INTRODUCTION Radiofrequency catheter ablation of idiopathic ventricular arrhythmias originating in the para-Hisian region could be challenging because of a potential risk of iatrogenic atrioventricular block. Uncommonly, shift of the exit site during the ablation can be observed. Consequently, different approaches of radiofrequency catheter ablation of para-Hisian ventricular foci can be needed. CASE SERIES PRESENTATION Three patients (2 males) underwent electroanatomical mapping and catheter ablation for idiopathic premature ventricular contractions originating near the His bundle. Patients underwent 24-h ECG Holter monitoring during follow-up. All patients had premature ventricular contractions with left bundle branch block morphology and inferior or horizontal axis. However, change of QRS morphology during ablation was observed, due to a change in the exit site. In two patients there was reduction of the arrhythmia burden after initially unsuccessful procedure. Mapping and ablation in the aortic root were needed in one patient. There were no complications. DISCUSSION Radiofrequency catheter ablation of para-Hisian ventricular arrhythmias is feasible and safe when performed cautiously. A change in the premature ventricular contractions’ morphology and exit site during ablation may ensue; therefore, extensive mapping on both sides of the interventricular septum as well as in the aortic root may be warranted. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.INTRODUCTION Due to the high prevalence of viral infections having no specific treatment and the constant emergence of resistant viral strains, searching for effective antiviral compounds is crucial. The present study explores in vitro the antiviral activity of ethanolic extract from aerial parts of. AIM The aim of the current study was to evaluate antiviral activity of ethanolic extract from herbaceous plant. MATERIALS AND METHODS The crude aqueous ethanolic extract from aerial parts of. RESULTS The results show that the extract has the lowest toxicity on the MDBK cell line and similar cytotoxicity in Hep-2, whereas in the MDCK cells it has more than twice the highest toxicity. Testing the antiviral activity of. CONCLUSION The crude extract from aerial parts of the medicinal plant. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.BACKGROUND The manufacture of medicinal products for human use in the European Economic Area is governed by European Directives and Regulations stipulating the relevant principles and guidelines of Good Manufacturing Practice, describing the minimum standard to be fulfilled in the production processes. AIM To present analysis of the deficiencies reported following Good Manufacturing Practice inspections in Bulgaria in two consecutive years (2016, 2017) and to compare them with results from similar inspections reported by other EU member states. MATERIALS AND METHODS A retrospective study was carried out by reviewing the complete Good Manufacturing Practice inspection reports of all manufacturers conducted by the Bulgarian Drug Agency in 2016 and 2017, according to relevant requirements and applicable local legislation. The items reviewed were scope of inspection, type of companies, classification of deficiencies – ‘critical’, ‘major’ and ‘other significant deficiencies’, their nature and reference to EU Good Manufacturing Practice. RESULTS The analyzed data included 55 inspections, revealing 460 various deficiencies, of which 2 were critical and 102 – major. Twenty inspections were performed in 2016 vs. 35 inspections in 2017. The pattern of deficiencies was similar to the findings of other EU regulatory agencies, showing that equivalent requirements were applied. Our analysis showed that Bulgarian Drug Agency inspectors rarely raised deficiencies related to Computer Systems, Qualification/Validation, Personnel and Qualification of Suppliers unlike other EU regulators agents. CONCLUSIONS Our analysis of Good Manufacturing Practice inspection findings in 2016 and 2017 showed that the Bulgarian Drug Agency demonstrated its ability to detect non-compliances and take necessary regulatory actions. Quality related issues constitute the main reasons for non-compliances with the requirements. This is an open access article distributed under the terms of the CC0 Public Domain Dedication.INTRODUCTION Dental caries is among the most important social diseases. The changes in caries prevalence occurring in different regions provide important information about the influence of etiological factors – primary and secondary, and about understanding the connections between the factors themselves. AIM The aim of this study was to investigate the prevalence of dental caries in 12-year-old children from Plovdiv, Bulgaria and the effect of etiological factors – single-factor and multifactorial influence. MATERIALS AND METHODS The study included 228 children divided into 2 groups group 1 – children living in the city of Plovdiv, city proper (125 children), and group 2 – children living in the surrounding villages (103 children). A questionnaire with an attached written consent form for clinical examination was completed by the parents of each child with results recorded in the WHO Oral Health Assessment Form for Children. Statistical analysis of the recorded data was used to determine DMFT index for the two groups, percentage of caries-free children and the influence of etiological factors through regression analysis. RESULTS Statistical analysis showed the DMFT scores as follows – 1.568 for city proper, 2.917 for surrounding villages. The caries-free children were 38.4% and 17.5% for group 1 and group 2, respectively. OHI is the highest predicting factor in a multifactorial regression analysis with over 19% predictive function. CONCLUSION There was statistically significant difference in caries prevalence and percentage of caries-free children between the city proper and the surrounding villages. Etiological factors have specific influence in the investigated age group. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.AIM The objective of this study was to carry out an in vivo investigation of patients wearing dentures relined with soft materials, assuming their positive and negative alterations in time. MATERIALS AND METHODS A direct survey method was used to gather data from 23 patients included in this study (11 male and 12 female patients). Twenty-seven dentures were made (12 partial and 15 total dentures) 9 of which in chairside procedures, 11 – in a laboratory, and 7 were made using the direct-indirect method. Patients were included in regular follow-ups at one month and six months, and at one, two, and three years after dentures delivery. The study started in 2014 and continued till 2017. RESULTS AND DISCUSSION All participants completed questionnaires which included questions related to changes in retention and stability of the relined dentures, changes in color and softness, in bond strength, and inflammation. CONCLUSION There were no significant differences in the behavior of the different groups of materials at six months. After six months we observed decline in the bond strength of the vinyl-polysiloxane (VPS) materials, as well as increased staining and hardness in the poly-methyl-methacrylate (PMMA). This is an open access article distributed under the terms of the CC0 Public Domain Dedication.BACKGROUND Dental students are at high risk of developing adverse respiratory reactions as a result of their practical work during their dentistry degree program when they come into contact with multiple airborne irritants and allergens. AIM To estimate the prevalence of respiratory symptoms of exposure to substances in the workplace and associated risk factors in Bulgarian dental students. RESULTS The prevalence of self-reported respiratory symptoms related to the pre-clinical and clinical training courses of the dentistry program was 12.4%. According to logistic regression analysis, the most important risk factors for work-related respiratory symptoms were a personal history of allergic rhinoconjunctivitis (odds ratio (OR) 6.34, 95% confidence interval (CI) 3.14-12.78), atopic dermatitis (OR 2.81, 95%CI 1.26-6.26), and exposure to chemicals from dental environment for more than 6 hours a day (OR 3.60, 95%CI 1.21-10.70). CONCLUSION The results of this study suggest that work-related respiratory symptoms are frequent among dental students and indicate the need for efforts to establish effective primary preventive programs for occupational respiratory disorders at national level. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.BACKGROUND Broncho-pleural fistula (BPF) can occur after pulmonary resections as a complication with high morbidity and mortality rates. AIM In the present study, we analyzed the relation between the possible risk factors and the two major bronchial closure techniques for BPF after lung resections, and the management methods of BPF. MATERIALS AND METHODS A total of 26 cases detected and managed with BPF diagnosis in our clinic between September 2005 and September 2017 were evaluated retrospectively. The cases were divided into two groups Group 1 (n=14); bronchial closure performed manually and Group 2 (n=12) bronchial closure with stapler. We analyzed cases for age, gender, body mass index, pulmonary function tests, time to fistula, total protein/albumin level, length of hospital stay, bronchial stump distance, presence of bronchial stump coverage, and the mean survivals. RESULTS Twenty-three of the cases were males (88.5%) with a mean age of 60.03±8.7 years (range 38-73). While BPF was detected in twenty-thre (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.INTRODUCTION 2-AAF and DEN are well-known liver toxicants commonly used to stimulate tumors in laboratory animals. AIM The aim of this study was to investigate the effect of octreotide on DEN-induced and 2-AAF-supplemented hepatocarcinogenesis in Wistar albino rats. MATERIALS AND METHODS In this study, 64 Wistar albino rats were divided into 8 groups. DEN (175 mg/kg) initiated and 2-AAF (20 mg/kg) promoted liver carcinogenesis in rats. The tumor growth inhibitor octreotide (300 μg/kg) was used. Rats were sacrificed at the end of experiment and their liver tissues were taken for the study. SOD, GSH-Px, CAT activities, NO and MDA levels were measured spectrophotometrically. Also, Hsp70 and 8-OHdG was measured by the ELISA method. RESULTS In group 7, MDA, 8-OHdG, and Hsp70 levels were significantly increased. In addition, SOD, GSH-Px activity was significantly reduced in this group. MDA, 8-OHdG and Hsp70 levels were significantly reduced in Group 8, which received octreotide for treatment. CONCLUSION DEN and 2-AAF cause very serious liver damage.