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Metamorphosis (Gr. meta- 'change' + morphe 'form') as a biological process is generally attributed to a subset of animals: most famously insects and amphibians, but some fish and many marine invertebrates as well. We held a symposium at the 2006 Society for Integrative and Comparative Biology (SICB) annual meeting in Orlando, FL (USA) to discuss metamorphosis in a comparative context. Specifically, we considered the possibility that the term 'metamorphosis' could be rightly applied to non-animals as well, including fungi, flowering plants, and some marine algae. Clearly, the answer depends upon how metamorphosis is defined. As we participants differed (sometimes quite substantially) in how we defined the term, we decided to present each of our conceptions of metamorphosis in 1 place, rather than attempting to agree on a single consensus definition. Herein we have gathered together our various definitions of metamorphosis, and offer an analysis that highlights some of the main similarities and differences among them. We present this article not only as an introduction to this symposium volume, but also as a reference tool that can be used by others interested in metamorphosis. Ultimately, we hope that this article--and the volume as a whole--will represent a springboard for further investigations into the surprisingly deep mechanistic similarities among independently evolved life cycle transitions across kingdoms.

Binary hybrids have been investigated for the past few decades due to the emerging properties of nanoparticle composites. Electrostatically stabilized core–shell nanostructures composed of surface active magnetic nanoparticles (SAMNs) and differently charged carbon nanomaterials display specific electrochemical properties. In this work, a set of binary hybrids that include a new class of magnetic nanoparticles is presented and the electrochemical features of the hybrids are reported. Gallic acid derived carbon dots (GA-CDs), PEG derived graphene dots (PEG-GDs), and quaternized carbon dots (Q-CDs) characterized by different charged groups were used for the preparation of different complexes with SAMNs. Thus, a set of six binary nanomaterials was obtained, and characterized by electrochemical impedance spectroscopy, cyclic voltammetry and chronoamperometry, demonstrating significant differences in the charge transfer resistance, capacitive current, electrochemical performance, and reversibility with respect to the isolated subunits. Among them, the combination of Q-CDs with an excess of SAMNs led to a Q-CD@SAMN hybrid, which displayed peculiar electrocatalytic properties attributable to the influence of the strong electrostatic interactions exerted by Q-CDs on the SAMN surface. Notwithstanding their small fraction (around 1% w/w), Q-CDs oriented the electrocatalysis of SAMNs toward the selective electro-oxidation of polyphenols at low applied potentials (+0.1 V vs. SCE). Finally, the Q-CD@SAMN hybrid was used for the development of a coulometric sensor for polyphenols, composed of a simple carbon paste electrode in a small volume electrochemical flow cell (1 μL), and used for the complete direct electro-oxidation of polyphenols from plant extracts. [ABSTRACT FROM AUTHOR]

Molecular, developmental, and anatomical evidence support the monophyly of phoronids and brachiopods. However, discrepancies remain regarding the homology of larval neuromuscular characters and their fate at metamorphosis. Despite differences in life history traits, phoronid larvae and the brachiopod larvae of Glottidia pyramidata (linguliform) and Terebratalia transversa (rhynchonelliform) each exhibit two functional neuromuscular signaling centers at metamorphic competence. In phoronids, the larval and presumptive juvenile neuromuscular signaling centers develop separately and have discrete functional roles during metamorphic remodeling. Glottidia pyramidata larvae integrate these neuromuscular centers earlier in development than do phoronid larvae and gradually remodel feeding structures of the planktonic larva into the benthic juvenile form. Competent larvae of Terebratalia transversa have several unique anatomical features consistent with the switch to a non-feeding larval form but still possess two neuromuscular signaling centers with similar functional roles to that of phoronid and Glottidia larvae. Metamorphosis of Terebratalia larvae results in several juvenile neuromuscular features reminiscent of the morphology of Glottidia larvae. Juvenile anatomical features of phoronids and brachiopods diverge morphologically and functionally as the adult ontogenetic program of each juvenile form progresses. Overall, the larval and juvenile neuromuscular anatomy of phoronids and brachiopods share a ground plan that has been modified in developmental timing through heterochrony and functionally modified by adult habitat diversification.

Neuromuscular anatomy and the cytology of the presumptive juvenile tissues of cyclostomate and gymnolaemate bryozoan larvae were investigated with immunohistochemistry, cLSM, SEM, and TEM. Differences in the neuromuscular systems among systematic groups correlate with modifications of swimming and crawling orientations. Ctenostome bryozoans have diversified the size, shape, number, and cytological make-up of the swimming cells more than other morphological grades of bryozoans. Among all non-feeding larval types, there is also a functional relationship between body volume and the surface area of locomotory cilia. Despite anatomical differences, there are shared larval traits that are concordant with 'super-family' level groupings based on adult characters. Overall, the larval body of bryozoans consists of two regions that have been modified several times in terms of their larval function and their relative contributions to juvenile tissue. Considering the pre- and postrochal regions present in phyla with a trochophore larva and the larval body regions of other lophotrochozoans, it is plausible that a bipartite larval body is plesiomorphic for lophotrochozoans.

Non-feeding larval forms produced by bryozoans are ideal for testing hypotheses regarding the functional designs for swimming in the plankton due to their diverse cytological architecture yet overall simplified shape. Previous work has shown that the structure of the presumptive juvenile tissues are generally conserved among systematic groupings, however the cytological arrangement and morphology of the multiciliated coronal (larval) cells has been modified several times. The ctenostome bryozoans exhibit the greatest degree of cytological diversity possessing forms that appear functionally convergent with and divergent from other bryozoan systematic groups. It has been demonstrated previously that the coronal cilia of cyphonautes larvae increase in length during development (maximum length of 60 microns), however most non-feeding bryozoan larvae are more extensively ciliated and each cilium is usually a third of this length. My investigations of tethered larvae with high-speed video microscopy have found that cilia of non-feeding forms have higher velocities at their tips than do locomotory cilia of similar length of other larval forms. These new observations also show that turning behaviors are at least partially the result of localized ciliary arrests. Confocal microscopy used in conjunction with fluorescent probes for F-actin and tubulin has resolved patterns in the larval neuromuscular system in relation to locomotory structures. Sensory cells positioned between and adjacent to coronal cells (intercoronal cells and ocelli) are at least bipolar neurons that directly connect with the equatorial nerve ring. These data along with previous descriptions of gap junctions among sensory cells and their effectors as well as the behavioral switches induced by neurotransmitters allow for the development of a model of larval swimming.

We describe the clinical, laboratory, and radiographic characteristics of 15 cases of eastern equine encephalitis in children during 1970-2010. The most common clinical and laboratory features were fever, headache, seizures, peripheral leukocytosis, and cerebrospinal fluid neutrophilic pleocytosis. Radiographic lesions were found in the basal ganglia, thalami, and cerebral cortex. Clinical outcomes included severe neurologic deficits in 5 (33%) patients, death of 4 (27%), full recovery of 4 (27%), and mild neurologic deficits in 2 (13%). We identify an association between a short prodrome and an increased risk for death or for severe disease. [ABSTRACT FROM AUTHOR]

Tyrosine hydroxylase deficiency, a cause of the autosomal recessive form of L-DOPA responsive dystonia, has been associated with a broad spectrum of movement disorders and clinical courses. We describe a new patient presenting with an early onset spastic paraplegia who later developed a progressive generalized dystonic-dyskinetic syndrome. He markedly improved with a very low dosage of L-DOPA/carbidopa, while higher dosages were not tolerated. Two novel mutations (p.G414R/p.L510Q) were detected in the TH gene. [ABSTRACT FROM AUTHOR]

Abstract Background The discovery of the inherited disorders of creatine (Cr) synthesis and transport in the last few years disclosed the importance of blood Cr supply for the normal functioning of the brain. These putatively rare diseases share a common pathogenetic mechanism (the depletion of brain Cr) and similar phenotypes characterized by mental retardation, language disturbances, seizures and movement disorders. In the effort to improve our knowledge on the mechanisms regulating Cr pool inside the nervous tissue, Cr transport and synthesis and related gene transcripts were explored in primary cultures of rat cerebellar granule cells and astrocytes. Methods Cr uptake and synthesis were explored in vitro by incubating monotypic primary cultures of rat type I astrocytes and cerebellar granule cells with: a) D3-Creatine (D3Cr) and D3Cr plus β-guanidinopropionate (GPA, an inhibitor of Cr transporter), and b) labelled precursors of Guanidinoacetate (GAA) and Cr (Arginine, Arg; Glycine, Gly). Intracellular D3Cr and labelled GAA and Cr were assessed by ESI-MS/MS. Creatine transporter (CT1), L-arginine:glycine amidinotransferase (AGAT), and S-adenosylmethionine:guanidinoacetate N-methyltransferase (GAMT) gene expression was assessed in the same cells by real time PCR. Results D3Cr signal was extremely high in cells incubated with this isotope (labelled/unlabelled Cr ratio reached about 10 and 122, respectively in cerebellar granule cells and astrocytes) and was reduced by GPA. Labelled Arg and Gly were taken up by the cells and incorporated in GAA, whose concentration paralleled that of these precursors both in the extracellular medium and inside the cells (astrocytes). In contrast, the increase of labelled Cr was relatively much more limited since labelled Cr after precursors' supplementation did not exceed 2,7% (cerebellar granule cells) and 21% (astrocytes) of unlabelled Cr. Finally, AGAT, GAMT and SLC6A8 were expressed in both kind of cells. Conclusions Our results confirm that both neurons and astrocytes have the capability to synthesize and uptake Cr, and suggest that at least in vitro intracellular Cr can increase to a much greater extent through uptake than through de novo synthesis. Our results are compatible with the clinical observations that when the Cr transporter is defective, intracellular Cr is absent despite the brain should be able to synthesize it. Further research is needed to fully understand to what extent our results reflect the in vivo situation.

Abstract Background Larval features such as the apical organ, apical ciliary tuft, and ciliated bands often complicate the evaluation of hypotheses regarding the origin of the adult bilaterian nervous system. Understanding how neurogenic domains form within the bilaterian head and larval apical organ requires expression data from animals that exhibit aspects of both centralized and diffuse nervous systems at different life history stages. Here, we describe the expression of eight neural-related genes during the larval development of the brachiopod, Terebratalia transversa. Results Radially symmetric gastrulae broadly express Tt-Six3/6 and Tt-hbn in the animal cap ectoderm. Tt-NK2.1 and Tt-otp are restricted to a central subset of these cells, and Tt-fez and Tt-FoxQ2 expression domains are already asymmetric at this stage. As gastrulation proceeds, the spatial expression of these genes is split between two anterior ectodermal domains, a more dorsal region comprised of Tt-Six3/6, Tt-fez, Tt-FoxQ2, and Tt-otp expression domains, and an anterior ventral domain demarcated by Tt-hbn and Tt-NK2.1 expression. More posteriorly, the latter domains are bordered by Tt-FoxG expression in the region of the transverse ciliated band. Tt-synaptotagmin 1 is expressed throughout the anterior neural ectoderm. All genes are expressed late into larval development. The basiepithelial larval nervous system includes three neurogenic domains comprised of the more dorsal apical organ and a ventral cell cluster in the apical lobe as well as a mid-ventral band of neurons in the mantle lobe. Tt-otp is the only gene expressed in numerous flask-shaped cells of the apical organ and in a subset of neurons in the mantle lobe. Conclusions Our expression data for Tt-Six3/6, Tt-FoxQ2, and Tt-otp confirm some aspects of bilaterian-wide conservation of spatial partitioning within anterior neurogenic domains and also suggest a common origin for central otp-positive cell types within the larval apical organs of spiralians. However, the field of sensory neurons within the larval apical organ of Terebratalia is broader and composed of more cells relative to those of other spiralian larvae. These cellular differences are mirrored in the broader spatial and temporal expression patterns of Tt-FoxQ2 and Tt-otp. Corresponding differences in the expression of Tt-hbn, Tt-NK2.1, and Tt-FoxG are also observed relative to their respective domains within the cerebral ganglia of spiralians. Based on these data we argue that the anterior region of the bilaterian stem species included Six3/6, NK2.1, otp, hbn, fez, and FoxQ2 expression domains that were subsequently modified within larval and adult neural tissues of protostome and deuterostome animals.

Surgical teams have available a number of real‐time imaging tools to help identify and locate tumor tissue. Mass spectrometry, is proven capable of producing molecular signatures from resected tissue which, in turn, has long promised to aid in determining if all tissue which exhibits tumorous molecular signatures has been removed. A few groups have pioneered the transitioning of mass spectrometry from research lab to surgical suite and among these are Professor Nathalie Agar's team at Brigham And Women's Hospital ‐ Harvard Medical School, who present our Special Feature. Agar's team have sited an ion trap system with DESI ion source into the Advanced Multimodality Image Guided Operating (AMIGO) suite and show that MS information can play a role in surgical decision making. [ABSTRACT FROM AUTHOR]