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  • Author: D. Ivanova x
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The critical thickness (hcr) for foam films of n-dodecyl β-D maltoside (C12G2) and of its mixed solutions with dodecanol (C12Е0), hexaethyleneglycol dodecyl ether (C12E6) and dodecyl trimethylammonium bromide (C12TAB) of different molar ratio (50:1; 1:1;1:50) at low and high ionic strength was measured interferometrically. It was found that the hcr increases with the increase of the film radius independently of solutions composition. At low ionic strength the type of surfactant affects the critical thickness and the equilibrium state of the film. hcr for the films of mixture with C12E0 increases with the increase of the total surfactant concentration, while hcr for the films of mixture with C12TAB decreases. For the values of the critical thicknesses for films from individual surfactant solutions the following sequence hcr (C12TAB) > hcr (C12E6) > hcr (C12G2) is found. At high ionic strength the quantity of nonionic additive does not substantially affect the value of hcr, while the quantity of ionic additive influences it by two different ways (i) in 50:1 mixture C12TAB supports C12G2 in the reducing of negative charge; (ii) in 1:1 mixture C12TAB recharges the film surfaces.


Pure and nitrogen-doped titanium dioxide (N-doped TiO2) photocatalysts were prepared by non-aqueous sol-gel method by means of the reaction between titanium (IV) chloride (TiCl4) and C6H5CH2 OH (benzyl alcohol), used as precursors and urea serving as a nitrogen source. The phase formation and short-range order of the resulting particles were characterized by X-ray powder diffraction (XRD) and infrared (IR) spectroscopy. The crystallite size of as-prepared composite powders was in the range 12-35 nm. The aim of this work was to investigate the efficiency of N-doped TiO2 as a photocatalyst in degradation of model organic pollutants - dyes Reactive Black 5 (RB5) and Malachite Green (MG), under ultraviolet (UV) and visible (Vis) irradiation. 0ur results indicated that synthesized N-TiO2 nanocomposites slightly improved the photocatalytic activity under UV irradiation, compared to the pure titanium dioxide (TiO2), and had no effect under Vis light illumination.


Wilson’s disease is an inherited autosomal recessive disorder of copper balance leading to accumulation of copper mainly in liver and brain result from absent or reduced function of copper-transporting P-type ATPase. Copper is an essential trace element but in Wilson’s disease it accumulate to the point of toxicity. D-penicillamine is a classic drug for treatment of Wilson’s disease. Its major effect is to promote the urinary copper excretion. The use of D-penicillamine in the therapy of Wilson’s disease is known to be complicated by the development of various glomerular diseases. In this report we describe the development of nephrotic syndrome after 2 years treatment with D-penicillamine in a 31-year-old male undergoing treatment for Wilson’s disease, with a prompt regression at the discontinuation of the drug. We present this case to draw attention to the rare complication as nephrotic syndrome in patients with Wilson’s disease under D-penicillamine treatment and possible underlying causes. It is strongly necessary the therapy and clinical condition of patients with Wilson’s disease to be monitoring regularly - we recommended monthly.


INTRODUCTION: Violent behaviour may be an appropriate response to a given set of environmental conditions in nature. Social organizations as power systems ensure stability through force or threat. However, there is a growing concern about the violence against health service staff in both hospitals and outpatient facilities.

AIM: To study the frequency, types and determinants of patient violence towards health professionals in primary care in Bulgaria and to fi nd the specifi c characteristics of violent behaviour in patient subgroups as well as the attitudes of providers.

MATERIAL AND METHODS: A sample of 165 doctors from primary care institutions in Bulgaria participated in a questionnaire study using a specially developed research tool.

RESULTS: Prevalence of violent patient behaviour has not been studied extensively in Bulgaria leaving a gap in research data. The participating physicians, however, reported that there is a serious increase in the frequency and diversity of aggressive behaviour towards medical profession by patients and negative attitude of the general public indicating serious issues in public health care.

CONCLUSION: Most often patients’ aggression was provoked by factors associated with the health system organization and effectiveness and the socio-economic status of the population.


Background: Human cytomegalovirus is a ubiquitous, large enveloped DNA β-herpesvirus that, like other herpesviruses, establishes lifelong latency following primary infection. It is the most frequent cause of congenital, neonatal and early postnatal infections with long lasting sequelae.

Aim: The aim of the present study was to assess the prevalence of cytomegalovirus among a cohort of newborns and 1-3-month-old children with neurological symptoms, physical retardation, prolonged jaundice, thrombocytopenic purpura and other disabilities.

Materials and methods: The study was a retrospective cross-sectional analysis of serological screening data for detection of specific anti-cytomegalovirus IgM and IgG in children from Northeastern Bulgaria.

Results: Between 2003 and 2015, average prevalences of 18.8% (95% CI: 15.4 to 22.2) for anti-CMV IgM antibodies (suggesting acute infection) and 84.7% (95% CI: 81.6 to 87.8) for anti-CMV IgG antibodies were measured in a total number of 517 samples. The prevalence rate of anti-CMV IgM in 1-3-month-old children was 4-fold higher than that in newborns [25.8% (95% CI: 21.1 to 30.5) and 6.4% (95% CI: 2.9 to 9.9, respectively]. In contrast, no significant difference was found for anti- CMV IgG positivity between newborns and 1-3-month-old infants (84% and 85%, respectively).

Conclusions: The data obtained strongly encourage screening of pregnant women for anti-CMV IgG and IgM to avoid transmission of the infection and severe complications of congenital infection.


Gestational diabetes mellitus (GDM), one of the most common pregnancy complications, is defined as glucose intolerance with onset or first recognition during pregnancy. Its prevalence varies worldwide in dependence on characteristics of the underlying population and applied diagnostic criteria. The etiology is multifactorial and not sufficiently elucidated. Available evidence suggests that the base of pathogenesis is relatively diminished insulin secretion coupled with pregnancy-induced insulin resistance. Modifiable and non-modifiable risk factors for development have been identified. Trace elements and vitamin D could be contributed to modifiable factors for prediction the risk in a large population. Essential trace elements in pregnancy are necessary to overcome systemic oxidative, metabolic and inflammatory stress. Evidence, still inconclusive, has been accumulated about the relation between higher incidence of vitamin D failure/deficiency during pregnancy and GDM. The lower level of 25-OH vitamin D could be associated with increased risk for anemia development, also including pregnant women. This review intends to provide an overview of the possible link between both vitamin D and trace elements as risk factors for GDM development.


Serum lipids abnormalities are widespread among patients with chronic hepatitis C (CHC), but the impact of concomitant hepatic steatosis [steatosis, nonalcoholic steatosis (NAS)], as well as distinctions between it and nonalcoholic fatty liver disease (NAFLD) are not well established yet. The aim of the study was to assess and compare the serum lipids in patients with genotype 1 CHC with and without steatosis, those with NAFLD, and healthy controls (HC). A total of 1010 subjects were included in this study: 366 CHC genotype 1 patients with steatosis (n = 227) and without steatosis (n = 139), 403 NAFLD patients, and 241 HC without fatty liver or other disease, matched for age and gender. Serum lipids, body mass index (BMI), components of metabolic syndrome (MS), and serum insulin levels were evaluated. In addition serum lipoprotein (a) [Lp(a)] levels were studied in 112 CHC and 80 NAFLD patients. The mean levels of total cholesterol, LDL-cholesterol and triglycerides (Tg) were higher and the mean levels of HDL-cholesterol were lower in all patients with steatosis (CHC and NAFLD) than in CHC cases without steatosis (p < 0.05 and p = 0.001, resp.). Higher prevalence and severity of lipid abnormalities, including Lp(a), were observed in patients with NAFLD than in those with CHC (p < 0.001). No difference was found between CHC patients without steatosis and HC. Higher prevalence and grade of glucose metabolic abnormalities were also observed in patients with NAFLD and CHC with steatosis than in cases without steatosis (p < 0.05 and p = 0.001, resp.). Lipid and glucose metabolic abnormalities in patients with CHC were dependent on steatosis. CHC with steatosis and NAFLD were associated with insulin resistant type dyslipidemia, with total cholesterol and LDL-cholesterol being generally lower in CHC.


Crohn's disease (CD) may have some severe complications that pose an increasing health burden and negatively impact the quality of life. There are two major types - intestinal and extraintestinal complications, in which immune and non-immune mechanisms take place. We aimed to search for some associations between specific extraintestinal manifestation and intestinal complications in CD patients with some clinicallaboratory findings, immunological markers, and the therapy administered. We examined retrospectively medical files of 26 patients with CD at mean age 42 ± 13 years, including the laboratory results. The immunological markers fecal calprotectin (FC) and fecal lactoferrin (FL) were assessed in frozen fecal samples of the chosen patients. Seventy-three percent of the investigated CD patients had some extraintestinal manifestation and/or intestinal complications, at least 13/26 had intestinal complications. All three patients with extraintestinal signs were positive for FC and 2/3 were positive for FL. We observed a higher serum level of CRP (24.49 mg/l vs. 3.13 mg/l, p = 0.010), slightly lowered serum level of hemoglobin (120 g/l vs. 145 g/l, p = 0.044) and about 2-fold lower iron level (7.23 μmol/l vs. 14.0 μmol/l, p = 0.019) in patients with intestinal complications compared to patients without complications, respectively. Four out of thirteen patients with intestinal complications were without immunosuppressive therapy at the time of our study, and nine out of thirteen - on immunosuppressive drugs. Routine laboratory and immunology testing could be beneficial for gastroenterologists in identifying patients at high risk for the development of complications and in the decision making for more aggressive therapy early after diagnosis.


Rabbits and rats were inoculated with material derived from FLK cells producing permanently bovine leukaemia virus (BLV). The viral presence in the inoculum was proved by transmission electron microscopy, immunofluorescence, immunogold labelling demonstrating viral Tax protein, and PCR analysis. About 30 % of the infected animals sustained BLV seropositivity during the experiment, and demonstrated symptoms of lympholeukaemia - clinical manifestation of an immunosuppressive condition, increased number of lymphocytes and lymphoblasts, and preneoplastic lymphoid cell accumulations in the liver, lungs, kidneys, and lymph nodes. BLV DNA, detected by PCR in diseased animals, indicates the role of BLV as an aetiological factor of lympholeukaemia, developed in these animals after BLV infection. The alterations in rats were more pronounced than those in rabbits. The results prove that these two species of laboratory animals, especially rats, are suitable models for the in vivo studies of leukaemogenesis caused by BLV/HTLV infections.


Background: Bronchial asthma is a heterogeneous disease that includes various subtypes. They may share similar clinical characteristics, but probably have different pathological mechanisms.

Aim: To identify phenotypes using cluster analysis in moderate to severe bronchial asthma and to compare differences in clinical, physiological, immunological and inflammatory data between the clusters.

Patients and methods: Forty adult patients with moderate to severe bronchial asthma out of exacerbation were included. All underwent clinical assessment, anthropometric measurements, skin prick testing, standard spirometry and measurement fraction of exhaled nitric oxide. Blood eosinophilic count, serum total IgE and periostin levels were determined. Two-step cluster approach, hierarchical clustering method and k-mean analysis were used for identification of the clusters.

Results: We have identified four clusters. Cluster 1 (n=14) - late-onset, non-atopic asthma with impaired lung function, Cluster 2 (n=13) - late-onset, atopic asthma, Cluster 3 (n=6) - late-onset, aspirin sensitivity, eosinophilic asthma, and Cluster 4 (n=7) - early-onset, atopic asthma.

Conclusions: Our study is the first in Bulgaria in which cluster analysis is applied to asthmatic patients. We identified four clusters. The variables with greatest force for differentiation in our study were: age of asthma onset, duration of diseases, atopy, smoking, blood eosinophils, nonsteroidal anti-inflammatory drugs hypersensitivity, baseline FEV1/FVC and symptoms severity. Our results support the concept of heterogeneity of bronchial asthma and demonstrate that cluster analysis can be an useful tool for phenotyping of disease and personalized approach to the treatment of patients.