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1.
Phytother Res ; 37(8): 3424-3437, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37042623

RESUMO

Dyslipidemia is common in patients with chronic kidney disease. Curcumin, a bioactive polyphenol from Curcuma longa, can improve lipid profile. This study aims to analyze the effects of Curcuma Longa extract supplementation on lipid profile and lipoprotein subfractions in hemodialysis (HD) patients. This is a longitudinal, double-blind, washout-period randomized clinical trial. The patients were randomized into two groups: the curcumin group (n = 10) (orange and carrot juice with 2.5 g of Curcuma Longa extract) and the control group (n = 11) (juice without curcumin) 3x/w during HD sessions for 3 months. After the washout period, patients continued the supplementation as a crossover for the same period. The lipid profile was measured using enzymatic assays. The high-density lipoprotein and low-density lipoprotein subfractions analyses were performed using LipoprintTM. In the curcumin group, the triglyceride values tended to decrease with a different triglyceride variation between the pre and post-intervention for the control and curcumin groups of 38.5 (19.8) mg/dL (p = 0.06). There was no statistical difference in the others parameters. In conclusion, Curcuma longa extract may be a good nutritional strategy to reduce triglyceride plasma levels in hemodialysis patients, but it seems ineffective for the other parameter.


Assuntos
Curcuma , Curcumina , Humanos , Curcumina/farmacologia , Extratos Vegetais/farmacologia , Triglicerídeos , Lipoproteínas , Diálise Renal , Suplementos Nutricionais
2.
Crit Rev Food Sci Nutr ; 63(29): 10173-10196, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35593230

RESUMO

Fermentation has been used since the Early Neolithic period to preserve foods. It has inherent organoleptic and nutritive properties that bestow health benefits, including reducing inflammation and oxidative stress, supporting the growth of salutogenic microbiota, enhancing intestinal mucosal protection and promoting beneficial immunometabolic health effects. The fermentation of food with specific microbiota increases the production salutogenic bioactive compounds that can activate Nrf2 mediated cytoprotective responses and mitigate the effects of the 'diseasome of aging' and its associated inflammageing, which presents as a prominent feature of obesity, type-2 diabetes, cardiovascular and chronic kidney disease. This review discusses the importance of fermented food in improving health span, with special reference to cardiometabolic diseases.


Assuntos
Doenças Cardiovasculares , Alimentos Fermentados , Microbiota , Humanos , Dieta , Obesidade/prevenção & controle , Doenças Cardiovasculares/prevenção & controle , Fermentação
3.
EPMA J ; 11(4): 565-579, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33240450

RESUMO

Alkaline phosphatase (AP) is a ubiquitous membrane-bound glycoprotein that catalyzes phosphate monoesters' hydrolysis from organic compounds, an essential process in cell signaling. Four AP isozymes have been described in humans, placental AP, germ cell AP, tissue nonspecific AP, and intestinal AP (IAP). IAP plays a crucial role in gut microbial homeostasis, nutrient uptake, and local and systemic inflammation, and its dysfunction is associated with persistent inflammatory disorders. AP is a strong predictor of mortality in the general population and patients with cardiovascular and chronic kidney disease (CKD). However, little is known about IAP modulation and its possible consequences in CKD, a disease characterized by gut microbiota imbalance and persistent low-grade inflammation. Mitigating inflammation and dysbiosis can prevent cardiovascular complications in patients with CKD, and monitoring factors such as IAP can be useful for predicting those complications. Here, we review IAP's role and the results of nutritional interventions targeting IAP in experimental models to prevent alterations in the gut microbiota, which could be a possible target of predictive, preventive, personalized medicine (PPPM) to avoid CKD complications. Microbiota and some nutrients may activate IAP, which seems to have a beneficial impact on health; however, data on CKD remains scarce.

4.
J Appl Microbiol ; 121(6): 1519-1529, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27566664

RESUMO

AIMS: To investigate the anti-HSV and anti-inflammatory effects of a standardized ethyl acetate extract (SEAE) prepared with the stem bark of Strychnos pseudoquina, along with two isolated compounds: quercetin 3-O-methyl ether (3MQ) and strychnobiflavone (SBF). METHODS AND RESULTS: The mechanisms of action were evaluated by different methodological strategies. SEAE and SBF affected the early stages of viral infection and reduced HSV-1 protein expression. Both flavonoids elicited a concentration-dependent inhibition of monocyte chemoattractant protein-1 (MCP-1), whereas 3MQ reduced the chemokine release more significantly than SBF. Conversely, both compounds stimulated the production of the cytokines TNF-α and IL-1-ß in LPS-stimulated cells, especially at the intermediate and the highest tested concentrations. CONCLUSIONS: SEAE and SBF interfered with various steps of HSV replication cycle, mainly adsorption, postadsorption and penetration, as well as with ß and γ viral proteins expression; moreover, a direct inactivation of viral particles was observed. Besides, both flavonoids inhibited MCP-1 selectively, a feature that may be beneficial for the development of new anti-HSV agents. SIGNIFICANCE AND IMPACT OF THE STUDY: The results indicated that the samples present anti-HSV and anti-inflammatory activities, at different levels, which is an interesting feature since cold and genital sores are accompanied by an inflammation process.


Assuntos
Antivirais/farmacologia , Biflavonoides/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Quercetina/análogos & derivados , Strychnos/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antivirais/química , Biflavonoides/química , Brasil , Linhagem Celular , Quimiocina CCL2/metabolismo , Chlorocebus aethiops , Citocinas/metabolismo , Herpesvirus Humano 1/fisiologia , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Quercetina/química , Quercetina/farmacologia , Células Vero
5.
Arq. bras. med. vet. zootec ; 67(5): 1241-1248, tab
Artigo em Português | LILACS | ID: lil-764450

RESUMO

A piometra é uma afecção comum em cadelas com uma etiologia hormonal associada à infecção bacteriana, levando ao acúmulo de exsudato uterino. Desequilíbrios ácido-base e hidroeletrolíticos são complicações que contribuem para a progressão da doença, o que piora o estado geral da paciente e pode levá-la ao óbito. O objetivo do presente trabalho foi caracterizar os distúrbios ácido-base e eletrolíticos em cadelas com piometra, além de avaliar se a terapia hídrica pré-cirúrgica (Ringer lactato) é efetiva na correção desses desequilíbrios. Vinte cadelas com piometra foram submetidas à hemogasometria em oito tempos preestabelecidos. Concluiu-se que o distúrbio ácido-base mais frequente foi a alcalose respiratória e que a terapia hídrica no pré-cirúrgico com solução Ringer lactato foi efetiva na correção da acidose metabólica e proporcionou melhora na alcalose respiratória, embora não tenha corrigido quadros de alcalose metabólica.


Pyometra is a common disease in dogs with a hormonal etiology associated with a bacterial infection and leading to accumulation of uterine exudates. Acid-base and electrolyte disturbances are complications that contribute to disease progression, worsening the condition of the patient, possibly leading death. The aim of this study was to characterize the acid-base and electrolyte disturbances in dogs with pyometra, and to evaluate whether preoperative fluid therapy (Ringer's lactate) is effective in correcting these imbalances. Twenty bitches with pyometra were subjected to blood gas analysis in eight pre-set times. It was concluded that the acid-base disorder was the most frequent respiratory alkalosis and fluid therapy in the preoperative Ringer 's lactate solution was effective in the correction of metabolic acidosis, although this has not corrected metabolic alkalosis frames and has provided improved alkalosis breathing .


Assuntos
Animais , Cães , Equilíbrio Ácido-Base , Alcalose Respiratória , Piometra/veterinária , Equilíbrio Hidroeletrolítico , Antibacterianos , Cetose/veterinária , Histerectomia/veterinária , Tramadol/uso terapêutico
7.
Oncol Rep ; 32(4): 1419-26, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25050586

RESUMO

Colorectal cancer (CRC) is one of the most frequent cancers worldwide. Adenoma is the main precursor lesion and, recently, the serrated polyps were described as a group of colorectal lesions with malignant potential. The morphologic and biologic characterizations of serrated polyps remain limited. The aim of the present study was to determine the frequency of KRAS and BRAF mutations and microsatellite instability (MSI) in CRC precursor lesions, to evaluate the association between molecular, pathologic and morphologic alterations in precursor lesions and to compare with the alterations detected in CRC. A series of 342 precursor lesions were removed from 155 patients during colonoscopy. After morphologic classification, molecular analysis was performed in 103 precursor lesions, and their genetic profile compared with 47 sporadic CRCs. Adenomas were the main precursor lesions (70.2%). Among the serrated polyps, the main precursor lesion was hyperplastic polyps (HPs) (82.4%), followed by sessile serrated adenomas (12.7%) and traditional serrated adenomas (2.0%). KRAS mutations were detected in 13.6% of the precursor lesions, namely in adenomas and in HPs, but in no serrated adenoma. BRAF mutations were found in 9 (8.7%) precursor lesions, mainly associated with serrated polyps and absent in adenomas (P<0.001). High MSI (MSI-H) was absent in precursor lesions. In the 47 CCR cases, 46.8% exhibited KRAS mutation, 6.5% BRAF mutations and 10.6% MSI-H. This study confirms the role of KRAS and BRAF mutations in CRC carcinogenesis, a crucial step in implementing CRC screening strategies.


Assuntos
Adenocarcinoma/genética , Adenoma/genética , Pólipos do Colo/genética , Neoplasias Colorretais/genética , Instabilidade de Microssatélites , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adenocarcinoma/patologia , Adenoma/patologia , Idoso , Idoso de 80 Anos ou mais , Pólipos do Colo/patologia , Colonoscopia , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas p21(ras)
8.
Parasitology ; 140(3): 396-405, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23137846

RESUMO

The factors that characterize Acanthamoeba strains as harmless or potentially pathogenic have not been elucidated. Analysing the in vitro and in vivo parameters of Acanthamoeba samples, including heat tolerance at temperatures close to that of the human body, cytopathic effects, and their ability to cause infections in animals, has been proposed to identify their pathogenic potential. Another promising criterion for differentiating strains is the analysis of their biochemical and immunochemical properties. In this study, a comparative evaluation between clinical and environmental Acanthamoeba isolates was performed on the basis of physiological, morphological, and immunochemical criteria. Crude antigens were used to characterize the protein profiles by electrophoresis and immunize mice to produce polyclonal and monoclonal antibodies. The antibodies were characterized using ELISA, Western blotting, and immunofluorescence techniques. The results obtained with polyclonal antibodies suggest the presence of specific proteins for each studied isolate and co-reactive immunochemical profiles among conserved components. Ten monoclonal antibody clones were obtained; mAb3 recognized 3 out of 4 samples studied. The results of this study may help standardize criteria for identifying and characterizing Acanthamoeba strains. Taken together, our results support the view that a set of features may help differentiate Acanthamoeba species and isolates.


Assuntos
Ceratite por Acanthamoeba/parasitologia , Acanthamoeba/classificação , Poeira/análise , Parasitologia/métodos , Acanthamoeba/imunologia , Acanthamoeba/isolamento & purificação , Acanthamoeba/ultraestrutura , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Anticorpos Antiprotozoários/biossíntese , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/administração & dosagem , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/isolamento & purificação , Western Blotting , Eletroforese , Ensaio de Imunoadsorção Enzimática/métodos , Características da Família , Imunofluorescência , Humanos , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura , Proteínas de Protozoários/química , Proteínas de Protozoários/imunologia , Especificidade da Espécie
9.
Vaccine ; 29(45): 7992-8001, 2011 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-21872636

RESUMO

The venom of Loxosceles intermedia (Li) spiders is responsible for cutaneous lesions and other clinical manifestations. We previously reported that the monoclonal antibody LimAb7 can neutralize the dermonecrotic activity of crude Li venom. In this study, we observed that this antibody recognizes several proteins from the venom dermonecrotic fraction (DNF), including LiD1. Identifying the epitope of such a neutralizing antibody could help designing immunogens for producing therapeutic sera or vaccination approaches. To this aim, two sets of 25- and 15-mer overlapping peptides that cover the complete amino acid sequence of LiD1 were synthesized using the SPOT technique. None of them was recognized by LimAb7, suggesting that the epitope is discontinuous. Then, the screening of four peptide phage-display libraries yielded four possible epitope mimics that, however, did not show any obvious similarity with the LiD1 sequence. These mimotopes, together with a 3D model of LiD1, were used to predict with the MIMOP bioinformatic tool the putative epitope region (residues C197, Y224, W225, T226, D228, K229, R230, T232 and Y248 of LiD1) recognized by LimAb7. This analysis and the results of alanine-scanning experiments highlighted a few residues (such as W225 and D228) that are found in the active site of different SMases D and that may be important for LiD1 enzymatic activity. Finally, the only mimotope NCNKNDHLFACW that interacts with LimAb7 by SPOT and its analog NSNKNDHLFASW were used as immunogens in rabbits. The resulting antibodies could neutralize some of the biological effects induced by crude Li venom, demonstrating a mimotope-induced protection against L. intermedia venom.


Assuntos
Anticorpos Neutralizantes/sangue , Antitoxinas/sangue , Aracnídeos , Epitopos/imunologia , Venenos de Aranha/antagonistas & inibidores , Vacinas de Subunidades Antigênicas/imunologia , Animais , Mapeamento de Epitopos , Feminino , Biblioteca de Peptídeos , Perciformes , Coelhos , Venenos de Aranha/toxicidade
10.
Arq. neuropsiquiatr ; 69(2b): 387-394, 2011. tab
Artigo em Inglês | LILACS | ID: lil-588103

RESUMO

Persistent pain is a frequent health problem in the elderly. Its prevalence ranges from 45 percent to 80 percent. Chronic diseases, such as depression, cardiovascular disease, cancer and osteoporosis have a higher prevalence in aged individuals and increase the risk of developing chronic pain. The presence of pain is known to be associated with sleep disorders in these patients, as well as functional impairment, decreased sociability and greater use of the health system, with consequent increase in costs. Alzheimer's disease patients seem to have a normal pain discriminative capacity and they may probably have weaker emotional and affective experience of pain when compared to other types of dementia. Many patients have language deficits and thus cannot properly describe its characteristics. In more advanced cases, it becomes even difficult to determine whether pain is present or not. Therefore, the evaluation of these patients should be performed in a systematic way. There are three ways to measure the presence of pain: by direct questioning (self-report), by direct behavioral observation and by interviews with caregivers or informants. In recent years, many pain scales and questionnaires have been published and validated specifically for the elderly population. Some are specific to patients with cognitive decline, allowing pain evaluation to be conducted in a structured and reproducible way. The next step is to determine the type of painful syndrome and discuss the bases of the pharmacological management, the use of multiple medications and the presence of comorbidities demand the use of smaller doses and impose contra-indications against some drug classes. A multiprofessional approach is the rule in the management of these patients.


Dor persistente é um problema de saúde frequente no idoso e sua prevalência varia de 45 a 80 por cento. Doenças crônicas, como depressão, distúrbios cardiovasculares, câncer e osteoporose tem alta prevalência em indivíduos idosos e aumentam o risco de desenvolver dor crônica. Nestes indivíduos, a presença de dor está associada a distúrbios do sono, prejuízo funcional, diminuição da sociabilidade e maior procura dos serviços de saúde, com o consequente aumento dos custos de saúde. Pacientes com Alzheimer têm uma capacidade discriminativa dolorosa normal e uma experiência afetiva e emocional da dor mais atenuada quando comparados com outros tipos de demência. Muitos pacientes têm déficits de linguagem e não podem descrever adequadamente as características de sua dor. Em casos avançados, torna-se difícil determinar se a dor está realmente presente ou não. Desta forma, a avaliação destes doentes deve ser realizada de forma sistemática. Há três formas de se avaliar a dor: questionários diretos, observação direta do comportamento ou entrevistas diretas com os cuidadores ou informantes. Nos últimos anos muitas escalas e questionários para dor foram publicados e validados especificamente para a população idosa. Alguns são específicos para pacientes com declínio cognitivo, permitindo que a evolução da dor possa ser conduzida de uma forma estruturada e reprodutível. O passo seguinte é se determinar o tipo de síndrome dolorosa e se discutir as bases do manejo farmacológico. O uso de múltiplas medicações e a presença de comorbidades exige o uso de pequenas doses e impõem contra-indicações para algumas classes de drogas. A abordagem multidisciplinar é a regra no seguimento a longo prazo destes doentes.


Assuntos
Idoso , Humanos , Doença de Alzheimer/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Medição da Dor/métodos , Dor/fisiopatologia , Doença de Alzheimer/psicologia , Doença Crônica , Transtornos Cognitivos/psicologia , Avaliação Geriátrica , Dor/psicologia
11.
Vaccine ; 28(4): 970-80, 2010 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-19962461

RESUMO

The Amm VIII protein was previously isolated from the venom of the scorpion Androctonus mauretanicus mauretanicus. Despite 87% identity with AaH II, the most toxic alpha-type scorpion toxin, Amm VIII is not toxic to mice. However, antisera against Amm VIII protect mice from AaH II lethal action. Here, we report that the Amm VIII protein elicits antibodies that only recognize discontinuous-type epitopes since we could not observe any antibody binding to overlapping 12-mer peptides covering the whole Amm VIII sequence. By using a new bioinformatic tool, 24 peptides mimicking discontinuous regions of Amm VIII were designed in silico, then prepared by Spot synthesis. Seven of these discontinuous-continuous peptides were recognized by anti-Amm VIII antibodies. Analysis of the 3D location of the segments that compose the antigenically reactive discontinuous-continuous peptides, allowed us to group those antigenic segments into three regions of Amm VIII, putatively corresponding to discontinuous antigenic regions of alpha-type scorpion toxins. Anti-Amm VIII antibodies were also found to cross-react towards several of the discontinuous-continuous peptides designed from the AaH II structure, pointing to a possible involvement of the corresponding discontinuous epitopes in the capacity displayed by anti-Amm VIII antibodies to neutralize AaH II. Altogether, our results show that it is possible to design antibody-reactive peptides from discontinuous parts of scorpion toxins. The position of the reactive segments in the structural context of scorpion toxins highlights the antigenic properties of the Amm VIII anatoxin and concurs to explain the capacity of anti-Amm VIII antibodies to neutralize the potent AaH II toxin.


Assuntos
Antitoxinas/imunologia , Mapeamento de Epitopos , Epitopos/imunologia , Dados de Sequência Molecular , Venenos de Escorpião/imunologia , Escorpiões/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Neutralizantes/imunologia , Reações Cruzadas , Epitopos/genética , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Testes de Neutralização , Estrutura Terciária de Proteína , Coelhos , Venenos de Escorpião/genética , Escorpiões/genética
12.
J Pharm Biomed Anal ; 48(1): 62-9, 2008 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-18572342

RESUMO

A need for more reliable and faster analytical methods for the identification of the active pharmaceutical ingredient (API) in finished pharmaceutical products is launched by the International Conference on Harmonisation (ICH) of Technical Requirements for Registration of Pharmaceuticals for Human Use, Test Procedures and Acceptance Criteria for New Drug Substances and New Drug Products: Chemical Substances, Q6A (1999). The use of infrared spectroscopy is suggested as a means to obtain specific identification. Near-infrared spectroscopy (NIRS) is a reliable method that offers important advantages for the large-scale production of tablets, such as high-throughput and accurate multiparametric data collection. Despite the grown number of reported NIRS identification methods, only a few methods have been approved by the regulatory authorities, which might be due to difficulties on clearly presenting the methods in official documents and audits. Motivated by the lack of clear protocols for the NIRS method's development, here we propose a process for building reliable identification NIRS methods. For illustration purposes, a method is described for the identification of API in coated tablets containing 2%, 4% and 8% of thiamazole. The method described was successfully validated according to the International Conference on Harmonisation (ICH) of Technical Requirement for Registration of Pharmaceuticals for Human Use, Validation of Analytical Procedures: Text and Methodology, Q2 (2005). The described method was subsequently approved by European national authorities and thus is suitable for use in cGMP environment.


Assuntos
Composição de Medicamentos/métodos , Preparações Farmacêuticas/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Comprimidos com Revestimento Entérico/análise , Tecnologia Farmacêutica/métodos , Química Farmacêutica/métodos , Guias como Assunto , Preparações Farmacêuticas/química , Controle de Qualidade , Comprimidos com Revestimento Entérico/química
14.
Toxicon ; 46(6): 664-71, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16168449

RESUMO

Monoclonal antibodies (mAbs) against Tityus serrulatus venom were obtained by the fusion of SP2/0 murine myeloma cells and spleen cells from BALB/c mice immunized with a toxic fraction (TstFG50) of the Tityus venom (this G50 chromatography fraction represents most of the toxicity of the crude venom) conjugated to bovine serum albumin (BSA) with glutaraldehyde. From the initial screening of over 200 hybridoma fusion wells, a panel of 9 anti-TstFG50 secreting hybridomas was established. The capacity of mAbs to neutralize the TstFG50 toxic fraction toxic was determined by in vitro neutralization assays and by inhibition of the binding of 125I-TsVII to its site on rat brain synaptosomes. Only mAbTs1 neutralized 50% of the toxic effects produced by scorpion venom and showed 35% inhibition of the binding of 125I-TsVII at 10(-7) M. To map the epitope recognized by the protective mAbTs1, we prepared a comprehensive series of overlapping 15-mer synthetic peptides covering the amino acid sequences of the four Tityus proteins. MAbTs1 reacted with peptide 26 of TsIV (KKSKDKKADSGYSYW), peptide 30 of TsVII (KKGSSGYSAWPASYS) and peptide 31 of TsNTxP (KKGSSGYSAWPASYS). MAbTs1 was not reactive with any peptide from TsII. The N-terminal lysine residue from the epitope was found to be critical for mAbTs1 binding. The epitope was positioned on the available three-dimensional structure of TsVII together with the recently identified residues from the pharmacophore of beta-scorpion toxins. The neutralizing properties of mAbTs1 might be explained by spatial vicinity of epitope residues with pharmacophore residues.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Hibridomas/metabolismo , Modelos Moleculares , Venenos de Escorpião/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/metabolismo , Encéfalo/citologia , Linhagem Celular Tumoral , Fracionamento Químico , Ensaio de Imunoadsorção Enzimática , Epitopos/genética , Glutaral , Hibridomas/química , Camundongos , Dados de Sequência Molecular , Testes de Neutralização , Venenos de Escorpião/genética , Venenos de Escorpião/metabolismo , Soroalbumina Bovina , Baço/citologia , Sinaptossomos/metabolismo
15.
Toxicon ; 46(2): 210-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15970301

RESUMO

Overlapping pentadecapeptides covering the complete amino acid sequence of TsII, TsVII and TsIV toxins from the venom of scorpion Tityus serrulatus (Ts), were prepared by use of the Spot method of multiple peptide synthesis. Horse anti-Ts antisera for therapeutic use were tested for their binding to peptides. All nine antisera tested showed reactivity with several peptides from the three toxins. Three antigenic regions, one in the very N-terminal, the second in the central part and the other in the C-terminal part of the three toxins were frequently, but not constantly recognized, with an intensity that seemed to be related to the neutralizing potency of the tested antivenom. Thus the corresponding peptides (residues 1-15 and 48-62 of TsII; residues 1-15, 16-30 and 48-62 of TsIV and residues 1-15 and 47-61 of TsVII) were synthesized, coupled to KLH and used as antigens to coat the microtitration plates to determine any relationship between their ELISA reactivity with therapeutic horse antivenoms and the neutralizing potential of these antivenoms. The mixture of the N-terminal peptide of TsII, of the N-terminal TsVII peptide and of the C-terminal of TsIV was found to give a linear relationship with the neutralizing titer of horse serum of low neutralizing potency (< or =1 mg/ml). However, high neutralizing antivenoms did not show the expected response in peptide ELISA. This observation is discussed in the context of the occurrence of continuous and discontinuous epitopes on toxins.


Assuntos
Epitopos/genética , Soros Imunes/imunologia , Soros Imunes/metabolismo , Peptídeos/metabolismo , Venenos de Escorpião/genética , Escorpiões/química , Sequência de Aminoácidos , Animais , Ensaio de Imunoadsorção Enzimática , Cavalos/sangue , Soros Imunes/genética , Imunoensaio , Dados de Sequência Molecular , Testes de Neutralização , Peptídeos/genética , Venenos de Escorpião/imunologia , Escorpiões/genética
17.
Toxicon ; 44(3): 233-41, 2004 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-15302529

RESUMO

The possibility of raising a humoral immune response capable of inducing in vivo protection against the lethal effects of Tityus serrulatus (Ts) scorpion venom was evaluated in the mouse model. An immunogen was prepared that consists of a toxic fraction (TstFG(50)) of the Tityus venom (this G(50) chromatography fraction represents most of the toxicity of the crude venom) conjugated to bovine serum albumin (BSA) with glutaraldehyde. TstFG(50) coupled to BSA yielded a thoroughly detoxified immunogen. BALB/c and C57BL/10 mice were immunized with this preparation and all developed an antibody response. In vivo protection assays one week after the last immunization showed that vaccinated mice could resist the challenge by twice the LD(50) of the TstFG(50), a dose which killed all control non-immune mice. The protective effect persisted nine weeks after the end of the immunization protocol. To characterize epitopes of protective antibodies we used the Spot method of multiple peptide synthesis to prepare sets of immobilized 15 mer overlapping peptides, covering the complete amino acid sequences of the main Tityus toxins, TsII and TsVII (both beta-type toxins) and TsIV, an alpha-type toxin that is the major lethal component of the venom. Antibody binding to peptides, revealed one major antigenic region in the C-terminal part of the three toxins and another region in the helical part of TsII and TsIV toxins. It is likely that these epitopes correspond to neutralizing epitopes since they correspond to regions of the toxins that are known to be involved in the active site of the toxins.


Assuntos
Anticorpos/genética , Formação de Anticorpos/imunologia , Imunização , Camundongos/imunologia , Venenos de Escorpião/imunologia , Escorpiões/metabolismo , Sequência de Aminoácidos , Animais , Ensaio de Imunoadsorção Enzimática , Epitopos/genética , Glutaral/metabolismo , Imunoensaio , Dose Letal Mediana , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Modelos Moleculares , Dados de Sequência Molecular , Venenos de Escorpião/metabolismo , Venenos de Escorpião/toxicidade , Alinhamento de Sequência , Soroalbumina Bovina/metabolismo , Testes de Toxicidade Aguda , Vacinas Sintéticas/imunologia
18.
Cornea ; 23(2): 136-42, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15075882

RESUMO

OBJECTIVE: To study the aerobic conjunctival flora of diabetic patients and its relation to the presence and level of diabetic retinopathy and the duration of the disease. METHODS: One hundred three patients from the diabetic retinopathy screening program of the Federal University of São Paulo with no evidence of ocular surface disease were included. The diabetic patient cohort was compared with 60 nondiabetic subjects. All patients underwent slit-lamp evaluation, conjunctival scrapings, and indirect ophthalmoscopy. RESULTS: The frequency of positive conjunctival cultures was significantly higher in the diabetic group (94.18%) than in the nondiabetic group (73.33%). Among diabetic patients, a significantly higher frequency of positive cultures was detected in those with diabetic retinopathy than in those without retinopathy. Neither the duration of the diabetes nor the hypoglycemic therapy correlated with the culture results. Coagulase-negative Staphylococcus was the most common microorganism isolated, and its identification was more frequent in patients with retinopathy than in those without diabetic retinopathy. CONCLUSION: Diabetic patients have a significantly higher number of positive conjunctival cultures. The presence of diabetic retinopathy was correlated with an increase in positive cultures and a higher proportion of coagulase-negative Staphylococcus.


Assuntos
Bactérias Aeróbias/isolamento & purificação , Túnica Conjuntiva/microbiologia , Diabetes Mellitus/microbiologia , Retinopatia Diabética/microbiologia , Idoso , Técnicas Bacteriológicas , Feminino , Humanos , Masculino , Oftalmoscopia
19.
Toxicon ; 40(1): 89-95, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11602284

RESUMO

We have used the Spot method of multiple peptide synthesis to prepare sets of immobilized overlapping peptides of uniform size (15 mer), covering the complete amino acid sequences of TsNTxP a non-toxic and immunogenic protein and TsIV, an alpha-type toxin that is the major lethal component of the venom of scorpion Tityus serrulatus. Anti-TsNTxP antibodies binding to peptides, revealed three antigenic regions, one in the N-terminal, the second in the central part and the other in the C-terminal part of TsNTxP. One peptide epitope in the C-terminal part of TsIV was identified with anti-TsIV neutralizing rabbit antibodies. Anti-peptide antibodies were raised against these four peptides all together covalently coupled to keyhole limpet hemocyanin (KLH) and found to neutralize in vitro the toxic effects of the T. serrulatus venom. Quantities of venom equivalent to 13.5 LD(50) were effectively neutralized by 1ml of the anti-peptide serum. The antigenic specificities of the anti-peptides were compared by an indirect enzyme-linked immunosorbent assay (ELISA) using synthetic peptides and crude venoms from T. serrulatus, T. bahiensis, T. cambridgei, T. stigmurus, Androctonus autralis Hector and Centruroides sculpturatus to coat the microtitration plates. The anti-peptide antibodies had a comparable high reactivity with the crude venom of T. serrulatus, moderate binding to T. bahiensis, T. cambridgei, T. stigmurus and Centruroides sculpturatus venoms but were unable to recognize the venom of Androctonus autralis Hector. These results show that by using peptides derived from the sequence of scorpion toxins, the generation of anti-peptide antibodies able to neutralize the cognate venom appears to be an alternative strategy for the easy preparation of antivenoms.


Assuntos
Venenos de Escorpião/imunologia , Escorpiões , Vacinação , Sequência de Aminoácidos , Animais , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Epitopos/imunologia , Feminino , Dose Letal Mediana , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Testes de Neutralização , Peptídeos/síntese química , Peptídeos/imunologia , Coelhos , Venenos de Escorpião/farmacologia
20.
Toxicon ; 39(6): 909-11, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11137553

RESUMO

Enzyme linked immunosorbent assays (ELISA) were developed to detect antigens from Phoneutria nigriventer spider venom. Horse anti-P. nigriventer immunoglobulins were prepared by immunoaffinity chromatography and used to set up a sandwich-type ELISA. The specificity of the assay was demonstrated by its capacity to correctly discriminate between the circulating antigens in mice that were experimentally inoculated with P. nigriventer venom from those in mice inoculated with Lycosa sp. and Loxosceles intermedia spider venoms, Tityus serrulatus scorpion venom and Apis mellifera bee venom. Measurable absorbance signals were obtained with 0.8ng of venom per assay. The ELISA was used to follow the kinetic distribution of antigens in experimentally envenomed mice and to detect antigens in the sera of patients envenomed by P. nigriventer.


Assuntos
Antígenos/análise , Ensaio de Imunoadsorção Enzimática/métodos , Venenos de Aranha/imunologia , Animais , Antígenos/imunologia , Reações Cruzadas , Humanos , Camundongos , Sensibilidade e Especificidade
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