[Analysis of hearing aids application in elderly patients.]

The aim of the study is to evaluate the possibility to implement machine learning to create a digital auditory profile for elderly patients and to analyze the hearing aid fitting efficacy depending on involvement of the peripheral and central auditory pathways in a pathological process. Data analysis of 375 people aged 60-93 years is presented. 355 patients with chronic bilateral hearing loss (230 of them used hearing aids) were included in the main group, and 20 normal hearing elderly people were included in the control group. Audiological examination consisted of standard tests (pure tone audiometry, impedancemetry, speech audiometry in quiet) and tests to evaluate the central auditory processing (binaural fusion, dichotic digits, speech audiometry in noise, random gap detection). The Montreal Cognitive Assessment was used to detect cognitive impairment. The hearing aid fitting efficiency was evaluated with COSI questionnaire and speech audiometry in free field. Processing of the results was carried out using Pearson's correlation analysis aimed at creating a polynomial model of a patient's hearing on the basis of the limited test battery. There were close correlations between the state of cognitive functions and age, results of tests to evaluate the central auditory processing, as well as patients' satisfaction of hearing aid. The results of the work indicate the possibility of using computer technologies of data analysis to develop rehabilitation programs for elderly hearing impaired patients.

[Strategies of hearing aids fitting for improving speech recognition in noisy environments]. / Vozmozhnosti uluchsheniya razborchivosti rechi v shume pri slukhoprotezirovanii.

THE AIM OF THE STUDY: To assess speech recognition in users of mono- and binaural hearing aids (HA) with dynamic environment control system (DECS). MATERIAL AND METHODS: 25 HA users with symmetrical bilateral moderate to severe sensorineural hearing loss and 10 individuals with normal hearing underwent speech audiometry in a free sound field by listening to an adaptive Russian matrix sentence test with a background noise. The testing was conducted for hearing impaired patients with one and two HA. The Speech Recognition Thresholds in noise (SRTN) using HA with DESC and using HA without DESC were compared. The dichotic digits test and the rapidly alternating speech perception test were performed to evaluate the central auditory system function. RESULTS: The SRTN in normal hearing listeners was -16.4±1.9 dB SNR. In the case of monaural using HA without DESC the SRTN was -2.5±4.4 dB SNR, using HA with DESC it was -5.8±4.0 dB SNR; in the case of using binaural HAs it was -6.3±3.8 dB SNR and -9.9±3.1 dB SNR accordingly. CONCLUSIONS: HAs with Dynamic Environment Control System are highly effective for speech perception in noisy environments. Binaural HA use is more effective than monaural HA use regardless of HA model. Speech recognition in noisy environments in cases of binaural HA use correlates significantly with results of tests assessing the central auditory system function.

Possible genetically determined mechanisms of arterial hypertension in tobacco smoking.

Te increase in the prevalence of arterial hypertension (AH) in populations, ineffective treatment, the need for risk stratifcation, prevention, early diagnosis and successful treatment, actualize genomic studies to develop a personalized therapeutic approach to AH. Te review investigates the possible genetically determined mechanisms of the development of hypertension and endothelial dysfunction caused by polymorphism of the genes of endothelial nitric oxide synthase (eNOS) and enzymes of phases I and II of the xenobiotics detoxifcation system. Te probable interaction of both systems under the influence of harmful environmental factors, including tobacco smoking, and in the gestational period is discussed. It is proposed to study AH candidate genes in the xenobiotics detoxifcation system, the carriage of different variants of which can determine the sensitivity or resistance to antihypertensive pharmacotherapy, which can be useful for developing of the personalized tactics of managing patients with AH.

[Optimization of digitalis therapy in clinical practice].

In recent years there has been a marked decrease in cardiac glycosides use in patients with heart failure in sinus rhythm and atrial fibrillation. The results of published studies contradict each other. Some of them doubt the favorable effect of digoxin in patients with heart failure; others refute the increase in the lethality and frequency of hospitalizations associated with the use of digoxin. In this regard, we found it important to analyze these reports impartially and reflect modern views on the mechanisms of cardiac glycosides, the pharmacokinetics and the possibility of optimizing digitalis therapy in cardiac practice.

[Rehabilitation of hearing impaired elderly patients by means of hearing aids with frequency lowering technology.]

The objective of this study was to assess the effectiveness of rehabilitation of hearing impaired elderly patients using hearing aids with frequency lowering technology called Frequency Composition ™. 23 hearing aid users (mean age 64 years) with moderate to severe sensorineural hearing loss were tested. All participants were divided into two groups according to configuration of audiogram: 11 people with averaged slope of 27,9 dB per an octave within frequency range of 1-2 kHz (the 1st group) and 12 people with slope of 24,1 dB at 2-4 kHz (the 2nd group). Average speech tests scores of the 1st group were significantly worse than for the 2nd group (p<0,05 in quiet; p<0,01 in noise). It has been seen that the 1st group had significant better improvement of speech understanding using of Frequency Composition™ than the 2nd group. It has been shown that frequency lowering can improve perception of high frequency sounds and enhance speech intelligibility especially in patients with audiogram slope within frequency range of 1-2 kHz. To effective use of frequency lowering technology a careful selection of patients and adaptation to the new algorithm of amplification are required.

[The speech audiometry using the matrix sentence test]. / Rechevaya audiometriya s ispol'zovaniem matriksnogo frazovogo testa.

The matrix sentence test in which the five-word semantically unpredictable sentences presented under the background noise conditions are used as the speech material was designed and validated for many languages. The objective of the present study was to evaluate the Russian version of the matrix sentence test (RuMatrix test) in the listeners of different ages with normal hearing. At the first stage of the study, 35 listeners at the age from 18 to 33 year were examined. The results of the estimation of the training effect dictated the necessity of conducting two training tracks before carrying out the RuMatrix test proper. The signal-to-noise ratio at which 50% speech recognition (SRT50) was obtained was found to be -8.8±0.8 dB SNR. A significant effect of exposure to the background noise was demonstrated: the noise level of 80 and 75 Db SPL led to a considerably lower intelligibility than the noise levels in the range from 45 to 70 dB SPL; in the subsequent studies, the noise level of 65 dB SPL was used. The high test-retest reliability of the RuMatrix test was proved. At the second stage of the study, 20 young (20-40 year old) listeners and 20 aged (62-74 year old) ones were examined. The mean SRT50 in the aged patients was found to be -6.9±1.1 dB SNR which was much worse than the mean STR50 in the young subjects (-8.7±0.9 dB SNR). It is concluded that, bearing in mind the excellent comparability of the results of the RUMat rix test across different languages, it can be used as a universal tool in international research projects.

Tissue distribution of rat macroglobulins in tumour-bearing rats.

Rat macroglobulins were determined in blood sera and extracts of tissues of intact rats and rats with Walker carcinoma by rocket immunoelectrophoresis. The serum levels of alpha1-macroglobulin (alpha1MG) alpha2-macroglobulin (alpha2MG) and pregnancy-associated alpha1-glycoprotein (alpha1PAG) were 1.86 +/- 0.07 mg/ml, 0.12 +/- 0. 02 mg/ml and 18.32 +/- 4.07 AU/ml respectively in control rats. Maximum concentrations of alpha1MG were found in heart, lung and spleen and lesser quantities were in liver and thymus, while alpha2MG and alpha1PAG were not found at all in tissue extracts from control rats. Serum alpha2MG and alpha1PAG concentrations increased more than 30-fold in tumour-bearing rats compared to control animals, while alpha1MG serum concentration was little changed. Increases in all three macroglobulins occurred in the tissues of tumour-bearing rats, particularly alpha1PAG. The tissue concentrations of alpha1MG and alpha2MG were similar and the tissue distribution was also similar with highest concentrations in heart and lung. Considerable quantities of the proteins were found in the tumour and part of peritoneum which made contact with the tumour. Changes in the protein concentrations in serum and tissue extracts of tumour-bearing rats suggest that all members of rat macroglobulin family are disturbed during the development of the Walker carcinoma, though only alpha2MG and alpha1PAG were substantially elevated.

The Comparison of Immunoregulatory Properties of Human Alpha2-Macroglobulin and Pregnancy-Associated Alpha2-Glycoprotein.

Human alpha2-macroglobulin (MG) and pregnancy-associated alpha2-glycoprotein (PAG) are able to suppress proliferation of non-fractionated mononuclear blood cells and T- and B-enriched populations in spontaneous and mitogen-stimulated cultures in vitro. Immunosuppressive properties of both proteins are more expressed in mitogen-stimulated cultures than in spontaneous ones, and in T population than in B one. PAG is a more powerful immunosuppressor, because its suppressive effect is more than ten-fold greater than corresponding effect of MG. Female peripheral blood mononuclear cells are more susceptible to immunoregulatory effect of alpha2-glycoprotein than male ones. This fact may confirm the known alpha2-glycoprotein role as an immunoregulator in pregnancy.

Immunoregulatory Properties of alpha(2)-Macroglobulin.

Native and modified with ammonium ions alpha(2)-macroglobulin forms exhibit similar abilities to influence proliferative activity and secretion of immunoglobulins in cultures of human blood mononuclear cells in vitro. Effects of modified with ammonium ions alpha(2)-macroglobulin were more significant than those of native alpha(2)-macroglobulin. Revealed properties of native alpha(2)-macroglobulin could be conditioned by a partial modification of its structure with endogenous proteinases or cytokines, some of which were shown to be common affinants for both forms.