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1.
Genes Immun ; 17(1): 13-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26492519

RESUMO

Type 1 diabetes (T1D) is a multifactorial disease that has a strong genetic component. The HLA-G is a nonclassical HLA class I locus that is associated with immunomodulatory functions, including downregulation of innate and adaptive immune responses and induction of immune tolerance. However, there is currently limited information about the involvement of HLA-G in T1D susceptibility. This case-control study aims to investigate the T1D susceptibility association of alleles and genotypes of a widely investigated 14-bp insertion/deletion polymorphism in the HLA-G and to provide further evidence of the frequency distribution of class II HLA-DR-DQ-risk genotypes in T1D children and adolescents in the Brazilian population. The deletion allele and the homozygous deletion genotype are associated with susceptibility to T1D and the insertion allele and the heterozygous deletion/insertion genotype are associated with protection from T1D. We also confirm that genetic susceptibility to T1D is associated with the DRB1*03:01-DQA1*05:01-DQB1*02:01 and DRB1*04-DQA1*03:01-DQB1*03:02 haplotypes in Brazilian northeast region. The DR3-DQ2/DR4-DQ8 genotype conferred the highest detected risk for T1D. Our results identify a novel association of the 14-bp deletion allele and the homozygous deletion genotype with T1D development and provide additional evidence of the importance of HLA class II heterozygous DR3-DQ2/DR4-DQ8 genotype in T1D susceptibility.


Assuntos
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Predisposição Genética para Doença , Antígenos HLA-G/genética , Adolescente , Brasil , Estudos de Casos e Controles , Criança , Feminino , Antígenos HLA-D/genética , Antígenos HLA-D/imunologia , Antígenos HLA-G/imunologia , Haplótipos , Humanos , Masculino , Polimorfismo Genético
2.
Genet Mol Res ; 15(1)2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26909976

RESUMO

Most epidemiologic studies on bovine leptospirosis are based on serological tests that use antibodies against several serotypes, including the serovar Hardjo, which is widespread and considered to be the most adapted to bovine hosts. However, using only serological studies is not sufficient to identify and distinguish species of leptospires. The aim of this study was report the first isolation in Brazil of two strains serovar Hardjo obtained in urine samples from naturally infected cows in a small Brazilian dairy herd and find the genetic species and consequently the type strain Hardjobovis by molecular characterization. Fifteen dairy cows with a history of reproductive failure, such as abortion and infertility, were selected. Urine samples obtained from each animal were immediately seeded in tubes containing Ellinghausen-McCullough-Johnson-Harris culture medium. The identification of the isolates was performed by Multilocus variable-number tandem-repeat analysis (MLVA) technique and phylogenetic analysis of partial sequence of gene sec Y. From the 15 urine samples evaluated, two Leptospira were found and identified as the Londrina 49 and Londrina 54 strains. The MLVA profiles and sequencing of gene sec Y characterized the isolates as L. borgpetersenii serovar Hardjo strain Hadjobovis because it has different genetic pattern of Leptospira interrogans serovar Hardjo strain Hardjoprajitno. Therefore, more studies are needed including isolation and molecular characterization from regional strains to obtain a better knowledge about epidemiology of serovar Hardjo in bovine which may assist in future strategies of prevention and control of bovine leptospirosis.


Assuntos
Anticorpos Antibacterianos/urina , Doenças dos Bovinos/microbiologia , Genes Bacterianos , Infertilidade Feminina/microbiologia , Leptospira/genética , Leptospirose/microbiologia , Leptospirose/veterinária , Animais , Técnicas de Tipagem Bacteriana , Brasil , Bovinos , Doenças dos Bovinos/patologia , Doenças dos Bovinos/urina , Feminino , Infertilidade Feminina/patologia , Infertilidade Feminina/urina , Leptospira/classificação , Leptospira/isolamento & purificação , Leptospirose/patologia , Leptospirose/urina , Tipagem de Sequências Multilocus , Filogenia , Análise de Sequência de DNA , Sorogrupo
3.
Genet Mol Res ; 13(4): 9828-45, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25501192

RESUMO

Morphological characterization is the most accessible and used method to quantify the genetic diversity of the available germplasm. The multivariate statistical method is highly important for this purpose. This study aimed to characterize parents and hybrids of Passiflora according to morphoagronomic descriptors and estimate the genetic divergence between them based on the joint analysis of qualitative and quantitative variables using the Ward-modified location model (MLM) procedure. One hundred and thirty-eight individuals were assessed (10 P. edulis, 10 P. setacea, and 118 interspecific hybrids) using 23 quantitative and 12 qualitative descriptors. The values for the quantitative descriptors were measured and subjected to multivariate statistics using the Ward-MLM strategy. Large genetic variability was detected by the morphoagronomic data in the 138 genotypes that were evaluated, and the hybrids presented higher variability than the parents. Pseudo-F and pseudo-t2 criteria showed that the optimal number of groups was three. Group I was composed of 118 hybrid genotypes; group II was composed of the 10 P. setacea genotypes, and group III was composed of the 10 P. edulis genotypes. The longest distance was found between groups II and III (474.96). The shortest distance was detected between groups I and II (198.78), which indicates that the segregating population is genetically closer to P. setacea than to P. edulis. The Ward-MLM procedure is a useful tool to detect genetic diversity and group accessions using both qualitative and quantitative variables.


Assuntos
Hibridização Genética , Passiflora/anatomia & histologia , Passiflora/genética , Cruzamentos Genéticos , Flores/anatomia & histologia , Flores/genética , Frutas/anatomia & histologia , Frutas/genética , Genótipo , Funções Verossimilhança , Análise Multivariada , Fenótipo , Característica Quantitativa Herdável , Especificidade da Espécie
4.
Parasitol Res ; 110(5): 1873-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22205347

RESUMO

Freshwater snails of the genus Biomphalaria play a major role as intermediate hosts of Schistosoma mansoni, the etiologic agent of schistosomiasis. While Biomphalaria spp. control by molluscicides is one of the main strategies to reduce the snail population in infected areas, there are few effective molluscicides commercially available. Natural products may be considered as potentially useful and safe molluscicides. We have evaluated the molluscicidal activity of 12 extracts from ten marine organisms on adult and embryonic stages of Biomphalaria glabrata. Only extracts of the red algae Liagora farinosa and of the sponge Amphimedon viridis presented molluscicidal activity. Lethal concentration (LC)(50) values obtained were 120 µg/mL for L. farinosa CH(2)Cl(2) extract (apolar fraction) and 20 µg/mL for A. viridis extract and halitoxin. The polar alga fraction and halitoxin had no effect on B. glabrata embryos. The algae apolar fraction was active on B. glabrata in all embryonic development stages, with LC(50) values for blastulae at 42 µg/mL, gastrulae at 124 µg/mL, trochophore at 180 µg/mL, and veliger at 222 µg/mL. This is the first report of extracts from marine organisms which presented molluscicidal activity.


Assuntos
Organismos Aquáticos/química , Biomphalaria/efeitos dos fármacos , Moluscocidas/isolamento & purificação , Moluscocidas/farmacologia , Poríferos/química , Rodófitas/química , Animais , Análise de Sobrevida
5.
Genet Mol Res ; 10(4): 2457-71, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-22009858

RESUMO

We estimated genetic parameters through multivariate analysis of two species of Passiflora and their hybrids, considered of ornamental potential, based on the morphological characteristics: flower diameter, corona diameter, corona filament size, flower peduncle length, petal length and width, sepal length and width, internode length, stem diameter, leaf length, leaf width (mm), and leaf area (cm(2)). Five specimens of Passiflora sublanceolata [ex P. palmeri var. sublanceolata], five of P. foetida var. foetida and 20 F(1) hybrids between the two were evaluated. A randomized block design with four replications was used. The data were submitted to variance analysis and multivariate procedures, principal components analysis and unweighted pair group method with arithmetic mean grouping. We found significant differences between genotypes for all these morphological parameters. The hybrid plants had the highest variability, making them the most indicated for future improvement programs. The various multivariate techniques gave similar results, allowing separation of the plants into three distinct groups, these being the two paternal species and the hybrids. The hybrids were closer to the male genitors, revealing a paternal effect on the inheritance of vegetative and floral characters. Based on estimates of genetic parameters, the floral characteristics are the most indicated for the selection of plants for ornamental purposes, since these characteristics displayed greatest variability, a variation index of more than one, and high genotypic determination coefficients.


Assuntos
Quimera/genética , Flores/genética , Genótipo , Passiflora/genética , Folhas de Planta/genética , Caules de Planta/genética , Análise Multivariada , Especificidade da Espécie
6.
Br J Dermatol ; 163(4): 769-75, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20560954

RESUMO

BACKGROUND: The nonclassical human leucocyte antigen (HLA)-G molecule has been well recognized as a tolerogenic molecule and few studies have evaluated the role of the molecule in inflammatory cutaneous autoimmune diseases. OBJECTIVES: To evaluate the expression of HLA-G in skin specimens of patients with psoriasis and to analyse its correlation with epidemiological and clinical variables. METHODS: Thirty untreated patients with psoriasis and 32 healthy individuals were enrolled. Immunohistochemistry was applied to identify HLA-G expression in formalin-fixed paraffin-embedded cutaneous skin biopsies. RESULTS: Soluble and membrane-bound HLA-G expression was detected in 30 (90%) of the skin specimens from patients presenting clinical and histopathological features of psoriasis. Although infiltrating lymphomononuclear cells of the dermis exhibited HLA-G expression, the epidermis was primarily targeted. HLA-G expression was also observed in 27% (three of 11) of the specimens that exhibited no clinical and histopathological features of psoriasis (nonaffected areas). In contrast, skin specimens obtained from healthy individuals exhibited no HLA-G expression (P < 0·0001). The intensity of HLA-G expression was not associated with type I/II psoriasis, Psoriasis Area and Severity Index score or clinical forms. CONCLUSIONS: As the HLA-G molecule was consistently expressed in affected and, to a lesser extent, in nonaffected areas of untreated patients with psoriasis, irrespective of the severity of the clinical variants, one may hypothesize that the presence of HLA-G may be responsible, at least in part, for the regulation of autoimmune effector cells.


Assuntos
Antígenos HLA/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Psoríase/imunologia , Pele/imunologia , Adolescente , Adulto , Idoso , Epiderme/imunologia , Feminino , Antígenos HLA-G , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Adulto Jovem
7.
Braz J Biol ; 79(1): 53-62, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29590251

RESUMO

In this study, the activities of antioxidant enzymes, photosynthetic pigments, proline and carbohydrate contents in Pitcairnia encholirioides under ex vitro conditions of water deficit were evaluated. Results show that plants under progressive water stress, previously in vitro cultured in media supplemented with 30 g L-1 sucrose and GA3, accumulated more proline and increased peroxidase (POD) activity and the contents of photosynthetic pigments and carbohydrates. For plants previously in vitro cultured with 15 g L-1 sucrose and NAA, no differences were found for proline content and there were reductions in activities of peroxidase (POD), catalase (CAT) and poliphenoloxidase (PPO), and in contents of carbohydrates, with progress of ex vitro water deficit. After rehydration, plants showed physiological recovery, with enzymatic activities and contents of metabolites similar to those found in the controls not submitted to dehydration, regardless of the previous in vitro culture conditions. These results show that micropropagated P. encholirioides has high tolerance to dehydration once in ex vitro conditions, which can ensure the survival of plants from tissue culture when transferred to its natural environment, emphasizing the importance of such biotechnology for the propagation of endangered species.


Assuntos
Antioxidantes/metabolismo , Bromeliaceae/fisiologia , Secas , Fotossíntese/fisiologia , Prolina/metabolismo , Água/metabolismo , Bromeliaceae/enzimologia , Metabolismo dos Carboidratos , Longevidade , Pigmentos Biológicos , Proteínas de Plantas/metabolismo
8.
RSC Adv ; 8(11): 6136-6145, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35539592

RESUMO

A simple and straightforward method using microwave-assisted reactions is presented for the functionalization of graphene oxide with aromatic and non-aromatic amines, notedly dibenzylamine (DBA), p-phenylenediamine (PPD), diisopropylamine (DPA) and piperidine (PA). The as-synthesized amine-functionalized graphene oxide materials (amine-GO) were characterized using spectroscopic techniques including XRD, FTIR, 13C NMR, XPS, TEM for imaging and thermogravimetric analysis (TGA). The characterization confirmed the functionalization for all amines, reaching relatively high surface nitrogen atomic concentrations of up to 8.8%. The investigations of electrochemical behavior for the amine-GOs show the significant improvement in GO's electrochemical properties through amine functionalization, exhibiting long life cycle stability and reaching specific capacitance values of up to 290 F g-1 and 260 F g-1 for GO-PA and GO-DPA samples, respectively, confirming their potential application as alternative supporting materials in supercapacitors.

9.
Chemosphere ; 182: 339-347, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28505575

RESUMO

In this study, cobalt (Co) was recycled from spent lithium ion batteries (LIBs) and used to synthesize cobalt ferrite (CoFe2O4-LIBs), which was applied as a catalyst for heterogeneous photo Fenton reactions that discolored methylene blue (MB) dye. The co-precipitation method was used to synthesize CoFe2O4-LIBs and CoFe2O4-R nanoparticles with spinel structures using as raw materials of the LIB cathodes and commercial reagents. X-ray diffraction (XRD) identified the formation of spinel-type CoFe2O4, which formed clusters that could be seen under scanning electron microscopy (SEM) analysis and nanometric particles seen under transmission electron microscopy (TEM). Inductively Coupled Plasma Optical Emission Spectrometer (ICP OES) analysis was used to determine the concentrations of metals present in the ferrite, which reached 6.5% (w/w) of Co. The optimal conditions for discoloring the dye were evaluated using a factorial design. Using CoFe2O4 as a catalyst, the best conditions for catalytic reaction were pH 3, 30.0 mg of catalyst, and 8.0 mL of H2O2 73% (v/v). Discoloration efficiencies of 87.3% and 87.7% were obtained from CoFe2O4-R and CoFe2O4-LIBs, respectively. Therefore, CoFe2O4-LIBs proved to be an efficient catalyst for discoloring MB dye using heterogeneous photo-Fenton reactions. This work is of scientific, social, economic, and environmental interest. It investigates the process of synthesizing,characterizing CoFe2O4LIBs and the efficiency of degrading MB dye, subjects that have economic and environmental, and therefore, social interest. The work has scientific interest particularly because of the correlation between the structure of the recycled material and its catalytic properties.


Assuntos
Catálise , Fontes de Energia Elétrica , Compostos Férricos/síntese química , Lítio , Nanoestruturas/química , Cobalto/química , Compostos Férricos/química , Peróxido de Hidrogênio/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Reciclagem/métodos , Difração de Raios X
10.
J Magn Reson ; 175(2): 226-34, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15921938

RESUMO

This article presents the realization of many self-reversible quantum logic gates using two-qubit quadrupolar spin 3/2 systems. Such operations are theoretically described using propagation matrices for the RF pulses that include the effect of the quadrupolar evolution during the pulses. Experimental demonstrations are performed using a generalized form of the recently developed method for quantum state tomography in spin 3/2 systems. By doing so, the possibility of controlling relative phases of superimposed pseudo-pure states is demonstrated. In addition, many aspects of the effect of the quadrupolar evolution, occurring during the RF pulses, on the quantum operations performance are discussed. Most of the procedures presented can be easily adapted to describe selective pulses of higher spin systems (>3/2) and for spin 1/2 under J couplings.

11.
Environ Sci Pollut Res Int ; 22(23): 18987-93, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26233737

RESUMO

Energetic characterization of biomass allows for assessing its energy potential for application in different conversion processes into energy. The objective of this study is to physicochemically characterize pineapple crown leaves (PC) for their application in energy conversion processes. PC was characterized according to ASTM E871-82, E1755-01, and E873-82 for determination of moisture, ash, and volatile matter, respectively; the fixed carbon was calculated by difference. Higher heating value was determined by ASTM E711-87 and ash chemical composition was determined by XRF. The thermogravimetric and FTIR analyses were performed to evaluate the thermal decomposition and identify the main functional groups of biomass. PC has potential for application in thermochemical processes, showing high volatile matter (89.5%), bulk density (420.8 kg/m(3)), and higher heating value (18.9 MJ/kg). The results show its energy potential justifying application of this agricultural waste into energy conversion processes, implementing sustainability in the production, and reducing the environmental liabilities caused by its disposal.


Assuntos
Ananas/química , Biomassa , Energia Renovável , Agricultura , Carbono/análise , Folhas de Planta/química
12.
Toxicon ; 24(8): 751-5, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2877513

RESUMO

Caissarone (mol. wt 229.5; melting point 285-290 degrees C) is a novel purine isolated and purified from the sea-anemone Bunodosoma caissarum. The purine inhibits the detachment of the vitelline layer from the sea-urchin egg plasma membrane after fertilization and this effect leads to polyspermy. Various abnormalities were detected at various embryonic stages, from multipolar egg division through unequal cleavages and exogastrulation up to teratogenic effects on the sea-urchin larvae (echinopluteus).


Assuntos
Venenos de Cnidários/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Purinonas/farmacologia , Animais , Anêmonas-do-Mar , Ouriços-do-Mar , Membrana Vitelina/efeitos dos fármacos
13.
Toxicon ; 28(9): 1029-37, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1979696

RESUMO

The effects of caissarone (C8H11N5O) on guinea-pig ileum and rat duodenum preparations are reported. Caissarone evoked, at first, a small response, as compared with that of applied acetylcholine. This effect was blocked by atropine, hexamethonium and slightly reduced by tetrodotoxin. The main caissarone effect seems to be on the myenteric plexus as it increased spontaneous activity, tone and peristalsis; these effects being counteracted by tetrodotoxin, hexamethonium and atropine. Extracellular electrophysiological recording of the action potentials of myenteric plexus neurons showed an increase in frequency in the presence of caissarone. Caissarone potentiated the longitudinal muscle tension responses elicited by transmural electric stimulation in both control conditions, and when tension was reduced by pretreatment with tetrodotoxin or adenosine triphosphate. Caissarone also potentiated the longitudinal muscle tension responses to applied acetylcholine and this effect was reduced, but not abolished, by tetrodotoxin. Caissarone may have an indirect excitatory action on nicotinic receptors at the ganglia or may act as a reversible antagonist of purine transmitters released by neurons of the myenteric plexus involved in the physiological inhibition of intestinal motility.


Assuntos
Venenos de Cnidários/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Purinonas/farmacologia , Acetilcolina/farmacologia , Animais , Relação Dose-Resposta a Droga , Estimulação Elétrica , Cobaias , Masculino , Ratos , Ratos Endogâmicos
14.
Toxicon ; 31(7): 853-64, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8105563

RESUMO

Peptide neurotoxins were isolated from the venom obtained by electrical stimulation of the sea anemone Bunodosoma caissarum. This technique allows almost pure venom to be collected, and the animals to survive. Three neurotoxins (assayed on crustacean nerves) were isolated by gel filtration and reversed-phase high performance liquid chromatography. Hemolysins were also detected in the venom. The amino acid sequence of a major neurotoxin BcIII was determined. BcIII has 48 amino acid residues with six half-cystine residues. This sequence has homology with the type 1 long sea anemone neurotoxins. Two minor toxins (BcI and II) have similar amino acid composition and amino-terminal sequences to BcIII.


Assuntos
Venenos de Cnidários/isolamento & purificação , Neurotoxinas/isolamento & purificação , Peptídeos/isolamento & purificação , Anêmonas-do-Mar/química , Potenciais de Ação , Sequência de Aminoácidos , Animais , Braquiúros , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Venenos de Cnidários/química , Venenos de Cnidários/toxicidade , Estimulação Elétrica , Técnicas In Vitro , Dados de Sequência Molecular , Neurônios Aferentes/efeitos dos fármacos , Neurotoxinas/química , Neurotoxinas/toxicidade , Peptídeos/química , Peptídeos/toxicidade , Homologia de Sequência de Aminoácidos
15.
Toxicon ; 33(2): 201-8, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7597723

RESUMO

During agonistic interactions intertidal crabs, when exposed to air, produce a foam made of digestive secretions, sea water and air bubbles. They also may release their digestive secretions in water when disturbed. Crabs belonging to the families Majidae, Xanthidae and Portunidae from Atlantic and Pacific areas, not related with human poisoning, possess substances in their digestive secretion which are neurotoxic to mice, block action potentials in nerve preparations, and are reversible on washing. After purification in Bio-gel P-2 chromatography and HPLC analysis, the spontaneously regurgitated secretion, the digestive secretion collected by stomach cannulation of crabs, and the water aquarium replete of intertidal crabs kept overnight show the presence of guanidine neurotoxins.


Assuntos
Digestão/fisiologia , Guanidinas/análise , Neurotoxinas/biossíntese , Neurotoxinas/química , Animais , Braquiúros/química , Cromatografia/métodos , Cromatografia Líquida de Alta Pressão , Sistema Digestório/química , Sistema Digestório/metabolismo , Guanidina , Masculino , Camundongos , Camundongos Endogâmicos , Toxicologia/métodos
16.
Toxicon ; 33(7): 859-61, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8588210

RESUMO

This is an individual case report on envenoming caused by the cnidarian Portuguese man-of-war. The reported local reactions and the clinical symptoms are similar to those already known for Portuguese man-of-war envenoming. As far as we know it is the first clinical case documented for the Brazilian shores.


Assuntos
Mordeduras e Picadas/etiologia , Venenos de Cnidários/intoxicação , Adulto , Mordeduras e Picadas/patologia , Brasil , Humanos , Masculino
17.
Toxicon ; 35(1): 57-65, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9028009

RESUMO

Puffer fish (Tetraodontidae and Diodontidae) possess paralysing toxins (tetrodotoxin and analogues) that are secreted upon stimulation. In a previous work it was demonstrated that mucous secretion from the puffer fish Sphoeroides spengleri, when mixed in sea water passing through the orobranchial cavity of groupers, induced cardiorespiratory alterations. In the present study, skin secretions from Ciclichthys spinosus, S. spengleri and Diodon hystrix were tested on crustacean nerves, sea urchin eggs and mouse erythrocyte suspensions to verify neurotoxic and cytotoxic activities. Ciclichthys spinosus and D. hystrix secretions induced transient depolarizations with 0.16 mg and blocked crustacean nerve conduction after prolonged exposure. Both secretions had cytotoxic effects; when applied to sea urchin eggs they caused cleavage inhibition and anomalies in a dose-dependent manner (ED50 +/- S. E. M. = 2.59 +/- 0.08 mg/ml for C. spinosus and 1.23 +/- 0.07 mg/ml for D. hystrix); moreover, hemolysis occurred with an ED50 = 0.76 mg/ml of 0.5% mouse erythrocyte suspensions to C. spinosus and 0.59 mg/ml to D. hystrix. These secretions were not lethal in acute toxicity tests, even at 335 mg/ml. The neurotoxic components were thermolabile while the hemolytic activity was resistant to boiling. Tests with the secretion from S. spengleri did not show cytotoxic effects but promptly blocked action potentials of crustacean nerves and were lethal for mice in acute toxicity rests. When applied to groupers, the C. spinosus secretion caused cardiorespiratory alterations. These results suggest the presence of neurotoxins (other than tetrodotoxin) and cytotoxins in skin of diodontid puffer fish.


Assuntos
Venenos de Peixe/metabolismo , Pele/química , Animais , Antineoplásicos/toxicidade , Citotoxinas/metabolismo , Citotoxinas/toxicidade , Potenciais Evocados/efeitos dos fármacos , Venenos de Peixe/toxicidade , Peixes Venenosos , Frequência Cardíaca/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Camundongos , Mucosa/química , Mucosa/metabolismo , Neurotoxinas/metabolismo , Neurotoxinas/toxicidade , Respiração/efeitos dos fármacos , Pele/metabolismo
18.
Toxicon ; 35(2): 305-9, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9080587

RESUMO

The few reports about diatom toxins are related to central nervous system toxicity, induced by domoic acid. In the present work Nitzschia sp. (Bacillariophyceae) was studied. The cells were cultured in f/2 medium, under 4000 lux and 14/10 hr light/dark cycle. After massive growth (5 x 10(6) cells/ml) the diatom cells were filtered, and an extract was prepared and partitioned in two fractions (polar and apolar). After cell harvesting by filtration, the diatom cells were shaken in artificial sea water to extract the water-soluble extracellular matrix (mucilage). An extract was prepared with the washed cells (free of mucilage), and polar and apolar fractions were obtained. Hemolytic assays were performed using 4.0 and 0.5% erythrocyte suspensions. Both the diatom polar and apolar fractions showed hemolytic activity. The membrane phospholipid sphingomyelin was tested as an acceptor for the hemolysins in the polar and apolar fractions. The mucilage did not exhibit hemolytic activity.


Assuntos
Diatomáceas/química , Proteínas Hemolisinas/isolamento & purificação , Toxinas Marinhas/farmacologia , Animais , Sangue/efeitos dos fármacos , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacologia , Toxinas Marinhas/metabolismo , Camundongos , Esfingomielinas/metabolismo
19.
Toxicon ; 33(8): 1025-31, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8533136

RESUMO

Caissarone, a sea anemone iminopurine, produced an increase in the twitch response of the electrically stimulated guinea-pig ileum-myenteric plexus. In the same assay, caissarone reduced the inhibitory response to the endogenous neuromodulator, adenosine, the A1 adenosine receptor agonist, R-phenylisopropyladenosine (R-PIA), and the A2 agonist, 5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA) in a dose-dependent manner. Schild plot analysis of antagonism by caissarone yielded slopes of near unity, indicating that caissarone acts as a simple competitive antagonist at the adenosine receptor. The dissociation constants (KB) for caissarone ranged from 0.53 mM to 0.78 mM. In functional nicotinic receptor assays in two human cell lines, caissarone failed either to potentiate or to reduce carbamylcholine-mediated 86Rb+ efflux. Thus, the enhancing activity of caissarone on the gut could not be attributed to activity at the ganglionic nicotinic receptor. Based on structure and pharmacological activity, caissarone appears to be the first marine product described as an adenosine receptor antagonist.


Assuntos
Venenos de Cnidários/toxicidade , Antagonistas de Receptores Purinérgicos P1 , Purinonas/toxicidade , Animais , Bioensaio , Cobaias , Humanos , Íleo , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Anêmonas-do-Mar , Células Tumorais Cultivadas
20.
Int J Food Microbiol ; 7(3): 185-91, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3275321

RESUMO

Seventy-three staphylococcal strains isolated from pyrodermatitis in dogs were classified as Staphylococcus intermedius (52 strains) or Staphylococcus aureus (21 strains) on the basis of acetoin formation, anaerobic mannitol fermentation, aerobic maltose fermentation, pigmentation, coagulation of human plasma, and reaction on crystal violet agar. Enterotoxin was produced by 13 of the 52 S. intermedius strains and 6 of the S. aureus strains. The highest percentage of enterotoxigenic strains produced enterotoxins C (6 strains), D (7 strains), and E (6 strains). Four strains produced the toxic shock syndrome toxin-1. There was little difference in the antibiotic susceptibility between the enterotoxigenic and non-enterotoxigenic strains.


Assuntos
Dermatite/veterinária , Doenças do Cão/microbiologia , Enterotoxinas/biossíntese , Infecções Estafilocócicas/veterinária , Staphylococcus/patogenicidade , Animais , Dermatite/metabolismo , Doenças do Cão/metabolismo , Cães , Infecções Estafilocócicas/metabolismo , Staphylococcus/metabolismo , Staphylococcus aureus/classificação , Staphylococcus aureus/metabolismo
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