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Inner Layer (inner + layer)
Selected AbstractsNanofibrous Patches for Spinal Cord RegenerationADVANCED FUNCTIONAL MATERIALS, Issue 9 2010Yiqian Zhu Abstract The difficulty in spinal cord regeneration is related to the inhibitory factors for axon growth and the lack of appropriate axon guidance in the lesion region. Here scaffolds are developed with aligned nanofibers for nerve guidance and drug delivery in the spinal cord. Blended polymers including poly(L -lactic acid) (PLLA) and poly(lactide- co -glycolide) (PLGA) are used to electrospin nanofibrous scaffolds with a two-layer structure: aligned nanofibers in the inner layer and random nanofibers in the outer layer. Rolipram, a small molecule that can enhance cAMP (cyclic adenosine monophosphate) activity in neurons and suppress inflammatory responses, is immobilized onto nanofibers. To test the therapeutic effects of nanofibrous scaffolds, the nanofibrous scaffolds loaded with rolipram are used to bridge the hemisection lesion in 8-week old athymic rats. The scaffolds with rolipram increase axon growth through the scaffolds and in the lesion, promote angiogenesis through the scaffold, and decrease the population of astrocytes and chondroitin sulfate proteoglycans in the lesion. Locomotor scale rating analysis shows that the scaffolds with rolipram significantly improved hindlimb function after 3 weeks. This study demonstrates that nanofibrous scaffolds offer a valuable platform for drug delivery for spinal cord regeneration. [source] Total upper lip reconstruction with a free temporal scalp flap: Long-term follow-up ,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 7 2003Kao-Ping Chang MD Abstract Background. In men, reconstruction of large full-thickness defects of the upper lip requires both an inner layer to replace the mucosal lining and an outer hair-bearing layer. Methods. When locating the superficial temporal vessels, the design of the temporal flap is marked following the hairline needed. After meticulously dissecting the flap, it is inset and microanastomosed with the facial blood vessels. The internal mucosal layer of the flap is grafted on. During the follow-up period, the sensory recovery and motor functions are examined and recorded. Results. The postoperative courses were uneventful, and patients were satisfied with the results. One patient has a long follow-up period of 18 years. Conclusions. The free temporal scalp hair-bearing flap offers a reasonable alternative to conventional techniques in the reconstruction of large defects of the male upper lip or even a total upper lip. It is a single-staged, relatively simple method of providing hair-bearing skin to the upper lip. © 2003 Wiley Periodicals, Inc. Head Neck 25: 602,605, 2003 [source] Two relatively distinct patterns of ameloblastoma: an anti-apoptotic proliferating site in the outer layer (periphery) and a pro-apoptotic differentiating site in the inner layer (centre)HISTOPATHOLOGY, Issue 1 2001F Sandra Two relatively distinct patterns of ameloblastoma: an anti-apoptotic proliferating site in the outer layer (periphery) and a pro-apoptotic differentiating site in the inner layer (centre) Aims:,This study was performed to determine the apoptotic behaviour of ameloblastomas by analysing the role of bcl-2 family proteins in ameloblastomas and the location of terminally apoptotic cells in the ameloblastoma epithelial tissues. Methods and results:,For immunohistochemistry, tissue sections of 32 patients were treated with an antigen-retrieval method. Primary antibodies against the apoptosis-related proteins, bcl-2, bcl-X, bax, and bak were applied. Besides immunohistochemistry, Western blotting and TUNEL were also performed. Most of the outer layer cells were predominantly stained by the bcl-2 antibody, while most of the inner layer cells were stained by antibodies against the apoptosis-modulating proteins, bax and bak. Among the bcl-2 family, bcl-2 was the most ubiquitously expressed protein in ameloblastomas, while bcl-X was expressed in the greatest concentrations. The major bcl-X protein was bcl-XL. Some of the inner layer cells entered the terminal apoptotic stage, which were revealed by TUNEL. The acanthomatous areas over-expressed the apoptosis-modulating proteins, especially bak. Conclusions:,Ameloblastoma has much more apoptosis-inhibiting protein than the apoptosis-modulating protein. Ameloblastoma has two relatively distinct patterns, an anti-apoptotic proliferating site in the outer layer (periphery) and a pro-apoptotic differentiating site in the inner layer (centre). The acanthomatous area, which was stained strongly by bak antibody and contained numerous terminally apoptotic cells, was considered as the differentiated area. [source] Evaluation of the integrity of aseptic packages containing various filling productsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2006Chuan-Liang Hsu Summary The objective of this study was to investigate the integrity of aseptic aluminium laminate packages for different filling products after form-fill-seal processing using various testing methods. The integrity of the package was found to be influenced by the physical properties of filling product. When soyamilk (watery) was the filling product, the measured currents were lower than 10 ,A for all of the packages subjected to electrolytic testing. If guava juice (high viscosity with high particulate content beverage) was the filling product, a total of 40% of tested packages showed escalation of current to greater than 1000 ,A. This poor integrity was found to have resulted from compromise of the inner layer of packaging because of the particulate content of the juice. It was also demonstrated that the damage to the inner lining of the packages did not lead to the deterioration of the filling product by causing the development of penetrating micro holes. The cyclic voltammetry method is applicable to distinguish whether penetrating micro holes and damage have occurred in the plastic inner layer of a package. [source] Electrospun polylactide/silk fibroin,gelatin composite tubular scaffolds for small-diameter tissue engineering blood vesselsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2009Shudong Wang Abstract Many synthetic scaffolds have been used as vascular substitutes for clinical use. However, many of these scaffolds may not show suitable properties when they are exposed to physiologic vascular environments, and they may fail eventually because of some unexpected conditions. Electrospinning technology offers the potential for controlling the composition, structure, and mechanical properties of scaffolds. In this study, a tubular scaffold (inner diameter = 4.5 mm) composed of a polylactide (PLA) fiber outside layer and a silk fibroin (SF),gelatin fiber inner layer (PLA/SF,gelatin) was fabricated by electrospinning. The morphological, biomechanical, and biological properties of the composite scaffold were examined. The PLA/SF,gelatin composite tubular scaffold possessed a porous structure; the porosity of the scaffold reached 82 ± 2%. The composite scaffold achieved the appropriate breaking strength (1.28 ± 0.21 MPa) and adequate pliability (elasticity up to 41.11 ± 2.17% strain) and possessed a fine suture retention strength (1.07 ± 0.07 N). The burst pressure of the composite scaffold was 111.4 ± 2.6 kPa, which was much higher than the native vessels. A mitochondrial metabolic assay and scanning electron microscopy observations indicated that both 3T3 mouse fibroblasts and human umbilical vein endothelial cells grew and proliferated well on the composite scaffold in vitro after they were cultured for some days. The PLA/SF,gelatin composite tubular scaffolds presented appropriate characteristics to be considered as candidate scaffolds for blood vessel tissue engineering. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] Reproductive biology of female big-bellied seahorsesJOURNAL OF FISH BIOLOGY, Issue 3 2004C. W. Poortenaar In this study, ovarian morphology, reproductive condition and sex steroid levels were investigated in the big-bellied seahorse Hippocampus abdominalis, collected by snorkel and SCUBA diving in Wellington Harbour, New Zealand. Within the ovary, oocytes were contained between an outer muscular wall and an inner layer of luminal epithelium. Two germinal ridges ran along the entire length of the ovary. In cross-section, oocytes were arranged in sequential order of development beginning at the germinal ridges and ending at the mature edge. Ovarian lamellae were absent. Vitellogenic and advanced cortical alveoli oocytes were elongated in shape, whereas maturing oocytes were distinctively pear-shaped. Mature oocytes were large (2·6 , 4·4 mm in length) and aligned with the animal pole towards the muscular wall. Reproductively mature females were found throughout the year indicating a protracted reproductive season. The gonado-somatic index was significantly different between all ovarian stages, but the hepato-somatic index was not. Females with previtellogenic ovaries had significantly higher plasma concentrations of testosterone than females with vitellogenic or maturing ovaries. There was no significant difference in plasma concentrations of testosterone between females with vitellogenic or maturing ovaries, or in plasma concentrations of 17,-oestradiol between females in all ovarian stages. This study contributes to the knowledge on the reproductive biology of female syngnathids. [source] Observations of Dermocystidium sp. infections in bullheads, Cottus gobio L., from a river in southern EnglandJOURNAL OF FISH DISEASES, Issue 4 2004S W Feist Abstract Bullheads, Cottus gobio, with macroscopic external cysts on the skin and fins measuring up to 3 mm in diameter were detected in the River Allen and its tributaries in southern England between 1992 and 1998. The prevalence of these cysts was up to 50% at some sites. Examination of cyst contents revealed the presence of numerous spores, typical of the genus Dermocystidium, measuring 8 ,m in diameter. The parasite developed within well-defined cysts, which were located in the hypodermal connective tissues of the host. No cysts were present on the fins of any of the fish examined. Histological examination revealed a cyst wall consisting of an inner layer of dense eosinophilic material similar to that reported for Dermocystidium spp. forming coenocytic hyphae. No evidence was found of systemic infection or hyphal formation. Spores contained a prominent refractile body, which gave a weakly positive reaction for polysaccharides with the periodic-acid Schiff reaction and was positively stained with acidic dyes. Several examples of ruptured cysts were seen in histological sections and in some of these cases the host epithelial layer was breached, allowing release of the spores to the environment. Morphological features of, and host response towards, the Dermocystidium sp. in bullheads are compared with similar infections in salmonids and other freshwater fish species. [source] Plagioclase replacement textures in partially eclogitised gabbros from the Sanddal mafic-ultramafic complex, Greenland CaledonidesJOURNAL OF METAMORPHIC GEOLOGY, Issue 5 2001H. M. Lang Abstract The Sanddal mafic-ultramafic complex (SMUK) is a cluster of variably eclogitised mafic and ultramafic bodies that comprise the westernmost known eclogite facies locality in the North-East Greenland eclogite province (NEGEP). Although there are no true eclogites in the SMUK, we interpret three distinct textural types of plagioclase replacement to record sequential stages in adjustment of SMUK olivine gabbro-norites to eclogite facies conditions. The earliest stage, in which plagioclase was replaced by omphacite/spinel symplectite before nucleation of garnet (Type 1A & 1B) has not previously been described. Documentation of this texture provides clear evidence that, at least in some cases, garnet nucleation is delayed relative to nucleation of omphacite and is a rate-limiting step for eclogitisation. Type 1C domains were produced by scattered nucleation of garnet in the same sample. In Type 2 domains, plagioclase was replaced by a layered corona with an outer layer of garnet, an inner layer of omphacite and an interior of inclusion-rich plagioclase. In Type 3 domains, the omphacite layer was overgrown by the garnet rim, and omphacite is preserved only as inclusions in garnet. In more coarse grained leucogabbros, recrystallization was more complete, plagioclase replacement textures were less localised, and could not be divided into distinct stages. Plagioclase replacement in SMUK samples was not isochemical, and required diffusion of at least Mg and Fe from replacement of mafic phases in the surroundings. Strong compositional gradients in garnet reflect disequilibrium and were controlled by the different diffusion rates of Mg/Fe and Ca, different local chemical environments, and progress of the plagioclase breakdown reaction. The presence of small amounts of hydrous minerals (amphibole, phlogopite and clinozoisite) in local equilibrium in plagioclase domains of most SMUK samples indicates that a small amount of H2O was present during high pressure metamorphism. [source] Investigation of hatching and early post-embryonic life of freshwater crayfish by in vitro culture, behavioral analysis, and light and electron microscopyJOURNAL OF MORPHOLOGY, Issue 7 2008Günter Vogt Abstract The late embryonic and early post-embryonic life period of freshwater crayfish, which is the main time period of organogenesis, is poorly investigated because of the protective brooding behavior of crayfish mothers. A combination of in vitro culture, behavioral observations, and microscopic investigations of organs involved in hatching, attachment, exploration of the environment, and searching and processing of food yielded deeper insights in this important period of life. Experiments were performed with the robust parthenogenetic marbled crayfish. The following results were obtained: (1) Marbled crayfish can be raised in simple in vitro systems from 80% embryonic development to juvenile Stage 4 with up to 100% survival; (2) Hatching is prepared by chemical weakening of the egg shell and completed by levering actions of the hatchling's appendages; (3) The telson thread, a safety line that keeps the hatchling secured to the mother, is formed by secretions from the telson and the detaching inner layer of the egg case; (4) Molting Stage-1 juveniles are secured by an anal thread that results from delayed molting of the hindgut; (5) Active attachment of the hatchlings to the maternal pleopods with their 1st pereiopods is achieved by an innate fixed action pattern; (6) In vitro, juveniles are motile from Stage 2 despite incomplete development of their balance controlling statocysts. Movement pattern and social behavior vary greatly among individuals; and (7) Feeding starts in Stage 3, when the mouthparts and the gastric mill are fully developed. Onset of feeding is innate and does not require maternal contributions. In vitro culture of the isogenic marbled crayfish is recommended for broader use in research because it enables not only time and stage-specific sampling but also precisely timed experimental manipulations. J. Morphol., 2008. © 2008 Wiley-Liss, Inc. [source] Investigation on steam oxidation behaviour of TP347H FG Part 1: Exposure at 256 barMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 7 2005J. Jianmin Abstract The stainless steel TP347H FG is a candidate material for the final stage tubing of superheater and reheater sections of ultra supercritical boilers operated at steam temperatures up to 620°C in the mild corrosion environments of coal-firing. A series of field tests has been conducted with the aforementioned steel in coal-fired boilers and this paper focuses on the steam oxidation behaviour for specimens tested at various metal temperatures for exposure times of 7700, 23000 and 30000 hours as investigated by light optical and scanning electron microscopy. The oxide present on the specimens is a duplex oxide, where the outer layer consists of two sub-layers, an iron oxide layer and an iron-nickel oxide layer; the inner layer is chromium rich chromium-iron-nickel oxide. Microstructure examination showed that for all these samples the varying grain size of subsurface metal affected the oxide thickness, where the larger the metal grain size, the thicker the oxidation scale. This gave the appearance of uneven inner oxides with a varying pit thickness. Comparison of the pit thickness measurement and oxide composition reveals that the oxidation rate is fast during the initial oxidation stage, but the subsequent growth of oxide from further exposure is slower due to the formation of a healing layer consisting of chromium rich oxide near original alloy grain boundaries. At a temperature region above 600°C a thin oxide rich in chromium and manganese is sometimes formed. In addition precipitation of secondary carbides in the bulk metal also occurs at this temperature region. [source] ON THE TUBE ULTRASTRUCTURE AND ORIGIN OF CALCIFICATION IN SABELLIDS (ANNELIDA, POLYCHAETA)PALAEONTOLOGY, Issue 2 2008OLEV VINN Abstract:, Tube ultrastructure of Jurassic and Cretaceous Glomerula is very similar to that of Recent Calcisabella, supporting the synonymy of these genera and the early Mesozoic origin of calcification in sabellids. Tube structure of serpulids differs from that of Glomerula; calcareous tubes probably evolved convergently within Sabellida. The tube wall in Recent Glomerula piloseta is composed of subparallel lamellae of aragonitic, irregular spherulitic prisms in the inner layer, and spherulites in the outer layer. Calcified lamellae are separated by organic films of different thickness. The structure of the internal tube layer in Glomerula piloseta, and the structure of entire wall in fossil Glomerula, are similar to the tube structure of Dodecaceria (Polychaeta, Cirratulidae). The irregular spherulitic prisms of Glomerula are similar to those found in the external layer of Hydroides dianthus and the internal layer of Spiraserpula caribensis. [source] NEW TUBE-BEARING ANTILLOCAPRINID RUDIST BIVALVES FROM THE MAASTRICHTIAN OF JAMAICAPALAEONTOLOGY, Issue 1 2006SIMON F. MITCHELL Abstract:, Two genera of tube-bearing antillocaprinid rudist bivalves from the Maastrichtian of Jamaica are recognised: Titanosarcolites Trechmann and Parasarcolites gen. nov. Titanosarcolites is recumbent, broadly equivalve and coils parallel to the myocardinal line, with tubes on the anteriodorsal, anterior, and anterioventral regions of the inner layer; there are two teeth and two teeth-like myophores in the left valve. Sockets for teeth have conical tabulae, those for myophores are filled with normal shell structure. A ligamental cavity is lacking. Parasarcolites is recumbent, with equal, subequal or moderately inequal valves, and the plane of coiling is at an angle of 34,63 degrees to the mediocardinal line. It has tubes in the dorsal and anterior-dorsal regions, and a myocardinal structure with blade like myophores, with the posterior tooth and socket strongly flattened. The position of the ligament is indicated by a comma-shaped cavity situated dorsalwards of the posterior tooth. Additional toothlets are present in the left valve. All sockets are filled with canal-bearing shell-structure. Five new species of Parasarcolites are described from the Upper Maastrichtian of Jamaica: Parasarcolites atkinsoni, P. baileyi, P. greeni, P. monotubularis and P. quadratus. [source] Lobular capillary hemangioma of the oral mucosa: Clinicopathological study of 43 cases with a special reference to immunohistochemical characterization of the vascular elementsPATHOLOGY INTERNATIONAL, Issue 1 2003Makoto Toida Clinical and histopathological features were investigated in 43 cases of oral lobular capillary hemangiomas (LCH) with a special reference to characteristics of the vascular elements. The lesions affected females more than males by a ratio of 1:1.5. Average age of the patients was 52.7 years. The lesions involved the gingiva (n = 15), the tongue (n = 13), the labial mucosa (n = 10) and other sites. The lesions appeared usually as a pedunculated mass with ulceration; size of the lesions was up to 15 mm. Histologically, a lobular area and an ulcerative area were distinguished. The density of vessels was about 1045/mm2 and 160/mm2 in the lobular and ulcerative areas, respectively. The average diameter of the vascular lumen was 9.1 5.6 mm (range: 2.8,42.0 mm) and 18.8 20.9 mm (range: 5.6,139.7 mm) in the lobular and ulcerative areas, respectively. In the lobular area, most of the vessels had an inner layer of endothelial cells showing positive reaction for von Willebrand factor (vWF) and CD34, as well as an outer layer of mesenchymal cells showing positive reaction for alpha-smooth muscle actin (ASMA). However, in the ulcerative area, there was a variety of types of vessels consisting of various proportions of both endothelial and ASMA-positive perivascular mesenchymal cells. These results indicate that most of the vascular elements in the lobular area resemble more pericapillary microvascular segments than they do capillaries. Thus, the authors propose the term ,lobular pericapillary hemangioma' to represent this type of lesion. [source] Proteomic analysis of spore wall proteins and identification of two spore wall proteins from Nosema bombycis (Microsporidia)PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 12 2008Zhengli Wu Abstract Microsporidia are fungal-like unicellular eukaryotes which develop as obligate intracellular parasites. They differentiate into resistant spores that are protected by a thick spore wall composed of a glycoprotein-rich outer layer or exospore and a chitin-rich inner layer or endospore. In this study performed on the silkworm pathogen Nosema bombycis, we analyzed the spore wall proteins (SWPs) by proteomic-based approaches, MALDI-TOF MS and LC-MS/MS, and 14 hypothetical spore wall proteins (HSWPs) or peptides were obtained in total. Furthermore, we have examined the SWPs by SDS-PAGE and three main spore wall peptides were detected with molecular weights of 32.7,kDa (SWP32), 30.4,kDa (SWP30), and 25.3,kDa (SWP25), respectively. By N-terminal amino acid residue sequencing, and searching the genomic DNA shotgun database of N. bombycis, the complete ORFs of SWP30 and SWP32 were obtained, which encode for a 278- and a 316-amino acid peptide, respectively. Mouse polyclonal antibodies were raised against SWP30 and SWP32 recombinant proteins produced in Escherichia coli, and the results of indirect immunofluorescence assay (IFA) and immunoelectron microscopy (IEM) analyses indicated SWP30 to be an endosporal protein while SWP32 was shown to be an exosporal protein. Both SWP30 and SWP32 are included in the 14 HSWPs identified by MS, confirming the results of the proteomic-based approaches. (GenBankÔ, EMBL and DDBJ accession numbers: NbHSWP1,NbHSWP12, accession no. EF683101,EF683112. NbHSWP13 and NbHSWP14, accession no. EU179719 and EU179720). [source] Differential action of bradykinin on intrarenal regional perfusion in the rat: waning effect in the cortex and major impact in the medullaTHE JOURNAL OF PHYSIOLOGY, Issue 15 2009ena B The renal kallikrein,kinin system is involved in the control of the intrarenal circulation and arterial pressure but bradykinin (Bk) effects on perfusion of individual kidney zones have not been examined in detail. Effects of Bk infused into renal artery, renal cortex or medulla on perfusion of whole kidney (RBF, renal artery probe) and of the cortex, outer- and inner medulla (CBF, OMBF, IMBF: laser-Doppler fluxes), were examined in anaesthetized rats. Renal artery infusion of Bk, 0.3,0.6 mg kg,1 h,1, induced no sustained increase in RBF or CBF. OMBF and IMBF increased initially 6 or 16%, respectively; only the IMBF increase (+10%) was sustained. Pre-treatment with l -NAME, 2.4 mg kg,1i.v., prevented the sustained but not initial transient elevation of medullary perfusion. Intracortical Bk infusion, 0.75,1.5 mg kg,1 h,1, did not alter RBF or CBF but caused a sustained 33% increase in IMBF. Intramedullary Bk, 0.3 mg kg,1 h,1, did not alter RBF or CBF but caused sustained increases in OMBF (+10%) and IMBF (+23%). These responses were not altered by pre-treatment with 1-aminobenzotriazole, 10 mg kg,1i.v., a cytochrome P-450 (CYP450) inhibitor, but were prevented or significantly attenuated by l -NAME or intramedullary clotrimazole, 3.9 mg kg,1 h,1, an inhibitor of CYP450 epoxygenase and of calcium-dependent K+ channels (KCa). Thus, cortical vasodilatation induced by Bk is only transient so that the agent is unlikely to control perfusion of the cortex. Bk selectively increases perfusion of the medulla, especially of its inner layer, via activation of the NO system and of KCa channels. [source] Turbulent flows on forested hilly terrain: the recirculation regionTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 625 2007D. Poggi Abstract A number of analytical and numerical studies employing first-order closure principles have suggested that canopy flows on gentle sinusoidal hills feature a recirculation region, situated on the lee side, that can dramatically affect scalar transfer between the biosphere and the atmosphere. To date, the onset of this region, and its effects on bulk flow properties, have not been experimentally investigated. We study the applicability of first-order closure schemes jointly with the properties of this recirculation region, using detailed laser Doppler anemometry (LDA) measurements. These experiments are conducted in a neutrally stratified boundary-layer flow within a large flume over a train of gentle and narrow hills. The canopy is composed of an array of vertical cylinders with a frontal-area index concentrated in the upper third, to resemble a tall hardwood forest at maximum leaf area. The LDA measurements are recorded for both sparse and dense canopies. We find that, while the onset of a recirculation region is ambiguous in the sparse-canopy case, it is well delineated in the dense-canopy case. This finding constitutes the first experimental evidence confirming the analytical and numerical model predictions concerning this region in dense canopies on gentle hills. Moreover, we show that the presence of the recirculation region can explain the anomalous pressure variation across the hill (first reported in numerical simulations) using an ,effective hill shape' function. Detailed momentum-flux measurements show, surprisingly, that the effective mixing length leff within the canopy and in the inner layer is not significantly affected by the recirculation region. We expected leff to be comparable to the size of the vortex responsible for the recirculation zone, but the measurements show that leff maintains its canonical canopy turbulence shape. Using laser-induced fluorescence (LIF) measurements, we find that the recirculation region is not characterized by a classical ,rotor', but by a highly intermittent zone with alternating positive and negative velocity values in the lower layers of the canopy. These LIF measurements may explain why leff maintains its canonical canopy turbulence shape in the recirculation region. The LIF measurements also show that the main mechanism for scalar transfer within the recirculation region is a sequence of accumulation,ejection episodes that are quasi-periodic in nature. Copyright © 2007 Royal Meteorological Society [source] Structural and Histochemical Studies on the Teleostean Bulbus ArteriosusANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 6 2009I. L. Leknes Summary The structure and histochemical properties of the bulbus arteriosus in two species from an evolutionary old teleost family, Characidae, and in three modern teleosts, family Cichlidae, are described. The bulbar wall was composed of an outer layer, a middle layer and a strongly folded inner layer covered by a thick, granule-rich endothelial cell layer towards the lumen. One of the cichlid species (Thorichthys meeki) was injected intraperitoneally with horse ferritin; the endothelial cell layer of the heart atrium and ventricle displayed high ability to endocytose ferritin particles from the blood stream, but the corresponding layer in the bulbus arteriosus displayed no such uptake. This finding suggests that the bulbar endothelial cell layer plays no scavenger or immunological blood cleansing roles in this species. The bulbar endothelial cell granules were strongly coloured by periodic acid,Schiff (PAS) in the present cichlids, but weakly coloured by PAS in the present characids. These cell layers were uncoloured by alkaline carmine in ethanol in both cichlids and characids. The negative carmine test combined with a positive PAS test for the bulbar endothelial cell layer in the present cichlids indicates that these cells contain only small amounts of polysaccharides. The weak PAS-colouring for the bulbar endothelial cell layer in characids indicates a very low content of sugars in these cells. These findings together with the fact that this cell layer in the present cichlids and characids was nearly uncoloured when treated with orcein, Heidenhain's Azan or Schmorl's solutions for elastic materials suggest that the bulbar endothelial granules do not play any role in the blood cleansing or in the rebuilding or maintenance of the ground substance or elastic material in the bulbar wall. Probably, the granules in the bulbar endothelial cell layer in the present species contain mainly proteins, connected to some PAS-positive polysaccharides to enhance their solubility. [source] Microscopic detection of IgY-Fc binding signal in the inner layers of ovarian follicular tissue in quailANIMAL SCIENCE JOURNAL, Issue 5 2010Kohji KITAGUCHI ABSTRACT In avian species, it has been assumed that an Fc receptor in the ovarian follicles mediates immunoglobulin Y (IgY) transport into the yolk. However, no such receptor responsible for IgY has been identified to date. To examine potential IgY binding activity in the entire ovarian follicle, whole-mount sections of quail ovarian follicle were incubated with the Fc fragment of chicken IgY (cIgY). Whole-mount frozen sections of the second largest ovarian follicle were prepared, and then the sections were incubated with digoxigenin-labeled Fc or Fab fragments of cIgY. Microscopic observation revealed that incubation with the cIgY-Fc fragment produced a binding signal in the inner layer of the ovarian follicular tissues, most likely in the granulosa cell layer. However, no such signal was detected when the sections were incubated with cIgY-Fab. Coincubation of the ovarian sections with Alexa488-labeled cIgY-Fc and antiserum raised against ZP1, an envelope protein specifically localized in the perivitelline layer, demonstrated that the source of the Fc binding signals partly coincided with the perivitelline layer. In conclusion, our data suggest that potential IgY binding substances interacting with the Fc domain are present in the inner layers of ovarian follicular tissues, most likely in the granulosa cell layer and/or in the perivitelline layer. [source] Iris melanoma in 12-year-old boyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 5 2006Tu A Tran MBBS Abstract A 12-year-old boy presented with an incidental finding of an iris lesion after blunt injury. Ocular examination revealed a large atypical brown vascular nodule in the nasal iris, extending to the pupillary margin. There were smaller scattered nodules scattered within the iris and anterior chamber. Ultrasound biomicroscopy examination revealed no tumour behind the iris. Fundal examination findings were normal. Sector iridectomy revealed mixed spindle and epitheliod melanoma. The eye was enucleated. Histopathologic examination confirmed malignant melanoma confined to the iridocorneal angle, iris, ciliary body and inner layer of the anterior sclera. Iris melanomas are very rare in the prepubertal age group. [source] The salmon vertebral body develops through mineralization of two preformed tissues that are encompassed by two layers of boneJOURNAL OF ANATOMY, Issue 2 2005Kari Nordvik Abstract The teleost backbone consists of amphicoelous vertebrae and intervertebral ligaments, both of which include notochord-derived structures. On the basis of a sequential developmental study of the vertebral column of Atlantic salmon (Salmo salar L.) from the egg stage up to early fry stage (300,2500 day-degrees) we show that the vertebral body consists of four layers or compartments, two of which are formed through mineralization of preformed collagenous tissue (the notochordal sheath and the intervertebral ligament) and two of which are formed through ossification. The three inner layers have ordered lamellar collagen matrixes, which alternate perpendicularly from layer to layer, whereas the outer layer consists of cancellous bone with a woven matrix. The bone layers also differ in osteocyte content. In this study we describe the structural details of the layers, and their modes of formation. The results are compared with previous descriptions, and possible phylogenetic implications are discussed. [source] Determination of cosmetic ingredients causing extrusion-coated and adhesive joint multilayer packaging delaminationPACKAGING TECHNOLOGY AND SCIENCE, Issue 7 2009Álvaro Garrido-López Abstract In order to study the effect of several compounds on packaging stability, different cosmetic ingredients at two concentration levels were added to a NeoPCL® (Acofarma, Terrassa, Spain) water emulsion, and the preparations packed in sachets and stored at 40°C during 3 months. After that, the packaging was subjected to a T-peel test and headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS) analysis. The HS-SPME-GC-MS analyses were performed using a 75,,m carboxen polydimethylsiloxane fibre to check for the presence of the studied analytes in the inner layers. The study revealed that the presence of a phenyl and a hydroxyl group in the compound structure lead to an important loss of adhesion between packaging layers joined by an adhesive. The interaction between the cosmetic ingredient and the adhesive was proposed as the main cause of the loss of adhesion. However, extrusion-coating packaging was more susceptible to delamination, particularly with the volatile compounds. Copyright © 2009 John Wiley & Sons, Ltd. [source] Delamination of multilayer packaging caused by exfoliating cream ingredientsPACKAGING TECHNOLOGY AND SCIENCE, Issue 3 2007Gustavo Ortiz Abstract Exfoliating creams were packed in sachets of composite packaging consisting of polyethylene, aluminium and polyester layers stuck together by polyurethane adhesive, and they were kept in an oven at 40°C in order to accelerate the delamination process. The sachets were then delaminated and the resulting layers were analysed. A headspace solid-phase microextraction mass spectrometry method (HS,SPME,GC,MS) using a 75µm carboxen polydimethylsiloxane fibre was used to identify the compounds migrating from the exfoliating creams through the polyethylene layer to the aluminium interface and suspected to be responsible for packaging delamination. Several volatile compounds used in the cosmetic industry as perfumes, fixing agents and preservatives, such as menthol, dihydromyrcenol and 2-phenoxyethanol, were detected in the aluminium/polyester delaminated layer. The exfoliating creams were also analysed by HS,SPME,GC,MS. The study of loss of adhesion of the laminated material exposed to the exfoliating products revealed that the product with a higher concentration of 2-phenoxyethanol caused a faster decrease in adhesion strength, but the lower adhesion values were found in products with higher concentrations of menthol and dihydromyrcenol. The results obtained showed that the analytical method used was suitable for identifying volatile compounds that migrate through polyethylene to the inner layers of the packaging of exfoliating products, as well as for providing prior information on which products may be difficult to package in sachets. Copyright © 2006 John Wiley & Sons, Ltd. [source] Half-metallicity and magnetism at Heusler alloy surfaces: Co2MSi(001) (M = Ti, Cr)PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2008Ying Jiu Jin Abstract We investigated the electronic structures, magnetism, and half-metallicity at the (001) surfaces of full-Heusler alloys, Co2MSi (M = Ti, Cr), by using the all-electron full-potential linearized augmented plane wave method within the generalized gradient approximation. Both the Co-terminated (Co-term) and the MSi-terminated (MSi-term) surfaces were considered. From the calculated atom-resolved density of states, we found that the half-metallicity was destroyed at the Co-term surfaces for both alloys. The electronic structures at the MSi-term surfaces of the two alloys showed much different behavior. The half-metallicity was retained at the TiSi-term for Co2TiSi(001) but the minority spin gap was much reduced due to surface states located just below the Fermi level. On the other hand the half-metallicity was destroyed at the CrSi-term of Co2CrSi(001) due to the surface states located at the Fermi level. The calculated magnetic moment of the surface Co atom of the Co-term for Co2CrSi(001) was increased slightly to 1.05,B with respect to that of the deep inner layers (,1.00,B), while that for Co2TiSi(001) was decreased to 0.88,B. Large enhancement of the magnetic moment was found for the surface Ti atoms at TiSi-term of Co2TiSi(001) and Cr atoms at CrSi-term of Co2CrSi(001) with values of 0.07,B and 2.91(B, respectively. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Plastid differentiation and chlorophyll biosynthesis in different leaf layers of white cabbage (Brassica oleracea cv. capitata)PHYSIOLOGIA PLANTARUM, Issue 3 2004Katalin Solymosi The contents of protochlorophyllide, protochlorophyll and chlorophyll together with the native arrangements of the pigments and the plastid ultrastructure were studied in different leaf layers of white cabbage (Brassica oleracea cv. capitata) using absorption, 77 K fluorescence spectroscopy and transmission electron microscopy. The developmental stage of the leaves was determined using the differentiation of the stoma complexes as seen by scanning electron microscopy and light microscopy. The pigment content showed a gradual decrease from the outer leaf layer towards the central leaves. The innermost leaves were in a primordial stage in many aspects; they were large but had typical proplastids with few simple inner membranes, and contained protochlorophyllide and its esters in a 2 : 1 ratio and no chlorophyll. Short-wavelength, not flash-photoactive protochlorophyllide and/or protochlorophyll forms emitting at 629 and 636 nm were dominant in the innermost leaves. These leaves also had small amounts of the 644 and 654 nm emitting, flash-photoactive protochlorophyllide forms. Rarely prolamellar bodies were observed in this layer. The outermost leaves had the usual characteristics of fully developed green leaves. The intermediary layers contained chlorophyll a and chlorophyll b besides the protochlorophyll(ide) pigments and had various intermediary developmental stages. Spectroscopically two types of intermediary leaves could be distinguished: one with only a 680 nm emitting chlorophyll a form and a second with bands at 685, 695 and 730 nm, corresponding to chlorophyll,protein complexes of green leaves. In these leaves, a large variety of chloroplasts were found. The data of this work show that etioplasts, etio-chloroplasts or chloro-etioplasts as well as etiolated leaves do exist in the nature and not only under laboratory conditions. The specificity of cabbage leaves compared with those of dark-grown seedlings is the retained primordial or intermediary developmental stage of leaves in the inner layers for very long (even for a few month) period. This opens new developmental routes leading to formation of specially developed plastids in the various cabbage leaf layers. The study of these plastids provided new information for a better understanding of the plastid differentiation and the greening process. [source] Microscopic detection of IgY-Fc binding signal in the inner layers of ovarian follicular tissue in quailANIMAL SCIENCE JOURNAL, Issue 5 2010Kohji KITAGUCHI ABSTRACT In avian species, it has been assumed that an Fc receptor in the ovarian follicles mediates immunoglobulin Y (IgY) transport into the yolk. However, no such receptor responsible for IgY has been identified to date. To examine potential IgY binding activity in the entire ovarian follicle, whole-mount sections of quail ovarian follicle were incubated with the Fc fragment of chicken IgY (cIgY). Whole-mount frozen sections of the second largest ovarian follicle were prepared, and then the sections were incubated with digoxigenin-labeled Fc or Fab fragments of cIgY. Microscopic observation revealed that incubation with the cIgY-Fc fragment produced a binding signal in the inner layer of the ovarian follicular tissues, most likely in the granulosa cell layer. However, no such signal was detected when the sections were incubated with cIgY-Fab. Coincubation of the ovarian sections with Alexa488-labeled cIgY-Fc and antiserum raised against ZP1, an envelope protein specifically localized in the perivitelline layer, demonstrated that the source of the Fc binding signals partly coincided with the perivitelline layer. In conclusion, our data suggest that potential IgY binding substances interacting with the Fc domain are present in the inner layers of ovarian follicular tissues, most likely in the granulosa cell layer and/or in the perivitelline layer. [source] Histology of highly echolucent regions in optical coherence tomography images from two patients with sirolimus-eluting stent restenosis,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2010Hiroyuki Nagai MD Abstract We report on two patients with sirolimus-eluting stent (SES) restenosis lesions who showed highly echolucent regions by optical coherence tomography (OCT) and who could be assessed histologically after removal by directional coronary atherectomy (DCA). One restenosis lesion had a bilayer structure of hyperechoic outer layers and highly echolucent inner layers on OCT images and histologically exhibited myxomatous neointima tissue in the highly echolucent regions; another restenosis case showed patchy and highly echolucent regions throughout the layers and its histology revealed fibrin thrombosis. We should be aware that patterns of echolucent on OCT images may have various histology. OCT allows the visualization of fine lesions that conventional intravascular ultrasound (IVUS) cannot provide. The OCT images of drug-eluting stent restenosis lesions often show echolucent regions [Shuzoh et al., EuroInterv 2006;1:484]. However, no histological study of the lesions has been reported to date. Here we report on two patients with SES restenosis lesions that showed highly echolucent regions by OCT and that could be assessed histologically after removal by DCA. © 2009 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||