Pedestrian-oriented zoning moderates the relationship between racialized economic segregation and active travel to work, United States.

Objective: Pedestrian-oriented zoning, including zoning code reforms (ZCR), may be especially beneficial to racially and economically segregated communities, which may lack built environment features that support physical activity. This study examined associations between racialized economic segregation, measured by quintiles of the Index of Concentration at the Extremes, and public transit (PTW) and active travel (ATW) to work, and whether associations were moderated by pedestrian-oriented zoning provisions and ZCR, respectively.

Methods: Zoning codes effective as of 2010 representing 3914 US municipalities (45.

Sexual risk behavior among youth: modeling the influence of prosocial activities and socioeconomic factors.

Sexual activity among high-school-aged youths has steadily increased since the 1970s, emerging as a significant public health concern. Yet, patterns of youth sexual risk behavior are shaped by social class, race, and gender. Based on sociological theories of financial deprivation and collective socialization, we develop and test a model of the relationships among neighborhood poverty; family structure and social class position; parental involvement; prosocial activities; race; and gender as they predict youth sexual risk behavior.

Post-cranioplasty cerebrospinal fluid hydrodynamic changes: magnetic resonance imaging quantitative analysis.

The syndrome of the trephined has been described in many patients with cranial defects as an indication for cranioplasty. Cerebral blood flow changes, the effect of the atmospheric pressure on the brain, as well as cerebrospinal fluid hydrodynamic changes have been postulated as the possible reasons for this syndrome. Using dynamic phase-contrast magnetic resonance imaging we measured arterial, venous, and cerebrospinal fluid flow into and out of the skull, before and after cranioplasty in one patient whose bone flap was removed because of osteomyelitis.

Regulation of C1-inhibitor function by binding to type IV collagen and heparin.

Serpins inhibit proteinases by a branched pathway, in which an intermediate serpin-proteinase complex can either form a stable covalent serpin-proteinase complex or produce reactive center cleaved serpin in a substrate reaction. It was tested whether these competing reactions could be regulated for the serpin C1-inhibitor by ligand binding. C1-inhibitor bound to type IV collagen, laminin, and entactin.

Recombinant human pigment epithelium-derived factor (PEDF): characterization of PEDF overexpressed and secreted by eukaryotic cells.

Pigment epithelium-derived factor (PEDF) is a serpin found in the interphotoreceptor matrix of the eye, which, although not a proteinase inhibitor, possesses a number of important biological properties, including promotion of neurite outgrowth and differential expression in quiescent versus senescent states of certain cell types. The low amounts present in the eye, together with the impracticality of using the eye as a source for isolation of the human protein, make it important to establish a system for overexpression of the recombinant protein for biochemical and biological studies. We describe here the expression and secretion of full-length glycosylated human recombinant PEDF at high levels (> 20 micrograms/ mL) into the growth medium of baby hamster kidney cells and characterization of the purified rPEDF by circular dichroism and fluorescence spectroscopies and neurite outgrowth assay.

Resistance to ultraviolet light in Pseudomonas syringae: sequence and functional analysis of the plasmid-encoded rulAB genes.

The indigenous plasmids, pPSR1 and pPSR5, were each shown to confer resistance to ultraviolet light (UV) in Pseudomonas syringae (Ps) pv. syringae FF5. The UV-resistance (UVR) determinant was subcloned from a cosmid library of pPSR1, and sequence analysis revealed the presence of two ORFs, designated rulAB which are homologous to the Escherichia coli umuDC mutagenic DNA repair systems and other plasmid-encoded UVR operons.

The expanded racial and ethnic codes in the Medicare data files: their completeness of coverage and accuracy.

Objectives: This paper evaluates the new race/ethnicity codes for Asian Americans, Hispanics, and Native Americans that have recently been added to the Medicare enrollment database.

Methods: The race/ethnicity code revisions made by the Health Care Financing Administration are described and evaluated by (1) comparing the numbers of persons identified as Asian Americans, Hispanics, and Native Americans with corresponding population census projections and (2) determining whether Medicare enrollees born in Asian and Hispanic countries are assigned Asian and Hispanic codes.

Results: Among persons 65 years of age and older, approximately 24% of Hispanics, 17% of Native Americans, and 56% of Asian Americans are identifiable by the new codes.

Dissemination of the strA-strB streptomycin-resistance genes among commensal and pathogenic bacteria from humans, animals, and plants.

Gene transfer within bacterial communities has been recognized as a major contributor in the recent evolution of antibiotic resistance on a global scale. The linked strA-strB genes, which encode streptomycin-inactivating enzymes, are distributed worldwide and confer streptomycin resistance in at least 17 genera of gram-negative bacteria. Nucleotide sequence analyses suggest that strA-strB have been recently disseminated.

Delayed recognition memory span in HIV-1 infection.

We administered a spatial version of the Delayed Recognition Span Test (DRST), a working memory task performed abnormally by patients with basal ganglia disease, to a group of 96 HIV-seropositive and 83 seronegative subjects with a high prevalence of substance abuse. For comparison purposes, we also administered the Symbol-Digit Modalities Test (SDMT) and the Trail Making Test (TMT), measures which detect HIV-related mental slowing efficiently in gay men but are nonspecifically impaired in subjects with a history of substance abuse. As predicted, scores on the TMT and the SDMT did not discriminate the groups, but HIV-seropositive subjects had significantly shorter spatial spans (p < .

Thiol ester cleavage-dependent conformational change in human alpha 2-macroglobulin. Influence of attacking nucleophile and of Cys949 modification.

Cleavage of the thiol ester that exists between the side chains of Cys949 and Gln952 in human alpha 2-macroglobulin (alpha 2M) destabilizes the native conformation and leads to a large-scale conformational change that results in exposure of the receptor binding domain and to changes in electrophoretic mobility and sedimentation coefficient. The basis of this destabilization of the alpha 2M native conformation following thiol ester cleavage is not understood. We have extended observations that chemical modifications of the newly-formed SH in thiol ester-cleaved alpha 2M can slow the rate of conformational change in an attempt to determine the factors that influence the kinetic stability of the native conformation.

The unique amino-terminal peptide of cardiac troponin I regulates myofibrillar activity only when it is phosphorylated.

Protein kinase A (PKA) dependent phosphorylation of C-protein and cardiac troponin I (cTnI) is known to be associated with a reduced sensitivity to Ca2+. We have investigated the relative importance of each of these sites of phosphorylation in this effect by use of extraction/reconstitution experiments and mutagenesis of recombinant cTnI. Conditions developed for extraction of troponin (Tn) complex also resulted in extraction of C-protein.

Bait region-thiol ester mapping in human alpha 2-macroglobulin.

The separations between aromatic residues in the bait region and nitroxide spin labels attached to the thiol ester-forming residues (Cys949 and Gln952) in human alpha 2-macroglobulin (alpha 2M) have been determined from paramagnetic broadening effects of the spin labels on bait region 1H NMR signals. We found that both the Cys949 and Gln952 residues are within 11-17 A of the aromatic residues in the bait region, with closer approach of some residues to the Gln952 spin label than to the spin label attached to Cys949. A model of the location of bait regions and thiol esters within an alpha 2M half-molecule is proposed that places the bait regions in the central region of alpha 2M at the interface between the subunits.

S-ovalbumin, an ovalbumin conformer with properties analogous to those of loop-inserted serpins.

Most serpins are inhibitors of serine proteinases and are thought to undergo a conformational change upon complex formation with proteinase that involves partial insertion of the reactive center loop into a beta-sheet of the inhibitor. Ovalbumin, although a serpin, is not an inhibitor of serine proteinases. It has been proposed that this deficiency arises from the presence of a charged residue, arginine, at a critical point (P14) in the reactive center region, which prevents loop insertion into the beta-sheet and thereby precludes inhibitory properties.

Successful methylphenidate treatment of apathy after subcortical infarcts.

A patient with prominent apathy secondary to multiple subcortical infarcts was treated successfully with methylphenidate. SPECT and reaction time testing showed selective improvement of frontal system function, consistent with a recent model of frontal-subcortical circuits and behavior.

Troponin C - troponin I interactions and molecular signalling in cardiac myofilaments.

This chapter describes a current perception of the molecular interactions regulating myofilament activity in heart cells. The focus is on the interaction between troponin-C (TnC), the Ca(2+)-receptor and troponin I (TnI), an inhibitory protein. It is this interaction that appears to form a molecular switch that turns on the thin filament.

Lysine-heparin interactions in antithrombin. Properties of K125M and K290M,K294M,K297M variants.

Lysine residues in two different regions of antithrombin have been proposed to be involved in heparin binding and heparin-mediated acceleration of proteinase inhibition. Lysine 125 has been implicated as an essential heparin binding residue from chemical modification studies [Peterson, C. B.

A highly specific benzimidazole pyridazinone reverses phosphate-induced changes in cardiac myofilament activation.

Both Ca2+ and the actin cross-bridge reaction itself can activate contraction in myofilaments. We are interested in identifying ligands which modify one or both mechanisms of contractile activation with high affinity and specificity. Results presented here suggest that the benzimidazole-substituted pyridazinone, UD-CG 212 Cl, potently modulates myofilament activation by the cross-bridge reaction.

Absence of calponin phosphorylation in contracting or resting arterial smooth muscle.

We have tested the hypothesis of Winder and Walsh [(1990) J. Biol. Chem.