Lipotropismus von Coxsackie-Virus (Typ B-1) bei ausgewachsenen weißen Mäusen

Zusammenfassung Im braunen Fettgewebe ausgewachsener und hormonal nicht beeinflußter Mäuse findet eine frühzeitige und intensive Vermehrung von Coxsackie-Virus B- 1 (Stamm KLÍ und CONN- 5) statt. Auf die Bedeutung dieses Befundes für den Mechanismus der Coxsackie-Infeklion der weißen Maus wird hingewiesen.     

Clinical utility of selected disease activity markers in patients with systemic lupus erythematosus

The objective of this study was to assess the utility of measurement of thrombomodulin, antinucleosome antibodies, sVCAM-1, sICAM-1, neopterin, fas ligand, IL-10 and sIL-2R in patients with systemic lupus erythematosus (SLE) and to compare them with traditional markers of SLE activity (anti-dsDNA antibodies, C3, C4) and the ECLAM index of disease activity. The measurement was performed over a 6-month period at three consecutive time points after 3 months in each of the 52 patients with SLE. Anti-dsDNA antibodies, thrombomodulin, antinucleosome antibodies, sVCAM-1m sICAM-1, neopterin, fas ligand, IL-10 and sIL-2R were tested by ELISA technique, while C3, C4 components of complement were tested by nephelometry. Fas ligand and IL-10 did not correlate with the ECLAM index. The rest of the markers showed significant correlation with the disease activity index. Thrombomodulin and anti-dsDNA antibodies reflect in the best way the changing trend in disease activity. Antinucleosome antibodies seem to be a promising marker useful in early diagnosis. Soluble VCAM-1, sICAM-1, neopterin and sIL-2R are interesting molecules with a role in disease pathogenesis, but their practical utility is limited. Received: 27 September 2000 / Accepted: 31 March 2001     

Vitamin D metabolism

Vitamin D is the collective name for cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2), which are precursors of hormones with an important role in regulation of the metabolism of calcium and phosphates. This review article describes the production of vitamin D3 in the skin by ultraviolet radiation from sunlight, transport of vitamin D and its metabolites in blood, formation of the active hormonal form - calcitriol (1,25-dihydroxyvitamin D) by hydroxylation in the liver and kidney, and termination of the action by catabolism to inactive metabolites.     

Follicular fluid levels of anti-Müllerian hormone,insulin-like growth factor 1 and leptin in women with fertility disorders

Anti-Müllerian hormone (AMH), insulin-like growth factor 1 (IGF1) and leptin are produced in the granulosa cells of follicles and play an important role in the growth and maturation of follicles. The aim of our study was to monitor AMH, IGF1 and leptin levels in a group of healthy women and compare them to a group of women with fertility disorders. The second aim was the evaluation of biomarker levels in relation to the identified cause of infertility. Totally, 146 females were enrolled into our study. Seventy-two healthy controls and seventy-four females with fertility disorders were divided into four subgroups: anovulation, endometriosis, fallopian tube damage, unknown reason. IGF1 was the only biomarker with significantly lower levels throughout the entire group with fertility disorders. We did not identify any statistically significant differences for AMH and leptin. Regarding subgroups, significant differences were only observed in the group of anovulatory women. AMH and leptin showed higher levels while IGF1 showed lower levels. In conclusion, levels of AMH, IGF1 and leptin found in follicular fluid are sensitive markers for anovulatory fertility disorders. AMH, IGF1 and leptin levels in follicular fluid have no relation to the fertility disorders caused by endometriosis, fallopian tube damage or disorders with unknown etiology.

Abbreviations: AMH: anti-Müllerian hormone; IGF1: insulin-like growth factor 1; PCOS: polycystic ovary syndrome     

Oxidative stress-mediated cytotoxicity and metabolism of T-2 toxin and deoxynivalenol in animals and humans: an update

Trichothecenes are a large family of structurally related toxins mainly produced by Fusarium genus. Among the trichothecenes, T-2 toxin and deoxynivalenol (DON) cause the most concern due to their wide distribution and highly toxic nature. Trichothecenes are known for their inhibitory effect on eukaryotic protein synthesis, and oxidative stress is one of their most important underlying toxic mechanisms. They are able to generate free radicals, including reactive oxygen species, which induce lipid peroxidation leading to changes in membrane integrity, cellular redox signaling, and in the antioxidant status of the cells. The mitogen-activated protein kinases signaling pathway is induced by oxidative stress, which also induces caspase-mediated cellular apoptosis pathways. Several new metabolites and novel metabolic pathways of T-2 toxin have been discovered very recently. In human cell lines, HT-2 and neosolaniol (NEO) are the major metabolites of T-2 toxin. Hydroxylation on C-7 and C-9 are two novel metabolic pathways of T-2 toxin in rats. The metabolizing enzymes CYP3A22, CYP3A29, and CYP3A46 in pigs, as well as the enzymes CYP1A5 and CYP3A37 in chickens, are able to catalyze T-2 toxin and HT-2 toxin to form the C-3′–OH metabolites. Similarly to carboxylesterase, CYP3A29 possesses the hydrolytic ability in pigs to convert T-2 toxin to NEO. T-2 toxin is able to down- or upregulate cytochrome P-450 enzymes in different species. The metabolism of DON in humans is region-dependent. Free DON and DON-glucuronide are considered to be the biomarkers for humans. The masked mycotoxin DON-3-β-d-glucoside can be hydrolyzed to free DON in the body. This review will provide useful information on the progress of oxidative stress as well as on the metabolism and the metabolizing enzymes of T-2 toxin and DON. Moreover, the literature will throw light on the blind spots of metabolism and toxicological studies in trichothecenes that have to be explored in the future.     

Comparison of Testing Methods for Evaluating the Resistance of Alkali-Activated Blast Furnace Slag Systems to Sulfur Dioxide

Alkali-activated systems (AAS) represent an ecologically and economically sustainable inorganic binder as an alternative to ordinary Portland cement (OPC). One of the main benefits of AAS is their durability in aggressive environments, which can be equal or even better than that of OPC. In this paper, the influence of the type of alkaline activator in alkali-activated blast furnace slag (AAS) in terms of resistance to sulfur dioxide corrosion was investigated. The durability testing process was based on the CSN EN ISO 3231 standard and simultaneously compared with mortar samples prepared by using Blastfurnace cement CEM III/A 32.5R. The degradation progress was evaluated by employing several different methods such as observing the compressive strength development, weight change evaluation, non-destructive testing methods like ultrasound or impact echo technique, or visual phenolphthalein technique. Subsequently, fundamental characterization of samples by the XRD method was performed during the degradation test. The obtained results indicate that none of the testing methods used could be prioritized over others to determine the resistance of AAS against the action of sulfur dioxide. For this reason, the durability testing of AAS remains an issue, and the development of specific standards considering the behavior of AAS seems necessary.