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1.
Adriana Calderaro Giovanna Piccolo Chiara Gorrini Sara Montecchini Sabina Rossi Maria Cristina Medici Carlo Chezzi Georges Snounou 《PloS one》2012,7(10)
It has been proposed that ovale malaria in humans is caused by two closely related but distinct species of malaria parasites: P. ovale curtisi and P. ovale wallikeri. We have extended and optimized a Real-time PCR assay targeting the parasite’s small subunit ribosomal RNA (ssrRNA) gene to detect both these species. When the assay was applied to 31 archival blood samples from patients diagnosed with P. ovale, it was found that the infection in 20 was due to P. ovale curtisi and in the remaining 11 to P. ovale wallikeri. Thus, this assay provides a useful tool that can be applied to epidemiological investigations of the two newly recognized distinct P. ovale species, that might reveal if these species also differ in their clinical manifestation, drugs susceptibility and relapse periodicity. The results presented confirm that P. ovale wallikeri is not confined to Southeast Asia, since the majority of the patients analyzed in this study had acquired their P. ovale infection in African countries, mostly situated in West Africa. 相似文献
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Twenty-eight strains of pectolytic clostridia were isolated from sugar beet pulp silages. Seventeen non-pigmented strains were presumed to be Clostridium acetobutylicum ; the remaining 11 pigmented strains were similar to Cl. felsineum. The addition of molasses to sugar beet pulps favoured the growth of other bacteria, particularly lactic acid organisms, whereas pectolytic clostridia were only occasionally found. The pectolytic clostridia promoted the structure loss of simulated silages. The use of molasses in sugar beet pulp ensiling was suggested to prevent texture loss of the ensiled mass. 相似文献
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Valerio Vidotto Giuseppe Picerno Stefano Caramello Giovanna Paniate 《Mycopathologia》1988,104(3):129-135
The passage between the yeast and mycelial forms of Candida albicans B 311-10 was studied by using the minimal syntehtic medium of Shepherd et al. [19] modified without biotin and with low glucose concentrations. It was observed that biotin, aminoacids and particularly pH are not important factors in the dimorphism of C. albicans. The only factor of notable importance in the passage of yeast form to mycelial form in C. albicans was glucose concentration. 相似文献
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Edda De Rossi Giovanna Riccardi Anna Maria Sanangelantoni Orio Ciferri 《FEMS microbiology letters》1985,30(1-2):239-244
Abstract A Spirulina platensis gene library has been constructed using cosmid vector pMMB34. The cosmid bank was controlled for its random gene distribution by colony hybridization. Genes were identified using either homologous or heterologous probes of genes involved in photosynthesis (large and small subunit of d -ribulose 1,5-bisphosphate carboxylase, 32 kDa thylakoid protein, α, β subunits of C-phycocyanin) and protein synthesis (elongation factors EF-Tu, EF-G). 相似文献
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Giovanna P. Marziani Longo Marcella Bracale Gianfranca Rossi Claudio P. Longo 《Plant molecular biology》1990,14(4):569-573
Cotyledons were excised from imbibed watermelon seeds, grown for 4 days in darkness on water or 10 M benzyladenine (BA) and then tested for the presence of the light-harvesting chlorophyll a/b protein (LHCP) and its mRNA. LHCP was assayed immunologically by western blotting of SDS gels: the protein was present in plastids, but it was not recovered with the thylakoid fraction. Antibodies directed against LHCP precipitated a 32 kDa polypeptide from translation products of poly(A) RNA of cotyledons only if these had been grown on BA. Taken together the data suggest that in absence of light cytokinins are necessary for the maintenance of a detectable level of LHCP-mRNA as well as for synthesis of the protein. 相似文献
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Giuliano Callaini Maria Giovanna Riparbelli Marcella Cintorino Sergio Antonio Tripodi Giorgio Bianciardi Piero Tosi Romano Dallai 《Biology of the cell / under the auspices of the European Cell Biology Organization》1994,81(1):39-45
Summary— Immunofluorescence and immunoelectron microscopy indicated that the antibody raised against the nuclear antigen Ki-67 of mammalian cells recognized antigenic determinants of early Drosophila embryos, localized on the outside of the nuclear envelope. Hence, the nuclear envelope of Drosophila appears to share a similar epitope with the chromosome scaffold of mitotic mammalian cells. With the progression of mitosis the antigen persisted around the mitotic spindle region and was also found in the pole regions at metaphase and anaphase. The antibody also stained the equatorial regions of the spindles from anaphase to late telophase. The antibody may therefore be used as a biochemical marker of the nuclear envelope for studying nuclear membrane biogenesis and behavior during the mitotic divisions of the Drosophila embryo. 相似文献