Nino Asatiani - Academia.edu (original) (raw)

Papers by Nino Asatiani

European Heart Journal Supplements, Aug 1, 2020

European Heart Journal Supplements, 2020

Hypertension (HTN) is highly prevalent and the leading cardiovascular risk factor for death globa... more Hypertension (HTN) is highly prevalent and the leading cardiovascular risk factor for death globally. A large proportion of individuals with high blood pressure (BP) are unaware leading to under treatment and poor control. To address this, the International Society of Hypertension (ISH) initiated a global mass screening campaign, the May Measurement Month 2017 (MMM17), in which Kenya participated. Following the success of the campaign, its successor MMM18 was launched. Here, we present the Kenyan results for MMM18. Opportunistic screening of consenting adults was done in various sites across Kenya in May 2018, by volunteers trained using ISH material, under the co-ordination of the Kenya Cardiac Society. Blood pressure, pulse rate, weight, and height were measured by standard methods. Definitions of HTN and statistical methods all adhered to the standard MMM protocol. We screened 49 548 subjects, mean age 39.95 (15.3) years. In total, 49.4% had never had a BP measurement taken. Afte...

Toxics

The dose-dependent effects of single metals (Zn, Ni, and Cu) and their combinations at steady tim... more The dose-dependent effects of single metals (Zn, Ni, and Cu) and their combinations at steady time-actions on the cell viability of the bacteria Shewanella xiamenensis DCB 2-1, isolated from a radionuclide-contaminated area, have been estimated. The accumulation of metals by Shewanella xiamenensis DCB 2-1 in single and multi-metal systems was assessed using the inductively coupled plasma atomic emission spectroscopy. To estimate the response of the bacteria’s antioxidant defense system, doses of 20 and 50 mg/L of single studied metals and 20 mg/L of each metal in their combinations (non-toxic doses, determined by the colony-forming viability assay) were used. Emphasis was given to catalase and superoxide dismutase since they form the primary line of defense against heavy metal action and their regulatory circuit of activity is crucial. The effect of metal ions on total thiol content, an indicator of cellular redox homeostasis, in bacterial cells was evaluated. Genome sequencing of S...

Environmental Sciences

Polyhydroxyalkanoates (PHAs) are biopolymers produced by numerous bacteria and can be used in the... more Polyhydroxyalkanoates (PHAs) are biopolymers produced by numerous bacteria and can be used in the production of bioplastics. PHAs are synthesized by microorganisms by fermentation of carbon sources. Due to the different monomer structures of PHAs, there are many kinds of PHAs, and their corresponding material properties are also very different. Thus, the search for bacteria producing the PHAs is of great interest. In this study, the bacteria isolated from the environment were analyzed for the presence of PHA. PHA production was tested with staining methods Sudan Black B, Nile Blue, and Nile Red. The presence of a PHA synthase gene (phaC) was confirmed by PCR amplification. PHAs were extracted from the strains and characterized by the FTIR spectroscopy method. A biochip for a fast screening of environmental samples for the presence of PHA-producing bacteria was designed. The biochip contained 11 probes for coding class 1, 2, and 3 PHA synthase genes.

The Scientific World JOURNAL, 2003

This is the first of a series of calorimetric studies designed to characterize and understand sur... more This is the first of a series of calorimetric studies designed to characterize and understand survival mechanisms of metal-reducing bacteria isolated from metal-polluted environments. In this paper we introduce a new concept of thermal spectrum of the endothermic melting ofcomplex biological systems (e.g., proteins, nucleic acids, ribosomes, membrane structures)in intact cells. Allthermal spectra measured are thermograms that describe the temperature dependence of heat capacity change of the complex systems of biologically active substances in bacterial cells. This new concept of thermal spectrum was applied to investigate spectral features from intact cells of Cr(VI)-reducer Arthrobacter oxydans at different points of their growth conditions and stages. Over the temperature range of 40–105°C, we observed that spectral changes are particularly significant in the 40–90°C interval. This may correspond to the orderly changes in subcellular structural elements: proteins, ribosomes and R...

Current Microbiology, 2004

Arthrobacter species is of interest because of its high potential for bioremediation. Bacteria ca... more Arthrobacter species is of interest because of its high potential for bioremediation. Bacteria can detoxify chromium, by either reduction or accumulation inside the bacteria and/or absorption of chromium(VI) (CrVI) on their surface, and efflux pump. The possible pathway of Cr(VI) reduction by Arthrobacter oxydans isolated from Columbia basalt rocks at a US DOE highly contaminated site (USA) has been considered in the present study. FTIR absorption spectroscopy showed that these bacteria reduce Cr(VI). In the present study the threshold Cr(VI) nontoxic concentration (35 g/mL) for A. oxydans growing in liquid medium was estimated. Complete uptake of this concentration was achieved in about 10 days after chromium addition into the medium. At this concentration an increase in the protein isolated from the cell wall of A. oxydans was observed. This increased protein predominated independently of the growth phase at which Cr(VI) was added. Thermal analysis was used to identify any influence of Cr(VI) on the DNP complex of A. oxydans. According to the data obtained it can be supposed that Cr(VI) reduction predominantly occurs on the bacterial surface and that cell wall represents a permeable barrier for these bacteria at the non-toxic chromium action.

The Scientific World JOURNAL, 2004

In the present study, the antioxidant capacity of chromium-treated L-41 (human epithelial-like ce... more In the present study, the antioxidant capacity of chromium-treated L-41 (human epithelial-like cells) was investigated by the ESR spin-trapping technique. The crude cell extracts of the cells grown in the presence of 2 µM (nontoxic) and 20 µM (toxic) chromium (VI) concentrations were tested in the model Fenton system with and without catalase-inhibitor sodium azide. The presented approach using the ESR technique along with inhibitors lets us discern cell extract defense capacity connected with the enzymatic activity in viable cells and the catabolic activity in dying cells.

Journal of Inorganic Biochemistry, 2004

In order to investigate the low-dose long-term Cr(VI) action on antioxidant enzymes in cultured m... more In order to investigate the low-dose long-term Cr(VI) action on antioxidant enzymes in cultured mammalian cells we estimated the activity of glutathione dependent antioxidant enzymes, catalase and superoxide dismutase (SOD) under various chromium concentrations in human epithelial-like L-41 cells. The long-term action of 20 lM causes the toxicity that results in losing of the cell viability by activating the apoptotic process, as identified by morphological analysis, the activation of caspase-3, and DNA fragmentation. The toxic chromium concentration totally destroys glutathione antioxidant system, and diminishes the activity of catalase and cytosolic Cu, ZnSOD. The non-toxic concentration (2 lM) causes the activation of the antioxidant defense systems, and they neutralize the oxidative impact.

Biosensors, 2021

Allergenicity assessment of transgenic plants and foods is important for food safety, labeling re... more Allergenicity assessment of transgenic plants and foods is important for food safety, labeling regulations, and health protection. The aim of this study was to develop an effective multi-allergen diagnostic approach for transgenic soybean assessment. For this purpose, multiplex polymerase chain reaction (PCR) coupled with DNA chip technology was employed. The study was focused on the herbicide-resistant Roundup Ready soya (RRS) using a set of certified reference materials consisting of 0, 0.1%, 0.5%, and 10% RRS. Technically, the procedure included design of PCR primers and probes; genomic DNA extraction; development of uniplex and multiplex PCR systems; DNA analysis by agarose gel electrophoresis; microarray development, hybridization, and scanning. The use of the asymmetric multiplex PCR method is shown to be very efficient for DNA hybridization with biochip probes. We demonstrate that newly developed fourplex PCR methods coupled with DNA-biochips enable simultaneous identificatio...

Arsenic [Working Title], 2021

The study is devoted to a very urgent and acute problem for Georgia – remediation/restoration of ... more The study is devoted to a very urgent and acute problem for Georgia – remediation/restoration of the arsenic (As) mining and storage sites. The approach of a given work is based on using capabilities of nature itself, which has a great adaptive potential to chemical environmental pollution. The aim of the study is to identify the bacterial strains from the endemic soil microbiota, characteristic to a specific localization of arsenic contaminated sites and able to resist to the toxicant. To determine the level of arsenic contamination, soil samples have been analyzed using Inductively Coupled Plasma - Optical Emission Spectrometry method. The distribution of arsenic in soil samples splits them into categories according to the degree of contamination, ranging from 50 ppm to 13000 ppm. The local bacteria community has been studied using conventional cultivation method along with modern method of bioindication – a biochip. The low density biochip contains the relevant probes for the ide...

Thermochimica Acta, 2006

The present study examined the cytotoxic effect of increasing Cr(VI) concentrations on cultured c... more The present study examined the cytotoxic effect of increasing Cr(VI) concentrations on cultured cells by a combination of biochemical methods and DSC, a novel use of DSC in the study of cell death. The characteristics of apoptotic cells are compared with normal cells. Chromatin in human epithelial-like L-41 cells has two thermal transitions at 100 and 105 • C. The heat from these endotherms is 90.5 ± 11.0 J/g DNA. The total heat of denaturation (Q d) is 27.5 ± 3.5 J/g dry biomass. The heat evolved (−Q) is 15.6 ± 3.0 J/g dry biomass. The treatment of cells with 20 M Cr(VI) for 2 and 4 h has not revealed any changes in heat of denaturation and heat evolution (−Q). However increased treatment time with Cr(VI) at 20 M resulted in significant changes to the thermal profile and a sharp linear decrease of (−Q) and Q d values. The Q d and (−Q) values of cells treated with 20 M Cr(VI) for 48 h are equal to 15.5 ± 2.0 and 2.1 ± 0.4 J/g dry biomass, respectively. The changes in chromatin conformation, Bax expression and the collapse of the mitochondrial membrane permeability coincide with the time point from which the action of chromium is irreversible.

Biomedical Chromatography, 2000

Colonic tumour cells possess a cell surface protease capable of binding 9-aminoacridine to its ac... more Colonic tumour cells possess a cell surface protease capable of binding 9-aminoacridine to its active centre, thus locating cells when viewed under a fluorescence microscope. In vivo and in frozen sections, the enzyme is masked by a protein inhibitor. This inhibitor can be displaced by formaldehyde fixation of the tissue and then replaced by adding a fresh extract of colon or lung tissue. The inhibitor is modified by oxidation; provided by air, oxidized glutathione or potassium permanganate, resulting in a change in conformation in the inhibitor and this then results in the enzyme binding the fluorescent probe. The effect of oxidation can be reversed by dithiothreitol. It is proposed that these changes are brought about by a disulphide exchange acting on the inhibitor which indirectly controls the activity of the cell surface enzyme in vivo.

Macromolecular Chemistry and Physics, 1997

... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Kats... more ... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Katsarava. Article first published online: 12 MAR 2003. ... Institute of Molecular Biology and Biophysics of Georgian Academy of Sciences, PO Box 24, 380079 Tbilisi-79, Republic of Georgia. ...

Macromolecular Chemistry and Physics, 1997

... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Kats... more ... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Katsarava. Article first published online: 12 MAR 2003. ... Institute of Molecular Biology and Biophysics of Georgian Academy of Sciences, PO Box 24, 380079 Tbilisi-79, Republic of Georgia. ...

Biological Trace Element Research, 2010

The changes in glutathione-dependent cycle enzymes and catalase activities under Cr(VI)-induced o... more The changes in glutathione-dependent cycle enzymes and catalase activities under Cr(VI)-induced oxidative stress were investigated in two distinct cell lines: L-41−human epithelial-like cells and HLF−fetal human diploid lung fibroblasts, which differ in tissue origin, proliferation, and antioxidant enzymes activities. The chromium concentrations from 1 to 5 μM cause nontoxic effects and activate antioxidant enzymes to overcome oxidative stress. In spite of some differences in the endogenous antioxidant activities, both cell lines reveal the same range of toxic concentrations (20-30 μM). The irreversible inhibition of glutathione-dependent antioxidant enzymes develops under toxic concentrations and serves as a marker of toxicity. The endogenous antioxidant activity influences time-dependent expression of Cr(VI) toxicity and the dynamics of antioxidant enzymes activity under nontoxic conditions. The cell antioxidant defense system is an important marker of the cell adaptive capacity under nontoxic and toxic conditions.

Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, 2014

Ischemic stroke (IS) outcome predictors include clinical features, biochemical parameters and som... more Ischemic stroke (IS) outcome predictors include clinical features, biochemical parameters and some risk factors. The relations between two main players in the ischemic brain, MMPs and HMGB1, were estimated in plasma of ischemic stroke patients stratified according to the Glasgow Outcome Scale and the Oxfordshire Community Stroke Project classification. IS patients exhibited higher plasma concentration of MMP-9 and the inflammatory cytokine HMGB1 compared with healthy controls. A full-blown correlation between MMP-9 activation and increased plasma MMP-9 concentration was observed in case of IS patients. A similar activity of MMP-2 and MMP-12 was characteristic of healthy volunteers and IS patients. In patients with ischemic stroke increased plasma levels of MMP-9 and HMGB1 are associated with a poor functional outcome and are significantly correlated with each other (P=0.0054). We suggest that diagnostic benefits will be obtained if plasma HMGB1 levels are measured for IS patients in addition to MMP-9.

Macromolecular Chemistry and Physics, 1996

The feasibility of synthesizing high-molecular-weight amino acid based bioanalogous polymers (AAB... more The feasibility of synthesizing high-molecular-weight amino acid based bioanalogous polymers (AABBPs)-poly(urethane amide)s (PUA)-via polycondensation (PC) of dip-nitrophenyl ester of N,~-(trimethylenedioxydicarbonyl)bis(L-phenylalanine) (3) with diamines or their derivatives under mild conditions in organic solvents was studied for the first time. A regular PUA (q,,,, = 1,53 dL/g) was obtained by PC of 3 with hexamethylenediamine. A dipeptide (Phe-Phe) containing regular poly(ester urethane amide) (q,,,, = 0,58 dL/g) was synthesized by PC of 3 with p-toluenesulfonic acid salt of bis(L-phenylalanine) 1,4-butylene diester. A tripeptide (Phe-Lys-Phe) containing PUA (qred = 0,38 dL/g) with pendent ester groups was prepared via PC of 3 with N,N-bis(trimethylsily1)-L-lysine methyl ester. These novel AABBPs which may be considered as structural analogs of AB type bioanalogous polymersconventional poly(amino acids) are of interest in enzymology, immunology, pharmacology, and biotechnology (as materials for biomedical applications).

Macromolecular …, 1997

... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Kats... more ... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Katsarava. Article first published online: 12 MAR 2003. ... Institute of Molecular Biology and Biophysics of Georgian Academy of Sciences, PO Box 24, 380079 Tbilisi-79, Republic of Georgia. ...

A critical step in biochip design is the selection of probes with identical hybridisation charact... more A critical step in biochip design is the selection of probes with identical hybridisation characteristics. In this article we describe a novel method for evaluating DNA hybridisation probes, allowing the fine-tuning of biochips, that uses cassettes with multiple probes. Each cassette contains probes in equimolar proportions so that their hybridisation performance can be assessed in a single reaction. The model used to demonstrate this method was a series of probes developed to detect TORCH pathogens. DNA probes were designed for Toxoplasma gondii, Chlamidia trachomatis, Rubella, Cytomegalovirus, and Herpes virus and these were used to construct the DNA cassettes. Five cassettes were constructed to detect TORCH pathogens using a variety of genes coding for membrane proteins, viral matrix protein, an early expressed viral protein, viral DNA polymerase and the repetitive gene B1 of Toxoplasma gondii. All of these probes, except that for the B1 gene, exhibited similar profiles under the...

European Heart Journal Supplements, Aug 1, 2020

European Heart Journal Supplements, 2020

Hypertension (HTN) is highly prevalent and the leading cardiovascular risk factor for death globa... more Hypertension (HTN) is highly prevalent and the leading cardiovascular risk factor for death globally. A large proportion of individuals with high blood pressure (BP) are unaware leading to under treatment and poor control. To address this, the International Society of Hypertension (ISH) initiated a global mass screening campaign, the May Measurement Month 2017 (MMM17), in which Kenya participated. Following the success of the campaign, its successor MMM18 was launched. Here, we present the Kenyan results for MMM18. Opportunistic screening of consenting adults was done in various sites across Kenya in May 2018, by volunteers trained using ISH material, under the co-ordination of the Kenya Cardiac Society. Blood pressure, pulse rate, weight, and height were measured by standard methods. Definitions of HTN and statistical methods all adhered to the standard MMM protocol. We screened 49 548 subjects, mean age 39.95 (15.3) years. In total, 49.4% had never had a BP measurement taken. Afte...

Toxics

The dose-dependent effects of single metals (Zn, Ni, and Cu) and their combinations at steady tim... more The dose-dependent effects of single metals (Zn, Ni, and Cu) and their combinations at steady time-actions on the cell viability of the bacteria Shewanella xiamenensis DCB 2-1, isolated from a radionuclide-contaminated area, have been estimated. The accumulation of metals by Shewanella xiamenensis DCB 2-1 in single and multi-metal systems was assessed using the inductively coupled plasma atomic emission spectroscopy. To estimate the response of the bacteria’s antioxidant defense system, doses of 20 and 50 mg/L of single studied metals and 20 mg/L of each metal in their combinations (non-toxic doses, determined by the colony-forming viability assay) were used. Emphasis was given to catalase and superoxide dismutase since they form the primary line of defense against heavy metal action and their regulatory circuit of activity is crucial. The effect of metal ions on total thiol content, an indicator of cellular redox homeostasis, in bacterial cells was evaluated. Genome sequencing of S...

Environmental Sciences

Polyhydroxyalkanoates (PHAs) are biopolymers produced by numerous bacteria and can be used in the... more Polyhydroxyalkanoates (PHAs) are biopolymers produced by numerous bacteria and can be used in the production of bioplastics. PHAs are synthesized by microorganisms by fermentation of carbon sources. Due to the different monomer structures of PHAs, there are many kinds of PHAs, and their corresponding material properties are also very different. Thus, the search for bacteria producing the PHAs is of great interest. In this study, the bacteria isolated from the environment were analyzed for the presence of PHA. PHA production was tested with staining methods Sudan Black B, Nile Blue, and Nile Red. The presence of a PHA synthase gene (phaC) was confirmed by PCR amplification. PHAs were extracted from the strains and characterized by the FTIR spectroscopy method. A biochip for a fast screening of environmental samples for the presence of PHA-producing bacteria was designed. The biochip contained 11 probes for coding class 1, 2, and 3 PHA synthase genes.

The Scientific World JOURNAL, 2003

This is the first of a series of calorimetric studies designed to characterize and understand sur... more This is the first of a series of calorimetric studies designed to characterize and understand survival mechanisms of metal-reducing bacteria isolated from metal-polluted environments. In this paper we introduce a new concept of thermal spectrum of the endothermic melting ofcomplex biological systems (e.g., proteins, nucleic acids, ribosomes, membrane structures)in intact cells. Allthermal spectra measured are thermograms that describe the temperature dependence of heat capacity change of the complex systems of biologically active substances in bacterial cells. This new concept of thermal spectrum was applied to investigate spectral features from intact cells of Cr(VI)-reducer Arthrobacter oxydans at different points of their growth conditions and stages. Over the temperature range of 40–105°C, we observed that spectral changes are particularly significant in the 40–90°C interval. This may correspond to the orderly changes in subcellular structural elements: proteins, ribosomes and R...

Current Microbiology, 2004

Arthrobacter species is of interest because of its high potential for bioremediation. Bacteria ca... more Arthrobacter species is of interest because of its high potential for bioremediation. Bacteria can detoxify chromium, by either reduction or accumulation inside the bacteria and/or absorption of chromium(VI) (CrVI) on their surface, and efflux pump. The possible pathway of Cr(VI) reduction by Arthrobacter oxydans isolated from Columbia basalt rocks at a US DOE highly contaminated site (USA) has been considered in the present study. FTIR absorption spectroscopy showed that these bacteria reduce Cr(VI). In the present study the threshold Cr(VI) nontoxic concentration (35 g/mL) for A. oxydans growing in liquid medium was estimated. Complete uptake of this concentration was achieved in about 10 days after chromium addition into the medium. At this concentration an increase in the protein isolated from the cell wall of A. oxydans was observed. This increased protein predominated independently of the growth phase at which Cr(VI) was added. Thermal analysis was used to identify any influence of Cr(VI) on the DNP complex of A. oxydans. According to the data obtained it can be supposed that Cr(VI) reduction predominantly occurs on the bacterial surface and that cell wall represents a permeable barrier for these bacteria at the non-toxic chromium action.

The Scientific World JOURNAL, 2004

In the present study, the antioxidant capacity of chromium-treated L-41 (human epithelial-like ce... more In the present study, the antioxidant capacity of chromium-treated L-41 (human epithelial-like cells) was investigated by the ESR spin-trapping technique. The crude cell extracts of the cells grown in the presence of 2 µM (nontoxic) and 20 µM (toxic) chromium (VI) concentrations were tested in the model Fenton system with and without catalase-inhibitor sodium azide. The presented approach using the ESR technique along with inhibitors lets us discern cell extract defense capacity connected with the enzymatic activity in viable cells and the catabolic activity in dying cells.

Journal of Inorganic Biochemistry, 2004

In order to investigate the low-dose long-term Cr(VI) action on antioxidant enzymes in cultured m... more In order to investigate the low-dose long-term Cr(VI) action on antioxidant enzymes in cultured mammalian cells we estimated the activity of glutathione dependent antioxidant enzymes, catalase and superoxide dismutase (SOD) under various chromium concentrations in human epithelial-like L-41 cells. The long-term action of 20 lM causes the toxicity that results in losing of the cell viability by activating the apoptotic process, as identified by morphological analysis, the activation of caspase-3, and DNA fragmentation. The toxic chromium concentration totally destroys glutathione antioxidant system, and diminishes the activity of catalase and cytosolic Cu, ZnSOD. The non-toxic concentration (2 lM) causes the activation of the antioxidant defense systems, and they neutralize the oxidative impact.

Biosensors, 2021

Allergenicity assessment of transgenic plants and foods is important for food safety, labeling re... more Allergenicity assessment of transgenic plants and foods is important for food safety, labeling regulations, and health protection. The aim of this study was to develop an effective multi-allergen diagnostic approach for transgenic soybean assessment. For this purpose, multiplex polymerase chain reaction (PCR) coupled with DNA chip technology was employed. The study was focused on the herbicide-resistant Roundup Ready soya (RRS) using a set of certified reference materials consisting of 0, 0.1%, 0.5%, and 10% RRS. Technically, the procedure included design of PCR primers and probes; genomic DNA extraction; development of uniplex and multiplex PCR systems; DNA analysis by agarose gel electrophoresis; microarray development, hybridization, and scanning. The use of the asymmetric multiplex PCR method is shown to be very efficient for DNA hybridization with biochip probes. We demonstrate that newly developed fourplex PCR methods coupled with DNA-biochips enable simultaneous identificatio...

Arsenic [Working Title], 2021

The study is devoted to a very urgent and acute problem for Georgia – remediation/restoration of ... more The study is devoted to a very urgent and acute problem for Georgia – remediation/restoration of the arsenic (As) mining and storage sites. The approach of a given work is based on using capabilities of nature itself, which has a great adaptive potential to chemical environmental pollution. The aim of the study is to identify the bacterial strains from the endemic soil microbiota, characteristic to a specific localization of arsenic contaminated sites and able to resist to the toxicant. To determine the level of arsenic contamination, soil samples have been analyzed using Inductively Coupled Plasma - Optical Emission Spectrometry method. The distribution of arsenic in soil samples splits them into categories according to the degree of contamination, ranging from 50 ppm to 13000 ppm. The local bacteria community has been studied using conventional cultivation method along with modern method of bioindication – a biochip. The low density biochip contains the relevant probes for the ide...

Thermochimica Acta, 2006

The present study examined the cytotoxic effect of increasing Cr(VI) concentrations on cultured c... more The present study examined the cytotoxic effect of increasing Cr(VI) concentrations on cultured cells by a combination of biochemical methods and DSC, a novel use of DSC in the study of cell death. The characteristics of apoptotic cells are compared with normal cells. Chromatin in human epithelial-like L-41 cells has two thermal transitions at 100 and 105 • C. The heat from these endotherms is 90.5 ± 11.0 J/g DNA. The total heat of denaturation (Q d) is 27.5 ± 3.5 J/g dry biomass. The heat evolved (−Q) is 15.6 ± 3.0 J/g dry biomass. The treatment of cells with 20 M Cr(VI) for 2 and 4 h has not revealed any changes in heat of denaturation and heat evolution (−Q). However increased treatment time with Cr(VI) at 20 M resulted in significant changes to the thermal profile and a sharp linear decrease of (−Q) and Q d values. The Q d and (−Q) values of cells treated with 20 M Cr(VI) for 48 h are equal to 15.5 ± 2.0 and 2.1 ± 0.4 J/g dry biomass, respectively. The changes in chromatin conformation, Bax expression and the collapse of the mitochondrial membrane permeability coincide with the time point from which the action of chromium is irreversible.

Biomedical Chromatography, 2000

Colonic tumour cells possess a cell surface protease capable of binding 9-aminoacridine to its ac... more Colonic tumour cells possess a cell surface protease capable of binding 9-aminoacridine to its active centre, thus locating cells when viewed under a fluorescence microscope. In vivo and in frozen sections, the enzyme is masked by a protein inhibitor. This inhibitor can be displaced by formaldehyde fixation of the tissue and then replaced by adding a fresh extract of colon or lung tissue. The inhibitor is modified by oxidation; provided by air, oxidized glutathione or potassium permanganate, resulting in a change in conformation in the inhibitor and this then results in the enzyme binding the fluorescent probe. The effect of oxidation can be reversed by dithiothreitol. It is proposed that these changes are brought about by a disulphide exchange acting on the inhibitor which indirectly controls the activity of the cell surface enzyme in vivo.

Macromolecular Chemistry and Physics, 1997

... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Kats... more ... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Katsarava. Article first published online: 12 MAR 2003. ... Institute of Molecular Biology and Biophysics of Georgian Academy of Sciences, PO Box 24, 380079 Tbilisi-79, Republic of Georgia. ...

Macromolecular Chemistry and Physics, 1997

... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Kats... more ... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Katsarava. Article first published online: 12 MAR 2003. ... Institute of Molecular Biology and Biophysics of Georgian Academy of Sciences, PO Box 24, 380079 Tbilisi-79, Republic of Georgia. ...

Biological Trace Element Research, 2010

The changes in glutathione-dependent cycle enzymes and catalase activities under Cr(VI)-induced o... more The changes in glutathione-dependent cycle enzymes and catalase activities under Cr(VI)-induced oxidative stress were investigated in two distinct cell lines: L-41−human epithelial-like cells and HLF−fetal human diploid lung fibroblasts, which differ in tissue origin, proliferation, and antioxidant enzymes activities. The chromium concentrations from 1 to 5 μM cause nontoxic effects and activate antioxidant enzymes to overcome oxidative stress. In spite of some differences in the endogenous antioxidant activities, both cell lines reveal the same range of toxic concentrations (20-30 μM). The irreversible inhibition of glutathione-dependent antioxidant enzymes develops under toxic concentrations and serves as a marker of toxicity. The endogenous antioxidant activity influences time-dependent expression of Cr(VI) toxicity and the dynamics of antioxidant enzymes activity under nontoxic conditions. The cell antioxidant defense system is an important marker of the cell adaptive capacity under nontoxic and toxic conditions.

Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, 2014

Ischemic stroke (IS) outcome predictors include clinical features, biochemical parameters and som... more Ischemic stroke (IS) outcome predictors include clinical features, biochemical parameters and some risk factors. The relations between two main players in the ischemic brain, MMPs and HMGB1, were estimated in plasma of ischemic stroke patients stratified according to the Glasgow Outcome Scale and the Oxfordshire Community Stroke Project classification. IS patients exhibited higher plasma concentration of MMP-9 and the inflammatory cytokine HMGB1 compared with healthy controls. A full-blown correlation between MMP-9 activation and increased plasma MMP-9 concentration was observed in case of IS patients. A similar activity of MMP-2 and MMP-12 was characteristic of healthy volunteers and IS patients. In patients with ischemic stroke increased plasma levels of MMP-9 and HMGB1 are associated with a poor functional outcome and are significantly correlated with each other (P=0.0054). We suggest that diagnostic benefits will be obtained if plasma HMGB1 levels are measured for IS patients in addition to MMP-9.

Macromolecular Chemistry and Physics, 1996

The feasibility of synthesizing high-molecular-weight amino acid based bioanalogous polymers (AAB... more The feasibility of synthesizing high-molecular-weight amino acid based bioanalogous polymers (AABBPs)-poly(urethane amide)s (PUA)-via polycondensation (PC) of dip-nitrophenyl ester of N,~-(trimethylenedioxydicarbonyl)bis(L-phenylalanine) (3) with diamines or their derivatives under mild conditions in organic solvents was studied for the first time. A regular PUA (q,,,, = 1,53 dL/g) was obtained by PC of 3 with hexamethylenediamine. A dipeptide (Phe-Phe) containing regular poly(ester urethane amide) (q,,,, = 0,58 dL/g) was synthesized by PC of 3 with p-toluenesulfonic acid salt of bis(L-phenylalanine) 1,4-butylene diester. A tripeptide (Phe-Lys-Phe) containing PUA (qred = 0,38 dL/g) with pendent ester groups was prepared via PC of 3 with N,N-bis(trimethylsily1)-L-lysine methyl ester. These novel AABBPs which may be considered as structural analogs of AB type bioanalogous polymersconventional poly(amino acids) are of interest in enzymology, immunology, pharmacology, and biotechnology (as materials for biomedical applications).

Macromolecular …, 1997

... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Kats... more ... Tamara Kartvelishvili,; George Tsitlanadze,; Lamara Edilashvili,; Nona Japaridze,; Ramaz Katsarava. Article first published online: 12 MAR 2003. ... Institute of Molecular Biology and Biophysics of Georgian Academy of Sciences, PO Box 24, 380079 Tbilisi-79, Republic of Georgia. ...

A critical step in biochip design is the selection of probes with identical hybridisation charact... more A critical step in biochip design is the selection of probes with identical hybridisation characteristics. In this article we describe a novel method for evaluating DNA hybridisation probes, allowing the fine-tuning of biochips, that uses cassettes with multiple probes. Each cassette contains probes in equimolar proportions so that their hybridisation performance can be assessed in a single reaction. The model used to demonstrate this method was a series of probes developed to detect TORCH pathogens. DNA probes were designed for Toxoplasma gondii, Chlamidia trachomatis, Rubella, Cytomegalovirus, and Herpes virus and these were used to construct the DNA cassettes. Five cassettes were constructed to detect TORCH pathogens using a variety of genes coding for membrane proteins, viral matrix protein, an early expressed viral protein, viral DNA polymerase and the repetitive gene B1 of Toxoplasma gondii. All of these probes, except that for the B1 gene, exhibited similar profiles under the...