Inherited disturbances of the mitochondrial energy generating system represent a heterogeneous group of disorders associated with a broad spectrum of metabolic abnormalities and clinical symptoms. We used the polarographic and spectrophotometric method for detection of mitochondrial disorders, because these two techniques provide a different insight into mitochondrial function. In six patients suspected of mitochondrial disease we found defects of complex I (two patients), complex III (one patient), complex IV (two patients) and a combination of defect of complex III and IV (one patient). Citrate synthase activity, used as the reference enzyme, was not changed. A comparison of the two methods showed several differences in evaluation of mitochondrial enzymes activity due to the fact that both methods used different conditions for enzyme activity measurements. In contrast to oxygen consumption measurements, where the function of the whole-integrated respiratory chain is characterized, spectrophotometric measurements characterize activities of isolated complexes in disintegrated membranes. However, it may be concluded from our experiments that both methods provide useful and complementary data about mitochondrial energetic functions. Whereas spectrophotometric data are suitable for evaluation of maximal enzyme activities of mitochondrial enzyme complexes, polarographic data provide better information about enzyme activities in cells with mitochondrial defects under in situ conditions., L. Wenchich, Z. Drahota, T. Honzík, H. Hansíková, M. Tesařová, J. Zeman, J. Houštěk., and Obsahuje bibliografii
Benzén má hematotoxické účinky, poškodzuje centrálnu nervovú sústavu a imunitný systém, je karcinogénom kategórie 1 a mutagénom kategórie 2. Expozícia benzénu je limitovaná hygienickými predpismi. V súbore 99 pracovníkov exponovaných benzénu a 19 neexponovaných (kontrolná skupina) boli v moči stanovené dva biomarkery benzénovej expozície rôznymi analytickými metódami. Kyselina trans,trans-mukonová bola stanovená chromatograficky a fenol spektrofotometricky. Cieľom štúdie bolo porovnať mieru ich vylučovania v oboch sledovaných skupinách a dokázať vhodnosť chromatografického stanovenia kyseliny trans,trans-mukonovej v moči ako rýchly a spoľahlivý biomonitoring pracovného prostredia. Priemerná koncentrácia fenolu v oboch skupinách sa pohybovala na fyziologickej úrovni. V skupine exponovaných benzénu bola priemerná koncentrácia fenolu vyjadrená ako Priemer (SD) 11,07 (8,51) mg.g-1 kreatinínu, v kontrolnej skupine bola 12,16 (11,42) mg.g-1 kreatinínu. Priemerná koncentrácia kyseliny trans,trans-mukonovej exponovaných pracovníkov bola 0,64 (0,95) mg.g-1 kreatinínu, v porovnaní s kontrolnou skupinou 0,29 (0,24) mg.g-1 kreatinínu, jej obsah v moči exponovaných pracovníkov nepresahoval doporučenú hodnotu koncentračného limitu pre úroveň technickej smernej hodnoty benzénu v zmysle legislatívy platnej v SR, ale prekračoval doporučenú biologickú medznú hodnotu podľa Americkej rady vládnych hygienikov pre priemysel. Štatisticky t-testom bol potvrdený signifikantný rozdiel v nameraných hodnotách vylučovanej kyseliny trans,trans-mukonovej medzi kontrolnou skupinou pacientov a pracovníkov exponovaných benzénu, dokazujúci vhodnosť jej stanovenia ako rýchly a spoľahlivý biomonitoring pracovného prostredia., Benzene has hematoxic effects, causes damage to the central nervous system and immune system, is classified as a Category 1 carcinogen, and a Category 2 mutagen. Benzene exposure is limited by public health legislation. A total of 99 biological samples of benzene-exposed workers and 19 biological samples of non-exposed patients in a control group were examined. Concentration determination of two selected biomarkers of benzene exposure was performed using two different analytical methods. Trans,transmuconic acid was determined by chromatography and phenol was determined by spectrophotometry. The purpose of the study was to compare their excretion rate in both monitored groups, and to prove appropriateness of chromatographic determination of trans,trans-muconic acid in urine for quick and reliable biomonitoring of the working environment. The average phenol concentration in both groups varied at physiological levels: mean (SD) was 11.07 (8.51) mg.g-1 creatinine for a benzene-exposed group, and 12.16 (11.42) mg.g-1 creatinine for a control group. As for trans,trans-muconic acid, the average concentration was 0.64 (0.95) mg.g-1 creatinine in case of benzene-exposed workers compared to 0.29 (0.24) mg.g-1 creatinine for a control group. Concentration of trans,trans-muconic acid in urine from exposed workers did not exceed a recommended concentration limit for Threshold Limit Value level for benzene, but exceeded a recommended Biological Exposure Indices value set by the American Conference of Governmental Industrial Hygienists. A statistic t-test revealed a significant difference in measured values of excreted trans,transmuconic acid between a control group of patients and benzene-exposed workers proving appropriateness of determination for quick and reliable bio-monitoring of the working environment., Ivica Bajusová, Peter Kolarčik, Michal Ihnatko, Tatiana Kimáková, Ľubomír Legáth, and Literatura Ivica Bajusová, Peter Kolarčik, Michal Ihnatko, Tatiana Kimáková, Ľubomír Legáth: Porovnanie miery vylučovania vybraných biomarkerov expozície benzénu. Hygiena, 2013, roč. 58, č. 2, str. 70-74.