Liana Mkrtchyan - Academia.edu (original) (raw)

Papers by Liana Mkrtchyan

NATO Security through Science Series

The aim of this study was to compare the level of somatic mutagenesis in women with benign tumors... more The aim of this study was to compare the level of somatic mutagenesis in women with benign tumors of the reproductive system living in radiation contaminated regions of the Russian Federation with that in unexposed healthy individuals. Frequency of peripheral blood lymphocytes bearing mutations at T-cell receptor (TCR) locus was assessed by flow cytometry in 219 patients with myoma who

Journal of General Physiology

KCNQ1 voltage-gated K+ channels are involved in a wide variety of fundamental physiological proce... more KCNQ1 voltage-gated K+ channels are involved in a wide variety of fundamental physiological processes and exhibit the unique feature of being markedly inhibited by external K+. Despite the potential role of this regulatory mechanism in distinct physiological and pathological processes, its exact underpinnings are not well understood. In this study, using extensive mutagenesis, molecular dynamics simulations, and single-channel recordings, we delineate the molecular mechanism of KCNQ1 modulation by external K+. First, we demonstrate the involvement of the selectivity filter in the external K+ sensitivity of the channel. Then, we show that external K+ binds to the vacant outermost ion coordination site of the selectivity filter inducing a diminution in the unitary conductance of the channel. The larger reduction in the unitary conductance compared to whole-cell currents suggests an additional modulatory effect of external K+ on the channel. Further, we show that the external K+ sensit...

International Journal of Molecular Sciences, 2021

Radio- and chemoresistance of cancer stem cells (CSCs) is considered as one of the possible cause... more Radio- and chemoresistance of cancer stem cells (CSCs) is considered as one of the possible causes of adverse results of chemoradiotherapy for various malignancies, including cervical cancer. However, little is known about quantitative changes in the CSC subpopulation in the course of treatment and mechanisms for individual response of CSCs to therapy. The purpose of the study was to evaluate the association of radiation response of cervical CSCs with clinical and morphological parameters of disease and features of human papillomavirus (HPV) infection. The proportion of CD44+CD24low CSCs was determined by flow cytometry in cervical scrapings from 55 patients with squamous cell carcinoma of uterine cervix before treatment and after fractionated irradiation at a total dose of 10 Gy. Real-time PCR assay was used to evaluate molecular parameters of HPV DNA. Post-radiation increase in the CSC proportion was found in 47.3% of patients. Clinical and morphological parameters (stage, status ...

Problems in oncology, 2019

Purpose: to estimate the efficiency of the concurrent chemoradiotherapy (CRT) and radiotherapy (R... more Purpose: to estimate the efficiency of the concurrent chemoradiotherapy (CRT) and radiotherapy (RT) alone for patients with the locally advanced cervical cancer (CC) taking into account prognostic factors. Material and methods: The research included 335 patients with morphologically verified CC of the П-Ш stage on FIGO: 150 patients underwent RT (group 1): 185 patients - CRT with cisplatin and 5-fluorouracil (group 2). Patients in the group 1 were significantly older than patients of the group 2. The disease of the Stage III, parametric variant of the spread of the tumor, as well as metastatic lesions of the pelvic lymph nodes occurred more frequently in the group 2. Results: In the group 1 complete response to treatment occurred in 98 cases (52.9%), while in the group 2 demonstrated - 64 (42.7%) patients (p < 0.01). Radioepithelitis of Grade 1 and 2 occurred more frequently in patients underwent CRT in this group haematologic and gastrointestinal toxicity was moderate and severe...

NATO Security through Science Series

The aim of this study was to compare the level of somatic mutagenesis in women with benign tumors... more The aim of this study was to compare the level of somatic mutagenesis in women with benign tumors of the reproductive system living in radiation contaminated regions of the Russian Federation with that in unexposed healthy individuals. Frequency of peripheral blood lymphocytes bearing mutations at T-cell receptor (TCR) locus was assessed by flow cytometry in 219 patients with myoma who

Journal of General Physiology

KCNQ1 voltage-gated K+ channels are involved in a wide variety of fundamental physiological proce... more KCNQ1 voltage-gated K+ channels are involved in a wide variety of fundamental physiological processes and exhibit the unique feature of being markedly inhibited by external K+. Despite the potential role of this regulatory mechanism in distinct physiological and pathological processes, its exact underpinnings are not well understood. In this study, using extensive mutagenesis, molecular dynamics simulations, and single-channel recordings, we delineate the molecular mechanism of KCNQ1 modulation by external K+. First, we demonstrate the involvement of the selectivity filter in the external K+ sensitivity of the channel. Then, we show that external K+ binds to the vacant outermost ion coordination site of the selectivity filter inducing a diminution in the unitary conductance of the channel. The larger reduction in the unitary conductance compared to whole-cell currents suggests an additional modulatory effect of external K+ on the channel. Further, we show that the external K+ sensit...

International Journal of Molecular Sciences, 2021

Radio- and chemoresistance of cancer stem cells (CSCs) is considered as one of the possible cause... more Radio- and chemoresistance of cancer stem cells (CSCs) is considered as one of the possible causes of adverse results of chemoradiotherapy for various malignancies, including cervical cancer. However, little is known about quantitative changes in the CSC subpopulation in the course of treatment and mechanisms for individual response of CSCs to therapy. The purpose of the study was to evaluate the association of radiation response of cervical CSCs with clinical and morphological parameters of disease and features of human papillomavirus (HPV) infection. The proportion of CD44+CD24low CSCs was determined by flow cytometry in cervical scrapings from 55 patients with squamous cell carcinoma of uterine cervix before treatment and after fractionated irradiation at a total dose of 10 Gy. Real-time PCR assay was used to evaluate molecular parameters of HPV DNA. Post-radiation increase in the CSC proportion was found in 47.3% of patients. Clinical and morphological parameters (stage, status ...

Problems in oncology, 2019

Purpose: to estimate the efficiency of the concurrent chemoradiotherapy (CRT) and radiotherapy (R... more Purpose: to estimate the efficiency of the concurrent chemoradiotherapy (CRT) and radiotherapy (RT) alone for patients with the locally advanced cervical cancer (CC) taking into account prognostic factors. Material and methods: The research included 335 patients with morphologically verified CC of the П-Ш stage on FIGO: 150 patients underwent RT (group 1): 185 patients - CRT with cisplatin and 5-fluorouracil (group 2). Patients in the group 1 were significantly older than patients of the group 2. The disease of the Stage III, parametric variant of the spread of the tumor, as well as metastatic lesions of the pelvic lymph nodes occurred more frequently in the group 2. Results: In the group 1 complete response to treatment occurred in 98 cases (52.9%), while in the group 2 demonstrated - 64 (42.7%) patients (p < 0.01). Radioepithelitis of Grade 1 and 2 occurred more frequently in patients underwent CRT in this group haematologic and gastrointestinal toxicity was moderate and severe...