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442. The effect of fetal calf serum on human dental pulp stem cells
- Creator:
- Suchánek, Jakub, Suchánková Kleplová, Tereza, Kapitán, Martin, and Soukup, Tomáš
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, srovnávací studie, časopisecké články, práce podpořená grantem, and TEXT
- Subject:
- zvířata, skot, proliferace buněk, buňky kultivované, zubní dřeň--cytologie, ženské pohlaví, fetální krev--cytologie, lidé, mužské pohlaví, kmenové buňky--cytologie, and mladý dospělý
- Language:
- English
- Description:
- AIMS: Authors studied potential side effects of fetal calf serum (FCS) in cultivation media on human dental pulp stem cells (DPSC) during long-term cultivation. METHODS: Two lines of DPSC obtained healthy donors (male 22 years, female 23 years) were used. Both lines were cultivated under standard cultivation conditions in four different media containing 10% or 2% FCS and substituted with growth factors. During long-term cultivation proliferation ability, karyotype and phenotype of DPSC were measured. RESULTS: Both lines of DPSC cultivated in a media containing 2% FCS and ITS supplement showed the highest number of population doublings. On the other hand the proliferation rate of DPSC cultivated in a media with 2% FCS without ITS supplement was slowest. Proliferation rate of DPSC cultivated in 10% FCS media with or without FGF-2 was comparable. DPSC cultivated in a media with 10% FCS showed a significantly higher amount of chromosomal aberrations. These chromosomal aberrations do not seem to be clonal but surprisingly we found large amounts of tetraploid cells in the 9th passage in both media containing 10% FCS. CONCLUSIONS: Our study proved that cultivation of DPSC in media containing higher concentration of FCS has critical side effects on cell chromosomal stability. and J. Suchánek, TS. Kleplová, M. Kapitán, T. Soukup
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
443. The effect of L-carnosine on erythrocyte deformability and aggregation according to the cell age in young and aged rats
- Creator:
- Erken, Gülten, Bor-Kucukatay, Melek, KilicToprak, Emine, Akdag, Beyza, and Kucukatay, Vural
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, časopisecké články, and TEXT
- Subject:
- věkové faktory, zvířata, karnosin--farmakologie, stárnutí buněk--fyziologie, erytrocyty - agregace--účinky léků, erytrocyty - měnlivost tvaru--účinky léků, mužské pohlaví, oxidační stres--fyziologie, krysy, and potkani Sprague-Dawley
- Language:
- English
- Description:
- This study aimed to investigate alterations in hemorheology induced by L-carnosine, an anti- oxidant dipeptide, and to determine their relationship to oxidative stress in density-separated erythrocytes of aged and young rats. 28 male Sprague Dawley rats were divided into 4 groups as aged (Aca), young (Yca) L-carnosine groups (250 mg/kg L-carnosine, i.p.) and aged (As), young (Ys) control groups (saline, i.p.). Density separation was further performed to these groups in order to separate erythrocytes according to their age. Blood samples were used for the determination of erythrocyte deformability, aggregation; and oxidative stress parameters. Erythrocyte deformability of Yca group measured at 0.53 Pa was lower than Aca group. Similarly, deformability of least-dense (young) erythrocytes of Yca group was decreased compared to least-dense erythrocytes of Aca groups. Total antioxidant capacity (TAC) of Aca group was higher and oxidative stress index (OSI) lower than As group. Although L-carnosine resulted in an enhancement in TAC of aged rats, this favorable effect was not observed in erythrocyte deformability and aggregation in the dose applied in this study. and G. Erken, M. Bor-Kucukatay, E. KilicToprak, B. Akdag, V. Kucukatay
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
444. The effect of wheat allergy on the course of atopic eczema in patients over 14 years of age
- Creator:
- Čelakovská, Jarmila, Ettlerová, Květuše, Ettler, Karel, Vaněčková, Jaroslava, and Bukač, Josef
- Format:
- braille, text, and regular print
- Type:
- model:article, article, Text, and TEXT
- Subject:
- mladiství, dospělí, atopická dermatitida--etiologie--patologie, ženské pohlaví, lidé, imunoglobulin E--krev, mužské pohlaví, Patch Tests, Skin Tests, Wheat Hypersensitivity--co [Complications], and Wheat Hypersensitivity--di [Diagnosis]
- Language:
- English
- Description:
- Few studies concerning the importance of wheat allergy affecting the course of atopic eczema in adolescents and adult patients exist. Aim: The evaluation if wheat allergy can deteriorate the course of atopic eczema. Follow-up of patients with confirmed food allergy to wheat. Method: Altogether 179 persons suffering from atopic eczema were included in the study: 51 men and 128 women entered the study with an average age of 26.2 (s.d. 9.5 years) Dermatological and allergological examinations were performed, including skin prick tests, atopy patch tests, and specific serum IgE for wheat, open exposure test and double-blind, placebo-controlled food challenge test with wheat flour. Results: Wheat allergy affecting the coures of atopic eczema was confirmed in eight patients (4.5%) out of 179 patients enrolled in this study by double-blind, placebo controlled food challenge test. The course of atopic eczema showed a positive trend in patients with confirmed food allergy at 3, 6, 9, 12 month follow-up (statistical evaluation with paired t-test) after the elimination of wheat flour. Conclusion: Wheat allergy may play an important role in the worsening of atopic eczema (acting as a triggering exacerbating factor) only in a minority of adolescents and adult patients (4.5% in our study). The diagnostic methods (skin prick test, specific IgE, atopy patch test, history) cannot be used as separated tests for the determination of food allergy to wheat in patients with atopic eczema.Open exposure tests and double-blind, placebo-controlled food challenge should be used for the confirmation of wheat allergy affecting the course of atopic eczema., Jarmila Čelakovská, Květuše Ettlerová, Karel Ettler, Jaroslava Vaněčková, Josef Bukač, and Literatura 34
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
445. The evaluation of the potency of newly developed oximes (K727, K733) and Trimedoxime to counteract acute neurotoxic effects of tabun in rats
- Creator:
- Kassa, Jiří, Hatlapatková, Jana, and Žďárová, Jana
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, časopisecké články, práce podpořená grantem, and TEXT
- Subject:
- zvířata, atropin--farmakologie, inhibitory cholinesteráz--toxicita, cholinesterasové reaktivátory--farmakologie, mužské pohlaví, antagonisté muskarinových receptorů--farmakologie, nervový systém--účinky léků, neuroprotektivní látky--farmakologie, neurotoxické syndromy--farmakoterapie--etiologie, otrava organofosfáty--farmakoterapie--etiologie, organofosfáty--toxicita, oximy--farmakologie, pyridinové sloučeniny--farmakologie, krysy, potkani Wistar, and trimedoxim--farmakologie
- Language:
- English
- Description:
- AIM: The ability of two newly developed oximes (K727, K733) to reduce tabun-induced acute neurotoxic signs and symptoms was evaluated and compared with currently available trimedoxime in rats. METHODS: The neuroprotective effects of the oximes studied combined with atropine on Wistar rats poisoned with tabun at a lethal dose (380 µg/kg i.m.; 90% of LD50 value) were evaluated. Tabun-induced neurotoxicity was monitored by the functional observational battery consisting of 38 measurements of sensory, motor and autonomic nervous functions at 2 hours following tabun challenge. RESULTS: All tested oximes combined with atropine enable tabun-poisoned rats to survive till the end of experiment. Both newly developed oximes (K727, K733) combined with atropine were able to decrease tabun-induced neurotoxicity in the case of lethal poisoning although they did not eliminate all tabun-induced acute neurotoxic signs and symptoms. CONCLUSION: The ability of both novel bispyridinium oximes to decrease tabun-induced acute neurotoxicity was slightly lower than that of trimedoxime. Therefore, the newly developed oximes are not suitable for the replacement of commonly used oximes such as trimedoxime in the treatment of acute tabun poisonings. and J. Kassa, J. Hatlapatková, J. Žďárová Karasová
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
446. The number of immunoregulatory T cells (Treg) is increased in patients with psoriasis after Goeckerman therapy
- Creator:
- Kondělková, Kateřina, Vokurková, Doris, Krejsek, Jan, Borská, Lenka, Fiala, Zdeněk, Hamáková, Květoslava, and Andrýs, Ctirad
- Format:
- braille, text, and regular print
- Type:
- model:article, article, Text, práce podpořená grantem, and TEXT
- Subject:
- dospělí, dehet uhelný--terapeutické užití, dermatologické látky--terapeutické užití, ženské pohlaví, lidé, počet lymfocytů, mužské pohlaví, lidé středního věku, psoriáza--imunologie--terapie, T-lymfocyty regulační--imunologie, and terapie ultrafialovými paprsky
- Language:
- English
- Description:
- Regulatory T cells (Treg) are a specialized subpopulation of T cells that act to suppress inadequate immune response. Psoriasis is recognized as a T -cell driven immune-mediated systemic inflammatory disease with skin manifestation. Effective therapeutical approach to treat psoriasis is Goeckerman therapy (GT ). The aim of this study was to compare the number of Treg in the peripheral blood of 27 psoriatic patients and 19 controls and to evaluate the influence of GT on Treg population in peripheral blood of patients with psoriasis. There was no significant difference in the relative number of Treg cells in the peripheral blood of healthy blood donors and patients with psoriasis before initiation of GT (P = 0.2668). In contrary, the relative number of Treg cells in peripheral blood of patients with psoriasis after GT was significantly higher than those found in healthy blood donors (P = 0.0019). Moreover, the relative number of Treg is significantly increased in psoriatic patients after Goeckerman therapy compared to the pre-treatment level (P = 0.0042). In conclusion, this significant increase in Treg count after GT is probably associated with amelioration of inflammation by GT , as disease activity expressed as PASI decreased in our patients by GT (P = 0.0001)., Kateřina Kondělková, Doris Vokurková, Jan Krejsek, Lenka Borská, Zdeněk Fiala, Květa Hamáková, Ctirad Andrýs, and Literatura 39
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
447. The prevalence of decreased glomerular filtration rate in patients with monoclonal gammopathy of undetermined significance
- Creator:
- Šálek, Tomáš, Moravčíková, D., Humpolíček, Petr, Tichý, Miloš, and Palička, Vladimír
- Format:
- braille, text, and regular print
- Type:
- model:article, article, Text, and TEXT
- Subject:
- retrospektivní studie, prevalence, chronická renální insuficience--diagnóza--epidemiologie, monoklonální gamapatie nejistého významu--patofyziologie--patologie, glomerulární filtrace - hodnota, imunoglobuliny - lehké řetězce--diagnostické užití, statistika jako téma, cystatin C--diagnostické užití, kreatinin--diagnostické užití--krev, diabetes mellitus, ženské pohlaví, lidé, and mužské pohlaví
- Language:
- Czech and English
- Description:
- Cíl: Cílem studie je stanovit prevalenci chronického selhání ledvin u 101 pacientů s monoklonální gamapatií neurčeného významu (MGUS). Typ studie: retrospektivní studie. Materiál a metody: Porovnali jsme glomerulární filtraci odhadovanou ze sérového kreatininu a cystatinu C a hodnotili jsme korelaci mezi koncentrací volných lehkých řetězců v séru a funkcí ledvin. U všech pacientů jsme provedli elektroforézu pro - teinů séra s denzitometrickou kvantifikací monoklonálního imunoglobulinu a změřili jsme koncentraci kreatininu, cystatinu C, volných lehkých řetězců kappa a lambda, β 2 mikroglobulinu. Výsledky: Chronické selhání ledvin jsme nalezli u 38,6 % pacientů na základě odhadu ze sérového cystatinu C a u 34,6 % pacientů na základě odhadu ze sérového kreatininu. B2mikroglobulin má největší počet významných korelací; cystatin C (0,90), CysC GFR (-0,69), Kreatinin (0,70), MDRD GFR (-0,60), MIg koncentrace (0,24), κ FLC (0,22) λ FLC (0,34) a věk (0,40). Tento velký počet korelací lze vysvětlit tím, že β 2mikroglobulin odráží jak zátěž organismu maligními buňkami, tak pokles glomerulární filtrace. Závěr: Chronické selhání ledvin jsme nalezli u 38,6 % pacientů při odhadu glomerulární filtrace z cystatinu C a u 34,6 % při odhadu ze sérového kreatininu. Třída monoklonálního imunoglobulinu může mít vliv na výsledky odhadu glomerulární filtrace ze sérového cystatinu C, odhad glomerulární filtrace ze sérového kreatininu není ovlivněn třídou imunoglobulinu. Diabetici neměli statisticky signifikantně nižší glomerulární filtraci než pacienti bez diabetu mellitu., Background: Renal function is more frequently decreased in patients with monoclonal gammopathy. 10 % of patients with multiple myeloma present with acute renal failure and renal function is included in CRAB criteria for the diagnosis of multiple myeloma. Aim: The aim of this study is to determine the prevalence of chronic renal failure (CRF), defined as a glomerular filtration rate (GFR) below 1.0 ml/s/1.73m 2 , in 101 patients with monoclonal gammopathy of undetermined significance (MGUS). Design: retrospective study Material and methods: We compared GFR estimates from serum creatinine (MDRD GFR) and serum cystatin C (CysC GFR) and looked at the correlation between free light chains (FLC) concentration and renal markers. We performed serum protein electrophoresis (SPE) with quantification of monoclonal intact immunoglobulin (MIg) and measured serum creatinine, cysta - tin C, κ and λ FLC and β 2microglobulin in all patients. Results: We found CRF in 38.6% patients using estimation from serum cystatin C and 34.6 % using estimation from serum creatinine. B2microglobulin has the highest number of significant correlations; cystatin C (0.90), CysC GFR (-0.69), crea - tinine (0.70), MDRD GFR (-0.60), MIg concentration (0.24), κ FLC (0.22) λ FLC (0.34) and age (0.40). The best correlation results may be explained by the fact that β 2microglobulin reflects both malignant cells burden and renal function. Conclusions: We found CRF in 38.6 % MGUS patients using estimation from serum cystatin C and in 34.6 % using estima - tion from serum creatinine. The class of monoclonal immunoglobulin may influence results of glomerular filtration estimated from cystatin C but it does not influence GFR estimated from creatinine. Diabetic patients had not significantly lower GFR than patients without diabetes mellitus., Šálek T., Moravčíková D., Humpolíček P., Tichý M., Palička V., and Literatura
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
448. The prevalence of musculoskeletal disorders among dentists in the Czech Republic
- Creator:
- Šustová, Zdeňka, Hodačová, Lenka, and Kapitán, Martin
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, časopisecké články, práce podpořená grantem, and TEXT
- Subject:
- dospělí, staří, staří nad 80 let, zubní lékaři, ženské pohlaví, lidé, mužské pohlaví, lidé středního věku, muskuloskeletální nemoci--epidemiologie, nemoci z povolání--epidemiologie, prevalence, průzkumy a dotazníky, mladý dospělý, and epidemiologie
- Language:
- English
- Description:
- The aim of this study was to determine the prevalence of musculoskeletal problems among Czech dentists and to analyze the factors that affect these disorders. Information was gathered through questionnaire completed by 581 physicians. The questionnaire ascertained general information about physicians including their work habits and the characteristics of their work environment along with the occurrence of musculoskeletal problems as well as their intensity. In the past year the occurrence of at least mild difficulties associated with the locomotive system was reported by 96.9% of dentists surveyed (n = 557), with 66.3% of respondents (n = 381) reporting difficulties ofa moderate or major nature. Most respondents of both sexes indicated neck pain. A statistically significant correlation with the occurrence of musculoskeletal complaints of medium and major intensity was demonstrated for the following factors: sex, age, running a private practice, past injury or musculoskeletal diseases, and the perception of work as psychologically demanding. Musculoskeletal disorders in dentists in Czech Republic are relatively frequent and serious health problem. The causes of these diseases must be identified and appropriate preventive interventions undertaken that will contribute to a reduction in the incidence of these problems. and Z. Sustová, L. Hodacová, M. Kapitán
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
449. The relationship between concentration of triacylglycerols and free radicals caused by fatty acid composition of triacylglycerols in diabetic patients
- Creator:
- Vecka, Marek, Tvrzická, Eva, and Votruba, Miloš
- Format:
- braille, text, and regular print
- Type:
- model:article, article, Text, práce podpořená grantem, and TEXT
- Subject:
- diabetes mellitus 2. typu, volné radikály--chemie, kyseliny mastné--analýza, peroxidace lipidů, triglyceridy, plynová chromatografie s hmotnostně spektrometrickou detekcí, lidé, lidé středního věku, mužské pohlaví, and ženské pohlaví
- Language:
- Czech and English
- Description:
- Cíl práce: Lipoperoxidace je dávána do příčinné souvislosti s rozvojem nejdůležitějších rizikových faktorů kardiovaskulárních onemocnění. Lipoperoxidační procesy jsou důsledkem reakcí lipidů s volnými radikály bez ohledu na jejich původ. Vztah mezi triacylglyceroly (TAG) a volnými radikály (VR) není zcela jasný. Může se dokonce stát, že hypertriacylglycerolémie je doprovázena nízkými koncentracemi VR a naopak. Jedno z možných vysvětlení spočívá ve vztahu lipoperoxidace a složení mastných kyselin v molekulách TAG. Cílem této studie bylo analyzovat vztah složení mastných kyselin v TAG a produkci VR u pacientů trpících diabetes mellitus 2. typu. Typ studie: observační s kontrolní skupinou Materiál a metody: Studie zahrnovala 18 normotriacylglycerolemických (NTG) jedinců (M/F 12/6) a 24 hypertriacylglycerolemických (HTG) jedinců (M/F 16/8). Pacienti v obou skupinách byli diabetici 2. typu. Analýzu mastných kyselin v triacylglycerolech plazmy jsme provedli kapilární plynovou chromatografií a koncentrace volných radikálů byly změřeny přímou spektrofotometrií. Statistické analýzy (parametrické i neparametrické) byly provedeny pomocí statistického software STATISTICA pro Windows. Výsledky: Ve skupině HTG jsme pozorovali nižší zastoupení kyseliny myristové (14:0) (1.62 [1.23-2.07] vs. 1.90 [1.72-2.79], p = 0.022, [medián (1.-3. kvartil]) a vyšší poměr alfa-linolenové kyseliny (18:3n-3) (1.51 [1.21-1.86] vs 1.16 [1.02-1.42], p = 0.021). Poměr kyselin arachidonové/eikosapentaenové byl ve skupině HTG nižší (5.54 [3.62-7.98] vs 7.25 [5.98-15.12], p = 0.027). Když jsme HTG skupinu dále rozdělili podle koncentrací VR na tercily, prokázali jsme nižší hodnoty poměru kyseliny arachidonová/eikosapentaenová ve druhém tercilu (4.05 [2.66-4.67] vs 7.64 [5.83-11.00], 1. tercil, a 6.21 [3.20-8.31], 3. tercil p = 0.019). V spojených HTG+NTG skupinách jsme zaznamenali negativní korelaci mezi MA a TAG (r = -0.3153, p = 0.045). V triaclylglycerolech jsme prokázali pozitivní korelace VR a kyseliny stearové (p < 0.001) spolu s negativní korelací některých n-6 vícenenasycených mastných kyselin (18:3n-6, p < 0.05, 22:5n-6, p < 0.01). Závěr: Zastoupení mastných kyselin v molekulách TAG je spojeno s tvorbou VR. Nicméně do tohoto vztahu vstupují i jiné faktory., Objective: The lipoperoxidation plays a causal role in the development of most important risk factors of cardiovascular disease. The lipoperoxidation results from the reaction of lipid molecules with free radicals, regardless of their origin. The relationship between triacylglycerols (TAG) and the free radicals (FR) amount is not clear. Thus, it can turn up that the hypertriacylglyceridaemia is accompanied with the low values of FR, or vice versa. One possible explanation of this phenomenon is that the degree of lipoperoxidation of TAG is dependent on the composition of fatty acids (FA) in their molecule. Therefore, the aim of this study was to analyze FA composition in TAG and its relationship to FR production in type 2 diabetes mellitus. Design: observational study with internal control group Material and Methods: 18 normotriacylglycerolemic (NTG) individuals (12M/6F) and 24 hypertriacylglycerolemic (HTG) patients (16M/8F). Patients in both groups were persons, suffering from type 2 diabetes mellitus. Fatty acid analysis of plasma triacylglycerols was performed by gas chromatography and free radicals were determined by direct spectrophotometric method. Statistical analyses (both parametric and non-parametric) were performed with the statistical software STATISTICA for Windows. Results: We found lower content of myristic acid (14:0) (1.62 [1.23-2.07] vs. 1.90 [1.72-2.79], p = 0.022, [median (1st-3rd quartile)]) and higher content of alpha-linolenic acid (18:3n-3) (1.51 [1.21-1.86] vs. 1.16 [1.02-1.42], p = 0.021) in HTG group. The ratio of arachidonic/eicosapentaenoic acid was in HTG group lower (5.54 [3.62-7.98] vs. 7.25 [5.98-15.12], p = 0.027). When the HTG group was stratified into the tertiles by the FR concentrations, we observed lower values in the second tertile for ratios based on arachidonic acid (20:4n-6) and eicosapentaenoic acid (20:5n-3) (4.05 [2.66-4.67] vs. 7.64 [5.83-11.00], 1st tertile, and 6.21 [3.20-8.31], 3rd tertile, p = 0.019). In pooled groups, we proved negative correlation between MA and TAG (r = -0.3153, p = 0.045) and the link between FR and FA composition of TAG expressed as positive relationship of FR with content of stearic acid (p < 0.001) and negative correlation with some n-6 polyunsaturated fatty acids (18:3n-6, p < 0.05, 22:5n-6, p < 0.01). Conclusion: The composition of FA in TAG molecules has undoubtedly some relationship to the FR generation. However, the other factors seem to play a role, since the relationship is not straightforward within entire FR range., and Vecka M., Tvrzická E., Votruba M.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
450. The significance of (CA)n tandem repeat in GABA(A) Beta‑3 subunit gene in tinnitus manifestation
- Creator:
- Rottenberg, Jan, Zallmann, M., Kostřica, Rom, Jurajda, Michal, and Talach, Tomáš
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, práce podpořená grantem, and TEXT
- Subject:
- tinnitus--diagnóza--genetika, evokované potenciály sluchové--fyziologie--genetika, receptory GABA-A--fyziologie--genetika, mozkový kmen--fyziologie, polymorfismus jednoho nukleotidu--genetika, genotyp, koncové repetitivní sekvence--genetika, sluchový práh--fyziologie, audiometrie čistými tóny--využití, akustická stimulace--metody, sluchové dráhy--fyziologie, dospělí, staří, ženské pohlaví, lidé, mužské pohlaví, and lidé středního věku
- Language:
- Czech and English
- Description:
- Cíl studie: Cílem studie bylo zjištění vztahů mezi manifestací tinnitu, nálezem na sluchových evokovaných potenciálech a genetickým pozadím u receptoru pro gamaaminomáselnou kyselinu typu A (GABA(A) receptor), podporující desinhibiční hypotézu vzniku tinnitu. Soubor a metodika: Bylo vyšetřeno 131 pacientů z hlediska sluchové ztráty, provedena kvantifikace tinnitu, sluchové evokované potenciály střední latence (MLR) a kmenové sluchové evokované potenciály (BAEP) a dále stanovení genotypu (CA)n repetitivní sekvence pro beta‑3 podjednotku GABA(A) receptoru. Následně byly hledány vztahy mezi jednotlivými výsledky a manifestací tinnitu. Výsledky: Byla nalezena korelace tinnitus skóre s amplitudovým poměrem vln V/III v BAEP (R = 0,22, p < 0,001) a s průměrným sluchovým prahem (R = 0,22, p = 0,17). Rovněž byla nalezena korelace tinnitus skóre s amplitudou vlny PA v MLR (R = 0,31–0,37; p < 0,001). Výsledky MLR neukázaly žádný vztah k průměrnému sluchovému prahu. U skupiny s kratší anamnézou tinnitu (méně než devět měsíců) byl prokázán rozdíl v manifestaci tinnitu na genotypu pro (CA)n repetitivní sekvenci genu pro beta‑3 podjednotku GABA(A) receptoru (p = 0,002). Tento výsledek byl rovněž konzistentní s rozložením amplitudy vlny PA v dané subpopulaci. Závěr: Tyto výsledky svědčí o existenci dvou hlavních regulačních mechanizmů vzniku tinnitu: první, který je závislý na velikosti sluchové ztráty, je na úrovni mozkového kmene, zatímco druhý je na úrovni korové s možnou souvislostí s genotypem (CA)n repetitivní sekvence pro beta‑3 podjednotku GABA(A) receptoru., Study aim:Study objective was to explore associations between manifestation of tinnitus, auditory evoked potentials and genetic background of gamma‑aminobutyric acid type A (GABA(A) receptors) to support the disinhibited feedback hypothesis of tinnitus generation. Materials and methods: A population of 131 patients was assessed for severity of hearing loss, quantification of tinnitus, mid‑latency responses (MLR) and brainstem auditory evoked potentials (BAEP), and (CA)n tandem repeat polymorphism in GABA(A) Beta‑3 subunit gene to establish any correlation with manifestation of tinnitus. Results: It was observed that tinnitus score correlates with V/III amplitude ratio in BAEP (R = 0.22, p < 0.001) and with mean pure tone audiometry (PTA) threshold (R = 0.22, p = 0.017). Analysis of the MLR results showed a significant correlation between the PA wave amplitude and the tinnitus score (R = 0.31–0.37; p < 0.001). MLR result analysis showed no statistically significant correlation between the wave amplitudes and the mean auditory threshold. An analysis of a subgroup with shorter clinical history (less than nine months) revealed a statistically significant difference in the tinnitus score in relation to the genotype of (CA)n tandem repeat of the GABRß3 receptor subunit gene (p = 0.002). This result was also consistent with the distribution of the PA wave amplitude in the given subpopulation. Conclusion: Our findings indicate existence of two main regulatory mechanisms of tinnitus generation: first, the brainstem mechanism is dependent on the severity of the hearing loss; second, the cortical mechanism is likely to be dependent on the genotype of (CA)n tandem repeat in GABA(A) beta‑3 subunit gene., and J. Rottenberg, M. Zallmann, R. Kostrica, M. Jurajda, T. Talach
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