[Olfactory impairment in patients of the older age group with COVID-19 in the acute period and in the period of convalescence.].

Complete or partial loss of sense of smell significantly reduces the quality of life and in some cases is life-threatening. A new coronavirus infection in some cases leads to hypo- or anosmia. The defeat of the olfactory epithelium, swelling of the mucous membrane, the presence of discharge in the nasal cavity complicate the effect of odorants on the neuroepithelium.

[Halitosis. Multidisciplinary approach].

Halitosis is a common complaint among patients. Up to 50% of people worldwide claim to have persistent or intermittent bad breath. Often, bad breath not only disrupts the social life of patients, but is also a symptom of systemic diseases.

[Aging nose (presbinasalis) in the practice of an otorhinolaryngologist.].

Population aging, increasing in duration of active life dictate to keep the level of health and create conditions for prolongation and preservation of ability to work. An otorhinolaryngologist often has to deal with age-related changes occurring in the nasal cavity and paranasal sinuses. The study of age-related features occurring in the nasal cavity and paranasal sinuses at the level of not only function, but also structures providing maintenance of mucous membrane protective mechanisms, preserving nasal architectonics, becomes a topical issue.

[Medicinal products in the treatment and prevention of occupational diseases of the upper respiratory tract].

Occupational diseases of the upper respiratory tract (URT) represent a significant section of occupational pathology of the respiratory system, since the mucous membrane of the nasal cavity and paranasal sinuses is the outpost that first comes into contact with inhaled agents (pollutants), including professional aerosols. The pathogenesis of occupational diseases of URT is based on long-term contact of pollutants with cells of the scintillating epithelium and violation of the function of the mucociliary system of URT. Occupational diseases of URT include: chronic catarrhal, subatrophic, atrophic, hypertrophic rhinitis, rhinopharyngolaryngitis; all forms of laryngitis, laryngotracheobronchitis, allergic diseases.

[Local cytokine therapy of inflammation of the rhinosinusotubal area].

The objective of the present work was to elaborate a scheme for the effective combined treatment ofinflammation of the rhinosinusotubal area including the local administration of roncoleukin and cyclopheron without antibiotics. The study included 82 patients (27 men and 55 women) at the age from 25 to 55 years presenting with acute inflammation ofroncoleukin and cycloferon. They were divided into two groups.

[The rationale for the conservative treatment of chronic tonsillitis in the patients of the older age groups by the «soft» therapy methods].

The objective of the present study was to develop an efficient system for the treatment of chronic tonsillitis in the patients of advanced and middle age based on the application of polyvalent bacteriophages in the combination with the physical factors and herbal medicines. The study involved 65 patients (39 women and 276 men) at the age from 65 to 73 years presenting with chronic tonsillitis. The treatment included washing the tonsillar lacunae with herbal infusion consisting of a tetterwort (Choledoniummajus) extract.

[Tonsillitis and tonsillogenic conditions].

The objective of the present study was to analyze and summarize the literature publications concerning tonsillitis and related (tonsillogenic) pathological conditions. The retrospective analysis of these materials made it possible to collect and summarize information about the influence of palatine tonsillar pathology (chronic tonsillitis) on the function of various organs and their systems. It has been shown that pathogenesis of a great variety of disease is underlain by pathology of palatine tonsils.

[Basic principles of immunocorrective therapy in otorhinolaryngology].

The structural and functional basis of ENT mucosa immunity, leading methods of local immunity assessment in ENT pathology are presented. The experience of the chair and clinic of I.P.

A comparative study of functional properties of calf chymosin and its recombinant forms.

The action of calf chymosin obtained from transgenic sheep milk and the recombinant protein expressed in yeast Kluyveromyces lactis (Maxiren) on fluorogenic peptide substrates, namely Abz-A-A-F-F-A-A-Ded, Abz-A-A-F-F-A-A-pNA, Abz-A-F-F-A-A-Ded, Abz-A-A-F-F-A-Ded, Abz-A-A-F-F-Ded, Abz-A-A-F-F-pNA, and heptapeptide L-S-F-M-A-I-P-NH2, a fragment of kappa-casein (the native chymosin substrate), was investigated. It has been established that transgenic chymosin and recombinant chymosin (Maxiren) differ from the native enzyme in their action on low molecular weight substrates, whereas there was no difference in enzymatic action on protein substrates. Pepstatin, a specific inhibitor of aspartic proteinases, inhibits the recombinant chymosin forms less efficiently than the native enzyme.

[Peculiarities of immune responses during general anesthesia in otosurgery].

Immune responses were investigated in 118 patients suffering from chronic purulent inflammation of middle ear. All of them were operated under different methods of anesthesia. Immunotherapy preceding intravenous anesthesia with combination of phentanyl and clophelline along with supporting spontaneous breathing was found to be the most optimal from the immunologic point of view.

Isolation of milk-clotting enzyme from transgenic sheep milk and its comparison with calf chymosin.

Technology for preparation of chymosin from milk of transgenic sheep has been elaborated. Purification of the preparation by ion-exchange chromatography on aminosilochrom and biospecific chromatography on bacitracin-Sepharose yielded homogeneous active enzyme. Hydrolysis of protein substrates (hemoglobin, BSA, and sodium caseinate) by the transgenic sheep chymosin and stability of the enzyme at various values of pH were studied.

Fluorogenic substrates for assay of chymosin.

The use of fluorogenic substrates with intramolecular fluorescence quenching as substrates for chymosin was studied. It was shown that chymosin hydrolyzes the Phe-Phe peptide bond. The effect of pH on the hydrolysis of substrates by chymosin was investigated.

[A study of aspartyl proteases using intramolecularly quenched fluorogenic peptide substrates].

A series of fluorogenic tetra-, penta-, and hexapeptide substrates of the general structure Abz-X-Phe-Phe-Y-Ded (or -pNa in place of -Ded), where X = Ala, Ala-Ala, or Val-Ala and Y = -, Ala, or Ala-Ala, were proposed. Kinetic parameters of hydrolysis of these substrates by pepsin, cathepsin D, human gastricsin, pig pepsin, calf chymosin, and aspergillopepsin A were determined. The compounds synthesized proved to be effective substrates for aspartyl proteases of diverse origins.

Buffalo (Bos buffali L.) chymosin purification and properties.

Buffalo chymosin was isolated from abomasum mucosa extract of buffalo calves by affinity chromatography on gramicidin S-agarose followed by ion exchange chromatography on gamma-aminopropylsilochrom. Its molecular weight, 36 +/- 1 kDa, is similar to that of bovine calf chymosin. The N-terminal sequence Gly-Glu-Val-Ala-Ser-Val-Pro- coincides with that of bovine enzyme, whereas some differences were found in the amino acid composition of these enzymes.

[Co-precipitation of pepsin with products from the enzymatic synthesis of peptides as a factor limiting the effectiveness of the enzyme].

Porcine pepsin behaviour during the synthesis of peptide p-nitroanilides and esters has been studied. In many cases, especially when long-chain peptides, such as Z-Ala-Ala-Phe-Leu-Ala-Ala-OMe, were synthesized, pepsin disappeared from the solution, being entrapped by the product precipitate rather than inactivated. Sorption of the enzyme on the product might be partially responsible for this effect.

Synthesis of tetrapeptide p-nitroanilides catalyzed by pepsin.

Swine pepsin at pH 5 efficiently catalyzes a condensation between Z-Ala-Ala-Phe-OH and p-nitroanilides of Leu, Phe, Val, Ala and Arg that leads to formation of corresponding benzyloxycarbonyl-tetrapeptide p-nitroanilides with yields of 70-90%. These reactions are complicated by co-precipitation of pepsin and the reaction products that necessitates the use of a relatively high concentration of pepsin.

[Pepsin in the enzymatic synthesis of esters and n-nitroanilide peptides].

Pepsin was shown to catalyze synthesis of esters or p-nitroanilides tri-, tetra-, penta- and hexapeptides of general formula Z-X-Y-B, where X = Ala-Phe, Phe-Met, Ala-Ala-Glu, Ala-Ala-Phe, Ala-Ala-Leu, Ala-Ala-Trp, Ala-Ala-Met. Y = Ala, Leu, Val, Phe, Arg, Ala-Ala, Gly-Gly, Leu-Ala-Ala, Phe-Ala-Ala. B = OMe, pNA.

Pepsin as a catalyst of peptide synthesis. Enzyme co-precipitation with emerging peptide products.

Pepsin successfully catalyzed the synthesis of several peptide derivatives from N-protected di- or tripeptides and amino acid or peptide esters or p-nitroanilides in dimethylformamide-water solutions at pH 4.6. An optimal substrates:pepsin ratio depended on the structure of starting peptides, especially their fit to the substrate binding sites of the enzyme.

[Limited proteolysis of human albumin and immunoglobulin G by Legionella pneumophila metalloproteinase].

Metalloproteinase of Legionella pneumophila is the major extracellular proteinase of this bacterial species which splits human immunoglobulin G in the hinge region to form the (Fab')2 fragment. This fragment is relatively stable and undergoes further proteolysis at a slow rate. The c' fragment is unstable and is apparently split down to fragments CH2 and CH3.

[The effect of Legionella pneumophila metalloproteinase on certain human blood proteins. Cleavage of anti(1)-antitrypsin and acid-stable serine proteinase inhibitors].

Antitryptic activity of human blood serum was decreased after incubation with metalloproteinase from Legionella pneumophila. The enzymatic activity depends on the time of incubation as well as on the ratio between the enzyme content and blood serum total protein. Cross immunoelectrophoresis, involving monospecific rabbit antiserum towards the alpha 1-antitrypsin, demonstrated highly effective hydrolysis of alpha 1-antitrypsin by the metalloproteinase.

Pepsin behavior as a catalyst in equilibrium-controlled peptide synthesis.

It has been shown that in the course of equilibrium peptide synthesis pepsin gradually disappeared from the liquid phase due to its entrapment within a gel formed by the hexapeptide product, while retaining its activity. The inclusion into the precipitate was not specific for pepsin so far as inert proteins-lysozyme, ribonuclease A and carbonic anhydrase, when added to the reaction mixture, became also co-precipitated with the hexapeptide formed. It appears that co-precipitation of pepsin-an important factor limiting the enzyme efficiency, might be operative as well for other proteinases used to catalyze peptide synthesis.

Chymosin-catalyzed peptide synthesis.

Calf chymosin catalyzes peptide synthesis optimally at pH 4-5 giving satisfactory yields of methyl esters or p-nitroanilides of benzyloxycarbonyl tetra- to hexapeptides, provided that hydrophobic amino acid residues form the new peptide bond. The enzyme efficiency depends also on the nature of adjacent amino acid residues. As an aspartyl proteinase with characteristic specificity pattern chymosin would be useful for synthesis of middle length peptides.