Oxide thin films as bioactive coatings.

Growth and survival of biological cells (eukaryotes and prokaryotes) on artificial environments often depend on their interactions with the specific surface. Various organic materials can be coated on substrates to assist cells' adhesion and other subsequent cellular processes. However, these coatings are expensive, degrade over short time period, and may even interfere with the cells' signaling processes.

Identification of Biofilm Inhibitors by Screening Combinatorial Libraries of Metal Oxide Thin Films.

With the rise in nosocomial infections worldwide, research on materials with an intrinsic ability to inhibit biofilm formation has been generating a great deal of interest. In the present work, we describe how thin film material libraries generated by pulsed laser deposition can be used for simultaneously screening several novel metal oxide mixtures that inhibit biofilm formation in a common human pathogen, Salmonella enterica serovar Typhimurium. We discovered that in a material library constructed using two metal oxides, the net effect on biofilm formation can be modeled as an addition of the activities of the individual oxides weighted to their relative composition at that particular point on the library.

Fabrication of a biomimetic ZeinPDA nanofibrous scaffold impregnated with BMP-2 peptide conjugated TiO nanoparticle for bone tissue engineering.

A biomimetic Zein polydopamine based nanofiber scaffold was fabricated to deliver bone morphogenic protein-2 (BMP-2) peptide conjugated titanium dioxide nanoparticles in a sustained manner for investigating its osteogenic differentiation potential. To prolong its retention time at the target site, BMP-2 peptide has been conjugated to titanium dioxide nanoparticles owing to its high surface to volume ratio. The effect of biochemical cues from BMP-2 peptide and nanotopographical stimulation of electrospun Zein polydopamine nanofiber were examined for its enhanced osteogenic expression of human fetal osteoblast cells.

Background lead and mercury exposures: Psychological and behavioral problems in children.

Background: The potential harm from exposure to nonessential metals, particularly mercury (Hg) and lead (Pb), has been the focus of research for years. Initial interest focused on relatively high exposures; however, recent evidence suggests that even background exposures might have adverse consequences for child development. Identifying the extent of these consequences is now a priority.

Enhancing image contrast of carbon nanotubes on cellular background using helium ion microscope by varying helium ion fluence.

Carbon nanotubes (CNTs) have become an important nano entity for biomedical applications. Conventional methods of their imaging, often cannot be applied in biological samples due to an inadequate spatial resolution or poor contrast between the CNTs and the biological sample. Here we report a unique and effective detection method, which uses differences in conductivities of carbon nanotubes and HeLa cells.

Correlation of nanoscale behaviour of forces and macroscale surface wettability.

In this manuscript, we demonstrate a method based on atomic force microscopy which enables local probing of surface wettability. The maximum pull-off force, obtained from force spectroscopy shows a remarkable correlation with the macroscopically observed water contact angle, measured over a wide variety of surfaces starting from hydrophilic, all the way through to hydrophobic ones. This relationship, consequently, facilitates the establishment of a universal behaviour.

The horizontally-acquired response regulator SsrB drives a Salmonella lifestyle switch by relieving biofilm silencing.

A common strategy by which bacterial pathogens reside in humans is by shifting from a virulent lifestyle, (systemic infection), to a dormant carrier state. Two major serovars of Salmonella enterica, Typhi and Typhimurium, have evolved a two-component regulatory system to exist inside Salmonella-containing vacuoles in the macrophage, as well as to persist as asymptomatic biofilms in the gallbladder. Here we present evidence that SsrB, a transcriptional regulator encoded on the SPI-2 pathogenicity-island, determines the switch between these two lifestyles by controlling ancestral and horizontally-acquired genes.

In vitro controlled release of cisplatin from gold-carbon nanobottles via cleavable linkages.

Carbon nanotubes' (CNTs) hollow interior space has been explored for biomedical applications, such as drug repository against undesirable inactivation. To further devise CNTs as smart material for controlled release of cargo molecules, we propose the concept of "gold-carbon nanobottles". After encapsulating cis-diammineplatinum(II) dichloride (cisplatin, CDDP) in CNTs, we covalently attached gold nanoparticles (AuNPs) at the open-tips of CNTs via different cleavable linkages, namely hydrazine, ester, and disulfide-containing linkages.

Component-Specific Analysis of Plasma Protein Corona Formation on Gold Nanoparticles Using Multiplexed Surface Plasmon Resonance.

At the nano-bio interface, human plasma differentially interacts with engineered nanomaterials through the creation of protein coronas, which in turn become primary determinants of both the pharmacokinetics and pharmacodynamics of circulating nanoparticles. Here, for the first time, the specific binding kinetics of the four major corona forming proteins (human serum albumin, fibrinogen, ApoA1, and polyclonal IgG) are determined for gold nanoparticles (AuNPs). Using a multiplexed surface plasmonic assay, highly reproducible measurements of on rate (k(on)), off rate (k(off)), and disassociation constant (K(D)), in addition to relative amounts of protein binding, are obtained.

Attachment-related biases in adolescents' memory.

Attachment theorists propose that individuals' internal working models influence their social information processing. This study explored links between attachment representations and social information processing by examining adolescents' (n = 189; Mage  = 16.5 years) attachment-related memory biases.

Graphene Multi-Walled Carbon Nanotubes for Electrochemical Glucose Biosensing.

A simple procedure was developed for the fabrication of electrochemical glucose biosensors using glucose oxidase (GOx), with graphene or multi-walled carbon nanotubes (MWCNTs). Graphene and MWCNTs were dispersed in 0.25% 3-aminopropyltriethoxysilane (APTES) and drop cast on 1% KOH-pre-treated glassy carbon electrodes (GCEs).

The development of negative reactivity in irritable newborns as a function of attachment.

This longitudinal study builds on existing research exploring the developmental course of infants' negative reactivity to frustration in a sample of 84 irritable infants. We investigated whether infants' negative reactivity to frustration differed during the first year as a function of infant attachment classification. Various elements of the designs of previous studies investigating negative reactivity and attachment preclude the strong conclusion that negative reactivity develops differently as a function of attachment.

Tipping points in adolescent adjustment: predicting social functioning from adolescents' conflict with parents and friends.

Despite widespread interest in examining the role of conflict for adolescent development, researchers only rarely have examined adolescents' experiences of conflict across relationships. The present study examined how adolescents' experiences of conflict with parents and friends were linked to their social functioning. Adolescents (n = 189) and their mothers and fathers participated in semistructured discussions about areas of parent-adolescent conflict in the laboratory.

Attachment-related differences in perceptions of an initial peer interaction emerge over time: evidence of reconstructive memory processes in adolescents.

This study examined whether attachment, assessed using the Adult Attachment Interview (AAI; George, Kaplan, & Main, 1996) was linked to how adolescents reconstructed their memory for an initial interaction with an unfamiliar peer. Adolescents (N = 189, 62% female) completed a 10-min laboratory task with a student whom they did not know. Immediately following this task, adolescents rated their perceptions of the interaction.

Links between attachment and social information processing: examination of intergenerational processes.

This chapter describes theory and research on intergenerational connections between parents' attachment and children's social information processing, as well as between parents' social information processing and children's attachment. The chapter begins with a discussion of attachment theorists' early insights into the role that social information processing plays in attachment processes. Next, current theory about the mechanisms through which cross-generational links between attachment and social information processing might emerge is presented.

Reporter discrepancies among parents, adolescents, and peers: adolescent attachment and informant depressive symptoms as explanatory factors.

The issue of informant discrepancies about child and adolescent functioning is an important concern for clinicians, developmental psychologists, and others who must consider ways of handling discrepant reports of information, but reasons for discrepancies in reports have been poorly understood. Adolescent attachment and informant depressive symptoms were examined as 2 explanations for absolute and directional discrepancies about adolescent symptoms, relationships, and social behavior in a sample of 189 eleventh-grade students (mean age=16.5 years).

Attachment and the processing of social information across the life span: theory and evidence.

Researchers have used J. Bowlby's (1969/1982, 1973, 1980, 1988) attachment theory frequently as a basis for examining whether experiences in close personal relationships relate to the processing of social information across childhood, adolescence, and adulthood. We present an integrative life-span-encompassing theoretical model to explain the patterns of results that have emerged from these studies.

Do adolescents and parents reconstruct memories about their conflict as a function of adolescent attachment?

This study examined whether 17-year-old adolescents (n=189) and their parents reconstructed their memory for an adolescent-parent laboratory conflict over a 6-week period as a function of adolescent attachment organization. It also compared participants' perceptions of conflict over time to observational ratings of the conflict to further characterize the nature of the attachment-related memory biases that emerged. Secure adolescents reconstructed interactions with each parent more favorably over time, whereas insecure adolescents showed less favorable reconstructive memory.

Perceptions of secure base provision within the family.

The present study examined three sets of questions about secure base provision in the context of the family, including (1) relations between inter-parental perceptions of secure base provision and parents' adult romantic attachment and marital satisfaction, (2) interrelations among family members' perception of secure base provision, and (3) links between both adolescents' and parents' perceptions of secure base provision and adolescent symptoms. Participants were 189 adolescents from two-parent families (mean age = 17 years; 118 girls) and their parents. We found partial support for theorized links between perceptions of spousal secure base provision and spousal romantic attachment, as well as full support for expected associations between secure base provision and marital satisfaction.

Attachment and peer relations in adolescence.

The aim of this investigation was to examine whether adolescent attachment representation (as assessed using the Adult Attachment Interview) is linked to the quality of adolescents' peer relations (as assessed using a standard battery of peer-report instruments tapping adolescents' social behaviors, peer victimization, social acceptance, and sociometric status). As expected, secure/autonomous adolescents were more likely than insecure/dismissing adolescents to be perceived as behaving prosocially, and less likely to be perceived as aggressive, shy-withdrawn, and victimized by peers. Other findings indicated that insecure/dismissing adolescents, compared to secure/autonomous adolescents, were less likely to be socially accepted by their peers.

Narrative assessment of attachment representations: links between secure base scripts and adolescent attachment.

We explored the notion that adolescents possess mental secure base scripts of attachment-related events and examined, for the first time, whether these scripts were linked to adolescent attachment security. Results indicated that adolescents possessed a general script for mother and for father, and that they drew upon these scripts across different contexts. Adolescents' scripts for mother and for father were related, but only the scripts for mother predicted unique variance in adolescents' scripts for nonspecific others.