Preparation and characterisation of silica‐based nanoparticles for cisplatin release on cancer brain cells

In the present work, the preparation, characterisation, and efficiency of two different silica nanostructures as release vehicles of Cisplatin are reported. The 1‐hexadeciltrimethyl‐ammonium bromide templating agent was used to obtain mesoporous silica nanoparticles which were later loaded with Cisplatin. While sol–gel silica was very fast prepared using an excess of acetic acid during the hydrolysis–condensation reactions of tetraethylorthosilicate and at the same time the Cisplatin was added. Several physicochemical techniques including spectroscopies, electronic microscopy, X‐ray diffraction, N₂ adsorption–desorption were used to characterise the silica nanostructures. An in vitro Cisplatin release test was carried out using artificial cerebrospinal fluid. Finally, the toxicity of all silica nanostructures was tested using the C6 cancer cell line. The spectroscopic results showed the suitable stabilisation of Cisplatin into the two different silica nanostructures. A large surface area was obtained for the mesoporous silica nanoparticles, while low areas were obtained in the silica nanoparticles. Cisplatin was released faster from mesoporous silica channels than from inside of aggregates nanoparticles silica. Cisplatin alone, as well as, cisplatin released from both silica nanostructures exerted a toxic effect on cancer cells. In contrast, both silica structures without the drug did not exert any toxic effect.Inspec keywords: cellular biophysics, desorption, adsorption, biomedical materials, sol‐gel processing, silicon compounds, cancer, toxicology, nanofabrication, brain, condensation, mesoporous materials, nanoparticles, X‐ray diffraction, nanomedicine, drugs, aggregates (materials)Other keywords: mesoporous silica channels, silica‐based nanoparticles, cancer brain cells, silica nanostructures, 1‐hexadeciltrimethyl‐ammonium bromide, mesoporous silica nanoparticles, sol‐gel silica, C6 cancer cell line, in vitro cisplatin release test, C6 cancer cell line, acetic acid, hydrolysis‐condensation reactions, tetraethylorthosilicate, physicochemical techniques, electronic microscopy, X‐ray diffraction, N₂ adsorption‐desorption, artificial cerebrospinal fluid, toxicity, toxic effect, N₂ , SiO₂      

Morphosynthesis and morphology characterization of aniline and aniline/Laponite films

We report on morphosynthesis techniques that have been employed to tune polyamine film nanoarchitectures and on their resulting morphologies. Specific layers discussed include films of aniline/Laponite clay and aniline solution processed with V₂O₅ catalyst. Synthesis approaches examined include films generated in-situ (glass templating), solution based drop casting, and mechanochemical grinding. Surface topography results suggest that these approaches provide dimensionality control of the polyaniline morphology. Surface images of the mechanochemically ground polyaniline/Laponite nanocomposite layer reveal interfacial contact which is promising for potential heterojunction solar cell designs.     

Effects of repeated practice and contextual-writing experiences on college students' writing skills.

The authors examined the effects of both general and task-specific writing experiences on college students' writing-skill development. On the basis of theories of expertise development and a cognitive process theory of writing-skill development, the authors predicted that repeated practice would be associated with superior writing skills and that after controlling for repeated practice, writing within a specific task domain would be associated with superior writing skills. Undergraduate students participated in a field experiment in which 279 students practiced their writing skills in a professionally relevant task domain, whereas another group of 385 students practiced their writing skills in a more general domain. The results were consistent with the predictions. The authors discuss implications for teaching writing skills and for general theories of expertise development in writing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Zirconium oxide nanotube surface prompts increased osteoblast functionality and mineralization

Electrochemical formation of tunable nanoscale oxide layers on biomedical metallic surfaces has recently drawn much attention in biomaterials research. In this study, we report on the cellular response to a unique vertically aligned, laterally spaced nanotube nanostructure made of zirconium oxide (ZrO₂) fabricated by anodization. The growth, morphology, and functionality of osteoblasts cultured on ZrO₂ nanotubes have been investigated. The initial adhesion and spreading was considerably improved on the nanotube surface as compared to a flat zirconium (Zr) surface without a nanostructure. The morphology of the adhered cells on the nanotube surface elicited a highly organized cytoskeleton with crisscross patterned actin, which was lacking on the flat Zr. Increased alkaline phosphatase activity levels and the formation of calcified extracellular matrix implied improved osteoblast functionality and mineralization on the nanotube substrate. This in vitro study suggests that the ZrO₂ nanotubes provided an enhanced osteoblast response and demonstrated their apparent role in providing a platform for bone growth.     

Volumetric Properties of 1,1-Dimethylethyl Methyl Ether with Ethyl Acrylate, Butyl Acrylate, Methyl Methacrylate, and Styrene at 298.15 K

Densities of the binary systems of 1,1-dimethylethyl methyl ether (MTBE) with ethyl acrylate, butyl acrylate, methyl methacrylate, and styrene have been measured as a function of the composition, at 298.15 K and atmospheric pressure, using an Anton Paar DMA 5000 oscillating U-tube densimeter. The calculated excess volumes were correlated with the Redlich–Kister equation and with a series of Legendre polynomials. The excess volumes are negative for all the systems studied.     

Effects of a Corneal Anesthetic on Extinction of the Classically Conditioned Nictitating Membrane Response in the Rabbit (Oryctolagus cuniculus).

Rabbits (Oryctolagus cuniculus) were presented with 7 daily sessions of tone-alone training after conditioning. Before the beginning of each of the first 4 extinction sessions, an artificial tear solution or tetracaine hydrochloride was administered to the cornea of rabbits in the control group (n=6) and experimental group (n=1), respectively. There were no between-group differences in the percentage of conditioned responses between both groups. However, the amplitude of the conditioned response was notably reduced in the tetracaine group (M=0.40, SEM±0.216) relative to the control group (M=1.32, SEM ±0.639) early in extinction. Results seem to suggest that although motor output has been found to play an important role in extinction, corneal sensory feedback is not necessary. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The structure of maladaptive personality traits in childhood: A step toward an integrative developmental perspective for DSM-V.

The present study describes the construction of a taxonomy of trait-related symptoms in childhood, the Dimensional Personality Symptom Item Pool (DIPSI), and examines the replicability of the taxonomy's higher order structure across maternal ratings of referred (N = 205) and nonreferred (N = 242) children and self-ratings of adolescents (N = 453). The DIPSI's 4 higher order factors--that is, Emotional Instability, Disagreeableness, Introversion, and Compulsivity--showed clear correspondence with the dimensions of personality pathology found in adulthood (Dimensional Assessment of Personality Pathology-Basic Questionnaire; W. J. Livesley, 1990; Schedule for Nonadaptive and Adaptive Personality; L. A. Clark, 1993). These 4 factors can be further organized into 2 superfactors, representing Internalizing and Externalizing Traits, demonstrating empirical and conceptual relationships with psychopathology models in childhood and adulthood. The implications for the assessment and conceptualization of early trait pathology are discussed in the context of an integrative developmental perspective on the construction of the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Empirically supported treatments: Implications for training.

This article discusses the role of empirically supported treatments (ESTs) in the training of clinical psychologists. Training in ESTs can be integrated in ways that vary depending on the level of training and setting. Predoctoral programs, internships, postdoctoral programs, and continuing education are discussed in regard to special challenges and sequencing of training. A preliminary set of guidelines for training in ESTs is suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Predatory behavior in laboratory mice: Strain and sex comparisons.

Measured latency to attack live crickets in 26 male and 26 female naive, non-food-deprived laboratory mice from a genetically heterogenous stock (HS/Ibg) and in 7 inbred strains (10 male and 10 female Ss for each strain). The HS/Ibg, Is/Crgl, C57BL/Crgl, and C3H/Crgl Ss had the shortest latencies to attack crickets. The RIII/Crgl and BALB/cCrgl Ss were intermediate, while DBA/2Crgl and A/Crgl were slowest. Among the inbred strains sex differences were nonexistent or inconsistent from strain to strain. However, HS/Ibg males were more likely to attack than were females. Enough females attack for cricket killing to be a useful form of attack behavior for genetic experiments. In nearly all Ss latency decreased from the 1st to the 2nd trial, indicating that cricket killing is rapidly learned in adult mice of a wide variety of genotypes. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)