Acta Microbiologica Bulgarica

Number 32(3), 2016

3-9
Oxidative Stress as a Target for Medication of Influenza Virus Infection

Authors: Mileva, M.

Abstract

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During influenza pandemics in the last few years many people have died from severe complications associated with this pandemic despite receiving intensive care. This suggests that a definitive medical treatment for severe influenza-associated complications has not yet been established. About the pathogenicity of flu, many studies have shown that superoxide anion produced by macrophages infiltrated into the virus-infected organs is implicated in the development of severe influenza-associated complications. Selected antioxidants, such as alpha-tocopherol, N-acetyl-L-cysteine, glutathione, ascorbic acid, 5,7,4-trihydroxy- 8-methoxyflavone, catechins, quercetin 3-rhamnoside, iso-quercetin etc. inhibit the proliferation of influenza virus and scavenge superoxide anions. The combination of antioxidants with antiviral drugs synergistically reduces the lethal effects of influenza virus infections. These results suggest that the combination of an agent with antiviral activities and an antioxidant could be a drug of choice for the treatment of patients with severe influenza-associated complications. Hopefully, this update of knowledge of antioxidant therapy of flu could be used as a potential approach to overcome the influenza-associated complications.

10-19
Phylogenetic Analysis of Ukrainian Isolates of RNA Viruses of Plants

Authors: Budzanivska, I. G., Shevchenko, T. P., Shevchenko, O. V., Polishchuk, V. P.

Abstract

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The availability of analytical approaches allowing fast deciphering of nucleotide sequences enables phylogenetic analysis of viruses and establishing homology among their strains/isolates for unveiling the history of virus evolution. This work was focused on phylogenetic analysis of the most important viruses infecting vegetable crops in Ukraine. ‘Field’ isolates of different plant RNA viruses were collected and analyzed from various agroecosystems. These included Potato virus Y (PVY), Cucumber mosaic virus (CMV), Watermelon mosaic virus 2 (WMV-2), Tomato mosaic virus (ToMV), Pepper mild mottle virus (PMMoV). Using MEGA6 software, phylogenetic trees were constructed, based on sequenced viral cDNAs corresponding to parts of the coat protein genes of the studied pathogens. Differing evolutionary trajectories were shown for some of the Ukrainian virus isolates. The study of the molecular properties of viruses, and especially those of viral genomes, has fundamental importance (tracing phylogenetic relationships of a given virus with other members of the kingdom, its evolutionary history and trends), and is also of practical significance, as such data may further be used both for developing highly specific PCR-based diagnostic techniques as well as for forecasting possible alterations and novel properties of circulating viruses for prevention of disease spread and minimizing the aggressiveness of viruses.

20-26
Studies on Malignant Catarrhal Fever in Wild Ruminants

Authors: Peshev, R., Hristov, M.

Abstract

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Wild and domestic animals inhabiting Sofia and Varna zoos showing clinical symptoms of malignant catarrhal fever (MCF) were investigated. Clinical and pathological studies were carried out with 16 wild and 8 domestic ruminants. Typical clinical symptoms for MCF were confirmed. Samples for virus isolation and molecular biological investigations were obtained from dead animals. Ten percent suspensions from the lymph nodes, spleens, lungs, brain samples, and buffy coats in phosphate buffered saline (PBS) were used for viral isolation. Primary and permanent cell cultures: rabbit kidney, Madin Darby bovine kidney (MDBK), embryonic bovine trachea (EBTR). Bovine trachea (TTr) and VERO cells were used. Viruses with peculiarities of herpesviruses were isolated from bison , yak, camel, Cameroon goats and hippopotamus on MDBK cell culture. The isolated strains were confirmed as MCF viruses by classical and nested polymerase chain reaction (PCR). The size of the amplicons after classical PCR was 422 bp, and 238 bp after nested PCR. Thirty seven serum samples originated from 17 sheep, 13 Cameroon goats, 5 mouflons and two bison were investigated serologically by a competitive-inhibition ELISA for spread of MCF. In 21.4% of sheep sera, 30.7% of Cameroon goat sera, and 50% of bison sera antibodies against MCF were found. The total distribution of MCF antibodies in wild and domestic ruminants was 27%.

27-32
Seroprevalence of Cytomegalovirus in the North-Eastern Bulgarian Population, 2003-2015

Authors: Stoykova, Z., Ivanova, L. I., Todorova, T. T., Kostadinova, T., Tsaneva-Damyanova, D.

Abstract

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Number of views: 152

The prevalence of cytomegalovirus (CMV) infections is between 50% and 85% in adults in different parts of the world. Its epidemiology varies on socioeconomic and age groups. The present retrospective study has been performed to determine the seroprevalence of CMV among the population in North-Eastern Bulgaria. For the period 2003–2015, the prevalence of individuals with antibodies to CMV was estimated, using indirect enzyme-linked immunosorbent assay (ELISA) to detect virus-specific IgG and IgM. The population sample included 7879 randomly chosen hospitalized patients of both sexes and different ages. The total seroprevalence of CMV was determined to be 78.4% (CI 95% 77.5; 79.3), and the relative proportion of acute CMV infections 22.9% (CI 95% 21.9; 23.7). The proportion of CMV IgG and IgM by sex and by age was also analysed. The results of the study reveal that CMV infection is highly prevalent among the population and occurs mainly in the first years of life.

33-38
Seroprevalence of Epstein-Barr Virus in North-Eastern Bulgaria

Authors: Kostadinova, T., Ivanova, L., Raykov, T., Stojkova, Z., Tsankova, G.

Abstract

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Number of views: 156

Epstein-Barr Virus (EBV) is a widely spread member of the Herpesviridae family. Data show that in more than 90% of the adult population, specific anti-EBV can be found. In different Bulgarian studies the seroprevalence was set between 60% and 80%. The primary infection early in life is often asymptomatic or with nonspecific clinical symptoms, while in teenagers infectious mononucleosis develops. EBV is a proven agent of malignant, autoimmune and lymphoproliferative diseases, especially in immunocompromised patients. Tracking and analyzing the seroepidemiological status of the population in every region is of utmost importance. In our study, 5016 single serum samples from patients referred for EBV testing for various reasons were analyzed for the period 2010-2015. People aged between 1 month and 89 years old were divided into sixteen age groups. The samples were tested using indirect enzyme-linked immunosorbent assay (ELISA) for detection of anti-EBV (VCA) IgM and IgG. The proportion of EBV seropositive individuals and their corresponding confidence intervals (CI), chi-squared distributions and p-values were calculated. Our data indicated high, age-dependent EBV (VCA) IgG dissemination with 90% seroprevalence after age 26. Primary infections detected by anti-EBV (VCA) IgM occur in a bimodal model with peaks in age groups 1 – 5 and 11 - 20 years old.

39-44
Investigation of the Antiviral and Antibacterial Potential of Coelomic Fluid from Some Earthworm Species (Oligochaeta: Lumbricidae)

Authors: Hinkov, А., Valchovski, H., Shishkov, S., Nedyalkova, K., Donkova, R.

Abstract

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Number of views: 165

The coelomic fluid of four earthworm species, Aporrectodea rosea, Eisenia fetida, Lumbricus terrestris and Octolasion lacteum, was investigated against Gram-negative bacteria strains: Aeromonas hydrophila, Pseudomonas fluorescens and Pseudomonas luteola and human pathogen Herpes simplex virus type 2 (genital herpes). The research revealed that only studied material from Eisenia fetida acted selectively on pathogenic bacteria. The greatest growth-inhibiting effect was observed on Aeromonas hydrophila. No antiviral potential was demonstrated against Herpes simplex virus. The metabolic components of the coelomic fluid have a strong cytolytic effect, but lack any activity against the tested virus pathogen.

45-48
Inhibiting Effect of Growth Regulators on Plant Viruses

Authors: Dikova, B., Balacheva, E., Moskova, I., Aleksieva, V.

Abstract

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Number of views: 153

The effect of the growth regulator β–monomethyl ester of itaconic acid (MEIA) on two economically important viruses, namely tomato spotted wilt virus (TSWV) and tomato mosaic virus (ToMV), was studied in tomato cultivars. Tomato plants of Keti and VK1 lines were infected separately with each virus: Keti with TSWV and ToMV, and VK1 with TSWV, respectively. The tomato plants were treated with MEIA in a concentration of 5x10-4 M after inoculation with TSWV in one variant, and with ToMV in another. An inhibiting effect was established on both viruses – TSWV and ToMV, when the tomato plants were infected and after that sprayed with MEIA solution. These initial results are a good reason to continue with the studies both for the establishment of the effect of growth regulators (MEIA in particular) on virus pathogens and the physiological indexes that prove the decrease in stress and injuries on tomato plants with virus diseases after treatment with MEIA..