Katerina Todorova

Dr. Katerina Todorova

orcid

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 June 2024 in Chemical Engineering Journal
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GFGuillem Ferreres
Guillem Ferreres
SPSílvia Pérez-Rafael
Sílvia Pérez-Rafael
ÒPÒscar Palacios
Òscar Palacios
KTKaterina Todorova
Katerina Todorova
DHDolores Hinojosa-Caballero
Dolores Hinojosa-Caballero
TTTzanko Tzanov
Tzanko Tzanov

26 May 2023 in Biomedicines
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AGAni Georgieva
Ani Georgieva
KTKaterina Todorova
Katerina Todorova
IIIvan Angelov Iliev
Ivan Angelov Iliev
VDValeria Dilcheva
Valeria Dilcheva
IVIvelin Vladov
Ivelin Vladov
RTReneta Toshkova
Reneta Toshkova
Hemocyanins are oxygen-transporting glycoproteins in the hemolymph of some invertebrate species that attracted scientific interest as potential anticancer agents. The present study aims to assess the in vitro and in vivo anticancer activity of hemocyanins isolated from Helix aspersa, Helix lucorum, and Rapana venosa in the Graffi myeloid tumor model. The in vitro antitumor activity of the hemocyanins was determined by a MTT test and cytomorphological analysis by fluorescent and transmission electron microscopy. The in vivo effects of the hemocyanins were examined in hamsters transplanted with Graffi tumor. The serum antibody titers against the tested hemocyanins and tumor antigen were determined by ELISA. Histopathological assessment of the morphological features related to antitumor effect, immune system response, and toxicity in some internal organs was performed. The results of in vitro studies indicated that the tested hemocyanins induced significant antiproliferative and apoptogenic effects. The in vivo investigations demonstrated a protective antitumor effect, expressed in reduced transplantability, suppression of tumor growth and metastasis, reduced mortality, prolonged survival time, and absence of toxic side effects. The present study indicated that the antitumor activity of the studied hemocyanins was due to both immune stimulation and direct effects on the tumor cells, and they displayed their potential as therapeutic agents against hematological malignances.

26 June 2020 in Viruses
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ASAlīna Sultanova
Alīna Sultanova
MCMaksims Cistjakovs
Maksims Cistjakovs
LSLiba Sokolovska
Liba Sokolovska
KTKaterina Todorova
Katerina Todorova
ECEgils Cunskis
Egils Cunskis
Modra MurovskaModra Murovska
Modra Murovska
The aim of this study was to investigate the role of human herpesvirus-6 (HHV-6) in autoimmune thyroiditis (AIT) development. We examined the possible involvement of HHV-6 gene expression encoding immunomodulating proteins U12 and U51 in AIT development and their role in the modulation of chemokine signaling. One hundred patients with autoimmune thyroiditis following thyroidectomy were enrolled in this study. Nested polymerase chain reaction (nPCR) was used to detect the HHV-6 sequence in DNA samples. Reverse transcription PCR (RT-PCR) with three different HHV-6 gene targets (U79/80, U51 and U12) was to detect active infection markers. HHV-6 load was identified using a commercial real-time PCR kit. Immunohistochemistry was performed to investigate the expression of the HHV-6 antigen and RANTES (Regulated upon Activation, Normal T Cell Expressed and Secreted) in thyroid gland tissue. Different commercial immunosorbent assay kits were used for the detection of RANTES, IFNγ, IL-6, and TNFα levels in the AIT patient group and controls. We detected 98% presence of the HHV-6 genomic sequence in AIT patients’ thyroid gland tissues. Markers of active HHV-6 infection (HHV-6 U79/80, U12 and/or U51 mRNA) were predominant in AIT patients’ thyroid tissue samples in comparison with the control group (56% vs. 6%). Evidence from immunofluorescence microscopy showed that HHV-6 can persist in thyrocytes and can interact with RANTES. Visual confirmation of the intense immunofluorescence signal of RANTES detected in thyroid tissues could indicate high expression of this chemokine in the thyroid gland. On the other hand, immunosorbent assays showed very low RANTES levels in AIT patients’ peripheral plasma. These results indicate that RANTES level in AIT patients could be influenced by HHV-6 activation, which in turn may aid AIT development.

1 October 2021 in Journal of microbiology, biotechnology and food sciences
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TTTanya Toshkova-Yotova
Tanya Toshkova-Yotova
AGAni Georgieva
Ani Georgieva
KTKaterina Todorova
Katerina Todorova
PPPlamen Pilarski
Plamen Pilarski
RTReneta Toshkova
Reneta Toshkova
Microalgae are of great importance for the production of original natural substances of interest for food, health or biotechnological applications. Mass cultures of green microalgae are used for production of carotenoids such β-carotene, astaxanthin, canthaxanthin, lutein etc. The aim of this study was to obtain an oil extract from a Bulgarian green microalga strain Coelastrella sp. BGV and to assess its anticancer and apoptogenic activity in vitro against human tumor cells HeLa by means of MTT and fluorescence microscopy analyses. The results showed that the oil extract obtained by a direct extraction using a common vegetable oil reduces proliferation and induces apoptosis in HeLa cells. In contrast to widely used organic solvents for the production of carotenoids, the applied bio-solvent (sunflower oil) can be a valuable alternative approach for the needs of the food industry. The resulting oil extract showed promising antitumor and apoptosis-inducing activity against HeLa cells in vitro and potential for future use in practice.

20 January 2023 in Gels
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KRKonstans Ruseva
Konstans Ruseva
KTKaterina Todorova
Katerina Todorova
TZTanya Zhivkova
Tanya Zhivkova
RMRositsa Milcheva
Rositsa Milcheva
DIDimitar Ivanov
Dimitar Ivanov
EVElena Vassileva
Elena Vassileva
The study reports the synthesis and characterization of novel triple stimuli responsive interpenetrating polymer network (IPN) based on two polyzwitterionic networks, namely of poly(carboxybetaine methacrylate) and poly(sulfobetaine methacrylate). The zwitterionic IPN hydrogel demonstrates the ability to expand or shrink in response to changes in three “biological” external stimuli such as temperature, pH, and salt concentration. The IPN hydrogel shows good mechanical stability. In addition, other important features such as non-cytotoxicity and antibiofouling activity against three widespread bacteria as P. Aeruginosa, A. Baumanii, and K. Pneumoniae are demonstrated. The in vivo behavior of the novel zwitterionic IPN hydrogel suggests that this smart material has very good potential as a biomaterial.

Verified
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ISInna Sulikovska
Inna Sulikovska
AGAni Georgieva
Ani Georgieva
VDVera Djeliova
Vera Djeliova
KTKaterina Todorova
Katerina Todorova
AVAnelia Vasileva
Anelia Vasileva
MDMashenka Dimitrova
Mashenka Dimitrova
The present paper aims to assess the antitumor activity of ethyl acetate/water soluble fraction obtained from the extract of Tanacetum vulgare L. leaves and flowers (EATV). The chemical composition of EATV was determined by LC-HPMS. In vitro studies were performed on the HT-29 cell line (human colorectal carcinoma). The effect on the cell cycle and the pro-apoptotic activity were evaluated using flow cytometry analyses. Genotoxicity was analyzed by the comet assay. In vivo antitumor potential of EATV was assessed in Ehrlich’s tumor-bearing mice. Pathological, histological, and hematological analyses of the EATV-treated animals were performed, and the effect of the treatment on the lifespan was evaluated. The LC-HRMS analysis demonstrated a complex phytochemical profile of EATV comprising more than forty compounds, thirty-six of which were identified. The results showed that the antitumor activity of EATV towards HT-29 cells is due to a pronounced genotoxicity leading to cell cycle arrest and apoptosis of the cells. Pathological studies revealed more massive and frequently detected tumor necrosis, apoptosis, and fistulation in T. vulgare-treated mice compared to positive tumor-bearing controls. Furthermore, it was demonstrated that the intraperitoneal application of EATV prolonged the animal’s lifespan.