Effect of Grinding Process Parameters and Storage Time on Extraction of Antioxidants from Ginger and Nutmeg.

The aim of this study was to optimize the grinding process parameters (mesh size of grinder sieve (X1), the peripheral velocity of the grinding wheels (X2)), and the storage time (X3) of ground ginger rhizome and nutmeg to obtain ethanol and ethanol-water extracts with improved antioxidant properties. The optimal conditions were estimated using response surface methodology (RSM) based on a three-variable Box-Behnken design (BBD) in order to maximize the antioxidant capacity (AC) determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods, and the total phenolic content (TPC) was determined by the Folin-Ciocalteu (F-C) method in spice extracts. Additionally, the phenolic acid profiles in extracts from optimized conditions were analyzed using ultra-performance liquid chromatography (UPLC). It was found that the optimal preparation conditions for antioxidant extraction were dependent on the spice source and solvent type. The best antioxidant properties in nutmeg extracts were achieved for X1 = 1.0 mm, X2 = 40-41 Hz and X3 = 7 days, whereas the optimized parameters for ginger extracts were more varied (1.0-2.0 mm, 43-50 Hz and 1-9 days, respectively). The ginger extracts contained 1.5-1.8 times more phenolic acids, and vanillic, ferulic, gallic, and p-OH-benzoic acids were dominant. In contrast, the nutmeg extracts were rich in protocatechuic, vanillic, and ferulic acids.

Impact of Bioactive Compounds of Plant Leaf Powders in White Chocolate Production: Changes in Antioxidant Properties during the Technological Processes.

Bioactive compounds present in the powdered leaves of matcha green tea (Camellia sinensis L.) (MGTP) and moringa (Moringa oleifera) (MOLP) seem to be related to health benefits due to their antioxidant properties. The growing accessibility of these powders has led to their being more widely used in food production. The aim of this study was to evaluate the total phenolic content (TPC) and antioxidant capacity (AC) of white chocolate (WCh) supplemented with MGTP and MOLP. AC was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric ion-reducing antioxidant capacity (CUPRAC), and ferric-reducing antioxidant power (FRAP) assays, whereas TPC was determined by the Folin-Ciocalteu (FC) method. Both additives were incorporated at four levels (1, 2, 3 and 4%) in two chocolate processing steps (conching and tempering). Additionally, the amounts of phenolic acids, tocopherols, and carotenoids in WCh samples enriched by MGTP and MOLP were determined to explain their influence on AC. The results showed that the chocolates supplemented with MGTP were characterized by higher antioxidant properties than those with MOLP. In turn, MOLP significantly increased the content of lipophilic antioxidants in chocolates, tocopherols and carotenoids, which also exhibit pro-health effects. Furthermore, the incorporation of these additives during the tempering process was more relevant to the improvement of the antioxidant properties of WCh.

Physicochemical, Antioxidant, Microstructural Properties and Bioaccessibility of Dark Chocolate with Plant Extracts.

In this study, dark chocolates (DCh) containing zinc lactate (ZnL) were enriched with extracts from elderberries (EFrE), elderflowers (EFlE), and chokeberries (ChFrE) to improve their functional properties. Both dried plant extracts and chocolates were analyzed for antioxidant capacity (AC) using four different analytical methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric ion-reducing antioxidant capacity (CUPRAC), and ferric-reducing antioxidant power (FRAP), while total phenolic content (TPC) was determined by Folin-Ciocalteu (F-C) assay. An increase in antioxidant properties of fortified chocolates was found, and the bioaccessibility of their antioxidants was evaluated. The highest AC and TPC were found in ChFrE and chocolate with chokeberries (DCh + ChFrE) before and after simulated in vitro digestion. Bioaccessibility studies indicated that during the simulated digestion the AC of all chocolates reduced significantly, whereas insignificant differences in TPC results were observed between chemical and physiological extracts. Moreover, the influence of plant extracts on physicochemical parameters such as moisture content (MC), fat content (FC), and viscosity of chocolates was estimated. Furthermore, scanning electron microscopy with dispersive energy spectroscopy (SEM-EDS) was used to analyze surface properties and differences in the chemical composition of chocolates without and with additives.

Studies of levels of biogenic amines in meat samples in relation to the content of additives.

The impact of meat additives on the concentration of biogenic amines and the quality of meat was studied. Fresh white and red meat samples were fortified with the following food additives: citric and lactic acids, disodium diphosphate, sodium nitrite, sodium metabisulphite, potassium sorbate, sodium chloride, ascorbic acid, α-tocopherol, propyl 3,4,5-trihydroxybenzoate (propyl gallate) and butylated hydroxyanisole. The content of spermine, spermidine, putrescine, cadaverine, histamine, tyramine, tryptamine and 2-phenylethylamine was determined by capillary isotachophoretic methods in meat samples (fresh and fortified) during four days of storage at 4°C. The results were applied to estimate the impact of the tested additives on the formation of biogenic amines in white and red meat. For all tested meats, sodium nitrite, sodium chloride and disodium diphosphate showed the best inhibition. However, cadaverine and putrescine were characterised by the biggest changes in concentration during the storage time of all the additives. Based on the presented data for the content of biogenic amines in meat samples analysed as a function of storage time and additives, we suggest that cadaverine and putrescine have a significant impact on meat quality.

'2+1' tricarbonyltechnetium(I)/tricarbonylrhenium(I) mixed-ligand complexes with methyl thiosalicylate and isocyanide ligands as potential precursors of radiopharmaceuticals.

The complexes of [(99m)Tc]-tricarbonyltechnetium(I) and [(188)Re]-tricarbonylrhenium(I), of the '2+1' type, with methyl thiosalicylate as an anionic bidentate ligand and with either tert-butyl 3-isocyanopropionate or glycine-glycine-tyrosine 4-isocyanobutyrate as monodentate ligands, have been prepared on the n.c.a. scale. The complexes exhibit different lipophilicity and high stability in neutral aqueous solutions. Based on the results of the challenge experiment with histidine, cysteine and glutathione the studied complexes might be considered to be promising models for radiopharmaceutical precursors.

[Tinnitus diagnosis and treatment on the basis of our experiences]. / Diagnostyka i leczenie szumów usznych na podstawie wlasnych doswiadczen.

INTRODUCTION: The aim of the study was to analise tinnitus diagnosis and treatment on the basis of our experiences. MATERIAL AND METHODS: 137 patients hospitalizated in Otolaryngology and Laryngological Oncology Clinic because of tinnitus (88 women - 64% and 49 men - 35,8%) were included to the study. The diagnostic procedures were unified that enabled put forward correct diagnosis. After history and otoscopy, detailed audiologic diagnostic procedures (pure tone audiometry, suprathreshold audiometry, speech audiometry, acoustic immittance measures, auditory brainstem responses) were taken. Electronystagmography and videonystagmography, tinnitus loudness match, head and neck radiologic examinations supplemented diagnostic procedures. Alternative tinnitus treatment options were applied. RESULTS: Study confirmed that tinnitus is the most frequent in patients above 50 years old (67,8% of participants). Tinnitus frequently coexist with bilateral sensorineural hearing impairment (69,1% of participants). 40,1% from asalysed group of patients complained of tinnitus of medium frequencies and 30,6% of patients complained of high frequency tinnitus. 42,3% of participants suffered from vertigo. CONCLUSIONS: The risk of tinnitus increases in patients above 55 years old that suffer from metabolic conditions and cervical spondylosis. Tinnitus frequently coexist with bilateral sensorineural hearing impairment and are bilateral or they are noticeable in better hearing ear. The most beneficial to tinnitus is causal and symptomatic treatment with several methods application.

[The value of impedance audiometry in the hearing loss diagnosis]. / Wlasne doswiadczenia w rozpoznawaniu uszkodzen sluchu za pomoca audiometrii impedancyjnej.

INTRODUCTION: The aim of this work was to assess the value of impedance audiometry in the differential diagnostics of hearing disorders, especially in patients suffering from tinnitus. MATERIAL AND METHODS: The analysis dealt with results of the audiological tests in 198 patients (116 female and 82 male), hospitalised in 2007 due to their hearing deterioration, tinnitus or sudden deafness. The conducted audiological tests covered threshold and suprathreshold pure tone audiometry, speech audiometry, BERA and impedance audiometry. RESULTS OF THE STUDIES: Women (58.5%) and people over 50 years old (58.6%) constituted the majority of the patients. In 166 (83.8%) patients the conducted tests via impedance audiometry did not prove any deviations from the normal condition, the lesions referred to both ears in 32 (16.9%) patients and one ear in 17 (8.5%) patients. An incorrect tympanogram was found in 23 people, including type As in 11, type Ad in 2, type B in 4 and type C in 6 subjects. Low values of acoustic receptivity of the middle ear were noted in 20 ears, whereas high values in 11 ears. In 3 ears we found low values of the gradient (below 0.3), high values--in 11 ears. The middle ear pressure between -170 and -350 daPa was noticed in 20 ears, and positive values, above +50 daPa up to +75 daPa, in 3 ears. Disorders in the stapedial reflex registration were observed in 38 (19.1%) patients. The assessment of the conducted subjective and objective audiological examinations allowed to recognise bilateral perceptive hearing injuries in 139 patients, including 49 (25.9%) of cochlear origin with OWG, in further 70 patients the hearing loss referred to higher frequencies and was rather slight. CONCLUSIONS: The own experiences indicated that the impedance audiometry constitutes the integral part of contemporary audiological diagnostics and still remains an objective method facilitating quick, non-invasive evaluation of the functions of particular elements in the middle ear.

HPLC columns partition by chemometric methods based on peptides retention.

In recent years, multivariate techniques have been utilized to evaluate reversed-phase high-performance liquid chromatographic data. In the present study, 11 high-performance liquid chromatography (HPLC) columns were divided into several groups according to the retention factors of 12 peptides. Principal component analysis (PCA) and cluster analysis (CA) were used in column and peptides' comparison and grouping. CA results indicated that all stationary phases may be generally grouped into several clusters, due to stationary phase structure and properties. On the other hand, interesting results were obtained with the use of PC. There is almost linear relationship between classified HPLC columns in the space of new PCs, which is connected with meaning of the PC's reflected in their loading values. The first component describes non-polar properties of peptides, whereas the second component is loaded with polar peptides having much lower logP values. PCA and CA were also used in peptides comparison however, complete explanation of peptides grouping still remains unclear.

Mobile-phase pH influence on the retention of some benzoic acid derivatives in reversed-phase chromatography.

Five end-capped octadecyl RP stationary phases, among which one was a polar embedded stationary phase, were tested for the analysis of benzoic acid derivatives using two mobile phases with or without addition of formic acid (water pH was measured by a common approach; pH of water with addition of formic acid was 3.0 and without formic acid 5.8). The influence of mobile-phase pH on the retention of benzoic acid derivatives was under study. Consequently, Purospher-STAR and Alltima columns provided symmetrical peaks for benzoic acid derivatives at pH 3.0 and also at pH 5.8. Reprosil and Symmetry stationary phases showed poor peak shapes at higher pH of the mobile phase. Differences between the tested columns may be caused by surface heterogeneity. Another reason may be the presence of some atoms creating additional adsorption sites on the surface of Reprosil and Symmetry stationary phases. This can lead to enhanced silanol activity resulting in peak tailing. The addition of formic acid into the mobile phase improved peak shapes. The polar embedded C18 stationary-phase Synergi-Fusion-RP appeared as not a suitable column for the analysis of benzoic acid derivatives. Synergi-Fusion-RP provided asymmetrical peaks even if formic acid was added into the mobile phase.

Influence of stationary phase properties on the separation of ionic liquid cations by RP-HPLC.

Different types of columns with specific structural properties were used for the separation of mixtures of ionic liquid cations. Two of them were home-made packings and the other two were commercial stationary phases. One of the home-made packings contained cholesterol ligands bonded chemically to silica (SG-CHOL) whereas the other one was a mixed stationary phase (SG-MIX) with cyanopropyl, aminopropyl, phenyl, octyl, and octadecyl ligands. RP-18e Innovation ChromolithTM Performance and Macrosphere 300 C4 packings were also used. A comparison of the separation possibilities offered by these columns for the substances in question revealed significant differences in performance. Packings containing surface-bonded functional groups that are able to undergo protonation are not suitable for separation of such compounds under the given analysis conditions (pH = 4). The best results were obtained for two alkyl stationary phases: butyl and octadecyl. Cluster analysis has also been performed for comparison of the ionic liquid cation properties.

Some remarks on characterization and application of stationary phases for RP-HPLC determination of biologically important compounds.

Biologically active compounds such as vitamins, steroids, nucleosides, peptides and proteins play a very important role in coordinating living organism functions. Determination of those substances is indispensable in pathogenesis. Their complex structure and physico-chemical properties cause many analytical problems. Chromatography is the most common technique used in pharmaceutical and biomedical analysis. The interaction between analyte and stationary phase plays a major role in the separation process. The structure of the packing has a significant influence on the results of the separation process. Various types of spectroscopic techniques, such as nuclear magnetic resonance spectroscopy, infrared spectroscopy, fluorescence spectroscopy and photoacoustic spectroscopy can be useful tools for the characterization of packings. Surface area measurements, elemental analysis, thermal analysis and microcalorimetric measurements are also helpful in this field. Part of the paper contains a description of chromatographic tests used for the determination of column properties. The description of the possibilities of surface characterization is not complete, but is focused on the most popular techniques and practical chromatographic tests. All the presented methods made possible the design and quality control of a new generation stationary phases, which are the future of high-performance liquid chromatography.

Effect of stationary phase polarity on the retention of ionic liquid cations in reversed phase liquid chromatography.

Chromatographic analysis of ionic liquids on different types of packings offers interesting possibility to determine their retention mechanism. As a consequence, the major interactions between stationary phase ligands and analyzed chemical entities can be defined. The main aim of this work was to analyze cations of ionic liquids on chemically bonded stationary phases with specific structural properties. The attempt to predict the main interactions between positive ions of ionic liquids and stationary phase ligands was undertaken. For that purpose, butyl, octyl, octadecyl, phenyl, aryl, mixed, alkylamide, and cholesterolic packings were chosen and applied to the analysis of six most commonly used ionic liquids' cations. Obtained results indicate mainly dispersive and pi-pi type of interaction part in the retention mechanism of analyzed compounds.

The influence of the mobile phase pH and the stationary phase type on the selectivity tuning in high performance liquid chromatography nucleosides separation.

Analysis of the modified nucleosides is particularly important in the medical area because of a possibility of cancerogenic processes studies. The aim of this work was to study the selectivity tuning of modified nucleosides through the investigations of interactions analyte (modified nucleoside) <==> stationary phase <==> mobile phase. A series of homemade stationary phases with different surface properties has been utilized. All of them contain various interaction sites such as: cholesterol (SG-CHOL); n-acylamide (SG-CHOL, SG-AP); aminopropyl (SG-CHOL, SG-AP, SG-NH2, SG-MIX); cyanopropyl, phenyl, octyl (SG-MIX), octadecyl (SG-MIX, SG-C18) and silanols localized on the silica gel surface of all packings. The attempt to predict the main interactions responsible for the retention between nucleosides and stationary phase ligands was done on the basis of the elemental analysis, and proportional part of an individual ligand bonded to silica surface results. In order to study the influence of different packing types on the analyzed nucleosides retention, the relationship between pH of the mobile phase buffer and the selectivity of a stationary phase was investigated.

Occupational voice disorders: an analysis of diagnoses made and certificates issued in 1999-2004.

OBJECTIVES: It has been decided to identify the most frequent diseases of the larynx in people occupationally exposed to a considerable voice load and to assess the feasibility of using videostroboscopy to diagnose voice disorders and their organic effects in order to improve the reliability of certification of occupational vocal organ diseases as well as to evaluate the functioning of new regulations on diagnosing and certifying occupational vocal organ diseases and to assay the conformity of clinical diagnoses made at voivodeship (provincial) centers (level I) with those made at scientific research institutes (level II). MATERIALS AND METHODS: The study involved an analysis of 1261 cases (1042 women and 219 men) with the vocal organ disorders referred to the ENT Unit, Nofer Institute of Occupational Medicine, Lódz, by voivodeship centers during 1999-2004 for consultation or under the appeal procedure (if applicants were denied the right to be included in the category of patients with occupational disease of the vocal organ). The majority of the patients (65.7%) were primary school teachers, and those aged 51-60 years made 54.8%. Laryngological, phoniatric and videostroboscopic examinations, when necessary, supplemented with other testing procedures (paranasal sinus imaging, allergenic tests) were taken to assess the clinical state of the patients. RESULTS: As a result of these comprehensive examinations, organic changes in the larynx were detected in 161 (12.7%) cases, including 139 (11.0%) women and 22 (1.7%) men. According to current diagnostic/certifying criteria those pathologies could be classified into the category of occupational disease of the vocal organ. Paresis of vocal folds due to the insufficiency of vocal fold adductor and tensor muscles with permanent dysphonia was found in 97 (7.6%) patients, vocal nodules in 53 (4.2%) and secondary hypertrophy changes in vocal folds in 11 (0.87%) patients. The most frequent reasons for excluding the occupational etiology of the disease were functional disorders of the voice observed in 82.3% of patients in the form of hyperfunctional dysphonia (64.3%), hypofunctional dysphonia (17.0%) and dysfunctional dysphonia (about 1.0%). In 9.0% of patients, the functional disorders of the voice were accompanied by organic changes in the larynx caused by non-occupational factors. CONCLUSIONS: The analysis showed that due to new Polish regulations, the number of certified occupational disease of the vocal organ was reduced; videostroboscopic tests proved to be a very helpful tool for discriminating between the functional and organic disorders of the vocal organ; and good agreement between clinical diagnoses issued at both levels (I and II) was also revealed.

Phenol and catechol induce prehemolytic and hemolytic changes in human erythrocytes.

The toxic potency of two industrially used compounds (phenol and catechol) was studied in human blood cells in vitro. Catechol was found to be a more harmful toxin than phenol, since it provokes statistically significant changes in the function of erythrocytes even at low doses. Most of the changes was statistically significant for the doses of 50 ppm of catechol and 250 ppm of phenol. Both compounds induced methaemoglobin formation, glutathione depletion and conversion of oxyhaemoglobin to methaemoglobin, which is associated with superoxide anion production and lead to formation of ferryl hemoglobin, hydrogen peroxide or hydroxyl radicals. It is known that oxidation of catechol leads to formation of semiquinone radicals. Semiquinones are able to bind to nucleophilic residues like -SH or -NH2 of proteins and these macromolecules may undergo inactivation. We observed among especially susceptible to action of catechol are catalase (CAT) (100 ppm) and superoxide dismutase (SOD) (250 ppm). Decrease of the activity of catalase and SOD by catechol induced radical species formation. This lead to inhibition of another protective enzymes such as glutathione-S-transferase (500 ppm), glutathione reductase (1000 ppm), glucose-6-phosphate dehydrogenase activity (1000 ppm). Cytotoxicity of phenol or catechol was noted as hemolysis. Haemoglobin liberated from erythrocytes in this process may further generate oxygen free radicals and subsequently initiate enzymes damage. It seems to be essential that in phenol and catechol toxicity special role play damages of heme proteins and other proteins molecule, and damages of lipids are not so important.

Epidemiology of occupational noise-induced hearing loss (ONIHL) in Poland.

Noise-induced hearing loss is a major health risk worldwide. In Europe about 35 million people are exposed to detrimental noise levels (> 85 dB-A) in industrial plants, and occupational deafness is a leading occupational compensible disease in the all countries; it is an insidious slow process that develops over a period of approximately 10 to 20 years. Accordingly to the latest estimations, more than 650,000 workers (of a total 5 million employed in industry) are put at risk in Poland. Despite progress in engineering approaches for reducing noise in the work environment and in improving hearing conservation programs (both the technical and medical) the ONIHL still remains a common and costly disability. The aim of this study is presentation of the most recent data on the incidence of ONIHL in Poland in the years 1992-2002 considered to be a base for implementing the effective prophylactic activities. The analysed data were derived from the central state register which collects all cases of occupational diseases recognized in the country. The highest incidence was found in such key industrial branches as coal mining, iron and steel, metallurgical and transport equipment; majority of cases were observed in southern and western provinces, mainly in the Silesian district, known from the significant concentration of noisy enterprises. The most affected were those workers aged 50-59 years and exposed to noise for over 20 years. More than 30 new cases of ONIHL were identified in the years 1992-1998 annually per 100,000 employees, and with beginning 1999 the rate was significantly decreased to 10 cases in 2002. One may presume that it results from the set up of national program of hearing preservation introduced in 1999 with obligatory pre-employment and follow-up pure-tone audiometry, as well as with hearing screening by means of the otoacoustic emissions.

Nasal lavage fluid examination and rhinomanometry in the diagnostics of occupational airway allergy to laboratory animals.

OBJECTIVES: The purpose of this studywas to compare the cellular and biochemical findings in the nasal lavage fluid (NALF) and nasal resistance changes due to a challenge with laboratory animal allergens in 25 patients with occupational asthma and rhinitis, in 22 patients with atopic asthma and rhinitis sensitized to house dust mite, and in 15 healthy subjects. METHODS: Skin prick tests with common and occupational allergens, total serum IgE level, specific anti-allergens IgE, spirometry and nasal lavages were performed. RESULTS: In patients with occupational airway allergy, nasal symptoms of varying severity developed directly after specific nasal challenge. The total symptom score immediately and 24 h after specific challenge was significantly correlated with expiratory nasal resistance (ENR). The percentage of eosinophils and basophils in NALF increased significantly 5 and 24 h after specific challenge in patients with occupational asthma and it was correlated with ENR. The authors did not observe any significant increase in the percentage of eosinophils, basophils and in the level of albumin in NALF of patients with non-occupational allergy and healthy subjects at any time-point after specific challenge. None of the healthy subjects and patients with non-occupational allergy developed either allergic symptoms or increased ENR after the challenge with laboratory animal allergens and placebo. CONCLUSIONS: The prolonged increase in the percentage of eosinophils, basophils and in the level of albumin seems to reflect allergic inflammation. The intensity of inflammation during the specific reaction is related to the symptom score and to ENR in occupational allergics.

Effects of occupational exposure to a mixture of solvents on the inner ear: a field study.

Some clinical and laboratory studies indicate that industrial solvents such as toluene, styrene, xylene, trichloroethylene and carbon disulfide or their mixtures may affect the inner ear, although the mechanism of this process is still not well understood. The aim of this investigation was to assess the incidence of hearing and vestibular disorders (using modem audiological and vestibular tests) in 61 workers exposed to a mixture of organic solvents at the production of paints and varnishes; the control group included 40 age-matched non-exposed subjects. Environmental and biological monitoring revealed that the most significant exposure can be attributed to the following mixture constituents: ethylbenzene, xylene and trimethylbenzene isomers such as pseudocumene, mesitylene and hemimellitene. Electronystagmographic examinations showed the symptoms of vestibular dysfunction, as well as the decreased duration, amplitude and slow phase angular velocity of induced nystagmus in 47.5% of the subjects exposed versus 5% of controls. This was accompanied by sensorineural high frequency hearing loss, identified by means of pure tone audiometry in 42% of those exposed versus 5% controls, and reduced amplitudes of transiently evoked and distortion-product otoacoustic emissions. The findings closely correspond with the rate of the total exposure to the solvent mixture. A possible mechanism responsible for ototoxicity of solvents is discussed.

[Occupational hearing loss: new diagnostic opportunities]. / Zawodowe uszkodzenie sluchu: nowe mozliwosci diagnostyczne.

Noise-induced hearing loss together with presbyacusis are the most frequent causes of the disorders of the inner ear among adults. The authors present briefly epidemiological, diagnostic and certification aspects of this issue. Their attention was mainly focused on the role of objective methods of hearing examinations (impedance audiometry, brainstem electric response audiometry, recording of otoacoustic emissions) in diagnostic procedures. A growing significance of these methods, especially in frequent cases of the aggravation and simulation among persons who claim for certification of occupational noise-induced hearing loss, was highlighted.

[Tinnitus Center at the Nofer Institute of Occupational Medicine--earliest experience]. / Osrodek Diagnostyki i Leczenia Szumów Usznych Instytutu Medycyny Pracy w Lodzi--pierwsze doswiadczenia.

Of the 150 patients admitted in 2001 to the Tinnitus Center located at the Nofer Institute of Occupational Medicine, Lódz, Poland, 80 were subjected to complex examinations consisted of standardized questionnaire on medical history, psychological tests and audiological assessment. The diagnostic procedure was completed for 52 patients (23 females and 29 males; mean age: 53 years). In this group, five patients were found to have conductive hearing loss due to chronic eustachtis or otosclerosis. They were excluded from further studies. Among the other 47 patients, 26 showed normal hearing threshold and 21 suffered from uni- or bilateral sensorineural hearing loss. Hyperacusis was diagnosed in 16 cases. The measurements of brainstem evoked potentials revealed V wave latency asymmetry in 7 cases, which implied the necessity to perform CT or MNR. In neither of cases did this diagnosis confirm the suspected tumor development (n. VIII neurinoma or pontocerebral angle tumor. The preliminary assessment of treatment efficacy for subjective tinnitus with use of retraining therapy yielded the following conclusions: 1. The application of hearing aid brings about an immediate improvement in the patient's self-assessment of hearing and a better tolerance towards tinnitus. 2. A systematic all-day wear of noise generators contributes to the patient's increased tolerance towards tinnitus, improved mental condition and alleviated hyperacusis. 3. The efficacy of the tinnitus retraining therapy, following Jastreboff, depends on providing the patient with detailed information on the causes and mechanisms of tinnitus development. 4. The negative diagnostics for tumor within the cranial cavity has not only a soothing effect on the patient as it relieves his/her stress, but it can also be a good starting point for the tinnitus retraining therapy.