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1.
Toxicol In Vitro ; 65: 104771, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31935486

ABSTRACT

Schistosomiasis is one of the most significant neglected tropical diseases, affecting around 260 million people worldwide, and Praziquantel is currently the only available drug for the treatment of infected persons. Thus, the search for new schistosomicidal compounds is urgent. The objective of this study was to investigate of the schistosomicidal effect of barbatic acid, a lichen metabolite, on adult worms of Schistosoma mansoni. The in vitro schistosomicidal effect was evaluated through the assessment of motility and mortality, cellular viability of the worms and ultrastructural analysis through scanning electron microscopy. To evaluate the cytotoxicity of barbatic acid, a cell viability assay was performed with human peripheral blood mononuclear cells. Barbatic acid showed a schistosomicidal effect after 3 h of exposure. At the end of 24 h the concentrations of 50-200 µM presented lethality on the worms. Motility changes were observed at sublethal concentrations. The IC50 obtained by the cell viability assay for S. mansoni was 99.43 µM. Extensive damage to the worm's tegument was observed from 25 µM. No cytotoxicity was observed on human peripheral blood mononuclear cells. This report provides data showing the schistosomicidal effect of barbatic acid on S. mansoni, causing death, motility changes and ultrastructural damage to worms. In addition, barbatic acid was shown to be non-toxic to human peripheral blood mononuclear cells at concentrations that are effective against S. mansoni.


Subject(s)
Ascomycota/chemistry , Phthalic Acids/toxicity , Schistosoma mansoni/drug effects , Animals , Cell Survival/drug effects , Cells, Cultured , Humans , Leukocytes, Mononuclear/drug effects , Lichens/chemistry , Microscopy, Electron, Scanning , Schistosoma mansoni/ultrastructure
2.
Data Brief ; 19: 1393-1397, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30225292

ABSTRACT

In this study, the molluscicidal and antiparasitic activities of divaricatic acid was evaluated, targeting the mollusc Biomphalaria glabrata and cercariae of the helminth Schistosoma mansoni. Divaricatic acid showed high toxicity against both adult snails (5.5 µg/mL) and embryos (20 µg/mL after 6 h of exposure). Similar activity was observed in S. mansoni cercariae after only a short exposure time. The divaricatic acid proved to be a promising substance for the control of the snail B. glabrata, an intermediate host of schistosomiasis, as well as the cercariae of the pathogen.

3.
Acta Trop ; 178: 97-102, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29097241

ABSTRACT

In this study, the molluscicidal and antiparasitic activities of divaricatic acid was evaluated, targeting the mollusc Biomphalaria glabrata and cercariae of the helminth Schistosoma mansoni. In addition, the environmental toxicity of divaricatic acid was assessed by bioassay using the microcrustacean Artemia salina. Divaricatic acid showed high toxicity against both adult snails (5µg/mL) and embryos (20µg/mL after 6h of exposure). Similar activity was observed in Schistosoma mansoni cercariae after only a short exposure time (10µg/mL after 30min of exposure). The divaricatic acid did not show toxicity in the acute test using Artemia salina at concentrations equal to or below 200µg/mL. The divaricatic acid proved to be a promising substance for the elimination of the snail Biomphalaria glabrata, an intermediate host of schistosomiasis, as well as the cercariae of the pathogen, while being non-toxic to the Artemia salina at the same concentrations. This is the first experimental observation of the molluscicidal and cercaricide activity of divaricatic acid.


Subject(s)
Antiparasitic Agents/pharmacology , Biomphalaria/drug effects , Depsides/pharmacology , Molluscacides/pharmacology , Schistosoma mansoni/drug effects , Animals , Artemia , Cercaria/drug effects
4.
Ultrasonics ; 73: 1-8, 2017 01.
Article in English | MEDLINE | ID: mdl-27592203

ABSTRACT

This work studies methods for efficient extraction and selection of features in the context of a decision support system based on neural networks. The data comes from ultrasonic testing of steel welded joints, in which are found three types of flaws. The discrete Fourier, wavelet and cosine transforms are applied for feature extraction. Statistical techniques such as principal component analysis and the Wilcoxon-Mann-Whitney test are used for optimal feature selection. Two different artificial neural network architectures are used for automatic classification. Through the proposed approach, it is achieved a high discrimination efficiency by using only 20 features to feed the classifier, instead of the original 2500 A-scan sample points.

6.
Braz J Biol ; 72(1): 175-80, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22437399

ABSTRACT

There are no records in Brazil for the culture of Pteridae family oysters, genus Pteria and Pinctada. The intermediate culture can be considered one of the critical stages during the oyster farming. The changes in life conditions from a semi-closed environment provided by the collector to the structures utilized for the growth represents a considerable stress factor to which the animals are subjected. The goal of the present study was to evaluate the growth and survival of the pearl oyster Pteria hirundo (Linnaeus, 1758) kept in intermediate lanterns. Seeds of P. hirundo, obtained through larviculture carried out at the Marine Molluscs Laboratory (UFSC), southern Brazil were detached from the collectors, transferred and kept in an intermediate culture system (oyster lantern). During 6 months, growth (dorso-ventral height - DVH in mm) and survival (%) were evaluated. Two size classes were tested: medium (M), between 3.4 and 4.4 mm, and large (L), bigger than 4.5 mm. The density of occupation in each floor of the lantern was 50%. At the end of the experiment, the survivals observed were 90 and 94% for the sizes M and L, respectively. Medium juveniles of Pteria hirundo had an average (Std) increase of 16.1 (±4.38) mm in the dorso-ventral height, and large juveniles an average increase of 11.4 (±3.77) mm after six months of experiment. The results observed during the intermediate stage of cultivation indicate that Pteria hirundo presents survival and growth similar to other species of pearl oysters traditionally used in the pearl industry in several countries.


Subject(s)
Aquaculture , Pinctada/growth & development , Animals , Brazil , Seasons , Survival
7.
J. venom. anim. toxins incl. trop. dis ; 17(3): 277-286, 2011. graf, tab
Article in English | LILACS | ID: lil-597226

ABSTRACT

Schistosomiasis is a major public health problem with 207 million people infected and more than 779 million at risk. The drug of choice for treating schistosomiasis is praziquantel (PZQ); however, it is inefficient against immature forms of schistosomes. The aim of this study was to test new imidazolidine derivatives LPSF/PT09 and LPSF/PT10 against adult Schistosoma mansoni worms. IC50, cytotoxicity, immune response and cell viability assays were also available for these imidazolidines. Different concentrations of imidazolidine, from 32 to 320 »M, promoted motor abnormalities in breeding and unpaired worms, and death in 24 hours at higher concentrations. Although LPSF/PT09 and LPSF/PT10 did not affect IFN-³ and IL-10 production, they induced nitric oxide production and showed a similar behavior to praziquantel on cell death test. Thus, these new imidazolidine derivatives should undergo further study to develop schistosomiasis drugs.


Subject(s)
Animals , Female , Rats , Imidazolidines/immunology , Schistosoma mansoni/immunology , Public Health
8.
Rev. bras. plantas med ; 12(1): 23-30, jan.-mar. 2010. tab
Article in Portuguese | LILACS | ID: lil-578931

ABSTRACT

O objetivo deste estudo foi verificar a influência da temperatura e da luz, em interação com a temperatura e de forma isolada, bem como, determinar a temperatura mais adequada para a condução do teste de germinação de sementes de Aristolochia esperanzae O. Kuntze (cipó mil-homens). Foram realizados três ensaios. No primeiro, as temperaturas utilizadas foram 15, 20, 25, 30, 35 e 40ºC. No segundo, foi avaliada a germinação das sementes nas temperaturas de 25, 30 e 35ºC, na presença e ausência de luz e no terceiro ensaio, foram testadas quatro condições de luminosidade, de forma isolada: (a) luz branca; (b) luz vermelha; (c) vermelho-distante e (d) ausência de luz, na temperatura de 25ºC. Em ambos os ensaios, foram avaliados, durante 30 dias, as porcentagens de sementes germinadas, de plântulas normais e de sementes não germinadas, e os tempos médios de sementes germinadas e de plântulas normais. Nas temperaturas de 15ºC e de 40ºC, não ocorreram germinação de sementes de A. esperanzae. O melhor resultado para sementes germinadas e para formação de plântulas normais (96 por cento) foi obtido na temperatura de 30ºC. A presença de luz e as temperaturas de 25ºC e 30ºC favoreceram a germinação de sementes e a formação de plântulas normais. As sementes de Aristolochia esperanzae tiveram sua germinação inibida na ausência de luz, caracterizando-as como fotoblásticas positivas.


The aim of this study was to verify the influence of temperature and light, interacting or separately, as well as to establish the most suitable temperature to conduct the germination test of Aristolochia esperanzae O. Kuntze ("cipó mil-homens") seeds. Three assays were performed. In the first one, temperatures were 15, 20, 25, 30, 35 and 40ºC. In the second assay, seed germination was evaluated at 25, 30 and 35ºC, in the presence and absence of light. In the third assay, four light conditions were tested separately: (a) white light; (b) red light; (c) far-red light; and (d) no light, at 25ºC. In all assays, the percentages of germinated seeds, normal seedlings and non-germinated seeds, besides the mean times of germinated seeds and normal seedlings, were evaluated during 30 days. At 15ºC and 40ºC, there was no A. esperanzae seed germination. The best result for germinated seeds and normal seedlings (96 percent) was obtained at 30ºC. The presence of light and the temperatures 25ºC and 30ºC favored seed germination and normal seedling formation. Aristolochia esperanzae seeds had their germination inhibited in the absence of light, which characterizes them as positive photoblastic.


Subject(s)
Aristolochia , Germination , Light , Physical Phenomena , Seeds/growth & development , Temperature , Analysis of Variance , Plants, Medicinal/growth & development , Cell Survival/physiology
9.
Arq. bras. med. vet. zootec ; 60(5): 1271-1273, out. 2008.
Article in English | LILACS | ID: lil-500101

ABSTRACT

Copépodes ergasilídeos coletados nas brânquias de Curimatella lepidura do reservatório de Três Marias, alto rio São Francisco, Minas Gerais, Brasil e identificados como Miracetyma etimaruya e Ergasilus sp., constituem o primeiro registro de parasitos nesse peixe forrageiro e endêmico. A ocorrência foi independente do sexo e do tamanho dos peixes. A distribuição geográfica conhecida das espécies de Miracetyma Malta, 1993, restrita à bacia do rio Amazonas, é ampliada neste estudo para a bacia do rio São Francisco.


Subject(s)
Animals , Copepoda/classification , Fishes , Parasitic Diseases
10.
Pharmazie ; 60(1): 13-7, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15700773

ABSTRACT

Synthesis and physico-chemical properties of 3-benzyl-5-(4-fluoro-benzylidene)-1-methyl-2-thioxo-imidazolidin-4-ones, 5-benzylidene-3-(4-nitro-benzyl)-2-thioxo-imidazolidin-4-ones and 4-acridin-9-ylmethylene-1-benzyl-5-thioxo-imidazolidin-2-ones compounds are described. These thioxo-imidazolidine derivatives were prepared by alkylation and condensation with 4-fluoro-benzaldehyde or nucleophilic Michael addition with cyanoacrylates. The schistosomicidal activity of 3-benzyl-5-(4-fluoro-benzylidene)-1-methyl-2-thioxo-imidazolidin-4-one compounds was evaluated.


Subject(s)
Imidazolidines/chemical synthesis , Imidazolidines/pharmacology , Schistosomicides/chemical synthesis , Schistosomicides/pharmacology , Animals , Crystallography, X-Ray , Female , Indicators and Reagents , Magnetic Resonance Spectroscopy , Male , Mice , Schistosoma mansoni/drug effects , Schistosomicides/toxicity
11.
J Clin Microbiol ; 39(3): 1157-60, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11230448

ABSTRACT

Human rotavirus strains belonging to genotype G9 or P[9] were detected in a collection of stool specimens from children with diarrhea in two cities of the state of Rio de Janeiro, Brazil, between March 1997 and December 1999. G9 strains were first detected in April 1997 and remained prevalent until the end of the study, at a frequency of 15.9% (n = 157). A high percentage of VP7 nucleotide (99.0 to 99.5%) and deduced amino acid identity (98.6 to 99.1%) was found between three randomly selected Brazilian G9 strains and the American G9 strain US1205. A novel G9:P[4] genotype combination was detected in addition to G9:P[8] and G9:P[6], demonstrating that this G genotype may undergo constant genetic reassortment in nature. The P[9] rotavirus strains constituted 10.2%, the majority of which were detected between April and July 1997. The RNA electrophoretic migration pattern of the G3:P[9] strains resembled that of AU-1 virus (G3:P3[9]), suggesting a genetic similarity between the Brazilian G3:P[9] strains and the Japanese virus, which is similar to a feline rotavirus genetically.


Subject(s)
Antigens, Viral , Capsid Proteins , Diarrhea/virology , Rotavirus Infections/virology , Rotavirus/classification , Rotavirus/genetics , Bacterial Typing Techniques , Brazil/epidemiology , Capsid/genetics , Child, Preschool , Diarrhea/epidemiology , Electrophoresis, Polyacrylamide Gel , Genotype , Humans , Molecular Sequence Data , Rotavirus/isolation & purification , Rotavirus Infections/epidemiology , Sequence Analysis, DNA
13.
Rev Bras Enferm ; 51(1): 35-52, 1998.
Article in Portuguese | MEDLINE | ID: mdl-10776269

ABSTRACT

This work has evaluated the application of relaxation as a strategy of nursing care; it has also sought for a theoretical framework that could base this technique application to assist the needs of a client facing his illness status, as well as a resource to be used by nurses in dealing with stressing situations, regarding to their professional praxis. We have worked upon conceptual aspects, the etymology, the aims, relaxation application and its implication in nursing care. We have concluded that relaxation technique is an ability that needs to be learned and pratice in order to improve well-being. It is a therapeutic modality, not pharmacologic, can be associated to traditional therapeutics and is of preventive value. It increases the options of efficient therapy for nurses. It is a coping technique in relation to stress. For inserting it into nursing praxis it is demanding that the nurse perceive the client and himself as a whole for both are benefitted by this strategy use.


Subject(s)
Relaxation Therapy , Stress, Psychological/nursing , Stress, Psychological/prevention & control , Adaptation, Psychological , Humans , Nurse-Patient Relations , Nursing Process , Nursing Theory , Stress, Psychological/psychology
14.
GED gastroenterol. endosc. dig ; 16(1): 14-8, jan.-fev. 1997. tab
Article in Portuguese | LILACS | ID: lil-213353

ABSTRACT

A partir de um estudo retrospectivo realizado no Serviço de Endoscopia do Hospital das Clínicas-UFPE, em 10.230 exames de endoscopia digestiva alta efetuados nos anos de 91, 92 e 93 foram diagnosticados 60 casos de adenocarcinoma gástrico, resultando em incidência de 0,58 por cento da amostra. Os 60 casos estudados mostram dados rigorosamente semelhantes aos publicados na literatura mundial quanto aos aspectos epidemiológicos (idade e sexo), clínicos (dor em abdome superior, perda de peso, etc.) e localizaçao da lesao (antro e corpo). Por outro lado, encontramos baixíssimo índice de diagnóstico de câncer precoce (1,6 por cento) e elevada incidência do tipo histológico difuso (46 por cento), indiferenciado. Noventa por cento das lesoes eram Bormann III e IV. Esses três fatos podem estar relacionados com baixa suspeiçao em relaçao às lesoes precoces e/ou precursoras ou ainda a comportamento biológico mais agressivo do adenocarcinoma em nossa regiao, incluindo aí fatores ambientais diferenciados quando comparados com outras áreas de elevada incidência.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Stomach Neoplasms/epidemiology , Aged, 80 and over , Brazil , Incidence , Stomach Neoplasms/diagnosis , Retrospective Studies
15.
Biochem J ; 309 ( Pt 1): 105-12, 1995 Jul 01.
Article in English | MEDLINE | ID: mdl-7619043

ABSTRACT

After tissue homogenization, 43% of the total hexokinase activity found in maize radicles was recovered in the mitochondrial fraction and 35% was soluble, in the cytosol. The maize submitochondrial particles obtained after mitochondrial sonication retained a high hexokinase activity. The mitochondrial respiration (state 4 rate) was activated by glucose. This activation was blocked by carboxyatractyloside (0.5 mM) and by oligomycin (2 micrograms/ml). The affinities for ATP and glucose of both soluble and membrane-bound maize hexokinases are similar to those of yeast hexokinase. The Km for ATP of these different forms of hexokinase varied between 0.15 and 0.37 mM, and the Km for glucose between 0.05 and 0.13 mM. A major difference between the two maize hexokinase forms is that only the mitochondrial enzyme was strongly inhibited by ADP (Ki 0.04 mM). The soluble forms of hexokinase found both in the cytosol of maize radicles and in yeast are not inhibited by ADP. In a previous report [de Meis, Grieco and Galina (1992) FEBS Lett. 308, 197-201] it was shown that the mitochondrial F1-F0-ATPase can use glucose 6-phosphate and yeast hexokinase as an ATP regenerating system. We now show that the membrane-bound hexokinase and glucose 6-phosphate can also serve as an ATP regenerating system for the mitochondria of maize radicles provided that the ADP concentration is kept below 0.05 mM. Higher ADP concentrations inhibit the reverse reaction of the mitochondrial hexokinase.


Subject(s)
Cytosol/enzymology , Hexokinase/metabolism , Mitochondria/enzymology , Plant Roots/enzymology , Zea mays/enzymology , Adenosine Diphosphate/pharmacology , Adenosine Triphosphate/biosynthesis , Glucose-6-Phosphate , Glucosephosphates/pharmacology , Hexokinase/antagonists & inhibitors , Kinetics , Mitochondria/metabolism , Oxygen/metabolism
16.
Rev Lat Am Enfermagem ; 3(2): 131-43, 1995 Jul.
Article in Spanish | MEDLINE | ID: mdl-7551075

ABSTRACT

The present study aims at demonstrating the situation of nurses of a particular hospital institution with respect to nursing research, focusing their previous and actual research, the limited and favourable elements to elaborate scientific works and the meaning of research to nursing, according to this study participant's opinion. The data collection were made through questionnaire and semi-structured interview.


Subject(s)
Nursing Assistants , Nursing Research , Health Knowledge, Attitudes, Practice , Humans , Nursing Assistants/psychology , Nursing Assistants/statistics & numerical data , Nursing Methodology Research , Personnel, Hospital , Surveys and Questionnaires
17.
Article in English | MEDLINE | ID: mdl-7656187

ABSTRACT

Trout and rabbit (Ca2+ + Mg2+)-ATPases from sarcoplasmic reticulum were compared for differences in thermal inactivation and susceptibility to trypsin digestion. The trout ATPase is more heat-sensitive than the rabbit ATPase and is stabilized by Ca2+, Na+, K+ and nucleotides. Solubilization of both ATPases shows that the two ATPases have different protein-intrinsic inactivation kinetics. When digested by trypsin, the two ATPases display different cleavage patterns. The present results indicate that the trout and rabbit ATPases have dissimilarities in protein structure that may explain the differences in thermal inactivation kinetics.


Subject(s)
Ca(2+) Mg(2+)-ATPase/metabolism , Sarcoplasmic Reticulum/enzymology , Animals , Ca(2+) Mg(2+)-ATPase/physiology , Dose-Response Relationship, Drug , Enzyme Activation/physiology , Enzyme Stability/drug effects , Enzyme Stability/physiology , Hot Temperature , Hydrogen-Ion Concentration , Kinetics , Ligands , Lithium/pharmacology , Molecular Weight , Muscle, Skeletal/enzymology , Muscle, Skeletal/metabolism , Octoxynol/pharmacology , Potassium/pharmacology , Protein Conformation/drug effects , Rabbits , Sarcoplasmic Reticulum/metabolism , Sodium/pharmacology , Solubility , Spectrometry, Fluorescence , Trout , Trypsin/metabolism
18.
Biochem J ; 293 ( Pt 2): 469-73, 1993 Jul 15.
Article in English | MEDLINE | ID: mdl-8343126

ABSTRACT

The phosphorylation of the trout sarcoplasmic-reticulum Ca(2+)-ATPase by Pi differs in its temperature- and pH-dependence from the rabbit ATPase. In the trout enzyme, the apparent affinity for Pi and maximum phosphoenzyme values do not vary over a pH and temperature ranges that have a pronounced effect on the rabbit enzyme. The lack of temperature-dependence for phosphorylation is observed at pH 6.8. At pH 8.0, the temperature profile for phosphorylation of the trout enzyme resembles that of the rabbit at pH 6.8. The rabbit ATPase is no longer phosphorylated by Pi after solubilization with the detergent C12E9. In contrast, the trout enzyme can be phosphorylated by Pi after solubilization with C12E9, and the same levels of phosphoenzyme were obtained with the soluble and membrane-bound ATPase at both 0 degrees and 25 degrees C. In the range of 0-20 degrees C, the rates of ATP synthesis and of Ca2+ uptake by the trout ATPase are less temperature-dependent than for the rabbit enzyme. However, both isoenzymes catalyse ATP hydrolysis with similar temperature-dependences. The results raise the possibility that protonation of specific amino acid residues may contribute to the lack of temperature-dependence for phosphorylation of the trout Ca(2+)-ATPase.


Subject(s)
Calcium-Transporting ATPases/metabolism , Adenosine Triphosphate/biosynthesis , Animals , Calcium/metabolism , Detergents , Hydrogen-Ion Concentration , Hydrolysis , Muscles/enzymology , Phosphates/metabolism , Phosphorylation , Rabbits , Solubility , Species Specificity , Temperature , Trout
19.
Rev. Inst. Med. Trop. Säo Paulo ; 30(3): 169-73, maio-jun. 1988. tab
Article in Portuguese | LILACS | ID: lil-53160

ABSTRACT

O trabalho apresenta os princípios metodológicos que nortearam a organizaçäo da Pesquisa Inquérito Nutricional no Polonoroeste. Foram incluídas, também as informaçöes sobre as característics sócio-econômicas e sanitárias das famílias estudadas em 1985 na zona urbana de Cáceres-MT. Destas 74% eram radicadas em Cáceres e 13,5% provinham de outros estados ou de outros países, sendo que 76,2% residiam em zona urbana. Quanto a categoria social e renda 52% eram urbanos e 51,0% recebia menos de 2 salários mínimos. O inquérito näo atingia os 2 setores mais pobres e populosos da cidade onde as condiçöes säo piores e onde vive a maioria da populaçäo que migrou mais recentemente para Cáceres


Subject(s)
Infant , Child, Preschool , Child , Humans , Male , Female , Nutritional Status , Socioeconomic Factors , Brazil
20.
Rev. Inst. Med. Trop. Säo Paulo ; 30(3): 174-8, maio-jun. 1988. tab
Article in Portuguese | LILACS | ID: lil-53161

ABSTRACT

Realizou-se o estudo do estado nutricional através da antropometria com o objetivo de descrever a prevalência e a forma da Desnutriçäo Protéico-Energética em seis cidades da regiäo do Polonoroeste. O exame antropométrico foi aplicado em um grupo de 573 crianças de 3 a 72 meses de idade, de ambos os sexos. Para o tratamento dos dados coletadoss utilizou-se as classificaçöes propostas por GOMEZ e por WATERLOW, sendo ainda realizada a distribuiçäo do peso e a altura por faixas de percentis. A prevalência de desnutriçäo encontrada, segundo a classificaçäo de GOMEZ, foi de 51,0%, sendo que o maior percentual foi constatado na cidade de Jauru (79,2%) e o menor na cidade de Araputanga (31,3%). Quanto à forma de desnutriçäo a de maior prevalência foi a desnutriçäo pregressa, mostrando com isso um comprometimento acentuado da estatura, confirmado através da distribuiçäo por percentis


Subject(s)
Infant , Child, Preschool , Child , Humans , Male , Female , Anthropometry , Nutritional Status , Protein-Energy Malnutrition , Brazil
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