68 results on '"Stanislava Ivanova"'
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2. Essential oils – a review of the natural evolution of applications and some future perspectives
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Stanislava Ivanova, Yana Gvozdeva, Radiana Staynova, Daniela Grekova-Kafalova, Vanya Nalbantova, Niko Benbassat, Nina Koleva, and Kalin Ivanov
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Pharmacy and materia medica ,RS1-441 - Abstract
Since ancient times, essential oils (EOs) have been used, thoroughly explored, and regarded as products of great importance for humanity. Currently, EOs represent not only an important part of the contemporary pharmaceutical and cosmetic industry but are also considered as sources for novel drug candidates. The article discusses the applications of EOs in historical terms, the current applications, and the future perspectives. Although there are many studies that involve EOs, the therapeutic potential of EOs is not fully investigated. In the next decades it is highly likely that some compounds, isolated from EOs, could be included in the composition of novel drug candidates with targets in neurology, cardiology, or oncology. Moreover, EOs represent important key points in the development of novel environmentally friendly preservatives and pesticides.
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- 2025
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3. GC-MS analysis of cholesterol lowering dietary supplements
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Velislava Todorova, Diana Karcheva-Bahchevanska, and Stanislava Ivanova
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cholesterol ,antihyperlipidemic ,dietary supplements ,gc-ms ,Pharmacy and materia medica ,RS1-441 - Abstract
Controlling cholesterol levels and reducing the risk of cardiovascular disease requires the development of effective therapeutic strategies. In recent decades, dietary supplements (DSs) have gained attention as potential additions to conventional cholesterol management therapies, but their efficacy and safety are questionable. Accurate methods are required to evaluate the efficacy and safety of DSs. In the current study gas chromatography mass spectrometry was performed to analyze ten cholesterol-reducing DSs. The results showed that monacolin K/lovastatin was present in four samples. Moreover, using effective doses generally has minimal risks and lower incidence of adverse reactions and drug interactions. However, it must be taken into account the potential interaction of statins to induce myopathy and rhabdomyolizis. In order to prevent adverse effects, it is necessary to thoroughly evaluate and be careful when using DSs containing monacolin K.
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- 2024
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4. Lepidium meyenii biological activity and future perspectives
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Zoya Dzhakova, Diana Karcheva-Bahchevanska, and Stanislava Ivanova
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adaptogens ,plant adaptogens ,lepidium meyenii ,maca root ,macamides ,macaene ,Pharmacy and materia medica ,RS1-441 - Abstract
Lepidium meyenii Walp. (Brassicaceae) is a plant native to the Andean region. It is also known as Maca and Peruvian ginseng and is considered to have been used in traditional medicine for more than 2000 years. Lepidium meyenii is regarded as a plant adaptogen. Nowadays, Maca root is used worldwide as a food, tonic, antioxidant, enhancer of fertility, etc. The main compounds in the underground part of the plant are glucosinolates, thiohydantoins, isothiocyanates, macamides, macaene, fatty acids, polysaccharides, alkaloids, fiber, lipids and proteins, which are responsible for various biological activities including antimicrobial, antioxidant, cytotoxic, anti-inflammatory and immunomodulatory activities. The purpose of this review is to summarize the data of some in vitro, in vivo and clinical studies on the biological activity of Maca and to analyze the future perspectives for the inclusion of Maca into novel herbal medicines
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- 2024
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5. Salicornia europaea L. and Suaeda maritima (L.) Dumort: bioactive compounds and future perspectives
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Velina Dzhoglova, Kalin Ivanov, Diana Karcheva-Bahchevanska, Nina Koleva, Maria Bozhkova, Niko Benbassat, and Stanislava Ivanova
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Salicornia europaea L ,Suaeda maritima ,salt-tolerant plants ,halophyte ,bioactive compounds ,phytochemicals ,Biotechnology ,TP248.13-248.65 - Abstract
Halophyte plants have a phytochemical composition that results from the harsh conditions characteristic of their specific habitats. These plants have been used since ancient times because of the various biological activities which they possess. The aim of this review is to evaluate the main bioactive compounds and to outline the future therapeutic applications of two halophyte plants in Bulgaria. Studies on the phytochemical composition and biological activities of Salicornia europaea L. and Suaeda maritima (L.) Dumort are included. These halophyte plants are found along the Black Sea coast around salt lakes and marshes in Bulgaria. The data obtained indicate that these plants exhibit hepatoprotective, antineoplastic, antioxidant, anti-inflammatory, antidepressant, antimicrobial and antiviral biological activities, and their extracts have promising potential for inclusion in functional foods, dietary supplements and novel herbal pharmaceuticals.
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- 2024
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6. Development and validation of a high-performance thin-layer chromatography method for detection of sibutramine in dietary supplements
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Vanya R. Kozhuharov, Dzhevdet Chakarov, Stanislava Ivanova, and Kalin Ivanov
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Medicine - Abstract
Introduction: In the period between 1997 and 2010, sibutramine-containing drugs were widely prescribed for obesity and over-weight management. Due to safety concerns, in 2010 all medicines containing sibutramine were urgently withdrawn from the USA and European pharmaceutical market. Although sibutramine is no longer available in pharmaceutical products, there have been numerous reports of mislabeled weight-loss dietary supplements containing sibutramine. Aim: This work aimed to develop and validate an accurate and sensitive high-performance thin-layer chromatographic method for the detection of sibutramine. Materials and methods: The method was developed using a CAMAG HPTLC system. Silica gel 60 F254 aluminum HPTLC plates were used as stationary phase and toluene:ethyl acetate:methanol (7:2:1 v/v/v) as mobile phase. Results: The calibration curve was built in the range of 0.250–1.250 μg/band. The method provided satisfactory linearity, specificity, precision, and accuracy. The LOD and the LOQ were 0.0765 μg/band and 0.2318 μg/band, respectively. Conclusions: The method allows for the simultaneous analysis of multiple samples as well as the rapid and sensitive monitoring of sibutramine levels in dietary supplements.
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- 2024
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7. Evaluation of the Influence of Tanacetum vulgare Extract on Cognitive Functions and Hippocampal BDNF Expression
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Borislava Lechkova, Michaela Shishmanova-Doseva, Niko Benbassat, Reneta Gevrenova, Pepa Atanassova, Nadya Penkova, Lyudmil Peychev, Petar Hrischev, Zhivko Peychev, and Stanislava Ivanova
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Tanacetum vulgare ,cognitive functions ,anxiolytic activity ,BDNF ,hippocampus ,Organic chemistry ,QD241-441 - Abstract
Tanacetum vulgare L. has been traditionally applied as a remedy for headaches, rheumatism, digestion, respiratory and neurological problems, and other medical conditions. However, the literature data on its effects on cognitive function are scarce. The aim of the present work was to evaluate the effects of two doses of T. vulgare alcohol extract on cognitive functions, hippocampal brain-derived neurotrophic factor (BDNF) expression, and organ toxicity in rats. Rats were treated with T. vulgare 200 mg/kg (TV 200) and 1000 mg/kg (TV 1000) for 28 days. After one week of pre-treatment, the animals were subjected to a series of tests. We found that in the active avoidance test, only TV 200 improved learning and memory, while in the passive avoidance test, both doses facilitated these processes. In addition, the two doses enhanced spatial memory. In the elevated plus maze test, only the higher dose of TV 1000 resulted in anxiolytic-like behavior. Both doses of the extract significantly increased the hippocampal expression of BDNF. We suggest that increased neurotrophic factor expression could be one of the important mechanisms underlying the cognition-enhancing effects of T. vulgare extract.
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- 2024
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8. Genus Stachys—Phytochemistry, Traditional Medicinal Uses, and Future Perspectives
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Stela Pashova, Diana Karcheva-Bahchevanska, Kalin Ivanov, and Stanislava Ivanova
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Stachys ,traditional medicine ,phytochemistry ,phytopharmaceuticals ,Organic chemistry ,QD241-441 - Abstract
The genus Stachys represents one of the most extensive genera within the subfamily Lamioideae and ranks as one of the largest genera in the Lamiaceae family. Many Stachys species are associated with a rich history in traditional medicine across various cultures, and their extracts and essential oils are rich in non-volatile and volatile compounds. Because of their complex profile of bioactive substances, Stachys members are considered to possess an extensive spectrum of therapeutic properties, including antioxidant, anti-inflammatory, analgesic, antibacterial, cytotoxic, and wound-healing effects, as well as benefits for memory enhancement, lipid profile regulation, blood glucose control, and weight management. Despite the wide distribution and chemical diversity of the genus, studies on its biological activities remain limited. The aim of this review is to summarize the most relevant data from studies on the bioactive compounds, traditional uses, and pharmacological properties of Stachys species found in databases such as Science Direct, PubMed, and Scopus. Specific keywords were used in the search strategy, including “bioactive compounds”, “Stachys”, “Lamiaceae”, “Stachys extract”, “Stachys essential oil”, “traditional uses”, “chemical composition”, “therapeutic potential”, “clinical trials”, “in vivo studies”, “in vitro studies”. The search strategy was performed according to the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Data from 171 studies were included. The manuscript highlights the drug-discovery potential of Stachys species, emphasizing their potential applications in medicine, cosmetics, dietary supplements, and the food industry. Moreover, it provides important data that could assist Stachys research programs.
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- 2024
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9. Phytoecdysteroids: Quantification in Selected Plant Species and Evaluation of Some Effects on Gastric Smooth Muscles
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Velislava Todorova, Stanislava Ivanova, Viktor Yotov, Ekaterina Zaytseva, Raina Ardasheva, Valentin Turiyski, Natalia Prissadova, and Kalin Ivanov
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phytoecdysteroids ,20-hydroxyecdysterone ,Rhaponticum carthamoides Wild. ,quinoa ,kaniwa ,spinach ,Organic chemistry ,QD241-441 - Abstract
Phytoecdysteroids (PEs) are naturally occurring steroid compounds, that have recently gained significant attention, due to their diverse biological activities and high therapeutic potential. The aim of the present study was to quantify some PEs including 20-hydroxyecdysterone (20-HE), ponasterone A (PA), and turkesterone (TU) in selected plant foods and Rhaponticum carthamoides extract. Furthermore, the effects of 20-HE, TU, and R. carthamoides extract, were investigated with in vitro methods using isolated smooth muscle tissues. The levels of 20-HE in the analyzed samples exhibited significant differences, with kaniwa seed extract containing the highest amount, followed by spinach leaf extract, quinoa seed extract, and asparagus stem extract. The in vitro analyses suggested that R. carthamoides extract exhibits dose-dependent cytotoxic effects on smooth muscle cells, with low doses promoting contraction and higher doses inducing relaxation. Additionally, the extract demonstrated a significant inhibitory effect on ACh-induced contractions, while 20-HE enhanced the contractile response. The current findings highlighted phytoecdysteroids’ potential for modifying gastrointestinal motility.
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- 2024
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10. Salvia verticillata (L.)—Biological Activity, Chemical Profile, and Future Perspectives
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Stanislava Ivanova, Zoya Dzhakova, Radiana Staynova, and Kalin Ivanov
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Salvia verticillata ,Salvia ,essential oils ,folk medicine ,phytopharmaceuticals ,β-caryophyllene ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
Species belonging to the genus Salvia, Lamiaceae, have been deeply involved in the folk medicine of different nations since ancient times. Lilac sage, or Salvia verticillata L. (S. verticillata) is a less studied species from the genus. However, it seems to have a prominent potential for the future drug discovery strategies of novel phytopharmaceuticals. This review aims to summarise the data on the biological activity and the phytochemical profile of extracts and essential oils derived from S. verticillata. This review is based on data from 57 in vitro and in vivo studies. The chemical profile of S. verticillata includes different synergic compounds like phenolic acids, flavonoids, terpenes, and salvianolic acids. Although some small amounts of salvianolic acid B were found in S. verticillata extracts, the major compound among the salvianolic acids is salvianolic acid C, a compound associated with the potential for improving liver fibrosis, cardio- and hepatoprotection, and the inhibition of SARS-CoV-2 infection. The cannabinoid type 2 receptor agonist β-caryophyllene is one of the major compounds in S. verticillata essential oils. It is a compound with a prominent potential in regenerative medicine, neurology, immunology, and other medical fields. The in vivo and the in vitro studies, regarding S. verticillata highlighted good antioxidant potential, anti-inflammatory, antibacterial, and antifungal activity. S.verticillata was also reported as a potential source of drug candidates for the treatment of neurodegenerative diseases such as Alzheimer’s disease, because of the inhibitory activity on the acetylcholinesterase. However, the number of studies in this direction is limited.
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- 2024
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11. Genus Echinophora—Biological Activity, Chemical Composition, and Future Perspectives
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Stanislava Ivanova, Stanislav Dyankov, Rayna Ardasheva, and Kalin Ivanov
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Echinophora ,traditional medicine ,novel drugs ,phytopharmaceuticals ,Botany ,QK1-989 - Abstract
Species belonging to the genus Echinophora (Apiaceae) have been used by humanity since ancient times as flavoring agents, preservatives, and medicines for the treatment of a broad spectrum of conditions, including respiratory, digestive and kidney disorders, fungi infections, wounds, and gastric ulcers. Phytochemical studies on this botanical genus mainly investigate the essential oil composition and reveal the species as a rich source of volatile compounds, including monoterpenes and phenylpropanoids. Among the non-volatile secondary metabolites, flavonoids, coumarins, phenolic acids, phytosterols, and polyacetylenes have been identified. Pharmacological studies revealed Echinophora extracts and essential oils exhibit different biological properties, including antibacterial, antifungal, anticancer, insecticidal, anti-inflammatory, and hepatoprotective activities. However, compared to other genera, the biological activity and chemical diversity of this genus are not well studied. In future decades, it is highly likely that the small genus Echinophora will play an important role in drug discovery and drug development.
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- 2024
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12. Comparative study of the chemical composition of Trigonella foenum-graecum L. essential oil
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Vanya Nalbantova, Niko Benbassat, Cédric Delattre, Velislava Todorova, Yoana Georgieva, Paolina Lukova, Stanislava Ivanova, Kalin Ivanov, and Diana Karcheva-Bahchevanska
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Pharmacy and materia medica ,RS1-441 - Abstract
Fenugreek is a well-known aromatic plant. Its leaves and seeds are commonly used for their many health benefits and the species is cultivated worldwide. For the first time, essential oils (EOs) from seeds of the Bulgarian and Indian populations were obtained by secondary distillation of hydrolat to extract the residual essential oil therein. They were analyzed by gas chromatography-mass spectrometry and the chemical composition of the two samples was compared. Thirty-six compounds were identified and although the results showed some differences in the component composition of the two essential oils, the major constituents identified in both oils were cubenol, γ-n-amylbutyrolactone and palmitic acid. Moreover, oxygenated sesquiterpenes were the predominant fraction in Bulgarian and Indian seeds oils. Information is limited regarding menthol and γ-n-amylbutyrolactone, which were found in the present study in both oils. The performed analysis confirmed the presence of phytol in fenugreek seeds regardless of the extraction method of the essential oil.
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- 2023
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13. Enhanced Solubility of Ibuprofen by Complexation with β-Cyclodextrin and Citric Acid
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Tsveta Sarafska, Stanislava Ivanova, Todor Dudev, Christo Tzachev, Vesselin Petrov, and Tony Spassov
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Ibuprofen ,cyclodextrin ,citric acid ,inclusion complex ,solubility ,dissolution rate ,Organic chemistry ,QD241-441 - Abstract
The ability of β-CD to form inclusion complexes with ibuprofen (IBU) and at the same time to make a two-phase system with citric acid was explored in the present study for achieving improved solubility and dissolution rate of IBU. Mechanical milling as well as mechanical milling combined with thermal annealing of the powder mixtures were applied as synthetic methods. Solubility and dissolution kinetics of the complexes were studied in compliance with European Pharmacopoeia (ICH Q4B). β-CD and citric acid (CA) molecules were shown to interact by both ball milling (BM), thermal annealing, as well as BM with subsequent annealing. Complexes were also formed by milling the three compounds (β-CD, CA and IBU) simultaneously, as well as by a consecutive first including IBU into β-CD and then binding the formed β-CD/IBU inclusion complex with CA. As a result, ternary β-CD/IBU/CA complex formed by initial incorporation of ibuprofen into β-CD, followed by successive formation of a two-phase mixture with CA, exhibited notably improved dissolution kinetics compared to the pure ibuprofen and slightly better compared to the binary β-CD/IBU system. Although the addition of CA to β-CD/IBU does not significantly increase the solubility rate of IBU, it must be considered that the amount of β-CD is significantly less in the ternary complex compared to the binary β-CD/IBU.
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- 2024
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14. A Comparison between Bulgarian Tanacetum parthenium Essential Oil from Two Different Locations
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Borislava Lechkova, Niko Benbassat, Diana Karcheva-Bahchevanska, Kalin Ivanov, Lyudmil Peychev, Zhivko Peychev, Stanislav Dyankov, Yoana Georgieva-Dimova, Krasimir Kraev, and Stanislava Ivanova
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Tanacetum parthenium ,feverfew ,essential oil ,GC/MS ,Organic chemistry ,QD241-441 - Abstract
Tanacetum parthenium L. (Asteraceae) is a perennial herbaceous plant with a long-standing historical use in traditional medicine. Recently Tanacetum parthenium L. essential oil has been associated with a promising potential for future applications in the pharmaceutical industry, in the cosmetics industry, and in agriculture. Investigations on the essential oil (EO) have indicated antimicrobial, antioxidant, and repellent activity. The present study aimed to evaluate the chemical composition of Bulgarian T. parthenium essential oil from two different regions, to compare the results to those reported previously in the literature, and to point out some of its future applications. The essential oils of the air-dried flowering aerial parts were obtained by hydrodistillation using a Clevenger-type apparatus. The chemical composition was evaluated using gas chromatography with mass spectrometry (GC-MS). It was established that the oxygenated monoterpenes were the predominant terpene class, followed by the monoterpene hydrocarbons. Significant qualitative and quantitative differences between both samples were revealed. Camphor (50.90%), camphene (16.12%), and bornyl acetate (6.05%) were the major constituents in the feverfew EO from the western Rhodope Mountains, while in the EO from the central Balkan mountains camphor (45.54%), trans-chrysanthenyl acetate (13.87%), and camphene (13.03%) were the most abundant components.
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- 2024
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15. Crithmum maritimum L.—Study on the Histochemical Localization of Essential Oil
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Velina Dzhoglova, Kalin Ivanov, Niko Benbassat, Yoana Georgieva-Dimova, Rayna Ardasheva, Diana Karcheva-Bahchevanska, and Stanislava Ivanova
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Apiaceae ,Crithmum maritimum L. ,secretory ducts ,essential oil ,GC-MS ,traditional medicine ,Botany ,QK1-989 - Abstract
Crithmum maritimum L. is a perennial halophyte plant that is a medicinal herb known by people from different cultures since ancient times. However, the therapeutic potential of this halophyte has not been completely investigated, and the scientific data on it are limited. The purpose of the present study was to estimate the chemical composition of the essential oil (EO) obtained from the aerial parts of Crithmum maritimum L. growing wild in Bulgaria, as well as the histolocalization of secretory structures for the synthesis and accumulation of volatile oils. The results obtained on the EO composition of Bulgarian Crithmum maritimum L. provide an opportunity to reveal potential future applications in various fields, such as medicine, pharmacy, agriculture, food, and the cosmetic industry. Gas chromatography with mass spectrometry was performed to assess the chemical profile of the isolated EO. The phenylpropanoid dillapiole was identified as the major compound in the EO, accounting for 34.09% of the total EO. Monoterpene hydrocarbons represented 62.07% of the total oil composition. γ-Terpinene, D-limonene, and β-pinene were the most abundant monoterpene hydrocarbons in the composition of the EO. In addition, histochemical localization of EO in the stem and leaves of Crithmum maritimum L. was carried out. The secretory structures were located in the cortical region of the stem and in the mesophyll tissues of the leaves in the form of secretory ducts. The performed histochemical analysis confirmed the lipophilic nature of the secretion from the duct cells. This is the first report related to the histolocalization and chemical composition of the EO from Bulgarian Crithmum maritimum L. Furthermore, our data indicate some potential possibilities for the evaluation of the therapeutic activity of the EO obtained from this plant species and outline its future applications as a therapeutic agent. Also, the EO from the studied halophyte plant has prominent potential to be used as a biopesticide, which is an environmentally friendly option compared to standard pesticides.
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- 2024
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16. Comparison between the Chemical Composition of Essential Oil from Commercial Products and Biocultivated Lavandula angustifolia Mill.
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Velislava Todorova, Kalin Ivanov, Yoana Georgieva, Diana Karcheva-Bahchevanska, and Stanislava Ivanova
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Analytical chemistry ,QD71-142 - Abstract
The main aim of this study was to assess the differences in the chemical composition of essential oil from biocultivated Lavandula angustifolia in the Thracian Lowland floristic region, Bulgaria, and commercially available products from Bulgarian markets. Following the analytical results conducted with gas chromatography-mass spectrometry, we have established some differences in the chemical composition of the tested samples. The essential oil of biocultivated lavender contained 35 compounds, which represent 94.13% of the total oil. Samples from commercial products contained 28–42 compounds that represent 93.03–98.69% of the total oil. All the examined samples were rich in monoterpene hydrocarbons (1.68–12.77%), oxygenated monoterpenes (70.42–87.96%), sesquiterpene hydrocarbons (4.03–13.78%), and oxygenated sesquiterpenes (0.14–0.76%). The dominant components in all examined samples were linalool (20.0–45.0%) and linalyl acetate (20.79–39.91%). All the examined commercial samples contained linalool and linalyl acetate as was described in the European Pharmacopoeia, but in one of the samples, the quality of linalyl acetate is lower than that recommended in the European Pharmacopoeia.
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- 2023
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17. Chemical Composition and Future Perspectives of Essential Oil Obtained from a Wild Population of Stachys germanica L. Distributed in the Balkan Mountains in Bulgaria
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Stanislava Ivanova, Stela Pashova, Stanislav Dyankov, Yoana Georgieva, Kalin Ivanov, Niko Benbassat, Nina Koleva, Maria Bozhkova, and Diana Karcheva-Bahchevanska
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Analytical chemistry ,QD71-142 - Abstract
Stachys germanica L. (Lamiaceae) is a plant associated with a rich history in the traditional medicine of Iran, Turkey, and Serbia. However, researchers have not fully investigated the pharmacological potential of the herb, and scientific data on this plant species are limited. The aim of the current study was to evaluate the chemical composition of the essential oil (EO) obtained from the aerial parts of S. germanica L. growing wild in Bulgaria and to perform a comparative analysis of the chemical composition of EOs obtained from the same plant species from other geographical regions. For the evaluation of the chemical profile of the isolated EO, gas chromatographic analysis with mass spectrometry was performed. The most abundant terpene class was oxygenated monoterpenes, which accounted for 59.30% of the total EO composition. The bicyclic monoterpene camphor, as a compound of this class, was identified as the major constituent in the EO, accounting for 52.96% of the total oil composition. The chemical profile of Bulgarian EO is quite different compared to that of EOs from other regions. It is the only one to contain more than 50% camphor. In addition, EO contains significant amounts of the diterpene geranyl p-cymene (10.49%). This is the first study describing the chemical composition of EO from Bulgarian Stachys germanica L., and our results reveal some future perspectives for the evaluation of the biological activity of EO from the studied plant species as a new therapeutic agent or natural remedy targeting different medical conditions. The EO has a promising potential to be used as a biopesticide and repellent as well, an environmentally friendly and safer alternative to standard pesticides.
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- 2023
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18. A Study of the Chemical Composition, Antioxidant Potential, and Acute Toxicity of Bulgarian Tanacetum vulgare L. Essential Oil
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Diana Karcheva-Bahchevanska, Niko Benbassat, Yoana Georgieva, Borislava Lechkova, Stanislava Ivanova, Kalin Ivanov, Velislava Todorova, Lyudmil Peychev, Zhivko Peychev, and Petko Denev
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Tanacetum vulgare L. ,essential oil composition ,GC/MS ,antioxidant activity ,in vivo acute toxicity ,Organic chemistry ,QD241-441 - Abstract
Common tansy (Tanacetum vulgare L.) is a plant with medicinal properties that has traditionally been used in folk medicine for its anthelmintic, antispasmodic, and choleretic effects, for the treatment of diarrhea and digestive problems, and externally, as an insecticide in veterinary practices. In the current study, we investigated, for the first time, the chemical profile and antioxidant activity of essential oil from a wild population of T. vulgare L. growing in Bulgaria. Common tansy essential oil (EO), which is rich in bicyclic monoterpenes, was obtained using hydrodistillation and characterized by using gas chromatography–mass spectrometry (GC-MS). Thirty-seven compounds were identified in Bulgarian tansy EO. Among the major constituents were oxygenated monoterpenes, including compounds such as camphor (25.24%), trans-chrysantenyl acetate (18.35%), cis-verbenol (10.58%), thujone (6.06%), eucaliptol (5.99%), and α-campholenal (5.98%). The analysis results identified the essential oil from T. vulgare L. grown in the western Rhodope Mountains of Bulgaria as the camphor chemotype. Furthermore, its antioxidant activity was analyzed using the oxygen radical absorbance capacity (ORAC) method and was found to be 605.4 ± 49.3 µmol TE/mL. The essential oil was also tested for single-dose acute toxicity on Wistar rats and was found to be non-toxic by oral administration. The mean lethal dose by intraperitoneal administration was LD50 i.p. = 14.9 g/kg body weight. The results of the conducted study can serve as a basis for the evaluation and subsequent exploration of other pharmacotherapeutic effects of the essential oil obtained from the inflorescences of the Bulgarian species T. vulgare L.
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- 2023
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19. A Study of the Chemical Composition, Acute and Subacute Toxicity of Bulgarian Tanacetum parthenium Essential Oil
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Borislava Lechkova, Diana Karcheva-Bahchevanska, Kalin Ivanov, Velislava Todorova, Niko Benbassat, Nadya Penkova, Pepa Atanassova, Lyudmil Peychev, Petar Hrischev, Zhivko Peychev, Dimitar Terziev, and Stanislava Ivanova
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Tanacetum parthenium ,essential oil ,feverfew ,acute and subacute toxicity ,hematological ,serum biochemical ,Organic chemistry ,QD241-441 - Abstract
Background: Tanacetum parthenium (L.) Sch.Bip. (T. parthenium) is an aromatic perennial plant belonging to the Asteraceae family, also known as feverfew. It is widely distributed in various regions of Europe and other parts of the world. The plant has a rich background in the traditional medicine of many nations and has been used as a remedy for fever, pain, inflammation, asthma, rheumatism, menstrual disorders, etc. Methods: GC–MS analysis was conducted to determine the chemical composition of the isolated essential oil (EO). Using the method proposed by Litchfield and Wilcoxon, the average lethal dose (LD50) of the EO on Wistar rats was determined for two routes of administration: oral (p.o.) and intraperitoneal (i.p.). The subacute toxicity of the EO was also tested by oral administration of a daily dose of 1.0 g/kg body weight (BW) for 28 days. The toxicity of the EO was evaluated by observing and evaluating changes in behavior, body weight, basic hematological and serum biochemical parameters, and histopathological changes of the internal organs. Results: Thirty-seven volatile organic compounds representing 94.58% of the total oil composition were tentatively detected in the obtained T. parthenium EO. The dominant compounds were camphor (45.47%), trans-chrisantenyl acetate (21.65%), camphene (9.48%), and cis-isogeraniol (5.42%). The results showed that the EO was not toxic when administered in acute oral doses. The acute mean lethal dose for intraperitoneal administration was LD50 i.p. = 2.13 g/kg BW. In the subacute study involving administration of an oral dose of EO for 28 days, there were a number of changes in the hematological and serum biochemical parameters of the blood compared with the control group of animals. However, no symptoms of toxicity, changes in the body weight of the rats, death, or pathological changes in the histological indicators of the examined organs—brain, heart, stomach, liver, spleen and kidney—were found. Extrapolating the results obtained from the rat experiments, we can state that the EO is safe for use in doses below 1 g/kgBW for a period not exceeding one month.
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- 2023
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20. Echinophora tenuifolia subsp. sibthorpiana—Study of the Histochemical Localization of Essential Oil
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Stanislava Ivanova, Stanislav Dyankov, Diana Karcheva-Bahchevanska, Velislava Todorova, Yoana Georgieva, Niko Benbassat, and Kalin Ivanov
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Echinophora ,Apiaceae ,Echinophora tenuifolia subsp. sibthorpiana ,Echinophora platyloba ,Echinophora spinosa ,folk medicine ,Organic chemistry ,QD241-441 - Abstract
Background: Echinophora tenuifolia L. subsp. sibthorpiana is a perennial, aromatic plant used in traditional folk medicine and cuisine of the Mediterranean and the Middle East. However, scholars have not fully studied the pharmacological potential of the herb, and the scientific data on this plant species are limited. This study aimed to evaluate the chemical composition of the essential oil (EO) obtained from the aerial parts of E. tenuifolia subsp. sibthorpiana growing wild in Bulgaria and to perform histochemical analysis. Methods: A microscopic histochemical analysis and gas chromatography with mass spectrometry were performed. Results: The histochemical analysis confirmed the presence of terpenes in the stem and leaf of E. tenuifolia subsp. sibthorpiana. The phenylpropanoid methyleugenol was identified as the main compound in the EO, representing 48.13% of the total oil composition. There were also found considerable amounts of monoterpene hydrocarbons, representing 41.68% of the total EO. Alpha-phellandrene, o-cymene, and β-phellandrene were the most abundant monoterpene hydrocarbons. Conclusion: This is the first histochemical analysis performed on E. tenuifolia subsp. sibthorpiana. This is the first report of the EO composition from Bulgarian E. tenuifolia subsp. sibthorpiana, and our results indicate some future possibilities for evaluating of the biological activity of the EO of E. tenuifolia subsp. sibthorpiana and highlight the potential future use of the EO of this plant species. E. tenuifolia L. subsp. sibthorpiana EO possesses a good potential for use as a biopesticide and repellent an environmentally friendly alternative of synthetic pesticides.
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- 2023
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21. Chemical Composition and Histochemical Localization of Essential Oil from Wild and Cultivated Rhaponticum carthamoides Roots and Rhizomes
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Velislava Todorova, Stanislava Ivanova, Yoana Georgieva, Vanya Nalbantova, Diana Karcheva-Bahchevanska, Niko Benbassat, Martina S. Savova, Milen I. Georgiev, and Kalin Ivanov
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Rhaponticum carthamoides (Willd.) Iljin ,Maral root ,secretory structures ,GC-MS ,Botany ,QK1-989 - Abstract
Rhaponticum carthamoides (Willd.) Iljin is not only a source of phytosteroids and flavonoids, but is also source of essential oil (EO). This study evaluated the volatile metabolic constituents and histochemical localization of root and rhizome essential oils (EOs) from R. carthamoides populations wild-grown in Russia and cultivated in Bulgaria. The performed histochemical analysis confirmed the presence of lipophilic substances in the secretory ducts of the examined roots and rhizomes. Both EOs were obtained by hydrodistillation and further analyzed by gas chromatography with mass detection. The results showed differences between the chemical compositions of both EOs. Forty-six components were tentatively identified in R. carthamoides oil from the wild population, with β-selinene (4.77%), estragole (6.32%), D-carvone (6.37%), cyperene (8.78%), and ledene oxide (11.52%) being the major constituents. In the EO isolated from cultivated R. carthamoides, twenty-three compounds were tentatively identified, with humulene (7.68%), β-elemene (10.76%), humulene-1,2-epoxide (11.55%), ledene oxide (13.50%), and δ-elemene (19.08%) predominating. This is the first report describing the histolocalization and chemical profile of EO from R. carthamoides cultivated in Bulgaria. Further research on the cultivation of R. carthamoides in Bulgaria would affect the relationship between its chemical composition and pharmacological effects.
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- 2022
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22. Prognostic importance of endothelin-1 and endothelin receptor: a plasma levels in the early perimetric stage of primary open-angle glaucoma
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Bilyana Mihaylova, Anton Vassilev, Galina Dimitrova, Charita Rankova-Yotova, Iva Petkova, Stanislava Ivanova, and Alexander Oscar
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Glaucoma ,endothelin-1 ,endothelin receptor-A ,plasma levels ,retinal nerve fibre layer ,regression analysis ,Biotechnology ,TP248.13-248.65 - Abstract
An increasing amount of data suggests a role of the eye vascular system and oxidative stress in glaucoma pathogenesis. Reports have suggested endothelin-1 (ET-1) and its receptor (ETR-A) as possible glaucoma biomarkers. This study explored the diagnostic and prognostic abilities of ET-1 and ETR-A plasma concentrations in primary open angle glaucoma (POAG). Seventy-five participants were divided into three groups: controls, early and advanced POAG stage, graded by a perimetric visual field test. All of them underwent a standard ophthalmological examination including optical coherence tomography. The statistical analysis showed a significant difference between the ET-1 values in the controls (4.88 ± 1.75 pg/mL) and the glaucoma patients, but lack of statistical significance in the glaucoma severity (early POAG: 6.33 ± 2.38 pg/mL and advanced POAG: 6.34 ± 1.56 pg/mL). The mean ETR-A values were significantly different between the three groups (controls 1209.28 ± 314.48 pg/mL, early POAG: 673.44 ± 283.02 pg/mL and advanced POAG: 992.28 ± 264.22 pg/mL). Two mathematical models were developed concerning the two perimetric indices (MD/PSD) and ETR-A in the early glaucoma group. ETR-A showed a very high diagnostic accuracy. Only ETR-A had significant diagnostic ability for advanced glaucoma after the comparison between the two glaucoma groups. Every 1 pg/mL increase in the ET-1 plasma concentration increased the possibility for early glaucoma changes by 2.124 times, whereas every 1 pg/mL increase in the ETR-A level decreased this possibility by 1%. Our results indicate that ET-1 and ETR-A could be two very good diagnostic parameters for early POAG changes.
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- 2018
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23. Polysaccharides and Their Derivatives as Potential Antiviral Molecules
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Hadrien Claus-Desbonnet, Elsa Nikly, Vanya Nalbantova, Diana Karcheva-Bahchevanska, Stanislava Ivanova, Guillaume Pierre, Niko Benbassat, Plamen Katsarov, Philippe Michaud, Paolina Lukova, and Cédric Delattre
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polysaccharides ,antiviral activities ,virus and coronavirus ,severe acute respiratory syndrome ,SARS-CoV ,replication inhibition ,Microbiology ,QR1-502 - Abstract
In the current context of the COVID-19 pandemic, it appears that our scientific resources and the medical community are not sufficiently developed to combat rapid viral spread all over the world. A number of viruses causing epidemics have already disseminated across the world in the last few years, such as the dengue or chinkungunya virus, the Ebola virus, and other coronavirus families such as Middle East respiratory syndrome (MERS-CoV) and severe acute respiratory syndrome (SARS-CoV). The outbreaks of these infectious diseases have demonstrated the difficulty of treating an epidemic before the creation of vaccine. Different antiviral drugs already exist. However, several of them cause side effects or have lost their efficiency because of virus mutations. It is essential to develop new antiviral strategies, but ones that rely on more natural compounds to decrease the secondary effects. Polysaccharides, which have come to be known in recent years for their medicinal properties, including antiviral activities, are an excellent alternative. They are essential for the metabolism of plants, microorganisms, and animals, and are directly extractible. Polysaccharides have attracted more and more attention due to their therapeutic properties, low toxicity, and availability, and seem to be attractive candidates as antiviral drugs of tomorrow.
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- 2022
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24. Higenamine in Plants as a Source of Unintentional Doping
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Vanya Rangelov Kozhuharov, Kalin Ivanov, and Stanislava Ivanova
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higenamine in plants ,Nelumbo nucifera ,Tinospora crispa ,Nandina domestica ,Gnetum parvifolium ,Asarum siebodii ,Botany ,QK1-989 - Abstract
Background: Higenamine is a β2 agonist of plant origin. The compound has been included in WADA’s prohibited list since 2017. Higenamine may be detected in different plants and many food supplements of natural origin. Methods: Our literature search was conducted through PubMed, Science Direct, Google Scholar, and Web of Science studies investigating the presence of higenamine in plants that are used in traditional folk medicine or included in food supplements. Our study aimed to assess the risk of adverse analytical findings caused by higenamine-containing plants. Results: Based on our literature search, Nelumbo nucifera, Tinospora crispa, Nandina domestica, Gnetum parvifolium, Asarum siebodii,Asarum heterotropoides, Aconitum carmichaelii, and Aristolochia brasiliensis are higenamine-containing plants. Based on data from Eastern folk medicine, these plants can provide numerous health benefits. Professional athletes likely ingest these plants without knowing that they contain higenamine; these herbs are used in treatments for different conditions and various foods/food supplements in addition to folk medicine. Conclusion: Athletes and their teams must be aware of the issues associated with the use of plant-based products. They should avoid consuming higenamine-containing plants during and outside of competition periods.
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- 2022
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25. Plant-Based Diet as a Strategy for Weight Control
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Stanislava Ivanova, Cédric Delattre, Diana Karcheva-Bahchevanska, Niko Benbasat, Vanya Nalbantova, and Kalin Ivanov
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obesity ,globesity ,vegan ,plant-based diet ,vegetarian ,weight control ,Chemical technology ,TP1-1185 - Abstract
According to the World Health Organization, obesity has nearly tripled since the 1970s. Obesity and overweight are major risk factors for cardiovascular diseases, diabetes, inflammatory-mediated diseases, and other serious medical conditions. Moreover, recent data suggest that obesity, overweight, diabetes, and cardiovascular diseases are risk factors for COVID-19-related mortality. Different strategies for weight control have been introduced over the last two decades. Unfortunately, these strategies have shown little effect. At the same time, many studies show that plants might be the key to a successful strategy for weight control. Following the PRISMA guidelines for conducting systematic reviews, a search was conducted in PubMed, Web of Science, Scopus, and Embase using the following keywords: obesity, globesity, vegan, plant-based diet, etc. Our results show that vegan diets are associated with improved gut microbiota symbiosis, increased insulin sensitivity, activation of peroxisome proliferator-activated receptors, and over-expression of mitochondrial uncoupling proteins. The key features of this diet are reduced calorie density and reduced cholesterol intake. The combination of these two factors is the essence of the efficiency of this approach to weight control. Our data suggest that plant-based/vegan diets might play a significant role in future strategies for reducing body weight.
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- 2021
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26. Comparison between the Biological Active Compounds in Plants with Adaptogenic Properties (Rhaponticum carthamoides, Lepidium meyenii, Eleutherococcus senticosus and Panax ginseng)
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Velislava Todorova, Kalin Ivanov, and Stanislava Ivanova
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adaptogen ,adaptogens ,plant adaptogens ,Rhaponticum carthamoides ,Leuzea ,ecdysterone ,Botany ,QK1-989 - Abstract
Background: In the 1960s, research into plant adaptogens began. Plants with adaptogenic properties have rich phytochemical compositions and have been used by humanity since ancient times. However, it is not still clear whether the adaptogenic properties are because of specific compounds or because of the whole plant extracts. The aim of this review is to compare the bioactive compounds in the different parts of these plants. Methods: The search strategy was based on studies related to the isolation of bioactive compounds from Rhaponticum carthamoides, Lepidium meyenii, Eleutherococcus senticosus, and Panax ginseng. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Results: This review includes data from 259 articles. The phytochemicals isolated from Rhaponticum carthamoides, Lepidium meyenii, Eleutherococcus senticosus, and Panax ginseng were described and classified in several categories. Conclusions: Plant species have always played an important role in drug discovery because their effectiveness is based on the hundreds of years of experience with folk medicine in different nations. In our view, there is great potential in the near future for some of the phytochemicals found in these plants species to become pharmaceutical agents.
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- 2021
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27. Plasma endothelin-1 and endothelin-A receptor concentrations in patients with primary open-angle glaucoma
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Bilyana Mihaylova, Iva Petkova, Charita Rankova-Yotova, Galina Dimitrova, Ivan Tanev, Stanislava Ivanova, Adelina Tsakova, and Dobrin Svinarov
- Subjects
Glaucoma ,endothelin-1 ,endothelin-A receptor ,plasma levels ,retinal nerve fibre layer ,optical coherence tomography ,Biotechnology ,TP248.13-248.65 - Abstract
Endothelin-1 (ET-1) is a potent vasoconstrictor and is considered to have a key role in the regulation of ocular perfusion and glaucoma pathogenesis. High ET-1 and ETA-receptor levels are reported in patients with primary open-angle glaucoma (POAG). We compared the mean plasma ET-1 and ETA-receptor concentration of controls and patients with early and advanced POAG stage, and assessed the correlation with the retinal nerve fibre layer (RNFL) thickness. The study included a total of 75 participants, aged 45–83 years: 25 (controls), 22 (early glaucoma) and 28 (advanced glaucoma). The plasma concentration of ET-1 and ETA-receptor was determined by enzyme-linked immunosorbent assay. The RNFL thickness was evaluated with spectral-domain optical coherence tomography. The mean ET-1 concentration was lower in the control group (4.88 ± 1.75 pg/mL) than in the early and advanced POAG group (6.33 ± 2.38 and 6.34 ± 1.56 pg/mL). Statistically significant difference was found between the mean ET-1 concentrations in controls and glaucoma patients (p = 0.029 – early glaucoma, p = 0.018 – advanced glaucoma), and no significant difference was observed between the two POAG groups (p = 0.998). The mean ETA-receptor concentration was highest in the control group (1209.28 ± 314.48 pg/mL) and the differences between the three groups were significant. Significant relationship was found only between ET-1 and RNFL. This study demonstrated the role of ET-1 in glaucoma pathogenesis based on the observed significant high ET-1 and ETA-receptor plasma levels in POAG patients. A new therapeutical approach needs to be considered in some patients.
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- 2017
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28. Fake PLC in the Cloud, We Thought the Attackers Believed that: How ICS Honeypot Deception Gets Impacted by Cloud Deployments?
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Stanislava Ivanova and Naghmeh Moradpoor
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- 2023
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29. Attitudes toward robots : fiction or reality?
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Naneva, Stanislava Ivanova, Webb, Thomas L., and Prescott, Tony J.
- Abstract
One challenge to understanding how people think and feel about robots is the wide variety of robotic systems and the general public's lack of direct contact with them, which leaves open the question of whether people's attitudes toward robots are shaped by exposure to real robotic systems or not. This thesis presents evidence that people not only internally represent the concept of robots in varied ways but also that such representations may account for some of the reported variability in people's attitudes toward robots. Chapter 2 presents a systematic review that demonstrated said variability by quantifying people's attitudes toward social robots and highlighted a number of factors that have arguably not been sufficiently explored in the literature. Namely, the influence of people's individual representation of robots and the potential impact of fictional and non-fictional depictions of robots on people's attitudes. Chapter 3 explored both of these factors by presenting a semantic network reflecting the social representation of robots that supported the diversity of individuals' representations and provided insights into the stable structure of the social representation which was divided into five distinct modules of meaning. These modules were further interrogated in the same chapter via the thematic analysis of semi-structured interviews which demonstrated both the role of fiction in people's individual representation of robots as well as the impact of said representations on people's attitudes. In order to investigate the impact of fictional robots on people's attitudes, three pilot studies that manipulated the perceived fictional status of identical robots through indirect contact were conducted and reported in Chapter 4. The methodology was then implemented in an experimental study that tested whether the perception of the fictionality of the robots had an effect on participants' attitudes (reported in Chapter 5). Findings showed that when robots are perceived as non-fictional, participants reported more positive explicit (but not implicit) attitudes toward those specific robots and toward robots in general than when the same robots were perceived as fictional. Chapter 5 also describes the findings of a second experimental study that primed participants with images of either fictional or non-fictional representations of robots. Findings supported the preference for non-fictional robots found in the previous study but in this case, there was a change in participants implicit, rather than explicit, attitudes. The implications of these findings are discussed in Chapter 6.
- Published
- 2021
30. Inflorescence Essential Oil Composition of Tanacetum macrophyllum (Waldst. & Kit.) Schultz Bip. Growing Wild in Bulgaria
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Yoana Georgieva, Niko Benbassat, Diana Karcheva-Bahchevanska, Paolina Lukova, Vanya Nalbantova, Kalin Ivanov, Velislava Todorova, and Stanislava Ivanova
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Organic Chemistry ,Biochemistry ,Analytical Chemistry - Published
- 2023
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31. IMPACT OF COVID-19 ON IT EMPLOYEES’ JOB PERFORMANCE – A COMPARATIVE ANALYSIS
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Stanislava Ivanova and Irina Yanchovska
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General Medicine - Abstract
The research paper examines how the job performance of IT employees changed during the pandemic when remote work was the predominant mode of operation for more than a year. The study also investigates how the different aspects of job performance have evolved during the research. Quantitative data was collected through a longitudinal survey conducted in 2019 and then repeated in 2021. In the first phase, the sample consisted of 126 international respondents working in over 25 different IT companies, while in the second phase, 149 respondents from over 60 different organizations were covered. The data for the study has been analysed by using one-dimensional mean value comparison, correlation, and regression analysis. In the first phase of the survey conducted before the pandemic, quality of work, effectiveness, and value-added performance have the strongest influence on job performance, at the same time employees’ productivity and proactiveness did not show a direct impact on their overall performance. In the second phase of the study conducted in the summer of 2021, the results show that employees’ perception of their value-added performance to the organization no longer impacts their overall performance. Additionally, during the pandemic, a downward trend was observed in all the elements of job performance, with the most significant decrease in employees’ overall performance, quality of work, and effectiveness. The results of the study can be compelling to different levels of the organisations, as good job performance of employees is significant for the performance results of teams, business units, and organisations. Understanding employees’ job performance, its elements, and how it changes over time, especially during the pandemic, can help organisations thrive and develop a more productive workforce.
- Published
- 2022
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32. Anti-Adipogenic Activity of Rhaponticum carthamoides and Its Secondary Metabolites
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Georgiev, Velislava Todorova, Martina S. Savova, Stanislava Ivanova, Kalin Ivanov, and Milen I.
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Rhaponticum carthamoides (Willd.) Iljin ,20-hydroxyecdysone ,ponasterone A ,turkesterone ,high-performance thin layer chromatography (HPTLC) ,obesity ,adipocytes ,adipogenesis ,adipolysis - Abstract
Besides their common use as an adaptogen, Rhaponticum carthamoides (Willd.) Iljin. rhizome and its root extract (RCE) are also reported to beneficially affect lipid metabolism. The main characteristic secondary metabolites of RCE are phytoecdysteroids. In order to determine an RCE’s phytoecdysteroid profile, a novel, sensitive, and robust high-performance thin-layer chromatography (HPTLC) method was developed and validated. Moreover, a comparative analysis was conducted to investigate the effects of RCE and its secondary metabolites on adipogenesis and adipolysis. The evaluation of the anti-adipogenic and lipolytic effects was performed using human Simpson–Golabi–Behmel syndrome cells, where lipid staining and measurement of released glycerol and free fatty acids were employed. The HPTLC method confirmed the presence of 20-hydroxyecdysone (20E), ponasterone A (PA), and turkesterone (TU) in RCE. The observed results revealed that RCE, 20E, and TU significantly reduced lipid accumulation in human adipocytes, demonstrating their anti-adipogenic activity. Moreover, RCE and 20E were found to effectively stimulate basal lipolysis. However, no significant effects were observed with PA and TU applications. Based on our findings, RCE and 20E affect both lipogenesis and lipolysis, while TU only restrains adipogenesis. These results are fundamental for further investigations.
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- 2023
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33. Dietary Supplements as Source of Unintentional Doping
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Vanya Rangelov Kozhuharov, Kalin Ivanov, and Stanislava Ivanova
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Doping in Sports ,General Immunology and Microbiology ,Athletes ,Dietary Supplements ,Humans ,General Medicine ,General Biochemistry, Genetics and Molecular Biology ,Sports - Abstract
Background. The substances used in sport could be divided into two major groups: those banned by the World Anti-Doping Agency and those which are not. The prohibited list is extremely detailed and includes a wide variety of both medicinal and nonmedicinal substances. Professional athletes are exposed to intense physical overload every day. They follow a relevant food regime and take specific dietary supplements, which is essential for the better recovery between trainings and competitions. However, the use of “nonprohibited” dietary supplements (DS) is not always completely safe. One of the risks associated with the use of dietary supplements is the risk of unintended doping—originating from contaminated products. The presence of undeclared compounds in the composition of DS is a serious concern. The aim of this study is to evaluate the risk of unintentional doping. Materials and Methods. Literature search was done through PubMed, Science Direct, Google Scholar, and Web of Science. Studies investigating the presence of undeclared compounds, in dietary supplements, banned by WADA met the inclusion criteria. The last search was conducted in June 2021. The present review is based on a total of 50 studies, which investigated the presence of undeclared compounds in DS. Results. The total number of analyzed DS is 3132, 875 of which were found to contain undeclared substances. Most frequently found undeclared substances are sibutramine and anabolic-androgenic steroids. Conclusion. More than 28% of the analyzed dietary supplements pose a potential risk of unintentional doping. Athletes and their teams need to be aware of the issues associated with the use of DS. They should take great care before inclusion of DS in the supplementation regime.
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- 2022
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34. A randomized pharmacokinetic/pharmacodynamic study comparing the bioequivalence of potential biosimilar candidate P044 with reference medicine in healthy volunteers
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Ekaterina Raykova, Stanislava Ivanova, Mohammad Farmahini Farahani, and Morteza Azhdarzadeh
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Pharmacology ,medicine.medical_specialty ,Cross-Over Studies ,business.industry ,Clinical Biochemistry ,Cmax ,Biosimilar ,Bioequivalence ,Crossover study ,Healthy Volunteers ,Confidence interval ,Double-Blind Method ,Therapeutic Equivalency ,Pharmacokinetics ,Internal medicine ,Pharmacodynamics ,Drug Discovery ,medicine ,Humans ,Female ,Adverse effect ,business ,Biosimilar Pharmaceuticals - Abstract
BACKGROUND P044 is a proposed biosimilar candidate of Teriparatide for reference medicine, Forsteo®. This study was designed to evaluate the Pharmacokinetic/Pharmacodynamic (PK/PD) bioequivalence between P044 and Forsteo®. METHODS In this randomized, open-label, single-dose, crossover study, 66 healthy female subjects were randomized to receive P044 and Forsteo®. The primary PK endpoints of the study were the area under the concentration versus time from zero to infinity (AUC0-inf) and maximum plasma concentration (Cmax). Secondary endpoints included area under the concentration versus time from zero to the last quantifiable concentration (AUC0-last) and Cmax for PD parameter, additional PK parameters and safety. RESULTS Sixty-six subjects were enrolled in the study and baseline demographics were similar between the two treatments. The two treatments presented similar PK/PD parameters and the 90% confidence interval for primary and secondary endpoints were within the bioequivalence acceptance range (80.00-125.00%) for all parameters. None of the subjects experienced serious adverse event, and all of the reported adverse events were mild and similar between two treatments. CONCLUSIONS This study demonstrated the PK/PD similarity of P044 to reference medicine, Forsteo® and safety profiles were comparable between treatments. TRIAL REGISTRATION EudraCT Number: 2019-004477-82.
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- 2021
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35. Regulatory Requirements for Food Supplements in the European Union and Bulgaria
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Vasil G. Madzharov, Radiana Staynova, Kalin Ivanov, Violeta Getova, Stanislava Ivanova, Anna Mihaylova, Elina Petkova-Gueorguieva, Stanislav Gueorguiev, and Ilko Getov
- Subjects
0301 basic medicine ,safety ,Economic growth ,Food Safety ,Parliament ,media_common.quotation_subject ,Scopus ,MEDLINE ,lcsh:Medicine ,Legislation ,legislation ,03 medical and health sciences ,0302 clinical medicine ,media_common.cataloged_instance ,Humans ,Bulgarian ,Quality (business) ,European Union ,European union ,quality control ,Bulgaria ,media_common ,lcsh:R ,Legislature ,health ,General Medicine ,Legislation, Food ,language.human_language ,food supplements ,030104 developmental biology ,Dietary Supplements ,language ,030211 gastroenterology & hepatology - Abstract
Data provided by the European Commission show that public expenditures for food supplements have been constantly increasing over the last decade. The aim of the present study was to analyze the major food supplements regulations in the European Union and in Bulgaria. Relevant publications were searched and found in MEDLINE/PubMed, Scopus Database, Web of Knowledge, and in Internet-based search with predefined keywords. Numerous authors support the opinion that there is a real risk that low quality products may be distributed in countries with poor production control. Bulgarian national legislation have 6 regulations with different legal force for provision of healthy and safe food supplements on the market. Currently, the European Community is concerned about food products, including FS, launched on the market because the citizens require reliable protection of their health. This concern provoked the European Parliament and the Council to undertake a number of legislative initiatives in the field of production and control of food products. It is necessary to set more precise quality and safety criteria in future strategies associated with those products.
- Published
- 2019
36. Plant Adaptogens—History and Future Perspectives
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Vanya Nalbantova, Diana Karcheva-Bahchevanska, Cédric Delattre, Velislava Todorova, Kalin Ivanov, Stanislava Ivanova, Institut Pascal (IP), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national polytechnique Clermont Auvergne (INP Clermont Auvergne), and Université Clermont Auvergne (UCA)-Université Clermont Auvergne (UCA)
- Subjects
Adult ,Male ,Schisandra chinensis ,Adolescent ,Review ,History, 21st Century ,Young Adult ,Ginseng ,Rhaponticum carthamoides ,Stress, Physiological ,Animals ,Humans ,[SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering ,TX341-641 ,Panax ginseng ,Cognitive impairment ,Eleuterococcus senticosus ,High potential ,Nutrition and Dietetics ,biology ,Traditional medicine ,Plant Extracts ,Immune protection ,Nutrition. Foods and food supply ,Eleutherococcus senticosus ,food and beverages ,History, 20th Century ,Middle Aged ,biology.organism_classification ,Adaptation, Physiological ,Rhodiola rosea ,plant adaptogens ,Female ,Phytotherapy ,Food Science - Abstract
Adaptogens are synthetic compounds (bromantane, levamisole, aphobazole, bemethyl, etc.) or plant extracts that have the ability to enhance the body’s stability against physical loads without increasing oxygen consumption. Extracts from Panax ginseng, Eleutherococcus senticosus, Rhaponticum carthamoides, Rhodiola rosea, and Schisandra chinensis are considered to be naturally occurring adaptogens and, in particular, plant adaptogens. The aim of this study is to evaluate the use of plant adaptogens in the past and now, as well as to outline the prospects of their future applications. The use of natural adaptogens by humans has a rich history—they are used in recovery from illness, physical weakness, memory impairment, and other conditions. About 50 years ago, plant adaptogens were first used in professional sports due to their high potential to increase the body’s resistance to stress and to improve physical endurance. Although now many people take plant adaptogens, the clinical trials on human are limited. The data from the meta-analysis showed that plant adaptogens could provide a number of benefits in the treatment of chronic fatigue, cognitive impairment, and immune protection. In the future, there is great potential to register medicinal products that contain plant adaptogens for therapeutic purposes.
- Published
- 2021
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37. High-Performance Thin-Layer Chromatography (HPTLC) Method for Identification of Meloxicam and Piroxicam
- Author
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Stanislava Ivanova, Velislava Todorova, Stanislav Dyankov, and Kalin Ivanov
- Subjects
Process Chemistry and Technology ,Chemical Engineering (miscellaneous) ,Bioengineering ,HPTLC ,high-performance thin-layer chromatography ,TLC ,thin-layer chromatography ,NSAIDs ,meloxicam ,piroxicam - Abstract
Background: High-performance thin-layer chromatography (HPTLC) is an advantageous, modern analytical technique based on the principles of thin-layer chromatography (TLC), which provides essential benefits, such as improved sample application, better and faster separation, and less mobile phase usage. The aim of this work was to develop a simple and rapid HPTLC method that could be used for the identification of meloxicam and piroxicam. Methods: HPTLC. The analysis was carried out using silica gel 60 F254 glass TLC plates and as the mobile phase: hexane: ethyl acetate: glacial acetic acid, in a ratio of 65:30:5 v/v/v. For the standard solution preparation, ethanol was used. Front: 60 mm. Detection was performed at 366 nm. Results: The Rf value for meloxicam was 0.81 and the Rf value for piroxicam was 0.57. The proposed method can be used in the detection of the analyzed compounds in very low concentrations. It was established that the detection limit of meloxicam was 0.04 μg per band and that of piroxicam was 0.05 μg per band. It was also established that the quantitation limit of meloxicam was 0.12 μg per band and that of piroxicam was 0.15 μg per band. Conclusions: The proposed method is simple, sensitive, stable, cost effective, and eco-friendly. It could be used in research or for routine quality control purposes.
- Published
- 2022
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38. Methods To Enhance The Metabolic Stability Of Peptide Drugs
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Stanislava Ivanova, Silvia Mihaylova, and Antoaneta Tsvetkova
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chemistry.chemical_classification ,medicine.diagnostic_test ,Proteolysis ,Peptide ,Biological membrane ,Metabolism ,Small molecule ,Bioavailability ,chemistry.chemical_compound ,chemistry ,Pharmacokinetics ,Biochemistry ,Peptide synthesis ,medicine - Abstract
Therapeutic peptides have high selectivity, efficacy, and low toxicity. These characteristics, combined with advances in solid-phase peptide synthesis and purification methods, have led to the widespread use of peptide-based drugs. Limitations in the research and development of peptide drugs are related to their short plasma half-life, rapid metabolism, proteolytic degradation and poor penetration through biological membranes. This mini-review examines the advantages of peptide drugs over small molecule drugs and biotechnological proteins, as well as various chemical methods for peptide modifications to increase the metabolic stability, bioavailability and pharmacokinetic properties of peptides.
- Published
- 2021
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39. Presence of undeclared caffeine in weight loss food supplements
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Kalin Ivanov, Penka Petleshkova, Stanislava Ivanova, and Anna Mihaylova
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Drug ,media_common.quotation_subject ,Dietary supplement ,03 medical and health sciences ,chemistry.chemical_compound ,0404 agricultural biotechnology ,0302 clinical medicine ,food ,Weight loss ,Yerba-mate ,medicine ,Health risk ,media_common ,Traditional medicine ,Health consequences ,business.industry ,030229 sport sciences ,04 agricultural and veterinary sciences ,medicine.disease ,040401 food science ,Obesity ,food.food ,chemistry ,medicine.symptom ,Caffeine ,business - Abstract
Recent studies claim that weight loss supplements often contain pharmacoactive ingredients or undeclared drug substances with a potential health risk. This study is focused on food supplements in the category “weight loss” in which label caffeine was not declared. Analysed samples were purchased from dietary supplement stores, pharmacies and internet. In the screening were included only food supplements witch do not contain caffeine or herbal extracts which contain caffeine like guarana, kola nut, yerba mate etc. 30 samples were analysed by HPLC/UV detection. We found undeclared caffeine in 5 of the analysed samples. The presence of undeclared caffeine in food supplements for weight loss could lead to serious health consequences especially for consumers with cardiovascular disea
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- 2019
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40. Undeclared furosemide in food supplements
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Stanislava Ivanova and Kalin Ivanov
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Drug ,Anabolism ,business.industry ,media_common.quotation_subject ,010401 analytical chemistry ,Dietary supplement ,Furosemide ,04 agricultural and veterinary sciences ,040401 food science ,01 natural sciences ,High-performance liquid chromatography ,0104 chemical sciences ,0404 agricultural biotechnology ,medicine ,Food science ,Health risk ,Ephedrine ,business ,media_common ,Sibutramine ,medicine.drug - Abstract
Recent studies claim that dietary supplements could contain pharmaco-active ingredients or undeclared drug substances with a potential health risk. Most often these products are contaminated with anabolic steroids, ephedrine, sibutramine, diuretics and others. The intake of a contaminated dietary supplement could lead to serious health consequences (the pharmacological effect of the substances, side effects, drug interactions and many others) or other negative consequences like failure of a doping test (for professional athletes). We have performed HPLC screening for furosemide. Measurements were performed at 228 nm at a flow rate 0,8 ml/min. The mobile phase was composed of methanol and water in a ratio 80: 20 (v/v). The pH of the mobile phase was 3,3 adjusted with Phosphorous acid. Chromatographic column - Microsorb-MV 100-5 C18 150 × 4.6 mm. We have analysed 30 food supplements in the category”prostate health”. We have found undeclared furosemide in 10% of the samples.
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- 2019
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41. Yohimbine intake-health risks - Correlation between side effects and the quality of the yohimbine bark: A UHPLC/MS, GC/MS screening
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Kalin Ivanov, Anna Mihaylova, Penka Petleshkova, and Stanislava Ivanova
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Ajmalicine ,Traditional medicine ,business.industry ,Discontinuation ,Yohimbine ,Pausinystalia yohimbe ,chemistry.chemical_compound ,Blood pressure ,chemistry ,visual_art ,Heart rate ,visual_art.visual_art_medium ,Medicine ,Bark ,business ,Sibutramine ,medicine.drug - Abstract
After the intake of a yohimbine bark food supplement a thirty-eight-year old man declared serious complaints: headache, rapid heart rate, high blood pressure, cold sweating, rush, tremor. The patient took only 1 capsule per day every morning for two days. After the discontinuation of supplementation the symptoms disappeared. The purpose of the study was to determine the factors causing the described side effects. Series of analyses were performed: HPLC/MS and GC/MS. Yohimbine bark contains a number of different alkaloids. It was important to be established the content of the main alkaloidyohimbine because the content of yohimbine was not declared on the label. We also suspected the presence of undeclared sibutramine. The screening did not find presence of sibutramine but it was found that the total content of yohimbine in 1 capsule was 50 mg. 50 mg of yohimbine per 1 capsule is extremely high dose- the approved daily dose of yohimbine in medicinal product is up to 30 mg/person/ day. We also established presence of α-yohimbine (ajmalicine) in high levels. We consider that the total content of yohimbine should be declared on the label of every food supplement which contains yohimbine bark, otherwise the customers would be exposed to risk.
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- 2019
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42. Osteoporosis: Therapeutic Options
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Lily Peikova, Stefka Ivanova, Liliya V. Vasileva, Stanislava Ivanova, and Danka Obreshkova
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medicine.medical_specialty ,structure-activity ,Hormone Replacement Therapy ,medicine.medical_treatment ,Osteoporosis ,lcsh:Medicine ,030209 endocrinology & metabolism ,Phytoestrogens ,Bone fragility ,Bone tissue ,World health ,Pharmacological treatment ,03 medical and health sciences ,0302 clinical medicine ,prevention ,Vitamin D and neurology ,Medicine ,Humans ,030212 general & internal medicine ,Intensive care medicine ,Bone mineral ,treatment ,business.industry ,lcsh:R ,Hormone replacement therapy (menopause) ,General Medicine ,medicine.disease ,osteoporosis ,medicine.anatomical_structure ,Physical therapy ,pharmacology ,business - Abstract
The definition of osteoporosis was originally formulated at a conference of the World Health Organization (WHO) in 1993 as ‘a systemic skeletal disease characterized by decreased bone mass and altered micro-architecture of bone tissue, leading to enhanced bone fragility and risk of fractures’. Osteoporosis is characterized by low bone mineral density (BMD) and loss of the structural and bio-mechanical properties that are required to maintain bone homeostasis. This review aims to address the currently available options in prevention and treatment of osteoporosis. Management of osteoporosis includes non-pharmacological treatment - diet rich of calcium and vitamin D, healthy lifestyle, proper exercise plan, and pharmacological therapy. Combination of non-pharmacological and pharmacological treatment options have to be considered for prevention of osteoporosis and minimization of the risk of fractures. Given the heterogeneity of osteoporosis syndrome and lack of significant number of comparative studies, the choice of a pharmacological agents should be individualized.
- Published
- 2015
43. Frequency of hyaline membrane disease in preterm infants after prenatal corticosteroid prophylaxis
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Ekaterina Uchicova, Kalin Ivanov, eva, Anna Mihaylova, Milena S, Stanislav Gueorguiev, Emilia Karaslavova, Elina Petkova-Gueorguieva, Nikoleta Parahuleva, and Stanislava Ivanova
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Pulmonary and Respiratory Medicine ,Pediatrics ,medicine.medical_specialty ,Respiratory distress ,business.industry ,Incidence (epidemiology) ,Gestational age ,Retrospective cohort study ,Disease ,medicine.disease ,Premature birth ,Pediatrics, Perinatology and Child Health ,Medicine ,business ,Hyaline ,Dexamethasone ,medicine.drug - Abstract
Premature birth is a serious medical, social and economic problem. Its consequences are multiple health complications leading to high neonatal mortality worldwide. Respiratory insufficiency and surfactant deficiency significantly increase the risk of developing Hyaline Membrane Disease (HMD) and other forms of Respiratory Distress (RDS). These are the most common causes of death in premature babies. In prenatal and neonatal medicine, new and adaptive prophylaxis is being implemented to reduce the risk of death of premature babies and reduce the development of health complications. The goal of effective corticosteroid prophylaxis is to reduce mortality, reduce complications in prenatal new-borns, and shorten their stay in neonatal and intensive units respectively. A retrospective study of 167 preterm infants was conducted, of which 89 (53.3%) had prophylaxis with dexamethasone. In 25 (15%) of preterm infants, there was a Hyaline Membrane Disease (HMD) and 101 (60.5%) developed other forms of Respiratory Distress Syndrome (RDS). The results obtained show that the incidence of HMD in preterm infants is mediated by the early gestational age and advanced age of the mother, and decreased by corticosteroid therapy.
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- 2018
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- View/download PDF
44. The use of dietary supplements by professional athletes
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Kalin Ivanov, Elina Petkova, Stanislava Ivanova, and Stanislav Gueorguiev
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Pulmonary and Respiratory Medicine ,Professional sport ,biology ,Athletes ,business.industry ,010401 analytical chemistry ,030229 sport sciences ,biology.organism_classification ,01 natural sciences ,humanities ,0104 chemical sciences ,03 medical and health sciences ,0302 clinical medicine ,Environmental health ,Pediatrics, Perinatology and Child Health ,Medicine ,Health risk ,business - Abstract
Professional athletes are exposed to everyday intensive physical strain. In order to provide for the energy demands of the organism, the athletes consume various food supplements. A specially designed questionnaire was used to convey an anonymous survey of a random sample of 66 professional athletes. The aim of the present research was to assess the intake of the most popular food supplements used in professional sport. The results of the survey confirmed that professional athletes are fully informed about the benefits provided by the intake of food supplements but were not well aware of the health risk hidden in some formulations and accepted them as safe products. ?mino acids had the largest consumption rate among food supplements, followed by proteins, magnesium, creatine and others
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- 2018
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45. Conservative therapy options for the treatment of coxarthrosis in the early stage of the condition
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Kalin Ivanov, Stanislava Ivanova, Vasil G. Madzharov, Stanislav Gueorguiev, Petya Kasnakova, Penka Petleshkova, Anna Mihaylova, and Elina Petkova-Gueorguieva
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Pulmonary and Respiratory Medicine ,education.field_of_study ,medicine.medical_specialty ,Rehabilitation ,business.industry ,medicine.medical_treatment ,Population ,Pharmacotherapy ,Quality of life ,Pediatrics, Perinatology and Child Health ,Interferential current ,medicine ,Physical therapy ,Stage (cooking) ,Range of motion ,education ,business ,Pathological - Abstract
Aim: Arthrosis of the hip joint is a condition that is becoming more and more common-it affects 1% of the population and constitutes a serious problem for their working efficiency and active way of life. The deforming arthrosis limits the functional capacity of the affected patients, worsens their quality of life and leads to incapacitation of the patients. The treatment of patients with coxarthrosis has to be planned and carried out comprehensively, in accordance with the pathological findings, the stage, duration and individual abilities of each patient. In the early stages of the condition, conservative therapy plays an essential role in the prophylaxis of complications and in slowing down the process. Physical and rehabilitation methods, in combination with medicamentous therapy, yield good results. This article focuses on the application of the comprehensive effect of conservative physiotherapeutic methods and complementary drug therapy in the early stage of coxarthrosis. The aim of the study is to investigate the efficiency of the combined application of physiotherapeutic electrical procedures and kinesitherapy methods and means in the treatment of coxarthrosis in the initial stage. Material and Methods: 18 out-patients with coxarthrosis at an average age of 68, were subjected to a treatment schedule including: interferential current, low-frequency magnetic field, ultra phoresis with non-steroid anti-inflammatory medications, followed by a program of remedial exercise administered in 2 courses of 7 d at ‘St. Panteleymon’ Hospital in Plovdiv, in the period from September 2017 to May 2018. Results: The range of motion in terms of degrees exhibits a tendency towards increasing at the end of the course of therapy, as compared to that at the beginning of the course. The results from the initial and final muscle tests of the hip joint showed an improvement of the muscle function (from a degree of 3.50 to a degree of 4.50). Conclusion: In patients with coxarthrosis in the initial stage, the pain subsides after the physical and rehabilitation therapy administered in combination with medications.
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- 2018
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46. Detection of sibutramine in herbal food supplements by UHPLC/HRMS and UHPLC/MS-MS
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Vasil G. Madzharov, Elina Petkova-Gueorguieva, Anna Mihaylova, Stanislav Gueorguiev, Stanislava Ivanova, and Kalin Ivanov
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Pulmonary and Respiratory Medicine ,Health consequences ,Traditional medicine ,business.industry ,Uhplc hrms ,02 engineering and technology ,021001 nanoscience & nanotechnology ,030226 pharmacology & pharmacy ,Uhplc ms ms ,03 medical and health sciences ,0302 clinical medicine ,Weight loss ,Pediatrics, Perinatology and Child Health ,Medicine ,medicine.symptom ,0210 nano-technology ,business ,Public awareness ,Sibutramine ,medicine.drug - Abstract
Recent studies have announced that many food supplements for weight loss contained undeclared sibutramine. We have analysed 10 samples of herbal weight loss food supplements (FS) by HPLC/HRMS and UHPLC/MS-MS. We have established that two of the analysed samples contained sibutramine: respectively 5 μg/per capsule and 20 μg/per capsule. Illegal inclusion of this substance in FS could cause serious side effects and long term health consequences. The regulatory requirements for FS should be enhanced for more comprehensive consumers’ protection. The need for mandatory quality control of these products and public awareness is undeniable.
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- 2018
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47. Design, Synthesis, Biological Evaluation, and NMR Studies of a New Series of Arylsulfones As Selective and Potent Matrix Metalloproteinase-12 Inhibitors
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Laura Panelli, Elisabetta Orlandini, Salvatore Santamaria, Elisa Nuti, Stanislava Ivanova Avramova, Nicola D'Amelio, Alessandro Maiocchi, Tiziano Tuccinardi, Fulvio Uggeri, F Casalini, Armando Rossello, Giovanni Cercignani, Adriano Martinelli, and Susanna Nencetti
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Models, Molecular ,Magnetic Resonance Spectroscopy ,Hydroxamic acid ,Molecular model ,Matrix metalloproteinase inhibitor ,Molecular Conformation ,Matrix Metalloproteinase Inhibitors ,Matrix metalloproteinase ,Chemical synthesis ,Macrophage elastase ,In vitro ,Inhibitory Concentration 50 ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Docking (molecular) ,Drug Design ,Matrix Metalloproteinase 12 ,Drug Discovery ,Humans ,Molecular Medicine ,Protease Inhibitors ,Sulfones - Abstract
Overexpression of macrophage elastase (MMP-12), a member of the matrix metalloproteinases family, can be linked to tissue remodeling and degradation in some inflammatory processes, such as chronic obstructive pulmonary disease (COPD), emphysema, rheumatoid arthritis (RA), and atherosclerosis. On this basis, MMP-12 can be considered an attractive target for studying selective inhibitors that are useful in the development of new therapies for COPD and other inflammatory diseases. We report herein the design, synthesis, and in vitro evaluation of a new series of compounds, possessing an arylsulfonyl scaffold, for their potential as selective inhibitors of MMP-12. The best compound in the series showed an IC50 value of 0.2 nM, with good selectivity over MMP-1 and MMP-14. A docking study was carried out on this compound in order to investigate its binding interactions with MMP-12, and NMR studies on the complex with the MMP-12 catalytic domain were able to validate the proposed binding mode.
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- 2009
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48. Le Traitement Antibiotique Dans La Pédiatrie
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E. Petkova, Zlatka Dimitrova, S. Papanov, Vania Georgieva, Stanislava Ivanova, Rumen Mladenov, and Kalin Ivanov
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medicine.medical_specialty ,Pediatrics ,Cefotaxime ,business.industry ,medicine.drug_class ,Cephalosporin ,Antibiotics ,Amoxicillin ,Antimicrobial ,Third generation cephalosporins ,polycyclic compounds ,medicine ,Gentamicin ,Intensive care medicine ,business ,Cefaclor ,medicine.drug - Abstract
The current study should be paid extra attention because antibiotics are main cluster of drugs for treatment of child infections and illnesses. They are the most commonly prescribed medicines for children, relatively expensive and consume 60-70% of the budget for treatment of child illnesses, with exclusion only in malign sickness. OBJECT: The current study represents common classification of antibiotics and the most commonly used antimicrobial agents during childhood. RESEARCH METHODS - Systematic approach and critical analysis of the available scientific periodicals - Interview method of the survey (survey data pediatricians and general practitioners in the region of Plovdiv, Bulgaria.) - Own research on the issue. RESULTS AND DISCUSSION: Most often, doctors use: Broad-spectrum penicillins: Amoxicillin, Amopen, Ospamox, Duomox First generation cephalosporins: Ospexin, Cephalexin Second-generation cephalosporins: Cefaclor Third generation cephalosporins: Abricef, Cefotaxime, Rocephin, Fortum Fourth generation cephalosporins: Maxipime Macrolides: Macropen Aminoglycosides: Gentamicin, Amicacine CONCLUSION: No significant differences are observed in the prescribed by the general practitioners and pediatricians antibiotics.
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- 2016
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49. HPLC detection of dehydroepiandrosterone in food additives by using normal phase HPLC
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Rumen Mladenov, Danka Obreshkova, Stanislava Ivanova, Plamen Stoyanov, Stefka Ivanova, and Kalin Ivanov
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chemistry.chemical_compound ,Bioanalysis ,Chromatography ,food.ingredient ,food ,chemistry ,Elution ,Normal phase ,Food additive ,Diol ,Dehydroepiandrosterone ,Acetonitrile ,High-performance liquid chromatography - Abstract
A normal-phase High Performance Liquid Chromatography (HPLC) method was developed for the determination of dehydroepiandrosterone (DHEA) in food supplements. We have used an HPLC 200 (Perkin Elmer, USA) with a spectrophotometric detector LC-785A (Bioanalytical systems, USA) and a thermostat (Perkin Elmer, Waltham, MA, USA). We have chosen isocratic HPLC elution, column: LiChrospher (100 DIOL 250 x 4 mm х 5 μm), mobile phase: acetonitrile: water = 98: 2 v/v, flow rate: 1 ml/min. and detection at λ = 202 nm. We have found that this method allows fast and selective qualitative and quantitative determination of DHEA in pharmaceutical products.
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- 2016
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50. Potent arylsulfonamide inhibitors of tumor necrosis factor-alpha converting enzyme able to reduce activated leukocyte cell adhesion molecule shedding in cancer cell models
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Salvatore Santamaria, Vittorio Limongelli, Susanna Nencetti, F Casalini, Ettore Novellino, Armando Rossello, Luciana Marinelli, Valeria La Pietra, Stanislava Ivanova Avramova, Elisabetta Orlandini, Elisa Nuti, Silvano Ferrini, Giovanni Cercignani, Marina Fabbi, Nuti, E., Casalini, F., Avramova, S. i., Santamaria, S., Fabbi, M., Ferrini, S., Marinelli, Luciana, LA PIETRA, Valeria, Limongelli, Vittorio, Novellino, Ettore, Cercignani, G., Orlandini, E., Nencetti, S., and Rossello, A.
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Models, Molecular ,Blotting, Western ,Motility ,Enzyme-Linked Immunosorbent Assay ,ADAM17 Protein ,Hydroxamic Acids ,Structure-Activity Relationship ,Activated-Leukocyte Cell Adhesion Molecule ,Cell Line, Tumor ,Drug Discovery ,Structure–activity relationship ,Humans ,Enzyme Inhibitors ,ALCAM ,Enzyme Assays ,chemistry.chemical_classification ,Ovarian Neoplasms ,Sulfonamides ,Dose-Response Relationship, Drug ,Molecular Structure ,Cell biology ,carbohydrates (lipids) ,ADAM Proteins ,Kinetics ,Enzyme ,chemistry ,Models, Chemical ,Cell culture ,Cancer cell ,Molecular Medicine ,Female ,Protein Binding - Abstract
Activated leukocyte cell adhesion molecule (ALCAM) plays a relevant role in tumor biology and progression. Our previous studies showed that ALCAM is expressed at the surface of epithelial ovarian cancer (EOC) cells and is released in a soluble form by ADAM-17-mediated shedding. This process is relevant to EOC cell motility and invasiveness, which is reduced by nonspecific inhibitors of ADAM-17. For this reason, ADAM-17 may represent a new useful target in anticancer therapy. Herein, we report the synthesis and biological evaluation of new ADAM-17 inhibitors containing an arylsulfonamidic scaffold. Among the new potential inhibitors, two very promising compounds 17 and 18 were discovered, with a nanomolar activity for ADAM-17 isolated enzyme. These compounds proved to be also the most potent in inhibiting soluble ALCAM release in cancer cells, showing a nanomolar activity on A2774 and SKOV3 cell lines.
- Published
- 2010
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