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1.
Cell Signal ; 120: 111241, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38825173

RESUMO

Cardiac fibroblasts (CF) are mesenchymal-type cells responsible for maintaining the homeostasis of the heart's extracellular matrix (ECM). Their dysfunction leads to excessive secretion of ECM proteins, tissue stiffening, impaired nutrient and oxygen exchange, and electrical abnormalities in the heart. Additionally, CF act as sentinel cells in the cardiac tissue microenvironment, responding to various stimuli that may affect heart function. Deleterious stimuli induce an inflammatory response in CF, increasing the secretion of cytokines such as IL-1ß and TNF-α and the expression of cell adhesion molecules like ICAM1 and VCAM1, initially promoting damage resolution by recruiting immune cells. However, constant harmful stimuli lead to a chronic inflammatory process and heart dysfunction. Therefore, it is necessary to study the mechanisms that govern CF inflammation. NFκB is a key regulator of the cardiac inflammatory process, making the search for mechanisms of NFκB regulation and CF inflammatory response crucial for developing new treatment options for cardiovascular diseases. SGK1, a serine-threonine protein kinase, is one of the regulators of NFκB and is involved in the fibrotic effects of angiotensin II and aldosterone, as well as in CF differentiation. However, its role in the CF inflammatory response is unknown. On the other hand, many bioactive natural products have demonstrated anti-inflammatory effects, but their role in CF inflammation is unknown. One such molecule is boldine, an alkaloid obtained from Boldo (Peumus boldus), a Chilean endemic tree with proven cytoprotective effects. However, its involvement in the regulation of SGK1 and CF inflammation is unknown. In this study, we evaluated the role of SGK1 and boldine in the inflammatory response in CF isolated from neonatal Sprague-Dawley rats. The involvement of SGK1 was analyzed using GSK650394, a specific SGK1 inhibitor. Our results demonstrate that SGK1 is crucial for LPS- and IFN-γ-induced inflammatory responses in CF (cytokine expression, cell adhesion molecule expression, and leukocyte adhesion). Furthermore, a conditioned medium (intracellular content of CF subject to freeze/thaw cycles) was used to simulate a sterile inflammation condition. The conditioned medium induced a potent inflammatory response in CF, which was completely prevented by the SGK1 inhibitor. Finally, our results indicate that boldine inhibits both SGK1 activation and the CF inflammatory response induced by LPS, IFN-γ, and CF-conditioned medium. Taken together, our results position SGK1 as an important regulator of the CF inflammatory response and boldine as a promising anti-inflammatory drug in the context of cardiovascular diseases.


Assuntos
Aporfinas , Fibroblastos , Proteínas Imediatamente Precoces , NF-kappa B , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Animais , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ratos , Aporfinas/farmacologia , Inflamação/metabolismo , Inflamação/patologia , Miocárdio/patologia , Miocárdio/metabolismo , Células Cultivadas , Ratos Sprague-Dawley
2.
J Hum Nutr Diet ; 34(2): 402-412, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33098177

RESUMO

BACKGROUND: Whether a patient's outcomes are better when receiving nutritional counselling during cardiac rehabilitation (CR) has been scarcely described. We compared changes in weight, waist circumference (WC) and blood pressure (BP) in patients attending CR with and without nutritional counselling. METHODS: A retrospective analytical study was conducted in which two groups of patients who completed a phase II CR (36 sessions) were compared: CONTROL [n = 144, mean (SD) age = 59 (12) years, 17% females], comprising patients without nutritional counselling (attended between 2003 and 2009), and NUT [n = 128, mean (SD) age = 60 (13) years, 27% females], comprising patients with dietitian-delivered nutritional counselling (attended between 2010 and 2019). Repeated-measures analysis of variance was used to compare changes in weight, WC, and BP during CR between groups. Logistic regression models determined the probability of reducing weight and systolic BP (SBP). RESULTS: NUT group decreased weight [-1.3 (3.1) kg; P < 0.0001] and WC [-3.0 (3.8) cm; P < 0.0001] to a greater extent than CONTROL [weight: -0.4 (3.1) kg; P = 0.51; WC: -1.4 (4.5) cm; P = 0.02]. In CONTROL, 7% reduced ≥ 5% weight and 31% reduced ≥ 10 mmHg SBP, whereas, in the NUT group, 18% reduced ≥ 5% weight and 47% reduced ≥ 10 mmHg SBP. Patients in NUT (versus CONTROL) were more likely to lose ≥ 5% of weight (odds ratio = 4.27, 95% confidence interval = 1.69-10.80; P < 0.01) and reduce SBP ≥ 10 mmHg (odds ratio = 3.15, 95% confidence interval = 1.58-6.27; P < 0.01). CONCLUSIONS: Patients who received nutritional counselling during CR improved anthropometric measures and were more likely to lose weight and reduce SBP than patients without nutritional counselling.


Assuntos
Reabilitação Cardíaca , Pressão Sanguínea , Aconselhamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Circunferência da Cintura
3.
Free Radic Res ; 48(2): 129-36, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23967899

RESUMO

Nitrofurantoin is used in the antibacterial therapy of the urinary tract. This therapy is associated with various adverse effects whose mechanisms remain unclear. Diverse studies show that the nitro reductive metabolism of nitrofurantoin leads to ROS generation. This reaction can be catalyzed by several reductases, including the cytochrome P450 (CYP450) reductase. Oxidative stress arising from this nitro reductive metabolism has been proposed as the mechanism underlying the adverse effects associated with nitrofurantoin. There is, however, an apparent paradox between these findings and the ability of nitrofurantoin to inhibit lipid peroxidation provoked by NADPH in rat liver microsomes. This work was aimed to show the potential contribution of different enzymatic systems to the metabolism of this drug in rat liver microsomes. Our results show that microsomal lipid peroxidation promoted by NADPH is inhibited by nitrofurantoin in a concentration-dependent manner. This suggests that the consumption of NADPH in microsomes can be competitively promoted by lipid peroxidation and nitrofurantoin metabolism. The incubation of microsomes with NADPH and nitrofurantoin generated 1-aminohidantoin. In addition, the biotransformation of a classical substrate of CYP450 oxidative system was competitively inhibited by nitrofurantoin. These results suggest that nitrofurantoin is metabolized through CYP450 system. Data are discussed in terms of the in vitro redox metabolism of nitrofurantoin.


Assuntos
Anti-Infecciosos Urinários/metabolismo , Microssomos Hepáticos/metabolismo , NADP/fisiologia , Nitrofurantoína/metabolismo , Estresse Oxidativo , Animais , Biotransformação , Sistema Enzimático do Citocromo P-450/metabolismo , Hidantoínas/metabolismo , Peroxidação de Lipídeos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Oxirredução , Ratos , Ratos Sprague-Dawley
4.
Amino Acids ; 42(6): 2079-88, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21607746

RESUMO

The role of the titanium dioxide (rutile and anatase) with and without room light on the thermal synthesis of the glycine-L-glutamine (Gly-Gln) polymer is described. The efficiency in percentage of polymerization with room light was increased in 6% in the presence of rutile and in 23% in the presence of anatase. The thermal synthesis in the molten state was carried out in the absence and presence of both oxides. In all cases, the vibrational spectra showed characteristic group frequencies corresponding to a polypeptide structure. No spectral differences were observed by room light effect on the polymer on rutile. However, the polymer obtained in the presence of anatase and room light shows spectral changes associated with the formation of shorter new abundant and conformationally different species compared with the original polymer. The SEM-EDX characterization of the solid phase involved in the thermal synthesis showed that the morphology of the polypeptide is different in the presence of rutile compared to anatase. The SDS-PAGE and GPC results suggest that smaller chains are formed in the presence of both oxides and the distribution of the size and weight of each polymer molecule is completely different when the condensation is performed in the presence of anatase or rutile. Nuclear magnetic resonance analyses confirmed the incorporation of both Gly and Gln residues in the polymers, with a prevalence of Gly. Both possible sequences N-GlyGln-C and N-GlnGly-C were also detected.


Assuntos
Dipeptídeos/química , Glutamina/química , Glicina/química , Peptídeos/síntese química , Titânio/química , Eletroforese em Gel de Poliacrilamida , Luz , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Modelos Químicos , Peso Molecular , Tamanho da Partícula , Polimerização
5.
J Appl Toxicol ; 29(8): 695-702, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19629952

RESUMO

Copper toxicity has been associated to the capacity of free copper ions to catalyze the production of superoxide anion and hydroxyl radical, reactive species that modify the structure and/or function of biomolecules. In addition, nonspecific Cu2+-binding to thiol enzymes, which modifies their catalytic activities, has been reported. Cytochrome P450 (CYP450) monooxygenase is a thiol protein that binds substrates in the first and limiting step of CYP450 system catalytic cycle, necessary for the metabolism of lipophilic xenobiotics. Therefore, copper ions have the potential to oxidize and bind to cysteinyl residues of this monooxygenase, altering the CYP450 system activity. To test this postulate, we studied the effect of Cu2+ alone and Cu2+/ascorbate in rat liver microsomes, to independently evaluate its nonspecific binding and its pro-oxidant effects, respectively. We assessed these effects on the absorbance spectrum of the monooxygenase, as a measure of structural damage, and p-nitroanisole O-demethylating activity of CYP450 system, as a marker of functional impairment. Data obtained indicate that Cu2+ could both oxidize and bind to some amino acid residues of the CYP450 monooxygenase but not to its heme group. The differences observed between the effects of Cu2+ and Cu2+/ascorbate show that both mechanisms are involved in the catalytic activity inhibition of CYP450 system by copper ions. The significance of these findings on the pharmacokinetics and pharmacodynamics of drugs is discussed.


Assuntos
Cobre/toxicidade , Inibidores das Enzimas do Citocromo P-450 , Inibidores Enzimáticos/toxicidade , Oxidantes/toxicidade , Animais , Quelantes , Cobre/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Inibidores Enzimáticos/metabolismo , Glutationa/metabolismo , Cinética , Fígado/enzimologia , Masculino , Microssomos Hepáticos/enzimologia , Oxidantes/metabolismo , Oxirredutases O-Desmetilantes/antagonistas & inibidores , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Espectrofotometria
6.
Nanotechnology ; 19(22): 225202, 2008 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-21825754

RESUMO

A nanocrystalline Si-based paste was successfully tested as the light emitting material in a field emission display test device that employed a film of carbon nanofibers as the electron source. Stable emission in the 550-850 nm range was obtained at 16 V µm(-1). This relatively low field required for intense cathodoluminescence (CL) from the PSi paste may lead to longer term reliability of both the electron emitting and the light emitting materials, and to lower power consumption. Here we describe the synthesis, characterization, and analyses of the light emitting nanostructured Si paste and the electron emitting C nanofibers used for building the device, including x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. The corresponding spectra and field emission curves are also shown and discussed.

7.
Comp Biochem Physiol C Toxicol Pharmacol ; 134(4): 465-72, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12727296

RESUMO

This study was undertaken to localize substance P-like immunoreactivity (SP) in the nerve fibers innervating the palate, identify the ganglion of the palatine nerve and determine whether it contains SP cell bodies, in the frog Rana pipiens. The palatine nerve which is a branch of the maxillo-mandibular subdivision of the trigeminal nerve was traced to the trigeminal ganglion that connects to the medulla by the trigeminal nerve root. Using an immunocytochemical method, SP containing fibers with varicosities were found in the connective tissue layer of the palate. Some of these fibers were observed adjacent to blood vessels to the epithelial layer of the palate in apparent innervation of the ciliated epithelial and mucus cells. SP-labeling was also observed in small to medium cells of the trigeminal ganglion. These results appear to support the pharmacological studies of SP on the regulation of mucociliary activity in the frog R. pipiens.


Assuntos
Palato/química , Palato/inervação , Substância P/análise , Gânglio Trigeminal/química , Animais , Imunoquímica , Palato/metabolismo , Rana pipiens , Substância P/metabolismo , Gânglio Trigeminal/metabolismo
8.
Sleep ; 20(1): 28-33, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9130331

RESUMO

The goals of this descriptive study were to determine what percentage of our treated narcoleptic subjects took their stimulant medications as prescribed and to examine the relationship between compliance and response to stimulant medications. Data obtained from a screening questionnaire, sleep diaries, and medical records showed that 22 of our 43 treated narcoleptic subjects reduced their dosage of stimulant medications or had not taken any stimulant medications during a 24-hour monitoring period during which they were expected to be on medication. Although we had expected better compliance among subjects who responded to stimulant medications (day-wake subjects), statistical testing revealed no significant differences between the two groups. Nor were there any significant differences in age, gender, or educational level when compliant and noncompliant subjects were compared. Only the type of drug prescribed (short versus long-acting stimulant) affected compliance; 39.4% of the subjects with prescriptions for dextroamphetamine or methylphenidate took the amount of medication prescribed compared to 87.5% of the subjects with prescriptions for pemoline.


Assuntos
Estimulantes do Sistema Nervoso Central/uso terapêutico , Dextroanfetamina/uso terapêutico , Metilfenidato/uso terapêutico , Narcolepsia/tratamento farmacológico , Cooperação do Paciente , Pemolina/uso terapêutico , Adolescente , Adulto , Estimulantes do Sistema Nervoso Central/administração & dosagem , Dextroanfetamina/administração & dosagem , Feminino , Humanos , Masculino , Metilfenidato/administração & dosagem , Pemolina/administração & dosagem , Vigília
9.
Biochim Biophys Acta ; 1121(1-2): 97-103, 1992 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-1599956

RESUMO

Estramustine-phosphate (EMP), a phosphorylated conjugate of estradiol and nor-nitrogen mustard binds to microtubule-associated proteins MAP-2 and tau. It was shown that this estramustine derivative inhibits the binding of the C-terminal tubulin peptide beta-(422-434) to both MAP-2 and tau. This tubulin segment constitutes a main binding domain for these microtubule-associated proteins. Interestingly, estramustine-phosphate interacted with the synthetic tau peptides V187-G204 and V218-G235, representing two major repeats within the conserved microtubule-binding domain on tau and also on MAP-2. This observation was corroborated by the inhibitory effects of estramustine-phosphate on the tau peptide-induced tubulin assembly into microtubules. On the other hand, the nonphosphorylated drug estramustine failed to block the MAP peptide-induced assembly, indicating that the negatively charged phosphate moiety of estramustine-phosphate is of importance for its inhibitory effect. These findings suggest that the molecular sites for the action of estramustine-phosphate are located within the microtubule binding domains on tau and MAP-2.


Assuntos
Estramustina/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Tubulina (Proteína)/metabolismo , Proteínas tau/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Encéfalo/metabolismo , Bovinos , Cinética , Proteínas Associadas aos Microtúbulos/química , Proteínas Associadas aos Microtúbulos/ultraestrutura , Dados de Sequência Molecular , Peptídeos/síntese química , Peptídeos/metabolismo , Sequências Repetitivas de Ácido Nucleico , Proteínas tau/química , Proteínas tau/ultraestrutura
10.
Dev Genet ; 12(5): 362-70, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1806332

RESUMO

A long-lived (L) strain of Drosophila melanogaster, derived from a normal-lived (R) strain by artificial selection, has a significantly different adult longevity. Previous work has shown that 1) the two strains age in the same manner, 2) the major genes responsible for much of the L strain's extended longevity are located on the 3rd chromosome, and 3) the extended longevity phenotype is significantly modulated by the larval environment. In this report, we investigate the resistance of the L and R strains to the lethal effects of dietary paraquat. We show that, within the limitations of our described chromosomal and environmental manipulations, the extended longevity phenotype always accompanies the phenotype of elevated paraquat resistance. In addition, reversed selection applied to the L strain results in the simultaneous decrease of both life span and paraquat resistance. Thus, the presence or absence of the latter phenotype may be used as a bioassay for the presence or absence of the extended longevity phenotype, without any necessary implication of causality. Use of this bioassay should greatly speed up the genetic analysis of this system by allowing us to identify long-lived animals at a young age. Finally, we show that the age-related loss of elevated paraquat resistance in both strains precedes all the other age-related functional decrements which we have previously noted in this system.


Assuntos
Drosophila melanogaster/genética , Longevidade/genética , Paraquat/farmacologia , Animais , Bioensaio/métodos , Cromossomos , Drosophila melanogaster/efeitos dos fármacos , Resistência a Medicamentos/genética , Meio Ambiente , Feminino , Masculino , Especificidade da Espécie
11.
Biochim Biophys Acta ; 1040(3): 382-90, 1990 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-1699604

RESUMO

The structural-functional aspects of the tubulin binding domain on the microtubule-associated protein MAP-2, and its relationship with the tubulin binding domain on tau, were studied using anti-idiotypic antibodies that react specifically with the epitope(s) on MAPs involved in their interaction with tubulin in addition to other tau and MAP-2 specific antibodies. Previous studies showed that MAP-2 and tau share common binding sites on tubulin defined by the peptide sequences alpha (430-441) and beta (422-434) of tubulin subunits. Furthermore, binding experiments revealed the existence of multiple sites for the interaction of the alpha- and beta-tubulin peptides with MAP-2 and tau. Most recent studies showed that the synthetic tau peptide Val187-Gly204 (VRSKIGSTENLKHQPGGG) from the repetitive sequence on tau defines a tubulin binding site on tau. Our present immunological studies using anti-idiotypic antibodies which interact with the synthetic tau peptide and antibodies against the Val187-Gly204 tau peptide indicate that MAP-2 and tau share common antigenic determinants at the level of their respective tubulin binding domains. These antigenic determinants appear to be present in the 35 kDa tubulin binding fragment of MAP-2 and in 18-20 kDa chymotryptic fragments containing the tubulin binding site(s) on MAP-2. These findings, along with structural information on these proteins, provide strong evidence in favor of the hypothesis that tubulin binding domains on MAP-2 and tau share similar structural features.


Assuntos
Proteínas Associadas aos Microtúbulos/imunologia , Tubulina (Proteína)/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Anti-Idiotípicos/imunologia , Sítios de Ligação , Bovinos , Epitopos , Técnicas In Vitro , Substâncias Macromoleculares , Proteínas Associadas aos Microtúbulos/metabolismo , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Mapeamento de Peptídeos , Proteínas tau
12.
Artigo em Inglês | MEDLINE | ID: mdl-2859949

RESUMO

Brief (2-5 msec) electrical pulses applied to the primary spines of the sea urchin Diadema antillarum elicit graded action potentials (ap's). These ap's can be attributed to the electrical activity of a set of 14-21 bundles of neurites, each comprising 1000 processes near the spine base and tapering towards the spine tip. The shape of the ap's varies from a simple diphasic deflection to a complex waveform with 6 or more components. Peak-to-peak amplitude is less than 1mV. The ap's are conducted at a uniform speed of ca. 27 cm/sec. The ap's are not affected by tetrodotoxin (1 microgram/ml) and continue to be produced in Na-free artificial sea water (ASW). The amplitude of the ap's is greatly reduced or totally abolished in Ca-free ASW. However, some electrical activity may continue in the absence of external Ca, due to release of Ca2+ ions from the calcium carbonate crystals of the spine shaft. Replacing the Ca content of ASW by barium ions causes an irreversible blockade of the ap's. Spines equilibrated with ASW containing Sr2+ ions instead of Ca2+ produce ap's of increased amplitude (up to X 2). The ap's are blocked by La3+, Co2+, Cd2+ (2-5 mM) and by the organic Ca channel blocker Bepridil (2 mM). We conclude that the spinal ap's are due to the summation of Ca spikes produced by the activation of Ca channels which are blocked by barium and have a high affinity for, or permeability to Sr vs Ca.


Assuntos
Axônios/fisiologia , Ouriços-do-Mar/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Bário/farmacologia , Bepridil , Cádmio/farmacologia , Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Cobalto/farmacologia , Condutividade Elétrica , Estimulação Elétrica , Lantânio/farmacologia , Manganês/farmacologia , Pirrolidinas/farmacologia , Estrôncio/farmacologia , Verapamil/farmacologia
15.
Managua; Comisaria de la Mujer y la Niñez. Policía Naiconal. Movimiento de Mujeres María Elena Cuadra; s.f. 34 p. ilus.
Monografia em Espanhol | LILACS | ID: lil-446190

RESUMO

En el documento se abordan los pasos para que las mujeres que han sido victimas de violencia intrafamiliar puedan interponer la denuncia ante la Comisaria de la Mujer. Menciona los tipos de agresiones; así como algunos concepto de ciertos términos: delito; violencia; asesinato; rapto; abusos deshonestos; corrupción, incesto. También incluye el testimonio de una mujer vivió el maltrato conjugal.


Assuntos
Abuso Sexual na Infância/prevenção & controle , Incesto , Masoquismo , Proteção Pessoal , Estupro , Assédio Sexual , Violência Doméstica/legislação & jurisprudência , Violência Doméstica/prevenção & controle , Violência/legislação & jurisprudência , Violência/prevenção & controle , Saúde da Mulher , Direitos da Mulher
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