Quantitative analysis of transforming growth factor beta isoforms mRNA in the human corneal epithelium.

TGF-beta is an important mediator of cell growth, differentiation, and proliferation and plays a significant role in both normal and pathological corneal tissue. However, the quantitative relations between TGF-beta1, -beta2 and -beta3 isoforms in human cornea still remain unclear. Therefore, the aim of this study was to determine the gene expression profile of TGF-betas in order to evaluate quantitative relations between the examined transcripts in human corneal epithelium. Transcriptional activity of TGF-beta1, 2, 3, GAPDH and beta-actin genes was estimated on the basis of mRNA copy number per 1 microg of total RNA using the real-time QRT-PCR technique with the SYBR Green I chemistry. Specificity of RT-PCR reaction was confirmed by determination of the characteristic melting temperature for each amplimer. Additionally, the RT-PCR products were separated on 6% polyacrylamide gels and visualized with silver salts. Expression of all TGF-beta genes for the corneal epithelium was determined. Comparable analysis of mRNA copies/1 mug of total RNA for each TGF-beta isoform showed that: TGF-beta1 > TGF-beta2; TGF-beta3 > TGF-beta2; TGF-beta1 = TGF-beta3 (ANOVA test P < 0.0001; post-hoc Tukey's test: TGF-beta1 and TGF-beta2, P = 0.0306; TGF-beta3 and TGF-beta2, P = 0.0045; TGF-beta1 and TGF-beta3 NS). We found different expression of the TGF-beta1, -2 and -3 isoforms in the human corneal epithelium. Such differential expression of TGF-betas suggests that each of them may play a specific role in corneal tissue.

Goal orientations and attitudes toward doping.

The aim of the study was to determine if there is a relationship between attitudes toward doping and achievement goal orientations of athletes. Questionnaires from 830 athletes (including 263 females) were obtained. Athletes declared moderately positive attitudes, with attitude toward anti-doping controls as the strongest and attitude toward sanctions as the weakest. Females declared significantly more favourable attitudes than males. With respect to the relationship between goal orientations and attitudes toward doping, it was found that athletes who were high task/low ego oriented declared the most favourable attitudes, while athletes who were low task/high ego oriented declared the least favourable attitudes. Multiple regression analyses confirmed that ego orientation was significantly negatively related to, and task orientation was significantly positively related to attitudes toward doping. It means that with the increase in task orientation, attitudes toward doping became more favourable. The opposite can be said about the increase in ego orientation. It could be argued then, that creating a motivational climate which promotes task orientation (mastery climate) may aid anti-doping efforts.

Thermally excited multiplet states in macerals separated from bituminous coal

Electron paramagnetic resonance searches of thermally excited multiplet states in macerals, exinite, vitrinite, and inertinite of Polish medium-rank coal (85.6 wt% C), were performed. Numerical analysis of lineshape indicates a multicomponent structure of the EPR spectra of macerals heated at 300 degrees and 650 degrees C. EPR spectra of exinite and vitrinite are a superposition of broad Gauss, broad Lorentz (Lorentz 1), and narrow Lorentz (Lorentz 3) lines. Two narrow Lorentz (Lorentz 2 and Lorentz 3) lines were observed in the resonance absorption curves of inertinite. The influence of the measuring temperature (100-300 K) on the EPR lines of the macerals was also studied. The experimentally obtained temperature dependence of the EPR line intensities were fitted by the theoretical functions characteristic for paramagnetic centers with ground doublet state (S = 12) and paramagnetic centers with thermally excited triplet (S = 1) and quadruplet (S = 32) states. Thermally excited multiplet states were found in exinite and vitrinite. Both paramagnetic centers with doublet ground state (S = 12) and paramagnetic centers with thermally excited states, probably quadruplet states (S = 32), exist in the group of paramagnetic centers of exinite and vitrinite with the broad Lorentz 1 lines. Intensities (I) of the broad Gauss and the narrow Lorentz 3 lines of exinite and vitrinite changes with temperature according to the Curie law (I = C/T). The existence of thermally excited multiplet states was not stated for inertinite. The two groups of paramagnetic centers of inertinite with Lorentz 2 and Lorentz 3 lines obey the Curie law. Copyright 2000 Academic Press.

The effect of endo- and exogenous melanin on Zn2+ and Co2+ elimination and distribution in mice.

The content of endogenous melanin in white Balb c and black C-57 Bl. mice affected Zn2+ and Co2+ accumulation, elimination and distribution following intraperitoneal administration of these ions. Elimination of Co2+ ions was significantly greater in white mice than in black mice. Accumulation of Zn2+ was higher than that of Co2+ and did not depend on melanin content in mice. The same response was observed upon administration of exogenous melanin. Both ions accumulated mainly in spleen and heart irrespective of melanin content.