Seroprevalence study of tick borne encephalitis in Turin province.

BACKGROUND: Tick borne encephalitis (TBE) virus is diffused in some European countries and it is transmitted by tick bites. In Italy Isodex ricinus represents the main vector of the infection, that rarely produces the neurologic manifestations, characterising the secondary phase of the same. METHODS: In Italy TBE has been little studied and this only in the Middle and Northern regions of the country. Seroepidemiological researches were done prevalently on subjects at high risk of tick bite, such as hunters or forest guards and especially in Trentino and Tuscany. No precise information about TBE virus diffusion was disposable in the Piedmont region and particularly in the Susa valley where, before our investigation failed the data about it. RESULTS: We found that usual hunters and wild boar breeders seem to be particularly exposed to the risk of TBE virus infection, but none neurologic involvement was detected in the anamnesis of the significantly seropositive subjects and also of the borderline ones, that we have studied, despite the limited number of these subjects. CONCLUSIONS: Nevertheless we hope for a following extension of our case report, also in consideration that rare cases of encephalitis of unknown etiology, are signalled in Piedmont.

Effects of Aspergillus terreus extract on herpes simplex 1 virus replication.

In this study we reported about the antiviral activity of Aspergillus terreus alcohol extract against Herpes simplex type 1 virus. This activity is dose-dependent, is related to the concentration of the challenging virus and depends particularly on a proteic fraction of 5-10 Kda. Optimal effects were observed with doses ranging from 25 to 6.25 micrograms/ml for crude alcohol extract and up to 3 micrograms/ml for 5-10 Kda fraction. Moreover, antiviral activity was evident in viral replication, but not on virus out of the cells. An increased 3H thymidine incorporation was noted on infected cells treated with the extract and this effect may suggest an intracellular accumulation of viral DNA in the absence or reduction of virion production.

Effect of Aspergillus terreus extract on neoplastic and non-neoplastic cell replication.

There are very few and unconfirmed data regarding the antineoplastic activity of mycotic derivates in human cells. The effects on neoplastic and non-neoplastic cell replication of Aspergillus terreus extracts have been tested. In fact, among different species of Aspergillus mycotoxin producers. A terreus seems to be more suitable for hypothetical therapeutic purposes because of its low mycotoxin toxicity. Very evident antiblastic activity of alcoholic crude extract of A. terreus on tumor cells has been demonstrated. Doses between 3.1 and 6.2 inhibited more than 50% of tumor cells; the same effect was obtained with doses > 25 micrograms/ml on non-neoplastic cells. The action of the crude extract does not influence cellular cAMP in either neoplastic or non-neoplastic cells. The antiblastic action seems to depend primarily on the inhibitory effect of DNA duplication. Some chromatographed fractions of the mycotic extract showed inhibiting or enhancing effects on cell growth.

In vitro inhibitory activity of citreoviridin against HIV-1 and an HIV-associated opportunist: Candida albicans.

Citreoviridin, a mycotoxin produced by some molds of the genera Penicillium and Aspergillus, inhibits the growth of bacteria of the Bacillus genus. Since significant information was not available on the effects of citreoviridin on eukaryotic cells and viruses, this molecule was tested on CD4+ T-lymphoid cell lines, on HIV-1 and on Candida albicans, which sometimes complicates HIV-infection. Antiviral activity was detected in H9 HTLV IIIB cells, a clone chronically infected by HIV-1. Citreoviridin reduced p24 in the supernatant of H9 HTLV IIIB in a dose-dependent manner with a pharmacological selectivity index of 2.6. In C. albicans, the effects of the mold-derivative were evaluated on some parameters associated with pathogenicity and virulence: cellular proliferation, germ tube production, expression of heat shock mannoproteins, release of proteases and phospholipases. At a 12.5 microM dose, citreoviridin showed a marked inhibitory effect on all parameters analyzed. As regards the mechanism of action, it is possible to hypothesize that the effects of citreoviridin may be due to a reduction of protein synthesis, since it inhibited the replication of HIV-1 at post-integrational stages and reduced the intracellular RNA and protein content in C. albicans.

Enzymatic profile of Cryptococcus neoformans strains by using the API-ZYM system.

Determination of the enzymatic profile of 41 Cryptococcus neoformans strains, 20 isolated from AIDS patients and 21 from bird droppings, was performed by using the API-ZYM commercial kit system (Bio-Mérieux, France), which tests 19 different kinds of enzymes. All the strains showed positive enzymatic activity to the esterase (C4) (n. 3). On the contrary, alkaline phosphatase (n. 2), cystine arylamidase (n. 8), trypsin (n. 9), chymotripsin (n. 10), alpha-galactosidase (n. 13), beta-glucuronidase (n. 15), alpha-mannosidase (n. 19), alpha-fucosidase (n. 20) were negative in all the strains. The other 10 enzymes (n. 4,5,6,7,11,12,14,16,17,18) were distributed among the strains in different positive percentages. From the results of each enzymatic profile obtained, the 20 AIDS strains were grouped into 15 types, while the 21 bird dropping strains were grouped into 14 types. Interestingly, only one enzyme profile type occurred in the strains isolated from the AIDS patients and from the bird droppings. These results suggest that the API ZYM system is useful in discriminating between the AIDS strains and the bird dropping strains.

Resistogram typing of oral Candida albicans isolates from normal subjects in three successive trials.

Sixty-six oral strains of Candida albicans, which had been consecutively isolated from 22 normal, young females in three isolation trials at intervals of one to three weeks, were biotyped by their susceptibility to boric acid, cetrimide, silver nitrate, sodium periodate and sodium selenite. The 66 isolates were grouped into 13 resistogram types. An identical biotype strain was found three times and twice in seven and six each of the 22 subjects in the three isolation trials, respectively. In the remaining nine subjects, different strains were found at the three trials. These results suggested that certain strains tended to persist in the oral cavity of the normal subjects although changes in the biotype of oral C. albicans strains occurred to a certain extent.

Correlation between germ tube production, phospholipase activity and serotype distribution in Candida albicans.

One-hundred and thirteen Candida albicans strains isolated from patients infected by the human immunodeficiency virus (HIV) and twenty five from HIV-negative individuals were studied. The C. albicans strains isolated from different sites of the body were tested for germ-tube (GT), phospholipase production and serotype. The results obtained indicate that the serotype A was predominant in all the groups except for the vaginal strains. No correlation was observed between phospholipase activity and serotype distribution. Germ tube (GT) production was higher among the serotype B strains. A positive correlation between GT induction and phospholipase activity was observed only for the isolates from the oral cavity. It is possible that the correlation between phospholipase activity and high GT production in C. albicans strains can facilitate the penetration through the mucosa.

Extracellular activity in Cryptococcus neoformans strains isolated from AIDS patients and from environmental sources.

Nineteen Cryptococcus neoformans strains isolated from AIDS patients and 16 from bird droppings were tested for their extracellular activity. Typical enzymatic activity that was different from other medically important yeasts was found. The results obtained may indicate that there are new extracellular enzymatic activities that imply a relationship between C. neoformans and its virulence. A correlation among the different enzymatic activities was also investigated and according to the results obtained no relationship was observed among any of the recorded extracellular enzymatic activities. Research on C. neoformans extracellular enzymatic activity is useful not only to better understand its metabolism but in particular to establish a possible relationship between its virulence and pathogenicity.

[Study on the presence of yeasts in the feces of the rock pigeon (Columba livia Gmelin 1789) from rural areas]. / Indagine sulla presenza di lieviti nelle feci di colombo torraiuolo (Columba livia Gmelin 1789) provenienti da contesti rurali.

The diffusion of rock-pigeon (domestic form of Columba livia Gmelin 1789) is greatly increasing owing to its high reproductivity; for this reason it is present in both countries and cities. This bird is considered an important vector of pathogens to man and domestic animals, and today it represents a serious hygienic-sanitary problem. Therefore we checked for the presence of yeasts in feces of rock-pigeons nesting in the Regional Park "La Mandria" (near Turin), visited mostly by school-children and retired. The yeasts isolated were: Candida albicans, C. krusei, C. guillermondii, C. intermedia, C. lusitaniae, C. parapsilosis, C. pseudotropicalis, C. rugosa, C. tropicalis, Cryptococcus albidus, C. laurentii, C. neoformans, C. terreus, Pichia membranaefaciens, Rhodotorula rubra, Saccharomyces cerevisiae, S. oleaginosus, S. telluris, Torulopsis candida, Trichosporon cutaneum. The incidence of the species isolated is reported on Tables 1 and 2.

[Presence of pathogenic yeasts in the feces of the semi-domesticated pigeon (Columba livia, Gmelin 1789, urban type) from the city of Turin]. / Sulla presenza di lieviti patogeni nelle feci di colombo torraiuolo (Columba livia, Gmelin 1789, forma urbana) della città di Torino.

The results of a survey on the presence of pathogenic yeasts in pigeon droppings collected in Turin, are shown. The study was carried out in 8 densely populated areas, where human-animal contact is highest. A total of 427 pigeon dropping samples, most of which fresh, were collected. 550 yeast colonies, clinically interesting or at least pathologically significant, were isolated by the identification routine methods. The yeasts belong to the following species: Candida albicans, C. humicola, C. krusei, C. guillermondii, C. lypolitica, C. lambica, C. parapsilosis, C. tropicalis, C. rugosa, C. zeylanoides, Cryptococcus albidus, C. laurentii, C. neoformans, Hansenula anomala, Geotrichum sp., Kloekera apiculata, Rhodotorula glutinis, R. rubra, Saccharomyces cerevisiae, Torulopsis candida, T. glabrata, Trichosporon beigelii, T. capitatum, T. cutaneum, T. pullulans.

Observation on the nucleic acids in the chlamydospores of Candida albicans.

The presence of red (RNA) and green (DNA) fluorescent material identifying nucleic acids in the chlamydospores of Candida albicans has been well documented. Red fluorescence in chlamydospores is relatively diffused and ranges from small spots, observed in hyphal cells, to the entire protoplasmic content. Green fluorescence is rarely visible in these structures and, when present it can be observed next to the plasmalemma. The initial percentage values of the two curves related to the cell counts of red fluorescence of the suspensor cells and chlamydospores showed remarkable differences between the two structures. About 54% of the chlamydospores showed red fluorescence compared to about 28% of the suspensor cells. It seems from the results obtained in this study that much RNA was produced and/or accumulated in the chlamydospores and suspensor cells, rather than in mycelium where red fluorescence was not observed. The results obtained sustain the hypothesis that a chlamydospore should he considered a fully functional cell that is morphologically and physiologically active and independent from mycelium.

Serotype identification of Cryptococcus neoformans by multiplex PCR.

The pathogenic yeast Cryptococcus neoformans is traditionally classified into three varieties with five serotypes: var. grubii (serotype A), var. neoformans (serotype D), var. gattii (serotypes B and C) and serotype AD (hybrid of serotypes A and D). A commercial kit, Crypto Check (Iatron Laboratories, Tokyo, Japan), has been used worldwide for serotyping isolated strains. However, its production was discontinued in 2004, and hence the present study aimed to develop a simple polymerase chain reaction (PCR) method for serotyping C. neoformans strains. Subjecting genomic DNA of 59 strains of the five serotypes to multiplex PCR amplification using a set of four primers designed for the laccase gene (LAC1) differentiated serotypes A, D, B and C, but could not separate serotype AD from serotype D. However, a primer pair designed for the capsule gene (CAP64) allowed serotypes D and AD to be differentiated. When PCR amplification was performed in the simultaneous presence of the above six primers, the five serotypes produced two to five DNA fragments that could be used to distinguish them. This multiplex PCR method is useful for serotyping C. neoformans isolates, and represents an effective replacement for the Crypto Check kit.

A review of HIV-1 Tat protein biological effects.

The authors have reviewed some biological properties of HIV-1 Tat protein, and have also reported some personal data. This viral regulatory protein is endowed with multifunctional activities, acting as an endogenous factor in the infected cells and exogenously, on those uninfected. In particular, Tat-induced proliferation and differentiation of HIV target cells which promotes viral infection, is discussed in this review. However, exogenous Tat protein can sometimes also produce, directly or indirectly, damaging effects in different organs and host systems, such as myocardium, kidney, liver and central nervous system (CNS). For example some data also demonstrate an increase in the apoptotic index induced by Tat at various levels, including the immune system. The effective role of HIV-1 Tat protein in promoting viral replication and its high immunogenicity suggest useful employment of this protein for therapeutic or preventive vaccine preparations.

[Influence of the substrate on culture and morphological characteristics of dermatophytes. Initial results relating to strains isolated from 586 patients]. / Influenza del substrato sui caratteri colturali e morfologici dei dermatofiti. Primi risultati relativi ai ceppi isolati da 586 pazienti.

During an epidemiological study on Dermatophytosis in the Metropolitan area of Turin were isolated: Microsporum canis, Trichophyton rubrum, Epidermophyton floccosum and Trichophyton mentagrophytes. The isolation of the species, was in the mean time, carried out on three different media: agar Sabouraud, Potato dextrose agar and Mycosel agar. In this work were observed the morphological differentiations of the species isolated, besides was compared the fertility of the media at different time of incubation.

Sources of fungal contamination in a burn-care unit.

A microbiological study was carried out in the burn-care unit of the Centro Traumatologico Ortopedico of Turin (Italy) in order to detect the most important sources of fungal contamination in patients at high risk of infection. Identification of the fungi was carried out only for those of medical mycological interest, with the exclusion of the yeast isolates.

A new minimal synthetic medium for germ-tube production in Candida albicans.

A new minimal synthetic medium, with low amount of glucose, without aminoacids, vitamins and neutral pH, which induces germ-tubes production in Candida albicans, is reported in this work. The results indicate a perfect agreement between the germ-tube test performed with the standard method in human or animal serum and this test performed in minimal synthetic medium. In this medium the germ-tube test for the presumptive identification of Candida albicans can be performed with the same formality, time and reproducibility as those in human or animal serum. This constitutes an interesting finding because it is easy to prepare, to store and is highly reproducible.

Paracoccidioidomycosis in Quillabamba, Peru, and its surroundings.

Three cases of paracoccidioidomycosis observed in 1990-1991 in Quillabamba, Peru, and its surroundings are described. The climate and the living conditions of the inhabitants favour paracoccidioidomycosis. It can be assumed that a majority of cases could not be identified, because the symptoms are disguised as other tropical diseases. The application of ketoconazole to the patients showed different results, from optimal to scarce, while temporary remission of the disease was obtained with itraconazole. The best therapy for paracoccidioidomycosis appears to be the application of amphotericin B plus sulphamidics.

A vitamin-free minimal synthetic medium for Cryptococcus neoformans.

The use of a simple synthetic medium is essential for study on the growth and physiology of Cryptococcus neoformans. In the present study, a minimal synthetic liquid medium (MSM) was tested for the growth of 23 C. neoformans strains. This medium contained a low concentration of glucose, ammonium sulphate and inorganic salts with a pH value of 4.5, but no amino acids or vitamins. The strains were starved for 4 days to eliminate nutrients which might have been carried over from their pre-culture medium. Then, they were inoculated in the MSM as an initial OD of 0.020 at 550 nm and incubated at 37 degrees C for 20 days. Cell growth was generally monitored daily by measuring the absorbance at 550 nm. The medium supported the growth of the strains tested and gave an average final OD of 0.500. The results obtained indicate that C. neoformans may be autotrophic with respect to vitamins and in particular to thiamine. The MSM medium is easy to prepare and store. It is highly reproducible and useful for studies on the growth and physiology of C. neoformans.

Effects of Aspergillus sulphureus mycotoxins on Cryptococcus neoformans.

Many studies have evaluated the toxicity of mycotoxins to mammals, but there is little information on their action against fungal cells, even although mycotoxins are frequently active against fungi in nature. A crude extract of Aspergillus sulphureus was tested for its growth-inhibitory effect on Cryptococcus neoformans. The reduction in cell growth of Cr. neoformans caused by the extract was dose dependent. Using a liquid medium containing 2% A. sulphureus extract, the RNA content of Cryptococcus amounted to about 60% of that of non-treated cells. Capsule thickening, demonstrated biochemically and with cytological stains, occurred at doses that had minimal effect on cell growth and RNA content. Our results suggest that the virulence of Cr. neoformans may increase in cases of coenobiosis with A. sulphureus, which is theoretically possible in places where corn-fed pigeons are numerous.