RESUMO
Salmonella enterica subsp enterica serovar 4,5,12:i:- has been responsible for many recent Salmonella outbreaks worldwide. Several studies indicate that this serovar originated from S. enterica subsp enterica serovar Typhimurium, by the loss of the flagellar phase II gene (fljB) and adjacent sequences. However, at least two different clones of S. enterica 4,5,12:i:- exist that differs in the molecular events responsible for fljB deletion. The aim of this study was to test the stability of the fljBA operon responsible for the flagellar phase variation under different growth conditions in order to verify if its deletion is a frequent event that could explain the origin and dissemination of this serovar. In fact, coding sequences for transposons are present near this operon and in some strains, such as S. enterica Typhimurium LT2, the Fels-2 prophage gene is inserted near this operon. The presence of mobile DNA could confer instability to this region. In order to examine this, the cat (chloramphenicol acetyltransferase) gene was inserted adjacent to the fljBA operon so that deletions involving this genomic region could be identified. After growing S. enterica chloramphenicol-resistant strains under different conditions, more than 104 colonies were tested for the loss of chloramphenicol resistance. However, none of the colonies were sensitive to chloramphenicol. These data suggest that the origin of S. enterica serovar 4,5,12:i:- from Typhimurium by fljBA deletion is not a frequent event. The origin and dissemination of 4,5,12:i:- raise several questions about the role of flagellar phase variation in virulence.
Assuntos
Óperon , Salmonella typhimurium/genética , Animais , Antibacterianos/farmacologia , Sequência de DNA Instável , DNA Bacteriano/genética , Farmacorresistência Bacteriana/genética , Evolução Molecular , Feminino , Genes Bacterianos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Mitomicina/farmacologia , Infecções por Salmonella/microbiologiaRESUMO
Small cell lung cancer (SCLC) is an aggressive disease, representing 15% of all cases of lung cancer, has high metastatic potential and low prognosis that urgently demands the development of novel therapeutic approaches. One of the proposed approaches has been the down-regulation of BCL2, with poorly clarified and controversial therapeutic value regarding SCLC. The use of anti-BCL2 small interfering RNA (siRNA) in SCLC has never been reported. The aim of the present study was to select and test the in vitro efficacy of anti-BCL2 siRNA sequences against the protein and mRNA levels of SCLC cells, and their effects on cytotoxicity and chemosensitization. Two anti-BCL2 siRNAs and the anti-BCL2 G3139 oligodeoxynucleotide (ODN) were evaluated in SCLC cells by the simultaneous determination of Bcl-2 and viability using a flow cytometry method recently developed by us in addition to Western blot, real-time reverse-transcription PCR, and cell growth after single and combined treatment with cisplatin. In contrast to previous reports about the use of ODN, a heterogeneous and up to 80% sequence-specific Bcl-2 protein knockdown was observed in the SW2, H2171 and H69 SCLC cell lines, although without significant sequence-specific reduction of cell viability, cell growth, or sensitization to cisplatin. Our results question previous data generated with antisense ODN and supporting the present concept of the therapeutic interest in BCL2 silencing per se in SCLC, and support the growing notion of the necessity of a multitargeting molecular approach for the treatment of cancer.
Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Oligorribonucleotídeos Antissenso/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/farmacologia , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Antineoplásicos/farmacologia , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Regulação para Baixo , Citometria de Fluxo , Inativação Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carcinoma de Pequenas Células do Pulmão/metabolismo , Células Tumorais CultivadasRESUMO
Small cell lung cancer (SCLC) is an aggressive disease, representing 15 percent of all cases of lung cancer, has high metastatic potential and low prognosis that urgently demands the development of novel therapeutic approaches. One of the proposed approaches has been the down-regulation of BCL2, with poorly clarified and controversial therapeutic value regarding SCLC. The use of anti-BCL2 small interfering RNA (siRNA) in SCLC has never been reported. The aim of the present study was to select and test the in vitro efficacy of anti-BCL2 siRNA sequences against the protein and mRNA levels of SCLC cells, and their effects on cytotoxicity and chemosensitization. Two anti-BCL2 siRNAs and the anti-BCL2 G3139 oligodeoxynucleotide (ODN) were evaluated in SCLC cells by the simultaneous determination of Bcl-2 and viability using a flow cytometry method recently developed by us in addition to Western blot, real-time reverse-transcription PCR, and cell growth after single and combined treatment with cisplatin. In contrast to previous reports about the use of ODN, a heterogeneous and up to 80 percent sequence-specific Bcl-2 protein knockdown was observed in the SW2, H2171 and H69 SCLC cell lines, although without significant sequence-specific reduction of cell viability, cell growth, or sensitization to cisplatin. Our results question previous data generated with antisense ODN and supporting the present concept of the therapeutic interest in BCL2 silencing per se in SCLC, and support the growing notion of the necessity of a multitargeting molecular approach for the treatment of cancer.
Assuntos
Humanos , Neoplasias Pulmonares/tratamento farmacológico , Oligorribonucleotídeos Antissenso/farmacologia , /metabolismo , RNA Interferente Pequeno/farmacologia , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Antineoplásicos/farmacologia , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Regulação para Baixo , Citometria de Fluxo , Inativação Gênica , Neoplasias Pulmonares/metabolismo , /efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carcinoma de Pequenas Células do Pulmão/metabolismo , Células Tumorais CultivadasRESUMO
Applications of niclosamide at three-monthly intervals were undertaken for 14 years in foci of Biomphalaria glabrata in the water sources of Peri-Peri (Capim Branco, MG). All the residents of the area were submitted to an annual fecal examination (Kato/Katz) and those individuals eliminating Schistosoma mansoni eggs were treated with oxamniquine. A malacological survey was undertaken at three-monthly intervals by means of ten scoops with a perforated ladle each ten metres along the two banks of the ditches and streams of the region. Where snails were found, molluscicide was applied by means of dripping or aspersion using a 3 ppm aqueous suspension of niclosamide. Initially, a mean of 14.3% of snails in the region were found to be eliminating cercariae. Following the first four applications of molluscicide, this was reduced to 0.0% and maintained at about 1.5% throughout the program. Thus, there was a continued possibility of schistosomiasis transmission in the area and it was observed that the population of snails reestablished itself within three months of molluscicide application. The results obtained in this study do not encourage the continual use of niclosamide as the only method of control of schistosomiasis.
Assuntos
Biomphalaria , Vetores de Doenças , Moluscocidas , Niclosamida , Schistosoma mansoni , Animais , Biomphalaria/parasitologia , Brasil , Reservatórios de Doenças , Fezes/parasitologia , Fatores de TempoRESUMO
Bioassays using hexanolic extracts of cashew nut shells, of Anacardium occidentale, collected in Ceará in 1972 (Sample 1) and 1987 (Sample 2) were undertaken with adult snails and egg masses of Biomphalaria glabrata, B. tenagophila and B. straminea both in the laboratory and in the field. Non extracted shells, 18.5 g, sample 1, were also tested with adult snails and egg masses of the three species. The toxicity of extract was tested with fish (Poecilia reticulata) and tadpoles. The lethal concentration, CL90, of sample 1 was from 2.0 to 2.2 ppm for adult snails of the three species. With sample 2, the CL90 was 2.0, 0.5 and 30.0 ppm for B. glabrata adults, newly hatched snails and egg mass respectively. Non extracted shells caused 40-80% mortality of adult snails, 22-35% mortality of embryos and 40-55% reduction of egg production. The hexanolic extract, sample 2, were innocuous for tadpole and fish at 2 ppm. In the field, in pools of still water treatment with 20 ppm of extract, sample 1, caused a 97.1% mortality of B. straminea and 100% mortality of B. glabrata and B. tenagophila. Using Niclosamide, at 3 ppm, 100% mortality of the three species occurred.
Assuntos
Moluscocidas , Nozes , Animais , Bioensaio , Biomphalaria/parasitologia , Brasil , Vetores de Doenças , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Moluscocidas/toxicidade , Extratos Vegetais/toxicidade , Poecilia , Ranidae , Schistosoma mansoniRESUMO
Hydrolates and essential oils of several Eucalyptus species were tested on adult snails and egg masses of Biomphalaria glabrata, and cercaria of Schistosoma mansoni. These products were obtained by vapor dragging. Eight out of 21 hydrolates presented activity on snails, nine on egg masses and three on cercaria at 1:4 dilutions. Eleven oils were active on both snails and egg masses at 20 ppm concentrations. The hydrolate of E. deanei was active both on snails, egg masses and cercaria at 1:4 dilution and its essential oil at 20 ppm.
Assuntos
Biomphalaria , Eucalyptus , Plantas Medicinais , Schistosoma mansoni , Animais , Extratos Vegetais , Especificidade da EspécieRESUMO
The molluscicide activity of hexanic extract from Anacardium occidentale L. (cashew) nut shell, of copper (II) complex, of lead (II) complex and anacardic acid has been compared in the laboratory in an attempt to obtain better stability than anacardic acid. This was obtained from the hexanic extract of the cashew nut shell by precipitation with lead (II) hydroxide or cupric sulfate plus sodium hydroxide or (II) cupric hydroxide followed by treatment of lead (II) complex with a diluted solution of sulfuric acid. Ten products of the mixture obtained were tested on adults snails of Biomphalaria glabrata at 1 to 10 ppm. The most active products were copper (II) complex, obtained by cupric sulfate plus sodium hydroxide, and anacardic acid (sodium hydroxide) which presented activity at 4 ppm. The anacardic acid's lead content was above the limits accepted by the United States standards.
Assuntos
Biomphalaria , Chumbo , Moluscocidas , Compostos Organometálicos , Salicilatos , Animais , Chumbo/química , Moluscocidas/síntese química , Compostos Organometálicos/síntese química , Salicilatos/síntese químicaRESUMO
Extratos brutos, etanólicos, hexânicos, liofilizados de diversos vegetais e ácido anacárdico foram testados quanto a sua influência sobre o comportamento de oviposiçäo das fêmeas de Aedes fluviatilis (Lutz), nas concentraçöes de 100, 10 e 1 ppm. Os estratos de Allium sativum, jatropha curcas. MiKania schenkii, Poinciana regia s Spatodea campanulata mostraram-se repelentes (alfa = 0,05) para as fêmeas na concentraçäo de 100 ppm e os de Anacardium occidentale, Bidens segetum e Caesalpinia peltophoroides também na de 10 ppm. Os extratos Coriandrum stivum (100, 10 e 1 ppm), chara zeylanica (10 ppm), Cupressus sempervirens (10 ppm), Foeniculum vulgare (10 ppm) e Spatodea campanulata (1 ppm) atrairam a oviposiçäo das fêmeas; 13 (52,0%) dos extratos testados foram indiferentes as fêmeas nas concentraçöes utilizadas
Assuntos
Animais , Aedes , Comportamento Animal/efeitos dos fármacos , Oviposição , Extratos VegetaisRESUMO
The larvicidal properties of 34 plant extracts were tested against Aedes fluviatilis (Lutz) (Diptera: Culicidae) larvae, at 100, 10 and 1 ppm concentrations; 26.6% of the extracts enhanced larval mortality (alpha = 0.05) at 100 ppm (Anacardium occidentale, Agave americana, Allium sativum, Coriandrum sativum, Nerium oleander, Spatodea campanulata, Tibouchina scrobiculata and Vernonia salzmanni). Anacardic acid (A. occidentale) was effective at 10 ppm and A. sativum (crude extract) at 1 ppm.
Assuntos
Aedes , Inseticidas , Extratos Vegetais , AnimaisRESUMO
To assess the usefulness of cord blood tests in diagnosing ABO-haemolytic disease of the newborn (ABO-HDN), 132 term, adequate for gestational age (AGA) neonates were evaluated. The tests studied and their significant results were: quantitative elution test (greater than or equal to 1/16), direct Coombs test (positive), bilirubin concentration (greater than or equal to 4 mg/dl). In none of the 56 O+ newborn infants delivered by O+ women were the results of any test positive. Of the 76 A+ and B+ newborn infants delivered by O+ women, 17 (22%) developed ABO-HDN. When the combined result of any two tests was positive, the sensitivity, the specificity and the positive predictive accuracy for the diagnosis of ABO-HDN was higher than for any one of the isolated tests. The probability that ABO-HDN was present when the results of at least two cord blood tests were positive was 70%, and the probability that ABO-HDN was not present when less than two cord blood tests gave positive results was 93%. It is suggested that the combination of quantitative elution test, bilirubin concentration and direct Coombs test in the cord blood is useful for an early diagnosis of ABO-HDN.
Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Eritroblastose Fetal/genética , Teste de Coombs , Eritroblastose Fetal/diagnóstico , Humanos , Recém-Nascido , Icterícia Neonatal/genética , Fenótipo , PrognósticoRESUMO
The molluscicide activity of aqueous (macerated and boiled), hexanic and ethylic extracts of Aristolochia brasiliensis, Caesalpinia peltophoroides, Caesalpinia pulcherrima, Delonix regia, Spathodea campanulata and Tibouchina scrobiculata was evaluated in the laboratory. The solutions obtained from those extracts were tested on adults and egg masses of Biomphalaria glabrata reared in the laboratory at 1, 10, 20, 100 and 1000 ppm concentrations. The most active of the extracts studied was D. regia flowers' (flamboyant) ethylic extracts which presented molluscicidal activity on adult snails at 20 ppm.
Assuntos
Biomphalaria/efeitos dos fármacos , Moluscocidas , Extratos Vegetais/farmacologia , AnimaisAssuntos
Biomphalaria , Moluscocidas , Extratos Vegetais , Animais , Feminino , Oviposição/efeitos dos fármacos , Controle de PragasRESUMO
Estudou-se em laboratorio a atividade moluscicida de 68 extratos de 23 plantas brasileiras. As solucoes em agua desclorada dos extratos hexanicos e etanolico, nas concentracoes de 1,10 e 100 ppm, foram testadas sobre caramujos adultos e desovas de Biomphalaria glabrata, criados em laboratorio. As plantas que demostraram acao moluscicida na concentracao de 100 ppm foram: Arthemisia verlotorum Lamotte, Caesalpinia peltophoroides Benth, Cassia rugosa G.Don., Eclipta alba Hassk, Euphorbia pulcherrima Willd, Euphorbia splendens Bojer, Joannesia princeps Vell, Leonorus sibiricus L., Macrosiphonia guaranitica Mell Nerium oleander L., Palicourea nicotianaefolia Cham. e Schlech., Panicum maximum M.Rumex crispus L., Ruta graveolens L., e Stryphnodendron barbatiman M
Assuntos
Animais , Biomphalaria , Extratos Vegetais , MoluscocidasRESUMO
O objetivo do estudo foi verificar se haveria diferencas intraespecificas marcantes entre populacoes de Biomphalaria glabrata que habitam criadouros proximos. Foram estudadas 12 populacoes, procedentes do Municipio de Belo Horizonte, Minas Gerais, Brasil. Parte dos descendentes desses moluscos foram infectados com duas cepas de Schistosoma mansoni; "LE", de origem local e "SJ", procedente de Sao Jose dos Campos, Sao Paulo. Outra parte foi usada em ensaios biologicos com os moluscicidas bayluscide (niclosamida) e pentaclorofenol. Os resultados mostraram que existem diferencas na suscetibilidade dos moluscos as duas cepas de S. mansoni. As taxas de infeccao com a cepa "LE" variaram de 27,0 a 94,0% e com "SJ", de 9,0 a 61,0%. Houve diferenca na duracao do periodo de adaptacao dos caramujos as condicoes de laboratorio. Nao houve diferenca estatisticamente significante na suscetibilidade desses moluscos ao bayluscide e pentaclorofenol. Nao houve indicacao de desenvolvimento de resistencia nos moluscos apesar do bayluscide ter sido usado intermitentemente nessa area durante os ultimos 20 anos
Assuntos
Animais , Biomphalaria , Moluscocidas , Pentaclorofenol , Schistosoma mansoni , BrasilRESUMO
Procedeu-se ao levantamento malacologico do municipio de Belo Horizonte, MG, com o objetivo de avaliar a distribuicao, densidade e taxa de infeccao dos moluscos hospedeiros intermediarios do Schistosoma mansoni. Foram coletadas 3.261 Biomphalaria glabrata em 1979-81, das quais 100 (3,1%) estavam infectadas com S. mansoni. Registrou-se a existencia de 36 criadouros (35,0%) de B. glabrata em 102 locais pesquisados, sendo 23 na bacia hidrografica de Pampulha e 13 na do ribeirao do Arrudas. Foram encontrados 2 criadouros de B. tenagophila e 2 de B. straminea. Registrou-se tambem a presenca de exemplares de Pomacea haustrum, Physa sp e Drepanotrema cimex. Compararam-se os dados obtidos atualmente com os publicados em 1967. Houve reducao de mais de 50% no numero de criadouros de B.glabrata, principalmente em decorrencias da expansao e progresso da cidade. Na zona periferica a esquistossomose continua endemica, havendo necessidade de novas obras de saneamento basico para se conseguir o controle da doenca
Assuntos
Biomphalaria , Schistosoma mansoni , BrasilAssuntos
Moluscocidas , Nitroquinolinas/uso terapêutico , Oxamniquine/uso terapêutico , Esquistossomose/prevenção & controle , Adolescente , Adulto , Fatores Etários , Animais , Biomphalaria/parasitologia , Brasil , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Niclosamida , Oxamniquine/efeitos adversos , Schistosoma mansoni , Esquistossomose/tratamento farmacológicoRESUMO
The influence of EDTA on B. glabrata has been investigated. Newly hatched snails were exposed to concentrations of EDTA from 1 to 64 ppm, and young (diameter of 6 mm) snails to concentrations of 50, 80 and 100 ppm, for periods of 90 days. Fifty percent reduction of egg productivity has been caused by concentration of 16 ppm of EDTA while 50% of mortality has occurred at about 70 ppm. The calcium and iron content both in treated and non-treated young snails have been estimated by atomic absorption photometry. The uptake of calcium was 40, 83 and 90% less for calcium and 37, 77 and 81% less for iron as compared with the untreated group. The calcium content of the shell was 5--15 times greater than that of the soft body, while the iron content of those two parts was in the proportion of 1:1. These proportions were maintained constant in the treated and non-treated groups. The interference of increasing concentrations of EDTA has resulted in the proportional reduction of growth-rate, reproduction rate and of longevity of the exposed snails.
Assuntos
Biomphalaria/crescimento & desenvolvimento , Ácido Edético/farmacologia , Animais , Biomphalaria/efeitos dos fármacos , Biomphalaria/metabolismo , Cálcio/análise , Cálcio/metabolismo , Feminino , Ferro/análise , Ferro/metabolismo , Oviposição/efeitos dos fármacos , Espectrofotometria AtômicaRESUMO
The hexanic extract from the leaves of Euphorbia cotinifolia L. has been experimentally used as molluscicide against Biomphalaria glabrata. The extract was fractionated and the most actives fractions were those of numbers 6 and 7. The lethal concentrations (LC50 and LC90 obtained using fraction 6 against adult snails were 1,2 and 2,4 ppm; for the eggs they were 25,0 and 48,0 ppm. With fraction 7 the lethal concentrations were 1,4 and 3,4 ppm for adult snails; for newly hatched snails they were 4,8 and 8,0 ppm; for the eggs they were 13,0 and 31,0 ppm. In the field the hexanic extract was lethal for the snails in concentrations of 20 ppm in stagnant water. Fractions 6 and 7 were lethal for S. mansoni cercariae and to fish (Lebistes reticulatus) in concentrations below 10 ppm. For mice the extract did not display any toxity in concentrations of 600 mg/kg.