MJERENJE UTJECAJA STAVOVA UČENIKA NA PROCES STJECANJA MATEMATIČKOG ZNANJA

In this paper the authors discuss the influence of students’ attitudes on the process and results of their studies. The procedure by which a grade for students’ attitudes is obtained is very simple, and the results are treated in several ways. A survey has been conducted among the students in elementary school in order to establish their attitude towards Mathematics lessons. By comparing the answers of students to their knowledge, results were obtained indicating that motivation derived from enjoyment in mathematics has a much greater influence than student consciousness about the usefulness of the subject. The reason for this difference lies in the fact that the application of most mathematical areas seems abstract to learners of this age.U ovom se radu proučava utjecaj stavova učenika na proces i rezultate učenja. Procedura kojom se dobiva ocjena stavova učenika je vrlo jednostavna, a rezultati su tretirani na nekoliko načina. Anketa je provedena među učenicima osnovne škole kako bi se utvrdio njihov stav prema nastavi matematike. Uspoređivanjem odgovora učenika s njihovim znanjem dobiveni su rezultati po kojima motivacija uzrokovana uživanjem u matematici ima mnogo veći utjecaj nego svijest o korisnosti predmeta. Ova razlika postoji zato što primjena matematike djeluje suviše apstraktno učenicima ove dob

Modulation of NCAM/FGFR1 signaling suppresses EMT program in human proximal tubular epithelial cells.

Neural cell adhesion molecule (NCAM) and fibroblast growth factor receptor 1 (FGFR1) cross-talk have been involved in epithelial-to-mesenchymal transition (EMT) process during carcinogenesis. Since EMT also contributes to maladaptive repair and parenchymal damage during renal fibrosis, we became encouraged to explore the role of NCAM/FGFR1 signaling as initiating or driving forces of EMT program in cultured human proximal tubular epithelial cells (TECs). TECs stimulated with TGF-β1 (10ng/mL) was used as an established in vitro EMT model. TGF-β1 downstream effectors were detected in vitro, as well as in 50 biopsies of different human kidney diseases to explore their in vivo correlation. NCAM/FGFR1 signaling and its modulation by FGFR1 inhibitor PD173074 (100nM) were analyzed by light microscopy, immunolabeling, qRT-PCR and scratch assays. Morphological changes associated with EMT appeared 48h after TGF-ß1 treatment and was clearly apparent after 72 hours, followed by loss of CDH1 (encoding E-Cadherin) and transcriptional induction of SNAI1 (SNAIL), SNAI2 (SLUG), TWIST1, MMP2, MMP9, CDH2 (N-Cadherin), ITGA5 (integrin-α5), ITGB1 (integrin-β1), ACTA2 (α-SMA) and S100A4 (FSP1). Moreover, at the early stage of EMT program (24 hours upon TGF-β1 exposure), transcriptional induction of several NCAM isoforms along with FGFR1 was observed, implicating a mechanistic link between NCAM/FGFR1 signaling and induction of EMT. These assumptions were further supported by the inhibition of the EMT program after specific blocking of FGFR1 signaling by PD173074. Finally, there was evidence for an in vivo TGF-β1 pathway activation in diseased human kidneys and correlation with impaired renal excretory functions. Collectively, NCAM/FGFR1 signaling appears to be involved in the initial phase of TGF-ß1 initiated EMT which can be effectively suppressed by application of FGFR inhibitor

The Effects of Potassium Channel Opener P1075 on the Human Saphenous Vein and Human Internal Mammary Artery

Because adrenergic contractions can contribute to the development of life-threatening spasm of coronary artery bypass graft, this study was performed to investigate the effect of adenosine 3-phosphate (ATP)-sensitive K(+) channel (K(ATP)) opener P1075 on contractions of isolated human saphenous vein (HSV) and human internal mammary artery (HIMA). Phasic contractions were evoked by electric field stimulation (20 Hz) and noradrenaline. The sustained contractions were evoked by phenylephrine. The presence of pore-forming Kir6.1 and Kir6.2 subunits of the K(ATP) channels in the HIMA and only Kir6.2 in the HSV was confirmed immunomorphologically. P1075 inhibited in the HSV only, the electrical field stimulation contractions more strongly than noradrenaline contractions. In addition, the phenylephrine contractions of HSV were more sensitive to P1075 in comparison to those of HIMA. Glibenclamide, a K(ATP) channel blocker antagonized the vasodilatation produced by P1075 in both grafts differently, because its effect was more prominent on the P1075-induced inhibition of contractions of HSV than of HIMA. We conclude that P1075 has a vasorelaxant effect and inhibited adrenergic contractions of the tested grafts. This effect is graft and vasoconstrictor selective and seems to be mediated by Kir6.1-and/or Kir6.2-containing K(ATP) channels. Thus, P1075 can be considered as a potential drug in the prevention of graft spasm