêutico , Plantas Medicinais/química , Úlcera Varicosa/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Biomed Pharmacother ; 91: 739-747, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28499245

RESUMO

BACKGROUND: Due to its unclear pathophysiology, the pharmacological treatment of fibromyalgia is a challenge for researchers. Studies using medicinal plants, such as those from the genus Lippia, complexed with cyclodextrins (CDs) have shown innovative results. OBJECTIVE: The present research intended to evaluate the effect of an inclusion complex containing ß-cyclodextrin (ßCD) inclusion complex with Lippia grata (LG) essential oil in a chronic musculoskeletal pain model, its central activity and its possible interaction with neurotransmitters involved in pain. METHODS: After acid saline-induced chronic muscle pain, male mice were evaluated for primary and secondary hyperalgesia and muscle strength. Moreover, an antagonist assay was performed to assess the possible involvement of the opioidergic, serotonergic and noradrenergic pathways. In addition, Fos protein in the spinal cord was assessed, and a docking study and antioxidant assays were performed. RESULTS: The treatment with LG-ßCD, especially in the dose of 24mg/kg, was able to significantly decrease (p<0.05) the paw withdrawal and muscle threshold. Furthermore, LG-ßCD was shown to affect the opioidergic and serotonergic pathways. There were no significant changes in muscle strength. Fos protein immunofluorescence showed a significant decrease in expression in the dorsal horn of the spinal cord. The main compounds of LG showed through the docking study interaction energies with the alpha-adrenergic and µOpioid receptors. In all antioxidant assays, LG exhibited stronger antioxidant activities than LG-ßCD. CONCLUSION: This study suggested that LG-ßCD could be considered as a valuable source for designing new drugs in the treatment of chronic pain, especially musculoskeletal pain.


Assuntos
Antioxidantes/análise , Dor Crônica/tratamento farmacológico , Hiperalgesia/tratamento farmacológico , Lippia/química , Simulação de Acoplamento Molecular , Dor Musculoesquelética/tratamento farmacológico , Óleos Voláteis/uso terapêutico , beta-Ciclodextrinas/química , Analgésicos/uso terapêutico , Animais , Dor Crônica/complicações , Modelos Animais de Doenças , Hiperalgesia/complicações , Masculino , Metisergida/uso terapêutico , Camundongos , Dor Musculoesquelética/complicações , Naloxona/uso terapêutico , Folhas de Planta/química , Proteínas Proto-Oncogênicas c-fos/metabolismo , Corno Dorsal da Medula Espinal/efeitos dos fármacos , Corno Dorsal da Medula Espinal/metabolismo , Corno Dorsal da Medula Espinal/patologia , Ioimbina/uso terapêutico
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