RESUMEN
Cassava (Manihot esculenta Crantz) is one of the most widely cultivated foods in the world and is of great socio-economic importance, especially in developing countries. It is predominantly consumed in boiled form, but also is used to produce a number of products, including cassava starch, sour starch, cassava flour and tapioca flour (hydrated cassava starch). Fungal spoilage can occur throughout the production chain, impairing both productivity and quality, as well as posing a potential risk of contamination by mycotoxins. We used multidisciplinary approaches based on phenotypic and molecular data (ITS/BenA/TEF-1a/RPB2 loci) to investigate the mycobiota of 101 samples (including roots, soil and products) collected in the state of São Paulo, Brazil. A total of 20 fungal groups/genera were morphologically characterized, and 37 different species were molecularly identified. The predominant groups in cassava tubers were Fusarium spp., Penicillium spp. and Trichoderma spp. In cassava products, the most frequent groups were Penicillium spp. and Paecilomyces spp. Potentially toxigenic species were also found, including Paecilomyces saturatus, Penicillium citrinum, P. paneum, P. brevicompactum, P. chrysogenum, Fusarium foetens and Fusarium mundagurra. In soil-cultivated cassava samples, the groups found most frequently were Penicillium spp., Cladosporium spp. and Fusarium spp. Some of the species found in cassava tubers and/or product samples were also present in the soil, including F. mundagurra, Neocosmospora solani, P. citrinum and P. brevicompactum. In general, there was a higher occurrence of Penicillium spp., Fusarium spp. and Trichoderma spp., and the predominant species were F. fabacearum and P. citrinum. The mycobiota of Brazilian cassava proved to be extremely diverse, and the occurrence of several species in cassava tubers and/or products are reported herein for the first time. Potentially toxigenic species were found in cassava tubers, cassava products and soil, showing how important it is to constantly monitor these substrates.
Asunto(s)
Manihot , Micobioma , Brasil , Microbiología de Alimentos , Verduras , Almidón , SueloRESUMEN
Aflatoxins are carcinogenic compounds produced by some species of Aspergillus, especially those belonging to Aspergillus section Flavi. Their occurrence in food may start in the field, in the post-harvest, or during storage due to inadequate handling and storage. Because cassava is a staple food for a high percentage of the Brazilian population, we evaluated the presence of aflatoxin-producing species in cassava tubers, cassava products (cassava flour, cassava starch, sour starch, and tapioca flour), and in soil samples collected from cassava fields. In addition, the levels of aflatoxin contamination in cassava products were quantified. A total of 101 samples were analyzed, and 45 strains of Aspergillus section Flavi were isolated. Among the identified species, Aspergillus flavus, Aspergillus arachidicola, Aspergillus novoparasiticus, and Aspergillus parasiticus were found. The majority of strains (73.3%) tested for their aflatoxin-producing ability in synthetic media was positive. Despite that, cassava and cassava products were essentially free of aflatoxins, and only one sample of cassava flour contained traces of AFB1 (0.35 µg/kg).
Asunto(s)
Aflatoxinas/análisis , Aspergillus flavus/aislamiento & purificación , Aspergillus/aislamiento & purificación , Contaminación de Alimentos/análisis , Manihot/microbiología , Aflatoxinas/clasificación , Aspergillus/clasificación , Brasil , Harina/análisis , Harina/microbiología , Suelo/químicaRESUMEN
This study evaluated the genotoxicity of lyophilized glycolic extract of Theobroma cacao Linné seeds (TCL), using the micronucleus assay in bone marrow of mice. The interaction between TCL and doxorubicin (DXR) was also analyzed. Experimental groups were evaluated 24-48 h after treatment with N-Nitroso-N-ethylurea (NEU: 50 mg/kg), DXR (5 mg/kg), NaCl (145 mM), TCL (0.5-2 g/kg), and TCL (2 g/kg) in combination with DXR (antigenotoxic assays). Analysis of micronucleated polychromatic erythrocytes (MNPCEs) showed no significant differences between all the treatment doses of TCL and NaCl control. Mice experimentally treated with DXR and NEU significantly induced MNPCEs. However, a significant reduction of MNPCEs was also observed when TCL was administered in combination with the chemotherapeutic agent DXR. The analysis of the PCE/NCE ratio revealed no significant differences between the NaCl control, all doses of TCL, and DXR. However, there were significant differences in the PCE/NCE ratio between positive NEU control and all other treatments. The PCE/NCE ratio observed after treatment with TCL and DXR showed significant differences and intermediate values to controls (NaCl and NEU). This study suggests absence of genotoxicity and cytotoxicity of TCL, regardless of dose, sex, and time. TCL reduced genotoxic effects induced by DXR, suggesting potential antigenotoxic effects.
Asunto(s)
Cacao , Animales , Daño del ADN , Doxorrubicina , Eritrocitos , Ratones , Pruebas de Micronúcleos , Extractos Vegetales/farmacologíaRESUMEN
This study evaluated the genotoxicity of lyophilized glycolic extract of Theobroma cacao Linné seeds (TCL), using the micronucleus assay in bone marrow of mice. The interaction between TCL and doxorubicin (DXR) was also analyzed. Experimental groups were evaluated 24-48 h after treatment with N-Nitroso-N-ethylurea (NEU: 50 mg/kg), DXR (5 mg/kg), NaCl (145 mM), TCL (0.5-2 g/kg), and TCL (2 g/kg) in combination with DXR (antigenotoxic assays). Analysis of micronucleated polychromatic erythrocytes (MNPCEs) showed no significant differences between all the treatment doses of TCL and NaCl control. Mice experimentally treated with DXR and NEU significantly induced MNPCEs. However, a significant reduction of MNPCEs was also observed when TCL was administered in combination with the chemotherapeutic agent DXR. The analysis of the PCE/NCE ratio revealed no significant differences between the NaCl control, all doses of TCL, and DXR. However, there were significant differences in the PCE/NCE ratio between positive NEU control and all other treatments. The PCE/NCE ratio observed after treatment with TCL and DXR showed significant differences and intermediate values to controls (NaCl and NEU). This study suggests absence of genotoxicity and cytotoxicity of TCL, regardless of dose, sex, and time. TCL reduced genotoxic effects induced by DXR, suggesting potential antigenotoxic effects.
Este estudo avaliou a genotoxicidade do extrato glicólico liofilizado de sementes de Theobroma cacao Linné (TCL), usando o ensaio do micronúcleo em medula óssea de camundongos. A interação entre TCL e doxorrubicina (DXR) foi também analisada. Grupos experimentais foram avaliados 24-48 h após tratamento com N-Nitroso-N-etilureia (NEU: 50 mg/kg), DXR (5 mg/kg), NaCl (145 mM), TCL (0,5-2 g/kg), e TCL (2 g/kg) em combinação com DXR (ensaio antigenotóxico). As análises de eritrócitos policromáticos micronucleados (EPCMNs) não mostraram diferenças significantes entre todas as doses de tratamento do TCL e o controle NaCl. Camundongos experimentalmente tratados com DXR e NEU induziram significativamente EPCMNs. Contudo, uma redução significante de EPCMNs foi também observada quando TCL foi administrada em combinação com o agente quimioterapêutico DXR. As análises da relação EPC/ENC (eritrócito policromático/eritrócito normocromático) revelaram ausência de diferenças significantes entre o controle NaCl, todas as doses de TCL e DXR. Contudo, houve diferenças significantes na relação EPC/ENC entre o controle positivo NEU e todos os outros tratamento. A relação ECP/ENC observada após o tratamento com TCL e DXR mostrou diferenças significantes e valores intermediários aos controles (NaCl e NEU). Este estudo sugere ausência de genotoxicidade e citotoxicidade de TCL, independentemente da dose, sexo e tempo. TCL reduziu os efeitos genotóxicos induzidos por DXR, sugerindo potencial efeitos antigenotóxicos.
Asunto(s)
Animales , Ratones , Daño del ADN , Cacao/toxicidad , Citotoxinas/análisis , Extractos Vegetales/farmacología , Pruebas de Micronúcleos , Doxorrubicina , EritrocitosRESUMEN
Lysinibacillus sphaericus (Bacillales: Planococcaceae) is a spore-forming bacillus used for the biological control of mosquitoes (Diptera: Culicidae) due to its larvicidal activity determined by various toxins and S-layer protein produced either during sporulation or by the vegetative cell. Aedes aegypti and Culex quinquefasciatus are the vectors of arboviruses that cause tropical diseases representing a current public health problem. Both species may coexist in the same larval development sites and are susceptible to the larvicidal activity of L. sphaericus. In this study, we compared the larvicidal effects of L. sphaericus 2362 (WHO Reference strain) and native strains III(3)7 and OT4b.25 against Cx. quinquefasciatus and Ae. aegypti in single-species and mixed-culture bioassays. Findings showed that L. sphaericus spores, vegetative cells and a combination thereof possessed high larvicidal activity against Cx. quinquefasciatus larvae, whereas only the formulation of L. sphaericus vegetative cells was effective against Ae. aegypti larvae. Similar results were obtained for field-collected larvae. We propose that a formulation of vegetative cells of L. sphaericus 2362 or III(3)7 could be a good alternative to chemical insecticides for the in situ control of mixed populations of Ae. aegypti and Cx. quinquefasciatus.
Asunto(s)
Aedes , Culex , Control Biológico de Vectores , Planococcaceae , Animales , LarvaRESUMEN
AIMS: To survey and to characterize entomopathogenic fungi as natural enemies of mosquitoes in Central Brazil. METHODS AND RESULTS: Tolypocladium cylindrosporum (Hypocreales, Ophiocordycipitaceae) was isolated for the first time in South America by using Aedes aegypti (Diptera, Culicidae) as sentinel larvae in a stagnant mosquito breeding site in a secondary tropical forest. Two isolates were morphologically and molecularly identified, and their activity tested against A. aegypti eggs, larvae and adults. CONCLUSIONS: Findings emphasize the importance of T. cylindrosporum as a natural fungal antagonist of mosquitoes. SIGNIFICANCE AND IMPACT OF THE STUDY: Both isolates affected larvae and adults but were less effective against eggs; both have potential for development as a mycoinsecticide especially against larvae of A. aegypti the main vector of dengue, chikungunya, Zika and urban yellow fever.
Asunto(s)
Aedes , Hypocreales , Control de Mosquitos/métodos , Mosquitos Vectores , Animales , Brasil , LarvaRESUMEN
Abstract Handroanthus impetiginosus has long been used in traditional medicine and various studies have determined the presence of bioactive chemical compounds and potential phytotherapeutics. In this study, the genotoxicity of the lyophilized tincture of H. impetiginosus bark (THI) was evaluated in mouse bone marrow using micronucleus assays. The interaction between THI and genotoxic effects induced by the chemotherapeutic agent, doxorubicin (DXR), was also analyzed. Experimental groups were evaluated 24 to 48 h after treatment with N-nitroso-N-ethylurea (NEU; 50 mg/kg), DXR (5 mg/kg), sodium chloride (NaCl; 150 mM), and THI (0.5-2 g/kg). Antigenotoxic assays were carried out using THI (0.5 g/kg) in combination with NEU or DXR. Analysis of the micronucleated polychromatic erythrocytes (MNPCEs) indicated no significant differences between treatment doses of THI (0.5-2 g/kg) and NaCl. Polychromatic erythrocyte (PCE) to normochromatic erythrocyte (NCE) ratios did not indicate any statistical differences between DXR and THI or NaCl, but there were differences between THI and NaCl. A significant reduction in MNPCEs and PCE/NCE ratios was observed when THI was administered in combination with DXR. This study suggested the absence of THI genotoxicity that was dose-, time-, and gender-independent and the presence of moderate systemic toxicity that was dose-independent, but time- and gender-dependent. The combination of THI and DXR also suggested antigenotoxic effects, indicating that THI reduced genotoxic effects induced by chemotherapeutic agents.
Resumo Handroanthus impetiginosus tem sido usada durante um longo período pela medicina tradicional e vários estudos têm demonstrados a presença de compostos químicos e potencial fitoterapêutico. Esta pesquisa avaliou a genotoxicidade da tintura da casca liofilizada de H. impetiginosus (THI) usando o ensaio do micronúcleo em medula óssea de camundongos. A interação entre THI e os efeitos genotóxicos induzidos pelo quimioterápico doxorrubicina (DXR) também foram analisados. Grupos experimentais foram analisados a 24-48 h após o tratamento com N-Nitroso-N-etiluréia (NEU; 50 mg/kg), DXR (5 mg/kg), NaCl (150 mM) e THI (0,5-2 g/kg). O ensaio antigenotóxico foi conduzido utilizando THI (0,5 g/kg) em combinação com NEU ou DXR. A análise de eritrócitos policromáticos micronucleados (EPCMNs) não mostrou diferenças significativas entre as doses de tratamento (0,5-2 g/kg) e NaCl. As proporções de eritrócitos policromáticos (EPC)/eritrócitos normocromáticos (ENC) não revelaram diferenças estatísticas entre DXR e THI ou NaCl, porém houve diferenças entre THI e NaCl. Uma redução significativa em EPCMNs e na razão EPC/ENC foi observada quando THI foi administrado em combinação com DXR. Essa pesquisa sugere ausência de genotoxicidade de THI, dose-, tempo- e sexo-independente, e moderada toxicidade sistêmica dose-independente, mas tempo- e sexo-dependente. A associação do THI e DXR também sugere efeitos antigenotóxicos. Por conseguinte, THI pode reduzir os efeitos genotóxicos induzidos pelo quimioterapêutico.
Asunto(s)
Animales , Ratones , Daño del ADN/efectos de los fármacos , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Extractos Vegetales/farmacología , Doxorrubicina/toxicidad , Sustancias Protectoras/farmacología , Pruebas de Micronúcleos , Células Cultivadas , Tabebuia/químicaRESUMEN
Handroanthus impetiginosus has long been used in traditional medicine and various studies have determined the presence of bioactive chemical compounds and potential phytotherapeutics. In this study, the genotoxicity of the lyophilized tincture of H. impetiginosus bark (THI) was evaluated in mouse bone marrow using micronucleus assays. The interaction between THI and genotoxic effects induced by the chemotherapeutic agent, doxorubicin (DXR), was also analyzed. Experimental groups were evaluated 24 to 48 h after treatment with N-nitroso-N-ethylurea (NEU; 50 mg/kg), DXR (5 mg/kg), sodium chloride (NaCl; 150 mM), and THI (0.5-2 g/kg). Antigenotoxic assays were carried out using THI (0.5 g/kg) in combination with NEU or DXR. Analysis of the micronucleated polychromatic erythrocytes (MNPCEs) indicated no significant differences between treatment doses of THI (0.5-2 g/kg) and NaCl. Polychromatic erythrocyte (PCE) to normochromatic erythrocyte (NCE) ratios did not indicate any statistical differences between DXR and THI or NaCl, but there were differences between THI and NaCl. A significant reduction in MNPCEs and PCE/NCE ratios was observed when THI was administered in combination with DXR. This study suggested the absence of THI genotoxicity that was dose-, time-, and gender-independent and the presence of moderate systemic toxicity that was dose-independent, but time- and gender-dependent. The combination of THI and DXR also suggested antigenotoxic effects, indicating that THI reduced genotoxic effects induced by chemotherapeutic agents.
Asunto(s)
Células de la Médula Ósea , Daño del ADN/efectos de los fármacos , Doxorrubicina/toxicidad , Extractos Vegetales/farmacología , Sustancias Protectoras/farmacología , Tabebuia/química , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Células Cultivadas , Ratones , Pruebas de MicronúcleosRESUMEN
Abstract This study evaluated the genotoxicity of lyophilized glycolic extract of Theobroma cacao Linné seeds (TCL), using the micronucleus assay in bone marrow of mice. The interaction between TCL and doxorubicin (DXR) was also analyzed. Experimental groups were evaluated 24-48 h after treatment with N-Nitroso-N-ethylurea (NEU: 50 mg/kg), DXR (5 mg/kg), NaCl (145 mM), TCL (0.5-2 g/kg), and TCL (2 g/kg) in combination with DXR (antigenotoxic assays). Analysis of micronucleated polychromatic erythrocytes (MNPCEs) showed no significant differences between all the treatment doses of TCL and NaCl control. Mice experimentally treated with DXR and NEU significantly induced MNPCEs. However, a significant reduction of MNPCEs was also observed when TCL was administered in combination with the chemotherapeutic agent DXR. The analysis of the PCE/NCE ratio revealed no significant differences between the NaCl control, all doses of TCL, and DXR. However, there were significant differences in the PCE/NCE ratio between positive NEU control and all other treatments. The PCE/NCE ratio observed after treatment with TCL and DXR showed significant differences and intermediate values to controls (NaCl and NEU). This study suggests absence of genotoxicity and cytotoxicity of TCL, regardless of dose, sex, and time. TCL reduced genotoxic effects induced by DXR, suggesting potential antigenotoxic effects.
Resumo Este estudo avaliou a genotoxicidade do extrato glicólico liofilizado de sementes de Theobroma cacao Linné (TCL), usando o ensaio do micronúcleo em medula óssea de camundongos. A interação entre TCL e doxorrubicina (DXR) foi também analisada. Grupos experimentais foram avaliados 24-48 h após tratamento com N-Nitroso-N-etilureia (NEU: 50 mg/kg), DXR (5 mg/kg), NaCl (145 mM), TCL (0,5-2 g/kg), e TCL (2 g/kg) em combinação com DXR (ensaio antigenotóxico). As análises de eritrócitos policromáticos micronucleados (EPCMNs) não mostraram diferenças significantes entre todas as doses de tratamento do TCL e o controle NaCl. Camundongos experimentalmente tratados com DXR e NEU induziram significativamente EPCMNs. Contudo, uma redução significante de EPCMNs foi também observada quando TCL foi administrada em combinação com o agente quimioterapêutico DXR. As análises da relação EPC/ENC (eritrócito policromático/eritrócito normocromático) revelaram ausência de diferenças significantes entre o controle NaCl, todas as doses de TCL e DXR. Contudo, houve diferenças significantes na relação EPC/ENC entre o controle positivo NEU e todos os outros tratamento. A relação ECP/ENC observada após o tratamento com TCL e DXR mostrou diferenças significantes e valores intermediários aos controles (NaCl e NEU). Este estudo sugere ausência de genotoxicidade e citotoxicidade de TCL, independentemente da dose, sexo e tempo. TCL reduziu os efeitos genotóxicos induzidos por DXR, sugerindo potencial efeitos antigenotóxicos.
RESUMEN
AIM: This study aimed to investigate the efficiency of Magnitude Squared Coherence (MSC) and Spectral F test (SFT) for the detection of auditory steady state responses (ASSR) obtained by amplitude-modulated noises. MATERIAL AND METHODS: Twenty individuals (12 women) without any history of neurological or audiological diseases, aged from 18 to 59 years (mean ± standard deviation = 26.45 ± 3.9 years), who provided written informed consent, participated in the study. The Audiostim system was used for stimulating and ASSR recording. The tested stimuli were amplitude-modulated Wide-band noise (WBN), Low-band noise (LBN), High-band noise (HBN), Two-band noise (TBN) between 77 and 110 Hz, applied in intensity levels of 55, 45, and 25 dB sound pressure level (SPL). MSC and SFT, two statistical-based detection techniques, were applied with a significance level of 5%. Detection times and rates were compared using the Friedman test and Tukey-Kramer as post hoc analysis. Also based on the stimulation parameters (stimuli types and intensity levels) and detection techniques (MSC or SFT), 16 different pass/fail protocols, for which the true negatives (TN) were calculated. RESULTS: The median detection times ranged from 68 to 157s for 55 dB SPL, 68-99s for 45 dB SPL, and 84-118s for 25 dB SPL. No statistical difference was found between MSC and STF considering the median detection times (p > 0.05). The detection rates ranged from 100% to 55.6% in 55 dB SPL, 97.2%-38.9% in 45 dB SPL and 66.7%-8.3% in 25 dB SPL. Also for detection rates, no statistical difference was observed between MSC and STF (p > 0.05). True negatives (TN) above 90% were found for Protocols that employed WBN or HBN, at 55 dB SPL or that used WBN or HBN, at 45 dB SPL. For Protocols employing TBN, at 55 dB SPL or 45 dB SPL TN below 60% were found due to the low detection rates of stimuli that included low-band frequencies. CONCLUSION: The stimuli that include high-frequency content showed higher detection rates (>90%) and lower detection times (<3 min). The noise composed by two bands applied separately (TBN) is not feasible for clinical applications since it requires prolonging the exam duration, and also led to a reduced percentage of true negatives. On the other hand, WBN and HBN achieved high detection performance and high TN and should be investigated to implement pass/fail protocol for hearing screening with clinical population. Finally, both WBN and HBN seemed to be indifferent to the employed technique (SFT or MSC), which can be seen as another advantage of ASSR employment.
Asunto(s)
Estimulación Acústica/métodos , Umbral Auditivo/fisiología , Potenciales Evocados Auditivos/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Ruido , Adulto JovenRESUMEN
Objetivou-se avaliar o efeito de combinações de diferentes fontes de nitrogênio não proteico com fontes de carboidratos como suplemento para bovinos sobre o consumo, degradabilidade in situ, taxa de passagem e cinética ruminal em bovinos. Os tratamentos consistiram nos seguintes suplementos proteinados: CSUENC = casca de soja + ureia encapsulada; CSUREIA = casca de soja + ureia; MTAMIR = milho triturado + amireia; MTURENC = milho triturado + ureia encapsulada, MTUREIA = milho triturado + ureia. Os animais foram alimentados com feno de Brachiaria brizantha cv. Marandu como fonte de volumoso. O ensaio foi conduzido em delineamento quadrado latino 5x5 (cinco suplementos, cinco animais, cinco períodos). Não houve diferenças para consumo de nutrientes (P>0,05), exceto para consumo de proteína bruta g/kgPV0,75, em que se verificou maior consumo no tratamento CSUENC. Para frações fibrosas, foram obtidas maiores ingestões de fibra em detergente neutro, fibra em detergente ácido (kg/dia; % PV; g/kgPV0,75), hemicelulose (% PV; g/kgPV0,75) quando alimentados com CSUREIA em relação àqueles com MTUREIA (P<0,05). Os tratamentos constituídos pelos diferentes proteinados não afetaram a degradabilidade in situ das frações nutricionais (P>0,05), exceto para fração potencialmente degradável da celulose. A concentração de nitrogênio amoniacal no líquido ruminal foi influenciada pela composição dos proteinados (P<0,05), sendo superior para os tratamentos MTUREIA e MTURENC em relação à CSURENC. As combinações entre diferentes fontes de nitrogênio não proteico e de carboidratos nos diferentes suplementos não modificam o consumo e a degradabilidade da forragem. Dessa forma, a escolha dos ingredientes para formulação de proteinados deve ser realizada considerando-se disponibilidade e preços desses suplementos.(AU)
The aim of this study was to evaluate the effect of combinations of different sources of non-protein nitrogen with carbohydrate sources as supplement feed to cattle on intake, in situ degradability and passage rate. Treatments consisted of the following protein supplements: CSUENC= soybean hulls + encapsulated urea; CSUREIA = soybean hulls + urea; MTAMIR = ground corn + starea; MTURENC = ground corn + encapsulated urea; MTUREIA = ground corn + urea. The animals were fed with Brachiaria brizantha cv. Marandu as roughage. The experiment was conducted in a latin square design (five supplements, five animals, five periods). The treatments did not affect the intake of nutrients (P>0.05), although a higher intake of crude protein (g/kgBW0.75) was observed by animals fed with CSUENC. A higher intake of NDF, ADF (kg/day, %BW; g/kgBW0.75) and hemicellulose (% PV; g/kgBW0.75) was observed by animals fed with CSUREIA when compared to those with MTUREIA (P<0.05). The degradability of nutritional fractions was not affected by any of the treatments (P>0.05), except for the potentially degradable cellulose. The ammoniacal nitrogen concentration in rumen fluid was influenced by the protein source (P<0.05) and was higher for MTUREIA and MTURENC treatments in relation to CSURENC. The tested combinations of different sources of non-protein nitrogen with different carbohydrates did not affect the forage intake or degradability. Therefore, the choice of the ingredients for protein supplement formulation should be made considering other factors as availability and price of these supplements.(AU)
Asunto(s)
Animales , Bovinos , Rumen/metabolismo , Proteínas en la Dieta/administración & dosificación , Cinética , Suplementos Dietéticos/análisis , Digestión/fisiologíaRESUMEN
AIMS: Dinoponera quadriceps venom (DqV) was examined to evaluate the antibacterial activity and its bactericidal action mechanism against Staphylococcus aureus. METHODS AND RESULTS: DqV was tested against a standard strain of methicillin-sensitive Staphylococcus aureus (MSSA), Staph. aureus ATCC 6538P and two standard strains of methicillin-resistant Staphylococcus aureus (MRSA), Staph. aureus ATCC 33591 and Staph. aureus CCBH 5330. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), the rate of kill and pH sensitivity of the DqV were determined by microdilution tests. Bactericidal and inhibitory concentrations of DqV were tested to check its action on Staph. aureus membrane permeability and cell morphology. The MIC and MBC of DqV were 6·25 and 12·5 µg ml(-1) for Staph. aureus ATCC 6538P, 12·5 and 50 µg ml(-1) for Staph. aureus CCBH 5330 and 100 and 100 µg ml(-1) for Staph. aureus ATCC 33591, respectively. Complete bacterial growth inhibition was observed after 4 h of incubation with the MBC of DqV. A lowest MIC was observed in alkaline pH. Alteration in membrane permeability was observed through the increase in crystal violet uptake, genetic material release and morphology in atomic force microscopy. CONCLUSIONS: The results suggest antibacterial activity of DqV against Staph. aureus and that the venom acts in the cell membrane. SIGNIFICANCE AND IMPACT OF THE STUDY: Alteration in membrane permeability may be associated with the antimicrobial activity of hymenopteran venoms.
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Venenos de Hormiga/farmacología , Antibacterianos/farmacología , Staphylococcus aureus/efectos de los fármacos , Animales , HormigasRESUMEN
The stink bug Dichelops melacanthus (Dallas) has become one of the major pests of corn and wheat in Brasil, mainly after a shift from the conventional tillage system to the no tillage cultivation system. This fact may be due to the simultaneous occurrence of second planting corn with wheat cultivation, and the presence of wild hosts. This study aimed to evaluate the population dynamics of D. melacanthus on wild hosts adjacent to areas cultivated with corn, wheat, and soybean during the season and off-season of soybean cultivation. Weekly surveys were conducted in the region of Londrina, PR, Brasil from the beginning of July 2007 up to the end of June 2008 using the square meter method. Corn (Zea mays), soybean (Glycine max), tropical spiderwort (Commelina benghalensis), hairy indigo (Indigofera hirsuta), crotalaria (Crotalaria pallida), wheat (Triticum aestivum), and signal grass (Brachiaria decumbens) were identified as hosts of D. melacanthus. Signal grass was the host in which stink bug adults were found in higher numbers, while nymphs and adults were consistently collected on tropical spiderwort. Although nymphs completed their development on tropical spiderwort seeds, this host was found less suitable than soybean seeds.
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Glycine max/parasitología , Heterópteros/fisiología , Triticum/parasitología , Zea mays/parasitología , Animales , Femenino , Masculino , Dinámica PoblacionalRESUMEN
Greenhouse and laboratory studies were conducted to evaluate feeding activity and superficial damage to soybean seed by the brown-winged stink bug, Edessa meditabunda (F.), and the Neotropical brown stink bug, Euschistus heros (F.). Soybean plants (cv. BRS 282), at R6 stage of development were used. Thirty pairs of each species were used individually for 48 h. Two daily observations (9:00 AM and 3:00 PM) were taken to record the number of bugs (feeding/resting) on plant parts. Harvested seeds imbibed in tetrazolium solution were photographed for measurement of the damaged surface. Adult E. meditabunda significantly preferred soybean stems (19.7 bugs) to pods (2.7). Feeding/resting was similar at 9:00 AM (mean number of 28.0 bugs) and 3:00 PM (24.3). Euschistus heros equally fed/stayed on stems (7.3 bugs) and pods (6.9), although most bugs (12.3) remained on the cage net; feeding/resting on all plant structures amounted to 13.7 bugs at 9:00 AM and 17.7 bugs at 3:00 PM. Amylase activity was greater for E. heros (41.61 ± 0.89 U/mg) and almost none for E. meditabunda (2.35 ± 0.14 U/mg). The superficial damage to seeds was significantly greater for E. meditabunda (22. 9 mm(2)) compared to E. heros (12.5 mm(2)). However, E. meditabunda caused less shrinkage of the seed tegument, while E. heros damage was deeper and seeds showed reduction in size.
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Amilasas/metabolismo , Conducta Alimentaria , Glycine max/parasitología , Hemípteros/fisiología , Saliva/enzimología , Semillas/parasitología , Animales , HeterópterosRESUMEN
Limited information exists on the insecticide susceptibility of redbanded stink bug, Piezodorus guildinii (Westwood) (Heteroptera: Pentatomidae), despite its impact on soybean, Glycine max (L.) Merr., production in Brazil and the United States. Therefore, this study set out to 1) determine baseline levels of susceptibility to currently recommended pesticides using topical and vial bioassays, 2) determine the levels of esterase activity in populations in the United States and Brazil, and 3) compare control among products in field trials. In topical bioassays conducted in the United States using technical grade materials, the LC50 values of lambda-cyhalothrin, acephate, and methamidophos were 4-25, 141-295, and 40-151 ng per insect, respectively. The LC50 values of imidacloprid and thiamethoxam were 11 and 27 ng per insect, respectively. In vial bioassays conducted in the United States using technical grade materials, the LC50 values of cypermethrin, acephate, and methamidophos were 0.4-0.9, 3.8, and 1.6 microg per vial, respectively. In topical bioassays conducted in Brazil by using commercially formulated products, the LC50 values of acephate, methamidophos, endosulfan, and imidacloprid were 0.90-1.9, 0.4-0.6, 1.5-6.6, and 0.2-0.3 microg per insect, respectively. In vial bioassays conducted in Brazil using commercially formulated products, the LC50 values of endosulfan, methamidophos, and lambda-cyhalothrin were 4-32 and 2-24 microg/cm2 for thiamethoxam and imidacloprid. Esterase activity in Louisiana (United States) populations ranged from 251 to 658 nmol alpha-naphthol formed/min/mg protein. Esterase activity levels in Londrina (Brazil) populations averaged 163 nmol/min/mg. In field tests, P. guildinii in Louisiana were controlled by organophosphates thiamethoxam and imidacloprid and in Brazil, with combinations of neonicotinoids and pyrethroids.
Asunto(s)
Esterasas/metabolismo , Heterópteros , Insecticidas , Animales , Brasil , Heterópteros/enzimología , LouisianaRESUMEN
INTRODUCTION: Parkinson's disease (PD) is associated with mood and behavioral symptoms contributing to morbidity and reduced quality of life of the patients. Most characteristic are depression, anxiety and impulse control disorder. DEVELOPMENT: Identification and treatment of neuropsychiatric symptoms is necessary for an appropriate management of PD. Affective symptoms may be the initial manifestation of PD, are highly prevalent and pathogenically complex. Impulse control disorders are usually not a spontaneous complaint, so asking about these symptoms may be the only way to detect and treat a serious socio-familial problem. Pharmacological treatment of these manifestations is difficult to balance with an adequate control of motor symptoms. Psychological support from early stages and throughout the evolution of PD is fundamental. CONCLUSIONS: Neurologist and other healthcare professionals treating PD patients need to be aware of behavioral and emotional manifestations of the disease. This will lead to an appropriate patient management and better adaptation of the familial and social situation.
Asunto(s)
Síntomas Afectivos/etiología , Trastornos Disruptivos, del Control de Impulso y de la Conducta/etiología , Trastornos Disruptivos, del Control de Impulso y de la Conducta/fisiopatología , Trastornos del Humor/etiología , Trastornos del Humor/fisiopatología , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/fisiopatología , Síntomas Afectivos/tratamiento farmacológico , Síntomas Afectivos/fisiopatología , Antiparkinsonianos/uso terapéutico , Ansiedad/tratamiento farmacológico , Ansiedad/etiología , Ansiedad/fisiopatología , Depresión/tratamiento farmacológico , Depresión/etiología , Depresión/fisiopatología , Trastornos Disruptivos, del Control de Impulso y de la Conducta/tratamiento farmacológico , Emociones/fisiología , Humanos , Trastornos del Humor/tratamiento farmacológico , Enfermedad de Parkinson/tratamiento farmacológico , Calidad de VidaRESUMEN
INTRODUCTION: Patients with Parkinson's disease (PD) may present neuropsychiatric and conduct disorders at different stages of the development of the disease that make treatment even more difficult. DEVELOPMENT: The neurologist must be on the lookout for the possible appearance of alterations affecting impulse control, even from the early stages of the disease, so as to be able to prevent them or to plan a suitable adjustment of treatment. Some of the most common impulsivity disorders include hypersexuality, compulsive gambling and other addictive behaviours which, if left undetected and untreated, can end up having a destructive effect on the patient's socio-familial surroundings. Psychotic disorders (hallucinations, delusions) are often associated to advanced phases of PD and to the effect of dopamine therapy, and they are associated to a higher morbidity and mortality rate. Factors of a genetic or pharmacogenetic nature or a gene-environment interaction may account for the different individual susceptibility to disorders in the neuropsychiatric realm among patients with PD. It is wise to bear in mind the possible medico-legal implications that may stem from behavioral disorders, both for the patient and his or her family and for the physician, because situations could arise that trigger conflicts between confidentiality and preventing third parties from being harmed, as well as harm that can be attributed to the side effects of medicines. CONCLUSIONS: The specialist must be familiar with, foresee and propose suitable treatment for behavioral and neuropsychiatric disorders in PD with potential medico-legal implications.
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Trastornos Mentales/etiología , Trastornos Mentales/genética , Trastornos Mentales/fisiopatología , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/fisiopatología , Confidencialidad , Progresión de la Enfermedad , Dopaminérgicos/uso terapéutico , Humanos , Responsabilidad Legal , Trastornos Mentales/tratamiento farmacológico , Enfermedad de Parkinson/tratamiento farmacológico , LinajeRESUMEN
Resumen. Introducción. Los pacientes con enfermedad de Parkinson (EP) pueden presentar alteraciones neuropsiquiátricas y del comportamiento en diferentes estadios evolutivos de la enfermedad que dificulten el tratamiento. Desarrollo. Es necesario que el neurólogo esté atento a la posible aparición de alteraciones en el control de los impulsos, incluso desde fases tempranas de la enfermedad, para poder prevenirlas o planificar un ajuste adecuado del tratamiento. Entre los trastornos de impulsividad más comunes están la hipersexualidad, la ludopatía y otras conductas adictivas que, si no se detectan y tratan, pueden resultar destructivas para el entorno sociofamiliar del paciente. Los trastornos de la esfera psicótica (alucinaciones, ideas delirantes) a menudo están asociados a fases avanzadas de la EP y al efecto del tratamiento dopaminérgico, y se asocian con una mayor morbimortalidad. Es posible que factores genéticos, farmacogenéticos o una interacción gen-ambiente expliquen la diferente susceptibilidad individual a alteraciones en la esfera neuropsiquiátrica entre los pacientes con EP. Es conveniente recordar las posibles implicaciones médico-legales que pueden tener los trastornos de la conducta, tanto para el paciente y su familia como para el médico, pues se podrían plantear conflictos entre la confidencialidad y la prevención de daños a terceros, así como daño atribuible al efecto secundario de medicamentos. Conclusiones. Se debe conocer, prever y tratar adecuadamente las alteraciones de la conducta y neuropsiquiátricas en la EP, con implicaciones médicas y legales (AU)
Summary. Introduction. Patients with Parkinsons disease (PD) may present neuropsychiatric and conduct disorders at different stages of the development of the disease that make treatment even more difficult. Development. The neurologist must be on the lookout for the possible appearance of alterations affecting impulse control, even from the early stages of the disease, so as to be able to prevent them or to plan a suitable adjustment of treatment. Some of the most common impulsivity disorders include hypersexuality, compulsive gambling and other addictive behaviours which, if left undetected and untreated, can end up having a destructive effect on the patients socio-familial surroundings. Psychotic disorders (hallucinations, delusions) are often associated to advanced phases of PD and to the effect of dopamine therapy, and they are associated to a higher morbidity and mortality rate. Factors of a genetic or pharmacogenetic nature or a gene-environment interaction may account for the different individual susceptibility to disorders in the neuropsychiatric realm among patients with PD. It is wise to bear in mind the possible medico-legal implications that may stem from behavioral disorders, both for the patient and his or her family and for the physician, because situations could arise that trigger conflicts between confidentiality and preventing third parties from being harmed, as well as harm that can be attributed to the side effects of medicines. Conclusions. The specialist must be familiar with, foresee and propose suitable treatment for behavioral and neuropsychiatric disorders in PD with potential medico-legal implications (AU)
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Humanos , Enfermedad de Parkinson/complicaciones , Trastornos Mentales/epidemiología , Predisposición Genética a la Enfermedad , Trastornos Disruptivos, del Control de Impulso y de la Conducta/epidemiología , Trastornos Psicóticos/epidemiología , Trastorno Obsesivo Compulsivo/epidemiologíaRESUMEN
BACKGROUND AND PURPOSE: Many compounds liberating NO (NO donors) have been used as therapeutic agents. Here we test two ruthenium nitrosyls, which release NO when activated by biological reducing agents, for their effects in vitro and in vivo against Trypanosoma cruzi, the agent responsible for the American trypanosomiasis (Chagas' disease). EXPERIMENTAL APPROACH: Ruthenium NO donors were incubated with a partially drug-resistant strain of T. cruzi and the anti-proliferative and trypanocidal activities evaluated. In a mouse model of acute Chagas' disease, trypanocidal activity was evaluated by measuring parasitemia, survival rate of infected mice and elimination of amastigotes in myocardial tissue. KEY RESULTS: In vitro, the observed anti-proliferative and trypanocidal activities of trans-[Ru(NO)(NH(3))(4)isn](BF(4))(3) and trans-[Ru(NO)(NH(3))(4)imN](BF(4))(3) were due to NO liberated upon reduction of these nitrosyls. Ru(NO)isn had a lower IC(50 epi) (67 microM) than the NO donor, sodium nitroprusside (IC(50 epi)=244 microM) and Ru(NO)imN (IC(50 try)=52 microM) was more potent than gentian violet (IC(50 try)=536 microM), currently used in the treatment of blood. Both ruthenium nitrosyls eliminated, in vivo, extracellular as well as intracellular forms of T. cruzi in the bloodstream and myocardial tissue and allowed survival of up to 80% of infected mice at a dose (100 nmol kg(-1) day(-1)) much lower than the optimal dose for benznidazole (385 micromol kg(-1) day(-1)). CONCLUSIONS AND IMPLICATIONS: Our data strongly suggest that NO liberated is responsible for the anti-proliferative and trypanocidal activities of the ruthenium NO donors and that these compounds are promising leads for novel and effective anti-parasitic drugs.
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Enfermedad de Chagas/tratamiento farmacológico , Corazón/efectos de los fármacos , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico/metabolismo , Parasitemia/tratamiento farmacológico , Compuestos de Rutenio/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Enfermedad de Chagas/metabolismo , Enfermedad de Chagas/patología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Violeta de Genciana/farmacología , Corazón/parasitología , Concentración 50 Inhibidora , Ratones , Miocardio/patología , Donantes de Óxido Nítrico/metabolismo , Donantes de Óxido Nítrico/uso terapéutico , Nitroprusiato/farmacología , Parasitemia/metabolismo , Parasitemia/parasitología , Parasitemia/patología , Pruebas de Sensibilidad Parasitaria , Compuestos de Rutenio/metabolismo , Compuestos de Rutenio/uso terapéutico , Tripanocidas/metabolismo , Tripanocidas/uso terapéutico , Trypanosoma cruzi/crecimiento & desarrolloRESUMEN
The nitrile ligands in the platinum(IV) complexes trans-[PtCl4(RCN)2] (R=Me, Et, CH2Ph) and cis/trans-[PtCl4(MeCN)(Me2SO)] are involved in a metalla-Pinner reaction with N-methylbenzohydroxamic acid (N-alkylated form of hydroxamic acid, hydroxamic form; F1), PhC(=O)N(Me)OH, to achieve the imino species [PtCl4[NH=C(R)ON(Me)C(=O)Ph]2 (1-3) and [PtCl4[NH=C(Me)ON(Me)C(=O)Ph](Me2SO)] (7), respectively. Treatment of trans-[PtCl4(RCN)2] (R=Me, Et) and cis/trans-[PtCl4(MeCN)(Me2SO)] with the O-alkylated form of a hydroxamic acid (hydroximic form), i.e. methyl 2,4,6-trimethylbenzohydroximate, 2,4,6-(Me3C6H2)C(OMe)=NOH (F2A), allows the isolation of [PtCl4[NH=C(R)ON=C(OMe)(2,4,6-Me3C6H2)]2] (5, 6) and [PtCl4[NH=C(Me)ON=C(OMe)(2,4,6-Me3C6H2)](Me2SO)] (8), correspondingly. In accord with the latter reaction, the coupling of nitriles in trans-[PtCl4(EtCN)2] with methyl benzohydroximate, PhC(OMe)=NOH (F2B), gives [PtCl4[NH=C(Et)ON=C(OMe)Ph]2] (4). The addition proceeds faster with the hydroximic F2, rather than with the hydroxamic form F1. The complexes 1-8 were characterized by C, H, N elemental analyses, FAB+ mass-spectrometry, IR, 1H and 13C[1H] NMR spectroscopies. The X-ray structure determinations have been performed for both hydroxamic and hydroximic complexes, i.e. 2 and 6, indicating that the imino ligands are mutually trans and they are in the E-configuration.