Search Results

You are looking at 1 - 8 of 8 items for

  • Author: M. Petrov x
Clear All Modify Search
Open access

Miroslav Petrov

Abstract

This paper presents three methods for multiscale indexing of the content of projection data of computed tomography images in the CBIR-systems for medical database search. The feature spaces in the developed algorithms have been created by means of, respectively: Discrete Stationary Wavelet Transform (DSWT), Shearlet Transform (ST) and Repagulum Wavelet Transform (RWT). A comparative analysis and assessment of the proposed algorithms have been carried out based on experimental studies with computed tomography images.

Open access

Savelina L. Popovska, Tatyana M. Betova and Кrasimir T. Petrov

Abstract

Fibromatoses are a group of benign proliferations of fibrous tissue with clinical behaviour ranging from that of truly malignant tumours to that of benign reactive fibrous proliferations. Some of the superficial fibromatoses are fairly common but deep ones, also known as desmoid tumours or musculoaponeurotic fibromatoses, are rare. We describe a case of extra-abdominal musculo- aponeurotic fibromatosis in a 22-years old male. He underwent 14 operations for a period of 9 years for fibromatosis of the posterior surface of the right lower limb. The histological findings of the lesions were similar consistent across surgeries and consistent with a diagnosis of aggressive extra-abdominal fibromatosis.

Open access

Sava V. Petrov, Maria M. Orbetzova, Yanko T. Iliev and Doychin T. Boyadzhiev

Abstract

Introduction: Drug addictions to psychoactive substances are disorders with a complex bio-psycho-social genesis, which are characterized with chronic relapses. Substance addiction causes multifactorial damage to the normal functioning of individuals and requires a multicenter approach for the treatment process.

Aim: The aim of the study was to assess the quality of life of patients undergoing chronic treatment with the opiate agonist methadone using a standardized questionnaire method in Bulgarian.

Material and methods: The study included patients aged 18 to 40 years undergoing chronic treatment with methadone for at least six months. The study included 100 subjects. Seventy-six patients were from 5 clinical programs in Bulgaria; twenty- four clinically healthy age-matched subjects with no history of drug abuse, psychiatric and somatic diseases were the control group.

Results: We found significant differences between patients and controls in all components of the survey (P<0.05). The patients had lower scores than the control group in the SF-36 in terms of all eight components and both the physical and mental component summaries of the SF-36-survey. Patients compared between the groups by dose, duration of treatment with methadone and period of heroin abuse before initiating treatment did not show significant differences. There were no significant differences between patients with and without hepatitis C virus.

Conclusions: Opiate addiction is a state associated with poor quality of life. The duration of treatment, the methadone dose, period of heroin abuse before initiating treatment and illness of hepatitis C virus does not correlate with lower results.

Open access

Ivo S. Petrov, Mariya P. Tokmakova, Daniel N. Marchov and Kostadin N. Kichukov

Abstract

Introduction: Tako-tsubo syndrome is a novel cardio-vascular disease affecting predominantly postmenopausal women exposed to unexpected strong emotional or physical stress, in the absence of significant coronary heart disease. It is characterized by acute onset of severe chest pain and/or acute left ventricular failure, ECG-changes, typical left ventricular angiographic findings, good prognosis and positive resolution of the morphological and clinical manifestations. First described in 1990 in Japan by Sato, Tako-tsubo cardiomyopathy is characterized by transient contractile abnormalities of the left ventricle, causing typical left ventricular apical ballooning at end-systole with concomitant compensatory basal hyperkinesia. There are also atypical forms, presenting with left ventricular systolic dysfunction which affects the mid-portions of the left ventricle.

The etiology of the disease still remains unclear. Many theories have been put forward about the potential underlying pathophysiological mechanisms that may trigger this syndrome among which are the theory of catecholamine excess, the theory of multivessel coronary vasospasm, the ischemic theory, and the theory of microvascular dysfunction and dynamic left ventricular gradient induced by elevated circulating catecholamine levels.

Adequate management of Tako-tsubo syndrome demands immediate preparation for coronary angiography. Once the diagnosis is made, treatment is primarily symptomatic and includes monitoring for complications. Patients with Tako-tsubo syndrome most frequently develop acute LV failure, pulmonary edema, rhythm and conductive disturbances and apical thrombosis. Treatment is symptomatic and includes administration of diuretics, vasodilators and mechanical support of circulation with intra-aortic balloon counterpulsation.

Open access

Eugenia Petrova, C. Dumitrache, Andra Buruiana, Maria Olaru, Irina Popescu, Nicoleta Dumitru, M. Ghemigian, B. Petrov and Adina Ghemigian

ABSTRACT

Vitamin D deficiency is a global health problem, its role as an immune modulator being recently emphasized. Recent studies are increasingly suggesting that vitamin D plays a significant role in reducing the incidence and progression of autoimmune diseases. Furthermore, it was reported that patients with Hashimoto’s thyroiditis, an autoimmune thyroid disease had lower vitamin D levels [1].

We initiated a prospective study, for a period of 6 months with a study group represented by 160 patients admitted to the National Institute of Endocrinology “CI Parhon” in the period 2013 -2014. Patients were divided into 3 groups: 121 patients without thyroid pathology, 22 patients diagnosed with chronic autoimmune thyroiditis, who received 2000 IU cholecalciferol daily, 17 patients diagnosed with chronic autoimmune thyroiditis, which did not receive cholecalciferol.

We found that patients with chronic thyroiditis have a poor vitamin D status with ATPO values negatively correlating with 25 (OH) vitamin D levels. Treatment with cholecalciferol not only improves vitamin D status but also lowers antithyroid antibodies titres. Keywords: vitamin D deficiency, chronic

Open access

I. Ganchev, S. Ahmed, A. Taneva and M. Petrov

Abstract

This paper presents a fuzzy-neural structure of a Decoupling Fuzzy PID controller with self-tuning parameters. This structure is appropriate for Two-Input-Two-Output (TITO) nonlinear system. The main advantage here is that the equation of classical PID control and decoupling coefficients are used as a Sugeno function into the fuzzy rules. Hence the designed decoupling fuzzy PID controller can be viewed as a natural similarity to the conventional one with decoupling elements. A benchmark quadruple tank, implementing a TITO nonlinear system is considered to illustrate the benefits of the design paradigm. The performance of this set up was studied for reference tracking and disturbance rejection cases. Simulation results confirm the effectiveness of the proposed solution.

Open access

Atanaska P. Petrova, Irina D. Stanimirova, Ivan N. Ivanov, Michael M. Petrov, Tsonka M. Miteva-Katrandzhieva, Vasil I. Grivnev, Velichka S. Kardjeva, Todor V. Kantardzhiev and Mariana A. Murdjeva

Abstract

Background: Production of Bla OXA-23, OXA-24, OXA-58 and hyperexpression of OXA-51 due to ISAba1 insertion sequence are the leading causes of carbapenem resistance in Acinetobacter baumannii. The loss of OprD transmembrane protein and the overexpression of some effl ux pumps are considered to be the main factors for carbapenem resistance in Pseudomonas aeruginosa whereas metallo-enzymes’ production has a secondary role. Aim: Тo examine the carbapenem resistance due to carbapenemase production among clinically signifi cant Gram-negative non-fermenters from St George University hospital, Plovdiv: A. baumannii and P. aeruginosa. Materials and methods: Forty three A. baumannii and 43 P. aeruginosa isolates, resistant or with intermediate resistance to imipenem and/or meropenem were included in the study. They were collected from patients admitted in 14 various hospital wards between 2010 and 2014. Both phenotypic and genetic methods were used for identifi cation and antimicrobial susceptibility testing. Results: All A. baumannii demonstrated carbapenemase production determined by a modifi ed Hodge test whereas P. aeruginosa isolates did not show this phenomenon. OXA-23 genes were determined in 97.7% (42 out of 43) of A. baumannii isolates indistinguishable from the sequence of the classical ARI-1 gene. OXA-24, OXA-58 and overexpression of OXA-51 were not registered in any of the isolates. All P. aeruginosa were negative for blaVIM and blaIMP genes. Conclusion: The leading cause of carbapenem resistance in A. baumannii isolates from our hospital is the carbapenemase production due to the expression of OXA- 23 gene, whereas in P. aeruginosa - the loss of transmembrane OprD protein and the effl ux pumps’ hyperexpression are suspected to be the main mechanisms.

Open access

Maria R. Pavlova, Elina G. Dobreva, Katucha I. Ivanova, Galina D. Asseva, Ivan N. Ivanov, Peter K. Petrov, Valeri R. Velev, Ivelina I. Tomova, Maida M. Tiholova and Todor V. Kantardjiev

Abstract

Introduction: Campylobacter spp. are important causative agents of gastrointestinal infections in humans. The most frequently isolated strains of this bacterial genus are Campylobacter jejuni and Campylobacter coli. To date, genetic methods for bacterial identification have not been used in Bulgaria. We optimized the multiplex PSR assay to identify Campylobacter spp. and differentiate C. jejuni from C. coli in clinical isolates. We also compared this method with the routinely used biochemical methods.

Aim: To identify Campylobacter spp. and discriminate C. coli from C. jejuni in clinical isolates using multiplex PCR assay.

Materials and methods: Between February 2014 and January 2015 we studied 93 stool samples taken from patients with diarrheal syndrome and identified 40 species of Campylobacter spp. in them. The clinical material was cultured in microaerophilic atmosphere, the isolated strains being biochemically diff erentiated (hydrolysis of sodium hippurate for C. jejuni, and hydrolysis of indoxyl acetate for C. coli). DNA was isolated from the strains using QiaAmp MiniKit (QIAGEN, Germany). Twenty strains were tested with multiplex PCR for the presence of these genes: cadF, characteristic for Campylobacter spp., hipO for C. jejuni and asp for C. coli.

Results and discussion: The biochemical tests identified 16 strains of C. jejuni, 3 strains of C. coli, and 1 strain of C. upsaliensis. After the multiplex PCR assay the capillary gel electrophoresis confirmed 16 strains of C. jejuni, 2 strains of C. coli and 2 strains of Campylobacter spp. - because of the presence of the gene cadF. C. jejuni has the gene hipO, and it is possible that this gene may not be expressed in the biochemical differentiation yielding a negative reaction as a result. In comparison, we can conclude that the genetic differentiation is a more accurate method than the biochemical tests.

Conclusion: The multiplex PCR assay is a fast, accurate method for identifi cation of Campylobacter spp. which makes it quite necessary in the clinical diagnostic practice.