50 research outputs found

    Formação de clamidósporos pela fase micelial do Paracoccidioides brasiliensis

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    To investigate the role of some adverse environmental conditions in chlamy-dospore formation by the mycelial form of P. brasiliensis, we cultured four P. brasiliensis isolates (18, Bt4, 1183, Pb9) at 25°C within solid agar medium either rich or poor in nutrients. Isolates 18 and 1183 were also cultured under anaerobiosis in a nitrogen atmosphere. Isolate 18 produced great number of terminal and intercalary chlamydospore after 7-10 days of culture in a medium poor in nutrients (2% agar with 0.1% dextrose and polypepton). The three other isolates also produced chlamydospores under the same conditions, but in lower numbers. Chlamydospore production by isolate 18 was abolished when the fungus was cultured in two agar media rich in nutrients (brain heart infusion and potato dextrose agar). Anaerobic incubation of isolate 18 under an atmosphere of N2 showed small mycelial outgrowth with numerous chlamydospores. At the electron microscopical level, the chlamydospores showed one or various nuclei and numerous mitochondria, indicating great potential for further development. Accordingly, chlamydospores produced multiple budding after only 24 h incubation at 35°C. The results demonstrate that under adverse environmental conditions P. brasiliensis mycelial form produces chlamydospores within a short period of time.O papel do conteúdo nutritivo do meio de cultura e de oxigênio na produção de clamidósporos pela fase micelial do Paracoccidioides brasiliensis foi investigado. Quatro cepas do fungo (18, Bt4, 1183, Pb9) foram cultivadas, a 25°C, em meio sólido rico e pobre em nutrientes. As cepas 18 e 1183 foram também cultivadas em anerobiose em atmosfera de nitrogênio. A cepa 18 produziu grande número de clamidósporos terminais e intercalares após 7-10 dias de cultura em meio sólido pobre em nutrientes (agar 2%, com dextrose e polipeptona 0,1%). As outras três cepas produziram número significativamente menor de esporos. A cepa 18 não produziu clamidósporos quando cultivada em dois meios ricos em nutrientes (infusão de cérebro e coração, e agar dextrose de batata). A incubação anaeróbica da cepa 18 em atmosfera de nitrogênio apresentou pequeno crescimento micelial com a presença de numerosos clamidósporos. À nivel ultraestrutural, os clamidósporos apresentaram um ou mais núcleos e numerosas mitocôndrias, indicativos de potencial para posterior desenvolvimento. Assim, os esporos produziram gemulação múltipla 1 dia após incubação a 35°C. Os resultados demonstraram que, sob condições ambientais adversas, a fase micelial do P. brasiliensis produz clamidósporos em curto período de tempo. É possível que o fungo encontre condições semelhantes no solo, produzindo os esporos, que poderiam desempenhar papel na propagação da paracoccidioidomicose

    Sorotipos, "mating type" e ploidia de amostras de C. neoformans isoladas de pacientes no Brasil

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    Serotype, mating type and ploidy of 84 strains of Cryptococcus neoformans isolated from 61 AIDS and 23 non-AIDS patients admitted in a tertiary teaching hospital in São Paulo, Brazil were examined. Among 61 strains isolated from AIDS patients, 60 strains were var. grubii (serotype A). Only one strain was var. gattii (serotype B). No var. neoformans (serotype D) was found. Among 23 strains isolated from non-AIDS patients, 15 were var. grubii (serotype A) and the remaining 8 were var. gattii, all of which were serotype B. Seventy-three of the 75 serotype A strains were the heterothallic alpha type (MATalpha) and the remaining 2 were untypable (asexual). Most of the MATalpha strains (69/73) were haploid and the remaining 4 strains were diploid. Similarly, both of the 2 asexual strains among the 75 serotype A strains were haploid. There were no alpha-mating type (MATalpha) strains among the 84 isolates. All of the 8 var. gattii strains were serotype B and haploid. Among a total of 84 strains tested, neither serotype AD nor serotype D were found. Neither triploid nor tetraploid were found. These results suggest that the serological, sexual and ploidy characteristics in C. neoformans strains isolated from AIDS patients in São Paulo were rather simple, whereas strains isolated from non-AIDS patients presented serotype A and B with predominance of serotype A.Foram estudados os sorotipos, "mating type" e ploidia de 84 amostras de C. neoformans isoladas de 61 pacientes com AIDS e 23 não-AIDS em São Paulo. Das amostras isoladas de pacientes com AIDS, 60 foram identificadas como var. grubii (sorotipo A) e 1 como var. gattii (sorotipo B). Não houve isolamento do sorotipo D. Entre as amostras isoladas, de pacientes não-AIDS, 15 foram de var. grubii (sorotipo A) e as 8 restantes de var. gattii, todos do sorotipo B. Setenta e três dos 75 sorotipos A foram identificadas como cepas heterotálicas do fenótipo alfa (MATalfa) e as 2 remanescentes não-tipáveis (assexuada), eram haplóides. A maioria das cepas MATalfa (69/73) era haplóide sendo 4 diplóide. Não houve o isolamento de fenótipo a (MATa) entre as 84 cepas analisadas. Todas as 11 amostras de var. gattii eram do sorotipo B e haplóides. Não foram observados os sorotipos AD e C, nem células triplóides ou tetraplóides entre as 84 amostras estudadas. Os resultados sugerem, que as características sorológicas, sexuais e de ploidia de C. neoformans, isoladas de pacientes com AIDS em São Paulo, são particularmente simples, a maioria do sorotipo A, enquanto que nos pacientes não-AIDS foram observados tanto os sorotipos A quanto o B

    Seasonal level of hemoagglutinin inhibitinlt and its 2-mercaptoethanol sensitive antibody in the sera of swine (Epidemiological Study on Japanese Encephalitis, 67)

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    Seasonal level of hemoagglutinin inhibiting and its 2 -mercaptoethanol sensitive antibody in the sera of swine were researched and the following results were obtained. 1. The positive rate of hemoagglutination inhibit reaction (HI reaction) on swine showed 100% at maximum in the middle of September. 1980. The positive rate of 2-ME sensitive antibody showed the titer of over 1 : 40 with all swine examined in the middle of August, 1980. 2. The positive rate of HI reaction of inhabitants at Mukaiyama in Kurashiki City was 76.0% (on 8th in July, 1980) indicating the rather big decrease being compared with annual value of 90.6%, in 1976. Date indicated that increase In JE virus in swine as source of infection thought to be a vector of JE, caused a genuine case of JE, in 1980, as described below. 3. Higher positive rate of HI reaction and 2-ME sensitive positive rate of swine were observed in 1980. 4. One patient who suffered from JE was found In Kurashiki City in 1980. 5. Henceforth and continuously, Japanese Encephalitis should be investigated, above all on its occurance order with the number or Ct or the positive rate of hemoagglutination inhibit reaction in inhahitants and swine, etc. considering that J.E. has a high lethality rate and often leaves the terrible J. E. residue to patients

    ダイチョウキンノニシュノリンゴサンコウソノソンザイオヨビソレラノセイシツ : トクニNADヨウキュウセイコウソニツイテ

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    京都大学0048新制・課程博士理学博士甲第911号理博第164号新制||理||104(附属図書館)2499UT51-45-F86京都大学大学院理学研究科化学専攻(主査)教授 香月 裕彦, 教授 波多野 博行, 教授 由良 隆学位規則第5条第1項該当Kyoto UniversityDA
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