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O objetivo deste artigo é mostrar que é possível gerir uma marca (branding) com recursos escassos, usando práticas simples mas teoricamente fundamentadas. Os autores – uma gestora de comunicação, um professor arquiteto e um professor de marketing – viram-se envolvidos na escolha de uma identidade – nome e logo – para uma reserva ecológica. Os recursos de dinheiro, tempo e meios técnicos eram escassos. Com base numa rápida abordagem semiótica, envolveram os públicos da marca na cocriação da sua identidade e conseguiram assim evitar uma escolha meramente estética que poderia ser difícil de implementar.

The OX513A strain ofLa souche OX513A d'La cepa OX513A deتمثل سلالة OX513A منOX513A 类Вид комаров Aedes aegypti под названием OX513A, разработанный британской компанией Oxitec, экспрессирует ограничивающий популяцию своего носителя трансген, который препятствует развитию личинки во взрослую особь. В апреле 2014 года Бразильская национальная техническая комиссия по биобезопасности завершила оценку рисков OX513A и пришла к выводу, что этот вид не представляет новых биологических угроз для человека или окружающей среды и может быть выпущен в Бразилии. Тогда Бразилия стала первой страной, в которой был разрешен неограниченный выпуск генетически измененных комаров. В ходе оценки комиссия опубликовала исчерпывающий перечень предполагаемых рисков и провела их систематический анализ. Такие риски включали потенциальную способность комаров неполовозрелой стадии, несущих трансген, дожить до репродуктивного возраста в случае неудавшейся экспрессии трансгена или его подавления, вызванного воздействием достаточного количества тетрациклина на комаров во внешней среде. Среди других предполагаемых рисков — потенциальная аллергенность или токсичность белков, образующихся в результате экспрессии гена, возможность дрейфа генов или повышенного распространения болезнетворных организмов для человека и заселение свободных мест размножения другими видами переносчиков. На фоне эпидемии вируса Зика лица, ответственные за разработку стратегических решений, регулирующие органы, а также общественность увеличили внимание к роли Ae. Aegypti в качестве переносчиков и выразили большую обеспокоенность по поводу выпуска мужских особей вида OX513A. По этой причине авторы данной статьи провели повторную оценку потенциальных рисков. Была подтверждена безопасность и высокое потенциальное значение выпуска генетически измененных комаров для борьбы с распространяемыми Ae. aegypti заболеваниями, такими как чикунгунья, денге и болезнь, вызываемая вирусом Зика.

The emergence of new technologies for genetic modification has broadened the range of possible new products. The regulations of many countries that could benefit from these new products may not be prepared to assess risks and enable science-based decision-making. This is especially acute in the case of genetically modified insects with potential use in public health and agriculture. Modifications of the regulatory framework, sometimes necessary to allow a proper risk assessment of products from new technologies, are strongly influenced by political decisions derived from the balance of power and interest among stakeholders. This article discusses the genesis of the Brazilian regulatory framework, its applicability for the risk assessment of genetically modified insects and the scenarios that have shaped the two biosafety laws that established the basis for the use of modern biotechnology in the country. It is concluded that, for the adoption of the new technologies, it is important to carefully navigate the political tensions by seeking the engagement and empowerment of stakeholders supporting science-based decision-making in order to gather the necessary support for adoption of risk assessment as the basis for final decisions, allowing the use of new technologies.

INTRODUCTION: The aim of this study was to determine the seroprevalence and risk factors associated with canine visceral leishmaniasis in Paraíba State. METHODS: Blood samples were collected from 411 dogs in four municipalities of Paraíba State. The seroprevalence was assessed by using ELISA. RESULTS: The seroprevalence ranged from 7.2% to 20%. The risk factors that were associated with the disease were the presence of ticks and contact with other animals. CONCLUSIONS: The seroprevalence of canine visceral leishmaniasis is high in Paraíba, indicating the need for health authorities to resume visceral leishmaniasis control activities. The ruralization of suburban areas in the region tends to homogenize the risk factors between suburban and rural areas.

We compared the performance of a locally produced β-mercaptoethanol-modified promastigote antigen (β-ME-Ag) of an indigenous Leishmania infantum strain against that of a trypsinized Leishmania donovani reference (REF-Ag) in the direct agglutination test (DAT) for detection of canine visceral leishmaniasis (CVL). One hundred and fifty-one serum samples collected from dogs belonging to four groups with different conditions were included. At a DAT titre of 1 : 320, statistically determined as optimal cut-off value for β-ME-Ag, and 1 : 160 for REF-Ag, a sensitivity and a specificity of 100 % were estimated for β-ME-Ag in comparison with 96.6 % and 100 %, respectively, for REF-Ag. Overall, levels of agglutination titres recorded for the two antigens were highly concordant (Cohen’s κ = 0.879) in both the CVL and non-CVL groups. Based on current results, and ease experienced in processing the antigen and reading the test outcome, we recommend incorporation of β-ME-Ag in DAT for confirmation or exclusion of suspected CVL in dogs.

Reducing the incidence of malaria has been a public health priority for nearly a century. New technologies and associated vector control strategies play an important role in the prospect of sustained reductions. The development of the CRISPR/Cas9 gene editing system has generated new possibilities for the use of gene-drive constructs to reduce or alter vector populations to reduce malaria incidence. However, before these technologies can be developed and exploited, it will be necessary to understand and assess the likelihood of any potential harms to humans or the environment. To begin this process, the Foundation for the National Institutes of Health and the International Life Sciences Institute Research Foundation organized an expert workshop to consider the potential risks related to the use of gene drives in Anopheles gambiae for malaria control in Africa. The resulting discussion yielded a series of consensus points that are reported here.

Resumo: No Brasil, a leishmaniose visceral é causada pela Leishmania infantum. É uma zoonose crônica e, frequentemente, fatal, sendo considerada um grave problema de saúde pública no mundo e reconhecida pela Organização Mundial de Saúde como uma das dezessete "Doenças Tropicais Negligenciadas". O presente estudo foi realizado em 2012, na zona rural do município de Patos, semiárido paraibano, com o objetivo de estimar a prevalência, os fatores de risco da leishmaniose visceral canina (LVC) na região e avaliar os testes de diagnóstico sorológico. Foram coletadas 362 amostras de sangue e a prevalência da infecção foi determinada através de três técnicas sorológicas (ELISA, RIFI e Teste Imunocromatográfico DPP - Dual Path Plataform), sendo consideradas positivas as amostras que apresentaram pelo menos dois testes reagentes. As amostras positivas na sorologia foram testadas na PCR e qPCR. Aplicou-se um questionário epidemiológico aos proprietários para identificação dos possíveis fatores de risco. A taxa de prevalência foi de 11,33% (41/362). Considerou-se o ELISA como padrão ouro, já que é o teste confirmatório para a LVC pelo Ministério da Saúde. O DPP (Dual Path Plataform) apresentou sensibilidade de 58% (95% CI: 0,43-0,72) e especificidade de 96% (95% CI: 0,93-0,98), com índice Kappa de 0,57. A RIFI apresentou sensibilidade de 85% (95% CI: 0,72-0,94), especificidade de 99% (95% CI: 0,98-1) e valor Kappa de 0,88. O fator de risco identificado na análise multivariada por regressão logística múltipla foi o sexo (OR=2,15 [1,09-4,21]) e os cães machos apresentaram 2,15 vezes mais chances de serem infectados, que pode ser justificado por serem mais utilizados para a caça e como cão de guarda, dois fatores que aumentam a exposição do animal ao flebótomo. Em função da taxa de prevalência encontrada, indica-se a aplicação de medidas de controle no município. Os resultados da comparação dos ensaios sorológicos demonstraram que o DPP (Dual Path Plataform) não é a melhor técnica para triagem dos animais positivos em função da baixa sensibilidade do método, sugerindo que o mesmo seja substituído pelo ELISA. Abstract: Visceral leishmaniasis is caused by Leishmania infantum in Brazil. It is a chronic disease and often a fatal zoonosis and considered as a serious worldwide public health problem and recognized by the World Health Organization as one of seventeen "Neglected Tropical Diseases". This study was conducted in 2012 in the county of Patos, in Paraíba State semiarid region. The main purposes were to estimate the prevalence and the risk factors of canine visceral leishmaniasis (CVL), and to evaluate the performance of serological tests. Serological prevalence was determined using three techniques (ELISA, IFA and DPP chromatographic immunoassay - Dual Path Platform). ELISA was the golden standard, since it is the confirmatory test for CVL as established by the Brazilian Ministry of Health. In total, 362 blood samples were collected and were considered positive if positive by two serological assays. Positive samples were tested by PCR and qPCR. An epidemiological questionnaire was applied to the dog owner to identify risk factors associated with CVL. The seroprevalence was 11.33% (41/362). Chromatographic immunoassay - DPP showed a sensitivity of 58% (95%, CI: 0.43 to 0.72) and specificity of 96% (95%, CI: 0.93-0.98) , with a Kappa index of 0.5. The IFA had a sensitivity of 85% (95%, CI: 0.72 to 0.94), specificity of 99% (95%, CI: 0.98 to 1) and Kappa value of 0.8. The risk factor identified in the multivariate analysis was gender (OR=2.15 [1.09 to 4.21]), male dogs having 2.15 times more chance of being infected. The increased likelihood can possibly be explained by the use of male dogs for hunting and as guard dogs, two factors that increase dog contact to infected sandflies. Due to the prevalence rates, it should be recommended control measures against canine visceral leishmaniasis. The results demonstrated that the Chromatographic immunoassay (DPP-Dual Path Platform) is not the best technique for screening positive animals due to its low sensitivity, suggesting its replacement by ELISA.

The aim of this work was to isolate and identify bacteria able to degrade sodium fluoroacetate from soil and plant samples collected in areas where the fluoroacetate-containing plantsMascagnia rigidaandPalicourea aenofuscaare found. The samples were cultivated in mineral medium added with 20 mmol L−1sodium fluoroacetate. Seven isolates were identified by 16S rRNA gene sequencing asPaenibacillussp. (ECPB01),Burkholderiasp. (ECPB02),Cupriavidussp. (ECPB03),Staphylococcussp. (ECPB04),Ancylobactersp. (ECPB05),Ralstoniasp. (ECPB06), andStenotrophomonassp. (ECPB07). All seven isolates degraded sodium-fluoroacetate-containing in the medium, reaching defluorination rate of fluoride ion of 20 mmol L−1. Six of them are reported for the first time as able to degrade sodium fluoroacetate (SF). In the future, some of these microorganisms can be used to establish in the rumen an engineered bacterial population able to degrade sodium fluoroacetate and protect ruminants from the poisoning by this compound.

Leishmania (L.) chagasiis the etiological agent of visceral leishmaniasis, an important endemic zoonosis in the American continent, as well as in many other countries in Asia, Africa, and Mediterranean Europe. The treatment is difficult due to the high toxicity of the available drugs, high costs, and emergence of resistance in the parasites. Therefore, there is an urgent need for new leishmanicidal agents. The bisbenzylisoquinoline alkaloids have been related to antibacterial, antiprotozoal, and antifungal activities. The aim of this study was to evaluate the growth inhibitory activity of warifteine (bisbenzylisoquinoline alkaloid) againstL. chagasipromastigotes in axenic cultures and the occurrence of drug-induced ultrastructural changes in the parasite. This bisbenzylisoquinoline alkaloid was isolated from the leaves and roots ofCissampelos sympodialisEichl. (Menispermaceae), a plant commonly used for the treatment of various diseases in Brazilian folk medicine. Using the purified warifteine, the 50% inhibitory concentration (IC50) was determined at 0.08 mg/mL after 72 h in culture, inducing significant changes in the parasite morphology, like aberrant multisepted forms and blebs in the plasma membrane. In conclusion, warifteine represents an attractive candidate for future pharmacological studies aiming new leishmanicidal drugs.

Este trabalho objetivou o estabelecimento de condições favoráveis ao crescimento micelial de M. musicola in vitro, pela avaliação em quatro experimentos, da influência de diferentes meios de cultura (BDA, BDA/IFB, V8, V8/IFB, V8/CaCO3 e V8/CaCO3/IFB); combinações de fontes de carbono (dextrose, maltose, sacarose e xilose) e nitrogênio (peptona, glicina, nitrato de potássio e de sódio); valores de pH (6,8; 6,4; 5,7 e 4,9) e regimes luminosos (escuro contínuo, alternância luminosa e claro contínuo). Observou-se um maior crescimento de M. musicola quando cultivado nos meios de cultura BDA/IFB, V8/IFB e BDA. As fontes de carbono sacarose, maltose e dextrose quando combinadas com a peptona como fonte de nitrogênio, promoveram um maior crescimento micelial de M. musicola. O meio de cultura BDA/IFB, com o valor final de pH ajustado para 5,7, em regime de escuro contínuo, apresentou-se como o melhor para o crescimento de M. musicola.This work aimed the establishment of the best growth conditions of M. musicola mycelia in vitro through the analysis of the influence of different culture media (BDA, BDA/IFB, V8, V8/IFB, V8/CaCO3 and V8/CaCO3/IFB), combinations of carbon (dextrose, maltose, sucrose and xylose) and nitrogen (peptone, glycine, potassium nitrate and sodium nitrate) sources, medium pH values (6.8, 6.4, 5.7 and 4.9) and photoperiods (continuous darkness, alternating darkness/lightness and continuous lightness). At the end of the evaluation period, cultural parameters and the dry weights of colonies were annotated. BDA/IFB, V8/IFB and BDA culture media promoted the best mycelial growth. The experiments also demonstrated that dextrose and sucrose when combined with peptose as a nitrogen source, are the best carbon sources as they promoted the most vigorous mycelial growth. The use of BDA/IFB culture medium, with its final pH adjusted to 5.7, and a photoperiod of continuous darkness was the best condition for the growth of M. musicola.

OBJECTIVES: the aim of this study was to verify certain processes that are related to the occupation of urban areas and which contribute to the occurrence and expansion of kala-azar in a medium-sized town undergoing economic growth with a high influx of migrants. METHODS: the study is an epidemiological cross-section, in which house-to-house investigation was conducted concerning cases registered in 8 districts and their respective census areas, all in the municipality of Petrolina, Pernambuco state, Brazil, from 1992 to 1997. The study was backed up by laboratory research, taking into consideration both the transmitter and animal reservoir. An explanatory social determination model for the health-illness process of this endemic-epidemic situation was used. RESULTS: a concentration of kala-azar cases was observed in the urban periphery of the town of Petrolina, in areas of squatter settlement and growth, where basic sanitation was precarious, in which animals and the vector were present around the household and the population had a low level of schooling. Males and the 0-4 age group were the most affected. CONCLUSIONS: the findings suggest the establishment of a new epidemiological pattern for kala-azar in Petrolina, where this endemic occurs in areas that have been highly modified by the population. Such a situation characterises the ruralisation process of the urban peripheries endemic in large cities.

Summary Serodiagnosis of visceral leishmaniasis is often hindered by cross-reactions to other parasitic diseases. Identifying specific B-cell epitopes in proteins is therefore important for immunodiagnostics, as well as for disease control by vaccines. This study aimed to identify linear and conformational B-cell epitopes and to evaluate the secondary structure of antigen proteins in Leishmania infantum using in silico analysis. Linear epitopes were predicted using the Immune Epitope Database and Analysis Resource (IEDB), BepiPred and BcePred programs. The conformational B-cell epitopes were identified using the CBTOPE server. The combination of the predictions using IEDB, BepiPred and BcePred generated 148 linear epitopes from the calpain-like cysteine peptidase (CP), thiol-dependent reductase 1 (TDR1) and HSP70 proteins. In total, 164 conformational epitopes were predicted, mostly located in the linear epitope region. The predicted epitopes are located in α helix and random coil regions in the thiol-dependent reductase 1 and HSP70 proteins. New linear and conformational B-cell epitopes of L. infantum proteins were identified in silico, and the prediction using various programs ensures greater accuracy of the results, as suggested by confirmation of previously identified HSP70 epitopes.

Two immunoglobulin G enzyme-linked immunosorbent assay (ELISA) versions using whole promastigotes of Leishmania infantum (syn. Leishmania chagasi) treated either with β-mercaptoethanol (β-ME-ELISA) or trypsin (TRYP-ELISA) as antigens were developed for the diagnosis of canine visceral leishmaniasis (CVL). By comparison with the direct agglutination test (DAT; 100%, 31/31; 95% confidence interval [CI]: 86.3–100%), slightly lower sensitivity was demonstrated for the newly developed β-ME-ELISA (93.5%, 29/31; 95% CI: 77.2–98.9%). Sensitivity was higher for β-ME-ELISA compared with TRYP-ELISA (87.1%, 27/31; 95% CI: 69.2–95.8%) in serum samples from dogs with CVL. When tested with sera from 37 healthy dogs and from 45 dogs with clinical conditions other than CVL, a specificity of 97.6% (80/82; 95% CI: 90.1–99.6%) was estimated for β-ME-ELISA as compared to 100% (82/82; 95% CI: 94.4–100%) and 95.1% (78/82; 95% CI: 87.3–98.4%) for DAT and TRYP-ELISA, respectively. Observed agreement was 94.0% (95% CI: 88.7–97.1%) between DAT and β-ME-ELISA (κ = 0.879; 95% CI: 0.803–0.956) and 87.4% (95% CI: 80.8–92.1%) between DAT and TRYP-ELISA (κ = 0.743; 95% CI: 0.636–0.851). Current results advocate application of the new β-ME-ELISA for diagnosis of CVL at the laboratory level and confirmation of results obtained with the DAT in field studies.

Ehrlichiosis and anaplasmosis are tick-borne diseases.Ehrlichia canisandAnaplasma platysinfect mainly white cells and platelets, respectively. The main DNA source for PCR is peripheral blood, but the potential of blood cell fractions has not been extensively investigated. This study aims at assessment of whole blood (WB) and blood fractions potential in nested PCR (nPCR) to diagnose canine ehrlichiosis and anaplasmosis. The 16S rRNA gene was amplified in 71.4, 17.8, 31.57, and 30% of the WB, granulocyte (G), mononuclear cells (M), and buffy coat (BC) samples. Compared to the WB, the sensitivity of the PCR was 42.86% for the M, and BC fractions, 21.43% for the G, and 33.33% for the blood clot (C). There was fair agreement between the WB and M, BC and C, and slight with the G. Fair agreement occurred between the nPCR and morulae in the blood smear. One animal was coinfected withA. platysandE. canis. This study provided the first evidence ofA. platysinfection in dogs in Paraíba, Brazil, and demonstrated that WB is a better DNA source than blood fractions to detectEhrlichiaandAnaplasmaby nPCR, probably because of the plasma bacterial concentration following host cell lysis.

The objective of this paper was to report the isolation of two fluoroacetate degrading bacteria from the rumen of goats. The animals were adult goats, males, crossbred, with rumen fistula, fed with hay, and native pasture. The rumen fluid was obtained through the rumen fistula and immediately was inoculated 100 μL in mineral medium added with 20 mmol L−1sodium fluoroacetate (SF), incubated at 39°C in an orbital shaker.Pseudomonas fluorescens(strain DSM 8341) was used as positive control for fluoroacetate dehalogenase activity. Two isolates were identified by 16S rRNA gene sequencing asPigmentiphaga kullae(ECPB08) andAncylobacter dichloromethanicus(ECPB09). These bacteria degraded sodium fluoroacetate, releasing 20 mmol L−1of fluoride ion after 32 hours of incubation in Brunner medium containing 20 mmol L−1of SF. There are no previous reports of fluoroacetate dehalogenase activity forP. kullaeandA. dichloromethanicus. Control measures to prevent plant intoxication, including use of fences, herbicides, or other methods of eliminating poisonous plants, have been unsuccessful to avoid poisoning by fluoroacetate containing plants in Brazil. In this way,P. kullaeandA. dichloromethanicusmay be used to colonize the rumen of susceptible animals to avoid intoxication by fluoroacetate containing plants.

Lutzomyia umbratilis, a known vector of Leishmania guyanensis in the north of Amazon basin, has been exclusively found in the Amazonian region. Here we report for the first time the occurrence of this species in northeastern Brazil. The epidemiological importance of the occurrence of this species in the Atlantic Forest is commented.

Brazil is presently (2010) the second largest producer of Genetically Modified (GM) crops. The legal framework to support both research activities and the commercial release of Genetically Modified Organisms (GMOs) is, however, very recent, as the Biosafety Law dates back from 2005. After the indispensable risk analysis, done by National Technical Committee for Biosafety (CTNBio), a GM plant can be approved for commercial release. Nevertheless, as stated in the Normative Resolution nr. 5 (NR-5), 2008, the post-market monitoring is mandatory. However, the first GM crop in Brazil, the herbicide tolerant soybean, was harvested in 2005. The CTNBio asked, then, for a monitoring plan and the applicant designed a complex study focused on case-specific monitoring. After four years the detailed field studies proved that no harm derived from this crop. The costs, nevertheless, were enormous. In May 2010, 21 GM plants were already approved for commercial release in Brazil, corresponding to different events in soybean (6), cotton (8) and maize (9). Single and stacked events tolerant to herbicides or insect-resistant are presently been planted for all three crops. If, for each single event and for the stacks, a laborious post market monitoring plan were to be executed, the total costs would be unbearably high. The applicant, i.e. the seed company in the case of the three common crops, is legally responsible for the monitoring in Brazil. It is also responsible to produce an adequate monitoring plan. Since the rules in the Normative Resolution nr. 5 are far from being clear, the applicants either propose an elaborated plan for case-specific monitoring or, conversely, submit a very simple plan, targeting some potential adverse effect that can be more easily evaluated in commercial fields. All data generated must be reported to federal agencies belonging to at least three different ministries. Monitoring is also a responsibility of some federal agencies, as stated in the Biosafety Law, like registration and inspection agencies and other entities, which are responsible for, among other duties, keep updated information in the Biosafety Information Systems (SIB) of institutions and technical responsible individuals that carry out activities and projects related to GMOs and their by products. It is not clearly stated either in the Biosafety Law or in the NR-5 that monitoring should be split in case-specific monitoring and general surveillance, as adopted in Europe. If case-specific monitoring plans are difficult to design, a sensible suggestion for the general surveillance was not yet achieved. Nevertheless, the info-concentrating SIB may be a valuable source for the general surveillance, once it starts to operate. In conclusion, due to the lack of clear information about how to produce an adequate monitoring plan, stakeholders either tend to unnecessarily enlarge the monitoring scope or shorten it to a few objectives. The general surveillance is either not contemplated in the monitoring plans or minimally treated. It is important to keep in mind that the applicants are responsible to produce most of the data, even for the general surveillance, and this can be extremely difficult in a scenario where 20 or more different events are cultivated, frequently in neighboring fields. The EuropaBio approach to general surveillance for cultivation of GM crops (available from Nature Precedings "doi:10.1038/npre.2010.4451.1":http://dx.doi.org/10.1038/npre.2010.4451.1) is difficult to be largely adopted: farmers may be unable to meaningfully answer the questionnaire and the network has a very restricted number of potential participants. CTNBio is aware of these challenges and has already started to adjust the NR-5 to better guide the applicants in their writing of monitoring plans.

In this work we focused on a recombinant protein, containing approximately 230 aminoacids from the carboxy-terminal extremity of the Leishmania chagasi heat shock protein 70. The heat shock proteins are among the most abundant parasite antigens and conserved proteins in nature, and this family is one of the most immunogenic proteins present within pathogenic organisms. The recombinant protein has been partially purified by electroelution and further precipitation in acetone. The electroelution process did not modify its immunological and antigenic properties, as it continued to be recognized by visceral leishmaniasis positive sera and by the immunological system of rabbits during the immunization, both in ELISA and Western blots. The production of polyclonal sera with an antigen concentration that is far from the maximum dose, strengthens the idea that the proteins of this family are highly antigenic and immunogenic. Our results with these polyclonal sera in the Direct Agglutination Assay allow the conclusion that the Leishmania chagasi native heat shock protein 70 is distributed on the surface of the parasite. Neste trabalho estudamos urna proteína recombinante (S7) contendo aproximadamente 230 aminoácidos da extremidade carboxi-terminal da proteína de choque térmico de 70 kDa (HSP70) de Leishmania chagasi. As proteínas de choque térmico estâo entre os antígenos parasitarios mais abundantes e mais conservados na natureza. Esta familia pertence a urna das classes de proteínas mais imunogênicas, presentes em organismos patogênicos. Aproteína S7 foi parcialmente purificada por eletroeluição, e em seguida precipitada em acetona. A eletroeluição não modificou suas propriedades imunológicas e antigênicas, pois a proteína continuou a ser reconhecida (tanto no ELISA como no Western blot) por soros positivos para leishmaniose visceral e pelo sistema imunológico de coelhos durante a imunização. Aproducção de soros policlonais com urna concentração antigênica muito inferior a dose máxima, reforca a idéia de que as proteínas desta familia sâo altamente antigênicas e imunogénicas. Nossos resultados com os soros policlonais no ensaio de aglutinação direta (DAT) permitem concluir que a HSP70 nativa de L. chagasi está presente na superficie do parásita.

The current therapy for leishmaniasis, which affects annually about 2 million people, is far from satisfactory. All available drugs require parenteral administration and are potentially toxic. Plant essential oils have been traditionally used in folk medicine and appear as valuable alternative source for chemotherapeutic compounds. In this study, we demonstrated the effect of essential oils from Cymbopogon citratus, Lippia sidoides, and Ocimum gratissimum on growth and ultrastructure of Leishmania chagasi promastigote forms. Steam distillation was used to isolate the essential oils, and their constituents were characterized by gas chromatography coupled to mass spectrometry and nuclear magnetic resonance. All essential oils showed in vitro inhibitory action on L. chagasi promastigotes growth in a dose-dependent way, with IC(50)/72 h of 45, 89, and 75 microg/mL for C. citratus, L. sidoides, and O. gratissimum, respectively. Drastic morphological alterations were observed in all essential oil-treated parasites, including cell swelling, accumulation of lipid droplets in the cytoplasm, and increase of acidocalcisome volume. Furthermore, aberrant-shaped cells with multi-septate body were observed by scanning electron microscopy, suggesting an additional effect on cytokinesis. Taken together, our data show that these essential oils affect the parasite viability being the C. citratus essential oil the most effective against L. chagasi.

Este trabalho objetivou o estabelecimento de condições favoráveis ao crescimento micelial de M. musicola in vitro, pela avaliação em quatro experimentos, da influência de diferentes meios de cultura (BDA, BDA/IFB, V8, V8/IFB, V8/CaCO3 e V8/CaCO3/IFB); combinações de fontes de carbono (dextrose, maltose, sacarose e xilose) e nitrogênio (peptona, glicina, nitrato de potássio e de sódio); valores de pH (6,8; 6,4; 5,7 e 4,9) e regimes luminosos (escuro contínuo, alternância luminosa e claro contínuo). Observou-se um maior crescimento de M. musicola quando cultivado nos meios de cultura BDA/IFB, V8/IFB e BDA. As fontes de carbono sacarose, maltose e dextrose quando combinadas com a peptona como fonte de nitrogênio, promoveram um maior crescimento micelial de M. musicola. O meio de cultura BDA/IFB, com o valor final de pH ajustado para 5,7, em regime de escuro contínuo, apresentou-se como o melhor para o crescimento de M. musicola. This work aimed the establishment of the best growth conditions of M. musicola mycelia in vitro through the analysis of the influence of different culture media (BDA, BDA/IFB, V8, V8/IFB, V8/CaCO3 and V8/CaCO3/IFB), combinations of carbon (dextrose, maltose, sucrose and xylose) and nitrogen (peptone, glycine, potassium nitrate and sodium nitrate) sources, medium pH values (6.8, 6.4, 5.7 and 4.9) and photoperiods (continuous darkness, alternating darkness/lightness and continuous lightness). At the end of the evaluation period, cultural parameters and the dry weights of colonies were annotated. BDA/IFB, V8/IFB and BDA culture media promoted the best mycelial growth. The experiments also demonstrated that dextrose and sucrose when combined with peptose as a nitrogen source, are the best carbon sources as they promoted the most vigorous mycelial growth. The use of BDA/IFB culture medium, with its final pH adjusted to 5.7, and a photoperiod of continuous darkness was the best condition for the growth of M. musicola.

In Latin America, Lutzomyia longipalpis is the principal vector of Leishmania chagasi, and is associated with the majority of active foci of visceral leishmaniasis. In spite of the fact that this sand fly is spread practically throughout the entire Neotropical Region, its distribution is not uniform due to geographic and environmental barriers. Geographic isolation coupled with reduced flight abilities may contribute to the appearance of cryptic species of Lutzomyia longipalpis, which may differ in their capacity to transmit L. chagasi. In this work, we describe the genetic structuring patterns based on polymorphism analysis of 24 RAPD-PCR loci of 7 natural populations of Lutzomyia longipalpis obtained from Brazil's northeastern region. The estimated degree of genetic differentiation between populations, based on the population subdivision index θST (0.136), suggests a moderate degree of genetic structuring as a result of geographical isolation and restricted gene flow. Genetic distances were found to be compatible with those found between members of a single species, suggesting a taxonomic uniformity of Lutzomyia longipalpis in the region studied.

Chemotherapy for Chagas' disease is still unsatisfactory due to toxicity and limited effectiveness of the available drugs. In this work we have investigated the effect of usnic acid, isolated from lichen Cladonia substellata , against Trypanosoma cruzi , in vitro. Incubation of culture epimastigotes with 5–30 μg/ml of this compound resulted in growth inhibition in a dosis-dependent manner. Ultrastructural analysis of treated epimastigotes showed damage to mitochondria, with a marked increase in kinetoplast volume and vacuolation of the mitochondrial matrix. Intense lysis of bloodstream trypomastigotes was observed with all drug concentrations tested. Besides mitochondrial and kinetoplast damage, trypomastigotes also presented enlargement of the flagellar pocket, as well as intense cytoplasm vacuolation. Treatment of infected macrophages with 40 or 80 μg/ml usnic acid induced marked cytoplasm vacuolation in intracellular amastigote forms, with disorganization of parasite kinetoplast and mitochondria, but with no significant ultrastructural damage to the host cells.

The Brazilian National Biosafety Committee approved in 2011 a new post release monitoring system for environmental releases of genetically modified organisms. It has a number of novel features in comparison with other established or proposed systems. The new system also allows the proponent to ask for monitoring exemption. General surveillance forms the basis of the monitoring system, similar to the European model, but differs markedly in the way it operates. While the European proposal is based on monitoring measurable variables extracted from environmental observations, from baselines previously established for multiple protection targets, the Brazilian system uses direct alerts of damage, without the aid of baseline values. The strength of the Brazilian form of monitoring is the possibility of generating an information network with the effective participation of many actors from the monitored area. A network constituted by highly qualified members, as proposed elsewhere, is too complex and unrealistic in Brazil and in many other countries. In conclusion, the Brazilian monitoring system is flexible and can be adjusted to the Brazilian reality over the next years, as a response to the ever growing experience in monitoring. It also meets the demands of the Brazilian society for transparency, rational use of resources, opportunity for national companies, and food and environmental biosafety.

Summary Two-hundred and sixty-five human sera from Brazil were tested in a direct agglutination assay using trypsinated Leishmania donovani donovani antigen. The assay proved to be of value for the diagnosis of American visceral leishmaniasis in that it was discriminative toward Chagas' disease.

O jogo de pressões seletivas que se estabelece na relação agente infeccioso/hospedeiro tende a uma condição em que a garantia de sobrevivência seja máxima para ambos. Considerando este aspecto, propomos um modelo no qual è possível avaliar o grau de adaptação do hospedeiro ao agente infeccioso, e vice-versa, partindo de relações epidemioiógicas bastante simples.Selective pressures playing, on the interaction between an infectious agent and its host lead to a condition of maximal survival for both. Based on simple epidemiological relationships, we propose a model which permits the evaluation of the degree of adaptation of a host to the infectios agent.