What Made Me the Teacher I Am Today? A Reflection by Selected Leonore Annenberg-Woodrow Wilson Teaching Fellows

The report offers a series of short essays from 18 teachers, each reflecting on what inspired and guided them into the teaching profession. Some of the highlights include:"I've come to realize that my learning process in the classroom actually feels a whole lot like the science I practiced at the bench: engineering experimental procedures, collecting and analyzing data, and formulating questions about next steps. It turns out that my scientific worldview can really improve learning outcomes for my students," said Kristin Milks, a biology and earth science teacher in Bloomington, IN, who enrolled in a teacher preparation program shortly after completing her Ph.D. in biochemistry."What transforms someone from being a good teacher to being a great teacher is the passion to make connections with students, to constantly evaluate and adjust their practice to do what is in the students' best interest," said Catherine Ann Haney, a Virginia Spanish teacher who has recently been teaching in Santiago, Chile."Enrolling in a teacher education program, instead of starting my career as a teacher first and then obtaining my master's degree after, meant I had a cohort of other soon-to-be teachers to learn with as we persevered through a very rigorous and demanding year," said Jeremy Cress, a math teacher in Philadelphia."I realized that being a good math teacher does not mean explaining clearly, making kids like me, or making math fun. Rather, it means giving students the opportunity to solve problems by themselves from start to finish, to struggle and persevere, and to learn from each other's particular strengths," said Brittany Leknes, a math teacher from Sunnyvale, CA."Together my students and I co-create their identities, their sense of themselves, and their understanding of their place in society. Because I believe wholly in my students' own power, I teach to disrupt school cultures that suggest that students need to be anything less than their whole selves," said Kayla Vinson, who taught social students in the Harlem Children's Zone.Created in 2007, the Leonore Annenberg-Woodrow Wilson Teaching Fellowship was designed to serve as the equivalent of a national "Rhodes Scholarship" for teaching. Working with Stanford University, the University of Pennsylvania, the University of Virginia, and the University of Washington, the Woodrow Wilson Foundation provided $30,000 stipends for exceptionally able candidates to complete a yearlong master's degree program. In exchange, the teacher candidates agreed to teach for three years in high-need secondary schools across the country. The Leonore Annenberg Teaching Fellowship was funded through grants from the Annenberg Foundation and Carnegie Corporation of New York. It served as the basis for the Woodrow Wilson Foundation's successful Teaching Fellowship program, which now operates in five states (Georgia, Indiana, Michigan, New Jersey, and Ohio), operating in partnership with 28 universities. Woodrow Wilson Teaching Fellows complete a rigorous yearlong master's degree program, coupled with a robust yearlong clinical experience. Once they earn their degrees, Woodrow Wilson Teaching Fellows teach in high-need STEM classrooms, while receiving three years of coaching and mentoring

The relationship of physicochemical properties and structure to the antioxidative activity of free amino acids in the aqueous Fenton system

Iron is essential for plant growth, metabolism of mitochondria and chloroplasts, and a wide assortment of enzymes. However, it is also involved in Fenton reaction that generates hydroxyl radical (HO•), the most reactive species in plants. The aim of our study was to examine the effects of amino acids on HO• production. The rank order according to antioxidative activity (AA) of amino acids in Fenton system was: Trp > Phe, Leu > Ile > His > Arg > Val > Lys, Tyr, Pro > Gln, Thr, Ser > Glu, Ala, Gly, Asn, Asp. Sulfur-containing amino acids generated different secondary reactive products, which were discriminated by EPR spin-trapping spectroscopy. AA showed positive correlation with hydrophobicity and negative correlation with polarity. HO•provoked oxidation of amino acids was strongly positively affected by hydrophobic hydration. Group contribution method showed that the reactivity of amino acids with HO• is defined by the properties of side-chains (the contribution of NH3+CHCOO− group and antioxidative activity of Gly were next to zero). Our results might shed a new light on the role of iron in the regulation of free amino acids pool and on protein oxidation in plants. According to our findings, native proteins (with exposed polar residues) might not be particularly susceptible to oxidation by HO•. But once a protein is damaged and partially denatured it exposes hydrophobic side-chains and might become a likely target for HO•, thus potentially acquiring an antioxidative role. Further research on change of redox properties of proteins with denaturation is warranted

Antioxidative Defense Enzymes in Placenta Protect Placenta and Fetus in Inherited Thrombophilia from Hydrogen Peroxide

Our aim was to investigate the activities of antioxidative defense enzymes in the placenta, fetal blood and amnion fluid in inherited thrombophilia. Thrombophilia was associated with nearly threefold increase of activity (p < 0.001) of the placental catalase (81.1 ± 20.6 U/mg of proteins in controls and 270.0 ± 69.9 U/mg in thrombophilic subjects), glutathione (GSH) peroxidase (C: 20.2 ± 10.1 U/mg; T: 60.0 ± 15.5 U/mg), and GSH reductase (C: 28.9 ± 5.6 U/mg; T: 72.7 ± 23.0 U/mg). The placental activities of superoxide dismutating enzymes—MnSOD and CuZnSOD, did not differ in controls and thrombophilia. Likewise, the activities of catalase and SOD in the fetal blood, and the level of ascorbyl radical which represents a marker of oxidative status of amniotic fluid, were similar in controls and thrombophilic subjects. From this we concluded that in thrombophilia, placental tissue is exposed to H2O2-mediated oxidative stress, which could be initiated by pro-thrombic conditions in maternal blood. Increased activity of placental H2O2-removing enzymes protects fetus and mother during pregnancy, but may increase the risk of postpartum thrombosis

The effects of wild-type and mutant SOD1 on smooth muscle contraction

In this work we compared the mutated liver copper zinc-containing superoxide dismutase (SOD1) protein G93A of the transgenic rat model of familial amyotrophic lateral sclerosis (FALS), to wild-type (WT) rat SOD1. We examined their enzymatic activities and effects on isometric contractions of uteri of healthy virgin rats. G93A SOD1 showed a slightly higher activity than WT SOD1 and, in contrast to WT SOD1, G93A SOD1 did not induce smooth muscle relaxation. This result indicates that effects on smooth muscles are not related to SOD1 enzyme activity and suggest that heterodimers of G93A SOD1 form an ion-conducting pore that diminishes the relaxatory effects of SOD1. We propose that this type of pathogenic feedback affects neurons in FALS

Comparison of the effects of methanethiol and sodium sulphide on uterine contractile activity

Background: Our aim was to investigate the effect of methanethiol (CH3SH) on contractility of rat uterus and activities of redox-active enzymes, and to compare them with the effect of sodium sulphide (Na2S), a hydrogen sulphide (H2S/HS-) donor. Methods: Uteri were isolated from virgin Wistar rats, divided into six groups, controls (untreated uteri allowed to contract spontaneously and in the presence of Ca2+(6 mM)), CH3SH treated (spontaneously active and Ca2+ induced) and Na2S treated (spontaneously active and Ca2+ induced). Underlying antioxidative enzyme activities (superoxide dismutase - SOD, glutathione peroxidase - GSHPx, glutathione reductase - GR) in CH3SH- or Na2S-treated uteri were compared to controls. Results: Our experiments showed that CH3SH and Na2S provoked reversible relaxation of both spontaneous and Ca2+ induced uterine contractions. The dose-response curves differed in shape, and CH3SH curve was shifted to higher concentration compared to H2S/HS-. The effects of Na2S fitted sigmoid curve, whereas those of CH3SH fitted linearly. CH3SH provoked increased SOD activity and decreased GR activity. However, Na2S (H2S/HS-) provoked an increase in SOD activity exclusively in Ca2+ stimulated uteri, while the activity of GSHPx was increased in both types of active uteri. Conclusion: Our results imply that CH3SH may have a constructive role in the control of muscle function and metabolism. Observed differences between CH3SH and H2S/HS- could be attributed to a larger moiety that is present in CH3SH compared to H2S, but they are more likely to be a consequence of the specific actions of HS-, in relation to its negative charge. (C) 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban \& Partner Sp. Z o.o.. All rights reserved.Ministry of Science and Technological Development of the Republic of Serbia {[}173014

Reactions of superoxide dismutases with HS-/H2S and superoxide radical anion: An in vitro EPR study

Interactions of hydrogen sulfide (HS-/H2S), a reducing signaling species, with superoxide dimutases (SOD) are poorly understood. We applied low-T EPR spectroscopy to examine the effects of HS-/H2S and superoxide radical anion (O-2(-)) on metallocenters of FeSOD, MnSOD, and CuZnSOD. HS-/H2S did not affect FeSOD, whereas active centers of MnSOD and CuZnSOD were open to this agent. Cu2+ was reduced to Cu1+, while manganese appears to be released from MnSOD active center. Untreated and O-2(-) treated FeSOD and MnSOD predominantly show 5 d-electron systems, i.e. Fe3+ and Mn2+. Our study provides new details on the mechanisms of (patho)physiological effects of HS-/H2S. (C) 2015 Elsevier Inc. All rights reserved.Ministry for Education, Science and Technological Development of The Republic of Serbia {[}173014, III41005

Ex vivo effects of ibogaine on the activity of antioxidative enzymes in human erythrocytes

Ethnopharmacological relevance: Ibogaine is a naturally occurring alkaloid with psychotropic and metabotropic effects, derived from the bark of the root of the West African Tabernanthe iboga plant. The tribes of Kongo basin have been using iboga as a stimulant, for medicinal purposes, and in rite of passage ceremonies, for centuries. Besides, it has been found that this drug has anti-addictive effects. Aim of the study: Previous studies have demonstrated that ibogaine changed the quantity of ATP and energy related enzymes as well as the activity of antioxidant enzymes in cells thus altering redox equilibrium in a time manner. In this work, the mechanism of its action was further studied by measuring the effects of ibogaine in human erythrocytes in vitro on ATP liberation, membrane fluidity and antioxidant enzymes activity. Materials and methods: Heparinized human blood samples were incubated with ibogaine (10 and 20 mu M) at 37 degrees C for 1 h. Blood plasma was separated by centrifugation and the levels of ATP and uric acid were measured 10 mm after the addition of ibogaine using standard kits. The activity of copper zinc superoxide dismutase (SOD1), catalase (CAT), glutathione peroxidase (GSH-Px) and glutathione reductase (GR) were measured in erythrocytes after incubation period. The stability of SOD1 activity was further tested through in vitro incubation with H2O2 and scanning of its electrophoretic profiles. Membrane fluidity was determined using an electron paramagnetic resonance spin-labelling method. Results: Results showed that ibogaine treatment of erythrocytes in vitro increased ATP concentration in the blood plasma without changes in neither erythrocytes membrane fluidity nor uric acid concentration. lbogaine also increased SOD1 activity in erythrocytes at both doses applied here. Treatment with 20 mu M also elevated GR activity after in vitro incubation at 37 degrees C. Electrophoretic profiles revealed that incubation with ibogaine mitigates H2O2 mediated suppression of SOD1 activity. Conclusion: Some of the effects of ibogaine seem to be mediated through its influence on energy metabolism, redox active processes and the effects of discrete fluctuations of individual reactive oxygen species on different levels of enzyme activities. Overall, ibogaine acts as a pro-antioxidant by increasing activity of antioxidative enzymes and as an adaptagene in oxidative distress. (C) 2015 Published by Elsevier Ireland Ltd.Ministry of Science and Technological Development of the Republic of Serbia, ``Molecular mechanisms of redox signaling in homeostasis: adaptation and pathology{''}, University of Belgrade {[}173014