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The health promotion school program was designed to promote the wellbeing of school students. This concept was introduced during the 1980s by the World Health Organization (WHO). In Sri Lanka; it was initiated and implemented in 2008 targeting all government schools. The aim of the study was to assess the existing school health promotion program. The cross-sectional study was implemented in May 2018 with all secondary schools in a selected education zone in Sri Lanka which represent three types of schools, 1AB, 1C and type 2. The study participants were students and teachers. The newly developed tool (Health Promoting School Assessment Tool) was used to assess the existing school health promotion program under six main criteria. The nominal group technique was followed to fill the assessment tool designed in the study where a team of teachers and a team of students separately took part in the assessment. The findings of the study show that the existing health promotion school program is partially unsuccessful in the selected educational zone. The existing situation of the school health promotion program, according to the main six criteria of the Health Promotion School Assessment Tool, was not at a satisfactory level of the implementation (38.2%). Only three schools (N=23) scored more than 50% while other schools (n=20, N=23) were scored less than 50%. According to the assessment, for each group of an individual school, there was a difference between teachers’ assessment and students’ assessment of the overall health promotion program. It is important to conduct continuous monitoring and have an evaluation plan for the school health promotion program to acquire effective changes in school settings.

Dysregulated excitability within the spinal dorsal horn is a critical mediator of chronic pain. Dedek et al. report that downregulation of tyrosine phosphatase STEP61 links disinhibition to NMDAR potentiation in human and rodent spinal pain processing, and develop an ex vivo human preclinical model to help bridge the translational divide., Dysregulated excitability within the spinal dorsal horn is a critical mediator of chronic pain. In the rodent nerve injury model of neuropathic pain, BDNF-mediated loss of inhibition (disinhibition) gates the potentiation of excitatory GluN2B N-methyl-d-aspartate receptor (NMDAR) responses at lamina I dorsal horn synapses. However, the centrality of this mechanism across pain states and species, as well as the molecular linker involved, remain unknown. Here, we show that KCC2-dependent disinhibition is coupled to increased GluN2B-mediated synaptic NMDAR responses in a rodent model of inflammatory pain, with an associated downregulation of the tyrosine phosphatase STEP61. The decreased activity of STEP61 is both necessary and sufficient to prime subsequent phosphorylation and potentiation of GluN2B NMDAR by BDNF at lamina I synapses. Blocking disinhibition reversed the downregulation of STEP61 as well as inflammation-mediated behavioural hypersensitivity. For the first time, we characterize GluN2B-mediated NMDAR responses at human lamina I synapses and show that a human ex vivo BDNF model of pathological pain processing downregulates KCC2 and STEP61 and upregulates phosphorylated GluN2B at dorsal horn synapses. Our results demonstrate that STEP61 is the molecular brake that is lost following KCC2-dependent disinhibition and that the decrease in STEP61 activity drives the potentiation of excitatory GluN2B NMDAR responses in rodent and human models of pathological pain. The ex vivo human BDNF model may thus form a translational bridge between rodents and humans for identification and validation of novel molecular pain targets.

The prevalence and severity of many chronic pain syndromes differ across sex, and recent studies have identified differences in immune signalling within spinal nociceptive circuits as a potential mediator. Although it has been proposed that sex-specific pain mechanisms converge once they reach neurons within the superficial dorsal horn, direct investigations using rodent and human preclinical pain models have been lacking. Here, we discovered that in the Freund’s adjuvant in vivo model of inflammatory pain, where both male and female rats display tactile allodynia, a pathological coupling between KCC2-dependent disinhibition and N-methyl-D-aspartate receptor (NMDAR) potentiation within superficial dorsal horn neurons was observed in male but not female rats. Unlike males, the neuroimmune mediator brain-derived neurotrophic factor (BDNF) failed to downregulate inhibitory signalling elements (KCC2 and STEP61) and upregulate excitatory elements (pFyn, GluN2B and pGluN2B) in female rats, resulting in no effect of ex vivo brain-derived neurotrophic factor on synaptic NMDAR responses in female lamina I neurons. Importantly, this sex difference in spinal pain processing was conserved from rodents to humans. As in rodents, ex vivo spinal treatment with BDNF downregulated markers of disinhibition and upregulated markers of facilitated excitation in superficial dorsal horn neurons from male but not female human organ donors. Ovariectomy in female rats recapitulated the male pathological pain neuronal phenotype, with BDNF driving a coupling between disinhibition and NMDAR potentiation in adult lamina I neurons following the prepubescent elimination of sex hormones in females. This discovery of sexual dimorphism in a central neuronal mechanism of chronic pain across species provides a foundational step towards a better understanding and treatment for pain in both sexes.

The prevalence and severity of many chronic pain syndromes differ across sex, and recent studies have identified differences in immune signalling within spinal nociceptive circuits as a potential mediator. Although it has been proposed that sex-specific pain mechanisms converge once they reach neurons within the superficial dorsal horn (SDH), direct investigations using rodent and human preclinical pain models have been lacking. Here, we discovered that in the Freund’s Adjuvant in vivo model of inflammatory pain, where both male and female rats display tactile allodynia, a pathological coupling between KCC2-dependent disinhibition and NMDA receptor potentiation within SDH neurons was observed in male but not female rats. Unlike males, the neuroimmune mediator, BDNF, failed to downregulate inhibitory signalling elements (KCC2 and STEP61) and upregulate excitatory elements (pFyn, GluN2B, and pGluN2B) in female rats, resulting in no effect of ex vivo BDNF on synaptic NMDA receptor responses in female lamina I neurons. Importantly, this sex difference in spinal pain processing was conserved from rodents to humans. As in rodents, ex vivo spinal treatment with BDNF downregulated markers of disinhibition and upregulated markers of facilitated excitation in SDH neurons from male but not female human organ donors. Ovariectomy in female rats recapitulated the male pathological pain neuronal phenotype, with BDNF driving a coupling between disinhibition and NMDA receptor potentiation in adult lamina I neurons following the prepubescent elimination of sex hormones in females. This discovery of sexual dimorphism in a central neuronal mechanism of chronic pain across species provides a foundational step towards a better understanding and treatment for pain in both sexes.

Iron is the most prevalent metal in biology. Its chemical and redox versatility allows it to direct activity of many Fe binding proteins. While iron's biological applications are diverse, challenges inherent in having Fe(II) present at high abundance means cells must ensure delivery to the correct recipient, while also ensuring its chemistry is regulated. Having a detailed understanding of the biophysical characteristics of a protein's iron binding characteristics allows us to understand general cellular metal homeostasis events. Unfortunately, most spectroscopic techniques available to measure metal binding affinity require protein be in a homogeneous state. Homogeneity creates an artificial environment when measuring metal binding since within cells numerous additional metal binding biomolecules compete with the target. Here we investigate commercially available Fe(II) chelators with spectral markers coupled to metal binding and release. Our goal was to determine their utility as competitors while measuring aspects of metal binding by apoproteins during a metal binding competition assay. Adding chelators during apoprotein metal binding mimics heterogeneous metal binding environments present in vivo, and provides a more realistic metal binding affinity measurement. Ferrous chelators explored within this report include: Rhod-5N, Magfura-2, Fura-4F, Fura-2, and TPA (Tris-(2-byridyl-methyl)amine; each forms a 1:1 complex with Fe(II) and combined cover a binding range of 5 orders of magnitude (micromolar to nanomolar Kd). These chelators were used to calibrate binding affinities for yeast and fly frataxin (Yfh1 and Dfh, respectively), involved in mitochondrial Fe S cluster bioassembly.

FeS-clusters are utilized by numerous proteins within several biological pathways that are essential for life. In eukaryotes, the primary FeS-cluster production pathway is the mitochondrial iron-sulfur cluster (ISC) pathway. In Saccharomyces cerevisiae, de novo FeS-cluster formation is accomplished through coordinated assembly with the substrates iron and sulfur by the scaffold assembly protein "Isu1". Sulfur for cluster assembly is provided by cysteine desulfurase "Nfs1", a protein that works in union with its accessory protein "Isd11". Frataxin "Yfh1" helps direct cluster assembly by serving as a modulator of Nfs1 activity, by assisting in the delivery of sulfur and Fe(ii) to Isu1, or more likely through a combination of these and other possible roles. In vitro studies on the yeast ISC machinery have been limited, however, due to the inherent instability of recombinant Isu1. Isu1 is a molecule prone to degradation and aggregation. To circumvent Isu1 instability, we have replaced yeast Isu1 with the fly ortholog to stabilize our in vitro ISC assembly system and assist us in elucidating molecular details of the yeast ISC pathway. Our laboratory previously observed that recombinant frataxin from Drosophila melanogaster has remarkable stability compared to the yeast ortholog. Here we provide the first characterization of D. melanogaster Isu1 (fIscU) and demonstrate its ability to function within the yeast ISC machinery both in vivo and in vitro. Recombinant fIscU has physical properties similar to that of yeast Isu1. It functions as a stable dimer with similar Fe(ii) affinity and ability to form two 2Fe-2S clusters as the yeast dimer. The fIscU and yeast ISC proteins are compatible in vitro; addition of Yfh1 to Nfs1-Isd11 increases the rate of FeS-cluster formation on fIscU to a similar extent observed with Isu1. Finally, fIscU expressed in mitochondria of a yeast strain lacking Isu1 (and its paralog Isu2) is able to completely reverse the deletion phenotypes. These results demonstrate fIscU can functionally replace yeast Isu1 and it can serve as a powerful tool for exploring molecular details within the yeast ISC pathway.

Cadmium is a known carcinogen that has been implicated in prostate cancer, but how it affects prostate carcinogenesis in humans remains unclear. Evidence from basic science suggests that cadmium can bind to the androgen receptor causing endocrine disruption. The androgen receptor is required for normal prostate development and is the key driver of prostate cancer progression. In this study, we examined the association between cadmium content and androgen receptor protein expression in prostate cancer tissue of African American (N = 22) and European American (N = 30) men. Although neither overall tumor cadmium content (log transformed) nor androgen receptor protein expression level differed by race, we observed a race-cadmium interaction with regard to androgen receptor expression ( P = 0.003) even after accounting for age at prostatectomy, smoking history, and Gleason score. African American men had a significant positive correlation between tumor tissue cadmium content and androgen receptor expression (Pearson correlation = 0.52, P = 0.013), while European Americans showed a non-significant negative correlation between the two (Pearson correlation = −0.19, P = 0.31). These results were unchanged after further accounting for tissue zinc content or dietary zinc or selenium intake. African American cases with high-cadmium content (>median) in tumor tissue had more than double the androgen receptor expression (0.021 vs. 0.008, P = 0.014) of African American men with low-cadmium level. No difference in androgen receptor expression was observed in European Americans by cadmium level (high 0.015 vs. low 0.011, P = 0.30). Larger studies are needed to confirm these results and if upheld, determine the biologic mechanism by which cadmium increases androgen receptor protein expression in a race-dependent manner. Our results suggest that cadmium may play a role in race disparities observed in prostate cancer.

Using high-precision Penning trap mass spectrometry at the Low Energy Beam and Ion Trap facility at the National Superconducting Cyclotron Laboratory we have measured the $Q$ values of the fourth-order forbidden $\ensuremath{\beta}$ decay and electron capture of $^{50}\mathrm{V}$ and the double electron capture $Q$ value of $^{50}\mathrm{Cr}$ with the results ${Q}_{\ensuremath{\beta}}(^{50}\mathrm{V})=1038.1(1)$ keV, ${Q}_{\mathrm{EC}}(^{50}\mathrm{V})=2208.7(1)$ keV, and ${Q}_{2\mathrm{EC}}(^{50}\mathrm{Cr})=1170.5(1)$ keV. In addition, we have measured the atomic masses of $^{46,47,49,50}\mathrm{Ti},^{50,51}\mathrm{V}$, and $^{50,52--54}\mathrm{Cr}$, reducing uncertainties by factors of up to three compared with the most recent atomic mass evaluation $(Ame2016)$ [Chin. Phys. C 41, 030003 (2017)]. Our results are in good agreement with $Ame2016$ for $^{46,47,49,50}\mathrm{Ti}$ and $^{50,54}\mathrm{Cr}$ and show deviations of up to $\ensuremath{\sim}1\phantom{\rule{4pt}{0ex}}\mathrm{keV}\phantom{\rule{4pt}{0ex}}(2.5\ensuremath{\sigma})$ for $^{50,51}\mathrm{V}$ and $^{50,54}\mathrm{Cr}$.

Organoarsenicals such as the methylarsenical methylarsenate (MAs(V)) and aromatic arsenicals including roxarsone (4-hydroxy-3-nitro-benzenearsenate or Rox(V)) have been extensively used as an herbicide and growth enhancers in animal husbandry, respectively. They undergo environmental degradation to more toxic inorganic arsenite (As(III)) that contaminates crops and drinking water. We previously identified a bacterial gene (arsI) responsible for aerobic demethylation of methylarsenite (MAs(III)). The gene product, ArsI, is an Fe(II)-dependent extradiol dioxygenase that cleaves the carbon–arsenic (C–As) bond in MAs(III) and in trivalent aromatic arsenicals. The objective of this study was to elucidate the ArsI mechanism. Using isothermal titration calorimetry, we determined the dissociation constants and ligand-to-protein stoichiometry of ArsI for Fe(II), MAs(III), and aromatic phenylarsenite. Using a combination of methods including chemical modification, site-directed mutagenesis, and fluorescent spectroscopy, we demonstrated that amino acid residues predicted to participate in Fe(II)-binding (His5–His62–Glu115) and substrate binding (Cys96–Cys97) are involved in catalysis. Finally, the products of Rox(III) degradation were identified as As(III) and 2-nitrohydroquinone, demonstrating that ArsI is a dioxygenase that incorporates one oxygen atom from dioxygen into the carbon and the other to the arsenic to catalyze cleavage of the C–As bond. These results augment our understanding of the mechanism of this novel C–As lyase.

Parkinson’s disease (PD) is a progressive neurodegenerative disorder, and development of disease-modifying treatment is still an unmet medical need. Considering the implication of free iron(II) in PD, we report here the design and characterization of a novel hybrid iron chelator, (−)-12 (D-607) as a multitarget-directed ligand against PD. Binding and functional assays at dopamine D2/D3 receptors indicate potent agonist activity of (−)-12. The molecule displayed an efficient preferential iron(II) chelation properties along with potent in vivo activity in a reserpinized PD animal model. The compound also rescued PC12 cells from toxicity induced by iron delivered intracellularly in a dose-dependent manner. However, Fe3+ selective dopamine agonist 1 and a well-known antiparkinsonian drug pramipexole produced little to no neuroprotection effect under the same experimental condition. These observations strongly suggest that (−)-12 should be a promising multifunctional lead molecule for a viable symptomatic and ...

A new variation of the drop-off method for fabricating field emission points by electrochemically etching tungsten rods in a NaOH solution is described. The results of studies in which the etching current and the molarity of the NaOH solution used in the etching process were varied are presented. The investigation of the geometry of the tips, by imaging them with a scanning electron microscope, and by operating them in field emission mode is also described. The field emission tips produced are intended to be used as an electron beam source for ion production via electron impact ionization of background gas or vapor in Penning trap mass spectrometry applications.

Studies have been conducted on the copper complexes formed with two sexadentate macrocyclic ligands containing four thioether sulfur donor atoms plus either two nitrogen or two oxygen donor atoms on opposing sides of the ring. The resulting two ligands, L, designated as [18]aneS4N2 and [18]aneS4O2, respectively, represent homologues of the previously studied Cu(II/I) system with a macrocycle having six sulfur donor atoms, [18]aneS6. Crystal structures of [CuII([18]aneS4O2)](ClO4)2 and [CuI([18]aneS4O2)]ClO4 have been determined in this work. Comparison of the structures of all three systems reveals that the oxidized complexes are six coordinate with two coordinate bonds undergoing rupture upon reduction. However, the geometric changes accompanying electron transfer appear to differ for the three systems. The stability constants and electrochemical properties of both of the heteromacrocyclic complexes have been determined in acetonitrile and the CuII/IL electron-transfer kinetics have been studied in the same solvent using six different counter reagents for each system. The electron self-exchange rate constants have then been calculated using the Marcus cross relationship. The results are compared to other CuII/IL systems in terms of the effect of ligand geometric changes upon the overall kinetic behavior.

The Staphylococcus aureus plasmid pI258 cadCA operon encodes a P-type ATPase, CadA, that confers resistance to the heavy metals Cd(II), Zn(II), and Pb(II). Expression of this heavy-metal efflux pump is regulated by CadC, a homodimeric repressor that dissociates from the cad operator/promoter upon binding of Cd(II), Pb(II), or Zn(II). CadC is a member of the ArsR/SmtB family of metalloregulatory proteins. Here we report the X-ray crystal structure of CadC at 1.9 Å resolution. The dimensions of the protein dimer are approximately 30 Å by 40 Å by 70 Å. Each monomer contains six α-helices and a three-stranded β-sheet. Helices 4 and 5 form a classic helix-turn-helix motif that is the putative DNA binding region. The α1 helix of one monomer crosses the dimer to approach the α4 helix of the other monomer, consistent with the previous proposal that these two regulatory metal binding sites for the inducer cadmium or lead are each formed by Cys-7 and Cys-11 from the N terminus of one monomer and Cys-58 and Cys-60 of the other monomer. Two nonregulatory metal binding sites containing zinc are formed between the two antiparallel α6 helices at the dimerization interface. This is the first reported three-dimensional structure of a member of the ArsR/SmtB family with regulatory metal binding sites at the DNA binding domain and the first structure of a transcription repressor that responds to the heavy metals Cd(II) and Pb(II).

At Central Michigan University we are developing a high-precision Penning trap mass spectrometer (CHIP-TRAP)that will focus on measurements with long-lived radioactive isotopes. CHIP-TRAP will consist of a pair of hyperbolic precision-measurement Penning traps, and a cylindrical capture/filter trap in a 12 T magnetic field. Ions will be produced by external ion sources, including a laser ablation source, and transported to the capture trap at low energies enabling ions of a given m=q ratio to be selected via their time-of-flight. In the capture trap, contaminant ions will be removed with a mass-selective rf dipole excitation and the ion of interest will be transported to the measurement traps. A phase-sensitive image charge detection technique will be used for simultaneous cyclotron frequency measurements on single ions in the two precision traps, resulting in a reduction in statistical uncertainty due to magnetic field fluctuations., Comment: 5 pages, submitted to NIMB (EMIS 2015 Conference Proceedings)

The electron-transfer kinetics of copper(II/I) complexes formed with the macrocyclic terdentate ligand 1,4,7-trithiacyclononane ([9]aneS3 = TTCN = L) have been investigated under a variety of conditions. The relevant equilibrium constants, complex formation and dissociation rate constants, and redox potentials in both water and acetonitrile have also been determined. The predominant oxidized species in both solvents is CuIIL2, although the 1 ∶ 1 complex, CuIIL(H2O)3, can become dominant in water at high Cu(II) concentrations. The predominant reduced species is the 1 ∶ 1 complex, CuIL (i.e., CuIL(H2O) or CuIL(CH3CN)), as confirmed by electrospray mass spectrometry, pulsed square-wave voltammetry, cyclic voltammetry and the ligand dependence of the oxidation kinetics. Electron transfer occurs almost exclusively through the bis redox couple, CuII/IL2, even for solutions containing predominantly CuIIL(H2O)3. In the latter case, reduction involves a three-step sequence in which (i) CuIIL(H2O)3 reacts with L to produce CuIIL2, (ii) electron transfer occurs and (iii) L dissociates again to yield CuIL(H2O). The sluggishness of direct electron transfer in the 1 ∶ 1 complex is attributed to the unfavorable energetics of forming or dissociating strong copper–solvent bonds combined with the accompanying re-structuring of the surrounding solvent.

Most of a broad series of buffers developed by Good (often called "Good's" or "Good" buffers) have been shown to cause metal ion interference as a result of complexation. A series of tertiary amines, devoid of hydroxy groups or other weak donors on the α, β, or γ carbons, have been developed as "Better" pH buffers which, as a result of steric hindrance, are incapable of forming even weak complexes with metal ions. As a result, they avert interferences of the type often encountered in metal ion studies which require buffer use. The compounds studied are alkyl and alkylsulfonate derivatives of morpholine (3), piperazine (3), ethylenediamine (3), and methylenediamine (1). With the exception of the morpholine derivatives, these compounds have two protonatable sites and, therefore, can be used to buffer two separate pH regions. A series of 10 buffer compounds span the entire range of pH 3-11. The acid dissociation constants for these compounds have now been determined in aqueous solution at 15, 25, 35 and 45 °C, μ = 0.10 M. From these data, apparent enthalpy and entropy values have been calculated to permit application at other temperatures as well. These buffers are recommended for use in all situations in which metal ions are present. All of the reported compounds are now commercially available.