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1.
Nutr Metab Cardiovasc Dis ; 29(1): 69-78, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30459074

RESUMO

BACKGROUND AND AIMS: Polyphenol-rich diets have been associated with reduced risk of cardiovascular disease (CVD). However, few prospective epidemiological studies have examined the relationship between classes of ingested polyphenols and risk of CVD. Our aim was to evaluate the association between polyphenol intake and risk of major cardiovascular events in a prospective Spanish cohort. METHODS AND RESULTS: We included 17,065 university graduates (60.7% women, mean age: 37.2 years, age range: 20-89) followed-up for a mean of 10.1 years. Polyphenol intake was assessed at baseline using a validated semi-quantitative 136-item food frequency questionnaire and matching food consumption data with the Phenol-Explorer database. Cox proportional hazards models were used to estimate the adjusted hazard ratios (HR) and 95% confidence intervals (95% CI) for incident cardiovascular events (myocardial infarction, stroke or cardiovascular death). Cherries, chocolate, coffee, apples, and olives were the major sources of variability in polyphenol intake. Participants with higher flavonoids intake (fifth quintile) had a 47% lower incidence of cardiovascular events compared to those in the lowest quintile (HR: 0.53, 95% CI: 0.29-0.98; P for trend = 0.09) after adjusting for potential confounders. The results were non-significant for other polyphenol types. CONCLUSION: The intake of flavonoids showed an inverse association with risk of cardiovascular events in a prospective cohort of Spanish middle-aged adult university graduates. REGISTRATION NUMBER FOR CLINICAL TRIALS: NCT02669602 in Clinical Trials.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta , Polifenóis/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Inquéritos sobre Dietas , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Polifenóis/classificação , Estudos Prospectivos , Fatores de Proteção , Fatores de Risco , Espanha/epidemiologia , Estudantes , Fatores de Tempo , Universidades , Adulto Jovem
2.
Nitric Oxide ; 64: 31-38, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28087360

RESUMO

BACKGROUND: and purpose: The peptide PnPP-19, derived from the spider toxin PnTx2-6 (renamed as δ-CNTX-Pn1c), potentiates erectile function by activating the nitrergic system. Since NO has been studied as an antinociceptive molecule and PnPP-19 is known to induce peripheral antinociception, we intended to evaluate whether PnPP-19 could induce peripheral antinociception through activation of this pathway. EXPERIMENTAL APPROACH: Nociceptive thresholds were measured by paw pressure test. PGE2 (2 µg/paw) was administered intraplantarly together with PnPP-19 and inhibitors/blockers of NOS, guanylyl cyclase and KATP channels. The nitrite concentration was accessed by Griess test. The expression and phosphorylation of eNOS and nNOS were determined by western blot. KEY RESULTS: PnPP-19 (5, 10 and 20 µg/paw) induced peripheral antinociception in rats. Administration of NOS inhibitor (L-NOarg), selective nNOS inhibitor (L-NPA), guanylyl cyclase inhibitor (ODQ) and the blocker of KATP (glibenclamide) partially inhibited the antinociceptive effect of PnPP-19 (10 µg/paw). Tissue nitrite concentration increased after PnPP-19 (10 µg/paw) administration. Expression of eNOS and nNOS remained the same in all tested groups, however the phosphorylation of nNOS Ser852 (inactivation site) increased and phosphorylation of eNOS Ser1177 (activation site) decreased after PGE2 injection. Administration of PnPP-19 reverted this PGE2-induced effect. CONCLUSIONS AND IMPLICATIONS: The peripheral antinociceptive effect induced by PnPP-19 is resulting from activation of NO-cGMP-KATP pathway. Activation of eNOS and nNOS might be required for such effect. Our results suggest PnPP-19 as a new drug candidate to treat pain and reinforce the importance of nNOS and eNOS activation, as well as endogenous NO release, for induction of peripheral antinociception.


Assuntos
Analgésicos/farmacologia , GMP Cíclico/metabolismo , Canais KATP/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Peptídeos/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Pé/fisiopatologia , Masculino , Óxido Nítrico Sintase Tipo I/análise , Óxido Nítrico Sintase Tipo III/análise , Manejo da Dor , Sistema Nervoso Periférico/efeitos dos fármacos , Fosforilação , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Venenos de Aranha
3.
J Affect Disord ; 284: 183-189, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33607508

RESUMO

BACKGROUND: Depression is a major public health concern worldwide and its association with metabolic syndrome (MetS) remains unclear. Thus, we prospectively examined the association between depression and the risk of MetS, according to different diagnosis criteria. METHODS: This study included 9,237 participants of a Spanish dynamic prospective cohort of adult university graduates [mean (SD) age: 36.7 year (10.7)], initially free of any specific criterion of MetS, who were followed-up for a median of 8.3 years. The exposure variables were medical diagnosis of depression at baseline or in the first 2-year follow-up questionnaire. The outcome variable was the incidence of MetS, assessed according to each of three different criteria proposed by: International Diabetes Federation (IDF); National Cholesterol Education Program's Adult Treatment Panel III (NCEP-ATP III); IDF/NCEP-ATP III (updated harmonizing definition). Multivariable-adjusted Relative Risks (RR) of new-onset MetS and their 95% Confidence Intervals (95% CI) were estimated, using Poisson regression models. RESULTS: The cumulative incidences of MetS were 475 cases (IDF definition), 288 cases (NCEP-ATP III definition) and 492 cases (update harmonized definition). No association was observed between baseline depression and incidence of MetS, but the presence of depression after 2-years of follow-up was significantly associated with a higher risk of new-onset MetS, according to NCEP-ATP III definition (multivariable-adjusted RR, 2.46; 95% CI, 1.06-5.67). LIMITATIONS: Diagnosis of depression and MetS were self-reported. CONCLUSIONS: In this large prospective cohort of Spanish middle-aged adult university graduates, a direct association between depression and the risk of MetS according to NCEP-ATP III definition was found.


Assuntos
Síndrome Metabólica , Adulto , Estudos de Coortes , Depressão/epidemiologia , Humanos , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco
4.
Cytotherapy ; 12(4): 478-90, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20230220

RESUMO

BACKGROUND AIMS: Stem cells derived from human adipose tissue (ASC) have the capacity for renewal, are easily obtained and have plasticity properties that allow them to differentiate into several cell types, including osteoblast cells. With the aim of understanding the issue of the osteogenic process and finding reliable biomarkers in cells undergoing the osteogeneic differentiation process, this work took advantage of a proteomic approach to identify proteins involved in osteogenesis. METHODS: For this purpose, ASC were analyzed under three conditions: S0, in the absence of stimulation; S1, with 2 weeks of osteogenic medium stimulation; and S2, with 4 weeks of osteogenic medium stimulation. The identification of ASC was carried out by flow cytometry using antibodies specific to known undifferentiated stem cell-surface markers. Cell viability, enzymatic activity, mineral deposition, collagen structure and production and gene analyzes were evaluated for each condition. RESULTS: Phenotypic modifications were observed during the in vitro osteogenic differentiation process by two-dimensional (2-D) differential image gel electrophoresis (DIGE). The proteins were identified by mass espectrometry in tandem (MS/MS) analyzes using Matrix-assisted laser desorption/ionization with TOF/TOF is a tandem mass spectrometry method where two time-of-flight mass spectrometers are used consecutively (MALDI-TOF/TOF). A total of 51 differentially expressed proteins was identified when comparing the three observed conditions. Sixteen different spots were identified in the S0 stage compared with S2, while 28 different spots were found in S2 compared with S0. S1 expressed seven different spots compared with S0 and S2. CONCLUSIONS: These findings suggest the involvement of several proteins directly related to the osteogenic pathway, which can be used to improve understanding of the osteogenic process.


Assuntos
Tecido Adiposo/citologia , Biomarcadores , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismo , Proteômica , Células Estromais/metabolismo , Tecido Adiposo/cirurgia , Adulto , Biomarcadores/metabolismo , Diferenciação Celular , Separação Celular , Células Cultivadas , Eletroforese em Gel Bidimensional , Feminino , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Células-Tronco Mesenquimais/citologia , Pessoa de Meia-Idade , Osteoblastos/citologia , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Células Estromais/citologia
5.
Amino Acids ; 39(1): 135-44, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19946788

RESUMO

LyeTx I, an antimicrobial peptide isolated from the venom of Lycosa erythrognatha, known as wolf spider, has been synthesised and its structural profile studied by using the CD and NMR techniques. LyeTx I has shown to be active against bacteria (Escherichia coli and Staphylococcus aureus) and fungi (Candida krusei and Cryptococcus neoformans) and able to alter the permeabilisation of L: -alpha-phosphatidylcholine-liposomes (POPC) in a dose-dependent manner. In POPC containing cholesterol or ergosterol, permeabilisation has either decreased about five times or remained unchanged, respectively. These results, along with the observed low haemolytic activity, indicated that antimicrobial membranes, rather than vertebrate membranes seem to be the preferential targets. However, the complexity of biological membranes compared to liposomes must be taken in account. Besides, other membrane components, such as proteins and even specific lipids, cannot be discarded to be important to the preferential action of the LyeTx I to the tested microorganisms. The secondary structure of LyeTx I shows a small random-coil region at the N-terminus followed by an alpha-helix that reached the amidated C-terminus, which might favour the peptide-membrane interaction. The high activity against bacteria together with the moderate activity against fungi and the low haemolytic activity have indicated LyeTx I as a good prototype for developing new antibiotic peptides.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Venenos de Aranha/química , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Candida/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Fosfatidilcolinas/antagonistas & inibidores , Estrutura Secundária de Proteína , Aranhas , Staphylococcus aureus/efeitos dos fármacos
6.
Nutr Metab Cardiovasc Dis ; 20(5): 359-65, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19683907

RESUMO

BACKGROUND AND AIMS: The consumption of tree nuts could reduce the risk of hypertension, but scarce research has been done to evaluate this potential association. We assessed the association between nut consumption and the incidence of hypertension among 9919 Spanish university graduates followed-up biennially for a median of 4.3 years. METHODS AND RESULTS: Food habits were assessed with a validated 136-item food-frequency questionnaire. Nut consumption was classified into four categories: rarely/never, 1-3/month, 1/week, and 2+/week. A participant was classified as an incident case of hypertension when, being free of hypertension at baseline, he/she subsequently reported a physician-made diagnosis of hypertension in at least one of the follow-up questionnaires. The incidence of hypertension was 12.4 per 1000 person-years. We found no association between nut consumption and incidence of hypertension after adjusting for sex, age and other dietary and non-dietary potential confounders (hazard ratio [HR] for those in the highest vs. lowest nut consumption category=0.77 [IC 95%: 0.46-1.30] p=0.795). Results were not modified when we stratified them analyses according to sex or to body mass index. CONCLUSION: Our data do not provide evidence for an inverse association between nut consumption and incident hypertension in our cohort. Further results from cohorts and trials with a higher baseline risk of hypertension should be obtained to test this relationship.


Assuntos
Hipertensão/epidemiologia , Nozes , Adulto , Estudos de Coortes , Dieta Mediterrânea , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Biochem Biophys Res Commun ; 371(3): 515-20, 2008 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-18445483

RESUMO

Using a proteomic approach, a new structural family of peptides was put in evidence in the venom of the yellow scorpion Tityus serrulatus. Tityus serrulatus Hypotensins (TsHpt) are random-coiled linear peptides and have a similar bradykinin-potentiating peptide (BPP) amino acid signature. TsHpt-I (2.7kDa), the first member of this family, was able to potentiate the hypotensive effects of bradykinin (BK) in normotensive rats. Using the C-terminal of this peptide as a template, a synthetic analog peptide (TsHpt-I([17-25])) was designed to held the BK-potentiating effect. A relevant hypotensive effect, independent on BK, was also observed on both TsHpt (native and synthetic). To better evaluate this hypotensive effect, we examined the vasorelaxation of aortic rings from male Wistar rats and the peptides were able to induce endothelium-dependent vasorelaxation dependent on NO release. Both TsHpt could not inhibit ACE activity. These peptides appear to exert their anti-hypertensive effect through NO-dependent and ACE-independent mechanisms.


Assuntos
Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Venenos de Escorpião/química , Venenos de Escorpião/farmacologia , Vasodilatadores/química , Vasodilatadores/farmacologia , Sequência de Aminoácidos , Animais , Anti-Hipertensivos/isolamento & purificação , Bradicinina/farmacologia , Sinergismo Farmacológico , Masculino , Dados de Sequência Molecular , Óxido Nítrico/metabolismo , Peptídeos/química , Peptídeos/isolamento & purificação , Peptídeos/farmacologia , Peptidil Dipeptidase A/efeitos dos fármacos , Ratos , Ratos Wistar , Venenos de Escorpião/isolamento & purificação , Vasodilatação , Vasodilatadores/isolamento & purificação
8.
Toxicon ; 51(7): 1197-206, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18397797

RESUMO

The venom of the spider Phoneutria nigriventer contains several toxins that have bioactivity in mammals and insects. Accidents involving humans are characterized by various symptoms including penile erection. Here we investigated the action of Tx2-6, a toxin purified from the P. nigriventer spider venom that causes priapism in rats and mice. Erectile function was evaluated through changes in intracavernosal pressure/mean arterial pressure ratio (ICP/MAP) during electrical stimulation of the major pelvic ganglion (MPG) of normotensive and deoxycorticosterone-acetate (DOCA)-salt hypertensive rats. Nitric oxide (NO) release was detected in cavernosum slices with fluorescent dye (DAF-FM) and confocal microscopy. The effect of Tx2-6 was also characterized after intracavernosal injection of a non-selective nitric oxide synthase (NOS) inhibitor, L-NAME. Subcutaneous or intravenous injection of Tx2-6 potentiated the elevation of ICP/MAP induced by ganglionic stimulation. L-NAME inhibited penile erection and treatment with Tx2-6 was unable to reverse this inhibition. Tx2-6 treatment induced a significant increase of NO release in cavernosum tissue. Attenuated erectile function of DOCA-salt hypertensive rats was fully restored after toxin injection. Tx2-6 enhanced erectile function in normotensive and DOCA-salt hypertensive rats, via the NO pathway. Our studies suggest that Tx2-6 could be important for development of new pharmacological agents for treatment of erectile dysfunction.


Assuntos
Neuropeptídeos/farmacologia , Neurotoxinas/farmacologia , Ereção Peniana/efeitos dos fármacos , Pênis/efeitos dos fármacos , Venenos de Aranha/farmacologia , Aranhas , Animais , Modelos Animais de Doenças , Sinergismo Farmacológico , Estimulação Elétrica , Disfunção Erétil/complicações , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/fisiopatologia , Hipertensão/induzido quimicamente , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Neuropeptídeos/isolamento & purificação , Neurotoxinas/isolamento & purificação , Óxido Nítrico/metabolismo , Ereção Peniana/fisiologia , Pênis/inervação , Pênis/metabolismo , Ratos , Ratos Wistar
9.
J Pharm Biomed Anal ; 40(1): 16-34, 2006 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-16326061

RESUMO

Sequential injection analysis is a well established tool for automation of pharmaceutical analysis. A short historical background of this technique is given as well as a brief discussion on the basic principles and potentials. The current applications of SIA in the pharmaceutical analysis are also described and discussed. The manifolds developed offer good analytical characteristics and are suitable for analysis of drug formulations, process analysis, drug-dissolution, drug-release testing and functional assays for screening potential drugs. The results obtained are in good agreement with those furnished by the application of the reference methods presented in the pharmacopoeias.


Assuntos
Indústria Farmacêutica , Tecnologia Farmacêutica/métodos , Disponibilidade Biológica , Calibragem , Química Farmacêutica , Eletroquímica , Soluções Farmacêuticas , Farmacopeias como Assunto , Solubilidade , Espectrometria de Fluorescência/métodos , Espectrofotometria/métodos
10.
Neuroscience ; 294: 29-37, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25766938

RESUMO

Proteomic profiles of the thalamus and the correlation between the rats' performance on a spatial learning task and differential protein expression were assessed in the thiamine deficiency (TD) rat model of Wernicke-Korsakoff syndrome. Two-dimensional gel-electrophoresis detected 320 spots and a significant increase or decrease in seven proteins. Four proteins were correlated to rat behavioral performance in the Morris Water Maze. One of the four proteins was identified by mass spectrometry as Voltage-Dependent Anion Channels (VDACs). The association of VDAC is evident in trials in which the rats' performance was worst, in which the VDAC protein was reduced, as confirmed by Western blot. No difference was observed on the mRNA of Vdac genes, indicating that the decreased VDAC expression may be related to a post-transcriptional process. The results show that TD neurodegeneration involves changes in thalamic proteins and suggest that VDAC protein activity might play an important role in an initial stage of the spatial learning process.


Assuntos
Transtornos Cognitivos/metabolismo , Síndrome de Korsakoff/metabolismo , Aprendizagem/fisiologia , Tálamo/metabolismo , Canais de Ânion Dependentes de Voltagem/metabolismo , Animais , Modelos Animais de Doenças , Síndrome de Korsakoff/genética , Masculino , Proteômica/métodos , Ratos Wistar , Percepção Espacial , Deficiência de Tiamina/genética
11.
Toxicon ; 39(7): 1009-19, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11223090

RESUMO

We report here the isolation by a two-step chromatographic procedure of two new toxins from the South American scorpion Tityus bahiensis. Their amino-acid sequences and some of their biological features were established. The two toxins have different biological properties. Toxin TbIT-I had almost no activity or pharmacological effects in vertebrate tissues whereas it was lethal to house flies (LD50 80.0 ng/house fly). In contrast, Tb2-II was active against both mammals (intracerebroventricular injection of 100 ng/mouse was lethal) and insects (LD50 40.0 ng/house fly). The amino-acid sequences of these toxins were established and found to be similar (60-95%) to previously described beta-toxins from the Tityus genus. Based on the available comparative information, this study attempts identify possible structure-function relationships that may be responsible for the differences in bioactivity displayed by these toxins.


Assuntos
Insetos/fisiologia , Venenos de Escorpião/química , Escorpiões/fisiologia , Toxinas Biológicas/química , Toxinas Biológicas/toxicidade , Sequência de Aminoácidos , Animais , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Gryllidae , Moscas Domésticas , Ativação do Canal Iônico/efeitos dos fármacos , Modelos Moleculares , Periplaneta , Canais de Sódio/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
Toxicon ; 40(7): 1041-5, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12076659

RESUMO

Enzymes with gelatinolytic activity were detected in Tityus bahiensis and Tityus serrulatus venom. Their activity was optimal at pH 8.0 in SDS-PAGE-gelatin. They were inhibited by PMSF but not by iodoacetamide, pepstatin or phenantrolin in the assay conditions used. This suggests that these enzymes are serine proteases. The presence of metal ions did not affect the proteolytic activity of these enzymes. Several possible functions may be envisaged for these enzymes: in tissue permeabilization, pancreatitis and toxin processing.


Assuntos
Gelatinases/metabolismo , Venenos de Escorpião/enzimologia , Escorpiões/fisiologia , Animais , Eletroforese em Gel de Poliacrilamida , Gelatinases/análise , Fluoreto de Fenilmetilsulfonil/metabolismo , Inibidores de Proteases/metabolismo , Venenos de Escorpião/química
13.
ISRN Toxicol ; 2012: 673941, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23762636

RESUMO

A new fibrinogenolytic metalloproteinase (Bmoo FIBMP-I) was purified from Bothrops moojeni snake venom. This enzyme was isolated through a combination of three chromatographic steps (ion-exchange, molecular exclusion, and affinity chromatography). Analyses by reverse phase chromatography, followed by mass spectrometry, showed the presence of enzyme isoforms with average molecular mass of 22.8 kDa. The SDS-PAGE analyses showed a single chain of 27.6 kDa, in the presence and absence of reducing agent. The protein has a blocked N-terminal. One of the peptides obtained by enzymatic digestion of a reduced and S-alkylated isoform was completely sequenced by mass spectrometry (MS/MS). Bmoo FIBMP-I showed similarity with hemorrhagic factor and several metalloproteinases (MP). This enzyme degraded Aα-chain faster than the Bß-chain and did not affect the γ-chain of bovine fibrinogen. The absence of proteolytic activity after treatment with EDTA, together with the observed molecular mass, led us to suggest that Bmoo FIBMP-I is a member of the P-I class of the snake venom MP family. Bmoo FIBMP-I showed pH-dependent proteolytic activity on azocasein, but was devoid of coagulant, defibrinating, or hemorrhagic activities. The kinetic parameters of proteolytic activity in azocasein were determined (V max = 0.4596 Uh(-1)nmol(-1) ± 0.1031 and K m = 14.59 mg/mL ± 4.610).

14.
Curr Med Chem ; 18(7): 1019-37, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21254974

RESUMO

Cognitive dysfunction following surgery is a common complication, which increases the incidence of other co-morbid conditions, hospital and health-care costs. The reported rate of the occurrence of post-operative cognitive decline varies with different studies, depending on population profile, type of surgery, definition of cognitive disorder and detection methods, design of study, etc. It remains unclear whether these psychiatric signs and symptoms are direct results of the effects of surgery or general anesthesia. Nonetheless they are more frequent after cardiac surgery and are likely to be multi-factorial, but the patho-mechanisms are not yet fully characterized. This communication provides a synopsis of proteomics tools and delineates novel SELDI-TOF results to evaluate biomarkers in this regard. Presented for the first time is a classification of the clinically relevant forms of post-operative cognitive decline with the advent of a novel subclass.


Assuntos
Líquido Cefalorraquidiano/química , Cognição/fisiologia , Ponte de Artéria Coronária , Análise Serial de Proteínas , Proteoma/análise , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Animais , Humanos , Síndrome
15.
Toxicon ; 56(7): 1172-80, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20417652

RESUMO

In the current study, the putative cDNA for PnTx2-6 toxin of the Phoneutria nigriventer spider venom was cloned and expressed as tioredoxin fusion protein in the cytoplasm of Escherichia coli. The fusion protein was purified from the bacterial extracts by combination of immobilized Ni-ion affinity and gel filtration chromatographies. Then, it was cleaved by enterokinase and the generated recombinant PnTx2-6 (rPnTx2-6) was further purified by reverse-phase HPLC. Likewise the native toxin purified from the spider venom, rPnTx2-6 potentiates the erectile function when injected in rats. This result indicates that the production of functional recombinant PnTx2-6 might be an alternative to provide this basic and valuable tool for study, as well as for further understanding such complex physiological system, including its correlation with the central nervous system and local tissue factors.


Assuntos
Ereção Peniana/efeitos dos fármacos , Peptídeos/farmacologia , Venenos de Aranha/farmacologia , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Escherichia coli/genética , Injeções Subcutâneas , Masculino , Dados de Sequência Molecular , Peptídeos/administração & dosagem , Peptídeos/isolamento & purificação , Priapismo/induzido quimicamente , Ratos , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Venenos de Aranha/administração & dosagem , Venenos de Aranha/isolamento & purificação
16.
Toxicon ; 56(4): 487-96, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20493199

RESUMO

A new vasoactive cytolytic toxin, referred to as Sp-CTx, has been purified from the venom of the scorpionfish Scorpaena plumieri by a combination of gel filtration and anion exchange chromatographies. An estimation of Sp-CTx native molecular mass, performed by size exclusion chromatography, demonstrated that it is a 121 kDa protein. Further physicochemical studies revealed its glycoproteic nature and dimeric constitution, comprising subunits of approximately 65 kDa (MALDI-TOF-MS). Such protein has proved to possess a potent hemolytic activity on washed rabbit erythrocytes (EC(50) 0.46 nM), whose effect was strongly reduced after treatment with antivenom raised against stonefish venom -Synanceja trachynis (SFAV). This cross-reactivity has been confirmed by western blotting. Like S. plumieri whole venom (100 microg/mL), Sp-CTx (1-50 nM) caused a biphasic response on phenylephrine pre-contracted rat aortic rings, characterized by an endothelium- and dose-dependent relaxation phase followed by a contractile phase. The vasorelaxant activity has been abolished by l-NAME, demonstrating the involvement of nitric oxide on the response. We report here the first isolation of a cytolytic/vasoactive protein from scorpionfish venom and the data provided suggest structural and functional similarities between Sp-CTx and previously published stonefish hemolytic toxins.


Assuntos
Citotoxinas/química , Venenos de Peixe/química , Peixes Venenosos , Hemolíticos/química , Vasodilatadores/química , Animais , Aorta/efeitos dos fármacos , Citotoxinas/isolamento & purificação , Citotoxinas/toxicidade , Eritrócitos/efeitos dos fármacos , Venenos de Peixe/isolamento & purificação , Venenos de Peixe/toxicidade , Hemolíticos/isolamento & purificação , Hemolíticos/toxicidade , Técnicas In Vitro , Contração Miocárdica/efeitos dos fármacos , Coelhos , Ratos , Vasodilatadores/isolamento & purificação , Vasodilatadores/toxicidade
18.
J Epidemiol Community Health ; 63(11): 920-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19762456

RESUMO

BACKGROUND: There is a scarcity of studies evaluating the relationship between food costs and adherence to different food patterns and obesity. METHODS: This was a dynamic cohort of Spanish university graduates (n = 17,197 for the cross-sectional baseline assessment and n = 11,195 for the prospective follow-up analyses). Mean age was 38.6 (SD 12.2) years, and 60% of participants were women. A 136-item food frequency questionnaire previously validated in Spain was used. Principal component analysis (PCA) was used to derive dietary patterns. Average cost of food was calculated from official Spanish government data. Self-reported weight was previously validated in the cohort. Body weight was assessed both at baseline and during follow-up. RESULTS: PCA identified two dietary patterns, designated as western and Mediterranean. Participants with the highest scores on the western dietary pattern (fifth quintile vs first quintile) spent less money (-0.64 euro (-$0.80) per 1000 kcal (95% CI -0.68 euro to -0.61 euro, p for trend <0.001)) on their daily food costs, whereas the opposite was true for the Mediterranean dietary pattern (+0.71 euro (+$0.90) (95% CI +0.67 euro to +0.74 euro, p for trend <0.001). After adjusting for dietary pattern scores and other potential confounders, higher daily food costs were significantly associated with greater weight gain. CONCLUSIONS: These data suggest that a Mediterranean dietary pattern is more expensive to follow than a western dietary pattern. This economic barrier should be considered when counselling patients about following a healthy diet because cost may be a prohibitive factor.


Assuntos
Dieta/economia , Abastecimento de Alimentos/economia , Aumento de Peso , Adulto , Custos e Análise de Custo , Estudos Transversais , Dieta/tendências , Inquéritos sobre Dietas , Dieta Mediterrânea/economia , Dieta Mediterrânea/estatística & dados numéricos , Ingestão de Energia , Feminino , Abastecimento de Alimentos/estatística & dados numéricos , Humanos , Masculino , Análise de Regressão , Espanha
19.
Artigo em Inglês | MEDLINE | ID: mdl-17218159

RESUMO

Arachnids have a venom apparatus and secrete a complex chemical mixture of low molecular mass organic molecules, enzymes and polypeptide neurotoxins designed to paralyze or kill their prey. Most of these toxins are specific for membrane voltage-gated sodium channels, although some may also target calcium or potassium channels and other membrane receptors. Scorpions and spiders have provided the greatest number of the neurotoxins studied so far, for which, a good number of primary and 3D structures have been obtained. Structural features, comprising a folding that determines a similar spatial distribution of charged and hydrophobic side chains of specific amino acids, are strikingly common among the toxins from spider and scorpion venoms. Such similarities are, in turn, the key feature to target and bind these proteins to ionic channels. The search for new insecticidal compounds, as well as the study of their modes of action, constitutes a current approach to rationally design novel insecticides. This goal tends to be more relevant if the resistance to the conventional chemical products is considered. A promising alternative seems to be the biotechnological approach using toxin-expressing recombinant baculovirus. Spider and scorpion toxins having insecticidal activity are reviewed here considering their structures, toxicities and action mechanisms in sodium channels of excitable membranes.


Assuntos
Aracnídeos/fisiologia , Proteínas de Insetos/toxicidade , Canais Iônicos/efeitos dos fármacos , Neurotoxinas/toxicidade , Peptídeos/toxicidade , Venenos de Aranha/toxicidade , Animais , Axônios/efeitos dos fármacos , Axônios/fisiologia , Proteínas de Insetos/química , Canais Iônicos/antagonistas & inibidores , Canais Iônicos/metabolismo , Neurotoxinas/química , Peptídeos/química , Controle Biológico de Vetores , Dobramento de Proteína , Escorpiões/fisiologia , Venenos de Aranha/química , Aranhas/fisiologia
20.
Cell Mol Neurobiol ; 27(1): 129-46, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17151945

RESUMO

Various neurotoxins have been described from the venom of the Brazilian spider Phoneutria nigriventer, but little is known about the venoms of the other species of this genus. In the present work, we describe the purification and some structural and pharmacological features of a new toxin (PRTx3-7) from Phoneutria reidyi that causes flaccid paralysis in mice. The observed molecular mass (4627.26 Da) was in accordance with the calculated mass for the amidated form of the amino acid sequence (4627.08 Da). The presence of an alpha-amidated C-terminus was confirmed by MS/MS analysis of the C-terminal peptide, isolated after enzymatic digestion of the native protein with Glu-C endoproteinase. The purified protein was injected (intracerebro-ventricular) into mice at dose levels of 5 microg/mouse causing immediate agitation and clockwise gyration, followed by the gradual development of general flaccid paralysis. PRTx3-7 at 1 microM inhibited by 20% the KCl-induced increase on [Ca2+]i in rat brain synaptosomes. The HEK cells permanently expressing L, N, P/Q and R HVA Ca2+ channels were also used to better characterize the pharmacological features of PRTx3-7. To our surprise, PRTx3-7 shifted the voltage-dependence for activation towards hyperpolarized membrane potentials for L (-4 mV), P/Q (-8 mV) and R (-5 mV) type Ca2+ currents. In addition, the new toxin also affected the steady state of inactivation of L-, N- and P/Q-type Ca2+ currents.


Assuntos
Canais de Cálcio/efeitos dos fármacos , Ativação do Canal Iônico/efeitos dos fármacos , Venenos de Aranha/farmacologia , Sequência de Aminoácidos , Animais , Canais de Cálcio/genética , Canais de Cálcio/fisiologia , Células Cultivadas , Eletrofisiologia , Feminino , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Ratos , Ratos Wistar , Homologia de Sequência de Aminoácidos , Venenos de Aranha/química , Venenos de Aranha/isolamento & purificação , Aranhas , Sinaptossomos/efeitos dos fármacos , Transfecção
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