The Voice of Low-Income Adolescent Mothers on Infant Feeding

Adolescent mothers\u27 feeding practices impact infant weight gain. Infant obesity, especially in low-income families, is rapidly increasing. The aim of the exploratory study reported here was to identify factors affecting low-income African American and non-Hispanic White adolescent mothers\u27 infant feeding practices and useful learning modalities. Two focus groups were conducted by a trained facilitator using a semi-structured topic guide. Three themes emerged: (1) feeding decisions related to introduction of solid foods; (2) feeding information/advice provided by others; and (3) useful learning strategies. These themes can be used by Extension professionals in designing nutrition education programs for adolescent mothers

Some Physical Properties of Concentrated Aqueous Salt Solutions

The densities and refractive indices were determined at 25° for solutions of the halides of some of the alkali metals, over a concentration range from 0.1 molal to almost saturation. The partial molal volumes were calculated by differentiating the equations of the volume-molality curves. From the refractive index the specific refractivity of the solution and of the solute were calculated. The specific refractivity of the solute was found to be constant throughout the concentrations studied. Using an equation derived by Hückel, involving the refractive index, the dielectric constants of the solutions were calculated

Model Hamiltonian for Topological Insulators

In this paper we give the full microscopic derivation of the model Hamiltonian for the three dimensional topological insulators in the $Bi_2Se_3$ family of materials ($Bi_2Se_3$, $Bi_2Te_3$ and $Sb_2Te_3$). We first give a physical picture to understand the electronic structure by analyzing atomic orbitals and applying symmetry principles. Subsequently, we give the full microscopic derivation of the model Hamiltonian introduced by Zhang {\it et al} [\onlinecite{zhang2009}] based both on symmetry principles and the ${\bf k}\cdot{\bf p}$ perturbation theory. Two different types of $k^3$ terms, which break the in-plane full rotation symmetry down to three fold rotation symmetry, are taken into account. Effective Hamiltonian is derived for the topological surface states. Both the bulk and the surface models are investigated in the presence of an external magnetic field, and the associated Landau level structure is presented. For more quantitative fitting to the first principle calculations, we also present a new model Hamiltonian including eight energy bands.Comment: 18 pages, 9 figures, 5 table

Analysis of leukocyte membrane protein interactions using protein microarrays

BACKGROUND: Protein microarrays represent an emerging class of proteomic tools to investigate multiple protein-protein interactions in parallel. A sufficient proportion of immobilized proteins must maintain an active conformation and an orientation that allows for the sensitive and specific detection of antibody and ligand binding. In order to establish protein array technology for the characterization of the weak interactions between leukocyte membrane proteins, we selected the human leukocyte membrane protein CD200 (OX2) and its cell surface receptor (hCD200R) as a model system. As antibody-antigen reactions are generally of higher affinity than receptor-ligand binding, we first analyzed the reactivity of monoclonal antibodies (mAb) to normal and mutant forms of immobilized CD200R. RESULTS: Fluorescently labelled mAb DX147, DX136 and OX108 were specifically reactive with immobilized recombinant hCD200R extracellular region, over a range of 0.1–40 μg ml(-1 )corresponding to a limit of sensitivity of 0.01–0.05 femtomol per spot. Orientating hCD200R using capture antibodies, showed that DX147 reacts with an epitope spatially distinct from the more closely related DX136 and OX108 epitopes. A panel of soluble recombinant proteins with mutations in hCD200R domain 1 produced by transiently transfected cells, was arrayed directly without purification and screened for binding to the three mAb. Several showed decreased binding to the blocking mAb DX136 and OX108, suggesting close proximity of these epitopes to the CD200 binding site. Binding of hCD200 to directly immobilized rat, mouse, and hCD200R was achieved with multimeric ligands, in the form of biotinylated-hCD200 coupled to FITC-labelled avidin coated beads. CONCLUSION: We have achieved sensitive, specific and reproducible detection of immobilized CD200R with different antibodies and mapped antigenic epitopes for two mAb in the vicinity of the ligand binding site using protein microarrays. We also detected CD200 binding to its receptor, a low affinity interaction, using beads presenting multivalent ligands. Our results demonstrate the quantitative aspects of protein arrays and their potential use in detecting simultaneously multiple protein-protein interactions and in particular the weak interactions found between leukocyte membrane proteins

State Anxiety Is Associated with Cardiovascular Reactivity in Young, Healthy African Americans

Although several studies have shown that enhanced cardiovascular reactivity can predict hypertension development in African Americans, these findings have not been consistent among all studies examining reactivity and hypertension susceptibility. This inconsistency may be explained by the influence of anxiety (state and trait) on the blood pressure response to stress. Therefore, this study sought to determine whether anxiety is associated with blood pressure response to cold pressor (CP) and anger recall (AR) stress tests in young healthy African Americans. Modeling using state and trait anxiety revealed that state anxiety predicts systolic (SBP) and diastolic blood pressure DBP response to CP and AR (P ≤ 0.02). Interestingly, state anxiety predicted heart rate changes only to CP (P < 0.01; P = 0.3 for AR). Although trait anxiety was associated with SBP response to AR and not CP, it was not a significant predictor of reactivity in our models. We conclude that anxiety levels may contribute to the variable blood pressure response to acute stressors and, therefore, should be assessed when performing cardiovascular reactivity measures

Environmental monitoring at St George’s Bay (Malta) in connection with beach replenishment works

This study was financed by the Malta Tourism Authority (MTA) through contract dated 14th April 2004 and tender MTA/104/2004 dated 26th November 2004, both awarded to Ecoserv.Adverse impacts of coastal beach replenishment projects on the marine environment are well documented. As a result, coastal managers have been seeking ways and techniques with which to implement beach replenishment projects without causing adverse changes to marine ecosystems. In May 2004, the Malta Tourism Authority undertook beach replenishment at St George’s Bay (St Julians, Malta) in which coarse sediment of terrestrial origin, having a mean grain size of 2 mm, was deposited at the head of the bay to create an artificial beach. An extensive 2-year (January 2004 to December 2005) environmental monitoring programme was commissioned by the MTA to monitor the potential impacts of the replenishment works on the marine environment. The programme included surveys of physico-chemical attributes (beach and seabed profile surveys, granulometric analysis and microscopic examination of sublittoral sediments, and water quality studies), and use of seagrass as a bioindicator of environmental quality. For most of the attributes surveyed, data was collected from stations located within the putatively ‘impacted’ inlet, and from control stations before initiation of the works and following the beach replenishment works. Data for mean sediment grain size, water quality attributes (salinity, dissolved oxygen, total suspended solids and nutrients) and seagrass morphometric parameters (shoot density, length and biomass of adult leaves, and shoot epiphyte biomass) were analysed using analysis of variance (ANOVA). Overall, the results of the various monitoring components indicated that (i) no major transport of sediment from the beach to the sublittoral had occurred, and (ii) the beach replenishment works did not result in any adverse impacts on the marine environment. Good project planning and management, the relatively sheltered location of the replenished beach, together with appropriate choice of grain size of the sand used for replenishment appear to have contributed to the success of the project.peer-reviewe

Creating New β-Globin-Expressing Lentiviral Vectors by High-Resolution Mapping of Locus Control Region Enhancer Sequences.

Hematopoietic stem cell gene therapy is a promising approach for treating disorders of the hematopoietic system. Identifying combinations of cis-regulatory elements that do not impede packaging or transduction efficiency when included in lentiviral vectors has proven challenging. In this study, we deploy LV-MPRA (lentiviral vector-based, massively parallel reporter assay), an approach that simultaneously analyzes thousands of synthetic DNA fragments in parallel to identify sequence-intrinsic and lineage-specific enhancer function at near-base-pair resolution. We demonstrate the power of LV-MPRA in elucidating the boundaries of previously unknown intrinsic enhancer sequences of the human β-globin locus control region. Our approach facilitated the rapid assembly of novel therapeutic βAS3-globin lentiviral vectors harboring strong lineage-specific recombinant control elements capable of correcting a mouse model of sickle cell disease. LV-MPRA can be used to map any genomic locus for enhancer activity and facilitates the rapid development of therapeutic vectors for treating disorders of the hematopoietic system or other specific tissues and cell types

Regulatory T cell profiles in patients with N-methyl-ᴅ-aspartate receptor-antibody encephalitis

Purpose Purpose Regulatory T cells (Tregs) have been implicated in the pathogenesis of several autoimmune disorders and used in adoptive cell transfer therapies. Neither have been explored in patients with autoimmune encephalitis where treated patient outcomes remain suboptimal with frequent relapses. Here, to identify new treatment strategies for autoimmune encephalitis, we sought to evaluate the proportion of circulating Tregs and Treg subpopulations in peripheral blood of patients with N-methyl-ᴅ-aspartate receptor-antibody encephalitis (NMDAR-Ab-E) and compared this with healthy controls. Methods We compared the phenotype of peripheral blood Tregs in four adult NMDAR-Ab-E patients and four age- and sex-matched healthy controls using an 11-color flow cytometry assay panel for characterization of Tregs (CD4+ CD25+ FoxP3+) cells into naïve (chemokine receptor [CCR] 7+ CD45RA+), central memory (CCR7+ CD45RA–), and effector memory (CCR7– CD45RA–) cells. We also examined and compared the expression of the CCR6 by circulating Tregs and the respective Treg subpopulations between the study groups. Results The proportion of circulating Tregs was similar between patients with NMDAR-Ab-E and healthy controls but the proportion of naïve Tregs was lower in NMDAR-Ab-E patients (p = 0.0026). Additionally, the frequency of circulating effector memory Tregs was higher, and the proportion of circulating effector memory Tregs expressing CCR6 was lower, in NMDAR-Ab-E patients compared with healthy controls (p = 0.0026). Conclusion Altered Treg homeostasis may be a feature of patients with NMDAR-Ab-E. Future studies with larger samples are warranted to validate these findings

Artificial Reefs Project : final report of scientific studies (2004–2006)

A study was undertaken to assess the environmental impact of four artificial reef units on the soft sediment marine benthic assemblages and fish fauna in their vicinity, and to evaluate the reefs’ potential as a habitat. Another aim of the study was to assess whether the two different materials used to construct the reefs – native Globigerina limestone and a concrete mixture that incorporated Globigerina debris – had different effects on the benthic biota and fish fauna. To assess the impact of the artificial reefs on the soft sediment benthic fauna, five replicate sediment cores (diameter: 10 cm) were collected from each of five stations positioned at incremental distances (1, 2, 5, 10, 20 and 50 m) along each of two transects located on opposite sides (west and east) of each of two artificial reef locations. Five replicate samples were also collected from each of two control sites that had similar seabed characteristics as the reef sites. Additionally, three sediment cores were collected from the reef and reference stations to measure the mean grain-size and percentage organic carbon content of the sediments. Samples for benthic faunal analysis and physico-chemical attributes were collected from the designated reef sites during winter 2003/2004 before deployment of the artificial reefs, and during winter/spring 2005 following deployment of the reefs.peer-reviewe