Interactions of Fungi and Algae from the Greenland Ice Sheet.

Heavily pigmented glacier ice algae Ancylonema nordenskiöldii and Ancylonema alaskanum (Zygnematophyceae, Streptophyta) reduce the bare ice albedo of the Greenland Ice Sheet, amplifying melt from the largest cryospheric contributor to eustatic sea-level rise. Little information is available about glacier ice algae interactions with other microbial communities within the surface ice environment, including fungi, which may be important for sustaining algal bloom development. To address this substantial knowledge gap and investigate the nature of algal-fungal interactions, an ex situ co-cultivation experiment with two species of fungi, recently isolated from the surface of the Greenland Ice Sheet (here proposed new species Penicillium anthracinoglaciei Perini, Frisvad and Zalar, Mycobank (MB 835602), and Articulospora sp.), and the mixed microbial community dominated by glacier ice algae was performed. The utilization of the dark pigment purpurogallin carboxylic acid-6-O-ß-D-glucopyranoside (C18H18O12) by the two fungi was also evaluated in a separate experiment. P. anthracinoglaciei was capable of utilizing and converting the pigment to purpurogallin carboxylic acid, possibly using the sugar moiety as a nutrient source. Furthermore, after 3 weeks of incubation in the presence of P. anthracinoglaciei, a significantly slower decline in the maximum quantum efficiency (Fv/Fm, inverse proxy of algal stress) in glacier ice algae, compared to other treatments, was evident, suggesting a positive relationship between these species. Articulospora sp. did uptake the glycosylated purpurogallin, but did not seem to be involved in its conversion to aglycone derivative. At the end of the incubation experiments and, in conjunction with increased algal mortality, we detected a substantially increasing presence of the zoosporic fungi Chytridiomycota suggesting an important role for them as decomposers or parasites of glacier ice algae.

Importance of soil and vineyard management in the determination of grapevine mineral composition.

The spatial variability of the mineral composition of grapevines in production vineyards along the east Adriatic coast was determined and compared between conventional and sustainable vineyard management. Cluster analysis shows a high level of spatial variability even within the individual locations. Factor analysis reveals three factors with strong loading for the macronutrients K and P and the micronutrient Mn, which explain 67% of the total variance in the mineral composition. Here, 26% to 34% of the variance of these three elements can be explained by abiotic and biotic soil parameters, with soil concentrations of K, Fe and Cu, organic matter content, and vesicular colonisation showing the strongest effects on the mineral composition of the grapevines. In addition, analysis of the mineral composition data shows significant differences between differently managed vineyards, with increased bioaccumulation of P and K in sustainable vineyards, while Zn bioaccumulation was increased in conventional vineyards. Our data confirm the importance of soil and vineyard management in the concept of terroir, and demonstrate the effects of sustainable management practices on the mineral nutrition of grapevines that result from modified nutrient availability related to changes in the abiotic and biotic characteristics of the soil.

Application of temporal temperature gradient gel electrophoresis for characterisation of fungal endophyte communities of Salix caprea L. in a heavy metal polluted soil.

Fungal endophytes can affect the heavy metal uptake of their host plants and increase the tolerance of their host plants to heavy metal stress. Therefore, in the present study, a wide-range screening of the fungal endophyte communities was conducted to determine the fungal distribution and diversity on S. caprea roots on a metal polluted site. Fungal communities were screened using amplification with the 5.8S-ITS2-28S part of the rDNA operon, with the resulting amplicons analysed by temporal temperature gradient gel electrophoresis (TTGE) and sequencing. This technique is reproducible and shows good coverage of ascomycete and basidiomycete taxa, as 68% and 32% of all of the sequences, respectively. No clear shift in fungal ITS-TTGE profiles from S. caprea roots was seen along the secondary succession stages. Ascomycetes dominated the more polluted plots, while there was a greater diversity of basidiomycetes in the less polluted and control plots, suggesting greater tolerance of ascomycetes in comparison with basidiomycete fungi. The high diversity of DSEs was confirmed at the highly metal-enriched locations, with species belonging to the genera Phialophora, Phialocephala and Leptodontidium. Furthermore, the DSE colonisation of S. caprea roots and the frequency of the sequences showing affinity towards DSE genus Phialophora, showed good correspondence with soil Pb, Cd and plant-available P concentrations, possibly indicating that DSEs improve metal tolerance of willows to high heavy metal contamination.

Porcine mitogen-induced interferon.

Induction of porcine interferon (PoIFN) with different lectins (phytohaemagglutinin, Lens culinaris lectin, Arachis hypogea lectin) in various concentrations (500, 50 and 5 micrograms/ml) was studied. Kinetics of PoIFN appearance was analyzed by antiviral and antiproliferative tests in human transformed and nontransformed cells. The relation between antiviral and antiproliferative activity of PoIFN in terms of respective units was determined. PoIFN was characterized in comparison with human interferon alpha by the acidostability and thermostability tests.

Toxocara antibodies in patients with visceral or ocular disorder in Slovenia.

The incidence of Toxocara antibodies was determined in 319 sera from patients suspected of having Toxocara infection. Serological responses were compared with clinical manifestations and age of the patients. A seropositive reaction was found in 24% of the patients. Highly positive results (OD 0.510-1.000 and OD > 1.000) by ELISA were obtained significantly more frequently in younger patients than in older ones (p < 0.005). The percentage of seropositive patients with visceral disorder was found to decrease with age, whereas the proportion of seropositive patients with ocular disorder increased with age. Serologically confirmed Toxocara infection in Slovenia alerted us to the fact that this health issue should be given due attention in the future.

The 3'-keto-diol equilibrium of trospectomycin sulfate bulk drug and freeze-dried formulation: solid-state carbon-13 cross-polarization magic angle spinning (CP/MAS) and high-resolution carbon-13 nuclear magnetic resonance (NMR) spectroscopy studies.

Understanding how moisture interacts with a drug or formulation is a critical component of product development. This study demonstrates how water affects the 3'-gem-diol<==>3'-keto equilibrium in trospectomycin sulfate bulk drug and freeze-dried formulation, as probed by solid-state carbon-13 cross-polarization magic angle spinning (CP/MAS) and high-resolution nuclear magnetic resonance (NMR) spectroscopy. Drying the bulk drug or formulation to low water levels dehydrates trospectomycin sulfate from the diol to the keto form. Carbon-13 CP/MAS NMR spectroscopy measures the keto drug concentration in solid samples directly. The bulk drug, which contains approximately 16% water, is more than 90% in the 3'-diol form. Oven drying to < 3% water converts approximately 75% of the drug to the 3'-keto form. The drug is formulated as a freeze-dried, sterile powder that can contain up to 12% water depending on the freeze-drying conditions. These studies show that the 3'-keto concentration rises uniformly (up to 75%) with decreasing residual water in the freeze-dried cake. The keto-diol equilibrium was also studied in solution by high-resolution carbon-13 NMR experiments, and it was found that raising the temperature or using dimethyl sulfoxide (DMSO) as a solvent also dehydrates the drug. For example, in aqueous solution at 25 degrees C, nearly all (> 95%) of the drug is in the 3'-diol form. After equilibration at 60 degrees C, however, the 3'-keto content increases to 7%, and in d6-DMSO solvent at 25 degrees C the drug is mostly (60%) in the 3'-keto form.

Incidence of congenital toxoplasmosis in the Republic of Slovenia.

Over a 12-month period, 3959 pregnant women were systematically tested with the Sabin-Feldman dye test in order to assess the incidence of congenital toxoplasmosis in Slovenia. The results suggest that this is approximately 3/1000 live births. This relatively high incidence of congenital toxoplasmosis in Slovenia may make the costing of preventive screening programmes justifiable.

Interactions between human and porcine interferons.

To investigate the possible interactions between human and porcine interferons (IFNs) in vitro, human transformed (FL) and nontransformed (HEF) cells were treated with either HuIFN alpha and/or gamma and porcine alpha and/or gamma. In both cases the antiproliferative activity was measured to determine the effects of different combinations between human and porcine IFNs on cell proliferation. Combinations of human and porcine IFNs acted mostly antagonistically with exception of IFN combination Hu-alpha/Po-gamma which showed a synergic cooperativity in therms of antiproliferative activity on human transformed cells.

Epidemiological model of hepatitis B with age structure.

Multistate epidemiological model with age structure is constructed on the grounds of natural history of the hepatitis B. Essential epidemiological classes constitute the basis of the model. Epidemiological parameters and the coefficients of transfer among the classes were determined from available information. Uncertainty of infectiousness of some classes of the population was an important constraint in model formulation. Population structure, the distribution of epidemiological classes and other parametric values were rather arbitrarily set but these can be changed as more accurate information becomes available. As new information on natural history may become available this can be incorporated into the present model, with appropriate modifications of its structure. The computer program+ of the model has been written in BASIC language, and can be accommodated within microcomputers. The model is used for simulation of endemic and epidemic situations. It is applied for simulating the natural course of infection as well as the effects of various public health interventions, such as passive and active immunization and/or application of appropriate sanitary and hygienic measures. The cost-effectiveness analysis of various public health control programmes can also be carried out with the model. The model is evaluated through the simulations of actual and hypothetical situations. The model in its present form, permits simulation of the disease dynamics in various populations and epidemic situations. It seems to be a useful tool in the study of hepatitis B dynamics, its epidemic patterns and in the search for the effective and cost-effective, control strategies.

Evaluation of EIA kits for the detection of HIV antibodies.

We compared four commercially available enzyme immunoassay (EIA) kits for the detection of HIV antibodies using immunoblot analysis as a confirmatory test. The kits gave satisfactory results as far as sensitivity and specificity are concerned as required for the use in the laboratories of blood banks. For the sera of patients on haemodialysis, haemophiliacs, patients "under observation" for AIDS and homosexuals the results obtained by Behring and Organon kits were less satisfactory, as the number of false positive results was much higher than with kits produced by Genetic and Wellcome. The frequency of false negative results was small in the tests using Organon and Genetic kits, while using Behring and Wellcome kits no false negative results were found.

Effect of rat (beta)-interferon on intracellular levels of hydrolases in rat embryonal fibroblasts (Wistar strain).

The effect of rat beta-interferon (IFN) on the intracellular level of thiole and acid proteases and alkaline phosphatases was investigated. When nontransformed rat embryonal fibroblasts (REF) (Wistar strain) were treated with homologous IFN, a time independent decrease of hydrolase enzyme levels was observed. IFN treatment of transformed cells lead to a time dependent decrease of thiole proteases within 90 min. The values for acid proteases remained unchanged after the short term IFN treatment.

The effect of intracellular proteinases on transformation of human lymphocytes.

The effect of two intracellular proteinases, calf liver chymotrypsin-like neutral proteinase and human brain cathepsin H, and of two proteinase inhibitors, leupeptin and endogenous cysteine proteinases inhibitor, was studied on unstimulated and mitogen-stimulated peripheral human blood lymphocytes. Classification of blood samples into four types, on the basis of their potential for spontaneous and mitogen-stimulated transformation, helped in analyzing the results. Within some of these types, at least, there appears certain uniformity of response to proteinase action. Lymphocytes most susceptible to proteinase action were those that were insensitive to phytohemagglutinin mitogenic stimulus. The maximal effect of proteinases or their inhibitors was obtained most often when these agents were added to lymphocyte cultures 24 hours before mitogen. Both proteinases, although of quite different specificities, gave very often results of similar trend on the same lymphocyte culture. Moreover, this was followed also by the two inhibitors, which showed not only inhibitory, but also potentiating power of action on lymphocyte transformation. The regulatory nature of the action of proteinases within lymphocytes and other cells is underlined.

Epidemiological model of hepatitis B.

This is a preliminary report on a multistate epidemiological model without age structure constructed on the grounds of the natural history of hepatitis B. In determining twelve essential epidemiological classes and related epidemiological parameters the lack of precise definitions of certain classes and their infectiousness was an important constraint in model formulation. For this reason the distribution of some classes and their parametric values were rather arbitrarily set. As more exact information on natural history becomes available it can be directly incorporated into the present model. The computer programme of the model has been written in basic language. The model was used for the simulation of endemic and epidemic situations. It was applied for simulating the natural course of infection as well as the effects of various public health interventions, such as passive and active immunization and/or application of appropriate sanitary and hygienic measures. The model is evaluated through the above simulations of actual and hypothetical situations. The cost-effectiveness analysis of various public health interventions can also be carried out with the model. The model in its present form, in spite of some uncertainties as far as epidemiological parameters are concerned, seems to be useful in the study of hepatitis B dynamics and its epidemiological patterns and in the search for effective and cost-effective control strategies. The model needs further refinement.

Effect of homologous and heterologous interferons on proteolytic activity of normal and transformed cells.

The authors investigated the effect of various types of interferons (INF) on the activity of intracellular neutral and cysteine proteinases (cathepsin B and H) in normal and transformed rat embryonic fibroblasts. A substantially stronger inhibitory effect was observed with all three types of IFN on the proteolytic enzymes in transformed cells if compared to that on normal cells. Heterologous IFN reduces the activity of cysteine proteinases by 33% and neutral proteinases by 79%. Homologous IFN strongly reduced the activity of cysteine proteinases in transformed cells (59%) used in the experiments, but the inhibition of neutral proteinases remained nearly unchanged if compared with normal cells (18%).

Animal corneas as tools for the testing of antiviral compounds.

As a number of viruses can be titrated on corneas of various animals, the corneal method was used to detect antiviral activity of some derivatives of thiazolidine and related compounds with a low toxicity. In herpetic infections of rabbit cornea, 2-(1-isopropylidene)azino-3-(beta-D-ribofuranosyl)-methoxycarbonylmethylenethiazolidine-4-one showed for a mean of 2.1 greater activity than IDU. In piglet corneas, lesions produced by adenovirus type 8 were inhibited by a mean of 3.4 log CID50 by 5-(2,3,5-tribenzoyl-beta-D-ribofuranosyl)-(2H)-tetrazol and by a mean value of 3 log CID50 by 4-(2,3,5-tri-o-benzoyl-beta-D-ribofuranosyl) thiosemicarbazide. The multiple microinoculation technique of calculating corneal infectivity allows many of the advantages of sensitivity and statistical validity usually associated only with cell culture methods to be obtained from an in vivo system. Furthermore it allows observations concerning toxicity of the drug tested on the eye. We believe that this method should form a part of the "biography" of any compound seriously considered for the ocular treatment of virus diseases. This test goes a long way in bridging the gap between in vitro tests and trials in humans.

Similarities of cellular receptors for interferon and cortisol.

Cellular receptors are molecules located on the cell membrane. Their function is to bind different molecules to the cell surface. These molecules can penetrate into the cytoplasm and trigger cellular changes. One kind of such bound molecules are interferons and corticosteroids. Until very recently very little was known about interferon's receptors on the cell surface, mechanisms of interferon's binding to them or about kinetics of such binding. On the basis of results published elsewhere and on the basis of experimental results, the authors suggest: 1) receptors for interferon and cortisol are glycoproteins located on the cell surface, 2) in analogy with PHA receptors they are chemically sialoglycoproteins, 3) binding kinetics of cortisol and interferon is similar, 4) interferon and cortisol compete for cellular receptors, 5) binding of cortisol or interferon is dependent on allosteric configuration of receptor molecules.

An outbreak of acute hemorrhagic conjunctivitis in Yugoslavia in 1973.

An outbreak of approximately 200 cases of acute hemorrhagic conjunctivitis is described in Prekmurje, a northern province in Yugoslavia. The epidemic was caused by enterovirus type 70, serologically identical with the causative agents of similar outbreaks in London and Japan. The origin of the outbreak could not be elucidated but a link was seen between this case and a small outbreak in Veenendaal in the Netherlands.