Acta Microbiologica Bulgarica

157-166

Authors: Tsaneva-Damyanova, D., Ivanova, L., Ivanova, I., Chervenkov, T., Todorova, T., Stoykova, Zh., Kostadinova, Ts.

The aim of thisinvestigation was to evaluate the various virological responses at several time points of therapy in chronically infected patients with dual HBV and HDV infection.A total of 23 patients, 8 (34.8%) women and 15 (65.2%) men with serologically proved chronic HBV and HDV infection, at the Gastroenterology Department of the University Hospital St. Marina, Varna, Bulgaria, were investigated in the hospital’s laboratories of Clinical Virology and Clinical Immunology. Quantitative determination of HBV DNA and HDV RNA was performed by Real-time PCR, on several occasions during and after therapy from 2012 to 2017.HBV viremia ranged from 1.0x10 2to 1.6x106cps/ml. HDV viremia ranged from 2.5x102 to 9.6x106cps/ml. HDV replication dominated in 16 patients (69.6%), accompanied by low HBV viremia. HDV-RNA and HBV-DNA levels showed no direct inverse correlation in the less part of the investigated patients, although higher HDV levels were accompanied by lower HBV viremia. HBV DNA correlates positively with HBeAg positivity. IFN is efficient in reducing transaminanses (ALT), decreasing HDV RNA levels at some point, but it is not operative in HDV RNA clearance. Lamivudine alone is a potent inhibitor of HBV DNA replication but does not improve disease activity or lower HDV RNA levels in patients with chronic delta hepatitis. It did not increase sustained virological response when combined with IFN. When virological breakthrough during Lamivudine therapy occurs, Tenofovir is a means of choice for treatment. Biochemical parameters did not accurately indicate the stage and grade of liver disease in chronic HDV patients as they often fluctuate over time.

176-177

Authors: Kuzucu, E. A., Çalışkan, E., Bayrak, Z. Ş., Önder, İ. T., Öcal, D., Erdem, G.

Streptococcus pneumoniae is not a common agent of urinary tract infection. Here we report a case of S. pneumoniae urinary isolate, which we thought might be important due to the urine analysis result, pure growth, and underlying diseases of patient.

182-188

Authors: Stoyanova, M., Valkova, M., Bogatzevska, N.

Tomato plants of all ages are susceptible to Clavibacter michiganensis subsp. michiganensis, Xanthomonas sp. and Pseudomonas syringae pv. tomato. Control is based mainly on copper-containing chemicalsand is often unsatisfactory. The object of this study was to test the effect of extracts from different, common for Bulgaria, medicinal and weed plants against referent strainsin vitro. Fresh plant aerial parts were oven-dried or freezed before extraction. Methanol and nhexane were used as solvents. Extractions were prepared in Soxhlet extractor at 80С/4h. Methanol and hexane were recovered in a vacuum evaporator. The fractions were diluted in water (%, w/v) with dimethylsulfoxide as dilution agent for some extracts. The in vitro test was completed by the agar diffusion method in triplicate with 50µl of each substance. The antimicrobial activity was assessed by measuring the diameter of the inhibition zone. A total of 25 plants and 47 methanol and n-hexane extracts were tested against the pathogenic bacteria of tomato. Extracts from seven plants have potential to be used against C. michiganensis subsp. michiganensis. Methanol extract from C. majus has the biggest potential for control of Xanthomonas of tomato and also has some effect against C. michiganensis subsp. michiganensis. H. spectabile has the potential to control all four bacteria but higher concentrations need to be tested. Methanol extract from Chaenomeles sp. has a good potential for control of all pathogens in concentrations of 5%.

194-197

Authors: Dikova, B.

Nepeta racemosa L. – or Persian catmint, is an aromatic plant species, used as a source for forming of perennial ornamental plantations. This plant is also useful for other reasons. It repels mosquitoes and cockroaches, because it contains nepetalactone, which has effects on some insects. Chlorotic spotting on the sprigs of the tufts of the perennial plantation of Persian catmint, originated from the trial field of the Institute of Rose, Essential and Medicinal Cultures near Kazanlak, was established in the period 2014-2017. The objective of the study was to establish the viral pathogen or several viral pathogens – agents of virus disease with chlorotic symptoms on the plants. The method used was ELISA, variant DASELISA. Two plant viruses were proven. One of them was Тоmato spotted wilt virus (TSWV) Bunyaviridae family, Tospovirus genus. It was established on N. racemosa in a high percentage of the chlorotic plants in the period 2014-2017. Therefore, TSWV existed in 91 % of the tested chlorotic plants in 2017. The second viral pathogen was Potato virus Y (PVY) – Potyviridae family, Potyvirus genus. PVY was for the first time established as a viral agent of disease on N. racemosa plants in the present study in 2017 together with TSWV . PVY existed in 27 % of the tested chlorotic plants.