[Zinc induces normoxic accumulation of transcriptionally active hypoxia-inducible factor 1-alpha in mammary epithelial cells]

Both zinc and the α-subunit of hypoxia-inducible factor (HIF-1α) play important roles in the remodelling of mammary gland tissues. In the present study, we examined the level and the transcriptional activity of HIF-1α in mammary cells upon zinc treatment. In MCF-7 mammary adenocarcinoma and MCF-10A mammary epithelial cell lines, the toxicity levels of zinc differ. Interestingly, both cell lines overexpress HIF-1α following zinc treatment. As it was evident from an up-regulation of its specific target gene CA9 that encodes carbonic anhydrase IX, the stabilized HIF-1α translocated to the nucleus and was transcriptionally active. Hence, we conclude that zinc causes normoxic accumulation of transcriptionally active HIF-1α by interfering with its post-translational regulation.

Perceptions and Attitudes Towards HIV/AIDS Patients among General Public in Bahrain

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Genetische Veränderungen des Protein-C-Systems

Das Protein-C-System umfaßt neben dem Protein C (PC) das Protein S (PS) sowie Thrombomodulin (TM). Obwohl das PC bereits im Jahr 1976 isoliert und charakterisiert wurde, wurde familiärer PC-Mangel erst im Jahr 1981 mit familiärer Thrombophilie in Zusammenhang gebracht. Heute wissen wir, daß PC einen der wichtigsten Inhibitoren der Gerinnung repräsentiert. Zur Umwandlung des Zymogens PC durch Thrombin in aktiviertes PC (APC) ist das TM von essentieller Bedeutung. Dieses Protein wurde 1981 entdeckt und danach intensiv in seiner biochemischen Funktion studiert. Die klinische Relevanz von TM-Defekten ist allerdings bis heute unklar. APC inaktiviert proteolytisch die aktivierten Gerinnungsfaktoren Faktor V (FVa) und Faktor VIII (FVIIIa). Zur Entfaltung der vollen Aktivität benötigt PC einen Kofaktor, das PS. Ein Mangel von PS führt zu erhöhter Thromboseneigung. Eine häufig vorkommende Mutante des Faktor V (FV), der FV-Leiden, kann durch APC nur unzureichend inaktiviert werden und ist ebenfalls mit erhöhter Thromboseneigung assoziiert. Der genaue Mechanismus über den FV-Leiden zu einem erhöhten Thromboserisiko beiträgt wird derzeit noch kontrovers diskutiert. Heute sind die biochemischen Interaktionen der Komponenten des PC-Systems recht genau untersucht und viele zugrundeliegende Mutationen aufgeklärt. Darüber hinaus gibt es recht umfangreiche Studien an großen Patientenkollektiven, in denen die Auswirkungen der Mutationen in den einzelnen Komponenten des PC-Systems auf das Thromboserisiko analysiert wurden. Die Ergebnisse mehrerer Evaluierungen werden in diesem Artikel zusammengefaßt.

Self-esteem links with anxiety and depression at one community adolescent sample

Introduction

Anxiety and depression is becoming an increasingly important public health issue. The adolescents’ population is among affected seriously.

Objectives

The objectives of the study was to investigate the level of anxiety, depression and self-esteem among adolescents and explore links between.

Methodology

Participants were 99 adolescents randomly selected in school, aged between 12 to 19 years (M = 14.88; SD = 2.09); in terms of gender composition, there were girls 41.1% and boys 58.9%. The measures used included the Albanian versions of depression self-rating scale for children, the revised children's manifest anxiety scale, and the rosenberg self-esteem scale. All data has been analysed by SPSS 21 and Excel 2007.

Results

Results showed that clinical significant levels reported 10.3% of participants for anxiety and 22.4% for depression. With low self-esteem scored 16.3% of participants. Self-esteem is significantly negatively correlated only with depression (r = -.433, P < .00). Mann-Whitney Test didn’t found significant differences in anxiety based on self-esteem levels. Mann-Whitney Test found significant differences in depression levels based on levels of self-esteem (Mdlowself-esteem = 15; n = 16; Mdnormalself-esteem = 10; n = 81) as adolescents with low self-esteem had significantly higher depression as compared to adolescents with normal self-esteem (z = -2.876, P < .004).

Conclusions

Findings suggested that self-esteem and depression links are present but not links self-esteem and anxiety. It is important to investigate these relationships in future research aimed identification/interventions programs.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Cation-Exchange Properties of Aluminium(III) Phosphate

Potentiometric titrations of aluminium(III) phosphate have been performed in the presence of aqueous electrolyte solutions containing Cu2+, Zn2+, Ni2+ and K+ ions as a function of the concentration of the latter, the pH and the temperature. The sorption of Zn2+ ions has also been studied and the data for metal ion sorption shown to correlate with the Potentiometric titration data, indicating that the process responsible for metal ion uptake is ion exchange. The pKa value of the exchanger and its thermodynamic parameters have been evaluated.

Exchange of Some Divalent Metal Cations and Their Effect on the Dissociation of Iron(III) Phosphate

Potentiometric titrations of iron(III) phosphate have shown an apparently weak monobasic acid behaviour towards alkali, alkaline earth and divalent transition metal ions. The selectivity sequence and dissociation of the exchanger was found to increase in the order Cu2+ > Zn2+ > Ni2+ > Ca2+ > K+. The dissociation constants of iron(III) phosphate have been determined from Potentiometric titration data in the temperature range 303–323 K. In addition, the exchange of Cu2+, Zn2+ and Co2+ on iron(III) phosphate and the effect of these ions on dissociation were also studied as a function of concentration, temperature and solution pH value. The thermodynamic parameters ΔH0, ΔS0 and ΔG0 for the dissociation of iron(III) phosphate are also presented.

Temperature and pH Effect on the Sorption of Divalent Metal Ions by Silica Gel

The sorption of Zn2+, Ni2+ and Cd2+ ions by silica gel was studied as a function of ion concentration, pH and temperature. An increase in all three parameters led to an increase in the extent of sorption for all the metal cations studied. The selectivity of the solid was observed to be in the order Zn2+ > Ni2+ > Cd2+. Sorption of the metal cations was accompanied by the release of H+ ions into the bulk phase. On average two moles of H+ ions were released per mole of metal cation sorbed. The sorption data fitted the linear forms of both the Kurbatov and Langmuir adsorption equations. The values of the binding constants were used to estimate the apparent thermodynamic parameters, ΔH and ΔS, for the adsorption process. FT-IR spectroscopic studies also showed that the uptake of metal cations by the silica gel occurred via a cation-exchange process.

Sorption of Metal Ions on a Mixed Oxide [0.5 M SiO2:0.5 M Fe(OH)3]

The sorption of Zn2+, Ni2+, Cd2+, Ca2+ and Mg2+ ions on to a mixed oxide of iron and silicon was found to increase with increasing temperature, concentration and pH of the system. The selectivity of this mixed oxide was Cd2+ ≥ Zn2+ ≥ Ni2+ > Ca2+ > Mg2+, indicating that the mixed oxide was more selective as an exchanger towards Cd2+ ions relative to its components, SiO2 and Fe(OH)3. The sorption data fitted the linear forms of the Kurbatov and Langmuir adsorption equations. The sorption of metal cations was accompanied by the release of H+ ions to the bulk phase. On average 1 mol H+ was released for every cation sorbed. The values of the binding constants were used to estimate the apparent thermodynamic parameters, ΔH and ΔS. The phenomenon of enthalpy/entropy compensation showed that the adsorption of metal ions by the mixed oxide occurred typically through a cation-exchange mechanism.

Cation-Exchange Properties of CrPO4

Alkali metal ion exchange (Li+, Na+ and K+) on chromium phosphate (CrPO4) was studied potentiometrically as a function of temperature and metal ion concentration. The shift in the potentiometric titration curves corresponding to the exchange of alkali metal cations increased with increasing pH and concentration of the metal ions, while the opposite results were obtained by increasing the temperature of the system. The affinity of the exchanger for alkali metal ions was also found to be in the order Li+ > Na+ > K+. The data were employed to evaluate the apparent deprotonation constants of CrPO4 and the corresponding thermodynamic parameters ΔH0, ΔS0 and ΔG0.

Temperature Effect on the Surface Properties of ZnO(am)

The point of zero charge and surface acidity constants of zinc oxide were determined over the temperature range 293–323 K. Both the point of zero charge (pzc) and the surface acidity constants (pKa1 and pKa2) were found to decrease with increasing temperature. The values of the dissociation constants (pKa1 and pKa2) determined from the Henderson-Hasselbach equation agreed very well with those determined using the Gaines-Thomas equation. The thermodynamic parameters ΔH0 and ΔS0 for the processes were also evaluated.

The role of TWEAK/Fn14 signaling in the MPTP-model of Parkinson's disease

The tumor necrosis factor like weak inducer of apoptosis (TWEAK) and its receptor, fibroblast growth factor-inducible 14 (Fn14), mediate inflammation and neuronal apoptosis in cerebral edema, ischemic stroke and multiple sclerosis. The downstream effectors and pathways linked to TWEAK-Fn14 signaling are strongly implicated in the pathology of Parkinson's disease (PD), thus indicating a putative role for TWEAK/Fn14 signaling in PD neurodegeneration. Using the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model, we aimed to determine whether genetic ablation or pharmacologic mitigation of the TWEAK protein and its Fn14 receptor affected substantia nigra and striatum Parkinsonian pathology. Changes in endogenous TWEAK protein expression were also quantified in tissue from both MPTP-treated mice and PD human samples. TWEAK protein expression was transiently increased in the striatal tissue but remained unaltered in substantia nigra tissue of MPTP-treated mice. There was also no change of TWEAK protein levels in the substantia nigra or the striatum of human PD patients as compared to matched control subjects. Mitigating the effects of endogenous TWEAK protein using neutralizing antibody did affect MPTP-mediated neurotoxicity in the substantia nigra using the sub-acute model of MPTP (30mg/kg i.p. over five consecutive days). Neither TWEAK nor Fn14 genetic ablation led to attenuation of MPTP-toxicity in the acute model. These findings suggest that TWEAK signaling might be an aspect of MPTP-mediated neuropathology and be involved in the overall neurodegenerative pathology of PD.