[Drug-induced uveitis]. / Lekarstvenno-indutsirovannyi uveit.

In recent years, an increasing amount of attention has been paid to medicinal products as possible risk factors in the development of eye diseases. The frequency of diagnosed drug-induced uveitis is growing yearly, which can be attributed to the appearance of new drugs - biological agents (immune checkpoint inhibitors, BRAF and MEK inhibitors, vascular endothelial growth factor inhibitors, tumor necrosis factor-α inhibitors), as well as systemic bisphosphonates and some antiviral drugs. The time interval between the beginning of the drug use and the appearance of uveitis symptoms varies from several days to months. Common symptoms include eye pain, photophobia, the appearance of floating opacities, and reduced vision associated with active inflammatory changes in the retina and optic nerve and outcomes of those inflammations. Timely diagnosis, cancellation of the drug that caused uveitis and appointment of adequate anti-inflammatory therapy in most cases effectively stops the symptoms of the disease, which determines the relevance of attention to the prevalence, pathogenesis, diagnosis and treatment of drug-induced uveitis.

[Rhinitis medicamentosa]. / Lekarstvenno-indutsirovannyi rinit.

One type of non-allergic non-infectious rhinitis is represented by a heterogeneous group of rhinitis medicamentosa, which can be divided into several pathogenetic types. The most common rebound nasal congestion associated with the use of topical decongestants. Excessive use of intranasal decongestants leads to a decrease in the number of alpha-adrenoreceptors on the surface of cell membranes and uncoupling their connection with the G-protein and the development of tachyphylaxis. To prevent the development of rebound nasal congestion caused by topical decongestants, it is important to limit the frequency of their use. In most cases, the duration of the use of vasoconstrictor drugs should be limited to 5-7 days, according to Patient information leaflets for the drugs. However, in patients who have had a history of episodes of rebound nasal congestion, which develops including the previously indicated periods, the duration of decongestant therapy should be limited to 3 days. Rhinitis associated with local inflammation is caused by the intake of acetylsalicylic acid (ASA) or other non-steroidal anti-inflammatory drugs. Currently, the so-called "aspirin triad" is well known - a combination of bronchial asthma, rhinosinusitis (often polyposis) and intolerance to ASA. Neurogenic rhinitis develops due to the use of drugs that violate vascular tone, for example, antihypertensive drugs or type 5 phosphodiesterase inhibitors. Drug-induced rhinitis has a significant impact on the patient's quality of life: nasal congestion, rhinorrhea, secondary night apnea, insomnia as a result of nasal breathing disturbances, headaches, irritability, weakness after sleepless nights disturb patients to a large extent. Timely diagnosis and withdrawal of a provocative drug, the use of topical corticosteroids in case of severe rhinitis are the basis of the treatment of rhinitis medicamentosa. In severe cases, there is a need, including surgical treatment, such as, for example, submucosal laser destruction of the lower nasal concha.

[Drug-induced glaucoma]. / Lekarstvenno-indutsirovannaya glaukoma.

Glaucoma is seen as a heterogeneous group of diseases characterized by optical neuropathy with associated visual field loss; one of the main risk factors for its development is increased intraocular pressure (IOP). In the case of drug-induced glaucoma (DIG), patients develop elevated IOP, optic neuropathy and visual field defects associated with the use of certain drugs. Corticosteroids are one of the most well-known classes of drugs that can cause an increase in IOP through the open-angle mechanism. Drug-induced glaucoma, which develops similarly to open-angle glaucoma, can also be caused by some non-steroidal anti-inflammatory agents, antibodies to the endothelial growth factor, etc. Classes of drugs that can cause angle-closure glaucoma include topical anticholinergic or sympathomimetic drops, tricyclic antidepressants, monoamine oxidase inhibitors, antihistamines, antiparkinsonian drugs, antipsychotic drugs, antispasmodics. Products containing sulfa group drugs can cause DIG due to a different closing angle mechanism involving a forward rotation of the ciliary body. It is important for medical practitioners to be aware of this unwanted drug reaction in order to prevent, detect and treat DIG. In the case of drug-induced increase in IOP, if the underlying disease allows discontinuation of drugs, this measure usually leads to normalization of IOP. In cases when the patient's IOP does not normalize after discontinuation of steroids or when they must continue to take corticosteroids, the administration of topical drugs for the treatment of glaucoma should be considered.

[Drug-induced dysphonia]. / Lekarstvenno-indutsirovannaya disfoniya.

Drug-induced dysphonia is a non-life-threatening adverse drug reaction, however, this complication can significantly worsen the quality of life of patients, especially those in voice-speaking professions. The aim of the work was to search for information about the prevalence, etiology, pathogenesis, and features of treatment and prevention of drug-induced dysphonia. In the case of some drugs, the true prevalence may be higher than described in the literature, due to the fact that dysphonia is in most cases mild, reversible and, in comparison with other undesirable drug reactions, rarely attracts the attention of both the patient and practitioners.

[Drug-induced hearing loss as a manifestation of drug-induced ototoxicity]. / Lekarstvenno-indutsirovannaia tugoukhost' kak proiavlenie lekarstvenno-indutsirovannoi ototoksichnosti.

The ability of drugs to have an ototoxic effect has been studied for a long time, however, the true prevalence of this undesirable phenomenon is unknown, which is due to the use of various audiological protocols, a wide range of reactions to drugs in different ethnic groups, and most importantly, the lack of caution with regard to otological symptoms due to their reversibility or lack of immediate threat to life. Drug-induced ototoxicity is a functional disorder of the inner ear (cochlea and/or vestibular apparatus) or eighth pair of cranial nerves. Pharmacotherapy, associated with the development of ototoxic drug reactions, may remain undervalued for a long time, often until irreversible hearing impairment is formed. The most frequently prescribed drugs that cause ototoxic phenomena include anticancer drugs, antibacterial drugs of the aminoglycoside group, loop diuretics, calcium channel blockers, non-steroidal anti-inflammatory drugs, antimalarial drugs, salicylates, etc. Monitoring the degree of hearing impairment before and during therapy is important in preventing the development of drug-induced ototoxicity and makes it possible to consider alternative treatment regimens in a timely manner. It is in this connection that the role of participation in the appointment of rational pharmacotherapy to patients with a potential risk of developing otological phenomena of a clinical pharmacologist and audiologist undoubtedly increases.

Peculiarities of the Regulation of Gene Expression in the Ecl18kI Restriction-Modification System.

Transcription regulation in bacterial restriction-modification (R-M) systems is an important process, which provides coordinated expression levels of tandem enzymes, DNA methyltransferase (MTase) and restriction endonuclease (RE) protecting cells against penetration of alien DNA. The present study focuses on (cytosine-5)-DNA methyltransferase Ecl18kI (M.Ecl18kI), which is almost identical to DNA methyltransferase SsoII (M.SsoII) in terms of its structure and properties. Each of these enzymes inhibits expression of the intrinsic gene and activates expression of the corresponding RE gene via binding to the regulatory site in the promoter region of these genes. In the present work, complex formation of M.Ecl18kI and RNA polymerase from Escherichia сoli with the promoter regions of the MTase and RE genes is studied. The mechanism of regulation of gene expression in the Ecl18kI R-M system is thoroughly investigated. M.Ecl18kI and RNA polymerase are shown to compete for binding to the promoter region. However, no direct contacts between M.Ecl18kI and RNA polymerase are detected. The properties of M.Ecl18kI and M.SsoII mutants are studied. Amino acid substitutions in the N-terminal region of M.Ecl18kI, which performs the regulatory function, are shown to influence not only M.Ecl18kI capability to interact with the regulatory site and to act as a transcription factor, but also its ability to bind and methylate the substrate DNA. The loss of methylation activity does not prevent MTase from performing its regulatory function and even increases its affinity to the regulatory site. However, the presence of the domain responsible for methylation in the M.Ecl18kI molecule is necessary for M.Ecl18kI to perform its regulatory function.

The study of the interaction of (cytosine-5)-DNA methyltransferase SsoII with DNA by acoustic method.

The interaction of (cytosine-5)-DNA methyltransferase SsoII (M.SsoII) with double-stranded DNA was studied by means of thickness shear mode acoustic method (TSM) and gel electrophoresis. M.SsoII recognizes in double-stranded DNA the methylation site 5'-CCNGG-3' (N=A, C, G, T) and methylates the inner cytosine residue. M.SsoII also acts as a transcription factor via binding to the regulatory site 5'-AGGACAAATTGTCCT-3' in the promoter region of SsoII restriction-modification system. We designed three 60-mer biotinylated DNA duplexes: with the methylation site (60met), with the regulatory site (60reg), and without a specific binding site (60oct). A strong binding of M.SsoII with each one of the studied DNA immobilized on the TSM transducer has been shown. The equilibrium dissociation constants, K(D), of the M.SsoII-DNA complexes decreased in the order 60oct>60reg>60met, suggesting a higher stability of M.SsoII-60met complex in comparison with the others. The association rate constant, k(a), was also higher for 60met, while similar values were obtained for 60reg and 60oct. The difference in the kinetic parameters for 60met and 60reg suggested a possible way of coordination between the two M.SsoII functions in a cell.