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This study aimed to prepare an inventory of the main active ingredients of pesticides and estimate the risk of pollution of groundwater and surface water resources in a Brazilian semiarid basin. The inventory was prepared using data from government agency databases. The contamination risk estimate was obtained using the GOSS index, Groundwater Ubiquity Score (GUS), Groundwater Screening Index (GSI), Leachability Index (LIX), US Environmental Protection Agency (USEPA) criteria, Leaching Index (LEACH), and Relative Leaching Potential Index (RLPI). The inventory identified 57 active ingredients commercialized under a well-defined chemical class. Most of these (51.5%) belong to the very dangerous class, while 43.6% belong to the moderately toxic class. The GOSS model showed that 23.7% of the active ingredients have a low potential, 50.85% have a moderate potential, and 13.56% have a high potential for surface water contamination, with its transport being associated with the sediment. The GUS index indicates a low potential for groundwater contamination. However, the GSI points to a high potential for water contamination, the USEPA criteria for a possible contamination of groundwater, and, according to the LIX, most of the pollutants do so by leaching. The information provided contributes to the management of xenobiotic compounds in arid and semiarid basins, adding to the water security effort by providing tools for the assessment of potential pesticide pollution. Integr Environ Assess Manag 2023;19:804-816. © 2022 SETAC.
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Água Subterrânea , Praguicidas , Poluentes Químicos da Água , Praguicidas/análise , Água , Brasil , Poluentes Químicos da Água/análise , Água Subterrânea/química , Monitoramento Ambiental , Poluição da ÁguaRESUMO
Computational simulation of colloidal systems make use of empirical interaction potentials that are founded in well-established theory. In this work, we have performed parallel tempering Monte Carlo (PTMC) simulations to calculate heat capacity and to assess structural transitions, which may occur in charged colloidal clusters whose effective interactions are described by a sum of pair potentials with attractive short-range and repulsive long-range components. Previous studies on these systems have shown that the global minimum structure varies from spherical-type shapes for small-size clusters to Bernal spiral and "beaded-necklace" shapes at intermediate and larger sizes, respectively. In order to study both structural transitions and dissociation, we have organized the structures appearing in the PTMC calculations by three sets according to their energy: (i) low-energy structures, including the global minimum; (ii) intermediate-energy "beaded-necklace" motifs; (iii) high-energy linear and branched structures that characterize the dissociative clusters. We observe that, depending on the cluster, either peaks or shoulders on the heat-capacity curve constitute thermodynamics signatures of dissociation and structural transitions. The dissociation occurs at T=0.20 for all studied clusters and it is characterized by the appearance of a significant number of linear structures, while the structural transitions corresponding to unrolling the Bernal spiral are quite dependent on the size of the colloidal system.
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The microsolvation of Li+ by both argon and krypton atoms has been studied based on a new potential energy surface that includes two- and three-body interactions; the potential terms involving the lithium ion were calibrated with CCSD(T)/aug-cc-pVQZ energies after being corrected for the basis-set superposition error. The structures of the Li+Ar nKr m ([Formula: see text]) clusters arising from global optimization show a first solvation shell preferentially occupied by krypton atoms. These binary-solvent microsolvation clusters are most stable when the total number of krypton (argon) atoms occupy the first (second) solvation shell.
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Correction for 'Solvation of Li+ by argon: how important are three-body forces?' by Frederico V. Prudente et al., Phys. Chem. Chem. Phys., 2017, 19, 25707-25716.
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The PR-1 proteins (pathogenesis-related protein 1) are involved in plant defense mechanisms against various pathogens. The genome of cacao (Theobroma cacao) encodes 14 PR-1 proteins, named TcPR-1a to TcPR-1n. Two of them, TcPR-1f and TcPR-1g, have a C-terminal expansion with high similarity to protein kinase domains, suggesting a receptor-like kinase (RLK) protein architecture. Moreover, TcPR-1g is highly expressed during cacao response to Witches' Broom Disease, caused by the fungus Moniliopthora perniciosa. Here we describe a structural genomics approach to clone, express and purify the kinase domains of TcPR-1f and TcPR-1g. Escherichia coli BL21(DE3)-R3 cells were used for protein expression and co-expression of Lambda Protein Phosphatase was critical for successfully obtaining soluble recombinant protein. We expect that the ability to express and purify the kinase domains of TcPR-1f and TcPR-1g will further our understanding of the role these proteins play during cacao defense response.
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Cacau/genética , Clonagem Molecular/métodos , Proteínas de Plantas/genética , Sequência de Aminoácidos , Cacau/química , Escherichia coli/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/química , Domínios Proteicos , Proteínas Quinases/química , Proteínas Quinases/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Alinhamento de SequênciaRESUMO
A new analytical potential for Li+Ar2 including three-body interactions has been modeled by employing ab initio energies that were calculated within the CCSD(T) framework and a quadruple-zeta basis-set (i.e., cc-pVQZ for lithium and aug-cc-pVQZ for argon) and, then, corrected for the basis-set superposition error (BSSE) with the counterpoise method. Departing from this function, we have constructed the potential energy surface for Li+Arn clusters by summing over all two-body and three-body terms. We have employed our evolutionary algorithm (EA) to perform a global geometry optimization that allows for the study of a Li+ ion microsolvated with argon atoms. For the smaller clusters, the putative global minimum geometry obtained for the analytical potential has been used as a starting point for an ab initio optimization at the MP2 level. For clusters up to n = 10, the energetics and structures from the analytical potential energy surface (PES) that includes three-body interactions show good agreement with the corresponding ones optimized at the ab initio level. Removing the three-body terms from the analytical PES leads to global minima that fail to represent the main energetic features and the structures become wrong in the case of the Li+Ar2, Li+Ar3 and Li+Ar10 clusters. For n > 10, the comparison between potentials with and without three-body forces shows significant structural and energetic differences for most of the cluster sizes.
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The pathogenic fungi Moniliophthora perniciosa causes Witches' Broom Disease (WBD) of cacao. The structure of MpPR-1i, a protein expressed by M. perniciosa when it infects cacao, are presented. This is the first reported de novo structure determined by single-wavelength anomalous dispersion phasing upon soaking with selenourea. Each monomer has flexible loop regions linking the core alpha-beta-alpha sandwich topology that comprise ~50% of the structure, making it difficult to generate an accurate homology model of the protein. MpPR-1i is monomeric in solution but is packed as a high ~70% solvent content, crystallographic heptamer. The greatest conformational flexibility between monomers is found in loops exposed to the solvent channel that connect the two longest strands. MpPR-1i lacks the conserved CAP tetrad and is incapable of binding divalent cations. MpPR-1i has the ability to bind lipids, which may have roles in its infection of cacao. These lipids likely bind in the palmitate binding cavity as observed in tablysin-15, since MpPR-1i binds palmitate with comparable affinity as tablysin-15. Further studies are required to clarify the possible roles and underlying mechanisms of neutral lipid binding, as well as their effects on the pathogenesis of M. perniciosa so as to develop new interventions for WBD.
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Agaricales/metabolismo , Cacau/microbiologia , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Agaricales/química , Sítios de Ligação , Cristalografia por Raios X , Modelos Moleculares , Palmitatos/metabolismo , Doenças das Plantas/microbiologia , Ligação Proteica , Conformação ProteicaRESUMO
Pneumococcal surface protein A (PspA) is a candidate antigen for the composition of protein-based vaccines against Streptococcus pneumoniae. While searching for efficient adjuvants for PspA-based vaccines, our group has described the potential of combining PspA with the whole-cell pertussis vaccine (wP). When given to mice through the nasal route, a formulation composed of PspA from clade 5 (PspA5) and wP (PspA5-wP) induced high levels of antibodies and protection against challenges with different pneumococcal strains. PspA5-wP also induced the secretion of interleukin 17 (IL-17) by splenocytes and the infiltration of leukocytes in the lungs after challenge. Here, we show that protection against a pneumococcal invasive challenge was completely abrogated in µMT(-/-) mice, which are deficient in the maturation of B cells, illustrating the importance of antibodies in the survival elicited by the PspA5-wP vaccine. Moreover, passive immunization showed that IgG purified from the sera of mice immunized with PspA5-wP conferred significant protection to naive mice, whereas the respective F(ab')2 did not. Additionally, in vivo depletion of complement abolished protection against the pneumococcal challenge. The combination of PspA5 with wild-type or mutant Bordetella pertussis strains or with purified components showed that the pertussis toxin (PT)-containing formulations induced the highest levels of antibodies and protection. This suggests that the adjuvant activity of wP in the PspA5 model is mediated at least in part by PT. The sera from mice immunized with such formulations displayed high IgG binding and induction of complement deposition on the pneumococcal surface in vitro, which is consistent with the in vivo results.
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Proteínas de Bactérias/imunologia , Toxina Pertussis/imunologia , Infecções Pneumocócicas/imunologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Adjuvantes Imunológicos , Administração Intranasal , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Linfócitos B/imunologia , Bordetella pertussis/imunologia , Proteínas do Sistema Complemento/imunologia , Imunização Passiva , Imunoglobulina G/administração & dosagem , Imunoglobulina G/imunologia , Interleucina-17/metabolismo , Leucócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Vacina contra Coqueluche/imunologia , Infecções Pneumocócicas/prevenção & controle , Receptores Imunológicos/imunologia , Proteínas Recombinantes/imunologia , Vacinas Estreptocócicas/imunologia , VacinaçãoRESUMO
The widespread SCP/TAPS superfamily (SCP/Tpx-1/Ag5/PR-1/Sc7) has multiple biological functions, including roles in the immune response of plants and animals, development of male reproductive tract in mammals, venom activity in insects and reptiles and host invasion by parasitic worms. Plant Pathogenesis Related 1 (PR-1) proteins belong to this superfamily and have been characterized as markers of induced defense against pathogens. This work presents the characterization of eleven genes homologous to plant PR-1 genes, designated as MpPR-1, which were identified in the genome of Moniliophthora perniciosa, a basidiomycete fungus responsible for causing the devastating witches' broom disease in cacao. We describe gene structure, protein alignment and modeling analyses of the MpPR-1 family. Additionally, the expression profiles of MpPR-1 genes were assessed by qPCR in different stages throughout the fungal life cycle. A specific expression pattern was verified for each member of the MpPR-1 family in the conditions analyzed. Interestingly, some of them were highly and specifically expressed during the interaction of the fungus with cacao, suggesting a role for the MpPR-1 proteins in the infective process of this pathogen. Hypothetical functions assigned to members of the MpPR-1 family include neutralization of plant defenses, antimicrobial activity to avoid competitors and fruiting body physiology. This study provides strong evidence on the importance of PR-1-like genes for fungal virulence on plants.
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Agaricales/genética , Cacau/genética , Cacau/microbiologia , Proteínas Fúngicas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Agaricales/química , Agaricales/fisiologia , Sequência de Aminoácidos , Cacau/química , Proteínas Fúngicas/química , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Genes de Plantas , Interações Hospedeiro-Patógeno , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Plantas/química , Conformação ProteicaRESUMO
Streptococcus pneumoniae is a pathogen of great importance worldwide. We have previously described the efficacy of a nasal vaccine composed of the pneumococcal surface protein A and the whole-cell pertussis vaccine as an adjuvant against a pneumococcal invasive challenge in mice. Spread of bacteria to the bloodstream was probably prevented by the high levels of systemic antibodies induced by the vaccine, but bacteria were only cleared from the lungs 3 weeks later, indicating that local immune responses may contribute to survival. Here we show that a strict control of inflammatory responses in lungs of vaccinated mice occurs even in the presence of high numbers of pneumococci. This response was characterized by a sharp peak of neutrophils and lymphocytes with a simultaneous decrease in macrophages in the respiratory mucosa at 12 h postchallenge. Secretion of interleukin-6 (IL-6) and gamma interferon (IFN-γ) was reduced at 24 h postchallenge, and the induction of tumor necrosis factor alpha (TNF-α) secretion, observed in the first hours postchallenge, was completely abolished at 24 h. Before challenge and at 12 h postchallenge, vaccinated mice displayed higher numbers of CD4(+) T, CD8(+) T, and B lymphocytes in the lungs. However, protection still occurs in the absence of each of these cells during the challenge, indicating that other effectors may be related to the prevention of lung injuries in this model. High levels of mucosal anti-PspA antibodies were maintained in vaccinated mice during the challenge, suggesting an important role in protection.
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Proteínas de Bactérias/imunologia , Pulmão/imunologia , Pulmão/patologia , Vacinas Pneumocócicas/imunologia , Pneumonia Pneumocócica/imunologia , Pneumonia Pneumocócica/patologia , Streptococcus pneumoniae/imunologia , Administração Intranasal , Animais , Anticorpos Antibacterianos/sangue , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Imunofenotipagem , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Vacinas Pneumocócicas/administração & dosagem , Análise de Sobrevida , Fatores de TempoRESUMO
Pneumococcal surface protein C (PspC) is an important candidate for a cost-effective vaccine with broad coverage against pneumococcal diseases. Previous studies have shown that Streptococcus pneumoniae is able to bind to both human factor H (FH), an inhibitor of complement alternative pathway, and human secretory IgA (sIgA) via PspC. PspC was classified into 11 groups based on variations of the gene. In this work, we used three PspC fragments from different groups (PspC3, PspC5, and PspC8) to immunize mice for the production of antibodies. Immunization with PspC3 induced antibodies that recognized the majority of the clinical isolates as analyzed by Western blotting of whole-cell extracts and flow cytometry of intact bacteria, while anti-PspC5 antibodies showed cross-reactivity with the paralogue pneumococcal surface protein A (PspA), and anti-PspC8 antibodies reacted only with the PspC8-expressing strain. Most of the isolates tested showed strong binding to FH and weaker interaction with sIgA. Preincubation with anti-PspC3 and anti-PspC5 IgG led to some inhibition of binding of FH, and preincubation with anti-PspC3 partially inhibited sIgA binding in Western blotting. The analysis of intact bacteria through flow cytometry showed only a small decrease in FH binding after incubation of strain D39 with anti-PspC3 IgG, and one clinical isolate showed inhibition of sIgA binding by anti-PspC3 IgG. We conclude that although anti-PspC3 antibodies were able to recognize PspC variants from the majority of the strains tested, partial inhibition of FH and sIgA binding through anti-PspC3 antibodies in vitro could be observed for only a restricted number of isolates.
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Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/imunologia , Reações Cruzadas , Imunoglobulina A Secretora/imunologia , Streptococcus pneumoniae/imunologia , Animais , Anticorpos Antibacterianos/sangue , Western Blotting , Fator H do Complemento/antagonistas & inibidores , DNA Bacteriano/química , DNA Bacteriano/genética , Feminino , Citometria de Fluxo , Imunoglobulina A Secretora/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Análise de Sequência de DNARESUMO
PspA is an important candidate for a vaccine with serotype-independent immunity against pneumococcal infections. Based on sequence relatedness, PspA has been classified into three families comprising six clades. We have previously addressed the cross-reactivity of antibodies against PspA fragments containing the N-terminal and proline-rich regions of PspA from clades 1 to 5 (PspA1, PspA2, PspA3, PspA4, and PspA5) by Western blot analysis and reported that anti-PspA4 and anti-PspA5 were able to recognize pneumococci expressing PspA proteins from all of the clades analyzed. We have now analyzed the functional capacity of these antibodies to bind and to mediate complement deposition on intact bacteria in vitro. Our results show that both PspA4 and PspA5 elicit antibodies that are able to bind and to mediate complement deposition efficiently on pneumococcal strains bearing PspA proteins from clades 1 to 5. Moreover, mice immunized with PspA4 and PspA5 were protected against an intranasal lethal challenge with strains expressing PspA proteins from the two major families. PspA4 and PspA5 are thus able to induce antibodies with a high degree of cross-reactivity in vitro, which is reflected in cross-protection of mice. We have also analyzed the contribution of the nonproline (NonPro) block within the conserved proline-rich region to the reactivity of anti-PspA antibodies, and the results indicate that N-terminal alpha-helical region, the blocks of proline repeats, and the NonPro region can influence the degree of cross-reactivity of antibodies to PspA.
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Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/imunologia , Proteínas do Sistema Complemento/imunologia , Proteção Cruzada/imunologia , Proteínas de Choque Térmico/imunologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Animais , Proteínas de Bactérias/química , Reações Cruzadas/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Proteínas de Choque Térmico/química , Camundongos , Camundongos Endogâmicos BALB C , Streptococcus pneumoniae , VacinaçãoRESUMO
BACKGROUND: The basidiomycete fungus Moniliophthora perniciosa is the causal agent of Witches' Broom Disease (WBD) in cacao (Theobroma cacao). It is a hemibiotrophic pathogen that colonizes the apoplast of cacao's meristematic tissues as a biotrophic pathogen, switching to a saprotrophic lifestyle during later stages of infection. M. perniciosa, together with the related species M. roreri, are pathogens of aerial parts of the plant, an uncommon characteristic in the order Agaricales. A genome survey (1.9x coverage) of M. perniciosa was analyzed to evaluate the overall gene content of this phytopathogen. RESULTS: Genes encoding proteins involved in retrotransposition, reactive oxygen species (ROS) resistance, drug efflux transport and cell wall degradation were identified. The great number of genes encoding cytochrome P450 monooxygenases (1.15% of gene models) indicates that M. perniciosa has a great potential for detoxification, production of toxins and hormones; which may confer a high adaptive ability to the fungus. We have also discovered new genes encoding putative secreted polypeptides rich in cysteine, as well as genes related to methylotrophy and plant hormone biosynthesis (gibberellin and auxin). Analysis of gene families indicated that M. perniciosa have similar amounts of carboxylesterases and repertoires of plant cell wall degrading enzymes as other hemibiotrophic fungi. In addition, an approach for normalization of gene family data using incomplete genome data was developed and applied in M. perniciosa genome survey. CONCLUSION: This genome survey gives an overview of the M. perniciosa genome, and reveals that a significant portion is involved in stress adaptation and plant necrosis, two necessary characteristics for a hemibiotrophic fungus to fulfill its infection cycle. Our analysis provides new evidence revealing potential adaptive traits that may play major roles in the mechanisms of pathogenicity in the M. perniciosa/cacao pathosystem.
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Agaricales/genética , Cacau/microbiologia , Genoma Fúngico , Doenças das Plantas/microbiologia , Agaricales/patogenicidade , Análise por Conglomerados , DNA Fúngico/genética , Etiquetas de Sequências Expressas , Genes Fúngicos , Genômica , Modelos Genéticos , Família Multigênica , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
Moniliophthora perniciosa is a hemibiotrophic fungus that causes witches' broom disease (WBD) in cacao. Marked dimorphism characterizes this fungus, showing a monokaryotic or biotrophic phase that causes disease symptoms and a later dikaryotic or saprotrophic phase. A combined strategy of DNA microarray, expressed sequence tag, and real-time reverse-transcriptase polymerase chain reaction analyses was employed to analyze differences between these two fungal stages in vitro. In all, 1,131 putative genes were hybridized with cDNA from different phases, resulting in 189 differentially expressed genes, and 4,595 reads were clusterized, producing 1,534 unigenes. The analysis of these genes, which represent approximately 21% of the total genes, indicates that the biotrophic-like phase undergoes carbon and nitrogen catabolite repression that correlates to the expression of phytopathogenicity genes. Moreover, downregulation of mitochondrial oxidative phosphorylation and the presence of a putative ngr1 of Saccharomyces cerevisiae could help explain its lower growth rate. In contrast, the saprotrophic mycelium expresses genes related to the metabolism of hexoses, ammonia, and oxidative phosphorylation, which could explain its faster growth. Antifungal toxins were upregulated and could prevent the colonization by competing fungi. This work significantly contributes to our understanding of the molecular mechanisms of WBD and, to our knowledge, is the first to analyze differential gene expression of the different phases of a hemibiotrophic fungus.
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Agaricales/genética , Agaricales/patogenicidade , Cacau/microbiologia , Agaricales/crescimento & desenvolvimento , Agaricales/fisiologia , Sequência de Bases , Carbono/metabolismo , Primers do DNA/genética , Elementos de DNA Transponíveis/genética , DNA Fúngico/genética , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/fisiologia , Mitocôndrias/metabolismo , Dados de Sequência Molecular , Nitrogênio/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Envenomation by Loxosceles spiders causes two main clinical manifestations: cutaneous and systemic loxoscelism. The factors contributing to the severity of loxoscelism are not fully understood. We have analysed biochemical and toxicity variations in venom of L. laeta and L. intermedia, with the aim to find a correlation with the seriousness of loxoscelism. Differences in expression of proteins, glycoproteins and sphingomyelinase activity were observed between venom from male and female spiders and between venom from the two species. These differences were reflected in the toxicity of the venoms including the capacity to induce complement-dependent haemolysis, dermonecrosis and lethality. Comparative analysis of gender and species, showed that these biological activities were more prominent in venom from female spiders, especially from L. laeta. Antiserum raised against venom from females L. laeta spiders had the highest efficacy in neutralizing venoms of males and females of both species. These results indicate that the severity of loxoscelism depends, at least partially, on the species and sex of the spider and suggest that for accidents involving L. laeta an specific serum therapy is necessary. Furthermore, it emphasizes the efficacy of the antiserum produced against L. laeta female venom in neutralizing Loxosceles venoms from different species and gender.
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Antivenenos/metabolismo , Pele/patologia , Picada de Aranha/metabolismo , Venenos de Aranha/química , Aranhas/química , Análise de Variância , Animais , Antivenenos/uso terapêutico , Western Blotting , Eletroforese em Gel de Poliacrilamida , Eritrócitos/efeitos dos fármacos , Feminino , Citometria de Fluxo , Hemólise/efeitos dos fármacos , Humanos , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Necrose/induzido quimicamente , Fatores Sexuais , Especificidade da Espécie , Esfingomielina Fosfodiesterase/metabolismo , Picada de Aranha/induzido quimicamente , Picada de Aranha/tratamento farmacológico , Venenos de Aranha/toxicidadeRESUMO
Loxosceles adelaida spiders (Araneae, Sicariidae) are found near and inside the caves in the Parque Estadual Turistico do Alto Ribeira (PETAR), Sao Paulo, Brazil, which are visited by thousands of tourists every year. Several Loxosceles species are a public health problem in many regions of the world, by causing severe dermonecrosis and/or complement dependent haemolysis upon envenomation. The aim of this study was to characterize the biochemical and biological properties of L. adelaida venom and evaluate the toxic potential of envenomation by this non-synanthropic Loxosceles species. The biological activities of the L. adelaida venom was compared to that of Loxosceles gaucho, a synanthropic species of medical importance in Brazil. L. adelaida venom showed a similar potential to induce haemolysis, dermonecrosis and lethality as L. gaucho venom. L. adelaida crude venom was purified, yielding a 31 kDa component endowed with haemolytic and dermonecrotic activities. In conclusion, we show here that the troglophile Loxosceles species, L. adelaida, commonly found in the complex of caves from PETAR, is potentially able to cause envenomation with the same gravity of those produced by synanthropic species.
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Hemólise/efeitos dos fármacos , Pele/patologia , Esfingomielina Fosfodiesterase/toxicidade , Venenos de Aranha/química , Aranhas/química , Animais , Western Blotting , Brasil , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel Bidimensional , Ensaio de Imunoadsorção Enzimática , Eritrócitos/efeitos dos fármacos , Citometria de Fluxo , Dose Letal Mediana , Camundongos , Necrose/induzido quimicamente , Coelhos , Especificidade da Espécie , Esfingomielina Fosfodiesterase/isolamento & purificação , Venenos de Aranha/enzimologia , Aranhas/enzimologiaRESUMO
PURPOSE: To determine whether experimentally measured upper and lower eyelid saccades can be fitted to a mathematical function. METHODS: A charge-coupled device video camera connected to a personal computer was used to record upper and lower eyelid saccades accompanying 20 degrees and 40 degrees of vertical eye rotation in 19 normal adult subjects. Movement analysis was performed with software that calculated the center of a blue spot in each frame. The damped harmonic oscillator model was used to fit all saccadic functions obtained. RESULTS: All downward and upward saccades of both upper and lower eyelids were fitted with the underdamped solution of the model with correlation coefficients ranging from 0.980 to 0.999 (mean = 0.995). It was possible to measure maximum velocity at any time, amplitude, and duration of the saccade movements. For the upper eyelid, downward saccades were faster than upward saccades, a difference that was not observed for the lower eyelid. For both the upper and lower eyelids, the velocity of upward and downward movements reached a peak at approximately 0.05/0.06 second and then decreased. For both the upper and lower eyelid saccades, there was good linear correlation between amplitude and velocity. Overshoots were detected in the downward saccades of both lids. CONCLUSIONS: Normal upper and lower saccades are described by functions that are extremely well fitted by the underdamped solution of the harmonic oscillator model. Overshooting is a typical feature of normal downward saccades and can be explained by the elastic properties of the tissues.
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Pálpebras/fisiologia , Movimentos Sacádicos/fisiologia , Adulto , Feminino , Humanos , Masculino , Modelos Teóricos , Fenômenos Fisiológicos Oculares , Gravação em VídeoRESUMO
Loxosceles adelaida spiders (Araneae, Sicariidae) are found near and inside the caves in the Parque Estadual Turístico do Alto Ribeira (PETAR), São Paulo, Brazil, which are visited by thousands of tourists every year. Several Loxosceles species are a public health problem in many regions of the world, by causing severe dermonecrosis and/or complement dependent haemolysis upon envenomation. The aim of this study was to characterize the biochemical and biological properties of L. adelaida venom and evaluate the toxic potential of envenomation by this non-synanthropic Loxosceles species. The biological activities of the L. adelaida venom was compared to that of Loxosceles gaucho, a synanthropic species of medical importance in Brazil. L. adelaida venom showed a similar potential to induce haemolysis, dermonecrosis and lethality as L. gaucho venom. L. adelaida crude venom was purified, yielding a 31 kDa component endowed with haemolytic and dermonecrotic activities. In conclusion, we show here that the troglophile Loxosceles species, L. adelaida, commonly found in the complex of caves from PETAR, is potentially able to cause envenomation with the same gravity of those produced by synanthropic species.
Assuntos
Animais , Aranhas/classificação , IntoxicaçãoRESUMO
The authors present the results of a study conducted using time series data from the 1993--2001 period in order to characterise the clinical behaviour of bovine paratuberculosis. The case data, confirmed by macroscopic examination, enzyme-linked immunosorbent assay (ELISA) and comparative tuberculin test, came from the herd health register, located in Tandil in the province of Buenos Aires, Argentina. The upper limit of customary variation was observed in April, with an incidence of 2.5%. In 1997, 1999, 2000 and 2001 the disease was epidemic and a peak of 5.6% occurred in March 1999. Over the long term a rise in the total annual incidence was observed, from 0.7% in 1993 to 10.2% in 2001. Knowledge about the epidemiology of paratuberculosis will help to control the disease and minimise its impact on the national economy, and will also provide new information for use in public health.
Assuntos
Doenças dos Bovinos/epidemiologia , Paratuberculose/epidemiologia , Saúde Pública , Animais , Argentina/epidemiologia , Bovinos , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/transmissão , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Incidência , Paratuberculose/prevenção & controle , Paratuberculose/transmissão , Teste Tuberculínico/veterináriaRESUMO
The control of cell death occurring in high density cultures performed in bioreactors is an important factor in production processes. In this work, medium nutrient removal or feeding was used to determine at which extension apoptosis could be, respectively, involved or prevented in VERO cell cultures on microcarriers. Glutamine and galactose present in the VERO cell culture medium was consumed after, respectively, 6 and 12 days of culture. Kinetics studies showed that fresh medium replacement and, to some extent, galactose or glutamine depleted-fresh medium replacement provided a nutritional environment, allowing the VERO cell cultures to attain high densities. Galactose was shown to be a more critical nutrient when cultures reached a high density. In agreement with that, VERO cell cultures supplemented with galactose and/or glutamine were shown to confirm previous findings and, again at high densities, galactose was shown to be a critical nutrient for VERO cell growth. These observations also indicated that in VERO cell cultures, for feeding purposes, the glutamine could be replaced by galactose. The inverse was not true and led, at high densities, to a decrease of cell viability. In the absence of glutamine and galactose, apoptosis was observed in VERO cell cultures by cytofluorometry, Acridine orange staining or light and electron microscopy, reaching high levels when compared to cultures performed with complete medium. VERO cells apoptosis process could be prevented by the galactose and/or glutamine feeding and, at high densities, galactose was more efficient in protecting the cultures. These cultures, prevented from apoptosis, were shown to synthesize high levels of measles virus following infection. Our data show that apoptosis prevention by glutamine/galactose feeding, led to high productive and metabolic active VERO cell cultures, as indicated by the high cell density obtained and the virus multiplication leading to higher virus titers.