A New Real-Time PCR for the Detection of Plasmodium ovale wallikeri

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.     

Pectolytic clostridia isolated from sugar beet pulp silages in Italy

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.     

Cytogenetic study of a cell line of human penile cancer

A cell line of penile cancer from a 60-year-old Ugandan black patient has been studied by the authors. Transmission and scanning electron microscopy showed a large number of blebs and microvilli at cell surface; desmosomes were evident at TEM. Cytogenetic investigation (R-, C-, Nor-banding) showed the frequent presence of some markers: del(1p),del(1q),iso(3q),der(4),del(8p),11q+, t rob(13;14), 14p+, t rob(21;21). The epidemiology, geographical distribution, and aetiological role of human papilloma virus type 16 and herpes simplex type 2 are discussed.     

Pathogenicity of some chrysosporium species isolated in France

In order to appreciate the pathogenicity of several geophilic Chrysosporium species (including Anixiopsis stercoraria, Chrysosporium keratinophilum, C. tropicum, C. pannorum, C. state of Arthroderma curreyi, C. state of A. multifidum, and C. state of A. tuberculatum), the authors have realized two series of experimental infestations. Inoculation of these fungi on the back of guinea pigs produced rare erythematous scaling lesions which spontaneously disappeared 3–5 weeks later. No real hair invasion was observed. In white mice, eight weeks after intraperitoneal inoculation, granulomas with necrotic center were observed in the peritoneal tissue with C. keratinophilum, C. tropicum, C. state of A. curreyi and C. state of A. tuberculatum. Conidia were often intact in necrotic centers and retrocultures were positive. With C. state of A. curreyi, spherical spores associated with rare budding cells were noted. The pathogenic role of these keratinophilic fungi is uncertain. However, their ability to remain viable for several weeks in skin and peritoneal tissue indicates that they could become pathogen in certain circumstances.This paper was presented at the X^th congress of the International Society for Human and Animal Mycology at Barcelona, Spain from June 27 to July 1, 1988.     

Immunophenotyping of acute myeloid leukaemia: relevance of analysing different lineage-associated markers

The immunophenotype of 135 previously untreated patients with FAB defined acute myeloid leukaemia (AML) was studied at diagnosis. The panel of reagents included monoclonal antibodies (MoAb) recognising myeloid-associated determinants (CD11, CD13, CD14, CD33 and others) as well as MoAb directed towards lymphoid antigens (CD7, CD10, CD19) and TdT. The results indicate that CD13 and/or CD33 are consistently expressed in AML and only rarely in ALL blasts (131/135 + ve cases, versus 4/130 in ALL). Lymphoid antigen expression was rarely detected when CD10 and CD19 were investigated in AML (0.9% and 2% + ve cases, respectively), whereas significant positivities were found for TdT and CD7 (20% and 10% respectively). Concerning FAB subtypes, two new MoAb (LAM3 and LAM7) proved very useful in the specific recognition of AML with monocytic features. The phenotype CD13+ and/or CD33+, CD9+, HLA-DR- was found to be almost exclusive for M3 AML. The response to induction chemotherapy was analysed in CD7+ and in TdT+ patients. In the latter group a statistically significant lower response rate was found with respect to TdT-ve-AML patients.     

Importance of some factors on the dimorphism of Candida albicans

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.     

Assessment of the mutagenicity of fractions from s-triazine-treated Zea mays

A water-soluble extract from maize plants exposed to 3 s-triazine herbicides (atrazine, simazine and cyanazine) has been shown to be mutagenic in strain TA100 of Salmonella. No mutagenic activity was observed in any control plant extracts using either water or a variety of organic solvents. Gel permeation studies of the extracts suggest that the mutagen(s) are small molecules (less than 1000 MW). HPLC fractionation suggests that the mutagens formed from each of the 3 herbicides are similar in polarity and water solubility, eluting in a 50/50 water:methanol fraction. Approximately 89% of 14C-labeled HPLC chromatographable metabolites of atrazine were also associated with this fraction, suggesting a close chemical link between a labeled but unidentified metabolite and the mutagenic activity.