ACTA OPHTHALMOLOGICA, Issue 2010
KK NISCHAL
Purpose To describe the range of corneal dystrophies presenting to a tertiary refferral paediatric ophthalmology centre and the treatment approach to these various dystrophies Methods Retrospective review of case notes between Jan 1999 and March 2010 Results The range of corneal dystrophies presenting varied from Meesmans, Map-Dot , Reis-Buckler, Posterior polymorphous corneal dystrophy, congenital hereditary endothelial dystrophy, Granular and Lattice -Granular and the newly described x linked endothelial corneal dystrophy. The youngest child to present with symptoms was 14 months old. Management approach depended on the ultimate goal of allowing normal visual developemnt until the age of 8 years. Amblyopia plays a great role in the eventual visual outcome in children with corneal transplant surgery also riddled with difficulties in young children. Conclusion The classical descriptions of corneal dystrophies are not how they present in children . Certain symptoms and signs may tip the clinician off to the possibility of a corneal dystrophy. Visual rehabilitation in children is time limited and must be the priority for the treating physician. [source]

O-12 BLAND DYSKARYOSIS: A NEW PITFALL IN THINPREP® LIQUID BASED CYTOLOGY

CYTOPATHOLOGY, Issue 2006
M. A. Lynch
Liquid based cytology (LBC) has improved cell visualization and preservation in cervical cytology. There has been a reduction in inadequate rate and some data to suggest an increase in sensitivity for dyskaryosis. Training for LBC has focused on differences in distribution of abnormal cells, but in most cases the morphological appearance of the dyskaryotic cells themselves is similar to that seen in conventional cytology. We are describing a new presentation of dyskaryosis which may be a cause of false negative cytology. We have referred to this as ,Bland dyskaryosis' because cells appear deceptively bland on low power examination, and can be misinterpreted as metaplastic or endocervical cells. Bland dyskaryosis cells are seen in groups. The architecture of the group is very disorganized, and adjacent cells show variation in size. Cells have a high nuclear/cytoplasmic ratio and smooth nuclear membranes. Chromatin is finely granular and evenly distributed. This is an unusual presentation of high-grade dyskaryosis and we feel that there is a learning curve in laboratories converting to liquid based cytology. The spectrum of appearances of squamous dyskaryosis needs to be delineated to allow further increases in sensitivity for dyskaryosis. [source]

Nodular fasciitis of parotid region: A pitfall in the diagnosis of pleomorphic adenomas on fine-needle aspiration cytology

DIAGNOSTIC CYTOPATHOLOGY, Issue 3 2005
Ph.D., Reda S. Saad M.D.
Abstract Fine-needle aspiration cytology (FNAC) is routinely employed for the preoperative diagnosis of salivary gland lesions. Although most cases show morphologic features characteristic of specific entities, some lesions can be diagnostically challenging. We report two parotid aspirates, initially diagnosed as pleomorphic adenoma on FNA. The patients, a 33-yr-old white man, and a 24-yr-old white woman, presented with indurated lesions arising in the parotid gland region. The aspirates from both patients were markedly hypercellular. Smears showed a mixture of spindle cells with a well-demarcated cytoplasm showing occasional long cytoplasmic process; and cells with abundant cytoplasm with round to oval eccentric nuclei, giving the impression of plasmacytoid cells of pleomorphic adenoma. The nuclear chromatin was evenly distributed and finely granular with one or two occasional small nucleoli. Intermingled with the tumor cells were scattered neutrophils, eosinophils, and macrophages. Aggregates of spindle cells were also seen embedded in a mucoid background with occasional small tufts of a fibrillar mucoid stroma. These fibrillar tufts were magenta red in the Diff-Quik stain, giving the impression of matrix of pleomorphic adenoma. Both cases were later diagnosed on histologic examination as nodular fasciitis. Nodular fasciitis should be considered in the differential diagnosis of a mass arising in association with the parotid gland. Diagn. Cytopathol. 2005;33:191,194. © 2005 Wiley-Liss, Inc. [source]

Response of bobwhite quail and gray-tailed voles to granular and flowable diazinon applications

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2001
Guiming Wang
Abstract We used gray-tailed voles (Microtus canicaudus) and northern bobwhite quail (Colinus virginianus) as experimental model species to field test whether small mammals and birds respond differently to equivalent concentrations of a pesticide applied in granular and flowable formulations. In mid-May 1998, we placed voles into 15, 0.2-ha enclosures planted with a mixture of pasture grasses. In mid-July, we placed quail into the same enclosures with the voles. In late July, we applied the organophosphorus insecticide diazinon in five treatments; a control (all habitats sprayed with water), liquid formulation of diazinon at 0.55 kg/ha, liquid formulation of diazinon at 1.11 kg/ha, broadcast of granular diazinon at 1.11 kg/ha, and broadcast of granular diazinon at 2.22 kg/ha. The diazinon treatment in liquid and granular formulations did not depress population size or growth rate, or survival rate of voles. We found a significant difference in the survival rate of the quail between the controls and treatments; granular diazinon caused a measurable decline of quail survival, whereas the liquid application at an equivalent rate did not significantly affect quail survival. Analysis of our results suggests that ground-feeding birds are more susceptible to granular insecticides than flowable applications, but voles were not susceptible to either formulation at the rate we used. [source]

Area-Specific Resonance of Excitatory Networks in Neocortex: Control by Outward Currents

EPILEPSIA, Issue 8 2007
Manuel A. Castro-Alamancos
Summary:, During disinhibition or low [Mg++]o buffer, 7,14 Hz (,10 Hz) oscillations are generated by excitatory networks of interconnected pyramidal cells in motor (agranular) cortex but are absent in barrel (granular) cortex. Here we studied if the inability of barrel cortex to produce ,10 Hz oscillations during these conditions is because barrel cortex networks lack the necessary cellular mechanisms or, alternatively, because those mechanisms are inhibited by outward currents. The results show that blockers of slowly inactivating voltage-dependent K+ currents unmask ,10 Hz oscillations in barrel cortex, and this occurs in unison with the unmasking of intrinsic inward Ca++ currents that are kept suppressed by the outward currents. Moreover, the ,10 Hz oscillations unmasked in barrel cortex occur independently in upper and lower layers indicating that the ,10 Hz oscillation mechanisms are kept suppressed in multiple networks. The results reveal that the propensity of distinct excitatory networks of neocortex to generate epileptiform oscillatory activities is controlled by outward currents. [source]

Nerve growth factor ,/pro-nerve growth factor and their receptors in normal human oral mucosa

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2007
Katsuhiko Hayashi
Nerve growth factor , (NGF- ,) and its precursor proNGF are important for the differentiation and survival of neurons and dermal keratinocytes. The aim of this study was to determine the role that NGF might play in the differentiation and wound healing of oral mucosa. Cultured normal human oral mucosal keratinocytes expressed mRNA for NGF- ,/proNGF and for their receptors TrkA and p75NTR. Lysates from cultured oral mucosal keratinocytes did not contain detectable amounts of mature 14-kDa NGF- , but did contain several NGF proforms with molecular weights between 32 and 114 kDa. Culture medium from oral mucosal keratinocytes contained 75 kDa proNGF. The addition of NGF- , significantly enhanced the proliferation of oral mucosal keratinocyte cultures and in vitro scratch closure. Immunostaining of biopsies from normal oral mucosa showed the presence of proNGF in all epithelial layers. NGF staining was observed in the granular and upper spinous cell layers. TrkA immunoreactivity was detected in basal and parabasal cells, with weak to moderate staining in spinous and granular cell layers. p75NTR staining was seen in basal cell layers. These findings indicate that NGF- ,/proNGF have mitogenic and motogenic effects on oral mucosal keratinocytes and therefore may aid in the healing of oral wounds. Differential expression of NGF and NGF receptors throughout the epithelium suggests a role in epithelial differentiation. [source]

Micromorphology of soils derived from volcanic ash in Europe: a review and synthesis

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 2007
G. Stoops
Summary An analysis of the available literature on European volcanic ash soils has been made. Most has been published in Congress proceedings and Journals of national societies, less than half in English. More than half of the papers deal with soils on the Canary Islands. Many papers focus only on one aspect, and complete descriptions are found only in recent publications. Often the use of vague micromorphological terminology and the absence of analytical data make interpretation and comparisons difficult or impossible. Nonetheless, some general features do emerge. In the least-weathered soils, the micromass forms first coatings around the coarse constituents, later granules, finally giving rise to a loose granular microstructure in the topsoil, and a compacted granular one in the Bw horizons of typic andic materials. The b-fabric of the micromass is undifferentiated. With increasing weathering, clay coatings appear, the microstructure becomes more blocky and the b-fabric becomes speckled or even striated. In Vertisols and Aridisols, micromorphological characteristics are not much different from those in the comparable non-volcanic soils, except generally for the tendency to granular (intrapedal) microstructures. In Icelandic soils, microstratification, lenticular microstructure and preservation of plant residues as a result of cryic conditions and permanent volcanic and aeolian activity are observed. Weathering of volcanic glass in well-drained conditions yields allophane alteromorphs similar to palagonite, which are easily subject to fragmentation by pedoturbation. The possible influence of surface transport and burial on the formation of Bw-horizons in andic materials is discussed. [source]

Water-repellent soil and its relationship to granularity, surface roughness and hydrophobicity: a materials science view

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2005
G. McHale
Summary Considerable soil water repellency has been observed at a wide range of locations worldwide. The soil exhibiting water repellency is found within the upper part of the soil profile. The reduced rate of water infiltration into these soils leads to severe runoff erosion, and reduction of plant growth. Soil water repellency is promoted by drying of soil, and can be induced by fire or intense heating of soil containing hydrophobic organic matter. Recent studies outside soil science have shown how enhancement of the natural water repellency of materials, both porous and granular, by surface texture (i.e. surface roughness, pattern and morphology) into super-hydrophobicity is possible. The similarities between these super-hydrophobic materials and observed properties of water-repellent soil are discussed from a non-soil scientist, materials-based perspective. A simple model is developed for a hydrophobic granular surface and it is shown that this can provide a mechanism for enhancement of soil water repellency through the relative size and spacing of grains and pores. The model provides a possible explanation for why soil water repellency should be more prevalent under dry conditions than wet. Consequences for water runoff, raindrop splash and soil erosion are discussed. [source]

Ex-situ Formation Periodic Interlayer Structure to Improve Significantly the Impact Damage Resistance of Carbon Laminates

ADVANCED ENGINEERING MATERIALS, Issue 10 2003
X.-S. Yi
A periodically interleaved carbon laminate system, wherein solid thermoplastic thin layers are interleaved into each carbon ply, has been fabricated by means of an "ex-situ" type synthesis in which the thermoset and thermoplastic components are separated and interact only at elevated temperature. The Figure shows the boundary area between the two-phase granular and a pure epoxy-resin structure within a single carbon ply. [source]

Abiotic,biotic controls on the origin and development of spicular sinter: in situ growth experiments, Champagne Pool, Waiotapu, New Zealand

GEOBIOLOGY, Issue 2 2005
K. M. HANDLEY
Abiotic,biotic mechanisms of microstromatolitic spicular sinter (geyseritic) initiation and development were elucidated by in situ growth experiments at Champagne Pool (75 °C, pH 5.5). Siliceous sinter formed subaerially on glass slides placed along the margin of the hot spring. Environment,silica,microbe interactions were revealed by periodic collections of incremental sinter growth that formed under a range of environmental conditions including quiescence vs. wave turbulence, and wind,evaporation vs. steam,condensation. Sinter surfaces were intermittently colonized by voluminous networks of filamentous micro-organisms, with submicron diameters, that provided an extensive surface area for silica deposition. The subaerial distribution of sinter and its textures reflected micron- to centimetre-scale differences in environmental conditions, particularly relating to the balance between wave-supplied dissolved silica and its precipitation, forced by cooling and evaporation. A continuum of sinter textures formed, representing rates of silica precipitation that either out-paced biofilm growth or regulated the structural development of biofilms, and hence also the nature of microbially templated sinter. Massive laminae of porous, filamentous-network sinter and/or fenestrae (up to 10's of microns in thickness and diameter) formed at relatively low rates of silica deposition (approximately 0.2 mg slide,1 day,1). At high rates (>1.9 mg slide,1 day,1), densely packed, granular or nonporous sinter formed, with filament networks disappearing into the siliceous matrix and becoming imperceptible under scanning electron microscopy (SEM). Furthermore, spicules were nucleated by filamentous microcolonies, where their discrete conical morphologies were preserved by accretion of thin sinter laminae. Microstromatolitic spicular growth ensued at fluctuating low to high rates of silica precipitation. Greater apical sinter build-up, and hence upward polarity, resulted from focused microbial recolonization and progressively greater subaerial exposure at microspicule tips. The biogenic origin of spicular sinter at Champagne Pool clearly demonstrates that micron-scale biofilms, displaying self-organization patterns common to both biofilms and microbial mats, can be an essential factor in shaping characteristic centimetre-scale sinter macrostructures. These findings suggest that a biogenic origin for geyserites elsewhere should also be considered. Moreover, results corroborate the supposition that microbially generated surface roughness may be significant for stromatolite morphogenesis in cryptic Precambrian carbonates. [source]

Distribution and morphology of serotonin-immunoreactive axons in the hippocampal region of the New Zealand white rabbit.

HIPPOCAMPUS, Issue 1 2003

Abstract This study provides a detailed light microscopic description of the morphology and distribution of immunohistochemically stained serotonergic axons in the hippocampal region of the New Zealand white rabbit. The serotonergic axons were segregated morphologically into three types: beaded fibers, fine fibers, and stem-axons, respectively. Beaded fibers were thin serotonergic axons with large varicosities, whereas thin axons with small fusiform or granular varicosities were called fine fibers. Finally, thick straight non-varicose axons were called stem-axons. Beaded fibers often formed large conglomerates with numerous boutons (pericellular arrays) in close apposition to the cell-rich layers in the hippocampal region, e.g., the granular and hilar cell layers of the dentate area and the pyramidal cell layer ventrally in CA3. The pericellular arrays in these layers were often encountered in relation to small calbindin-D28K -positive cells, as shown by immunohistochemical double staining for serotonin and calbindin-D28K. The beaded and fine serotonergic fibers displayed a specific innervation pattern in the hippocampal region and were encountered predominantly within the terminal field of the perforant path, e.g., the stratum moleculare hippocampi and the outer two-thirds of the dentate molecular layer. These fibers were also frequently seen in the deep part of the stratum oriens and the alveus, forming a dense plexus in relation to large multipolar calbindin-D28K -positive cells and their basal extensions. Stem-axons were primarily seen in the fimbria and alveus. This innervation pattern was present throughout the entire hippocampal formation, but there were considerable septotemporal differences in the density of the serotonergic innervation. A high density of innervation prevailed in the ventral/temporal part of the hippocampal formation, whereas the dorsal/septal part received only a moderate to weak serotonergic innervation. These results suggest that the serotonergic system could modulate the internal hippocampal circuitry by way of its innervation in the terminal field of the perforant path, the hilus fasciae dentatae, and ventrally in the zone closely apposed to the mossy fiber layer and the pyramidal cells of CA3. This modulation could be of a dual nature, mediated directly by single serotonergic fibers traversing the hippocampal layers or indirectly by the pericellular arrays and their close relation to the calbindin-D28K -positive cells. The marked septotemporal differences in innervation density point toward a difference between the ventral and dorsal parts of the hippocampal formation with respect to serotonergic function and need for serotonergic modulation. Hippocampus 2003;13:21,37. © 2003 Wiley-Liss, Inc. [source]

Pseudoepitheliomatous hyperplasia , an unusual reaction following tattoo: report of a case and review of the literature

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 7 2007
Wei Cui MD
A 59-year-old woman presented with an itchy and uncomfortable raised lesion at a tattoo site (Fig. 1) on the lateral aspect of the left leg, just above the ankle. The tattoo had been placed 2 years before her presentation and the tattoo site was sun exposed. Immediately after she had the tattoo, she noticed redness of the skin. After a week, a pruritic and red scaly nodule developed that continued to gradually enlarge until her presentation. The patient had tried topical vitamin A and D ointment with no relief. The patient also had tattoos on the arms without any noticeable skin changes. The patient reported that the tattoo procedure on her leg was more painful than that on her arms, and was performed by a different (and perhaps inexperienced) tattoo artist. The original tattoo contained red, green, and yellow pigments. Figure 1. Raised nodular lesion with irregular margins A diagnosis of tattoo granuloma was considered; squamous cell carcinoma and fungal infection were included in the differential diagnosis. A punch biopsy was performed, followed by complete surgical excision of the lesion with a split-thickness skin graft from the right thigh. The skin excision specimen showed a 3 × 2.5-cm granular and pitted pink lesion with well-demarcated, somewhat irregular borders. The lesion was raised 0.5 cm above the skin surface. The lesion was present in the center of the original tattoo. Portions of the original tattoo with green and blue,green pigmentation were visible on either side of the lesion. No satellite lesions were identified. Microscopically, the raised lesion demonstrated striking pseudoepitheliomatous hyperplasia, with irregular acanthosis of the epidermis and follicular infundibula, hyperkeratosis, and parakeratosis (Fig. 2). Follicular plugging was present with keratin-filled cystic spaces. There was a brisk mononuclear inflammatory infiltrate in the dermis, composed primarily of lymphocytes, with admixed plasma cells and histiocytes. Giant cells were occasionally identified. Dermal pigment deposition was noted both within the lesion and in the surrounding skin, corresponding to the original tattoo. Variable dermal fibrosis was noted, with thick collagen bundles in some areas. There was no evidence of epidermal keratinocytic atypia, dyskeratosis, or increased suprabasal mitotic activity. Special stains (periodic acid,Schiff and acid-fast) for microorganisms were negative. Figure 2. (a) Raised lesion with marked pseudoepitheliomatous hyperplasia and follicular plugging (hematoxylin and eosin; magnification, ×2.5). (b) Irregularly elongated and thickened rete pegs with blunt ends associated with dermal chronic inflammation (hematoxylin and eosin; magnification, ×5). (c) Follicular dilation and plugging with keratin-filled cystic spaces (hematoxylin and eosin; magnification, ×5). (d) Dermal pigment and fibrosis (hematoxylin and eosin; magnification, ×10) [source]

Study on bulk polymerization of methyl methacrylate initiated by low intensity ultrasonic irradiation

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010
Sude Ma
Abstract Methyl methacrylate (MMA) was polymerized in bulk solutions using low intensity ultrasonic radiation of 0.25 W/cm2. The polymerization occurred after 1 h of irradiation time was applied. The polymerization rate was greatly accelerated either by increasing the amount of poly (methyl methacrylate) (PMMA) granular added into the system or by elongating the irradiation time. However, it was found that the reaction rate increased with the decreasing of the ultrasonic frequencies when the exposure time of the polymerization under the irradiation was less than 3 h. Experimental results verified that the polymerization was initiated by free radicals, which were mainly generated from the degradation of PMMA macromolecular chains, the friction between the polymer macromolecular chains and the solvent monomer. These findings were obviously different from those obtained when high intensity ultrasonic irradiation was used. The polymers fabricated in this study by using ultrasound irradiation have a narrower molecular weight distribution compared to those obtained from the polymerizations induced by the conventional initiators. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]

Determination of cut-off titers and agreement between immunofluorescence and immunoblotting methods for detecting antinuclear antibodies in children

JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2010
G. Aksu
Abstract Detection of antinuclear antibodies (ANA) is a diagnostic adjunct in patients with suspected autoimmune connective tissue diseases, and various detection methods are in use. The aim of this study was to analyze the agreement between the ANA immunoflourescence (IF) and immunoblotting (IB) methods and determine cut-off for children subjects in a laboratory setting. We evaluated 729 serum samples that were analyzed by both ANA IF and IB. The results were evaluated by ,2 test and, for agreement, , index was used. Frequencies determined for both 1:40,1:100 cut-off titers of ANA IF in relation to IB testing supported the idea that 1:100 starting dilution should be recommended in children subjects for ANA IF method and antigen specific immunoblot testing was needed, especially for some of the ANA IF negative samples. Agreement between the two methods, especially with homogenous, granular, and nucleolar ANA IF patterns, was statistically significant. J. Clin. Lab. Anal. 24:230,236, 2010. © 2010 Wiley-Liss, Inc. [source]

Immunohistochemical localization of ornithine decarboxylase in skin tumors

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 7 2000
Masayori Kagoura
Background: Ornithine decarboxylase (ODC) plays an important role in the biosynthesis of polyamines. Induction of ODC and polyamine synthesis has been demonstrated in neoplastic tumors and is thought to be related to the degree of malignancy. Methods: In this study, we investigated a series of basal cell epitheliomas (BCE), Bowen's disease, squamous cell carcinomas (SCC), and metastatic tumors of the skin using an antibody against ODC for immunohistochemistry. Results: Eight of 12 cases of BCE failed to show a positive reaction for ODC. In Bowen's disease, 5 of 13 cases diffusely showed positive reaction for ODC. Fourteen of 15 cases of SCC showed ODC expression, the intensity of which was decreased in the peripheral layer. At higher magnification, the distribution of ODC in the positive SCC cases showed granular and heterogenous patterns. Ten of 14 cases of metastatic skin tumors exhibited positive reactions, and well-differentiated adenocarcinomas tended to show more strongly positive than poorly-differentiated ones. Conclusions: These results support the conclusion that the intensity and the incidence of positive immunohistochemical staining for ODC correlate with the degree of cellular differentiation, and furthermore, that heterogenous distribution of ODC staining may be associated with heterogeneity of tumor cells. [source]

Density segregation in vibrated granular beds with bumpy surfaces

AICHE JOURNAL, Issue 10 2010
Eldin Wee Chuan Lim
Abstract Segregation of granular materials by virtue of density or size is a commonly encountered phenomenon in nature. Despite its widespread interest among many researchers in recent years, a complete and unified understanding of granular segregation remains elusive to date. Using molecular dynamics simulations, we report a novel technique of inducing density segregation in a binary mixture of granular materials subjected to vibrations by the use of a bumpy vibrating base. Density segregation in the vertical directions may be induced by oscillating the bumpy base composed of discrete solid particles vertically or horizontally. In both cases, lighter particles tended to rise to the top of the granular bed and form a layer above the heavier particles. We suggest that differences in granular temperature profiles arising from the two different modes of vibrations may play an important role in determining the extent of density segregation occurring in binary granular mixtures. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source]

Molecular characterization of mitocalcin, a novel mitochondrial Ca2+ -binding protein with EF-hand and coiled-coil domains

JOURNAL OF NEUROCHEMISTRY, Issue 1 2006
Mitsutoshi Tominaga
Abstract Here we have identified and characterized a novel mitochondrial Ca2+ -binding protein, mitocalcin. Western blot analysis demonstrated that mitocalcin was widely expressed in mouse tissues. The expression in brain was increased during post-natal to adult development. Further analyses were carried out in newly established neural cell lines. The protein was expressed specifically in neurons but not in glial cells. Double-labeling studies revealed that mitocalcin was colocalized with mitochondria in neurons differentiated from 2Y-3t cells. In addition, mitocalcin was enriched in the mitochondrial fraction purified from the cells. Immunohistochemical studies on mouse cerebellum revealed that the expression pattern of mitocalcin in glomeruli of the internal granular and molecular layers was well overlapped by the distribution pattern of mitochondria. Immunogold electron microscopy showed that mitocalcin was associated with mitochondrial inner membrane. Overexpression of mitocalcin in 2Y-3t cells resulted in neurite extension. Inhibition of the expression in 2Y-3t cells caused suppression of neurite outgrowth and then cell death. These findings suggest that mitocalcin may play roles in neuronal differentiation and function through the control of mitochondrial function. [source]

Regulation of SVZ-derived gliogenesis by inflammatory-demyelination

JOURNAL OF NEUROCHEMISTRY, Issue 2002
A. Baron-Van Evercooren
Identifying a source of cells with the capacity to generate oligodendrocytes in the adult CNS would help the development of strategies to promote myelin repair. During development of the neonate rodent forebrain, most oligodendrocytes derive from the subventricular zone (SVZ), a germinative area which also contributes to the genesis of astrocytes and neurons. While the SVZ persists in the adult brain, its size is largely reduced and its contribution to cell genesis is essentially restricted to the renewal of the granular and periglomerular neurons of the olfactory bulb. Lesion derived signals can have a profound impact on the behavior of the SVZ cells. While cortical trauma triggers their mobilization and differentiation in astrocytes in the lesioned cortex (Holmin et al. 1997), focaly-induced demyelination promotes their migration in the demyelinated white matter and differentiation in astrocytes and oligodendrocytes (Nait-Oumesmar et al. 1999). Using EAE, we will show that multifocal demyelination (i) promotes the proliferation of the SVZ precursors (ii) enhances their migration towards the olfactory bulb and triggers their mobilization to multiple sites of the diseased white matter, and (iii) induces their differentiation in neurons, astrocytes and oligodendrocytes in the olfactory bulb, and in oligodendrocytes and astrocytes in the demyelinated white matter. SVZ precursors could thus be a source of oligodendrocytes and contribute with oligodendrocyte progenitors to the replacement of lost oligodendrocytes in demyelinating diseases of the adult CNS. [source]

Characterization of granular flow of wet solids in a bladed mixer

AICHE JOURNAL, Issue 8 2006
Azzeddine Lekhal
Abstract In this study, we measure instantaneous, average, and fluctuating velocity fields at exposed surfaces for dry and wet grains in a vertical cylindrical mixer, agitated by four pitched blades. When the material is dry, the free surface of the granular bed deforms, rising where the blades are present, and falling between blade passes. Although average velocities are predominantly azimuthal, instantaneous velocities tracked in time reveal three-dimensional particle circulations, including significant periods of particle motion in the opposite direction to that of the blades, indicative of bed penetration. When moisture is added to the solid particles, the flow dynamics change from a regime dominated by the motion of individual grains to a regime controlled by the motion of small clumps that form as a result of the cohesive forces. This transition is characterized by a reduced particle,particle collision frequency and exhibits a sharp decrease in the granular temperature at the free surface. This transition is also characterized by an increase in bed porosity, which is attributed to increased cohesiveness arising from liquid bridges. A Fourier transform analysis conducted on the tangential component of the velocities (dominant flow) shows that a group of high frequencies exceeding the blade rotation frequency become significant with added moisture. These are characteristics of the large number of wet agglomerates flowing between successive blade passes. © 2006 American Institute of Chemical Engineers AIChE J, 2006 [source]

Coupled axial,radial segregation in rotating drums with high fill levels

AICHE JOURNAL, Issue 7 2006
H. P. Kuo
Axial segregation and radial segregation within the granular bed in a rotating drum with a fill level > 50% were experimentally investigated. The axial segregated patterns and the radial segregated patterns were coupled within the bed, resulting in observation of new segregated patterns at the plane along the rotational shaft. The segregated patterns are different from the previous axial band and radial core patterns and show coupled new patterns, including the "cross" patterns, the "band-core-in-core" patterns, and other geometric patterns. The new segregation patterns are strong functions of the fill level and the rotational speed of the drum. The formation of the axial,radial coupled patterns was attributed to the fill level, the free flowing surface of the bed. A virtual drum hypothesis is proposed to explain the formation of the complex segregated patterns. © 2006 American Institute of Chemical Engineers AIChE J, 2006 [source]

Expression of human ,-defensins-1 and -2 peptides in unresolved chronic periodontitis

JOURNAL OF PERIODONTAL RESEARCH, Issue 4 2004
Qian Lu
Background:, Human ,-defensins (hBDs) are antimicrobial peptides which contribute to host innate immunity by disrupting the membrane integrity of a broad spectrum of microorganisms. Objectives:, This study aimed to determine the expression profiles of hBD-1 and -2 peptides in gingiva and to assess the possible relations of these antimicrobial peptides with periodontal health and disease. Methods:, Seven periodontally healthy subjects and 22 patients with unresolved chronic periodontitis were recruited and the gingival biopsies collected consisted of healthy tissues from the healthy subjects (HT-C); periodontal pocket tissues (PoT) and inflamed connective tissues (ICT) from the base of pocket, i.e. granulation tissues, as well as clinically healthy tissues (HT-P) from the adjacent clinically healthy sites from the patients. The expression of hBD-1 and -2 peptides was detected by immunohistochemistry and quantitatively analyzed with a computerized image processing system. Results:, Both hBD-1 and -2 peptides were detected in all periodontally healthy subjects, while hBD-1 was detected in all patients and hBD-2 was found in most of the patients. Their expression was mainly confined to the granular and spinous layers of gingival epithelium, in which hBD-1 was detected in both intercellular spaces and cytoplasm, whereas hBD-2 was mainly observed in the cytoplasm. HT-C expressed significantly higher levels of hBD-2 than HT-P (p < 0.05). Within the patients, both defensins were up-regulated significantly in PoT as compared with the adjacent HT-P (p < 0.05). Conclusions:, The present study showed that hBD-1 and -2 were frequently expressed in the granular and spinous layers of gingival epithelia and their expression may be associated with periodontal health and disease. [source]

Novel Fabrication of Ca-Doped LaNbO4 Thin-Film Proton-Conducting Fuel Cells by Pulsed Laser Deposition

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 7 2010
Anna Magrasó
Thin films of 0.5% Ca-doped La0.995Ca0.005NbO4,, (LCNO) proton-conducting electrolytes of ,2 ,m thickness were obtained by pulsed laser deposition on NiO,LaNbO4 composite substrates. The morphology of the films was granular after annealing at T,1000°C and evolved to spherical-like grains at 1100°C and above. The structure and composition of the films were characterized by X-ray diffraction and X-ray photoelectron spectrocopy. LCNO films showed the monoclinic fergusonite-type structure at room temperature. The area-specific resistance for a ,2-,m-thick electrolyte was in the order of 0.4 ,·cm2 at 600°C based on estimates of the electrode area. Temperature dependency of the electrical conductivity at 600°,700°C was comparable with that of bulk disks of the material. [source]

Circumscribed palmar hypokeratosis: clinical evolution and ultrastructural study after prolonged treatment with topical calcipotriol

JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 4 2005
F Urbina
Abstract Circumscribed palmar hypokeratosis is a recently described condition that consists of a solitary area of depressed skin affecting the palm (or sole). Its histopathological features include a thinned horny layer, a slightly diminished granular cell layer, and intraepidermal vacuolated cells. Prolonged treatment with topical calcipotriol resulted in complete recovery of the affected zone in the case reported here. A second biopsy of the lesion taken at around the fourth year of therapy showed a normalization of the granular layer, a reduction in the intraepidermal vacuolated cells, and a somewhat thicker horny layer. An ultrastructural study carried out at the same time showed a reduction in keratin bundles and keratohyalin granules, and an increase in lipid droplets up to the horny layer. These findings and the therapeutic response to topical calcipotriol support the concept that circumscribed palmar hypokeratosis is a focalized abnormal keratinization defect morphologically expressed at the granular and horny layers. [source]

Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 83

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003
G Lauria
We describe a 64-year-old patient complaining of progressive gait disturbance, referred to the compressive effect of multiple discal protrusions, for about 3 years. At the age of 62 he presented epileptic seizures during a febrile episode. Cerebral MRI showed bilateral frontobasal T2-weighted hyperintensity involving cortex and white matter. Partial seizures reappeared one year later and a MRI revealed a mild frontobasal atrophy. At the moment of our observation, neurological examination showed waddling gait with bilateral foot drop, muscular atrophy and weakness limited to the gluteal muscles and widespread deep tendon areflexia. Nerve conduction studies showed absent F-waves at both upper and lower limb examination, with normal distal sensorimotor nerve conduction. Needle EMG examination detected mild chronic partial denervation, predominant in proximal muscles of lower limbs. Somatosensory evoked potentials recorded from upper extremities showed bilateral increase in early latencies (N9). Overall, neurophysiological findings indicated a widespread radiculopathy. Serum exams revealed positive anti-nucleus (1:640, granular). CSF examination detected increased IgG level and several oligoclonal bands. Chest radiogram was normal. Soon after our first observation, the patient showed symptoms of respiratory insufficiency. A CT scans revealed a thoracic mass compatible with microcytoma, whereas anti-Hu (3 +) antibodies and increased NSE (neuronal specific enolase) titer were found. In the following two weeks, the patient showed a progressive worsening of the general clinical conditions and died. We interpreted this complex neurological picture, which included an atypical limbic encephalitis and a slowly progressive polyradiculopathy, as a paraneoplastic syndrome. The almost complete resolution of the encephalitic process and the subtle chronic involvement of the peripheral nervous system, characterized by a limited, though widespread, radicular impairment, are rather peculiar features. [source]

Meningeal alveolar soft part sarcoma confirmed by characteristic ASPCR1-TFE3 fusion

NEUROPATHOLOGY, Issue 4 2009
Istvan Bodi
Sarcoma metastatic to the brain is uncommon and rarely occurs as the initial manifestation of tumor. Alveolar soft part sarcoma (ASPS) is a rare but well-studied subtype of sarcoma. A 39-year-old man presented with seizures due to a left temporal meningeal-enhancing lesion with striking brain edema on MRI. The patient underwent neurosurgical resection for suspected meningioma. Histology showed large tumor cells clustering and forming small nests, in places with pseudoalveolar pattern. Diastase-resistant periodic acid-Schiff revealed very rare granular and rod-like cytoplasmic inclusions. Immunohistochemistry showed convincing positivity only with vimentin and smooth muscle actin. The histological features were strongly suggestive of ASPS. At the molecular level RT-PCR and sequencing analysis demonstrated ASPCR1-TFE3 fusion confirming the histological diagnosis of ASPS. There was no evidence of primary extracranial tumor by physical examination and on chest and abdominal CT scan 11 months after presentation. ASPS typically arise from the soft tissues of the extremities and develop multiple metastatic deposits usually with a long clinical course. This case may represent primary meningeal ASPS although metastatic deposit from an undiscovered primary site cannot be entirely excluded. [source]

No Role for Kaposi Sarcoma-Associated Herpesvirus in Pediatric Idiopathic Pulmonary Hypertension

PEDIATRIC PULMONOLOGY, Issue 2 2006
Csaba Galambos MD
Abstract Idiopathic pulmonary hypertension (IPHT) is a rare but progressive disease with devastating outcomes, especially in children. The etiology is unknown. A recent study reported a potential role of Kaposi sarcoma-associated herpesvirus in the pathogenesis of IPHT in adults. Our goal was to test if this association exists in pediatric patients. The pathology specimen database of the Children's Hospital of Pittsburgh from 1980,2004 was searched, and all patients with a diagnosis of IPHT were enrolled. Lung tissues containing the characteristic plexiform lesion from all patients were selected and stained with antibody to latent nuclear antigen (LNA-1) of Kaposi sarcoma-associated herpesvirus. To avoid false-negative results, three different positive controls were utilized. Eighteen patients were identified; 3 had familial pulmonary hypertension, and 2 had persistent pulmonary hypertension of infancy. Patients' ages varied from 3 days to 17 years, and the female-to-male ratio was 2:1. No positive history of HIV or of parents with HIV was identified. The Heath-Edwards grade of pulmonary hypertension was between 3,5. All patients died: 11 from the disease, and the remaining 7 died after receiving a lung transplant. Immunohistochemical staining with LNA-1 antibody showed no staining of either endothelial or smooth muscle cell nuclei in any of the patients' lung tissues, while all three positive control specimens showed the characteristic intranuclear granular, punctate staining pattern. Our results do not support a role for Kaposi sarcoma-associated herpesvirus in the pathogenesis of pediatric IPHT. Pediatr Pulmonol. © 2005 Wiley-Liss, Inc. [source]

Alternative Definitions of Micro,to,Macro Transitions in Particle Aggregates of Granular Materials

PROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2003
Joachim Dettmar Dipl.-Ing.
An alternative approach to the modelling of the overall macroscopic response of granular materials is presented based on micro,macro transitions. A homogenized macro,continuum is considered with locally attached granular microstructures. The new developments include a consistent transfer of micro,macro transitions from continuous to particle microstructures with a new overall macro,stress definition. Secondly, a new class of boundary conditions for displacements/ rotations on prescribed boundary,frame particles is presented that yields upper and lower bounds with regard to the aggregate stiffness. Thirdly, a unified implementation of the displacement/ rotation boundary constraints by a penalty method is developed that proves to be a convenient computational tool in explicit codes. [source]

Carbonatitic Volcanic Genesis of Hetaoqing Fe-Cu Deposit in Central Yunnan, China

RESOURCE GEOLOGY, Issue 4 2003
Yongbei Zhang
Abstract. The Kunyang rift on western margin of Yangtze Platform is a continental rift, and also a rare Precambrian Fe-Cu mineralization zone in China. The Wuding-Lufeng mineralization area in the middle section of the rift is an important part of the zone, and an elliptic-shaped volcanic collapsed basin, controlled by a ring fracture system with carbonatitic volcanic rocks mainly occurring along the northwestern edge of the basin. The Hetaoqing Fe-Cu ore deposit at the western side of the basin is hosted in carbonatitic volcanic rocks and pyroclastic sedimentary rocks. The original ore bodies occur as layers, bands and lenses conformable to the host carbonatitic rocks. The ores usually appear as massive, impregnated and granular in carbonatitic rocks, and as brecciform and sandy in pyroclastic sedimentary rocks. Ore-forming minerals are magnetite, hematite, chalcopy-rite, bornite, pyrite, carrollite, molybdenite, cobaltite and skinnerite, and secondary minerals limonite, chalcocite, azurite, malachite and tenorite. Gangue minerals are calcite, dolomite, ankerite, common hornblende, arfvedsonite, augite, aegirine-augite, albite, phlogopite, biotite, chlorite and apatite. Evidences of mineral chemistry, trace elements and isotopic ratios of ores, as well as geological features, suggest that the original ores are igneous in origin. Chemical features of magnetites in the deposit belong to carbonatite type, and are similar to those from the Bayan Obo carbonatites. The ores are rich in iron, titanium, rare earth elements, niobium, tantalum, gold, silver, phosphor and sulfur. These features indicate that the Fe-Cu deposit associated with volcanic activity in the Wuding-Lufeng basin is alkali-carbonatite volcanic type. [source]

Cold and hot gas filtration using a novel mobile granular bed with an inner fluidized section

THE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2002
Nicolas Abatzoglou
Abstract Two experimental studies were conducted with a novel moving granular bed filter (NMGBF). The first one was performed on a cold and dry mock-up module operated at room temperature and was aimed at a) proving the concept, b) establishing the operating patterns and flow profiles and c) optimizing the operating conditions. The gas flowrate and the geometry of the filter were the main variables studied. The second study was conducted on a prototype hot filter PDU (Process Development Unit) under real time operating conditions. The filter was one of the modules of a hot-gas-conditioning-train in a fluidized bed gasifier. Results showed similar particles collection efficiency for hot- and cold-dry filtration. The filter showed an efficiency of 99.9% over 55 h filtration time for particles larger than 1 ,m, while for submicronic particles the efficiency is between 84% and 96% (weight basis). This paper presents and discusses the apparatus, the experimental methods and conditions as well as characteristic results on the two prototypes used. Deux études expérimentales ont été menées à I'aide d'un nouveau filtre à lit granulaire mobile (NMGBF). La premiére a été menée sur une maquette froide et séche à la température ambiante et visait a (a) prouver le concept, (b) établir les modéles de fonctionnement et les profus d'écoulement et (c) optimiser les conditions opératoires. Les variables étudiées sont le débit de gaz et la géométrie du filtre La seconde étude a été menée sur une unite de développement de procédes prototype à filtre chaud dans des conditions opératoires en temps réel. Le filtre est un des modules du train de conditionnement à gaz chaud dans un gazéificateur à lit fluidise. Les résultats montrent une efficacite de collecte des particules comparable pour la filtration sèche chaude et froide. Le filtre montre une efficacité de 99,9 % pour un temps de filtration de 55 h avec des particules au-dessus de 1 ,m, alors qu'avec des particules inférieur au micron I'efficacite' se situe entre 84 et 96 % (sur la base massique). On décrit dans cet article I'appareil, les méthodes expérimentales et les conditions, ainsi que les résultats caractéristiques des deux prototypes utilisés. [source]

Characteristics of Filiform, Fungiform and Vallate Papillae and Surface of Interface Epithelium-Connective Tissue of the Maned Sloth Tongue Mucosa (Bradypus torquatus, Iliger, 1811): Light and Scanning Electron Microscopy Study

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2009
E. J. Benetti
Summary The study of lingual surfaces and the surface of interface epithelium-connective tissue of the tongue of Bradypus torquatus was performed by employing the light and scanning electron microscopy (SEM) techniques. The results revealed that the rostral part of the tongue presents a round apex and covered by filiform and fungiform lingual papillae and a ventral smooth surface. It was observed that the epithelial layer of the dorsal surface possesses the basal, spinosum, granular and cornified epithelial cells. The lamina propria is characterized by a dense connective tissue forming the long, short and round papillae. Numerous typical filiform papillae are located especially in the rostral part intermingled for few fungiform papillae, which were revealed in three-dimensional SEM images. Usually, the fungiform papillae are located in the border of rostral apex of the tongue exhibiting the rounded form. They are covered by keratinized epithelial cells. In the fungiform papillae, several taste pores were observed on the surface. The vallate papillae presented numerous taste buds in the wall of epithelial cells, being that the major number of taste buds is located on the superior half of vallate papilla. The taste pores are surrounded by several laminae of keratinized epithelial cells. The samples treated with NaOH solution and examined by SEM revealed, after removal of the epithelial layer, the dense connective core in original disposition, presenting different sizes and shapes. The specimens stained with Picrosirius and examined by polarized light microscopy revealed the connective tissue, indicating the collagen fibres type I and type III. [source]