Correlation of extracellular enzymes activity of Candida glabrata clinical isolates with in vivo pathogenicity in Galleria mellonella larvae / 中华预防医学杂志

Objective: To explore the relationship between extracellular enzymes activity and virulence of Candida glabrata clinical isolates based on the infection model of Galleria mellonella larvae. Methods: Using experimental research methods, 71 strains of non-repetitive Candida glabrata were collected from Qinghai Provincial People's Hospital from June 2021 to January 2022. Bovine serum protein agar medium, egg yolk agar medium, sheep blood agar medium, Tween-80 agar medium and triglyceride agar medium were used to detect the aspartyl protease activity, phospholipase activity, hemolysis activity, esterase activity and lipase activity of Candida glabrata. Median lethal concentration (LC50) was calculated by using 1.25×108 CFU/ml,2.50×108 CFU/ml,3.75×108 CFU/ml,5.00×108 CFU/ml suspension of Candida glabrata ATCC2001 to infect Galleria mellonella larvae. Histopathological and etiological analysis was performed to determine whether the infection model was successfully established. The clinical isolates of Candida glabrata were configured to infect Galleria mellonella larvae with LC50 concentration to detect the pathogenicity of Galleria mellonella larvae.Spearman test or Pearson test were used to analyze the correlation between the extracellular enzyme activity of Candida glabrata clinical isolates and the pathogenicity of Galleria mellonella larvae. Results: 71 strains of Candida glabrata isolated clinically were detected to have low hemolytic activity after 2 days of culture. Aspartyl protease was detected after 4 days of culture, among which 7 strains (9.86%), 19 strains (26.76%) and 45 strains (63.38%) showed low, medium and high aspartyl protease activity. After 7 days of culture, 71 strains did not detect phospholipase, esterase and lipase activities. Candida glabrata on Galleria mellonella larvae of LC50=2.5×108 CFU/ml Fungal spore were found in the intestinal tissue pathological section of Galleria mellonella larvae in the experimental group, and Candida glabrata was identified by the microbial Mass Spectrometry after culture, while no fungi were found in the pathological section and culture of the control group. Spearman test shows that, there was a linear positive correlation between aspartyl protease activity and the survival rate of Galleria mellonella larvae (r = 0.73, P<0.01), the difference was statistically significant.Pearson test shows that, there was no significant linear relationship between hemolytic activity and survival rate of Galleria mellonella larvae (r = 0.16, P = 0.34), the difference was not statistically significant. Conclusion: The clinical isolates of Candida glabrata in this study had aspartyl protease activity and low hemolytic activity, but no phospholipase, esterase and lipase activity. The activity of aspartyl aspartyl protease of Candida glabrata was positively correlated with the pathogenicity of Galleria mellonella larvae.

Efecto de la temperatura y salinidad en la eclosión y supervivencia de Aedes aegypti (L) (Diptera: Culicidae) procedentes del occidente de México / Effect of temperature and salinity on the eclosion and survival of Aedes aegypti (L) (Diptera: Culicidae) from Western Mexico

Introducción: Aedes aegypti (L) (Diptera: Culicidae), es una especie cosmopolita y vector de arbovirosis. Las variaciones de la temperatura y salinidad del agua influyen en la eclosión y supervivencia de fases larvales. Objetivo: Evaluar el efecto de diferentes temperaturas y salinidades en la eclosión de huevos y la supervivencia de larvas, pupas y adultos bajo condiciones de laboratorio. Métodos: Se colectaron larvas de Ae. aegypti, de reservorios artificiales en la zona periurbana de Puerto Vallarta, Jalisco, México, y se mantuvieron hasta la fase adulta. Los huevos obtenidos se sometieron a ocho temperaturas (15, 17, 20, 25, 27, 30, 32 y 35 °C). Se colocaron 15 huevos por quintuplicado y se evaluó la eclosión durante 96 h. Se colocaron 100 huevos con agua ajustada a 0.3, 2, 5, 10, 15,18 y 22 ups y se evaluó la eclosión hasta las 96 h. Adicionalmente se utilizaron larvas del estadio IV, por quintuplicado, sometiéndose a las mismas salinidades y se evaluó la supervivencia hasta las 48 h. El efecto de la salinidad en la ovoposición de las hembras se llevó a cabo introduciendo recipientes con las mismas concentraciones salinas, dentro en las jaulas entomológicas. Resultados: Se registró el 100 por ciento de eclosión a las 24 y 48 h; la temperatura de 35° C no registró eclosión. Las salinidades de 22 y 18 ups, provocaron mortalidad del 100 por ciento a las 24 h. En la salinidad de 15 ups, sobrevivió el 50 por ciento. Las concentraciones de 2, 5 y 10 ups demostraron 100 por ciento de supervivencia hasta la fase de adulto. La supervivencia de larvas del estadio IV en los tratamientos 2, 5 y 10 fue del 100 por ciento y en 15,18 y 22 ups disminuyó a 50, 80 y 100 por ciento, respectivamente (p˂ 0,05). Las diferentes concentraciones salinas no afectaron significativamente la ovoposición. La eclosión solo se presentó en las concentraciones de 0,3; 2; 5 y 10 ups. Los huevos ovopositados en concentraciones de 15, 18 y 22 ups no eclosionaron hasta que fueron transferidos a agua dulce con porcentajes de eclosión de entre el 80 y 90 por ciento. Conclusiones: Los embriones de Ae. aegypti poseen una amplia plasticidad para soportar cambios drásticos de temperatura y salinidad. El control efectivo de sus poblaciones debe incluir la revisión de charcas o reservorios que contengan aguas salobres hasta 18 ups(AU)

Introduction: Aedes aegypti (L) (Diptera: Culicidae) is a cosmopolitan species and a vector of arboviruses. Variations in the temperature and salinity of the water affect eclosion and survival during the larval stages. Objective: Evaluate the effect of different temperatures and salinities on the eclosion of eggs and the survival of larvae, pupae and adults in laboratory conditions. Methods: Ae. aegypti larvae were collected from artificial reservoirs in a peri-urban area of Puerto Vallarta, Jalisco, Mexico, and maintained until the adult stage. The eggs obtained were subjected to eight temperatures (15, 17, 20, 25, 27, 30, 32 and 35 °C). Fifteen eggs were placed in quintuplicate and eclosion was evaluated for 96 h. One hundred eggs were placed with water adjusted to 0.3, 2, 5, 10, 15, 18 and 22 psu and eclosion was evaluated until 96 h. Additionally, stage IV larvae were used in quintuplicate, subjecting them to the same salinities and evaluating survival until 48 h. The effect of salinity on oviposition by females was determined by introducing containers with the same salinity into the entomological cages. Results: 100 percent eclosion was recorded at 24 and 48 h, whereas no eclosion occurred at a temperature of 35 °C. Salinities of 22 and 18 psu caused 100 percent mortality at 24 h, whereas 50 percent survived at a salinity of 15 psu. At concentrations of 2, 5 and 10 psu 100 percent of the larvae survived until the adult stage. Survival of stage IV larvae in treatments 2, 5 and 10 was 100%, whereas in 15, 18 and 22 psu it fell to 50, 80 and 100 percent, respectively (p˂ 0.05). The different salinities did not affect oviposition significantly. Eclosion only occurred at concentrations of 0.3, 2, 5 and 10 psu. Oviposited eggs at concentrations of 15, 18 and 22 psu did not eclose until they were transferred to fresh water, where eclosion percentages ranged between 80 percent and 90 percent. Conclusions: Ae. aegypti embryos have great plasticity to endure drastic changes in temperature and salinity. Effective control of their populations should include inspection of ponds and reservoirs containing brackish water of up to 18 psu(AU)

Potential of endophytic fungi as biocontrol agents of Duponchelia fovealis (Zeller) (Lepidoptera: Crambidae) / Fungos endofíticos para o biocontrole de Duponchelia fovealis (Zeller) (Lepidoptera: Crambidae)

Abstract This study reports the first assessment of endophytic fungi isolated from strawberry leaves and selection of isolates for the control of Duponchelia fovealis, a new pest of strawberries. A total of 400 strawberry leaves of the cultivar 'Albion' were collected in four commercial farms. Leaves were disinfected, cut in fragments, and placed on Petri dishes containing potato dextrose agar media with tetracycline and incubated for 30 days. Following this time, 517 fungal colonies were isolated, and thirteen genera were identified: Cladosporium, Aspergillus, Nigrospora, Fusarium, Trichoderma, Chaetomium, Alternaria, Paecilomyces, Penicillium, Ulocladium, Bipolaris, Diaporthe, and Phoma. Eight isolates belonging to the genera Aspergillus, Diaporthe, Paecilomyces, and Cladosporium were selected for pathogenicity bioassays against third instar larvae of D. fovealis. Isolates of Paecilomyces induced the highest mortality rates.

Resumo Este trabalho apresenta a primeira contribuição no isolamento de fungos endofíticos de folhas de morangueiro e na seleção de isolados para controle de Duponchelia fovealis, uma nova praga do morangueiro. Foram coletadas 400 folhas da cultivar 'Albion' em quatro lavouras comerciais de morangueiro. As folhas foram desinfetadas, cortadas em fragmentos e depositadas em placas de Petri contendo Ágar Batata Dextrose como meio, em conjunto com tetraciclina e incubados durante 30 dias. Um total de 517 colônias fúngicas e treze gêneros foram isolados: Cladosporium, Aspergillus, Nigrospora, Fusarium, Trichoderma, Chaetomium, Alternaria, Paecilomyces, Penicillium, Ulocladium, Bipolaris, Diaporthe e Phoma. Oito isolados pertencentes aos gêneros Aspergillus, Diaporthe, Paecilomyces e Cladosporium foram selecionados para os bioensaios de virulência contra larvas de 3º instar de D. fovealis. Isolados de Paecilomyces causaram as maiores taxas de mortalidade.

Blankaartia sinnamaryi (Trombidiformes: Trombiculidae) parasitizing birds in southeastern Brazil, with notes on Rickettsia detection / Blankaartia sinnamaryi (Trombidiformes: Trombiculidae) parasitando aves no sudeste do Brasil, e notas sobre a detecção de Rickettsia

Abstract The larvae of the family Trombiculidae are ectoparasites of vertebrates, including birds. The bite of some species can cause deep lesions and severe skin reactions in the host, these can lead to dermatitis, popularly known as trombiculiasis. A morphological study of chiggers collected on birds from the state of Minas Gerais in Southeastern Brazil discovered Blankaartia sinnamaryi-infestation on Passeriformes birds. Molecular studies of the disclosed the 18S rDNA sequences of the mite, and the detection of a Rickettsia sp. in this chigger mite species.

Resumo As larvas da família Trombiculidae são ectoparasitas de vertebrados, incluindo aves. A picada de algumas espécies pode causam lesões profundas e reações cutâneas graves no hospedeiro, estas podem levar a dermatites, popularmente conhecidas como trombiculíases. Por meio de um estudo morfológico dos espécimes coletados parasitando aves do estado de Minas Gerais, Sudeste do Brasil relatou a infestação por Blankaartia sinnamaryi em aves Passeriformes. Além disso, nós fornecemos sequências de rDNA 18S desses ácaros e a detecção de uma espécie de Rickettsia sp. nesta espécie de trombiculídeo.

In vitro efficacy of Duddingtonia flagrans against nematodes of sheep based on in vivo calculations / Eficácia in vitro de Duddingtonia flagrans contra nematoides de ovinos com base em cálculo in vivo

Abstract Duddingtonia flagrans has been tested as an alternative parasite control, but data from in vitro experiments based on in vivo calculations describing nematophagous fungi predation in nematodes are restricted. The objective of this work was to determine the efficacy of D. flagrans against sheep nematode larvae in vitro using in vivo calculations. Fecal samples were introduced to fungi in different concentrations: 0.0/control; 0.05; 0.1; 0.2; 0.4; 0.8; 1.6; 3.2; and 6.4 g corresponding, respectively, to 583.000; 1.166.000; 2.332.000; 4.664.000; 9.328.000; 18.656.000; 37.312.000 and 74.624.000 chlamydospores/kg of body weight. The material was incubated for 14 days, before the larvae recovery (Assay 1). Assay 2 was carried out with the doses of 0.00625; 0.0125; and 0.025 g. The results showed a negative correlation between fungal concentrations and larval numbers for both assays. The fungus demonstrated an efficacy above 89% in both assays. Thus, we consider that the data from in vitro studies based on in vivo calculations may optimize the fungi quantities for field experiments.

Resumo Duddingtonia flagrans tem sido testado como uma alternativa no controle de parasitos, entretanto, trabalhos in vitro da predação de nematoides por fungos nematófagos correlacionados com cálculos baseados para testes in vivo são restritos. O objetivo deste trabalho foi determinar a eficácia in vitro de D. flagrans contra larvas de nematoides de ovinos tendo como base cálculos in vivo. Amostras fecais receberam a adição do fungo em diferentes concentrações: 0.0/controle; 0,05; 0,1; 0,2; 0,4; 0,8; 1,6; 3,2 e 6,4 gramas correspondendo, respectivamente, às seguintes dosagens: 583.000; 1.166.000; 2.332.000; 4.664.000; 9.328.000; 18.656.000; 37.312.000 e 74.624.000 clamidósporos/Kg de peso vivo animal. O material foi incubado por 14 dias, para recuperação das larvas (Ensaio 1). O Ensaio 2 foi realizado com concentrações de 0,00625; 0,0125 e 0,025 g. Foi observada correlação negativa entre a concentração fúngica e o número de larvas, nos dois ensaios. O fungo demonstrou eficácia acima de 89% em ambos os ensaios. A partir destes dados, acreditamos que ensaios in vitro baseados em cálculos in vivo podem aprimorar as dosagens para a realização de experimentos a campo.

Enzymatic comparison and mortality of Beauveria bassiana against cabbage caterpillar Pieris brassicae LINN

Abstract Beauveria bassiana, an entomopathogenic fungus, is the alternative biocontrol agent exploited against major economic crop pests. Pieris brassicae L. is an emerging pest of the Brassicaceae family. Therefore, in the present study, fungal isolates of Beauveria bassiana, viz. MTCC 2028, MTCC 4495, MTCC 6291, and NBAII-11, were evaluated for their virulence against third instar larvae of P. brassicae. Among all these fungal isolates, maximum mortality (86.66%) was recorded in B. bassiana MTCC 4495 at higher concentration of spores (109 conidia/ml), and the minimum mortality (30.00%) was recorded in B. bassiana MTCC 6291 at a lower concentration (107 conidia/ml) after ten days of treatment. The extracellular cuticle-degrading enzyme activities of fungal isolates were measured. Variability was observed both in the pattern of enzyme secretion and the level of enzyme activities among various fungal isolates. B. bassiana MTCC 4495 recorded the maximum mean chitinase (0.51 U/ml), protease (1.12 U/ml), and lipase activities (1.36 U/ml). The minimum mean chitinase and protease activities (0.37 and 0.91 U/ml, respectively) were recorded in B. bassiana MTCC 6291. The minimum mean lipase activity (1.04 U/ml) was recorded in B. bassiana NBAII-11. Our studies revealed B. bassiana MTCC 4495 as the most pathogenic isolate against P. brassicae, which also recorded maximum extracellular enzyme activities, suggesting the possible roles of extracellular enzymes in the pathogenicity of B. bassiana against P. brassicae.

Infectivity of housefly, Musca domestica (Diptera: Muscidae) to different entomopathogenic fungi

Abstract The housefly Musca domestica is a worldwide insect pest that acts as a vector for many pathogenic diseases in both people and animals. The present study was conducted to evaluate the virulence of different local isolates of Beauveria bassiana, Metarhizium anisopliae and Isaria fumosorosea on M. domestica using two bioassay techniques: (1) adult immersion and (2) a bait method applied to both larvae and adults. The results showed evidence of a broad range of responses by both stages (larvae and adults) to the tested isolates of B. bassiana, M. anisopliae and I. fumosorosea. These responses were concentration-dependent, with mortality percentages ranging from 53.00% to 96.00%. Because it resulted in lower LC50 values and a shorter lethal time, B. bassiana (Bb-01) proved to be the most virulent isolate against both housefly larvae and adults. Sublethal doses of the tested isolates were also assessed to evaluate their effect on M. domestica fecundity and longevity. The fungal infections reduced housefly survival regardless of their sex and also decreased egg production in females.

Macelignan inhibits bee pathogenic fungi Ascophaera apis growth through HOG1 pathway

Ascosphaera apis is a bee pathogen that causes bee larvae infection disease, to which treatment is not yet well investigated. The aim of this study was to investigate antifungal susceptibility in vitro against A. apis and to identify a new antifungal agent for this pathogen through minimal inhibitory concentration (MIC) assay and western blot analysis. Macelignan had 1.56 and 3.125 μg/mL MIC against A. apis after 24 and 48 h, respectively, exhibiting the strongest growth inhibition against A. apis among the tested compounds (corosolic acid, dehydrocostus lactone, loganic acid, tracheloside, fangchinoline and emodin-8-O-β-D-glucopyranoside). Furthermore, macelignan showed a narrow-ranged spectrum against various fungal strains without any mammalian cell cytotoxicity. In spite of miconazole having powerful broad-ranged anti-fungal activity including A. apis, it demonstrated strong cytotoxicity. Therefore, even if macelignan alone was effective as an antifungal agent to treat A. apis, combined treatment with miconazole was more useful to overcome toxicity, drug resistance occurrence and cost effectiveness. Finally, HOG1 was revealed as a target molecule of macelignan in the anti-A. apis activity by inhibiting phosphorylation using S. cerevisiae as a model system. Based on our results, macelignan, a food-grade antimicrobial compound, would be an effective antifungal agent against A. apis infection in bees.

Preliminary screening of the larvicidal effect of Brevibacillus laterosporus strains against the blowfly Chrysomya megacephala(Fabricius, 1794) (Diptera: Calliphoridae)

: This study evaluated whether different strains of Brevibacillus laterosporus could be used to control larvae of the blowfly Chrysomya megacephala , a pest that affects both human and animal health.

Description of microsporidia in simulids: molecular and morphological characterization of microsporidia in the larvae of Simulium pertinax Kollar (Diptera: Simuliidae)

Introduction Microsporidia constitute the most common black fly pathogens, although the species' diversity, seasonal occurrence and transmission mechanisms remain poorly understood. Infections by this agent are often chronic and non-lethal, but they can cause reduced fecundity and decreased longevity. The objective of this study was to identify microsporidia infecting Simulium (Chirostilbia) pertinax (Kollar, 1832) larvae from Caraguatatuba, State of São Paulo, Brazil, by molecular and morphological characterization. Methods Larvae were collected at a single point in a stream in a rural area of the city and were kept under artificial aeration until analysis. Polydispyrenia spp. infection was characterized by the presence of at least 32 mononuclear spores measuring 6.9 ± 1.0 × 5.0 ± 0.7µm in persistent sporophorous vesicles. Similarly, Amblyospora spp. were characterized by the presence of eight uninucleate spores measuring 4.5 × 3.5µm in sporophorous vesicles. Results The molecular analysis confirmed the presence of microsporidian DNA in the 8 samples (prevalence of 0.51%). Six samples (Brazilian larvae) were related to Polydispyrenia simulii and Caudospora palustris reference sequences but in separate clusters. One sample was clustered with Amblyospora spp. Edhazardia aedis was the positive control taxon. Conclusions Samples identified as Polydispyrenia spp. and Amblyospora spp. were grouped with P. simulii and Amblyospora spp., respectively, corroborating previous results. However, the 16S gene tree showed a considerable distance between the black fly-infecting Amblyospora spp. and the mosquito-infecting spp. This distance suggests that these two groups are not congeneric. Additional genomic region evaluation is necessary to obtain a coherent phylogeny for this group. .

Antifungal activity of Stenotrophomonas maltophilia in Stomoxys calcitrans larvae / Atividade antifúngica de Stenotrophomonas maltophilia em larvas de Stomoxys calcitrans

The microbiota present in Stomoxys calcitrans larvae may assist their survival in contaminated environments through production of inhibitory substances. Bacteriological identification methods, the polymerase chain reaction (PCR) and scanning electron microscopy (SEM) were used to detect a bacterium naturally present in mucus and macerated S. calcitrans larvae. The antifungal activity was determined based on the results from disk diffusion tests on an artificial solid medium. The bacterium was identified as Stenotrophomonas maltophilia and presented antifungal activity against Beauveria bassiana sensu lato isolates CG 138, CG 228 and ESALQ 986. This result suggests that the larval microbiota is a factor that can compromise the use of B. bassiana s.l. fungus for biological control of S. calcitrans larvae.

A microbiota presente em larvas de Stomoxys calcitrans pode auxiliar na sua sobrevivência em ambientes contaminados, devido à produção de substâncias inibidoras. Métodos bacteriológicos de identificação, reação em cadeia da polimerase (PCR) e microscopia eletrônica de varredura (MEV) foram utilizados para detectar uma bactéria naturalmente presente no muco e macerado de larvas de S. calcitrans. A atividade antifúngica foi baseada nos resultados obtidos no teste de difusão em meio sólido artificial. A bactéria foi identificada como Stenotrophomonas maltophilia e apresentou atividade antifúngica contra os isolados CG 138, CG 228 e ESALQ 986 de Beauveria bassiana sensu lato. Estes resultados sugerem que a microbiota larval é um fator que pode comprometer o uso de B. bassiana s.l. no controle biológico de larvas de S. calcitrans.

Larval Chigger Mites Collected from Small Mammals in 3 Provinces, Korea

A total of 9,281 larval chigger mites were collected from small mammals captured at Hwaseong-gun, Gyeonggi-do (Province) (2,754 mites from 30 small mammals), Asan city, Chungcheongnam-do (3,358 mites from 48 mammals), and Jangseong-gun, Jeollanam-do (3,169 for 62 mammals) from April-November 2009 in the Republic of Korea (= Korea) and were identified to species. Leptotrombidium pallidum was the predominant species in Hwaseong (95.8%) and Asan (61.2%), while Leptotrombidium scutellare was the predominant species collected from Jangseong (80.1%). Overall, larval chigger mite indices decreased from April (27.3) to June (4.9), then increased in September (95.2) and to a high level in November (169.3). These data suggest that L. pallidum and L. scutellare are the primary vectors of scrub typhus throughout their range in Korea. While other species of larval chigger mites were also collected with some implications in the transmission of Orientia tsutsugamushi, they only accounted for 11.2% of all larval chigger mites collected from small mammals.

Ecoepidemiología de la infección por rickettsias en roedores, ectoparásitos y humanos en el noroeste de Antioquia, Colombia / Ecoepidemiology of rickettsial infection in rodents, ectoparasites and humans in northeastern Antioquia, Colombia

Introducción. Las rickettsias son bacterias patógenas usualmente transmitidas por ectoparásitos, como garrapatas, piojos o pulgas. En la última década se presentaron tres brotes de rickettsiosis con casos fatales en la región noroccidental de Antioquia y en un municipio limítrofe de Córdoba. Objetivo. Describir la ecología y la epidemiología de las infecciones por Rickettsia spp. en el Urabá antioqueño. Materiales y métodos. Se obtuvieron muestras de 354 roedores y se recolectaron 839 ectoparásitos de estos en los municipios de Apartadó, Turbo y Necoclí. Asimismo, se obtuvieron 220 sueros humanos. Estas muestras fueron estudiadas por reacción en cadena de la polimerasa (PCR) e inmunofluorescencia indirecta (IFI) para la detección de infección por rickettsias. Resultados. Por IFI se detectaron anticuerpos antirickettsias en 130 (43 %) de los roedores y en 53 (24 %) de los sueros humanos estudiados. Además, se amplificaron secuencias del gen gltA específicas del género Rickettsia en 23 (6,8 %) muestras de hígado de roedores, las cuales mostraron una similitud del 98,7 % con R. prowazekii . Una secuencia de gltA obtenida de larvas de garrapatas del género Amblyomma sp., tuvo una identidad mayor de 99 % con las secuencias de R. tamurae . Conclusión. Estos resultados demuestran la circulación de rickettsias en roedores, ectoparásitos y humanos en los municipios estudiados.

Introduction: Rickettsia spp. are tick, flea or lice-borne pathogenic bacterium, usually carried by rodents. In the last decade three outbreaks of rickettsial disease including fatalities, occurred in the provinces of Antioquia and Córdoba in northwestern Colombia. Objective: The purpose of this study was to perform an ecological and epidemiological description of the Rickettsia spp infection in the recently affected region of Colombia. Materials and methods: Samples were obtained from 354 rodents and their parasites captured in the municipalities of Apartadó, Turbo and Necoclí. Likewise, 220 human sera were also collected, for detection of infection by Rickettsia spp. Results: Indirect immunofluorescence assay (IFA) revealed that 130 (43%) of the rodents and 53 (24%) of the humans produced antibodies to Rickettsia spp. Additionally, rickettsial DNA was amplified by PCR from 23 (6.8%) rodent liver samples using primers directed to the genus specific gltA gene. While gltA sequences from rodent samples exhibited a 98.7% similitude with R . prowazekii, a sequence amplified from larvae of Amblyomma sp exhibited identities of >99% similarity with R. tamurae . Conclusion: These results demonstrate the presence of rickettsia in rodents, ectoparasites and humans throughout the municipalities studied.

In vitro predatory activity of conidia of fungal isolates of the Duddingtonia flagrans on Angiostrongylus vasorum first-stage larvae

INTRODUCTION:Angiostrongylus vasorum is a nematode that parasitizes molluscs, dogs, and even man. METHODS:The objective was to evaluate the predatory activity of the conidia of two fungal isolates of Duddingtonia flagrans (AC001 and CG722) on first-stage larvae (L1) of A. vasorum in laboratory conditions. RESULTS: At the end of the experiment, there were significant reductions (p<0.01) of 74.5% and 63.2%, on average, in the A. vasorum (L1) recovered in the AC001 and CG722 treatment conditions, respectively. CONCLUSIONS: The two isolates of fungi were efficient in the capture and destruction of A. vasorum (L1).

Body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles, depigmentation of mouthparts, and presence of Batrachochytrium dendrobatidis are related / Tamanho do corpo, despigmentação das partes bucais e presença de Batrachochytrium dendrobatidis estão relacionados em Hylodes cf. ornatus e Lithobates catesbeianus

A fungal pathogen Batrachochytrium dendrobatidis (Bd), which can cause morbidity and death of anurans, has affected amphibian populations on a worldwide basis. Availability of pure cultures of Bd isolates is essential for experimental studies to understand the ecology of this pathogen. We evaluated the relationships of body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles to depigmentation of mouthparts and determined if dekeratinization indicated an infection by Batrachochytrium dendrobatidis. A strong association existed for both species, one from South America (Brazil: São Paulo) and one from North America (USA: Maine). We believe it prudent not to kill adult amphibians if avoidable, thus obtaining tissue for isolating Bd from tadpoles is reasonable because infected specimens of some species can be selectively collected based on depigmentation of mouthparts.

O fungo patógeno Batrachochytrium dendrobatidis (Bd) é apontado como o causador de morbidade e morte em anuros, e tem afetado populações de anfíbios em uma base mundial. Avaliar culturas puras de isolados de Bd é essencial para estudos experimentais para o entendimento da ecologia desse patógeno. Avaliou-se a relação entre o comprimento do corpo em girinos de Hylodes cf. ornatus e Lithobates catesbeianus com a despigmentação das peças bucais, para verificar se a desqueratinização indica uma infecção por Batrachochytrium dendrobatidis. Uma forte associação existe para ambas as espécies, uma da América do Sul (Brasil: São Paulo) e uma da América do Norte (USA: Maine). Acredita-se ser prudente este uso, para evitar a morte de anfíbios adultos; dessa forma, obter tecidos para isolar o Bd de girinos é razoável, porque espécimes infectados podem ser coletados seletivamente com base na despigmentação do aparelho bucal.

Antagonistic effects of symbiotic bacteria isolated from midgut of honey bee workers against Ascosphaera apis, the causal pathogen of chalkbrood disease

Six biotypes of fungal isolates belonging to Ascosphaera apis were isolated by three media from infested honey bee larvae. Two isolates [A[7] and A[15]] were able to form sporocysts. However, the other four [A[3], A[4], A[8],A[9]] did not form sporocyts on cultivated Murashieg and Skoog medium [mMS]. Six isolates from symbiotic bacteria associated with midgut of honey bee workers have been insolated from healthy workers. Four isolates from endospore-forming bacteria belonged to Bacillus subtilis [B[2], B[4], B[10] and B[100]] and two isolates from non endospore-forming bacteria to Pseudomonas fluorescence [P[1[and P[5]] were isolated. Morphological features and physiological reactions of isolated bacteria were determined. Antagonistic effectiveness of both Bacillus subtilis and Pseudomonas fluorescence was tested against isolates of Ascosphaera apis, the causal pathogen of chalkbrood disease, in vitro. Data showed that Bacillus subtills isolate [B2], gave the highest antagonistic effect as inhibition zone and mycelial growth followed by Pseudomonas fluorescence [P[1]]. Highly significant differences among Bacillus subtilis [B[2]], Pseudomonas fluorescence [P[1]] and other bacterial strains were recorded.. Scanning electron microscope was used to examined the fungal hyphae and mature sporocysts of Ascosphaera apis which isolated from infested larvae and grown on [mMs]. Numerous distinguish differences were recorded. The examination showed that numerous bacterial cells of Pseudomonas fluorescence invaded fungal hyphae of Ascosphaera apis and caused disintegration the cell walls. Whereas Bacillus subtilis hyphae showed shrinking appearance. It could be conducted that such symbiotic bacteria can considered as a bioformula for controlling such disease in honey bee colonies

Characterization of Bacillus thuringiensis soil isolates from Cuba, with insecticidal activity against mosquitoes

Chemical insecticides may be toxic and cause environmental degradation. Consequently, biological control for insects represents an alternative with low ecological impact. In this work, three soil isolates (A21, A51 and C17) from different regions of the Cuban archipelago were identified, characterized and evaluated against Aedes aegypti and Culex quinquefasciatus. The new isolates were compared with reference IPS82 strain and two strains isolated from biolarvicides Bactivec and Bactoculicida, respectively. The differentiation was done by morphological, biochemical, bioassays activity and molecular methods (SDS-PAGE, plasmid profile and random amplified polymorphic analysis). All isolates were identified as Bacillus thuringiensis. The A21, A51 and C17 isolates showed higher larvicide activity than Bactivec’s isolated reference strain, against both A. aegypti and C. quinquefasciatus. A21 isolate had a protein profile similar to IPS82 and Bactivec strain. A51 and C17 isolates produced a characteristic proteins pattern. A21 and A51 isolates had plasmid patterns similar to IPS82 standard strain, while C17 isolate had different both plasmid profile and protein bands. All the studied isolates showed a diverse RAPD patterns and were different from the strains previously used in biological control in Cuba. Rev. Biol. Trop. 59 (3): 1007-1016. Epub 2011 September 01.

El uso prolongado de insecticidas ha conducido al desarrollo de resistencia en diferentes especies de mosquitos y al incremento de la degradación del ambiente. El control biológico de insectos ha devenido como una alternativa útil y de bajo impacto ambiental. En nuestro estudio fueron identificados, caracterizados tres aislamientos de suelos procedentes de diferentes regiones del archipiélago cubano y comparados con cepas de referencia: aisladas de los biolarvicidas Bactivec y Bactoculicida, además de IPS82. La diferenciación de los mismos se llevó a cabo mediante métodos morfológicos, bioquímicos y moleculares (SDSPAGE, perfil plasmídico, RAPD). Los aislamientos fueron identificados como Bacillus thuringiensis; A21, A51 y C17 mostraron una mayor actividad contra larvas de Aedes aegypti and Culex quinquefasciatus que la cepa aislada del biolarvicida Bactivec, utilizada como referencia en este estudio. Dos de los aislamientos poseían perfiles proteicos y plasmídicos similares al de la cepa control IPS82, pero el restante difería de ellos. Los tres mostraron patrones de RAPD diferentes lo que nos permitió su diferenciación. Estos patrones de RAPD también diferían del observado para las cepas utilizadas comúnmente en el control biológico en nuestro país.

Atividade larvicida do extrato bruto enzimático do fungo Duddingtonia flagras sobre larvas de primeiro estádio de Angiostrongylus vasorum / Larvicidal activity of a crude enzyme extract of the fungus Duddingtonia flagrans on first-stage larvae of Angiostrongylus vasorum

INTRODUÇÃO: Angiostrongylus vasorum é um nematóide que parasita cães domésticos e eventualmente o homem. MÉTODOS: O objetivo deste trabalho foi observar a atividade predatória in vitro do extrato bruto enzimático do fungo Duddingtonia flagrans sobre larvas de primeiro estádio A. vasorum em condições laboratoriais no meio ágar-água 2 por cento. RESULTADOS: Ao final do experimento, os percentuais de redução das L1 de A. vasorum observados foram de: 53,5 por cento (24h) e 71,3 por cento (48h) CONCLUSÕES: O extrato bruto enzimático do fungo D. flagrans destruiu in vitro as L1, podendo ser utilizado como controle biológico desse nematóide.

INTRODUCTION: Angiostrongylus vasorum is a nematode parasite of domestic dogs and potentially of humans. METHODS: This study aimed to observe the predatory activity in vitro of a crude enzyme extract of the fungus Duddingtonia flagrans on first-stage larvae of A. vasorum in laboratory conditions on 2 percent water-agar. RESULTS: At the end of the experiment, the percentage reductions observed for A. vasorum L1 were 53.5 percent (24h) and 71.3 percent (48h). CONCLUSIONS: Crude enzyme extract of the fungus D. flagrans destroyed the L1 in vitro and can be used as a biological control for this nematode.

Destruição de larvas infectantes de Strongyloides venezuelensis pelos fungos Duddingtonia flagrans, Arthrobotrys robusta e Monacrosporium sinense / Destruction of Strongyloides venezuelensis infective larvae by fungi Duddingtonia flagrans, Arthrobotrys robusta and Monacrosporium sinense

INTRODUÇÃO: Strongyloides venezuelensis tem sido utilizado como um modelo para estudo da estrongiloidose humana. MÉTODOS: O objetivo deste trabalho foi comparar a capacidade predatória dos fungos nematófagos Duddingtonia flagrans (AC001), Arthrobotrys robusta (I-31) e Monacrosporium sinense (SF53) sobre larvas infectantes (L3) de Strongyloides venezuelensis em condições laboratoriais no meio ágar-água 2 por cento. RESULTADOS: Ao final do experimento, os percentuais de redução de L3 de Strongyloides venezuelensis observados foram de: 93 por cento (AC001); 77,2 por cento (I-31) e 65,2 por cento (SF53). CONCLUSÕES: Os fungos nematófagos foram capazes de capturar e destruir in vitro as L3, podendo ser utilizados como controladores biológicos de Strongyloides venezuelensis.

INTRODUCTION: Strongyloides venezuelensis has been used as a model for studying human strongyloidosis. METHODS: This study aimed to compare the ability of predatory nematophagous fungi Duddingtonia flagrans (AC001), Arthrobotrys robusta (I-31) and Monacrosporium sinense (SF53) and on infective larvae (L3) of Strongyloides venezuelensis in laboratory conditions on 2 percent water-agar medium. RESULTS: At the end of the experiment, the percentage reductions of Strongyloides venezuelensi L3 were: 93 percent (AC001), 77.2 percent (I-31) and 65.2 percent (SF53). CONCLUSIONS: The nematophagous fungi were able to capture and destroy the L3 in vitro and can be used as biological controllers of Strongyloides venezuelensi.

Atividade predatória dos fungos nematófagos Duddingtonia flagrans, Monacrosporium thaumasium e Artrobotrys robusta sobre larvas infectantes de Strongyloides stercoralis / Predatory activity of the nematophagous fungi Duddingtonia flagrans, Monacrosporium thaumasium and Arthrobotrys robusta on Strongyloides stercoralis infective larvae

INTRODUÇÃO: Strongyloides stercoralis é um nematoide que infecta grande parte da população mundial. MÉTODOS: O objetivo deste trabalho foi comparar a capacidade predatória dos fungos nematófagos Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34) e Arthrobotrys robusta (I-31) sobre larvas infectantes (L3) de Strongyloides stercoralis em condições laboratoriais no meio ágar-água 2 por cento. RESULTADOS: Ao final do experimento, os percentuais de redução de L3 de Strongyloides stercoralis observados foram de: 83,7 por cento (AC001); 75,5 por cento (NF34) e 73,2 por cento (I-31). CONCLUSÕES: Os fungos nematófagos foram capazes de capturar e destruir in vitro as L3, podendo ser utilizados como controladores biológicos de Strongyloides stercoralis.

INTRODUCTION: Strongyloides stercoralis is a nematode that infects much of the population worldwide. METHODS: This study aimed to compare the ability of predatory nematophagous fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34) and Arthrobotrys robusta (I-31) on infective larvae (L3) of Strongyloides stercoralis in laboratory conditions on 2 percent water-agar. RESULTS: At the end of the experiment, the percentage reductions in Strongyloides stercoralis L3 were 83.7 percent (AC001), 75.5 percent (NF34) and 73.2 percent (I-31). CONCLUSIONS: The nematophagous fungi were able to capture and destroy the L3 in vitro and may be used as biological controls of Strongyloides stercoralis.