Morphological aspects of muscle regeneration in the Nile tilapia (Oreochromis niloticus)

The aim of our study was to analyze the morphological events in the skeletal muscle of the Nile tilapia (Oreochromis niloticus) after a traumatic lesion. Thirty-two fish were used, on which a small longitudinal incision was made in the muscle. The fish were sacrificed after 7, 14, 21, and 42 days and muscle samples were collected from the lesion and processed for morphological analysis. Muscle regeneration in the tilapia occurred gradually through the analyzed period, possibly due to the proliferation and differentiation of myosatellite cells, which were more morphologically evident 7 and 14 days after lesion.

Biocompatibility analysis of Bioglass® 45S5 and Biosilicate® implants in the rabbit eviscerated socket

Purpose: Bioactive glass and bioactive glass-ceramic cone implants were placed in the rabbit eviscerated socket to assess their biocompatibility. Methods: Fifty-one Norfolk albino rabbits underwent evisceration of the right eye followed by implantation of cones made from Bioglass® 45S5 (control group) and two types of bioactive glass-ceramic (Biosilicate®), a single- and a two-phase bioactive glass-ceramic implants into the scleral cavity. Postoperative reactions, animal behavior and socket conditions were monitored daily. Clinical exam, biochemical evaluations, and orbit computed tomographic scan were done at 7, 90, and 180 days post-procedure. After that, the animals were euthanized, and the orbital content was removed and prepared to light microscopy with morphometric evaluation and scanning electron microscopy examination. Statistical analysis was done by parametric and non-parametric analysis of variance, complemented by Dunn's and Tukey's tests (p<0.05). Results: All animals did not develop systemic toxicity throughout the experimental period and also did not have orbit infection, implant migration or extrusion. Morphological analysis demonstrated pseudocapsule around all implants. Bioglass® and single-phase Biosilicate® implants induced less inflammation and pseudocapsule formation than two-phase Biosilicate® cones. Seven days post-procedure, the inflammatory reaction was intense and gradually decreased throughout the experiment. Tissue reaction was least intense in animals receiving Bioglass® implants. Conclusions: We observe discrete differences among the studied materials, with best responses obtained with use of Bioglass® 45S5 and single-phase Biosilicate®. The authors agree these implants might be useful in the management of the anophthalmic socket. © 2012 Informa Healthcare USA, Inc.

The effect of laminin-1-doped nanoroughened implant surfaces: Gene expression and morphological evaluation

Aim. This study aimed to observe the morphological and molecular effect of laminin-1 doping to nanostructured implant surfaces in a rabbit model. Materials and Methods. Nanostructured implants were coated with laminin-1 (test; dilution, 100 g/mL) and inserted into the rabbit tibiae. Noncoated implants were used as controls. After 2 weeks of healing, the implants were removed and subjected to morphological analysis using scanning electron microscopy (SEM) and gene expression analysis using the real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Results. SEM revealed bony tissue attachment for both control and test implants. Real-time RT-PCR analysis showed that the expression of osteoblast markers RUNX-2, osteocalcin, alkaline phosphatase, and collagen I was higher (1.62-fold, 1.53-fold, 1.97-fold, and 1.04-fold, resp.) for the implants modified by laminin-1 relative to the control. All osteoclast markers investigated in the study presented higher expression on the test implants than controls as follows: tartrate-resistant acid phosphatase (1.67-fold), calcitonin receptor (1.35-fold), and ATPase (1.25-fold). The test implants demonstrated higher expression of inflammatory markers interleukin-10 (1.53-fold) and tumour necrosis factor-α (1.61-fold) relative to controls. Conclusion. The protein-doped surface showed higher gene expression of typical genes involved in the osseointegration cascade than the control surface. © 2012 Humberto Osvaldo Schwartz-Filho et al.

Brazilian Angiostrongylus cantonensis haplotypes, ac8 and ac9, have two different biological and morphological profiles

Angiostrongylus cantonensis is the etiologic agent of eosinophilic meningoencephalitis in humans. Cases have been recorded in many parts of the world, including Brazil. The aim of this study was to compare the differences in the biology and morphology of two different Brazilian haplotypes of A. : ac8 and ac9. A significantly larger number of L1 larvae eliminated in the faeces of rodents at the beginning of the patent period was observed for ac9 haplotype and compared to the total of L1 larvae eliminated, there was a significant difference between the two haplotypes. The ac9 haplotype showed a significant difference in the proportion of female and male specimens (0.6:1), but the same was not observed for ac8 (1.2:1). The morphometric analysis showed that male and female specimens isolated from ac8 haplotype were significantly larger with respect to body length, oesophagus length, spicule length (male) and distance from the anus to the rear end (female) compared to specimens from ac9. The morphological analysis by light microscopy showed little variation in the level of bifurcations at the lateral rays in the right lobe of the copulatory bursa between the two haplotypes. The biological, morphological and morphometric variations observed between the two haplotypes agree with the observed variation at the molecular level using the cytochrome oxidase subunit I marker and reinforce the possible influence of geographical isolation on the development of these haplotypes.

Morphological patterns and community organization in leaf-litter ant assemblages

We present a new approach to determine the number and composition of guilds, using the hyperdiverse leaf-litter ant fauna as a model, based on appropriate morphological variables and species co-occurrence null models to describe the complex assemblages of interacting Species Community structure at the 1-m(2) scale. We obtained 18 linear morphometric measures from 949 workers of 171 leaf-litter ant species (18762 measurements) surveyed in four Atlantic Forest localities to test whether the assemblages are morphologically structured; the morphological characters were selected to indicate diet and foraging habits. Principal components analysis was used to characterize the morphospace and to describe the guild structure (number of species and composition). The guild proportionality assembly rule (significant tendency toward constant proportion of species in guilds) was assessed at the 1-m(2) scale. Our analysis indicates that the division of leaf-litter ants into guilds is based mainly on microhabitat distribution in the leaf-litter, body size and shape, eye size, and phylogeny. The same guild scheme applied to four more sites shows that different Atlantic Forest areas have the same leaf-fitter ant guilds. The guild proportionality assembly rule was confirmed for most guilds, Suggesting that there are guild-specific limitations on species coexistence within assemblages; on the other hand, in a few cases the variance in guild proportion was greater than expected under the null assumptions. Other studies on ant functional group classification are partially supported by our quantitative morphological analysis. Our results, however, imply that there are more compartments than indicated in previous models, particularly among cryptic species (confined to soil and litter) and tropical climate specialists. We argue that a general null model for the analysis of species association based oil morphology can reveal objectively defined groups and may thus contribute to a robust theory to explain community structure in general and have important consequences on studies of litter ant community ecology in particular.

TOMOGRAPHIC ANALYSIS FOR C2 SCREW PLACEMENT IN RHEUMATOID ARTHRITIS PATIENTS

Objective: A morphological analysis of the bone structure of 02 in patients with rheumatoid arthritis in order to enhance the security of the stabilization procedures for this vertebra. Methods: We retrospectively analyzed 20 CT scans of the cervical spine performed in patients with rheumatoid arthritis; the following parameters were measured: spinolaminar angle, thickness and length of C2 lamina. Results: The mean values are: 5.92mm and 5.87mm for thickness of right and left laminae retrospectively, 27.75mm for right lamina length and 27.94mm for left lamina length, and 44.7 degrees for spinolaminar angle. Conclusion: The values obtained are consistent with studies in normal subjects published by other groups, with no apparent need for change in the screw placement technique. Level of Evidence IV, Case Series.

Thermal effects and morphological aspects of human dentin surface irradiated with different frequencies of Er:YAG laser

This study reports the effects on micromorphology and temperature rise in human dentin using different frequencies of Er:YAG laser. Sixty human dentin fragments were randomly assigned into two groups (n = 30): carious or sound dentin. Both groups were divided into three subgroups (n = 10), according to the Er:YAG laser frequency used: 4, 6, or 10 Hz (energy: 200 mJ; irradiation distance: 12 mm; and irradiation time: 20 s). A thermocouple adapted to the tooth fragment recorded the initial temperature value (degrees C); then, the temperature was measured after the end of the irradiation (20 s). Morphological analysis was performed using images obtained with scanning electron microscope. There was no difference between the temperatures obtained with 4 and 6 Hz; the highest temperatures were achieved with 10 Hz. No difference was observed between carious and sound dentin. Morphological analyses revealed that all frequencies promoted irregular surface in sound dentin, being observed more selectively ablation especially in intertubular dentin with tubule protrusion. The caries dentin presented flat surface for all frequencies used. Both substrates revealed absence of any signs of thermal damage. It may be concluded that the parameters used in this study are capable to remove caries lesion, having acceptable limits of temperature rise and no significant morphological alterations on dentin surface. Microsc. Res. Tech. 2012. (c) 2012 Wiley Periodicals, Inc.

Surface treatment of dental porcelain with CO2 laser: porosity analysis and AFM.

The effect of CO2 continuous laser irradiation on the surface properties of veneering porcelains has already been tested. The surface observed after laser irradiation is similar to that achieved by auto-glaze in terms of roughness and color parameters (Sgura R, et al. Dental Materials 2011;27(Suppl. 1):e72–73). The purpose of this study was to analyze the surface porosity of porcelain discs after CO2 laser treatment and compare it to auto-glaze treatment, in furnace. A morphological analysis of the porcelain surface was conducted using atomic force microscopy (AFM) and conventional optical microscopy (OM).

Mediterranean brachiopods: morphological, ecological and phylogenetic aspects

The Brachiopoda of the Marine Protected Area “Secche di Tor Paterno”, Central Tyrrhenian Sea, have been investigated in order to give a first glance of the diversity of the brachiopods of this area and provide a new report on the Mediterranean Brachiopod fauna. Four species were reported: Novocrania anomala (Müller, 1776), Megathiris detruncata (Gmelin, 1790), Joania cordata (Risso,1826) and Argyrotheca cuneata (Risso,1826). For all the four species a morphological analysis was carried out. For the two most abundant species, J.cordata and A. cuneata, a morphometric study, based on thickness/width and length/width scattergrams, was carried out, in order to investigate their variability. Size-frequency distributions relative to the three dimensions of the shell were also computed, aimed at a evaluation of population dynamics of these two species. The results showed that, for both species, the parameters which most determine the rise of the shell during the growth of animal are width and length and that frequency distributions are mainly bi- or plurymodal and that they are difficult to interpret, as reported by other studies. Analysis of drill holes found on the shell of some specimens of the two same species revealed a predatory origin and that three different predators are responsible for them. Partial sequences of two different genetic markers, the Internal Transcribed Spacer 1 (ITS1) and the cytochrome oxidase subunit 1 (COI), were used to investigate the phylogenetic relationship between two populations of the eurybathic brachiopod species Gryphus vitreus (Born,1778) across the strait of Gibraltar. This represents the first genetic population study on brachiopods. Results from AMOVA and Bayesian analysis performed on 31 specimens highlighted no genetic differentiation indicating a likely panmixia, dispite the lecitotrophic development of the species.

The role of the intracellular second messenger cAMP in the induction of long-term morphological changes in sensory neurons of {\it Aplysia\/}

The present work examines the role of cAMP in the induction of the type of long-term morphological changes that have been shown to be correlated with long-term sensitization in Aplysia.^ To examine this issue, cAMP was injected into individual tail sensory neurons in the pleural ganglion to mimic, at the single cell level, the effects of behavioral training. After a 22 hr incubation period, the same cells were filled with horseradish peroxidase and 2 hours later the tissue was fixed and processed. Morphological analysis revealed that cAMP induced an increase in two morphological features of the neurons, varicosities and branch points. These structural alterations, which are similar to those seen in siphon sensory neurons of the abdominal ganglion following long-term sensitization training of the siphon-gill withdrawal reflex, could subserve the altered behavioral response of the animal. These results expose another role played by cAMP in the induction of learning, the initiation of a structural substrate, which, in concert with other correlates, underlies learning.^ cAMP was injected into sensory neurons in the presence of the reversible protein synthesis inhibitor, anisomycin. The presence of anisomycin during and immediately following the nucleotide injection completely blocked the structural remodeling. These results indicate that the induction of morphological changes by cAMP is a process dependent on protein synthesis.^ To further examine the temporal requirement for protein synthesis in the induction of these changes, the time of anisomycin exposure was varied. The results indicate that the cellular processes triggered by cAMP are sensitive to the inhibition of protein synthesis for at least 7 hours after the nucleotide injection. This is a longer period of sensitivity than that for the induction of another correlate of long-term sensitization, facilitation of the sensory to motor neuron synaptic connection. Thus, these findings demonstrate that the period of sensitivity to protein synthesis inhibition is not identical for all correlates of learning. In addition, since the induction of the morphological changes can be blocked by anisomycin pulses administered at different times during and following the cAMP injection, this suggests that cAMP is triggering a cascade of protein synthesis, with successive rounds of synthesis being dependent on successful completion of preceding rounds. Inhibition at any time during this cascade can block the entire process and so prevent the development of the structural changes.^ The extent to which cAMP can mimic the structural remodeling induced by long-term training was also examined. Animals were subjected to unilateral sensitization training and the morphology of the sensory neurons was examined twenty-four hours later. Both cAMP injection and long-term training produced a twofold increase in varicosities and approximately a fifty percent increase in the number of branch points in the sensory neuron arborization within the pleural ganglion. (Abstract shortened by UMI.) ^

Metabolic and morphological alterations induced by proteolysis-inducing factor from Walker tumour-bearing rats in C2C12 myotubes

BACKGROUND: Patients with advanced cancer suffer from cachexia, which is characterised by a marked weight loss, and is invariably associated with the presence of tumoral and humoral factors which are mainly responsible for the depletion of fat stores and muscular tissue. METHODS: In this work, we used cytotoxicity and enzymatic assays and morphological analysis to examine the effects of a proteolysis-inducing factor (PIF)-like molecule purified from ascitic fluid of Walker tumour-bearing rats (WF), which has been suggested to be responsible for muscle atrophy, on cultured C2C12 muscle cells. RESULTS: WF decreased the viability of C2C12 myotubes, especially at concentrations of 20-25 mug.mL-1. There was an increase in the content of the pro-oxidant malondialdehyde, and a decrease in antioxidant enzyme activity. Myotubes protein synthesis decreased and protein degradation increased together with an enhanced in the chymotrypsin-like enzyme activity, a measure of functional proteasome activity, after treatment with WF. Morphological alterations such as cell retraction and the presence of numerous cells in suspension were observed, particularly at high WF concentrations. CONCLUSION: These results indicate that WF has similar effects to those of proteolysis-inducing factor, but is less potent than the latter. Further studies are required to determine the precise role of WF in this experimental model. © 2008 Yano et al; licensee BioMed Central Ltd.

Morphological and Phylogenetic Characterization of New Gephyrocapsa Isolates Suggests Introgressive Hybridization in the Emiliania/Gephyrocapsa Complex (Haptophyta)

The coccolithophore genus Gephyrocapsa contains a cosmopolitan assemblage of pelagic species, including the bloom-forming Gephyrocapsa oceanica, and is closely related to the emblematic coccolithophore Emiliania huxleyi within the Noëlaerhabdaceae. These two species have been extensively studied and are well represented in culture collections, whereas cultures of other species of this family are lacking. We report on three new strains of Gephyrocapsa isolated into culture from samples from the Chilean coastal upwelling zone using a novel flow cytometric single-cell sorting technique. The strains were characterized by morphological analysis using scanning electron microscopy and phylogenetic analysis of 6 genes (nuclear 18S and 28S rDNA, plastidial 16S and tufA, and mitochondrial cox1 and cox3 genes). Morphometric features of the coccoliths indicate that these isolates are distinct from G. oceanica and best correspond to G. muellerae. Surprisingly, both plastidial and mitochondrial gene phylogenies placed these strains within the E. huxleyi clade and well separated from G. oceanica isolates, making Emiliania appear polyphyletic. The only nuclear sequence difference, 1 bp in the 28S rDNA region, also grouped E. huxleyi with the new Gephyrocapsa isolates and apart from G. oceanica. Specifically, the G. muellerae morphotype strains clustered with the mitochondrial β clade of E. huxleyi, which, like G. muellerae, has been associated with cold (temperate and sub-polar) waters. Among putative evolutionary scenarios that could explain these results we discuss the possibility that E. huxleyi is not a valid taxonomic unit, or, alternatively the possibility of past hybridization and introgression between each E. huxleyi clade and older Gephyrocapsa clades. In either case, the results support the transfer of Emiliania to Gephyrocapsa. These results have important implications for relating morphological species concepts to ecological and evolutionary units of diversity.

Morphological and Phylogenetic Characterization of New Gephyrocapsa Isolates Suggests Introgressive Hybridization in the Emiliania/Gephyrocapsa Complex (Haptophyta)

The coccolithophore genus Gephyrocapsa contains a cosmopolitan assemblage of pelagic species, including the bloom-forming Gephyrocapsa oceanica, and is closely related to the emblematic coccolithophore Emiliania huxleyi within the Noëlaerhabdaceae. These two species have been extensively studied and are well represented in culture collections, whereas cultures of other species of this family are lacking. We report on three new strains of Gephyrocapsa isolated into culture from samples from the Chilean coastal upwelling zone using a novel flow cytometric single-cell sorting technique. The strains were characterized by morphological analysis using scanning electron microscopy and phylogenetic analysis of 6 genes (nuclear 18S and 28S rDNA, plastidial 16S and tufA, and mitochondrial cox1 and cox3 genes). Morphometric features of the coccoliths indicate that these isolates are distinct from G. oceanica and best correspond to G. muellerae. Surprisingly, both plastidial and mitochondrial gene phylogenies placed these strains within the E. huxleyi clade and well separated from G. oceanica isolates, making Emiliania appear polyphyletic. The only nuclear sequence difference, 1 bp in the 28S rDNA region, also grouped E. huxleyi with the new Gephyrocapsa isolates and apart from G. oceanica. Specifically, the G. muellerae morphotype strains clustered with the mitochondrial β clade of E. huxleyi, which, like G. muellerae, has been associated with cold (temperate and sub-polar) waters. Among putative evolutionary scenarios that could explain these results we discuss the possibility that E. huxleyi is not a valid taxonomic unit, or, alternatively the possibility of past hybridization and introgression between each E. huxleyi clade and older Gephyrocapsa clades. In either case, the results support the transfer of Emiliania to Gephyrocapsa. These results have important implications for relating morphological species concepts to ecological and evolutionary units of diversity.

Sections of the city : architecturalising the tools of urban morphology

The study of urban morphology has become an expanding field of research within the architectural discipline, providing theories to be used as tools in the understanding and design of urban landscapes from the past, the present and into the future. Drawing upon contemporary architectural design theory, this investigation reveals what a sectional analysis of an urban landscape can add to the existing research methods within this field. This paper conducts an enquiry into the use of the section as a tool for urban morphological analysis. Following the methodology of the British school of urban morphology, sections through the urban fabric of the case study city of Brisbane are compared. The results are categorised to depict changes in scale, components and utilisation throughout various timeframes. The key findings illustrate how the section, when read in conjunction with the plan can be used to interpret changes to urban form and the relationship that this has to the quality of the urban environment in the contemporary city.

A new dasyurid marsupial from eastern Queensland, Australia : the buff-footed Antechinus, Antechinus mysticus sp. nov. (Marsupialia: Dasyuridae)

Antechinus mysticus sp. nov. occurs in coastal Australia, ranging from just north of the Queensland (Qld)/New South Wales (NSW) border to Mackay (mid-east Qld), and is sympatric with A. flavipes (Waterhouse) and A. subtropicus Van Dyck & Crowther in south-east Qld. The new species can be distinguished in the field, having paler feet and tail base than A. flavipes and a greyish head that merges to buff-yellow on the rump and flanks, compared with the more uniform brown head and body of A. subtropicus and A. stuartii Macleay. Features of the dentary can also be used for identification: A. mysticus differs from A. flavipes in having smaller molar teeth, from A. subtropicus in having a larger gap between front and rear palatal vacuities, and from A. stuartii in having a generally broader snout. Here, we present a morphological analysis of the new species in comparison with every member of the genus, including a discussion of genetic structure and broader evolutionary trends, as well as an identification key to species based on dental characters. It seems likely that the known geographic range of A. mysticus will expand as taxonomic focus on the genus is concentrated in south-east Queensland and north-east New South Wales.