11 results on '"Petkova, V."'
Search Results
2. Cardiac troponin elevation and mortality in takotsubo syndrome: New insights from the international takotsubo registry.
- Author
-
Stähli BE, Schindler M, Schweiger V, Cammann VL, Szawan KA, Niederseer D, Würdinger M, Schönberger A, Schönberger M, Koleva I, Mercier JC, Petkova V, Mayer S, Citro R, Vecchione C, Bossone E, Gili S, Neuhaus M, Franke J, Meder B, Jaguszewski M, Noutsias M, Knorr M, Jansen T, D'Ascenzo F, Dichtl W, von Lewinski D, Burgdorf C, Kherad B, Tschöpe C, Sarcon A, Shinbane J, Rajan L, Michels G, Pfister R, Cuneo A, Jacobshagen C, Karakas M, Koenig W, Pott A, Meyer P, Roffi M, Banning A, Wolfrum M, Cuculi F, Kobza R, Fischer TA, Vasankari T, Airaksinen KEJ, Napp LC, Dworakowski R, MacCarthy P, Kaiser C, Osswald S, Galiuto L, Chan C, Bridgman P, Beug D, Delmas C, Lairez O, Gilyarova E, Shilova A, Gilyarov M, El-Battrawy I, Akin I, Poledniková K, Toušek P, Winchester DE, Massoomi M, Galuszka J, Ukena C, Poglajen G, Carrilho-Ferreira P, Hauck C, Paolini C, Bilato C, Kobayashi Y, Kato K, Ishibashi I, Himi T, Din J, Al-Shammari A, Prasad A, Rihal CS, Liu K, Schulze PC, Bianco M, Jörg L, Rickli H, Pestana G, Nguyen TH, Böhm M, Maier LS, Pinto FJ, Widimský P, Felix SB, Braun-Dullaeus RC, Rottbauer W, Hasenfuß G, Pieske BM, Schunkert H, Budnik M, Opolski G, Thiele H, Bauersachs J, Horowitz JD, Di Mario C, Kong W, Dalakoti M, Imori Y, Liberale L, Montecucco F, Münzel T, Crea F, Lüscher TF, Bax JJ, Ruschitzka F, Ghadri JR, Di Vece D, and Templin C
- Abstract
Background: The clinical relevance of cardiac troponin (cTn) elevation in takotsubo syndrome (TTS) remains uncertain. The present study sought to investigate the role of cardiac troponin (cTn) elevations in mortality prediction of patients with Takotsubo syndrome (TTS)., Methods: Patients enrolled in the International Takotsubo (InterTAK) Registry from January 2011 to February 2020 with available data on peak cTn levels were included in the analysis. Peak cTn levels during the index hospitalization were used to define clinically relevant myocardial injury. The threshold at which clinically relevant myocardial injury drives mortality at 1 year was identified using restricted cubic spline analysis., Results: Out of 2'938 patients, 222 (7.6%) patients died during 1-year follow-up. A more than 28.8-fold increase of cTn above the upper reference limit was identified as threshold for clinically relevant myocardial injury. The presence of clinically relevant myocardial injury was significantly associated with an increased risk of mortality at 5 years (adjusted HR 1.58, 95% CI 1.18-2.12, p =.002). Clinically relevant myocardial injury was related to an increased 5-year mortality risk in patients with apical TTS (adjusted HR 1.57, 95% CI 1.21-2.03, p =.001), in presence of physical stressors (adjusted HR 1.60, 95% CI 1.22-2.11, p =.001), and in absence of emotional stressors (adjusted HR 1.49, 95% CI, 1.17-1.89, p =.001)., Conclusion: This study for the first time determined a troponin threshold for the identification of TTS patients at excess risk of mortality. These findings advance risk stratification in TTS and assist in identifying patients in need for close monitoring and follow-up., (© 2024 Stichting European Society for Clinical Investigation Journal Foundation. Published by John Wiley & Sons Ltd.)
- Published
- 2024
- Full Text
- View/download PDF
3. A Study of the Influence of Thermoactivated Natural Zeolite on the Hydration of White Cement Mortars.
- Author
-
Stoyanov V, Petkova V, Mihaylova K, and Shopska M
- Abstract
One trend in the development of building materials is the partial or complete replacement of traditional materials that have a high carbon footprint with eco-friendly ecological raw materials and ingredients. In the present work, the influence of replacing cement with 10 wt% thermally activated natural zeolite on the structural and physical-mechanical characteristics of cured mortars based on white Portland cement and river sand was investigated. The phase compositions were determined by wavelength dispersive X-ray fluorescence (WD-XRF) analysis, X-ray powder diffraction (PXRD), diffuse reflectance infrared Fourier transformed spectroscopy (DRIFTS), and scanning electron microscopy (SEM), as well as thermogravimetric analysis simultaneously with differential scanning calorimetry (TG/DTG-DSC). The results show that the incorporation of zeolite increases the amount of pores accessible with mercury intrusion porosimetry by about 40%, but the measured strengths are also higher by over 13%. When these samples were aged in an aqueous environment from day 28 to day 120, the amount of pores decreased by about 10% and the compressive strength increased by nearly 15%, respectively. The microstructural analysis carried out proves that these results are due to hydration with a low content of crystal water and the realization of pozzolanic reactions that last over time. Replacing some of the white cement with thermally activated natural zeolite results in the formation of a greater variety of crystals, including new crystalline CSH and CSAH phases that allow better intergrowth and interlocking. The results of the investigations allow us to present a plausible reaction mechanism of pozzolanic reactions and of the formation of new crystal hydrate phases. This gives grounds to claim that the replacement of part of the cement with zeolite improves the corrosion resistance of the investigated building solutions against aggressive weathering.
- Published
- 2024
- Full Text
- View/download PDF
4. Co-expression of miRNA players in advanced laryngeal carcinoma - Insights into the roles of miR-93-5p, miR-145-5p, and miR-210-3p.
- Author
-
Kyurkchiyan S, Petkova V, Stancheva G, Stancheva I, Dimitrov S, Dobriyanova V, Popova D, Kaneva R, and Popov TM
- Abstract
Advanced laryngeal squamous cell carcinoma (LSCC) is the second most prevalent type of head and neck squamous cell carcinoma (HNSCC). Identifying microRNAs (miRNAs) related to key regulatory molecules or mechanisms could offer an alternative approach to developing new treatment strategies. The aim of our study is to evaluate significant correlations among deregulated miRNAs in advanced laryngeal carcinoma and to analyze, in silico, their strength of association, targets, and the most deregulated pathways. Several miRNAs demonstrated promising co-expression results, specifically miR-93-5p, miR-145-5p, and miR-210-3p. Their expressions were explored and further validated in a large set of in vivo advanced LSCC samples, which were subsequently used for bioinformatics and enrichment analyses. Our results highlight the significant roles of miR-93-5p, miR-145-5p, and miR-210-3p in regulating major pathways linked to the cell cycle via epithelial-to-mesenchymal transition (EMT), PI3K/Akt signaling, hypoxia, metabolism, apoptosis, angiogenesis, and metastasis. The associations between the expressions of these miRNAs and patients' clinical features could be central to the progression of advanced LSCC. Overall, our study provides important insights into the co-expression and regulatory networks of miR-93-5p, miR-145-5p, and miR-210-3p in advanced laryngeal carcinoma, underscoring their potential as therapeutic targets or biomarkers for this aggressive cancer. Further research is needed to elucidate the specific mechanisms through which these miRNAs contribute to the pathogenesis and progression of laryngeal carcinoma.
- Published
- 2024
- Full Text
- View/download PDF
5. Density Functional Theory Prediction of Laser Dyes-Cucurbit[7]uril Binding Affinities.
- Author
-
Petkova V, Dobrev S, Kircheva N, Nazarova D, Nedelchev L, Nikolova V, Dudev T, and Angelova S
- Abstract
Among a variety of diverse host molecules distinguished by specific characteristics, the cucurbit[n]uril (CB) family stands out, being widely known for the attractive properties of its representatives along with their increasingly expanding area of applications. The presented herewith density functional theory (DFT)-based study is inspired by some recent studies exploring CBs as a key component in multifunctional hydrogels with applications in materials science, thus considering CB-assisted supramolecular polymeric hydrogels (CB-SPHs), a new class of 3D cross-linked polymer materials. The research systematically investigates the inclusion process between the most applied representative of the cavitand family CB[7] and a series of laser dye molecules as guests, as well as the possible encapsulation of a model side chain from the photoanisotropic polymer PAZO and its sodium-containing salt. The obtained results shed light on the most significant factors that play a key role in the recognition process, such as binding mode, charge, and dielectric constant of the solvent. The observed findings provide valuable insights at a molecular level for the design of dye-CB[7] systems in various environments, with potential applications in intriguing and prosperous fields like photonics and material science.
- Published
- 2024
- Full Text
- View/download PDF
6. Naphthalimide-Based Amphiphiles: Synthesis and DFT Studies of the Aggregation and Interaction of a Simplified Model System with Water Molecules.
- Author
-
Petkova V, Anastasova D, Dobrev S, Mutovska M, Kircheva N, Nikolova V, Kolev SD, Stoyanov S, Zagranyarski Y, Dudev T, and Angelova S
- Abstract
Systems containing amphiphilic/pathic molecules have the tremendous capacity to self-assemble under appropriate conditions to form morphologies with well-defined structural order (systematic arrangement), nanometer-scale dimensions, and unique properties. In this work, the synthesis of novel naphthalimide-based amphiphilic probes that have 1,8-naphthalimide as the fluorescence signal reporting group, octyl as hydrophobic head, and PEG as hydrophilic tail, is described. These designed molecules represent a new class of self-assembling structures with some promising features. The lack of literature data on the use of 1,8-naphthalimides with cyclic and acyclic hydrophilic PEG fragments as self-assembling structures gives us the opportunity to initiate a new field in materials science. The successful synthesis of such structures is fundamental to synthetic chemistry, and computational studies of the aggregation and binding of water molecules shed light on the ability of these new systems to function as membrane water channels. This study not only expands the list of 1,8-naphthalimide derivatives but may also serve as a new platform for the development of membrane additives based on PEG-functionalized naphthalimides.
- Published
- 2024
- Full Text
- View/download PDF
7. Rare host variants in ciliary expressed genes contribute to COVID-19 severity in Bulgarian patients.
- Author
-
Kamenarova K, Kachakova-Yordanova D, Baymakova M, Georgiev M, Mihova K, Petkova V, Beltcheva O, Argirova R, Atanasov P, Kunchev M, Andonova R, Zasheva A, Drenska R, Ivanov I, Pantileeva D, Koleva V, Penev A, Lekova-Nikova D, Georgiev D, Pencheva D, Bozhilova R, Ivanova N, Dimova I, Plochev K, Popov G, Popivanov I, Gabrovsky N, Leseva M, Mitev V, and Kaneva R
- Subjects
- Humans, Bulgaria, Female, Male, Middle Aged, Aged, Adult, Mutation, Cilia pathology, Cilia genetics, COVID-19 genetics, COVID-19 virology, COVID-19 pathology, SARS-CoV-2 genetics, SARS-CoV-2 isolation & purification, Exome Sequencing, Severity of Illness Index
- Abstract
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), a pneumonia with extremely heterogeneous clinical presentation, ranging from asymptomatic to severely ill patients. Previous studies have reported links between the presence of host genetic variants and the outcome of the COVID-19 infection. In our study, we used whole exome sequencing in a cohort of 444 SARS-CoV-2 patients, admitted to hospital in the period October-2020-April-2022, to search for associations between rare pathogenic/potentially pathogenic variants and COVID-19 progression. We used gene prioritization-based analysis in genes that have been reported by host genetic studies. Although we did not identify correlation between the presence of rare pathogenic variants and COVID-19 outcome, in critically ill patients we detected known mutations in a number of genes associated with severe disease related to cardiovascular disease, primary ciliary dyskinesia, cystic fibrosis, DNA damage repair response, coagulation, primary immune disorder, hemoglobin subunit β, and others. Additionally, we report 93 novel pathogenic variants found in severely infected patients who required intubation or died. A network analysis showed main component, consisting of 13 highly interconnected genes related to epithelial cilium. In conclusion, we have detected rare pathogenic host variants that may have influenced the COVID-19 outcome in Bulgarian patients., (© 2024. The Author(s).)
- Published
- 2024
- Full Text
- View/download PDF
8. Exploration of the association between HIF3α mRNA and lncRNA MALAT1 in laryngeal squamous cell carcinoma by correlation analysis.
- Author
-
Kyurkchiyan SG, Stancheva G, Petkova V, Hadzhiev Y, Dobriyanova V, Popova D, Kaneva R, and Popov TM
- Abstract
Laryngeal squamous cell carcinoma (LSCC) is a significant global health burden, for which there has been limited evidence of improved survival rates. Although the roles of hypoxia-inducible factor (HIF)1α and HIF2α have been well documented in hypoxia, the involvement of HIF3α, particularly in LSCC, has been inadequately explored. The present study aimed to investigate the correlation between HIFα subunits and the hypoxia-related long noncoding RNAs (lncRNAs) MALAT1 and HOTAIR in 63 patients diagnosed with LSCC. Total RNA was extracted from fresh-frozen laryngeal tumor and adjacent normal tissues, and was subjected to reverse transcription-quantitative PCR for target detection. Statistical analyses were conducted using SPSS software, with significance set at P<0.05. The present study is the first, to the best of our knowledge, to report a positive moderate monotonic correlation (rs=0.347) and moderately strong positive linear correlation (r=0.630) between HIF3α mRNA and lncRNA MALAT1 in LSCC. Regression analysis revealed a direct association between 39.6% of both variables. Additionally, a positive correlation was observed between lncRNAs MALAT1 and HOTAIR (rs=0.353); HIF2α mRNA and lncRNA MALAT1 (rs=0.431); HIF3α mRNA and lncRNA HOTAIR (rs=0.279); and HIF3α mRNA and HIF2α mRNA (rs=0.285). Notably, a significant negative correlation (rs=-0.341) was detected between HIF3α mRNA and HIF1α mRNA, potentially indicative of the HIF switch or negative regulation. In addition, the present study investigated the association between HIFα subunits and the clinicopathological characteristics of patients. The results revealed a notable association between HIF1α transcript levels and the location of LSCC; specifically, subglottic tumors exhibited elevated HIF1α levels compared with glottic and supraglottic LSCC. Furthermore, a significant association was identified between HIF3α transcript levels and patient age (P=0.032) and positive family history (P=0.047). In conclusion, the present findings suggested a pivotal role for HIF3α in LSCC development, potentially involving direct regulation of lncRNA MALAT1. However, further research is warranted to elucidate its precise mechanisms., Competing Interests: The authors declare that they have no competing interests., (Copyright: © 2024 Kyurkchiyan et al.)
- Published
- 2024
- Full Text
- View/download PDF
9. Evaluation of respiratory allergies burden and management in primary care and comparative analysis of health care data from Romania, Poland, Czech Republic and Bulgaria - preliminary study.
- Author
-
Leru PM, Anton VF, Chovancova Z, Baros J, Socha K, Petkova V, and Kurowski M
- Subjects
- Humans, Romania epidemiology, Surveys and Questionnaires, Bulgaria epidemiology, Male, Female, Asthma therapy, Asthma epidemiology, Poland epidemiology, Rhinitis, Allergic therapy, Rhinitis, Allergic epidemiology, Czech Republic epidemiology, Adult, Middle Aged, Respiratory Hypersensitivity epidemiology, Respiratory Hypersensitivity therapy, Respiratory Hypersensitivity diagnosis, Cost of Illness, Primary Health Care
- Abstract
Background: Respiratory allergies mostly allergic rhinitis and asthma represent an important and increasing public health problem and one of the priorities for the European health systems. There is an increasing public concern regarding the persistence and severity of allergic diseases and many difficulties of health systems in providing prompt specialized medical assistance. Our study aims to highlight the main results of the Alliance 4Life project focused on the evaluation of the burden and management of respiratory allergies in primary care from Romania and comparative health-related data from four Central and Eastern European countries., Method: We developed a questionnaire focused on patients with allergic rhinitis and asthma directly addressed to general practitioner (GP) specialists from Romania who attended the annual national conference in Bucharest., Results: The main results showed that patients with respiratory allergies are frequently encountered in primary care practice, only a few patients are evaluated by allergists and there is a clear need for education in this field., Conclusions: This preliminary study confirms that respiratory allergies represent a considerable burden in primary care and the questionnaire may be a useful tool in further studies considering the experience of other healthcare systems. More advanced studies integrating epidemiology with data on air pollution and environmental conditions should be envisaged., (© 2024 Polliana Mihaela Leru et al., published by Sciendo.)
- Published
- 2024
- Full Text
- View/download PDF
10. In Silico Analysis of the Ga 3+ /Fe 3+ Competition for Binding the Iron-Scavenging Siderophores of P. aeruginosa -Implementation of Three Gallium-Based Complexes in the "Trojan Horse" Antibacterial Strategy.
- Author
-
Kircheva N, Dobrev S, Petkova V, Yocheva L, Angelova S, and Dudev T
- Subjects
- Oligopeptides chemistry, Oligopeptides metabolism, Thiazoles chemistry, Thiazoles metabolism, Thiazoles pharmacology, Computer Simulation, Coordination Complexes chemistry, Coordination Complexes pharmacology, Coordination Complexes metabolism, Pyrones chemistry, Pyrones metabolism, Pyrones pharmacology, Gallium chemistry, Gallium metabolism, Pseudomonas aeruginosa drug effects, Pseudomonas aeruginosa metabolism, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents chemistry, Siderophores chemistry, Siderophores metabolism, Iron metabolism, Iron chemistry, Organometallic Compounds, Phenols
- Abstract
The emergence of multidrug-resistant (MDR) microorganisms combined with the ever-draining antibiotic pipeline poses a disturbing and immensely growing public health challenge that requires a multidisciplinary approach and the application of novel therapies aimed at unconventional targets and/or applying innovative drug formulations. Hence, bacterial iron acquisition systems and bacterial Fe
2+/3+ -containing enzymes have been identified as a plausible target of great potential. The intriguing "Trojan horse" approach deprives microorganisms from the essential iron. Recently, gallium's potential in medicine as an iron mimicry species has attracted vast attention. Different Ga3+ formulations exhibit diverse effects upon entering the cell and thus supposedly have multiple targets. The aim of the current study is to specifically distinguish characteristics of great significance in regard to the initial gallium-based complex, allowing the alien cation to effectively compete with the native ferric ion for binding the siderophores pyochelin and pyoverdine secreted by the bacterium P. aeruginosa . Therefore, three gallium-based formulations were taken into consideration: the first-generation gallium nitrate, Ga(NO3 )3 , metabolized to Ga3+ -hydrated forms, the second-generation gallium maltolate (tris(3-hydroxy-2-methyl-4-pyronato)gallium), and the experimentally proven Ga carrier in the bloodstream-the protein transferrin. We employed a reliable in silico approach based on DFT computations in order to understand the underlying biochemical processes that govern the Ga3+ /Fe3+ rivalry for binding the two bacterial siderophores.- Published
- 2024
- Full Text
- View/download PDF
11. Peritumor Mucosa in Advanced Laryngeal Carcinoma Exhibits an Aberrant Proangiogenic Signature Distinctive from the Expression Pattern in Adjacent Tumor Tissue.
- Author
-
Kyurkchiyan SG, Stancheva G, Petkova V, Panova S, Dobriyanova V, Stancheva I, Marinov V, Zahariev Z, Kaneva RP, and Popov TM
- Subjects
- Humans, Neovascularization, Pathologic genetics, Mucous Membrane, Basic Helix-Loop-Helix Transcription Factors metabolism, Laryngeal Neoplasms genetics, Carcinoma
- Abstract
The field cancerization theory is an important paradigm in head and neck carcinoma as its oncological repercussions affect treatment outcomes in diverse ways. The aim of this study is to assess the possible interconnection between peritumor mucosa and the process of tumor neoangiogenesis. Sixty patients with advanced laryngeal carcinoma were enrolled in this study. The majority of patients express a canonical HIF-upregulated proangiogenic signature with almost complete predominancy of HIF-1α overexpression and normal expression levels of the HIF-2α isoform. Remarkably, more than 60% of the whole cohort also exhibited an HIF-upregulated proangiogenic signature in the peritumoral benign mucosa. Additionally, the latter subgroup had a distinctly shifted phenotype towards HIF-2α upregulation compared to the one in tumor tissue, i.e., a tendency towards an HIF switch is observed in contrast to the dominated by HIF-1α tumor phenotype. ETS-1 displays stable and identical significant overexpression in both the proangiogenic phenotypes present in tumor and peritumoral mucosa. In the current study, we report for the first time the existence of an abnormal proangiogenic expression profile present in the peritumoral mucosa in advanced laryngeal carcinoma when compared to paired distant laryngeal mucosa. Moreover, we describe a specific phenotype of this proangiogenic signature that is significantly different from the one present in tumor tissue as we delineate both phenotypes, quantitively and qualitatively. This finding is cancer heterogeneity, per se, which extends beyond the "classical" borders of the malignancy, and it is proof of a strong interconnection between field cancerization and one of the classical hallmarks of cancer-the process of tumor neoangiogenesis.
- Published
- 2024
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.