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Context: Pyocyanin is a typical Pseudomonas aeruginosa virulence factor, a common Gram-negative rod responsible for a wide range of severe nosocomial infections. There is evidence indicating that pyocyanin has multiple biological activities, but little is known about anti-inflammatory properties. Objective: This study investigated pyocyanin effect on nitric oxide and cytokine production in lipopolysaccharide (LPS)-activated murine peritoneal macrophages. Materials and methods: Macrophages were incubated in the presence and absence of pyocyanin (1, 5, 10, 50, and 100 µM) with and without LPS (1 µg/mL). Nitric oxide production was determined by Griess reagent and tumor necrosis factor (TNF)-α and interleukin (IL)-1ß production was assessed by enzyme-linked immunosorbent assay. In addition, pyocyanin effects on zymosan A-induced peritonitis in mice were evaluated. Results: Pyocyanin (5 and 10 µM) decreased nitric oxide, TNF-α, and IL-1ß production independent of macrophage death. On the other hand, in vivo, pyocyanin (5 mg/kg) was not able to affect leukocyte migration into the site of inflammation. Discussion and conclusion: Thus, our findings suggest that pyocyanin exerts anti-inflammatory effects on murine peritoneal macrophages, downregulating nitric oxide, TNF-α, and IL-1ß levels, which seems to be independent of cell migration. These effects may represent a mechanism of immune evasion; nevertheless more detailed studies should be performed to confirm this hypothesis.

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Cancer results from a complex interplay of different biological, chemical, and physical phenomena that span a wide range of time and length scales. Computational modeling may help to unfold the role of multiple evolving factors that exist and interact in the tumor microenvironment. Understanding these complex multiscale interactions is a crucial step towards predicting cancer growth and in developing effective therapies. We integrate different modeling approaches in a multiscale, avascular, hybrid tumor growth model encompassing tissue, cell, and sub-cell scales. At the tissue level, we consider the dispersion of nutrients and growth factors in the tumor microenvironment, which are modeled through reaction-diffusion equations. At the cell level, we use an agent based model (ABM) to describe normal and tumor cell dynamics, with normal cells kept in homeostasis and cancer cells differentiated apoptotic, hypoxic, and necrotic states. Cell movement is driven by the balance of a variety of forces according to Newton's second law, including those related to growth-induced stresses. Phenotypic transitions are defined by specific rule of behaviors that depend on microenvironment stimuli. We integrate in each cell/agent a branch of the epidermal growth factor receptor (EGFR) pathway. This pathway is modeled by a system of coupled nonlinear differential equations involving the mass laws of 20 molecules. The rates of change in the concentration of some key molecules trigger proliferation or migration advantage response. The bridge between cell and tissue scales is built through the reaction and source terms of the partial differential equations. Our hybrid model is built in a modular way, enabling the investigation of the role of different mechanisms at multiple scales on tumor progression. This strategy allows representating both the collective behavior due to cell assembly as well as microscopic intracellular phenomena described by signal transduction pathways. Here, we investigate the impact of some mechanisms associated with sustained proliferation on cancer progression. Specifically, we focus on the intracellular proliferation/migration-advantage-response driven by the EGFR pathway and on proliferation inhibition due to accumulation of growth-induced stresses. Simulations demonstrate that the model can adequately describe some complex mechanisms of tumor dynamics, including growth arrest in avascular tumors. Both the sub-cell model and growth-induced stresses give rise to heterogeneity in the tumor expansion and a rich variety of tumor behaviors.

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O cupim asiático Coptotermes gestroi é considerado praga em áreas urbanas, causando danos expressivos em casas, edifícios e árvores. Esta pesquisa avaliou a eficiência de Isaria javanica URM4993 e I. javanica URM4995 sobre operários de C. gestroi. Os insetos foram pulverizados nas concentrações de 104 a 108 conídios/mL e mantidos em incubadora a 25 ± 1º C e 80 ± 10% de umidade relativa. Determinou-se a Concentração Letal (CL50) e o Tempo Letal (TL50), bem como foi quantificada a produção de conídios sobre os insetos mortos. Os aspectos biológicos referentes à germinação e esporulação, antes e após a infecção em C. gestroi, foram avaliados. O fungo foi virulento ao cupim, causando infecção em todas as concentrações utilizadas, sendo que I. javanica URM4993 foi mais eficiente, por causar mortalidade de 100%, após o 6º dia de inoculação (CL50 de 4,86 conídios/mL e TL50 de 2,26 dias). A esporulação nos insetos mortos não diferiu entre as linhagens. Foi observado que o percentual de germinação foi maior nas linhagens reisoladas do que nas linhagens padrão. Contudo, I. javanica URM4993 apresentou maior potencial de esporulação. Esses resultados mostram o fungo como um candidato ao controle biológico desse cupim.

The Asiatic termite Coptotermes gestroi is considered a pest in urban areas causing extensive damage to houses, buildings and trees. The present study evaluated the effectiveness of Isaria javanica URM4993 and URM4995 on workers of C. gestroi. Insects were sprayed with concentrations of 104 at 108 conidia/mL and kept in an incubator at 25 ± 1º C and 80 ± 10% relative humidity. Results were used to determine the lethal concentration (LC50) and lethal time (LT50). Conidia production on dead insects was assessed. Biological aspects related to germination and sporulation, before and after infection with C. gestroi were also assessed. The fungus was virulent to termites, causing infection at all tested concentrations, with I. javanica URM4993 being the most virulent, causing 100% mortality after six days of inoculation (LC50 of 4.86 x 10 conidia/mL and LT50 of 2.26 days). Sporulation on dead insects did not differ between strains. The percentage of germination was greater for reisolated strains than for standard strains. However, I. javanica URM4993 showed greater sporulation. These results show that the fungus is a candidate for the biological control of termites.

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Isolates of entomopathogenic fungus Metarhizium anisopliae var. anisopliae were characterized using internal transcribed spacer-RFLP, ISSR and intron splice site primers. Thirty-seven isolates were studied, most of which were obtained from the sugar cane pest, Mahanarva fimbriolata (Hemiptera: Cercopidae) from Tangará da Serra, Southwest Mato Grosso State, Brazil. Internal transcribed spacer-RFLP did not differentiate the isolates of M. anisopliae var. anisopliae, while ISSR and intron primers identified three distinct groups. Variability among these groups was 96% for (GTG)(5) and 100% for the other primers. We found considerable genetic variability, even among isolates from the same geographical origin and host.

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Onion anthracnose, caused by Colletotrichum gloeosporioides, is one of the main diseases of onions in the State of Pernambuco. We examined the pathogenicity of 15 C. gloeosporioides strains and analyzed their genetic variability using RAPDs and internal transcribed spacers (ITS) of the rDNA region. Ten of the strains were obtained from substrates and hosts other than onion, including chayote (Sechium edule), guava (Psidium guajava), pomegranate (Punica granatum), water from the Capibaribe River, maracock (Passiflora sp), coconut (Cocus nucifera), surinam cherry (Eugenia uniflora), and marine soil; five isolates came from onions collected from four different regions of the State of Pernambuco and one region of the State of Amazonas. Pathogenicity tests were carried out using onion leaves and bulbs. All strains were capable of causing disease in leaves, causing a variable degree of lesions on the leaves; four strains caused the most severe damage. In the onion bulb tests, only three of the above strains caused lesions. Seven primers of arbitrary sequences were used in the RAPD analysis, generating polymorphic bands that allowed the separation of the strains into three distinct groups. The amplification products generated with the primers ITS1 and ITS4 also showed polymorphism when digested with three restriction enzymes, DraI, HaeIII and MspI. Only the latter two demonstrated genetic variations among the strains. These two types of molecular markers were able to differentiate the strain from the State of Amazonas from those of the State of Pernambuco. However, there was no relationship between groups of strains, based on molecular markers, and degree of pathogenicity for onion leaves and bulbs.

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ABSTRACT The Asiatic termite Coptotermes gestroi is considered a pest in urban areas causing extensive damage to houses, buildings and trees. The present study evaluated the effectiveness of Isaria javanica URM4993 and URM4995 on workers of C. gestroi. Insects were sprayed with concentrations of 104 at 108 conidia/mL and kept in an incubator at 25 ± 1º C and 80 ± 10% relative humidity. Results were used to determine the lethal concentration (LC50) and lethal time (LT50). Conidia production on dead insects was assessed. Biological aspects related to germination and sporulation, before and after infection with C. gestroi were also assessed. The fungus was virulent to termites, causing infection at all tested concentrations, with I. javanica URM4993 being the most virulent, causing 100% mortality after six days of inoculation (LC50 of 4.86 x 10 conidia/mL and LT50 of 2.26 days). Sporulation on dead insects did not differ between strains. The percentage of germination was greater for reisolated strains than for standard strains. However, I. javanica URM4993 showed greater sporulation. These results show that the fungus is a candidate for the biological control of termites.

RESUMO O cupim asiático Coptotermes gestroi é considerado praga em áreas urbanas, causando danos expressivos em casas, edifícios e árvores. Esta pesquisa avaliou a eficiência de Isaria javanica URM4993 e I. javanica URM4995 sobre operários de C. gestroi. Os insetos foram pulverizados nas concentrações de 104 a 108 conídios/mL e mantidos em incubadora a 25 ± 1º C e 80 ± 10% de umidade relativa. Determinou-se a Concentração Letal (CL50) e o Tempo Letal (TL50), bem como foi quantificada a produção de conídios sobre os insetos mortos. Os aspectos biológicos referentes à germinação e esporulação, antes e após a infecção em C. gestroi, foram avaliados. O fungo foi virulento ao cupim, causando infecção em todas as concentrações utilizadas, sendo que I. javanica URM4993 foi mais eficiente, por causar mortalidade de 100%, após o 6º dia de inoculação (CL50 de 4,86 conídios/mL e TL50 de 2,26 dias). A esporulação nos insetos mortos não diferiu entre as linhagens. Foi observado que o percentual de germinação foi maior nas linhagens reisoladas do que nas linhagens padrão. Contudo, I. javanica URM4993 apresentou maior potencial de esporulação. Esses resultados mostram o fungo como um candidato ao controle biológico desse cupim.

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Members of the Fusarium solani species complex are agents of human mycoses, also affecting plants and other animals. Nevertheless, this fungus has not been reported on scorpions. Ten specimens of Tityus stigmurus collected in the field and showing their surface covered by white mycelia were used to assess fungus presence in the animal after its death. Identification of the fungi was based upon the cultural and morphological characteristics. The fungus was isolated from chelicerae and intersegmental regions. Infected individuals had their behaviour modified by reducing feeding and locomotion. None of the infected individuals survived. It is likely that this fungus may have a role in the regulation of field scorpion populations.

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The Aspergillus genus belongs to a filamentous fungal group characterized by wide dispersion in the environment. Some species are associated with diseases, especially in immunocompromised patients, while others are of economical importance due to aflatoxin production or biotechnological applications. Its species identification is nowadays performed by traditional techniques combined with molecular markers, resulting in a higher efficiency of isolate characterization. In the present study, internal transcribed spacer, inter-simple sequence repeats (ISSR), and random amplified polymorphic DNA (RAPD) molecular markers were used, with the aim of genetically characterizing strains of Aspergillus flavus and strains of other species of the A. flavus group. High genetic diversity was revealed by RAPD and by ISSR, in which the use of the (GACA)4 primer yielded a higher diversity than with the (GTG)5 primer, although the latter showed a characteristic banding profile for each species. These data were used to create a similarity matrix for the construction of dendrograms by means of the UPGMA method. The ISSR and RAPD profiles showed that among the strains previously identificated as A. flavus, one should be A. oryzae, one A. parasiticus and two A. tamarii. On the other hand, a strain previously identified as A. parasiticus should be A. flavus. All these strains were retested by traditional methods and their new species identification was confirmed. These results strongly support the need for using molecular markers as an auxiliary tool in differentiating fungal species and strains.

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ABSTRACT Investigations concerning pathogenicity require basic knowledge in the biology and ecology of the target species involved in the study. The present work describes a technique to maintain the termite Nasutitermes coxipoensis under laboratory conditions to conduct tests with entomopathogenic fungi. The termites were maintained in plastic boxes with a piece of the original nest (20 g) and different food substrates: rotting wood, dry wood, sugarcane pulp, and wood paper. The survival function S(t) was applied to determine the best substrate for maintaining the termites under laboratory conditions, considering an ending time for the experiment of 18 days (t). The results indicated the sugarcane pulp, followed by wood paper as the best substrates for maintaining N. coxipoensis. This information will open opportunities for studies with termites under laboratory conditions.

RESUMO Pesquisas sobre patogenicidade necessitam de conhecimentos básicos em biologia e ecologia dos organismos envolvidos no estudo. O presente trabalho descreve uma técnica de manutenção do cupim Nasutitermes coxipoensis em condições de laboratório a fim de realização de testes com fungos entomopatogênicos. Os cupins foram mantidos em caixas plásticas contendo pedaço de ninho (20 g) e substratos alimentares diferentes: madeira em decomposição, madeira seca, colmo de cana-de-açúcar e papel madeira. Utilizou-se a função de sobrevivência S(t) com o objetivo de verificar a probabilidade de vida dos insetos até um tempo t (18 dias), a fim de mantê-los em condições de laboratório. Os resultados indicaram que o substrato que possibilitou maior tempo de sobrevivência foi cana-de-açúcar, seguido de papel madeira picado. Tais informações possibilitarão a realização de testes diversos com cupins, em condições de laboratório.

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ABSTRACT The objective this research was to evaluate the behavior of Beuveria bassiana Balsamo Vuillemin fungus reisolated from different phases of development of Chrysomya albiceps. The fungus B. bassiana was isolated originally from Castnia licus Drury (Lepidoptera: Castniidae), and kept at the Culture Collection (Micoteca-URM) of the Department of Mycology of the Universidade Federal de Pernambuco, under the access number 3,447. The experiment was carried out under artificial conditions at 60 ± 10% relative humidity and 27 ± 1o C. The percentile of germination was elevated, with the largest index observed in the reisolate from the larval phase; the radial growth in the interval of stipulated time was satisfactory, the conidia number on the 12th day for the reisolate from the adult phase was larger than that for the reisolate from the egg phase. The number of colonies of all the reisolates was higher than that of the control. Differences were not observed in the cytological aspects of the life cycle of B. bassiana after passage in eggs, larvae and adults.

RESUMO O objetivo desta pesquisa foi avaliar o comportamento do fungo Beauveria bassiana Balsamo Vuillemin reisolado de diferentes fases de desenvolvimento de Chrysomya albiceps. O fungo B. bassiana foi originalmente isolado de Castnia licus Drury (Lepidoptera: Castniidae), e está depositado na Coleção de Cultura (Micoteca-URM) do Departamento de Micologia da Universidade Federal de Pernambuco, sob o número de acesso 3.447. O experimento foi realizado em condições artificiais sob umidade e temperatura 60 ± 10% e 27 ± 1o C, respectivamente. O percentual de germinação foi elevado, com o maior índice observado no reisolado de larva; o crescimento radial no intervalo de tempo estipulado foi satisfatório, o número de conídios no 12o dia do reisolado de adulto foi maior do que o reisolado de ovo. O número de colônias de todos os reisolados foi superior ao controle. Não foram observadas diferenças nos aspectos citológicos do ciclo de vida de B. bassiana pós-passagem em ovos, larvas e adultos.

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O objetivo deste trabalho foi demonstrar por meio de um caso clínico as possibilidades de tratamento e eliminação de sintomas de Disfunção Temporomandibular utilizando-se de recursos fisioterapêuticos e treino de postura; com tratamento interdisciplinar entre o fisioterapeuta e o odontólogo. Paciente, sexo feminino, 19 anos, portadora de Disfunção Temporomandibular sob tratamento odontológico com splint interoclusal, foi submetida a tratamento fisioterapêutico. Foi realizado exame clínico odontológico, sendo avaliados os seguintes itens: queixa principal; presença de doença sistêmica; máxima abertura bucal; estalido da ATM; presença de desgaste dental; presença de um quadro de estresse do paciente; tratamento ortodôntico prévio; palpação da musculatura mastigatória e região retrocondilar. Classificação da intensidade da dor. A coleta de dados para a avaliação fisioterap~eutica foi realizada mediante exame clínico da paciente, que constou de anamnese, avaliação física e análise funcional. A dor na ATM e região cervical foram eliminadas, os trigger points foram desativados, a cabeça melhor posicionada com diminuição da protusão cervical, o ombro esquerdo sofreu leve elevação, aumento da flexibilidade da coluna cervical, a assimetria dos olhos e mandíbula não ofreram influência com o tratamento proposto. Os resultados sugerem que o uso de placa como forma única de tratamento não é suficiente para manter a coordenação muscular; é imprescindível um tratamento interdisciplinar entre o fisioterapeuta e o odontólogo, a fim de que o paciente seja analisado visando o equilíbrio de sua biomecânica, sua relação com a coluna cervical e postura, para a obtenção de resultados mais satisfatórios quando essas alterações apresentarem diante desses profissionaisa.

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RESUMO Beauveria bassiana (Bals.) Vuill. (URM 3447) isolado de Castnia licus (Drury) e reisolado de ovos, larvas e adultos de Anthonomusgrandis (bicudo-do-algodoeiro), artificialmente infectado, foi avaliado sob condições (temperatura: 27 ± 2º C, UR: 60 ± 10% e fotofase: 14h). Estimou-se a viabilidade de B. bassiana (germinação, crescimento colonial e conidiogênese) em meio de cultura Batata-Dextrose-Ágar (BDA) e virulência ao inseto adulto. Conídios em suspensão aquosa com Tween 80 (0,05%), nas concentrações (0,62 x 106; 0,24 x 106 e 0,43 x 106 conídios/mL), constituíram os inóculos para os testes de viabilidade e virulência. Determinou-se a taxa de germinação para o fungo reisolado e não reisolado, 18h após a inoculação. Crescimento das colônias e conidiogênese foram estimados nos intervalos de 3, 6, 9, 12 e 15 dias. As suspensões de conídios nas concentrações aplicadas causaram mortalidade de 96,7, 83,4 e 91,1% em TL de 5,4, 5,9 e 5,3 dias, respectivamente. Verificou-se que B. bassiana (URM-3447), reisolado de ovos, larvas e adultos de A. grandis , apresentou elevada viabilidade de germinação, crescimento colonial e conidiogênese em meio BDA, podendo ser produzido e empregado como agente de controle do inseto.

ABSTRACT Beauveria bassiana (Bals.) Vuill. (URM 3447) isolated from Castnia licus (Drury) and reisolated from eggs, larvae and adults of Anthonomus grandis (boll weevil), infected artificially was evaluated under various conditions (temperature: 27 ± 2º C, HR: 60 ± 10% and photophase: 14h). Estimation was made of the viability of B. bassiana (germination, colonial growth and conidiogenesis) in Potato-Dextrose-Agar (PDA) culture medium and virulence on the adult insect. Conidia in watery suspension with Tween 80 (0.05%), at various concentrations (0.62 x 106; 0.24 x 106 and 0.43 x 106 conidia/mL) constituted the inoculum for the viability and virulence tests. Determination was made of the rate of germination to reisolated and no-reisolated fungus, 18h after the inoculation. Growth of the colonies and conidiogenesis were estimated in the intervals of 3, 6, 9, 12 and 15 days. Suspension of the conidia in concentrations caused mortality of 96.7, 83.4 and 91.1% in LT50 of 5.4, 5.9 and 5.3 days, respectively. The relative pathogen potency (RPP) indicated that the fungus was more aggressive after reisolation. It was verified that B. bassiana (URM-3447), reisolated from eggs, larvae and adults of the A. grandis, presented high viability of germination, colonial growth and conidiogenesis in PDA medium and high degree of virulence on the adult insect, being able to be used as an insect control agent.

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The labeling of red blood cells (RBC) with technetium-99m (99mTc) depends on a reducing agent and stannous chloride (SnCl(2)) and is widely utilized. This labeling may also be altered by drugs, and SnCl(2) reduces the survival of Escherichia coli cultures. Cauliflower (Brassica oleracea L. var. botrytis) is used in folk medicine and we evaluated its influence on (i) the labeling of blood elements with 99mTc, and (ii) on the survival of an E. coli strain. Blood was withdrawn from rats that drank the extract of cauliflower (15 days). Blood was incubated with SnCl(2) and with 99mTc, as sodium pertechnetate, centrifuged and plasma (P) and RBC were isolated. Samples of P and RBC were also precipitated, centrifuged and soluble and insoluble fractions isolated. E. coli culture was treated with SnCl(2) in the presence of cauliflower. The extract of cauliflower did not alter the fixation of 99mTc on blood fractions; however, it abolished the lethal effect of SnCl(2) on the E. coli culture. We suggest that the substances present in the extract of cauliflower probably, would have redox property with different mechanisms of action. The oxidant action of the substances of the extract would not be strong enough to oxidise the stannous ions altering the 99mTc-labeling. However, the referred substances could oxidise these ions sufficiently to protect the E. coli culture against the lethal effect of the stannous ion.

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La fertilidad en el hombre es evaluada pór las características seminales.Experimentalmente el test de fertilidad se acepta como el máas confiable pero imposible de reproducir en humanos porque implica la capacidad de gestación.La técnica simplificada de microaspiración del esperma,resultó muy práctica pero había que verificar si los parámetros seminales así obtenidos tenían correlación con el test de apareamientoSe utilizaron 20 ratas y 20 ratas albinas del linaje Wistar,con edades durante el test de apareamiento de 70 días y peso medio de 260 g.Para el procedimiento de microaspiración del esperma del epidídimo,fueron utilizados las 40 ratas Wistar(20+20)con edad de 70 días y un peso medio de 200 g para el test de apareamiento.Para la microaspiración,las mismas ratas tenían 160 días,con un peso medio de 368,4 g.En el test de apareamiento se utilizó el método Poiley,se observaron el número de embarazos y de crías.Se utilizó la técnica de microaspiración de esperma de la cola del epidídimo para evaluar la motilida y concentración espermática.El test T de Student fue utilizado en la evaluación de los parámetros seminales.Se correlacionó el número de crías con la motilidad y la concentración espermática obteniéndose un nivel de significancia de 0,5(p<0,05)No hubo diferencias estadísticas en el número de embarazos,número de hijos,motilidad y concentración espermática

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La fertilidad en el hombre es evaluada pór las características seminales.Experimentalmente el test de fertilidad se acepta como el máas confiable pero imposible de reproducir en humanos porque implica la capacidad de gestación.La técnica simplificada de microaspiración del esperma,resultó muy práctica pero había que verificar si los parámetros seminales así obtenidos tenían correlación con el test de apareamientoSe utilizaron 20 ratas y 20 ratas albinas del linaje Wistar,con edades durante el test de apareamiento de 70 días y peso medio de 260 g.Para el procedimiento de microaspiración del esperma del epidídimo,fueron utilizados las 40 ratas Wistar(20+20)con edad de 70 días y un peso medio de 200 g para el test de apareamiento.Para la microaspiración,las mismas ratas tenían 160 días,con un peso medio de 368,4 g.En el test de apareamiento se utilizó el método Poiley,se observaron el número de embarazos y de crías.Se utilizó la técnica de microaspiración de esperma de la cola del epidídimo para evaluar la motilida y concentración espermática.El test T de Student fue utilizado en la evaluación de los parámetros seminales.Se correlacionó el número de crías con la motilidad y la concentración espermática obteniéndose un nivel de significancia de 0,5(p<0,05)No hubo diferencias estadísticas en el número de embarazos,número de hijos,motilidad y concentración espermática

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A wild strain of Metarhizium anisopliae, an entomopathogenic fungus, was submitted to three mutagenic agents: gamma radiation, ultraviolet light and nitrous acid. Survival curves were obtained and mutants were selected using different mutagenic doses which gave 1 to 5% survival. Morphological and auxotrophic mutants were isolated. Morphological mutants were grouped in a class with yellow conidia and other with pale vinaceous conidia as opposed to the green wild type conidia. Auxotrophic mutants had requirements for vitamin and aminoacid biosynthesis. More than 58% of the total auxotrophk mutants required proline/aipnine. Gamma radiation showed to be the most efficient mutagenic agent giving 0.2% of auxotrophk mutants followed by ultraviolet light (0.12%) and nitrous acid (0.06%).The conidial colour and auxotrophk mutants isolated until now from M. anisopliae were reviewed.

Uma linhagem selvagem do fungo entomopatogênico Metarhizium anisopliae foi submetida à ação de três agentes mutagênicos: radiação gama, luz ultravioleta e ácido nitroso. Curvas de sobrevivência foram obtidas para cada mutagênicos utilizado e mutantes foram selecionados a partir de doses dos mutagênicos que proporcionassem de 1 a 5% de sobrevivência. Mutantes morfológicos para a coloração de conídios e mutantes auxotróficos foram isolados. Mutantes para coloração de conidios foram agrupados em duas classes, uma com conídios amarelos e outra com conídios vinho pálido. Os mutantes auxotróficos obtidos foram deficientes para aminoácidos e vitaminas e mais de 58% deles eram auxotróficos para prolina/argmina. Radiação gama foi o mutagênico mais eficiente com uma porcentagem de obtenção de mulantes auxotróficos de aproximadamente 0,2%, seguido pela luz ultravioleta (0.12%) e pelo ácido nitroso (0.06%).Os mulantes morfológicos e auxotróficos obtidos até o momento em Metarhizium anisopliae foram revistos.

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A wild strain of Metarhizium anisopliae, an entomopathogenic fungus, was submitted to three mutagenic agents: gamma radiation, ultraviolet light and nitrous acid. Survival curves were obtained and mutants were selected using different mutagenic doses which gave 1 to 5% survival. Morphological and auxotrophic mutants were isolated. Morphological mutants were grouped in a class with yellow conidia and other with pale vinaceous conidia as opposed to the green wild type conidia. Auxotrophic mutants had requirements for vitamin and aminoacid biosynthesis. More than 58% of the total auxotrophk mutants required proline/aipnine. Gamma radiation showed to be the most efficient mutagenic agent giving 0.2% of auxotrophk mutants followed by ultraviolet light (0.12%) and nitrous acid (0.06%).The conidial colour and auxotrophk mutants isolated until now from M. anisopliae were reviewed.

Uma linhagem selvagem do fungo entomopatogênico Metarhizium anisopliae foi submetida à ação de três agentes mutagênicos: radiação gama, luz ultravioleta e ácido nitroso. Curvas de sobrevivência foram obtidas para cada mutagênicos utilizado e mutantes foram selecionados a partir de doses dos mutagênicos que proporcionassem de 1 a 5% de sobrevivência. Mutantes morfológicos para a coloração de conídios e mutantes auxotróficos foram isolados. Mutantes para coloração de conidios foram agrupados em duas classes, uma com conídios amarelos e outra com conídios vinho pálido. Os mutantes auxotróficos obtidos foram deficientes para aminoácidos e vitaminas e mais de 58% deles eram auxotróficos para prolina/argmina. Radiação gama foi o mutagênico mais eficiente com uma porcentagem de obtenção de mulantes auxotróficos de aproximadamente 0,2%, seguido pela luz ultravioleta (0.12%) e pelo ácido nitroso (0.06%).Os mulantes morfológicos e auxotróficos obtidos até o momento em Metarhizium anisopliae foram revistos.

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