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N A Ponomarenko

Publications and source records attributed to N A Ponomarenko.

At least 19 recordsLinked to original sources
PubMed2006

[Catalytic autoantibodies as a new molecular instrument in rheumatological practice].

AIM: To compare clinicopathogenetic value of DNA-hydrolizing autoantibodies or DNA-abzymes in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). MATERIAL AND METHODS: We studied sera from 180 patients with SLE, 180 RA patients and 128 healthy donors matched by age and gender; assessed catalytic and cytotoxic activity of DNA-abzymes in patients with different variants of SLE and RA course. RESULTS: The highest catalytic and cytotoxic activities of DNA abzymes were observed in SLE patients. In SLE catalytic and cytotoxic activities of DNA abzymes ranged widely and their mean values depended on SLE activity in patients with systemic lesions. DNA-abzymes in RA patients showed lower catalytic and cytotoxic activities in relation to substrate DNA and target cells than in SLE. DNA-abzymes occurred most frequently in patients with high activity of RA, slow-progressive and lingering course of RA, especially in early development of visceral (extra-articular) pathology. Characteristic for DNA-abzymes in RA and SLE is the phenomenon of wide-range fluctuations due to factors determinating probability of induction of function of Ab-mediated catalysis and, therefore, incidence rates of DNA-abzymes, probably catalytic autoAb of the other specificity in a population of patients with systemic autoimmune diseases. CONCLUSION: The data indicate the validity of DNA abzymes use in clinical practice for realization of diagnostic and therapeutic programs in SLE and RA.

Adult↗
PubMed2006

[Catalytic autoantibodies--a new molecular instrument in cardiology and ophthalmology].

AIM: To develop a conceptual model of using catalytic autoantibodies as diagnostic and monitoring tools in organ-specific autoimmune disorders. MATERIAL AND METHODS: A total of 99 patients (56 males and 43 females aged 21-52 years) with autoimmune myocarditis (AM) and 198 patients (77 males and 121 females aged 8-79 years) with autoimmune uveitis (A U) participated in the study. AM patients were examined for anticardiomyosin and anti-DNA autoantibodies (ACM, ADNAab), AU patients - for autoantibodies to S-antigen, IRBP, redopsin, phosphocine, autoDNA. RESULTS: AM patients had double level of DNA-binding autoantibodies. In 1/3 of them there was hydrolysing DNA and cytotoxic activity. In AU patients maximal titers were in Behcet's disease, sympathic ophthalmia, generalized uveitis and viral uveitis. CONCLUSION: Autoantibodies with different specificity and function including DNA-abzymes can be additional diagnostic and prognostic markers.

Adolescent↗
PubMed2005

[Achievements and prospects of clinical abzymology].

Catalytic autoantibodies (abzymes) are autoantibodies that are potentially ready to realize certain effects in the organism, first of all antibody-mediated catalysis and cytotoxicity. Natural abzymes with protolytic (protabzymes) and DNA-hydrolyzing DNA-abzymes) activity are of the greatest interest. The most impressive example of the catalytic activity of protabzymes is hydrolysis of specific proteins, revealed in patients with autoimmune diseases, such as bronchial asthma (vasoactive intestinal neuropeptide), autoimmune thyroiditis (thyroglobulin), multiple sclerosis (myelin basic protein), and autoimmune myocarditis (cardiomyosin). The pathogenic role of DNA-abzymes is not quite clear yet. However, it has been proven that they present a powerful regulator of apoptosis and other cytotoxicity mechanisms in systemic autoimmune diseases and tumors. The most promising is use of abzymes as illness activity markers, and as therapeutic agents capable of catalyzing specific proteins or activating antitumoral chemotherapeutic preparations.

Animals↗
PubMed2005

[Catalytic autoantibodies in autoimmune myocarditis: clinical and pathogenetic implications].

AIM: To evaluate pathogenetic and clinical significance of autoantibodies (AAB) with catalytic activity in the serum of patients with autoimmune myocarditis (AM). MATERIAL AND METHODS: The study was made on the sera from 99 patients with AM of different course: malignant, benign, myocardiosclerosis (MCS). In addition to standard immunological parameters, the study was made of serum levels of anticardiomyosine-antiCM (protabzymes) and anti-DNA (DNA-abzymes) of AAB. After obtaining anti-CM and anti-DNA IgG-AT, we determined non-specific and specific proteolytic activity of anti-CM. RESULTS: Maximal specific activity of protabzymes was seen in 73% patients with malignant AM, it correlated with blood levels of anti-CM AAB, DNA-abzymes activity was very high in 45% patients. In MCS proteolytic activity of autoAT was absent in 61% patients. In benign AM occurrence of protabzymes was confirmed in 35% cases. Elevated DNA-hydrolyzing activity of DNA-abzymes occurred in 13% cases. The activity had no significant correlation with serum titers of AB. In MCS proteolytic activity of AAB was absent in 61% cases, but high activity of anti-CM AAB was in 28%. The activity of DNA-abzymes in 44% ranged considerably which, in seropositive cases, detected significant correlation with serum titers of DNA-binding autoAT. CONCLUSION: Evaluation of catalytic activity of AAB may be considered as a criterial test assessing the stage, clinical variants and severity of AM. It also permits formulation of the disease prognosis and its possible outcomes.

Antibodies, Catalytic↗
PubMed2005

[DNA-abzymes in rheumatoid arthritis: pathogenetic and clinical significance].

AIM: To study possible pathogenetic role and clinical significance of DNA-hydrolysing autoantibodies (autoAB) or DNA-abzymes in patients with rheumatoid arthritis. MATERIAL AND METHODS: Prevalence of DNA-abzymes and their catalytic activity were studied in 400 patients with rheumatoid arthritis (RA) and 88 healthy donors matched by age and gender. RESULTS: Associated with DNA-binding autoAB DNA-hydrolysing activity was detected in 41.5% cases of RA. DNA-abzymes were maximally active in men with rheumatoid factor (RF) and women without RF, while it was minimal in men without RF and women with RF. By catalytic activity there was no significant differences between patients with RF and without it. The highest catalytic activity of DNA abzymes was detected in patients with distinct extraarticular pathology. DNA-abzymes were also active in patients with x-ray stage III-IV of the disease in association with high prevalence of catalytic autoAB. DNA abzymes were also active in patients with RA activity stage II and III. CONCLUSION: It is possible to use DNA-abzymes in clinical practice for monitoring of the disease activity in RA.

Antibodies, Catalytic↗
PubMed2002

Antibody proteases: induction of catalytic response.

Most of the data accumulated throughout the years on investigation of catalytic antibodies indicate that their production increases on the background of autoimmune abnormalities. The different approaches to induction of catalytic response toward recombinant gp120 HIV-1 surface protein in mice with various autoimmune pathologies are described. The peptidylphosphonate conjugate containing structural part of gp120 molecule is used for reactive immunization of NZB/NZW F1, MRL, and SJL mice. The specific modification of heavy and light chains of mouse autoantibodies with Val-Ala-Glu-Glu-Glu-Val-PO(OPh)2 reactive peptide was demonstrated. Increased proteolytic activity of polyclonal antibodies in SJL mice encouraged us to investigate the production of antigen-specific catalytic antibodies on the background of induced experimental autoimmune encephalomyelitis (EAE). The immunization of autoimmune-prone mice with the engineered fusions containing the fragments of gp120 and encephalitogenic epitope of myelin basic protein (MBP(89-104)) was made. The proteolytic activity of polyclonal antibodies isolated from the sera of autoimmune mice immunized by the described antigen was shown. Specific immune response of SJL mice to these antigens was characterized. Polyclonal antibodies purified from sera of the immunized animals revealed proteolytic activity. The antiidiotypic approach to raise the specific proteolytic antibody as an "internal image" of protease is described. The "second order" monoclonal antibodies toward subtilisin Carlsberg revealed pronounced proteolytic activity.

Animals↗
PubMed2001

New experimental model of multiple myeloma.

NSO/1 (P3x63Ay 8Ut) and SP20 myeloma cells were inoculated to BALB/c OlaHsd mice. NSO/1 cells allowed adequate stage-by-stage monitoring of tumor development. The adequacy of this model was confirmed in experiments with conventional cytostatics: prospidium and cytarabine caused necrosis of tumor cells and reduced animal mortality.

Animals↗
PubMed1999

[Detection of a new tissue-specific enhancer in the ct6 region of the regulatory region of the drosophila cut locus].

The cut locus of Drosophila is an interesting example of a complex eukaryotic locus responsible for the development of many tissues and organs. Most of this locus is regulatory. The entire locus was cloned by Tchurikov et al. in 1986 and Blochlinger et al. in 1988. The wing ctn enhancer located 80 kb upstream of the promoter was earlier found in a 2.7 kb EcoRI-BamHI DNA fragment. The locus region 65-80 kb remote from the promoter was assumed to control the development of wings and vibrissae. We have found a new enhancer region in the ct6 region of the locus, which was in a 5 kb BamHI-EcoRI DNA fragment adjacent to the ctn enhancer. This region is responsible for the expression of the reporter lacZ gene in many tissues and organs at all stages of Drosophila development (at least in the intestine, Malpighian tubules, thoracic and abdominal sensory organs, thoracic ganglia and in ring glands). Thus, the region located 75 kb upstream of the promoter has some properties of the locus control region (LCR).

Animals↗
PubMed1999

[Localization of transcripts corresponding to different regions of the "cut" locus in Drosophila embryos].

Transcripts of the cut locus were localized in Drosophila embryos with use of nonradioactive in situ hybridization. DIG-labeled probes were generated from two locus regions located at position -130. Distal and proximal regions were found to be transcribed in the same tissues throughout embryogenesis. As only the proximal region transcript was detected, the conclusion was made that two or more various transcripts derived from different regions of the locus and under common control, are present simultaneously in the embryonic cells.

Animals↗
PubMed1998

Forum domain in Drosophila melanogaster cut locus possesses looped domains inside.

We have studied the relationship between chromosomal forum domains and looped domains in the cut locus of Drosophila melanogaster . Forum domains were earlier detected by separation in pulsed-field gels of 50-150 kb chromosomal DNA fragments obtained after spontaneous non-random degradation of chromosomes. We have localized the boundary region where cleavage sites are scattered between two forum domains in the regulatory region of the cut locus. We have sequenced a 13 kb region spanning few kilobases from distal domain, the boundary region and part of the proximal forum domain where several scaffold associated regions (SARs) were observed. We conclude that forum domains and looped domains are physically different types of domains and belong to different levels of organization in eukaryotic chromosomes. The boundary region between the neighboring forum domains in the cut locus possesses the Doc element insertion and a micro-satellite stretch and thus might remind a small island of heterochromatin and correspond to so-called intercalary heterochromatin that is known to be located in the 7B1-2 band where the major part of the cut locus is reside.

Amino Acid Sequence↗
PubMed1997

Burdock, a novel retrotransposon in Drosophila melanogaster, integrates into the coding region of the cut locus.

The burdock element is known to be the 2.6-kb insertion into the same region of the cut locus in 12 independently obtained ct-lethal mutants. Here we have determined the complete sequences of this insertion and of the hot spot region. It was found that the burdock is a short retrotransposon with long terminal repeats and a single open reading frame (ORF). The polypeptide encoded by the burdock ORF contains two adjacent regions homologous to the gag and pol polyproteins of the gypsy mobile element. The burdock insertion interrupts the short ORF of the cut locus. The target site sequence of the burdock insertions is similar to the Drosophila topoisomerase II cleavage site.

Amino Acid Sequence↗
PubMed1997

[Molecular analysis of a copy of the novel mobile element Burdock and the region of its insertion into the cut locus of Drosophila melanogaster].

Molecular analysis of a copy of the novel mobile element burdock and its insertion region into the cut locus of Drosophila was performed. The burdock was shown to be a retrotransposon containing a single open reading frame (ORF). It does not contain domens coding for protease, RNAse H, reverse transcriptase, and integrase, which are required for transposition. However, multiple insertions of this copy of the mobile element into a definite region of the cut locus (hot site) were observed earlier. The polypeptide encoded by the burdock ORF contains two successive regions homologous to the proteins encoded by the ORF1 and ORF2 of the gypsy retrotransposon in N and C regions, respectively. The burdock insertion into this region of the cut locus interrupts its ORF, since the mobile element is transcribed in the opposite direction compared with the transcription in the locus. This is presumed to account for the arising of a lethal mutation. The hot site of this element integration into the locus corresponds to the recognition site of Drosophila topoisomerase II.

Amino Acid Sequence↗
PubMed1996

[Analysis of copies of the suffix-retroposon of Drosophila, produced using PCR on genomic DNA].

Nineteen DNA clones, containing copies of the suffix element retroposon of the Drosophila genome and produced by a polymerase chain reaction (PCR), were sequenced. Insertions of the copies in both orientations into microsatellite sequences (CAACA)n/(TGTTG)n and (TTTGT)n/(CACAAA)n were revealed. It was found that, if the microsatellite sequence has both a decanucleotide GCGGCCCGGG (GC-box) and a colinear alternating sequence (A)5(T)4(A)3(T)2(A)1(t)n (AT-box), the insertion of the suffix occurs in only one orientation. It is suggested, that in such apparently heterochromatic sequences, suffix element copies and probably some other retroposons can be inserted a particular orientation by means of site-specific recombination. An approach to analysis of the molecular organization of such sequences is proposed.

Animals↗
PubMed1995

The formation of parallel RNA-RNA duplexes in vitro.

Over the years the structural properties of nucleic acids have been of interest, providing data that may be of importance for DNA and RNA organization and function in the cell. We have attempted to look for the formation of parallel RNA-RNA duplexes in vitro. RNA molecules comprising complementary in the same polarity alternating stretches of A and U of increasing length were enzymatically synthesized and annealed in physiological conditions. The fractionation in the denaturing polyacrylamide gels revealed the formation of two types of full-length parallel RNase A-stable duplexes established either by A-U or by A-A and U-U self pairs. These results suggest novel structural properties of versatile RNA molecules that potentially may be realized in vivo.

Base Sequence↗