Nanoparticle passage through porcine jejunal mucus: Microfluidics and rheology.

A micro-slide chamber was used to screen and rank sixteen functionalized fluorescent silica nanoparticles (SiNP) of different sizes (10, 50, 100 and 200 nm) and surface coatings (aminated, carboxylated, methyl-PEG1000ylated, and methyl-PEG2000ylated) according to their capacity to permeate porcine jejunal mucus. Variables investigated were influence of particle size, surface charge and methyl-PEGylation. The anionic SiNP showed higher transport through mucus whereas the cationic SiNP exhibited higher binding with lower transport. A size-dependence in transport was identified - 10 and 50 nm anionic (uncoated or methyl-PEGylated) SiNP showed higher transport compared to the larger 100 and 200 nm SiNP. The cationic SiNP of all sizes interacted with the mucus, making it more viscous and less capable of swelling. In contrast, the anionic SiNP (uncoated or methyl-PEGylated) caused minimal changes in the viscoelasticity of mucus. The data provide insights into mucus-NP interactions and suggest a rationale for designing oral nanomedicines with improved mucopermeability.

Synthetic multivalency for biological applications.

Current directions and emerging possibilities under investigation for the integration of synthetic and semi-synthetic multivalent architectures with biology are discussed. Attention is focussed around multivalent interactions, their fundamental role in biology, and current and potential approaches in emulating them in terms of structure and functionality using synthetic architectures.

Surfactant titration of nanoparticle-protein corona.

Nanoparticles (NP), when exposed to biological fluids, are coated by specific proteins that form the so-called protein corona. While some adsorbing proteins exchange with the surroundings on a short time scale, described as a "dynamic" corona, others with higher affinity and long-lived interaction with the NP surface form a "hard" corona (HC), which is believed to mediate NP interaction with cellular machineries. In-depth NP protein corona characterization is therefore a necessary step in understanding the relationship between surface layer structure and biological outcomes. In the present work, we evaluate the protein composition and stability over time and we systematically challenge the formed complexes with surfactants. Each challenge is characterized through different physicochemical measurements (dynamic light scattering, ζ-potential, and differential centrifugal sedimentation) alongside proteomic evaluation in titration type experiments (surfactant titration). 100 nm silicon oxide (Si) and 100 nm carboxylated polystyrene (PS-COOH) NPs cloaked by human plasma HC were titrated with 3-[(3-Cholamidopropyl) dimethylammonio]-1-propanesulfonate (CHAPS, zwitterionic), Triton X-100 (nonionic), sodium dodecyl sulfate (SDS, anionic), and dodecyltrimethylammonium bromide (DTAB, cationic) surfactants. Composition and density of HC together with size and ζ-potential of NP-HC complexes were tracked at each step after surfactant titration. Results on Si NP-HC complexes showed that SDS removes most of the HC, while DTAB induces NP agglomeration. Analogous results were obtained for PS NP-HC complexes. Interestingly, CHAPS and Triton X-100, thanks to similar surface binding preferences, enable selective extraction of apolipoprotein AI (ApoAI) from Si NP hard coronas, leaving unaltered the dispersion physicochemical properties. These findings indicate that surfactant titration can enable the study of NP-HC stability through surfactant variation and also selective separation of certain proteins from the HC. This approach thus has an immediate analytical value as well as potential applications in HC engineering.

Multivalent recognition of concanavalin A by {Mo132 } glyconanocapsules--toward biomimetic hybrid multilayers.

Herein, we consider Müller's spherical, porous, anionic, molybdenum oxide based capsule, (NH4)42[{(Mo(VI))Mo(VI)5O21(H2O)6}12{Mo(V)2O4(CH3COO)}30]⋅10 CH3COONH4⋅300 H2O≡(NH4)42⋅1 a⋅crystal ingredients≡1, {Mo132}, as an effective sugar-decorated nanoplatform for multivalent lectin recognition. The ion-exchange of NH4(+) ions of 1 with cationic-sugars, D-mannose-ammonium chloride (2) or D-glucose-ammonium chloride (3) results in the formation of glyconanocapsules (NH4)(42-n)2n⋅1 a and (NH4)(42-m)3m⋅1 a. The Mannose (NH4)(42-n)2n⋅1 a capsules bind selectively Concanavalin A (Con A) in aqueous solution, giving an association avidity constant of K(a)(multi)=4.6×10(4) M(-1) and an enhancement factor of ß=K(a)(multi)/K(ass)(mono)=21.9, reminiscent of the formation of "glycoside clusters" on the external surface of glyconanocapsule. The glyconanocapsules (NH4)(42-n)2n⋅1 a and (NH4)(42-m)3m⋅1 a self-assemble in "hybrid multilayers" by successive layer-by-layer deposition of (NH4)(42-n)2n⋅1 a or (NH4)(42-m)3m⋅1 a and Con A. These architectures, reminiscent of versatile mimics of artificial tissues, can be easily prepared and quantified by using quartz crystal microgravimetry (QCM). The "biomimetic hybrid multilayers" described here are stable under a continual water flow and they may serve as artificial networks for a greater depth of understanding of various biological mechanisms, which can directly benefit the fields of chemical separations, sensors or storage-delivery devices.

The biomolecular corona is retained during nanoparticle uptake and protects the cells from the damage induced by cationic nanoparticles until degraded in the lysosomes.

Nanoparticles have unique capacities of interacting with the cellular machinery and entering cells. To be able to exploit this potential, it is essential to understand what controls the interactions at the interface between nanoparticles and cells: it is now established that nanoparticles in biological media are covered by proteins and other biomolecules forming a "corona" on the nanoparticle surface, which confers a new identity to the nanoparticles. By labelling the proteins of the serum, using positively-charged polystyrene, we now show that this adsorbed layer is strong enough to be retained on the nanoparticles as they enter cells and is trafficked to the lysosomes on the nanoparticles. There, the corona is degraded and this is followed by lysosomal damage, leading to cytosolic release of lysosomal content, and ultimately apoptosis. Thus the corona protects the cells from the damage induced by the bare nanoparticle surface until enzymatically cleared in the lysosomes. FROM THE CLINICAL EDITOR: This study investigates the effects of protein corona that normally forms on the surface of nanoparticles during in vivo use, describing the steps of intracellular processing of such particles, to enhance our understanding of how these particles interact with the cellular machinery.

Dynamic nanoplatforms in biosensor and membrane constitutional systems.

Molecular recognition in biological systems occurs mainly at interfacial environments such as membrane surfaces, enzyme active sites, or the interior of the DNA double helix. At the cell membrane surface, carbohydrate-protein recognition principles apply to a range of specific non-covalent interactions including immune response, cell proliferation, adhesion and death, cell-cell interaction and communication. Protein-protein recognition meanwhile accounts for signalling processes and ion channel structure. In this chapter we aim to describe such constitutional dynamic interfaces for biosensing and membrane transport applications. Constitutionally adaptive interfaces may mimic the recognition capabilities intrinsic to natural recognition processes. We present some recent examples of 2D and 3D constructed sensors and membranes of this type and describe their sensing and transport capabilities.

Dynamic hybrid materials for constitutional self-instructed membranes.

Constitutional self-instructed membranes were developed and used for mimicking the adaptive structural functionality of natural ion-channel systems. These membranes are based on dynamic hybrid materials in which the functional self-organized macrocycles are reversibly connected with the inorganic silica through hydrophobic noncovalent interactions. Supramolecular columnar ion-channel architectures can be generated by reversible confinement within scaffolding hydrophobic silica mesopores. They can be structurally determined by using X-ray diffraction and morphologically tuned by alkali-salts templating. From the conceptual point of view, these membranes express a synergistic adaptive behavior: the simultaneous binding of the fittest cation and its anion would be a case of "homotropic allosteric interactions," because in time it increases the transport efficiency of the pore-contained superstructures by a selective evolving process toward the fittest ion channel. The hybrid membranes presented here represent dynamic constitutional systems evolving over time to form the fittest ion channels from a library of molecular and supramolecular components, or selecting the fittest ion pairs from a mixture of salts demonstrating flexible adaptation.

The uncanny in a dream.

In previous publications, the author has focused on particular types of inclusions in dreams (Mahon 2002a, 2002b, 2005a, 2007). In this paper, the author explores an instance of the uncanny in a dream and speculates on the particular function such an inclusion might have served. A patient dreamed about the name of an author, Thomas B. Costain, which he believed at first to be a fictitious dream concoction. In fact, all his initial associations dealt with this dream inclusion as if it had no connection to reality. When he later Googled the name, he was surprised to uncannily discover that the "fictitious" name was in fact the real name of a moderately well-known author. His subsequent discovery-that one of the author's books, The Silver Chalice, "re-minded" him of silver paper chalices that his father used to make for him as a child-jolted him further. This revived repression of not only the author's name, but also of its significant connection to repressed genetic memories, filled him with a sense of awe, as though he had suddenly been awakened from a hypnotic spell. If dream experience in general can be considered uncanny, the dream work deployed this particular inclusion of an uncanny, "fictitious" representation of reality for complex dynamic reasons, the author maintains.

The spit and image: a psychoanalytic dissection of a colloquial expression.

"He is the spit of his father" or "he is the spit and image of his father" is a colloquial expression that has graced informal English for many centuries. When a "spitting image" made an entrance in the manifest content of an analysand's dream, it became possible to add a psychoanalytic point of view to an etymological and anthropological record. After discussing both this clinical case and an "anthropological case history," the author examines the subtle but complex genesis of this colloquial expression from a speculative applied psychoanalytic perspective.

Play, Free Association, and Enactment.

In this article I define childhood symbolic play, free association, and enactments as distinct entities despite the important strands of connective tissue that bind them psychologically. To Freud's definition of play being the same as fantasy, except for play's need to use props and playthings to actualize itself, I add action as an obvious but yet nevertheless neglected component of childhood symbolic play. I suggest that the potential for free association begins with the achievement of formal Piagetian cognitive processes in early adolescence, an achievement that needs no props or actions to set it in motion since words and ideas generate further spontaneities in a creative flow of associations. In adult psychoanalytic process, I define enactment, not only in the modern sense of a shared unconscious communication that illustrates the complementarity of countertransference/transference mutuality, but as if enactment could be isolated from its enmeshment in the countertransference/transference milieu of analytic process and viewed momentarily as a transference entity exclusively. I take this point of view to emphasize longitudinally, an individual's action in a developmental sequence, an imaginary developmental line from the six stages of sensorimotor actions that lead to symbolism, to thought as trial action, leading on then to symbolic play and to free association in adolescence, free associative communication being the essential core of analytic process despite the ubiquity of enactments that accompany it. I illustrate this imagined developmental line, which leads from the earliest sensorimotor acts to the decisive non-neurotic acts that characterize individuated post-analytic maturity, with psychoanalytic process from childhood, adolescence, and adulthood.

The Evolution of Dreams: A Fifty Year Follow-Up.

A child that was analyzed from four years of age to nine returned for brief visits at age twelve, nineteen, thirty; and at fifty for a more sustained analytic engagement. He reported new dreams on each return visit. Given this contact with him for almost fifty years it has been possible to reflect on the progression of his dreams over five decades. While it is clear that dreams do reflect developmental challenges there is also a remarkable continuity of genetic themes that can be identified. While dreams do reflect different phases of development, to be sure, the persistence of initial genetic conflicts are not only reflected in symptoms and character structure but in the dream work's artistry as well, as latent content is transformed so creatively into its manifest disguises. It is this striking continuity of original genetic themes, first exposed in the child analysis, that runs like the unconscious musical drone of a ground bass throughout the first fifty years of the symphonic life of one individual, that I wish to focus on.

A Cartoon in a Dream.

A cartoon in a dream is an unusual example of an inclusion body, so to speak, planted in manifest content by the dream-work to attract special attention to what is manifest, when what is latent is in danger of exposing itself too radically. In previous publications the author has described similar, unusual, conspicuous insertions in dreams (a joke in a dream; a pun in a dream; a parapraxis in a dream; a trick in a dream; the uncanny in dreams; dreams within dreams). In all of these instances it was possible, using the free associative method of dream analysis, to lay bare the dynamic architecture of each dream and expose what the manifest razzle-dazzle of the intruding element sought to achieve. It was often the case that such elements were a last minute heroic attempt on the part of the dream-work to save an explosive dream from falling apart as highly combustible, sexual, or aggressive elements could not be reined in sufficiently to escape the dream censor's vetoing disapproval. In the current example a rather vivid cartoon image took center stage, hoping to keep the focus entirely on manifest content and leave the latent content unexamined even when the awakener begins to analyze the dream.

Silica-Coated Nanoparticles with a Core of Zinc, l-Arginine, and a Peptide Designed for Oral Delivery.

Nanoparticle constructs for oral peptide delivery at a minimum must protect and present the peptide at the small intestinal epithelium in order to achieve oral bioavailability. In a reproducible, scalable, surfactant-free process, a core was formed with insulin in ratios with two established excipients and stabilizers, zinc chloride and l-arginine. Cross-linking was achieved with silica, which formed an outer shell. The process was reproducible across several batches, and physicochemical characterization of a single batch was confirmed in two independent laboratories. The silica-coated nanoparticles (SiNPs) entrapped insulin with high entrapment efficiency, preserved its structure, and released it at a pH value present in the small intestine. The SiNP delivered insulin to the circulation and reduced plasma glucose in a rat jejunal instillation model. The delivery mechanism required residual l-arginine in the particle to act as a permeation enhancer for SiNP-released insulin in the jejunum. The synthetic process was varied in terms of ratios of zinc chloride and l-arginine in the core to entrap the glucagon-like peptide 1 analogue, exenatide, and bovine serum albumin. SiNP-delivered exenatide was also bioactive in mice to some extent following oral gavage. The process is the basis for a platform for oral peptide and protein delivery.

The death of Hamnet: an essay on grief and creativity.

The author argues that Shakespeare's Hamlet (1600) was influenced by the death in 1596 of the playwright's 11-year-old twin son, Hamnet. Beyond the similarity between the dead child's name and the play's title, the language of the play, a supreme act of sublimation, does at times seem preoccupied with a kind of linguistic twinning. The play's variations on the theme of doubling-pairs of characters, for example, and the many instances of hendiadys, a figure of speech using two substantives to denote a single complex meaning, as well as Hamlet's play within a play-are indirect references to the dead twin, the author contends.

Seeing the light.

Seeing the light is an expression that usually connotes a conceptual grasp of meaning in all its complexity, while the perception of light is not the issue. In this paper, the authors present a patient with an exquisite light sensitivity that disturbs her sleep; she is "seeing the light" in a symptomatic, concrete way. Light itself has become a compliant and collusive element onto which an aspect of conflict is displaced in the service of self-deception. Ironically, the analysis and deconstruction of the symptom eventually led to the kind of insight that the expression seeing the light conveys.

Characterization of Nanoparticle Batch-To-Batch Variability.

A central challenge for the safe design of nanomaterials (NMs) is the inherent variability of NM properties, both as produced and as they interact with and evolve in, their surroundings. This has led to uncertainty in the literature regarding whether the biological and toxicological effects reported for NMs are related to specific NM properties themselves, or rather to the presence of impurities or physical effects such as agglomeration of particles. Thus, there is a strong need for systematic evaluation of the synthesis and processing parameters that lead to potential variability of different NM batches and the reproducible production of commonly utilized NMs. The work described here represents over three years of effort across 14 European laboratories to assess the reproducibility of nanoparticle properties produced by the same and modified synthesis routes for four of the OECD priority NMs (silica dioxide, zinc oxide, cerium dioxide and titanium dioxide) as well as amine-modified polystyrene NMs, which are frequently employed as positive controls for nanotoxicity studies. For 46 different batches of the selected NMs, all physicochemical descriptors as prioritized by the OECD have been fully characterized. The study represents the most complete assessment of NMs batch-to-batch variability performed to date and provides numerous important insights into the potential sources of variability of NMs and how these might be reduced.

A poem and a dream.

Recently, a journalist in analysis had a dream that stimulated the writing of a poem, the two psychic products occurring no more than a few hours apart. Since the analysand had copious free associations to both products, believing both to be culled from the same unconscious raw material, an interesting study of an act of aesthetic creation almost in statu nascendi became possible. A concept called poem work is entertained in this paper and is compared and contrasted with the classical psychoanalytic concept of dream work, allowing some unanswerable questions to be posed and discussed in regard to the formal constitutive elements of poetry.

AFFECT, SYMPTOM, FANTASY, DREAM: CLINICAL AND THEORETICAL CONSIDERATIONS.

A symptom being studied in the process of analysis can be seen as not unlike the unconscious affect it sprang from. The author presents a case in which a symptom, premature ejaculation, was analogous to the unconscious affect of guilt, which itself seemed to be a premature defensive transformation of a deeper current of anger. Guilt was interpreted as if it were a psychic premature ejaculation, a defensive derailment of anger. Fantasy and dream seemed to be engaged in similar transformations, with a fantasy of "premature incarceration" not unlike the symptom itself in its analogous functioning. Analysis of affect, symptom, fantasy, and dream in complex, integrative analytic process led not only to resolution of the symptom itself, but also to a deeper understanding of the mind's complex functioning in general.

The invention of purgatory: a note on the historical pedigree of the superego.

Stoppard (1998) in his great play "The Invention of Love" has suggested that the love poem "Like everything else, like clocks and trousers and algebra . . had to be invented" (emphasis added). In this essay I argue that the concept of Purgatory was not always with us either but also had to be invented. If theology got the concept started, I suggest that eventually it may have found its way into psychology, even influencing psychoanalytic ideas about the origins of the Superego. If the concepts Heaven and Hell reflect primitive Superego absolutes, the concept of Purgatory seems like the primitive Superego modulating its own severity and becoming more mature in the process. This influence of a theological concept (Purgatory) on a psychoanalytic concept (Superego) is then outlined and explicated in some detail.