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Samples of seeds collected from commercially available cotton seed lots in Turkey were assayed for Verticillium dahliae. V. dahliae was successfully isolated from 67 of 104 seed lots tested, a successful isolation rate of nearly 65 %. Vegetative compatibility of the isolates was assessed through complementation tests using nitrate non-utilizing mutants. Of the 188 isolates obtained, 105 were classified as VCG1A, 17 as VCG2A, 64 as VCG2B and two as VCG4B. All 50 of the isolates tested in the greenhouse on cotton cv. DP 15-21 and Acala SJ-1 were pathogenic on both cultivars. As a group, AUDPC values were significantly higher ( P < 0.05) for VCG1A than for VCG2 and VCG4B isolates. These data suggest that: (1) commercial cotton seed lots are commonly infected with V. dahliae and thus may serve as primary sources of the pathogen; (2) cotton isolates of V. dahliae belong to VCG1A, 2A, 2B and 4B and these strains are widely distributed via seed lots; and (3) VCG1 and VCG2 are distinct pathotypes of V. dahliae that vary in their virulence to cotton. [ABSTRACT FROM AUTHOR]

Amebiasis is a severe illness caused by Entamoebachistolytica. The aim of this study is to evaluate the in vitro amebicidal activity of the rhizomes and aerial parts of Allium sivasicum, an endemic plant species from the flora of Turkey. Both extracts showed a time- and dose-dependent amebicidal action on the trophozoites. Among the extracts tested, rhizomes of A. sivasicum showed the strongest amebicidal effect on the trophozoites. In the presence of the rhizome extract at 2.0 mg/ml concentration, all of the trophozoites available in media have completely been killed within the 72nd hour. At 4.0 mg/ml extract concentration, all of the trophozoites available in media have completely been killed by the rhizome extract from the time of 24th hour. At 32.0 mg/ml extract concentration, 73.7% of the trophozoites were successfully killed by the extract within the first experimental hour. Aerial part extract at 4.0 mg/ml concentration completely killed the trophozoited within the 48th hour of the experimental procedure. At 8.0 mg/ml extract concentration, all of the trophozoites available in media have completely been killed by the aerial part extract from the time of 24th hour. At 32.0 mg/ml extract concentration, 67.7% of the trophozoites were successfully killed by the extract within the first experimental hour. These results suggest that the plant species evaluated here is a potential therapeutic drug for the treatment of Entamoeba infections, but it still needs to be evaluated quantitatively for determining the active phytochemicals. [ABSTRACT FROM AUTHOR]

Amoebic keratitis is difficult to treat without total efficacy in some patients because of cysts, which are less susceptible than trophozoites to the usual treatments. The aim of this study is to evaluate the in vitro amoebicidal activity of the methanolic extracts of Satureja cuneifolia and Melissa officinalis. In the presence of methanolic extracts (ranging from 1.0 to 32.0 mg/ml), numbers of the viable Acanthamoe castellanii trophozoites and cysts were decreased during the experimental process. Both extracts showed a time- and dose-dependent amoebicidal action on the trophozoites and cysts. Among the extracts tested, S. cuneifolia showed the strongest amoebicidal effect on the trophozoites and cysts. In the presence of 32 mg/ml extract, no viable trophozoites were observed within 24 h. At the same concentration value, the extract was found effective against the cysts at a rate of 46.3% within 72 h of the experimental process. At 16 mg/ml extract concentration, no viable trophozoites were also observed in the 24th hour of the experiment. At the end of the experimental process, 34.7% of the cysts were killed by the extract. M. officinalis showed moderate amoebicidal effect. At the concentration of 32 mg/ml, 44.3% and 30.0% of the trophozoites and cysts were killed by the extract, respectively. Results obtained from these concentration values were found statistically different in terms of their actions both on trophozoites and cysts ( p < 0.05). [ABSTRACT FROM AUTHOR]

The ciliate Uronema nigricans was found to acquire tolerance to mercury after being fed mercury-laden bacteria followed by exposure of washed suspensions of these ciliates to various concentrations of mercury in solution. Significant differences in percent mortality were observed for ciliates fed mercury-laden bacteria compared with control suspensions fed mercury-free bacteria. The phenomenon of acquired mercury tolerance was demonstrated within a single generation time. Ciliates fed mercury-free bacteria and subsequently exposed to increasing levels of mercury in solution showed an elevated tolerance to concentrations which, on initial testing, resulted in mortality of 83% of the ciliate population. The effect of ingesting mercury-laden bacteria on growth rate of Uronema was examined, and results showed no significant differences in growth rates of both 3- and 14-day-old cultures of protozoa that had been fed mercury-laden and mercury-free bacteria under controlled conditions. [ABSTRACT FROM AUTHOR]

Copepods of the genus Eurytemora, isolated from the Patuxent River, a tributary of Chesapeake Bay, were fed suspensions of the ciliate Uronema isolated from the Rhode River, a subestuary of Chesapeake Bay. Grazing by copepods was determined by the decrease in numbers of ciliates, which were monitored by both direct counting and particle size analysis. Results from both methods of analysis showed significant reduction in the numbers of Uronema in the suspension when Eurytemora was present. Survival of copepods with ciliates added as food source was significantly longer than without ciliates. Analysis of field samples collected in the fall showed that ciliates comprised approximately 20% of the total plankton biomass at selected sampling sites. The results of the laboratory and field studies indicate that copepods can feed on ciliates and suggest that, in nature, ciliates may comprise an important source of food for copepods. [ABSTRACT FROM AUTHOR]

The organisms responsible for nosocomial pneumonia are continuously evolving. Gramnegative bacilli have become the most common etiologic agents over the past 20 years, and with this evolution has come a better understanding of the pathogenesis of gram-negative bacillary pneumonia. Some gram-positive cocci, such as enterococci, group B beta hemolytic streptococci and methicillin-resistant Staphylococcus aureus, haven taken on new significance in nosocomial respiratory infections. Streptococcus pneumoniae, nontypeable Haemophilus influenzae and Branhamella catarrhalis are increasingly reported in hospitalized patients with chronic lung disease. Etiologic agents will change as new antibiotics are introduced. A better understanding of etiologic agents and their pathogens may be the best tool toward preventing hospital-acquired pneumonia. [ABSTRACT FROM AUTHOR]

In vitro isometric contractile tension was measured in heart and skeletal muscle in 3 groups of mice: 1. a control group, 2. a group maintained for 27 weeks on 20% alcohol, and 3. a group whose fluid intake was restricted to the extent equaling that which occurred in the alcohol treated animals. Results showed a reduction in cardiac twitch tension in both the alcohol and fluid restricted group, as compared to normal controls. We therefore consider that dehydration per se may play an important role in the etiology of alcoholic cardiomyopathy. [ABSTRACT FROM AUTHOR]

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