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Abstract: Crust of carbonate minerals, named calcrete, underlies the arable soils of Southeast Bulgaria. The basic microorganism groups from soil, developed on top of a massive calcrete and in the rhizosphere of Cichorium intybus (Common chicory) were estimated by culturable methods. In this plant''s rhizosphere, microorganisms from some physiological groups were found in numbers 1 to 3 orders of magnitude higher, compared to non-rhizosphere samples of massive calcrete. The dominant microorganisms in this plant''s rhizosphere are represented by genera Bacillus. 16S rRNA gene nucleotide sequences were used for identification of four strains, obtained from the rhizospheres of C. intybus. The sequences obtained were compared to those of Bacillus species held in GenBank. The strains CI R1 and CI R3 were found to belong to the species Bacillus subtilis and the strains CI R2 and CI R4 to the species Bacillus amyloliquefaciens. Numerous studies confirm that these species are good facilitators of plant growth in nutrient deficient carbonate environment. Study of the growth‐promoting potential of these bacterial species, for economically important plants cultivated in this region, is currently in progress. [Copyright &y& Elsevier]

Few years ago the effectiveness of different Lactobacillus strains, with activity against different pathogens, was intensively studied. In particular, by producing metabolites such as acetic and lactic acid and thus lowering the pH, Lactobacillus strains inhibit the growth of bacterial pathogens and sometimes even kill them. In this study were included original Bulgarian dairy lactobacilli. The antibacterial activity against 8 test cultures and 8 clinical isolates was estimated by the agar diffusion method. We observed the inhibitory effect of growth of Bacillus subtilis, Bacillus alvei, Escherishia coli and Pseudomonas aeruginosa strains. The cells-free exponential cultures of non-neutralized (pH 3.9) and neutralized forms of the strain Lactobacillus sp. 50P1 showed highest activity. The active strain was identified as L. helveticus by classical and biochemical tests (API LAB 50CH kit). In addition to some technologically relevant properties the active strain 50P1 showed strong antibacterial effect against clinically isolated Pseudomonas aeruginosa and Bacillus alvei - an agricultural important bee pathogen. In conclusion, our results will form the basis for additional studies and possible further application of characterized L. helveticus 50P1 strain in clinical practice and/or veterinary medicine. [ABSTRACT FROM AUTHOR]

The article focuses on understanding the influence of the anthropomorphic thinking of Bulgarian children on their conceptions of the natural world. The authors aim to determine the dynamics of the conceptions of pre-school and primary school children. They state that there are differences in the literary images of plants and animals by the scientific description with children.

Human immunodeficiency virus (HIV) was originally introduced in Bulgaria through heterosexual transmission (HET) and later transferred to other vulnerable groups along with numerous more recent introductions from outside Bulgaria. To define the diversity, origins, and dynamics of the HIV-1 subtypes prevalent in HET population in Bulgaria, we applied phylogenetic and phylodynamic analyses using polymerase (pol) sequences from HET individuals to infer the spatiotemporal evolutionary history of the HIV-1 epidemic in this population in Bulgaria. High genetic diversity was found, including 13 different HIV-1 subtypes: 45.7% subtype B, 19.9% CRF01_AE, 7.5% CRF02_AG, 7.5% sub-subtypes A1 and A6, 7.1% subtype C, 5.3% subtype F1, 4.0% URFs, 1.2% CRF05_DF, 0.6% subtype G, 0.3% CRF04_cpx, 0.3% CRF29_BF, 0.3% CRF14_BG, and 0.3% subtype H. The estimated root of the subtype B in the phylogenetic tree dated back to the year 1980 largely due to multiple introductions of subtype B from outside the country. Several significant clades have been identified highlighting six different main epidemic entrances of subtype B dating from 1989 to 2007. The Bayesian skyline plot showed two different exponential growth periods starting in the 1980s to 1990 followed by a constant phase up to about 2008, with another exponential growth period from 2008 to the year 2012. The migration analysis identified dynamic pattern of gene flow and demonstrated that many HET probably acquired the infection abroad (14.6%), while only (6.6%) of non-HET were infected outside country. The phylogenetic analysis showed an intermixing between sequences from Bulgarians with sequences from other countries, suggesting different HIV introduction in this country followed by the internal spread through local transmission networks.

In recent years, there are numerous reports indicating the presence of familial papillary carcinoma. Unfortunately, no genetic defect can be linked directly to the disease. In this study, we set the goal to make a retrospective analysis of the cases with papillary carcinoma in the Department of Endocrine Surgery for the past 10 years, to compare the characteristics of sporadic and familial forms of the disease and to find families with hereditary papillary carcinoma. The study included 810 patients treated for thyroid cancer in the Department of Endocrine Surgery, USBALE "Acad. Iv. Penchev" Hospital, between January 1, 2006 and December 31, 2015. We used chi square test to determine statistical significant difference. The data analysis and interpretation was performed on SPSS 20.0. Both groups had similar demographic distribution. We found that 587 patients have sporadic papillary carcinoma, while 147 have a relative with thyroid pathology in the first degree of kinship. In 8 patients, there was a blood relative with thyroid cancer. When we compared the two groups, we found statistically significant difference only in tumor size. There was no significant difference in aggressiveness of the thyroid cancer (multifocality and lymph node metastasis). When analyzing the results, we identified 147 patients with a family history of thyroid disease (20%). In 8 patients (5.44%), we found at least one relative with papillary thyroid carcinoma. However, our study does not demonstrate any difference in the aggressiveness of familial and sporadic papillary thyroid carcinoma.

Objectives: To determine transmitted drug resistance (TDR) and HIV-1 genetic diversity in Bulgaria., Methods: The prevalence of TDR and HIV-1 subtypes was determined in 305/1446 (21.1%) persons newly diagnosed with HIV/AIDS from 1988 to 2011. TDR mutations (TDRMs) in protease and reverse transcriptase were defined using the WHO HIV drug mutation list. Phylogenetic analysis was used to infer polymerase (pol) genotype., Results: TDRMs were found in 16/305 (5.2%) persons, 11 (3.6%) with resistance to NRTIs, 5 (1.6%) with resistance to NNRTIs and 3 (0.9%) with resistance to PIs. Dual-class TDRMs were found in three (1.0%) patients and one statistically supported cluster of TDRMs comprising two individuals with subtype B infection. TDRMs were found in 10 heterosexuals, 4 MSM and two intravenous drug users. Phylogenetic analyses identified high HIV-1 diversity consisting of mostly subtype B (44.6%), subtype C (3.3%), sub-subtype A1 (2.6%), sub-subtype F1 (2.3%), sub-subtype A-like (3.6%), subtype G (0.3%), CRF14_BG (1.6%), CRF05_DF (1.3%), CRF03_AB (0.3%) and unique recombinant forms (1.3%)., Conclusions: We found a low prevalence of TDR against a background of high HIV-1 genetic diversity among antiretroviral-naive patients in Bulgaria. Our results provide baseline data on TDR and support continued surveillance of high-risk populations in Bulgaria to better target treatment and prevention efforts., (© The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Filamentous moulds are the main spoilage microorganisms, responsible for significant economic losses and several healthy risks in human food chain. The lactic acid bacteria (LAB), especially lactobacilli could be a natural antagonist of these dangerous organisms. In Bulgaria, a very limited data exists on the antifungal activity of LAB microbiota of fermented dairy products. In the present study, four active strains were isolated from traditional fermented curd/yogurt-like product "katak", produced in Bulgaria from centuries. The new isolates KR3, KR4, KR51 and KR53 were identified by API 50 CH biochemical test and different molecular methods (species-specific PCR, RAPD-PCR and 16S rDNA sequence analysis) as Lactobacillus brevis. According to our knowledge, this is the first data on the molecular characterization of the Lactobacillus microbiota of "katak". A broad spectrum of antifungal activity of the four L. brevis KR strains against test-cultures representatives of carcinogenic, toxigenic, deteriorative and allergenic fungi from the genera Aspergillus, Fusarium, Penicillium and Trichoderma was estimated. Strains L. brevis KR3, KR4 and KR51 completely suppress the growth of Penicillium claviforme, Aspergillus awamori and Aspergillus niger. With regard to Aspergillus flavus and Trichoderma viride, a lower and strain-specific inhibitory activity was observed. The antifungal activity of our new L. brevis isolates seems to be a promising advantage of these four strains, suggesting their potential applications in different food technologies as bio-preservative agents against moulds., (Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Limited information is available to describe the molecular epidemiology of HIV-1 in Bulgaria. To better understand the genetic diversity and the epidemiologic dynamics of HIV-1 we analyzed 125 new polymerase (pol) sequences from Bulgarians diagnosed through 2009 and 77 pol sequences available from our previous study from persons infected prior to 2007. Epidemiologic and demographic information was obtained from each participant and phylogenetic analysis was used to infer HIV-1 evolutionary histories. 120 (59.5%) persons were infected with one of five different HIV-1 subtypes (A1, B, C, F1 and H) and 63 (31.2%) persons were infected with one of six different circulating recombinant forms (CRFs; 01_AE, 02_AG, 04_cpx, 05_DF, 14_BG, and 36_cpx). We also for the first time identified infection with two different clusters of unique A-like and F-like sub-subtype variants in 12 persons (5.9%) and seven unique recombinant forms (3.5%), including a novel J/C recombinant. While subtype B was the major genotype identified and was more prevalent in MSM and increased between 2000-2005, most non-B subtypes were present in persons ≥45 years old. CRF01_AE was the most common non-B subtype and was higher in women and IDUs relative to other risk groups combined. Our results show that HIV-1 infection in Bulgaria reflects the shifting distribution of genotypes coincident with the changing epidemiology of the HIV-1 epidemic among different risk groups. Our data support increased public health interventions targeting IDUs and MSM. Furthermore, the substantial and increasing HIV-1 genetic heterogeneity, combined with fluctuating infection dynamics, highlights the importance of sustained and expanded surveillance to prevent and control HIV-1 infection in Bulgaria.

The essential oils of two species of Sideritis growing spontaneously in Bulgaria and Macedonia are reported, Sideritis scardica and Sideritis raeseri. The oils of S. scardica from different locations differed significantly: in the Macedonian sample alpha-cadinol (20%) predominated, while in the oil of Bulgarian samples the main components were diterpenic compounds and octadecenol (over 20%). This is the first report of ditrpenoids in essential oil of S. scardica. The oil of S. raeseri demonstrated a distinct chemical profile with its high concentration of sesquiterpenes, main components being germacrone (25%) and elemol acetate (15.9%). The observed qualitative variability of the oil composition of S. scardica of different geographic origin could be a result of different ecologic conditions but might also reflect the well-known tendency of some Sideritis species to hybridize.

The quick increase of morbidity, caused by the endometrial carcinoma in our country during recent 15 years from 5,2 to 16,5 per 100,000 raises acutely the question about effective primary and secondary prophylaxis. Having in mind the role of hyperestrogenemia in the etiology of endometrial carcinoma and the fact that the results from its treatment are determined basically by the degree of distribution of the tumor, the authors think that it is necessary fight for rational feeding, timely treatment of the disease with hyperestrogenemia and prophylactic therapy with gestagens. Cytologic examination of aspirate, obtained from the uterine cavity, is proposed as screening method for women of the risk groups. A scheme of management of women with pathological R3-5 group is proposed.