Surface area and pore size characteristics of nanoporous gold subjected to thermal, mechanical, or surface modification studied using gas adsorption isotherms, cyclic voltammetry, thermogravimetric analysis, and scanning electron microscopy.

Nitrogen adsorption/desorption isotherms are used to investigate the Brunauer, Emmett, and Teller (BET) surface area and Barrett-Joyner-Halenda (BJH) pore size distribution of physically modified, thermally annealed, and octadecanethiol functionalized np-Au monoliths. We present the full adsorption-desorption isotherms for N(2) gas on np-Au, and observe type IV isotherms and type H1 hysteresis loops. The evolution of the np-Au under various thermal annealing treatments was examined using scanning electron microscopy (SEM).

Five nuclear loci resolve the polyploid history of switchgrass (Panicum virgatum L.) and relatives.

Polyploidy poses challenges for phylogenetic reconstruction because of the need to identify and distinguish between homoeologous loci. This can be addressed by use of low copy nuclear markers. Panicum s.

Simulation reveals two major docking pathways between the hexapeptide GDYMNM and the catalytic domain of the insulin receptor protein kinase.

Extending a previous mining-minima approach to identifying the docking pathways between the hexapeptide GDYMNM and the catalytic domain of the insulin receptor tyrosine kinase (IRK), we found two major docking pathways connecting the binding pocket and the surface of the protein. One pathway was more likely to lead to phosphate transfer from ATP to the peptide as the distance between the γ-phosphate of ATP and the hydroxyl oxygen of the target tyrosine approached one that could facilitate reaction. The movement of the peptide along the pathways was found to couple with residues in the activation loop of the protein.

Neuroimaging markers of human immunodeficiency virus infection in South Africa.

Previous studies have reported cognitive deficits among HIV-positive individuals infected with clade C virus. However, no study has examined whether individuals predominately infected with clade C virus exhibit brain atrophy relative to healthy controls. This study examined volumetric differences between 28 HIV+ individuals and 23 HIV- controls from South Africa.

The impact of perceived stress and perceived control on anxiety and mood disorders in noncardiac chest pain.

Chest pain without detectable heart disease, noncardiac chest pain (NCCP), is linked with anxiety and depression. Theory posits stress and perceived control may relate to NCCP. We hypothesized stress would have direct and mediated effects via perceived control on anxiety and mood disorders in NCCP.

Synthetic membrane active amphiphiles.

During the past several decades, various synthetic organic compounds that form pores in bilayer membranes have been prepared and studied. These membrane active amphiphiles have also proved to be useful in affecting the transport of molecules into or through the bilayer. This article discusses the evolution of these compounds and exemplifies recent applications such as enhancement of antimicrobial activity.

Comparative Study of the Binding of Concanavalin A to Self-Assembled Monolayers Containing a Thiolated α-Mannoside on Flat Gold and on Nanoporous Gold.

We have prepared SAMs containing 8-mercaptooctyl α-D-mannopyranoside, either as a single component or in mixed SAMs with n-octanethiol on flat gold surfaces and on nanoporous gold. Electrochemical impedance spectroscopy showed that the mixed SAMs on flat gold surfaces showed the highest Con A binding near 1:9 solution molar ratio of thiolatedα-mannoside to n-octanethiol whereas those on NPG showed the highest response at 1:19 solution molar ratio of thiolated α-mannoside to n-octanethiol. Atomic force microscopy was employed to image the monolayers, and also to image the bound Con A protein.

Biogeography and ecology: towards the integration of two disciplines.

Although ecology and biogeography had common origins in the natural history of the nineteenth century, they diverged substantially during the early twentieth century as ecology became increasingly hypothesis-driven and experimental. This mechanistic focus narrowed ecology's purview to local scales of time and space, and mostly excluded large-scale phenomena and historical explanations. In parallel, biogeography became more analytical with the acceptance of plate tectonics and the development of phylogenetic systematics, and began to pay more attention to ecological factors that influence large-scale distributions.

Characterization of protein immobilization on nanoporous gold using atomic force microscopy and scanning electron microscopy.

Nanoporous gold (NPG), made by dealloying low carat gold alloys, is a relatively new nanomaterial finding application in catalysis, sensing, and as a support for biomolecules. NPG has attracted considerable interest due to its open bicontinuous structure, high surface-to-volume ratio, tunable porosity, chemical stability and biocompatibility. NPG also has the attractive feature of being able to be modified by self-assembled monolayers.

Noncardiac chest pain in children and adolescents: a biopsychosocial conceptualization.

Pediatric NCCP may be characterized by recurrent pain accompanied by emotional distress and functional impairment. This paper reviews and critiques literature on pediatric noncardiac chest pain (NCCP) and introduces a theoretical conceptualization to guide future study of NCCP in children and adolescents. A developmentally informed biopsychosocial conceptualization of NCCP etiology is proposed based on a synthesis of empirical evidence and clinical observations of pediatric NCCP within the context of relevant findings from the broader pediatric pain and anxiety literature.

Influence of kinetics of drug binding on EGFR signaling: a comparative study of three EGFR signaling pathway models.

We used three models of the epidermal growth factor receptor (EGFR) signaling pathway mimicking three different cell lines to study the effects of kinetics of drug binding on influencing molecular signaling in the pathways. With no incubation of drugs before the external cue epidermal growth factor (EGF) was applied, we found that fast kinetics of binding to protein kinases was advantageous in suppressing the production of the Extracellular signal-regulated kinase (ERK) that triggers cell proliferation, with some exceptions. Incubation of a drug with a protein kinase target for an hour before a pathway was initiated with an external cue made kinetics less significant, so did high concentration of drugs.

Alexithymia and anxiety sensitivity in patients with non-cardiac chest pain.

The aim of this study was to examine independent and combined influences of alexithymia and anxiety sensitivity on chest pain and life interference in patients with non-cardiac chest pain (NCCP). Theories of NCCP posit a central role for emotion in the experience of chest pain, however, studies have not examined how alexithymia characterized by a difficulty identifying or verbalizing emotions, may influence this relationship. This study examined 231 patients (56% females, M age=50 years) with chest pain seeking cardiac evaluation, who showed no abnormalities during exercise tolerance testing.

Influence of education on subcortical hyperintensities and global cognitive status in vascular dementia.

Subcortical hyperintensities (SH) on neuroimaging are a prominent feature of vascular dementia (VaD) and SH severity correlates with cognitive impairment in this population. Previous studies demonstrated that SH burden accounts for a degree of the cognitive burden among VaD patients, although it remains unclear if individual factors such as cognitive reserve influence cognitive status in VaD. To address this issue, we examined 36 individuals diagnosed with probable VaD (age = 77.

Effects of entertainment (mis) education: exposure to entertainment television programs and organ donation intention.

This study investigates antecedents and outcomes of entertainment television consumption in organ donation with the Orientation₁-Stimulus-Orientation₂-Response (O₁-S-O₂ -R) model. It reveals that organ donation knowledge seems significantly related to recall of entertainment television programs and attitudes toward organ donation. Meanwhile, recall of entertainment television programs significantly predicts people's perception of medical mistrust, which in turn negatively predicts attitudes toward organ donation, while attitudes toward organ donation significantly predict behavioral intention in signing a donor card.

Assessment and treatment of psychological factors in pediatric chest pain.

Chest pain is regularly encountered in pediatric medical settings and may be associated with many organic diagnoses that vary widely in morbidity and mortality. Patients with chest pain with and without organic disease may also suffer from comorbid, exacerbating, or causal psychopathology. This article provides practical general guidelines for psychological diagnosis and alleviation of emotional and behavioral difficulties.

Enhancement of antimicrobial activity by synthetic ion channel synergy.

Hydraphile synthetic ion channels were found to enhance the cytotoxicity to E. coli and B. subtilis of erythromycin, kanamycin, rifampicin, and tetracycline when co-administered with the antibiotic at sublethal concentrations of channel.

Nanoporous gold for enzyme immobilization.

Nanoporous gold (NPG) is a material of emerging interest for immobilization of biomolecules and -especially enzymes. NPG materials provide a high gold surface area onto which biomolecules can either be directly physisorbed or covalently linked after first modifying the NPG with a self-assembled monolayer. The material can be used as a high surface area electrode and with immobilized enzymes can be used for amperometric detection schemes.

Attrition in a multicenter clinical trial for panic disorder.

This study examined attrition in a multisite clinical trial for panic disorder. Of 379 eligible patients, 19 refused treatment (5% Refusal Rate), 104 discontinued treatment prematurely (19% Dropout Rate) or were withdrawn by the investigators (8% Withdrawal Rate), and 256 completed the treatment (68% Completion Rate). Logistic regression was used to examine 5 domains theorized to be related to attrition (e.

Derivatives of salicylic acid as inhibitors of YopH in Yersinia pestis.

Yersinia pestis causes diseases ranging from gastrointestinal syndromes to bubonic plague and could be misused as a biological weapon. As its protein tyrosine phosphatase YopH has already been demonstrated as a potential drug target, we have developed two series of forty salicylic acid derivatives and found sixteen to have micromolar inhibitory activity. We designed these ligands to have two chemical moieties connected by a flexible hydrocarbon linker to target two pockets in the active site of the protein to achieve binding affinity and selectivity.

Anxiety and hypervigilance to cardiopulmonary sensations in non-cardiac chest pain patients with and without psychiatric disorders.

We investigated body vigilance, cardiac anxiety, and the mediating role of interoceptive fear on pain in patients with non-cardiac chest pain (NCCP; a syndrome of chest pain in the absence of identifiable organic etiology). Patients were more attentive to cardiac-congruent sensations than cardiac-incongruent sensations (e.g.

Self-assembled, cogged hexameric nanotubes formed from pyrogallol[4]arenes with a unique branched side chain.

A branched side chain pyrogallol[4]arene self-assembles into a previously-unreported cogged hydrogen-bonded nanotube structure in the solid state and self-assembles at the air-water interface on the Langmuir trough.

Docking flexible peptide to flexible protein by molecular dynamics using two implicit-solvent models: an evaluation in protein kinase and phosphatase systems.

Reliable prediction of protein-ligand docking pose requires proper account of induced fit effects. Treating both the ligand and the protein as flexible molecules is still challenging because many degrees of freedom are involved. Peptides are one type of ligand that are particularly difficult to study because of their extreme flexibility.

Beyond thermodynamics: drug binding kinetics could influence epidermal growth factor signaling.

We modeled the kinetics of drug binding to protein kinases in the EGF signaling pathway relevant to non-small-cell lung cancer and found that binding kinetics could influence therapeutic potential, that fast binding kinetics was advantageous for most targets with a couple of exceptions, that targeting some protein kinases could enhance rather than attenuate the pathway, and that IC(50) could be sensitive to the kinetic parameters of drug binding.

A computational study of the phosphorylation mechanism of the insulin receptor tyrosine kinase.

Although various groups have studied the phosphorylation mechanism of the insulin receptor tyrosine kinase (IRK), an unanimous picture has not yet emerged. In this work, we performed a computational study to gain further insights. We first built a structural model of the reactant complex with the guide of several crystal structures and previous computational studies of the cyclic AMP-dependent protein kinase.