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Biomedical subjects

J Jarkovský

Publications and source records attributed to J Jarkovský.

13 recordsLinked to original sources
PubMed2006

Philometra ovata (Nematoda: Philometroidea): a potential sentinel species of heavy metal accumulation.

To assess the bioindicator value of parasites, the concentrations of six heavy metals (Cr, Cu, Pb, Cd, Ni and Zn) were analyzed by atomic absorption spectrometry in gravid females of the nematode Philometra ovata, body cavity parasites of gudgeon (Gobio gobio) and muscle samples of infected and uninfected hosts. The concentration of heavy metals was significantly higher in specimens of P. ovata compared to the host muscle tissue. The parasite-to-muscle ratio of heavy metals varied from 3.2 to 121.7, in increasing concentrations for Cr, Cd, Cu, Pb, Ni and Zn. The presence of parasites did not influence the heavy metal content of the hosts, and no significant differences were found between muscle tissues of parasitized and non-parasitized fishes. The bioconcentration factor (BF = Cparasite/Csediment)varied between 0.4 and 25.8, in increasing order for Cd, Zn, Cu, Pb, Ni and Cr. These results indicate that P. ovata may serve as sensitive indicator species of heavy metal pollution in freshwater ecosystems.

Animals↗
PubMed2006

Raltitrexed plus oxaliplatin in the second-line treatment of metastatic colorectal cancer.

The primary endpoint of this study was to evaluate the efficacy (objective response rate; ORR) of combined chemotherapy with raltitrexed plus oxaliplatin as second-line treatment in patients with metastatic colorectal cancer (CRC). Secondary endpoints were overall survival (OS), time to progression (TTP) and toxicity (NCI-CTC criteria). The target population were patients with metastatic colorectal adenocarcinoma who progressed after first-line chemotherapy. Treatment consisted of raltitrexed 3 mg/m2 as a 15-minute intravenous (IV) infusion followed 45 minutes later by oxaliplatin 130 mg/m(2) IV as a 2-h infusion on Day 1, repeated every 3 weeks until further disease progression (PD), unacceptable toxicity or the decision of the patient. A total of 51 patients, all with WHO performance status 0-2 received a median of 6 treatment cycles (range 1-11). After 3 cycles, 8 of the 47 evaluable patients (17%) had experienced an ORR, 28 patients (59.6%) had experienced stable disease (SD) and 11 patients (23.4%) had PD. After 6 cycles, 1 of the 29 evaluable patients (3.5%) had an ORR, 13 patients (44.8%) had SD and 15 patients (51.7%) had PD. After a median follow-up of 48.9 weeks, median TTP was 18 weeks and median overall survival was 54.4 weeks. Treatment was well tolerated; grade 3 toxicities occurred in only 5/51 patients (9.8%). The most common toxicities were paraesthesia (62.7%), diarrhoea (23.5%), nausea (41.2%), vomiting (33.3%), hepatotoxicity (25.5%), and hematological toxicity (41.2%). In conclusion, the combination of oxaliplatin plus raltitrexed appears to be effective and well tolerated as second-line therapy in patients with disseminated CRC.

Adenocarcinoma↗
PubMed2005

Seasonal occurrence and metrical variability of Gyrodactylus rhodei Zitnan 1964 (Monogenea, Gyrodactylidae).

The seasonal dynamics of Gyrodactylus rhodei, a monogenean ectoparasite of bitterling (Rhodeus sericeus), was studied from June 2000 to May 2001 in the Kyjovka River, Czech Republic. A negative relationship between prevalence and intensity of infection of G. rhodei and water temperature was found. Metrical variability of the hard parts of the parasite haptor was studied throughout the sampling season. A negative relationship between water temperature and the size of the hard parts of the G. rhodei haptor was evident in the measurements of the total length of the marginal hooks, the sickle length of marginal hooks, anchors, anchor point and root, the width of the ventral bar and the membrane processes. Sequences of the partial ITS (rDNA) of specimens collected during the cold and warm seasons were analysed. Sequences of all studied parasite specimens were identical and there was no evidence of intraspecific variability in the sequenced region.

Animals↗
PubMed2005

Bioaccumulation of mercury in muscle tissue of fish in the Elbe River (Czech Republic): multispecies monitoring study 1991-1996.

The study monitored mercury (Hg) contamination of fish muscle tissue at 13 geographical sites that can be regarded as crucial points for an ecotoxicological assessment of the Czech Republic section of the Elbe River. The descriptive part of the study was primarily aimed at comparative evaluation of the Hg load during the period 1991-1996. The conclusions were supported by multivariate statistical analyses of the content of Hg in the muscle tissue of 1251 fish belonging to 23 species with four dominant indicator species: Perca fluviatilis (n=163), Abramis brama (n=173), Rutilus rutilus (n=148), and Leuciscus cephalus (n=166). Considering data from 3- to 5-year-old fish, significantly increased contamination was detected in typical predators compared to the other fish species in all sites (P<0.001). On the other hand, omnivorous and planctivorous species were ranked as the least sensitive for Hg pollution. Perch appeared to be the most contaminated species in the sample with muscle Hg concentration in the range of 0.840-1.398 mg Hg kg(-1). Although less contaminated than perch, muscle contamination of bream sensitively separated differently contaminated sites; the highest load ranged from 0.368 to 0.543 mg Hg kg(-1). Time-related comparison of sampling campaigns revealed no significant trend changes, in either sediment samples or fish tissue. Thus, the analyses documented an evidently rather stabilized total Hg pollution in the Elbe River environment. Multivariate multispecies analyses found the age of analyzed individuals and the feeding strategy of a given species as the most important, however mutually interactive, covariates for Hg accumulation in muscle tissue. The analyses revealed decreasing sensitivity of older predator individuals to differentiate highly and moderately contaminated sites. Benthophagous species mostly kept their discrimination capacity toward contaminated sites in all age categories, with the exception of bream that was rather linked to the pattern typical for predator species. The unclear position of omnivorous species, represented namely by roach, corresponded with their weak bioindicator power, mainly in the young age categories.

Animals↗
PubMed2004

Seasonal dynamics of Proteocephalus sagittus in the stone loach Barbatula barbatula from the Hana River, Czech Republic.

The seasonal cycle of the cestode Proteocephalus sagittus (Cestoda: Proteocephalidae) was studied for the first time in the stone loach Barbatula barbatula from the Hana River, Czech Republic. A total of 180 loaches were examined monthly from January to December 2001. The parasite occurred in loaches throughout the year but infection parameters differed significantly among seasons, with the highest values of prevalence and abundance from the late winter to the early summer. Parasite recruitment took place in the winter and early spring and the worms sexually matured in the late spring and early summer. In contrast to P. torulosus, the gravid worms of which laid eggs only at the end of the spring/beginning of the summer, gravid worms of P. sagittus were also found, although in low numbers, in the autumn and early winter. The rate of infection of loach with P. sagittus was neither dependent on the sex nor on the size of its fish host.

Animals↗
PubMed1994

[New therapeutic activity in geriatric psychiatry].

The author mentions and describes in detail three dynamically oriented psychiatric activities which proved useful and became thus an important component of comprehensive treatment of demented patients. Part of the activating programme for patients with advanced affections of memory, orientation and concentrating capacity is Training in orientation and reality (TOR). Relaxation training (TR) helps patients to get rid of the sensation of tension, fear and uncertainty. Cognitive training (KT) helps to restore and improve cognitive functions. By means of the mentioned activities the authors reinforce persisting abilities and skills. In the conclusion the authors present recommendations which make the reader familiar with suitable communication with and treatment of clients suffering from organic brain affections.

Aged↗
PubMed1975

[Migration of leukocytes in late syphilis].

Following non-specific inflammation, greater numbers of mononuclears than polymorphonuclear leukocytes were found to migrate into a 'skin-window' in patients with late syphilis. This mononuclear preponderance was statistically significant, the normal control subjects showing a preponderance of polymorphonuclears.

Aged↗