Silicon in Imperata cylindrica (L.) P. Beauv: content, distribution, and ultrastructure.

Science.gov (United States)

Rufo, Lourdes; Franco, Alejandro; de la Fuente, Vicenta

2014-07-01

Silicon concentration, distribution, and ultrastructure of silicon deposits in the Poaceae Imperata cylindrica (L.) P. Beauv. have been studied. This grass, known for its medicinal uses and also for Fe hyperaccumulation and biomineralization capacities, showed a concentration of silicon of 13,705 ± 9,607 mg/kg dry weight. Silicon was found as an important constituent of cell walls of the epidermis of the whole plant. Silica deposits were found in silica bodies, endodermis, and different cells with silicon-collapsed lumen as bulliforms, cortical, and sclerenchyma cells. Transmission electron microscope observations of these deposits revealed an amorphous material of an ultrastructure similar to that previously reported in silica bodies of other Poaceae.

Microstructure and Ultrastructure Alterations in the Pallium of Immature Mice Exposed to Cadmium.

Science.gov (United States)

Yang, X F; Han, Q G; Liu, D Y; Zhang, H T; Fan, G Y; Ma, J Y; Wang, Z L

2016-11-01

The aim of this study was to investigate microstructure and ultrastructure alterations in the pallium of immature mice exposed to cadmium. Forty immature mice were randomly divided into control, 1/100 LD 50 (1.87 mg/kg, low), 1/50 LD 50 (3.74 mg/kg, medium), and 1/25 LD 50 (7.48 mg/kg, high) dose groups. After oral cadmium exposure for 40 days, the pallium of mice was obtained for microstructure and ultrastructure studies. The results showed that both microstructure and ultrastructure alterations of the pallium were observed in all treated mice and the most obvious alterations were in the high dose group. Microstructural analysis showed seriously congested capillary in the pia mater of the pallium in the high cadmium group. Meanwhile, vacuolar degenerate or karyopyknosis presented in some neurocytes, capillary quantity, and the number of apoptotic cells increased, some neurocytes became hypertrophy, the pia mater separated from the cortex, and local hemorrhage and accompanied inflammatory cell infiltration were also observed. Ultrastructural analysis showed that rough endoplasmic reticulum was expanded, heterochromatin marginalized, perinuclear space distinctly broadened, swelling and vacuolization mitochondria appeared, synapse was swelling, presynaptic and postsynaptic membranes presented fusion, and most of mitochondrial cristae were ambiguous. The results indicated that cadmium exposure for 40 days induced dose-dependent microstructure and ultrastructure alterations in pallium of immature mice.

The ultra-structural organization of the elastic network in the intra- and inter-lamellar matrix of the intervertebral disc.

Science.gov (United States)

Tavakoli, J; Elliott, D M; Costi, J J

2017-08-01

The inter-lamellar matrix (ILM)-located between adjacent lamellae of the annulus fibrosus-consists of a complex structure of elastic fibers, while elastic fibers of the intra-lamellar region are aligned predominantly parallel to the collagen fibers. The organization of elastic fibers under low magnification, in both inter- and intra-lamellar regions, was studied by light microscopic analysis of histologically prepared samples; however, little is known about their ultrastructure. An ultrastructural visualization of elastic fibers in the inter-lamellar matrix is crucial for describing their contribution to structural integrity, as well as mechanical properties of the annulus fibrosus. The aims of this study were twofold: first, to present an ultrastructural analysis of the elastic fiber network in the ILM and intra-lamellar region, including cross section (CS) and in-plane (IP) lamellae, of the AF using Scanning Electron Microscopy (SEM) and second, to -compare the elastic fiber orientation between the ILM and intra-lamellar region. Four samples (lumbar sheep discs) from adjacent sections (30μm thickness) of anterior annulus were partially digested by a developed NaOH-sonication method for visualization of elastic fibers by SEM. Elastic fiber orientation and distribution were quantified relative to the tangential to circumferential reference axis. Visualization of the ILM under high magnification revealed a dense network of elastic fibers that has not been previously described. Within the ILM, elastic fibers form a complex network, consisting of different size and shape fibers, which differed to those located in the intra-lamellar region. For both regions, the majority of fibers were oriented near 0° with respect to tangential to circumferential (TCD) direction and two minor symmetrical orientations of approximately±45°. Statistically, the orientation of elastic fibers between the ILM and intra-lamellar region was not different (p=0.171). The present study used

The ultrastructure of pollen grain surface in allotetraploid petunia (Petunia hybrida hort. superbissima as revealed by scanning electron microscopy

Directory of Open Access Journals (Sweden)

S. Muszyński

2015-01-01

Full Text Available The ultrastructure of pollen grain surface in allotetraploid petunias was analyzed by scanning electron microscopy. The pollen grain wall is developed into characteristic pattern of convulations.

Transmission electron microscopy, fluorescence microscopy, and confocal raman microscopic analysis of ultrastructural and compositional heterogeneity of Cornus alba L. wood cell wall.

Science.gov (United States)

Ma, Jianfeng; Ji, Zhe; Zhou, Xia; Zhang, Zhiheng; Xu, Feng

2013-02-01

Transmission electron microscopy (TEM), fluorescence microscopy, and confocal Raman microscopy can be used to characterize ultrastructural and compositional heterogeneity of plant cell walls. In this study, TEM observations revealed the ultrastructural characterization of Cornus alba L. fiber, vessel, axial parenchyma, ray parenchyma, and pit membrane between cells, notably with the ray parenchyma consisting of two well-defined layers. Fluorescence microscopy evidenced that cell corner middle lamella was more lignified than adjacent compound middle lamella and secondary wall with variation in lignification level from cell to cell. In situ Raman images showed that the inhomogeneity in cell wall components (cellulose and lignin) among different cells and within morphologically distinct cell wall layers. As the significant precursors of lignin biosynthesis, the pattern of coniferyl alcohol and aldehyde (joint abbreviation Lignin-CAA for both structures) distribution in fiber cell wall was also identified by Raman images, with higher concentration occurring in the fiber secondary wall where there was the highest cellulose concentration. Moreover, noteworthy was the observation that higher concentration of lignin and very minor amounts of cellulose were visualized in the pit membrane areas. These complementary microanalytical methods provide more accurate and complete information with regard to ultrastructural and compositional characterization of plant cell walls.

Analysis of the changes in the basal cell region of oral lichen planus: An ultrastructural study

Science.gov (United States)

Paul, Mayura; Shetty, Devi Charan

2013-01-01

Context: Oral lichen planus (OLP) affects 0.5-1% of the total world's population. The histological features of oral lichen planus were first described by Dubreuill in 1906. Despite the advent of various techniques, the etiology of lichen planus remains obscure, although many theories for the etiology have been proposed. Aims: By studying OLP electron microscopically, we shall be emphasizing on the cells and its interactions in specific/altered surroundings which would help us in hypothesizing the effects of its specific cell-to-cell interactions. Materials and Methods: A total of 20 cases of oral lichen planus were selected and categorized into erosive and nonerosive forms based upon clinical pattern and confirmed as lichen planus by histopathological analysis. Tissue specimens thus obtained were cut into two halves and fixed in appropriate fixatives, i.e., neutral buffered formalin for paraffin-embedded hematoxylin and eosin stained sections and 2.5% glutaraldehyde and 2% paraformaldehyde for electron microscopic purpose respectively. Results: Ultrastructural comparison among the two forms showed significant differences between them. The basal layer showed cytoplasmic processes, intercellular spaces, desmosomes, nuclei, and signs of degeneration. The erosive form showed elongated, narrow or irregular cytoplasmic projections whereas the nonerosive showed short and broad based projections. Conclusions: The present study confirms the ultrastructural findings of basal cells in OLP with previous authors findings. Besides this, the categorization of the ultrastructural differences between erosive and nonerosive has raised the question of difference in the probable cellular and molecular mechanism between erosive and nonerosive forms. PMID:23798823

Super-Resolution Microscopy Reveals the Native Ultrastructure of the Erythrocyte Cytoskeleton

Directory of Open Access Journals (Sweden)

Leiting Pan

2018-01-01

Full Text Available The erythrocyte cytoskeleton is a textbook prototype for the submembrane cytoskeleton of metazoan cells. While early experiments suggest a triangular network of actin-based junctional complexes connected by ∼200-nm-long spectrin tetramers, later studies indicate much smaller junction-to-junction distances in the range of 25-60 nm. Through super-resolution microscopy, we resolve the native ultrastructure of the cytoskeleton of membrane-preserved erythrocytes for the N and C termini of β-spectrin, F-actin, protein 4.1, tropomodulin, and adducin. This allows us to determine an ∼80-nm junction-to-junction distance, a length consistent with relaxed spectrin tetramers and theories based on spectrin abundance. Through two-color data, we further show that the cytoskeleton meshwork often contains nanoscale voids where the cell membrane remains intact and that actin filaments and capping proteins localize to a subset of, but not all, junctional complexes. Together, our results call for a reassessment of the structure and function of the submembrane cytoskeleton.

Pb and Cd on growth, leaf ultrastructure and essential oil yield mint (Mentha arvensis L.

Directory of Open Access Journals (Sweden)

Caroline Nery Jezler

2015-03-01

Full Text Available Contamination of medicinal plants with heavy metals as Pb and Cd can affect the growth and the essential oil production of the plants and represent a risk to those who consume as medicine. This study aimed to evaluate the effects of absorption and localization of Pb and Cd on growth, ultrastructural aspects of leaves and essential oil yield and composition of Mentha arvensis, applied on the soil with increasing concentrations (8, 16, 32, 64 and 128mg kg-1. There was a differential absorption of Pb and Cd by M. arvensis mainly concentrated in the roots. Pb was found in small amounts in the leaves while Cd largely exceeded the safety limit without symptoms of toxicity. The ultrastructural analysis revealed the metal accumulation on vesicles surrounding the mitochondria and the presence of electron dense deposits surrounding the mitochondria, nucleus and chloroplasts. Little changes caused by Pb and Cd application were not enough to affect the growth and essential oil yield and composition of M. arvensis

Ultrastructural Changes in the Liver of Intravenous Heroin Addicts

Directory of Open Access Journals (Sweden)

Goran Ilić

2010-02-01

Full Text Available The ultrastructural research has a decisive role in gathering the knowledge on the liver’s response to the influence of some drugs. The aim of the study was to perform an ultrastructurai analysis of the liver in chronic intravenous heroin addicts.The study involved the autopsy conducted on 40 bodies of intravenous heroin addicts and 10 control autopsies. The liver tissue was fixed in glutaraldehyde and moulded with epon for investigation purposes of ultrastructural changes. The analysis was performed using the method of transmission electron microscopy.In the group of intravenous heroin addicts, the liver autopsy samples showed degenerative vesicular and fat changes, chronic active and persistent hepatitis, cirrhosis, reduction in the amount of glycogen in hepatocytes, as well as the Kupffer cell’s dominant hypertrophy. Various changes occur in organelles, plasma membrane of hepatocytes and biliary channels as well as in the nucleus.The most important ultrastructural findings include: hyperplasia and hypertrophy of the smooth endoplasmic reticulum, which is histologically proven vesicular degeneration of hepatocyte occurring as a result of the increased synthesis of enzymes of smooth endoplasmic reticulum due to chronic intravenous heroin intake, and the presence of continuous basal membrane followed by transformation of the sinusoids into capillaries (in the cases of chronic active hepatitis and cirrhosis which leads to a disorder of microcirculation and further progress of cirrhosis.

Developmental and Ultrastructural Characterization and Phylogenetic Analysis of Trypanosoma herthameyeri n. sp. of Brazilian Leptodactilydae Frogs.

Science.gov (United States)

Attias, Márcia; Sato, Lyslaine H; Ferreira, Robson C; Takata, Carmen S A; Campaner, Marta; Camargo, Erney P; Teixeira, Marta M G; de Souza, Wanderley

2016-09-01

We described the phylogenetic affiliation, development in cultures and ultrastructural features of a trypanosome of Leptodacylus chaquensis from the Pantanal biome of Brazil. In the inferred phylogeny, this trypanosome nested into the Anura clade of the basal Aquatic clade of Trypanosoma, but was separate from all known species within this clade. This finding enabled us to describe it as Trypanosoma herthameyeri n. sp., which also infects other Leptodacylus species from the Pantanal and Caatinga biomes. Trypanosoma herthameyeri multiplies as small rounded forms clumped together and evolving into multiple-fission forms and rosettes of epimastigotes released as long forms with long flagella; scarce trypomastigotes and glove-like forms are common in stationary-phase cultures. For the first time, a trypanosome from an amphibian was observed by field emission scanning electron microscopy, revealing a cytostome opening, well-developed flagellar lamella, and many grooves in pumpkin-like forms. Transmission electron microscopy showed highly developed Golgi complexes, relaxed catenation of KDNA, and a rich set of spongiome tubules in a regular parallel arrangement to the flagellar pocket as confirmed by electron tomography. Considering the basal position in the phylogenetic tree, developmental and ultrastructural data of T. herthameyeri are valuable for evolutionary studies of trypanosome architecture and cell biology. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

Ultrastructural researches on rabbit myxomatosis. Lymphnodal lesions.

Science.gov (United States)

Marcato, P S; Simoni, P

1977-07-01

Ultrastructural examination of head and neck lymph nodes in rabbits with spontaneous subacute myxomatosis showed fusion of immature reticuloendothelial cells which lead to the formation of polykarocytes. There was no ultrastructural evidence of viral infection of these polykaryocytes. Histiosyncytial lymphadenitis can be considered a specific lesion of myxomatosis.

Ultrastructural morphometry of parotid acinar cells following fractionated irradiation

International Nuclear Information System (INIS)

Grehn, A.-L.; Gustafsson, H.; Franzen, L.; Thornell, L.-E.; Henriksson, R.

1997-01-01

The aim of this study was to evaluate the long term effects on the ultrastructure of parotid glands after fractionated irradiation. The method implemented involved 5 x 6 Gy and 5 x 8 Gy, Monday to Friday 6 MV photons. By unilateral irradiation, the contralateral parotid gland served as a control. Although irradiation diminished the acinar cell density in light microscopic sections from 75 to 32% after 5 x 8 Gy of irradiation, ultrastructural morphometry could not detect any statistically significant differences in acinar cell size, nuclear size, nuclear density, granule area, mean granule size, or granule density. In general, greater differences were seen between rats receiving 30 or 40 Gy, on both the irradiated and the control side, than between the irradiated side and the control side. This was interpreted as due to differences in the nutritional state of the animals. This analysis concluded that individual acinar cells that survive irradiation seem not to be damaged in the long term when evaluated at the ultrastructural level. The study further stresses the importance of adequate sampling sizes and the use of adequate controls. (author)

Ultrastructural demonstration of chemical modification of melanogenesis in hairless mouse skin

International Nuclear Information System (INIS)

Nishimura, M.; Gellin, G.A.; Hoshino, S.; Epstein, J.H.; Epstein, W.L.; Fukuyama, K.

1982-01-01

We investigated chemical and physical modifications of the genetically determined ultrastructure of melanosomes. The flank skin of hairless mice was treated with ultraviolet energy (UV) shorter than 320 nm or with a combination of a photosensitizer and UV (PUVA treatment). All melanosomes in the induced melanocytes and those in resident melanocytes in the ear skin showed eumelanogenesis, although the degree of melanin deposition differed considerably according to the induction process. Eumelanogenesis was most advanced in the resident melanocytes while PUVA-induced melanocytes showed more immature premelanosomes. We then topically applied 4-tertiary butyl catechol on the skin. The depigmenting agent caused an appearance of pheomelanosomes. The alteration in melanogenesis was seen most distinctly in premelanosomes of the PUVA-induced cells. Altered ultrastructure was also observed in matured melanosomes; this change was most apparent in the resident melanocytes. These findings indicate that cells with eumelanogenesis may undergo pheomelanogenesis. The present study demonstrated effects of chemicals on genetically determined function of melanocytes by quantitative analysis of melanosome ultrastructure

Air pollution effects on the ultrastructure of Phlomis fruticosa mesophyll cells

Energy Technology Data Exchange (ETDEWEB)

Psaras, G.K.; Christodoulakis, N.S.

1987-04-01

Plant physiologists and environmental scientists suggest that a basic effect of air pollution on plants leads towards the minimization of their productivity. On the other hand the action of individual pollutants on intact plants has been studied from biochemical as well as structural viewpoint. Thus the study of plant responses to SO/sub 2/ exposure revealed that this agent causes acute and chronic injury. Chronic injury results in chlorosis and subsequent necrosis due to destruction of chlorophylls and final chloroplast lysis. It has been documented that ultrastructural characteristics of leaves are affected prior to any visible injury. Electron microscope examination of SO/sub 2/ fumigated plant-attached leaves of Vicia faba revealed chloroplast thylakoids starting to swell whilst photosynthesis rate was drastically reduced. The first light microscope-detected effects of air pollution on the leaf structure of plants common in natural ecosystems of Athens metropolitan area, have been reported. A chlorosis phenomenon in Urginea maritima leaves as well as an indication of detrimental effects of Phlomis fruticosa mesophyll chloroplasts were documented. In this work further investigation has been undertaken in order to elucidate the precise effects of air pollution on the ultrastructure of the photosynthesizing mesophyll cells.

Dietary adaptions in the ultrastructure of dinosaur dentine.

Science.gov (United States)

Brink, Kirstin S; Chen, Yu-Cheng; Wu, Ya-Na; Liu, Wei-Min; Shieh, Dar-Bin; Huang, Timothy D; Sun, Chi-Kuang; Reisz, Robert R

2016-12-01

Teeth are key to understanding the feeding ecology of both extant and extinct vertebrates. Recent studies have highlighted the previously unrecognized complexity of dinosaur dentitions and how specific tooth tissues and tooth shapes differ between taxa with different diets. However, it is unknown how the ultrastructure of these tooth tissues contributes to the differences in feeding style between taxa. In this study, we use third harmonic generation microscopy and scanning electron microscopy to examine the ultrastructure of the dentine in herbivorous and carnivorous dinosaurs to understand how the structure of this tissue contributes to the overall utility of the tooth. Morphometric analyses of dentinal tubule diameter, density and branching rates reveal a strong signal for dietary preferences, with herbivorous saurischian and ornithischian dinosaurs consistently having higher dentinal tubule density than their carnivorous relatives. We hypothesize that this relates to the hardness of the dentine, where herbivorous taxa have dentine that is more resistant to breakage and wear at the dentine-enamel junction than carnivorous taxa. This study advocates the detailed study of dentine and the use of advanced microscopy techniques to understand the evolution of dentition and feeding ecology in extinct vertebrates. © 2016 The Author(s).

Morphological and ultrastructural studies on Ulva flexuosa subsp. pilifera (Chlorophyta from Poland

Directory of Open Access Journals (Sweden)

Beata Messyasz

2013-06-01

Full Text Available Ulva flexuosa subsp. pilifera (Kütz. M. J. Wynne 2005 (= Enteromorpha pilifera Kützing 1845 was previously found in Argentina, the Czech Republic, Germany, Hungary, Romania, Slovakia and Sweden, recently also in Poland. The genus Ulva was first time described as Enteromorpha. Interestingly, Enteromorpha is used nowadays as a synonym for Ulva, a development which is based on molecular data. The morphologies of both young and mature specimens were studied, and most life cycle stages could be observed. Further, the formation of calcium carbonate crystals on the surface of Ulva thalli seems to influence the arrangement of the cells. A detailed ultrastructural (TEM analysis of cell walls is presented. The TEM reveals in great details highly complex, irregular structures with stratification lines.

Inter-relationships of haplosporidians deduced from ultrastructural studies

NARCIS (Netherlands)

Hine, P.M.; Carnegie, R.B.; Burreson, E.M.; Engelsma, M.Y.

2009-01-01

We reviewed papers reporting haplosporidian ultrastructure to compare inter-relationships based on ultrastructure with those based on molecular data, to identify features that may be important in haplosporidian taxonomy, and to consider parasite taxonomy in relation to host taxonomy. There were

ATP Synthase Deficiency due to TMEM70 Mutation Leads to Ultrastructural Mitochondrial Degeneration and Is Amenable to Treatment

Directory of Open Access Journals (Sweden)

Anne K. Braczynski

2015-01-01

Full Text Available TMEM70 is involved in the biogenesis of mitochondrial ATP synthase and mutations in the TMEM70 gene impair oxidative phosphorylation. Herein, we report on pathology and treatment of ATP synthase deficiency in four siblings. A consanguineous family of Roma (Gipsy ethnic origin gave birth to 6 children of which 4 were affected presenting with dysmorphic features, failure to thrive, cardiomyopathy, metabolic crises, and 3-methylglutaconic aciduria as clinical symptoms. Genetic testing revealed a homozygous mutation (c.317-2A>G in the TMEM70 gene. While light microscopy was unremarkable, ultrastructural investigation of muscle tissue revealed accumulation of swollen degenerated mitochondria with lipid crystalloid inclusions, cristae aggregation, and exocytosis of mitochondrial material. Biochemical analysis of mitochondrial complexes showed an almost complete ATP synthase deficiency. Despite harbouring the same mutation, the clinical outcome in the four siblings was different. Two children died within 60 h after birth; the other two had recurrent life-threatening metabolic crises but were successfully managed with supplementation of anaplerotic amino acids, lipids, and symptomatic treatment during metabolic crisis. In summary, TMEM70 mutations can cause distinct ultrastructural mitochondrial degeneration and almost complete deficiency of ATP synthase but are still amenable to treatment.

Crystalline Ultrastructures, Inflammatory Elements, and Neoangiogenesis Are Present in Inconspicuous Aortic Valve Tissue

Directory of Open Access Journals (Sweden)

P. Dorfmüller

2010-01-01

Full Text Available Morbidity from calcific aortic valve disease (CAVD is increasing. Recent studies suggest early reversible changes involving inflammation and neoangiogenesis. We hypothesized that microcalcifications, chemokines, and growth factors are present in unaffected regions of calcific aortic valves. We studied aortic valves from 4 patients with CAVD and from 1 control, using immunohistochemistry, scanning electron microscopy, and infrared spectrography. We revealed clusters of capillary neovessels in calcified (ECC, to a lesser extent in noncalcified (ECN areas. Endothelial cells proved constant expression of SDF-1 in ECC, ECN, and endothelial cells from valvular surface (ECS. Its receptor CXCR4 was expressed in ECC. IL-6 expression correlated with CXCR4 staining and presence of lymphocytes. VEGF was expressed by ECS, its receptor by ECC and ECN. Crystalline ultrastructures were found on the surface of histologically noncalcified areas (HNCAs, spectrography revealed calcium hydroxylapatite. Our results demonstrate that crystalline ultrastructures are present in HNCAs, undergoing neoangiogenesis in an inflammatory context. These alterations could be an early witness of disease and an opening to therapy.

Alimentary Canal of the Adult Blow Fly, Chrysomya megacephala (F. (Diptera: Calliphoridae—Part I: Ultrastructure of Salivary Glands

Directory of Open Access Journals (Sweden)

Worachote Boonsriwong

2012-01-01

Full Text Available The salivary gland ultrastructure of the adult male blow fly, Chrysomya megacephala (F. (Diptera: Calliphoridae, was investigated at the ultrastructural level using light microscopy (LM, scanning electron microscopy (SEM, and transmission electron microscopy (TEM. The salivary glands are paired structures composed of a single median deferent duct bifurcated into two long, narrow efferent ducts connected to the coiled tubular glands. The SEM image of the gland surface revealed that the basal lamina is relatively smooth in general, but the whole surface appeared as a trace of rough swollen insertion by intense tracheal ramification. Ultrastructurally, the salivary gland is enclosed within the basal lamina, and interdigitation cytoplasmic extensions were apparent between the adjacent gland cells. The basement membrane appeared infoldings that is similar to the complex of the labyrinth channel. The cytoplasm characteristic of the gland revealed high activity, based on the abundance of noticeable secretory granules, either singly or in an aggregated reservoir. In addition, mitochondria were found to intersperse among rich parallel of arrays rough endoplasmic reticulum. Thick cuticle, which was well-delineated and electron dense, apically lined the gland compartments, with discontinuity of the double-layer cuticle revealing a trace of secretion discharged into the lumen. Gross anatomy of the adult salivary gland was markedly different from that of the third instar of the same species, and structural dissimilarity is discussed briefly.

Effect of the bendiocarb on the ultrastructure of rabbit skeletal muscle

Directory of Open Access Journals (Sweden)

Katarína Holovská

2017-01-01

Full Text Available Bendiocarb belongs to the group of carbamate insecticides that inhibit acetylcholinesterase. In agriculture, it is used to control a variety of insects, therefore it is important to examine every potential aspect of its toxicology. The aim of this study was to observe the effect of bendiocarb on the ultrastructure of the skeletal muscle in rabbits. Rabbits in all experimental groups received capsules of bendiocarb (96% Bendiocarb, Bayer, Germany per os daily at a dose of 5 mg/kg body weight. Samples of skeletal muscles were collected on days 10 and 20. On day 10 of the experiment, muscle fibres were not affected consistently. The observed changes were moderate and focal. Electron microscopy revealed dilatation of sarcoplasmic reticulum, and myofilament disorganization. On day 20 of the experiment, the ultrastructural changes in muscle fibres were more intense and more frequent. The most important alteration was the disruption of the sarcomeres due to the lysis of both thick and thin myofilaments. However, in the unchanged regions of muscle fibres a prominent mitochondrial swelling was observed. Many mitochondria lacked cristae and thus appeared as large membrane-bound cytoplasmic vesicles. The results presented in this study indicate that bendiocarb affects the ultrastructure of skeletal muscles. The intensity of damage (dissolution of myofilaments and disruption of sarcomeres was related to the duration of administration of bendiocarb.

Retinal adaptation to dim light vision in spectacled caimans (Caiman crocodilus fuscus): Analysis of retinal ultrastructure.

Science.gov (United States)

Karl, Anett; Agte, Silke; Zayas-Santiago, Astrid; Makarov, Felix N; Rivera, Yomarie; Benedikt, Jan; Francke, Mike; Reichenbach, Andreas; Skatchkov, Serguei N; Bringmann, Andreas

2018-05-19

oblique arrangement of many Müller cell trunks/processes in the inner plexiform layer and the large Müller cell somata in the inner nuclear layer may suggest that light guidance through Müller cells increases the visual sensitivity. Furthermore, an adaptation of the caiman retina to low light levels is strongly supported by detailed ultrastructural data of other retinal parts, e.g. by (i) the presence of a guanine-based retinal tapetum, (ii) the rod dominance of the retina, (iii) the presence of photoreceptor cell nuclei, which penetrate the outer limiting membrane, (iv) the relatively low densities of photoreceptor and neuronal cells which is compensated by (v) the presence of rods with long and thick outer segments, that may increase the probability of photon absorption. According to a cell number analysis, the central and temporal areas of the dorsal tapetal retina, which supports downward prey detection in darker water, are the sites of the highest diurnal contrast/color vision, i.e. cone vision and of the highest retinal light sensitivity, i.e. rod vision. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sperm ultrastructure, morphometry, and abnormal morphology in American black bears (Ursus americanus).

Science.gov (United States)

Brito, L F C; Sertich, P L; Stull, G B; Rives, W; Knobbe, M

2010-11-01

The objective of this study was to describe sperm ultrastructure, morphometry, and abnormal morphology in American black bears. Electroejaculation was successful in 53.8% (7/13) of the attempts, but urine contamination was common. Epididymal sperm samples were also obtained from five bears. Sperm had a paddle-like head shape and the ultrastructure was similar to that of most other mammals. The most striking particularity of black bear sperm ultrastructure was a tightening of the nucleus in the equatorial region. Although the differences were not significant in all bears, the overall decrease in sperm nucleus dimensions during transport from the caput epididymis to the cauda suggested increasing compaction of the nucleus during maturation. For ejaculated sperm, nucleus length, width, and base width were 4.9, 3.7, and 1.8 μm, respectively, whereas sperm head length, width, and base width were 6.6, 4.8, and 2.3 μm, and midpiece, tail (including midpiece), and total sperm lengths were 9.8, 68.8, and 75.3 μm. Evaluation of sperm cytoplasmic droplets in the epididymis revealed that proximal droplets start migrating toward a distal position in the caput epididymis and that the process was mostly completed by the time sperm reached the cauda epididymis. The proportion of morphologically normal sperm in the ejaculate was 35.6%; the most prevalent sperm defects were distal cytoplasmic droplets and bent/coiled tails. The morphology of abnormal sperm and the underlying ultrastructural defects were similar to that in other large domestic animals thus suggesting similar underlying pathogenesis of specific sperm defects and similar effects on fertility. Copyright © 2010 Elsevier Inc. All rights reserved.

Physiological and Proteomics Analyses Reveal Low-Phosphorus Stress Affected the Regulation of Photosynthesis in Soybean.

Science.gov (United States)

Chu, Shanshan; Li, Hongyan; Zhang, Xiangqian; Yu, Kaiye; Chao, Maoni; Han, Suoyi; Zhang, Dan

2018-06-06

Previous studies have revealed a significant genetic relationship between phosphorus (P)-efficiency and photosynthesis-related traits in soybean. In this study, we used proteome profiling in combination with expression analysis, biochemical investigations, and leaf ultrastructural analysis to identify the underlying physiological and molecular responses. The expression analysis and ultrastructural analysis showed that the photosynthesis key genes were decreased at transcript levels and the leaf mesophyll and chloroplast were severely damaged after low-P stress. Approximately 55 protein spots showed changes under low-P condition by mass spectrometry, of which 17 were involved in various photosynthetic processes. Further analysis revealed the depression of photosynthesis caused by low-P stress mainly involves the regulation of leaf structure, adenosine triphosphate (ATP) synthesis, absorption and transportation of CO₂, photosynthetic electron transport, production of assimilatory power, and levels of enzymes related to the Calvin cycle. In summary, our findings indicated that the existence of a stringent relationship between P supply and the genomic control of photosynthesis in soybean. As an important strategy to protect soybean photosynthesis, P could maintain the stability of cell structure, up-regulate the enzymes’ activities, recover the process of photosystem II (PSII), and induce the expression of low-P responsive genes and proteins.

Ultrastructural cytochemical prospective study of adult acute lymphoblastic leukemia: detection of peroxidase activity in patients failing to respond to treatment.

Science.gov (United States)

Reiffers, J; Darmendrail, V; Larrue, J; Villenave, I; Bernard, P; Boisseau, M; Broustet, A

1981-08-15

Ultrastructural cytochemical studies revealed peroxidase activity in five of 25 adult patients with apparent null lymphoblastic leukemia (ALL) in whom the peroxidase reaction studied with light microscopy was negative. None of these 5 patients responded to a chemotherapy regimen used for adult ALL. The importance of ultrastructural cytochemistry which allows the recognition of myeloblastic differentiation in undifferentiated blast cells is also demonstrated. The correct classification of such cases may be important for prognosis because they appear to be resistant to the chemotherapy used in treating ALL.

Somatostatinoma: collision with neurofibroma and ultrastructural features.

Science.gov (United States)

Varikatt, W; Yong, J L C; Killingsworth, M C

2006-11-01

The clinical presentation, histopathology and immunoelectron microscopic features of two cases of duodenal somatostatinoma are described, one of which is a hitherto unreported example of a collision tumour with a neurofibroma. Ultrastructural morphometric immunoelectron microscopy studies revealed the presence of four types of cells in both tumours, but there was no difference in the proportions of these cells between the collision tumour and the non-collision tumour. Neurosecretory granules ranging in size from 255-815 nm were generally larger than those previously reported for somatostatinomas and somatostatin was identified in granules of all sizes across this range. Neither tumour was associated with the somatostatinoma syndrome comprising associated diabetes mellitis, steatorrhoea and cholelithiasis.

Cyanophytes on limestone rocks in the Szopczański Gorge (Pieniny Mountains – their ecomorphology and ultrastructure

Directory of Open Access Journals (Sweden)

Joanna Czerwik-Marcinkowska

2011-08-01

Full Text Available This study is devoted to the ecomorphology and ultrastructure of cyanophytes on limestone rocks collected in the Szopczański Gorge (Pieniny Mountains during the years 2006-2008. There were selected cyanophyte species for examination such as following: Nostoc microscopicum, Phormidium favosum, Leptolyngbya foveolarum, Tolypothrix distorta var. penicillatum, Pseudanabaena catenata. The ultrastructural analysis (TEM confirmed that the structure and placement of the thylakoids is genus/species specific.

Ultrastructural analysis of different human mesenchymal stem cells after in vitro expansion: a technical review

Directory of Open Access Journals (Sweden)

M. Miko

2015-10-01

Full Text Available Transmission electron microscopy reveals ultrastructural details of cells, and it is a valuable method for studying cell organelles. That is why we used this method for detailed morphological description of different adult tissuederived stem cells, focusing on the morphological signs of their functions (proteosynthetic activity, exchange with external environment, etc. and their comparison. Preparing a specimen from the cell culture suitable for transmission electron microscopy is, however, much more challenging than routine tissue processing for normal histological examination. There are several issues that need to be solved while working with cell pellets instead of solid tissue. Here we describe a simple protocol for the isolation and culture of mesenchymal stem cells from different adult tissues, with applications to stem cell biology and regenerative medicine. Since we are working with population of cells that was obtained after many days of passaging, very efficient and gentle procedures are highly necessary. We demonstrated that our semi-conservative approach regarding to histological techniques and processing of cells for transmission electron microscopy is a well reproducible procedure which results in quality pictures and images of cell populations with minimum distortions and artifacts. We also commented about riskiest steps and histochemical issues (e.g., precise pH, temperature while preparing the specimen. We bring full and detailed procedures of fixation, post-fixation, infiltration, embedding, polymerization and contrasting of cell obtained from in vitro cell and tissue cultures, with modifications according to our experience. All this steps are essential for us to know more about adult stem cells derived from different sources or about other random cell populations. The knowledge about detailed ultra-structure of adult stem cells cultured in vitro are also essential for their using in regenerative medicine and tissue engineering.

Ultrastructural Analysis of Different Human Mesenchymal Stem Cells After in Vitro Expansion: A Technical Review

Science.gov (United States)

Danišovič, Ľ.; Majidi, A.; Varga, I.

2015-01-01

Transmission electron microscopy reveals ultrastructural details of cells, and it is a valuable method for studying cell organelles. That is why we used this method for detailed morphological description of different adult tissue-derived stem cells, focusing on the morphological signs of their functions (proteosynthetic activity, exchange with external environment, etc.) and their comparison. Preparing a specimen from the cell culture suitable for transmission electron microscopy is, however, much more challenging than routine tissue processing for normal histological examination. There are several issues that need to be solved while working with cell pellets instead of solid tissue. Here we describe a simple protocol for the isolation and culture of mesenchymal stem cells from different adult tissues, with applications to stem cell biology and regenerative medicine. Since we are working with population of cells that was obtained after many days of passaging, very efficient and gentle procedures are highly necessary. We demonstrated that our semi-conservative approach regarding to histological techniques and processing of cells for transmission electron microscopy is a well reproducible procedure which results in quality pictures and images of cell populations with minimum distortions and artifacts. We also commented about riskiest steps and histochemical issues (e.g., precise pH, temperature) while preparing the specimen. We bring full and detailed procedures of fixation, post-fixation, infiltration, embedding, polymerization and contrasting of cell obtained from in vitro cell and tissue cultures, with modifications according to our experience. All this steps are essential for us to know more about adult stem cells derived from different sources or about other random cell populations. The knowledge about detailed ultra-structure of adult stem cells cultured in vitro are also essential for their using in regenerative medicine and tissue engineering. PMID:26708176

Bacteriomes of the corn leafhopper, Dalbulus maidis (DeLong & Wolcott, 1923) (Insecta, Hemiptera, Cicadellidae: Deltocephalinae) harbor Sulcia symbiont: molecular characterization, ultrastructure, and transovarial transmission.

Science.gov (United States)

Brentassi, María Eugenia; Franco, Ernesto; Balatti, Pedro; Medina, Rocío; Bernabei, Franco; Marino de Remes Lenicov, Ana M

2017-05-01

In this study, we surveyed the bacteriome-associated microbiota of the corn leafhopper Dalbulus maidis by means of histological, ultrastructural, and molecular analyses. Amplification and sequencing of 16S rDNA genes revealed that the endosymbiont "Candidatus Sulcia muelleri" (Phylum Bacteroidetes) resides in bacteriomes of D. maidis. Phylogenetic analysis showed that the sequence was closely allied to others found in representatives of the subfamily Deltocephalinae. We failed to amplify other sequences as "Candidatus Nasuia deltocephalinicola," a co-primary symbiont frequently associated to deltocephaline leafhoppers. In addition, a metagenetic analysis carried out in order to investigate the presence of other bacteriome-associated bacteria of D. maidis showed that the sequence of Sulcia accounted for 98.56 % of all the sequences. Histological and ultrastructural observations showed that microorganisms harbored in bacteriomes (central syncytium and cytoplasm of uninucleate bacteriocytes) look like others Sulcia described in hemipteran species and they were transovarially transmitted from mother to offspring which is typical of obligate endosymbionts. The only presence of Sulcia in the bacteriomes of D. maidis was discussed.

Ultrastructural and biochemical studies on formation of calcium oxalate in plants

International Nuclear Information System (INIS)

Abdelmottaleb, A.M.

1989-01-01

Plant calcium oxalate crystals occur within cells called crystal idioblasts. Important aspects of this calcification phenomenon have not been characterized. This dissertation examines some of the aspects of this ubiquitous type of calcification including (1) characterization of ultrastructural features of developing crystal idioblasts, (2) determination of the relationship of specialized ultrastructural features of the idioblasts to transport of compounds and mechanisms of crystal deposition, and (3) the biochemical relationship between ascorbic acid metabolism and production of oxalic acid used for crystal formation. Structural and cytochemical studies revealed that crystal idioblasts have dense cytoplasm, modified plastids, enlarged nuclei, extensive endoplasmic reticulum, numerous dictyosomes and vesicles, and a bundle of raphide crystals in their vacuoles. A mechanism for Ca transport and crystal precipitation is proposed, based on these results. There is a strong and dynamic relationship between Ca concentration and oxalic acid produced for crystal formation, where increasing Ca level in the growth medium lead to increased total and insoluble oxalate in the plant. Calmodulin antagonists reduced oxalic acid production

Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates

International Nuclear Information System (INIS)

Rosset, Sabrina; Wiedenmann, Jörg; Reed, Adam J.; D'Angelo, Cecilia

2017-01-01

Enrichment of reef environments with dissolved inorganic nutrients is considered a major threat to the survival of corals living in symbiosis with dinoflagellates (Symbiodinium sp.). We argue, however, that the direct negative effects on the symbiosis are not necessarily caused by the nutrient enrichment itself but by the phosphorus starvation of the algal symbionts that can be caused by skewed nitrogen (N) to phosphorus (P) ratios. We exposed corals to imbalanced N:P ratios in long-term experiments and found that the undersupply of phosphate severely disturbed the symbiosis, indicated by the loss of coral biomass, malfunctioning of algal photosynthesis and bleaching of the corals. In contrast, the corals tolerated an undersupply with nitrogen at high phosphate concentrations without negative effects on symbiont photosynthesis, suggesting a better adaptation to nitrogen limitation. Transmission electron microscopy analysis revealed that the signatures of ultrastructural biomarkers represent versatile tools for the classification of nutrient stress in symbiotic algae. Notably, high N:P ratios in the water were clearly identified by the accumulation of uric acid crystals. - Highlights: • Undersupply with dissolved inorganic phosphate causes coral bleaching. • Ultrastructural biomarkers in algal symbionts identify nutrient stress in reef corals. • Uric acid crystals in zooxanthellae identify high N:P ratios in the water column. • Nitrate enrichment of the water causes phosphate deficiency in Symbiodinium. • Coral symbionts tolerate nitrogen limitation better than phosphorus limitation.

Ultrastructural changes in rabbits liver after irradiation

Energy Technology Data Exchange (ETDEWEB)

Cieciura, L; Bartel, H; Orkisz, S

1975-01-01

Ultrastructural changes in hepatocytes observed 1 to 30 days after irradiation are presented. The dose absorbed was 550 rad (LD 33/30). Electron microscopy studies showed that early and more distinct changes were observed in mitochondria within 24 hours. Disintegration of endoplasmic reticulum and vacuolization of cytoplasm were seen on the 3rd day after irradiation. From the 9th day, the ultrastructural picture of hepatocytes became normal. In the liver in this period the increase in number of large hypertrophic macrophages was noted.

Ultra-Structure database design methodology for managing systems biology data and analyses

Directory of Open Access Journals (Sweden)

Hemminger Bradley M

2009-08-01

Full Text Available Abstract Background Modern, high-throughput biological experiments generate copious, heterogeneous, interconnected data sets. Research is dynamic, with frequently changing protocols, techniques, instruments, and file formats. Because of these factors, systems designed to manage and integrate modern biological data sets often end up as large, unwieldy databases that become difficult to maintain or evolve. The novel rule-based approach of the Ultra-Structure design methodology presents a potential solution to this problem. By representing both data and processes as formal rules within a database, an Ultra-Structure system constitutes a flexible framework that enables users to explicitly store domain knowledge in both a machine- and human-readable form. End users themselves can change the system's capabilities without programmer intervention, simply by altering database contents; no computer code or schemas need be modified. This provides flexibility in adapting to change, and allows integration of disparate, heterogenous data sets within a small core set of database tables, facilitating joint analysis and visualization without becoming unwieldy. Here, we examine the application of Ultra-Structure to our ongoing research program for the integration of large proteomic and genomic data sets (proteogenomic mapping. Results We transitioned our proteogenomic mapping information system from a traditional entity-relationship design to one based on Ultra-Structure. Our system integrates tandem mass spectrum data, genomic annotation sets, and spectrum/peptide mappings, all within a small, general framework implemented within a standard relational database system. General software procedures driven by user-modifiable rules can perform tasks such as logical deduction and location-based computations. The system is not tied specifically to proteogenomic research, but is rather designed to accommodate virtually any kind of biological research. Conclusion We find

Ultrastructural study of chromoplast components rich in glycolipids

OpenAIRE

Wrischer, Mercedes; Prebeg, Tatjana; Magnus, Volker; Ljubešić, Nikola

2001-01-01

A cytochemical method for the ultrastructural localization of glycolipids, performed on thin sections, was used in the study of tubular chromoplasts. The method gave clear pictures of structures that contained glycolipids, while other chemical constituents were not stained. The method was tested on two flowers (Impatients noli-tangere L. and Thunbergia alata Boj. ex Sims) containing different types of tubular chromoplasts. The ultrastructure and mode of development of the two types of tubu...

Evaluation of Dying Vocal Fold Epithelial Cells by Ultrastructural Features and TUNEL Method

Science.gov (United States)

Novaleski, Carolyn K.; Mizuta, Masanobu; Rousseau, Bernard

2016-01-01

Cell death is a regulated mechanism of eliminating cells to maintain tissue homeostasis. This study described two methodological procedures for evaluating cell death in the epithelium of immobilized, approximated, and vibrated vocal folds from 12 New Zealand white breeder rabbits. The gold standard technique of transmission electron microscopy evaluated high-quality ultrastructural criteria of cell death and a common immunohistochemical marker, terminal deoxynucleotidyl transferase dUTP nick end labeling method, to confirm cell death signaling. Results revealed that ultrastructural characteristics of apoptotic cell death, specifically condensed chromatin and apoptotic bodies, were observed after vocal fold vibration and approximation. Although episodes of necrotic cell death were rare, few enlarged cell nuclei were present after vibration and approximation. The vocal fold expresses an immunohistochemical marker for apoptosis along the apical surface of the epithelium. This study provides a solid foundation for future investigations regarding the role of cell death in vocal fold health and disease. PMID:27537846

Ultrastructural observations of target-organs of the crayfish Orconectes limosus exposed to metallic pollutants: application to uranium

International Nuclear Information System (INIS)

Grasset, G.; Simon, O.; Floriani, M.

2004-01-01

Using electron microscopy associated with energy dispersive X-ray microanalysis (EDAXTEM), ultrastructure and elemental analysis in subcellular micro-localization can bring understanding to both metabolic cycle of a metallic pollutant and its potential effects at the subcellular scale. The approach consists in comparing both structures and micro-localization in various tissues/organs ultrathin sections (70-140 nm thickness) obtained from control organisms (i.e. not exposed to a given metal) and exposed organisms. However, the observations of ultrastructural effects of metal exposure involved robust comparison to reference subcellular and cellular organization. Consequently, preliminary developments presented in this poster have been performed from the non-contaminated freshwater crayfish Orconectes limosus (adult at inter-moult state). Studies of ultrastructural images and elemental composition of subcellular mineral deposits were carried out on target organs of uranium accumulation such as the digestive gland, the gills, the intestine and the antennal gland, organs participating in the detoxification, primary accumulation and depuration mechanisms. Observations indicated cell-specific architecture (identification of main organelles, frequency, length of cells), the range of natural variation of the cell organisation between individuals and identification of cellular types. Information will allow then to focus on these identified specific organization after metallic exposure. These ultrastructural observations performed on reference organisms constitute necessarily a first set of data for the cellular metallic effects analysis. (author)

Pathological and ultrastructural analysis of surgical lung biopsies in patients with swine-origin influenza type A/H1N1 and acute respiratory failure

Directory of Open Access Journals (Sweden)

Vera Luiza Capelozzi

2010-01-01

Full Text Available BACKGROUND: Cases of H1N1 and other pulmonary infections evolve to acute respiratory failure and death when co-infections or lung injury predominate over the immune response, thus requiring early diagnosis to improve treatment. OBJECTIVE: To perform a detailed histopathological analysis of the open lung biopsy specimens from five patients with ARDS with confirmed H1N1. METHODS: Lung specimens underwent microbiologic analysis, and examination by optical and electron microscopy. Immunophenotyping was used to characterize macrophages, natural killer, T and B cells, and expression of cytokines and iNOS. RESULTS: The pathological features observed were necrotizing bronchiolitis, diffuse alveolar damage, alveolar hemorrhage and abnormal immune response. Ultrastructural analysis showed viral-like particles in all cases. CONCLUSIONS: Viral-like particles can be successfully demonstrated in lung tissue by ultrastructural examination, without confirmation of the virus by RT-PCR on nasopharyngeal aspirates. Bronchioles and epithelium, rather than endothelium, are probably the primary target of infection, and diffuse alveolar damage the consequence of the effect of airways obliteration and dysfunction on innate immunity, suggesting that treatment should be focused on epithelial repair.

Ultrastructural changes of cell walls under intense mechanical treatment of selective plant raw material

International Nuclear Information System (INIS)

Bychkov, Aleksey L.; Ryabchikova, E.I.; Korolev, K.G.; Lomovsky, O.I.

2012-01-01

Structural changes of cell walls under intense mechanical treatment of corn straw and oil-palm fibers were studied by electron and light microscopy. Differences in the character of destruction of plant biomass were revealed, and the dependence of destruction mechanisms on the structure of cell walls and lignin content was demonstrated. We suggest that the high reactivity of the particles of corn straw (about 18% of lignin) after intense mechanical treatment is related to disordering of cell walls and an increase of the surface area, while in the case of oil palm (10% of lignin) the major contribution into an increase in the reactivity is made by an increase of surface area. -- Highlights: ► Structure of cell walls determines the processes of plant materials' destruction. ► Ultrastructure of highly lignified materials strongly disordering by mechanical action. ► Ultrastructure of low-lignified materials is not disordering by mechanical action.

Pathology of mitochondria in MELAS syndrome: an ultrastructural study.

Science.gov (United States)

Felczak, Paulina; Lewandowska, Eliza; Stępniak, Iwona; Ołdak, Monika; Pollak, Agnieszka; Lechowicz, Urszula; Pasennik, Elżbieta; Stępień, Tomasz; Wierzba-Bobrowicz, Teresa

Ultrastructural changes in skeletal muscle biopsy in a 24-year-old female patient with clinically suspected mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes (MELAS) syndrome are presented. We observed proliferation and/or pleomorphism of mitochondria in skeletal muscle and smooth muscle cells of arterioles, as well as in pericytes of capillaries. Paracrystalline inclusions were found only in damaged mitochondria of skeletal muscle. Genetic testing revealed a point mutation in A3243G tRNALeu(UUR) typical for MELAS syndrome. We conclude that differentiated pathological changes of mitochondria in the studied types of cells may be associated with the different energy requirements of these cells.

Ultrastructure of a hexagonal array in exosporium of a highly sporogenic mutant of Clostridium botulinum type A revealed by electron microscopy using optical diffraction and filtration.

Science.gov (United States)

Masuda, K; Kawata, T; Takumi, K; Kinouchi, T

1980-01-01

The ultrastructure of a hexagonal array in the exosporium from spores of a highly sporogenic mutant of Clostridium botulinum type A strain 190L was studied by electron microscopy of negatively stained exosporium fragments using optical diffraction and filtration. The exosporium was composed of three or more lamellae showing and equilateral, hexagonal periodicity. Images of the single exosporium layer from which the noise had been filtered optically revealed that the hexagonally arranged, morphological unit of the exosporium was composed of three globular subunits about 2.1 nm in diameter which were arranged at the vertices of an equilateral triangle with sides of about 2.4 nm. The morphological units were arranged with a spacing of about 4.5 nm. the adjacent globular subunits appeared to be interconnected by delicate linkers.

Collyricloides massanae (Digenea, Collyriclidae: spermatozoon ultrastructure and phylogenetic importance

Directory of Open Access Journals (Sweden)

Bakhoum Abdoulaye Jacque

2014-01-01

Full Text Available The spermatological characteristics of Collyricloides massanae (Digenea: Collyriclidae, a parasite of Apodemus sylvaticus caught in France, were studied by means of transmission electron microscopy. The mature sperm of C. massanae presents two axonemes of different lengths with the 9 + “1” pattern of the Trepaxonemata, two bundles of parallel cortical microtubules, external ornamentation of the plasma membrane, spine-like bodies, one mitochondrion, a nucleus and granules of glycogen. An analysis of spermatological organisation emphasised some differences between the mature spermatozoon of C. massanae and those reported in the Gorgoderoidea species studied to date, specially belonging to the families Dicrocoeliidae, Paragonimidae and Troglotrematidae. The ultrastructural criteria described in C. massanae such as the morphology of both anterior and posterior spermatozoon extremities, the association “external ornamentation + cortical microtubules”, the type 2 of external ornamentation and the spine-like bodies would allow us to bring closer the Collyriclidae to Microphalloidea. However, further ultrastructural and molecular studies are needed particularly in the unexplored taxa in order to fully resolve the phylogenetic position of the Collyriclidae.

[Ultrastructural and morphological peculiarities of Turbellariae Bothrioplana semperi and the problem of monophilia of Seriata (Platyhelmimthes, Turbellaria)].

Science.gov (United States)

Kornakova, E E

2012-01-01

The ultrastructure and morphogenesis of rhabdites as well as the morphology of pharynx walls in Bothrioplana semperi (Turbellaria, Bothrioplanidae) are described. The ultrastructure of rhabdites and their morphogenesis in this species are close to those in Macrostomida (Turbellaria Archoophora). The order of muscle layers in the pharynx walls of Bothrioplana semperi makes it similar to Tricladida Maricola and some Tricladida Paludicola and Terricola. The analysis of ultrastructural and morphological characters in Bothrioplana semperi as compared to those in Turbellaria Proseriata and Tricladida is provided. It is shown that relation of apomorphic and plesiomorphic characters in the phyla analyzed corresponds the most to the viewpoint about the early divergence of these groups from early Turbellaria Neoophora. In this case Proseriata and Tricladida are not sister groups, while Bothrioplanidae should be regarded as a sister group to the ancestors of Tricladida and, possibly, Neodermata.

Ultrastructural characteristics of spermatogenesis in Pallas's mastiff bat, Molossus molossus (Chiroptera: Molossidae).

Science.gov (United States)

Beguelini, Mateus R; Taboga, Sebastião R; Morielle-Versute, Eliana

2012-07-01

Despite the large number of species, their wide distribution, and unique reproductive characteristics, Neotropical bats have been poorly studied, and important aspects of the reproduction of these animals have not been elucidated. We made an ultrastructural analysis of spermatogenesis in Molossus molossus (Molossidae). The process of spermatogonial differentiation is similar to that found in other bats and is also relatively similar to that of Primates, with three main spermatogonia types: A(d), A(p), and B. Meiotic divisions proceed similarly to those of most mammals, and spermiogenesis is clearly divided into 12 steps, in the middle of the range known for bats (9-16 steps). Formation of the acrosome is similar to that known from other mammals; however, the ultrastructure of spermatozoa was found to have unique characteristics, including many wavy acrosomal projections on its surface, which seems to be specific for the family Molossidae. Comparing the ultrastructure of the spermatozoon of M. molossus with other bats already study, we observed that three characters vary: morphology of the outer dense fibers, of the perforatorium, and of the spermatozoon head. The great similarity of morphological characters between M. molossus and Platyrrhinus lineatus suggests that M. molossus is more closely related to the Phyllostomidae than to the Rhinolophidae and the Vespertilionidae. Copyright © 2012 Wiley Periodicals, Inc.

Ultrastructural hepatocellular features associated with severe hepatic lipidosis in cats.

Science.gov (United States)

Center, S A; Guida, L; Zanelli, M J; Dougherty, E; Cummings, J; King, J

1993-05-01

In this study, we compared hepatic ultrastructure in healthy cats, in cats with severe hepatic lipidosis, and in cats with experimentally induced, chronic, extrahepatic bile duct occlusion. Ultrastructural features unique to the lipidosis syndrome included an apparent reduction in number of peroxisomes and alteration in their morphologic features. The quantity of endoplasmic reticulum, Golgi complexes, and lysosomes was subjectively reduced, and paucity of cytosolic glycogen was observed. Bile canaliculi appeared collapsed because of cytosolic distention with lipid. Mitochondria were reduced in number and were markedly pleomorphic. Cristae assumed a variety of shapes, lengths, and orientations. Ultrastructural features of bile duct occlusion were similar to those described in other species and differed from those in cats with hepatic lipidosis.

Ultrastructural features of the internodes’ surface in horsetail (Equisetum arvense L.

Directory of Open Access Journals (Sweden)

Myroslava Stakhiv

2013-04-01

Full Text Available The ultrastructure of the outer surface of the common horsetail stem was studied. Through electron microscopic analysis we showed that silica plates on the surface of Equisetum arvense L. stem are distributed evenly, not tight, in thin layer. Thus, compact arrangement of particles on the internodes causes high mechanical strength and stiffness of the E. arvensestem and lateral branches.

Autophagy as an ultrastructural marker of heavy metal toxicity in human cord blood hematopoietic stem cells

International Nuclear Information System (INIS)

Di Gioacchino, Mario; Petrarca, Claudia; Perrone, Angela; Farina, Massimo; Sabbioni, Enrico; Hartung, Thomas; Martino, Simone; Esposito, Diana L.; Lotti, Lavinia Vittoria; Mariani-Costantini, Renato

2008-01-01

Stem cells are a key target of environmental toxicants, but little is known about their toxicological responses. We aimed at developing an in-vitro model based on adult human stem cells to identify biomarkers of heavy metal exposure. To this end we investigated the responses of human CD34+ hematopoietic progenitor cells to hexavalent chromium (Cr[VI]) and cadmium (Cd). Parallel cultures of CD34+ cells isolated from umbilical cord blood were exposed for 48 h to 0.1 μM and 10 μM Cr(VI) or Cd. Cultures treated with 10 μM Cr(VI) or Cd showed marked cell loss. Ultrastructural analysis of surviving cells revealed prominent autophagosomes/autophagolysosomes, which is diagnostic of autophagy, associated with mitochondrial damage and replication, dilatation of the rough endoplasmic reticulum and Golgi complex, cytoplasmic lipid droplets and chromatin condensation. Treated cells did not show the morphologic hallmarks of apoptosis. Treatment with 0.1 μM Cr(VI) or Cd did not result in cell loss, but at the ultrastructural level cells showed dilated endoplasmic reticulum and evidence of mitochondrial damage. We conclude that autophagy is implicated in the response of human hematopoietic stem cells to toxic concentrations of Cr(VI) and Cd. Autophagy, which mediates cell survival and death under stress, deserves further evaluation to be established as biomarker of metal exposure

Autophagy as an ultrastructural marker of heavy metal toxicity in human cord blood hematopoietic stem cells

Energy Technology Data Exchange (ETDEWEB)

Di Gioacchino, Mario [Aging Research Center, ' G. d' Annunzio' University Foundation, Via Colle dell' Ara, 66100 Chieti (Italy); Medicine and Science of Ageing University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy)], E-mail: m.digioacchino@unich.it; Petrarca, Claudia; Perrone, Angela [Aging Research Center, ' G. d' Annunzio' University Foundation, Via Colle dell' Ara, 66100 Chieti (Italy); Medicine and Science of Ageing University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy); Farina, Massimo; Sabbioni, Enrico; Hartung, Thomas [Oncology and Neurosciences University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy); Martino, Simone [Department of Experimental Medicine, University La Sapienza, Viale Regina Elena 324, 00161 Rome (Italy); Esposito, Diana L. [Aging Research Center, ' G. d' Annunzio' University Foundation, Via Colle dell' Ara, 66100 Chieti (Italy); Oncology and Neurosciences University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy); Lotti, Lavinia Vittoria [Department of Experimental Medicine, University La Sapienza, Viale Regina Elena 324, 00161 Rome (Italy); Mariani-Costantini, Renato [Aging Research Center, ' G. d' Annunzio' University Foundation, Via Colle dell' Ara, 66100 Chieti (Italy); Oncology and Neurosciences University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy)

2008-03-15

Stem cells are a key target of environmental toxicants, but little is known about their toxicological responses. We aimed at developing an in-vitro model based on adult human stem cells to identify biomarkers of heavy metal exposure. To this end we investigated the responses of human CD34+ hematopoietic progenitor cells to hexavalent chromium (Cr[VI]) and cadmium (Cd). Parallel cultures of CD34+ cells isolated from umbilical cord blood were exposed for 48 h to 0.1 {mu}M and 10 {mu}M Cr(VI) or Cd. Cultures treated with 10 {mu}M Cr(VI) or Cd showed marked cell loss. Ultrastructural analysis of surviving cells revealed prominent autophagosomes/autophagolysosomes, which is diagnostic of autophagy, associated with mitochondrial damage and replication, dilatation of the rough endoplasmic reticulum and Golgi complex, cytoplasmic lipid droplets and chromatin condensation. Treated cells did not show the morphologic hallmarks of apoptosis. Treatment with 0.1 {mu}M Cr(VI) or Cd did not result in cell loss, but at the ultrastructural level cells showed dilated endoplasmic reticulum and evidence of mitochondrial damage. We conclude that autophagy is implicated in the response of human hematopoietic stem cells to toxic concentrations of Cr(VI) and Cd. Autophagy, which mediates cell survival and death under stress, deserves further evaluation to be established as biomarker of metal exposure.

Early studies of placental ultrastructure by electron microscopy

DEFF Research Database (Denmark)

Carter, A M; Enders, A C

2016-01-01

many other scientists to Washington University in St. Louis. Work on human placental ultrastructure was initiated at Cambridge and Kyoto whilst domestic animals were initially studied by Björkman in Stockholm and electron micrographs of bat placenta were published by Wimsatt of Cornell University......BACKGROUND: Transmission electron microscopy (TEM) was first applied to study placental ultrastructure in the 1950's. We review those early studies and mention the scientists that employed or encouraged the use of TEM. FINDINGS: Among the pioneers Edward W. Dempsey was a key figure who attracted...

Histology and ultrastructure of the integumental chromatophores in tokay gecko (Gekko gecko) (Linnaeus, 1758) skin

OpenAIRE

Szyd?owski, Pawe?; Madej, Jan Pawe?; Mazurkiewicz-Kania, Marta

2017-01-01

This paper describes the relationship between the arrangement of dermal chromatophores in tokay gecko (Gekko gecko) skin and the formation of wild-type colouration, with emphasis on the ultrastructure of chromatophores. The samples of the tokay gecko skin were collected from wild-type colouration adult specimens. Morphology and distribution of chromatophores was determined by using light microscopy and transmission electron microscopy. The present study revealed that orange/red coloured skin ...

3-D Cellular Ultrastructure Can Be Resolved by X-ray Microscopy | Center for Cancer Research

Science.gov (United States)

X-ray microscopy (XRM) is more rapid than cryoelectron tomography or super-resolution fluorescence microscopy and could fill an important gap in current technologies used to investigate in situ three-dimensional structure of cells. New XRM methods developed by first author Gerd Schneider, Ph.D., working with James McNally. Ph.D., and a team of colleagues, is capable of revealing full cellular ultrastructure without requiring fixation, staining, or sectioning.

Electron tomography and cryo-SEM characterization reveals novel ultrastructural features of host-parasite interaction during Chlamydia abortus infection.

Science.gov (United States)

Wilkat, M; Herdoiza, E; Forsbach-Birk, V; Walther, P; Essig, A

2014-08-01

Chlamydia (C.) abortus is a widely spread pathogen among ruminants that can be transmitted to women during pregnancy leading to severe systemic infection with consecutive abortion. As a member of the Chlamydiaceae, C. abortus shares the characteristic feature of an obligate intracellular biphasic developmental cycle with two morphological forms including elementary bodies (EBs) and reticulate bodies (RBs). In contrast to other chlamydial species, C. abortus ultrastructure has not been investigated yet. To do so, samples were fixed by high-pressure freezing and processed by different electron microscopic methods. Freeze-substituted samples were analysed by transmission electron microscopy, scanning transmission electron microscopical tomography and immuno-electron microscopy, and freeze-fractured samples were analysed by cryo-scanning electron microscopy. Here, we present three ultrastructural features of C. abortus that have not been reported up to now. Firstly, the morphological evidence that C. abortus is equipped with the type three secretion system. Secondly, the accumulation and even coating of whole inclusion bodies by membrane complexes consisting of multiple closely adjacent membranes which seems to be a C. abortus specific feature. Thirdly, the formation of small vesicles in the periplasmic space of RBs in the second half of the developmental cycle. Concerning the time point of their formation and the fact that they harbour chlamydial components, these vesicles might be morphological correlates of an intermediate step during the process of redifferentiation of RBs into EBs. As this feature has also been shown for C. trachomatis and C. pneumoniae, it might be a common characteristic of the family of Chlamydiaceae.

Ultrastructural diversity between centrioles of eukaryotes.

Science.gov (United States)

Gupta, Akshari; Kitagawa, Daiju

2018-02-16

Several decades of centriole research have revealed the beautiful symmetry present in these microtubule-based organelles, which are required to form centrosomes, cilia, and flagella in many eukaryotes. Centriole architecture is largely conserved across most organisms, however, individual centriolar features such as the central cartwheel or microtubule walls exhibit considerable variability when examined with finer resolution. Here, we review the ultrastructural characteristics of centrioles in commonly studied organisms, highlighting the subtle and not-so-subtle differences between specific structural components of these centrioles. Additionally, we survey some non-canonical centriole structures that have been discovered in various species, from the coaxial bicentrioles of protists and lower land plants to the giant irregular centrioles of the fungus gnat Sciara. Finally, we speculate on the functional significance of these differences between centrioles, and the contribution of individual structural elements such as the cartwheel or microtubules towards the stability of centrioles.Centriole structure, cartwheel, triplet microtubules, SAS-6, centrosome.

Pancreatic involvement in co-infection visceral leishmaniasis and HIV: histological and ultrastructural aspects

Directory of Open Access Journals (Sweden)

CHEHTER Ethel Zimberg

2001-01-01

Full Text Available The involvement of the gastrointestinal tract in the co-infection of HIV and Leishmania is rarely reported. We report the case of an HIV-infected adult man co-infected with a disseminated form of leishmaniasis involving the liver, lymph nodes, spleen and, as a feature reported for the first time in the English literature, the pancreas. Light microscopy showed amastigote forms of Leishmania in pancreatic macrophages and immunohistochemical staining revealed antigens for Leishmania and also for HIV p24. Microscopic and ultrastructural analysis revealed severe acinar atrophy, decreased zymogen granules in the acinar cytoplasm and also nuclear abnormalities such as pyknosis, hyperchromatism and thickened chromatin. These findings might correspond to the histologic pattern of protein-energy malnutrition in the pancreas as shown in our previous study in pancreas with AIDS and no Leishmania. In this particular case, the protein-energy malnutrition may be due to cirrhosis, or, Leishmania or HIV infection or all mixed. We believe that this case represents the morphologic substratum of the protein energy malnutrition in pancreas induced by the HIV infection. Further studies are needed to elucidate these issues.

Ultrastructural characteristics of three undifferentiated mouse embryonic stem cell lines and their differentiated three-dimensional derivatives: a comparative study.

Science.gov (United States)

Alharbi, Suzan; Elsafadi, Mona; Mobarak, Mohammed; Alrwili, Ali; Vishnubalaji, Radhakrishnan; Manikandan, Muthurangan; Al-Qudsi, Fatma; Karim, Saleh; Al-Nabaheen, May; Aldahmash, Abdullah; Mahmood, Amer

2014-04-01

The fine structures of mouse embryonic stem cells (mESCs) grown as colonies and differentiated in three-dimensional (3D) culture as embryoid bodies (EBs) were analyzed by transmission electron microscopy. Undifferentiated mESCs expressed markers that proved their pluripotency. Differentiated EBs expressed different differentiation marker proteins from the three germ layers. The ultrastructure of mESCs revealed the presence of microvilli on the cell surfaces, large and deep infolded nuclei, low cytoplasm-to-nuclear ratios, frequent lipid droplets, nonprominent Golgi apparatus, and smooth endoplasmic reticulum. In addition, we found prominent juvenile mitochondria and free ribosomes-rich cytoplasm in mESCs. Ultrastructure of the differentiated mESCs as EBs showed different cell arrangements, which indicate the different stages of EB development and differentiation. The morphologies of BALB/c and 129 W9.5 EBs were very similar at day 4, whereas C57BL/6 EBs were distinct from the others at day 4. This finding suggested that differentiation of EBs from different cell lines occurs in the same pattern but not at the same rate. Conversely, the ultrastructure results of BALB/c and 129 W9.5 ESCs revealed differentiating features, such as the dilated profile of a rough endoplasmic reticulum. In addition, we found low expression levels of undifferentiated markers on the outer cells of BALB/c and 129 W9.5 mESC colonies, which suggests a faster differentiation potential.

Grape juice concentrate (G8000(®) ) intake mitigates testicular morphological and ultrastructural damage following cadmium intoxication.

Science.gov (United States)

Lamas, Celina A; Gollücke, Andrea P B; Dolder, Heidi

2015-10-01

Cadmium is a well-known testicular toxicant, and parts of the world population are exposed chronically by inhalation or by food and water intake. Grape products have been highlighted as important sources of bioactive compounds, having anti-inflammatory, anti-oxidant and metal chelating properties. Since maintenance of tissue morphology is essential for testicular sperm development and hence male fertility, we analysed the protective effect of grape juice concentrate (GJC) (G8000(®) ) consumption on testicular morphology in rats exposed to cadmium. Thus, four groups of male Wistar rats (n = 6 per group), 50 days old, ingested either water or G8000(®) (2 g/kg/day) until they had completed one spermatogenic cycle in adult life (136 days old). Cadmium (1.2 mg / kg) was injected intraperitoneally when the animals were 80 days old into one of the water and one of the G8000 groups; intraperitoneal saline was used as a control in the other two groups. Animals anaesthetised and exsanguinated at 136 days and then perfused with Karnovsky's fixative and then the testes were collected for morphological analysis. We describe evident disruption of testicular morphology by cadmium, with alteration in tissue component proportions, reduced Leydig cells volume and initial signs of an inflammatory process. Ultrastructural analysis showed greater damage, suggesting spermatogenesis disruption. G8000(®) ingestion allowed tissue architecture to be re-established, as was corroborated by our stereological and morphometric findings. Animals from the group where G8000(®) had been administered together with cadmium revealed a significant reduction in macrophages and blood vessel volume, suggesting diminished inflammation, when compared to animals that received only cadmium. Moreover, smaller number of ultrastructural alterations was noted, revealing fewer areas of degeneration and disorganized interstitium. In conclusion, our results demonstrate that GJC consumption prevented the

Acinar cell ultrastructure after taurine treatment in rat acute necrotizing pancreatitis

International Nuclear Information System (INIS)

Ates, Y.; Mas, M. R.; Taski, I.; Comert, B.; Isik, A. T.; Mas, N. M.; Yener, N.

2006-01-01

To evaluate the organelle-based changes in acinar cells in experimental acute necrotizing pancreatitis (ANP) after taurine treatment and the association of electron microscopic findings with histopathalogical changes and oxidative stress markers. The study was performed in February 2005at Gulhane School of Medicine and Hacettepe University, Turkey. Forty-five rats were divided into 3 groups. Acute necrotizing pancreatitis was induced in groups II and III. Groups I and II were treated with saline and Group III with taurine 1000mg/kg/day, i.p, for 48 hours. Histopathological and ultrastructural examinations were determined using one-way analysis of variance and Kruskal-Wallis tests. Histopathologic findings improved significantly after taurine treatment. Degree of injury in rough and smooth endoplasmic reticulums, Golgi apparatus, mitochondria and nucleus of acinar cells also decreased with taurine in correlation with biochemical and histological results. Taurine improves acinar cell organelle structure, and ultrastructural recovery in ANP reflects histological improvement. (author)

Ultrastructural analysis of anastomosis group 9 of Rhizoctonia solani

International Nuclear Information System (INIS)

Cedeno, L; Palacios Pru, E

1996-01-01

The ultrastructure of R. solani AG-9 (S-21, ATCC 62804) was investigated with transmission electron microscopy (TEM). The most important characteristics were those related with cell wall thickness, cytoplasmic matrix composition, number of nuclei and nucleoli and secretory material production. The majority of examined hyphae showed lateral cell walls thinner than those recorded before. The cytoplasmic matrix consistently appeared differentiated into two classes, one formed by a highly electron dense granular fine material and the other one showing a coloidal substance of very low density which give these cells a 'tiger-like' aspect. The granular dense matrix always had abundant free ribosomes and usually surrounded the cytoplasmic organelles and the septal pore apparatus. The somatic cells showed up to 5 nuclei, some of which with three nucleoli. Masses of secretory material surrounded by membrane were regularly seen in the cytoplasm, with sizes similar to those of nuclei

Value of transmission electron microscopy for primary ciliary dyskinesia diagnosis in the era of molecular medicine: Genetic defects with normal and non-diagnostic ciliary ultrastructure.

Science.gov (United States)

Shapiro, Adam J; Leigh, Margaret W

2017-01-01

Primary ciliary dyskinesia (PCD) is a genetic disorder causing chronic oto-sino-pulmonary disease. No single diagnostic test will detect all PCD cases. Transmission electron microscopy (TEM) of respiratory cilia was previously considered the gold standard diagnostic test for PCD, but 30% of all PCD cases have either normal ciliary ultrastructure or subtle changes which are non-diagnostic. These cases are identified through alternate diagnostic tests, including nasal nitric oxide measurement, high-speed videomicroscopy analysis, immunofluorescent staining of axonemal proteins, and/or mutation analysis of various PCD causing genes. Autosomal recessive mutations in DNAH11 and HYDIN produce normal TEM ciliary ultrastructure, while mutations in genes encoding for radial spoke head proteins result in some cross-sections with non-diagnostic alterations in the central apparatus interspersed with normal ciliary cross-sections. Mutations in nexin link and dynein regulatory complex genes lead to a collection of different ciliary ultrastructures; mutations in CCDC65, CCDC164, and GAS8 produce normal ciliary ultrastructure, while mutations in CCDC39 and CCDC40 cause absent inner dynein arms and microtubule disorganization in some ciliary cross-sections. Mutations in CCNO and MCIDAS cause near complete absence of respiratory cilia due to defects in generation of multiple cellular basal bodies; however, the scant cilia generated may have normal ultrastructure. Lastly, a syndromic form of PCD with retinal degeneration results in normal ciliary ultrastructure through mutations in the RPGR gene. Clinicians must be aware of these genetic causes of PCD resulting in non-diagnostic TEM ciliary ultrastructure and refrain from using TEM of respiratory cilia as a test to rule out PCD.

Ultrastructural Analysis of Human Breast Cancer Cells during Their Overtime Interaction with Cerium Oxide Nanoparticles

KAUST Repository

AlAbbadi, Shatha H.

2016-12-01

Cerium oxide nanoparticles have been proposed as an anticancer agent, thanks to their ability of tuning the redox activity in accordance to different conditions, which lead to selective roles on healthy and cancer cells. Recent evidence suggested the ability of these nanoparticles to be toxic against cancer cells, while confer protection from oxidative stress, toward healthy cells. The main focus of this study was to determine the ultrastructural effects of cerium oxide nanoparticles over multiple incubation time of 1, 3, and 7 days on breast healthy and cancer cells. Cellular characterizations were carried out using electron microscopes, both transmission and scanning electron microscopes, while the viability assessments were performed by propidium iodide and trypan blue viability assays. The obtained results of the viability assays and electron microscopy suggested higher toxic effects on the cancer cell line viability by using a nanoceria dose of 300 μg/mL after 1 day of treatment. Such effects were shown to be preserved at 3 days, and in a longer time point of 7 days. On the contrary, the healthy cells underwent less effects on their viability at time point of 1 and 7 days. The 3 days treatment demonstrated a reduction on the number of cells that did not correlate with an increase of the dead cells, which suggested a possible initial decrease of the cell growth rate, which could be due to the high intracellular loading of nanoparticles. To conclude, the overall result of this experiment suggested that 300 μg/mL of CeO2 nanoparticles is the most suitable dose, within the range and the time point tested, which induces long-lasting cytotoxic effects in breast cancer cells, without harming the normal cells, as highlighted by the viability assays and ultrastructural characterization of electron microscopy analysis.

Loss of Sleep Affects the Ultrastructure of Pyramidal Neurons in the Adolescent Mouse Frontal Cortex.

Science.gov (United States)

de Vivo, Luisa; Nelson, Aaron B; Bellesi, Michele; Noguti, Juliana; Tononi, Giulio; Cirelli, Chiara

2016-04-01

The adolescent brain may be uniquely affected by acute sleep deprivation (ASD) and chronic sleep restriction (CSR), but direct evidence is lacking. We used electron microscopy to examine how ASD and CSR affect pyramidal neurons in the frontal cortex of adolescent mice, focusing on mitochondria, endosomes, and lysosomes that together perform most basic cellular functions, from nutrient intake to prevention of cellular stress. Adolescent (1-mo-old) mice slept (S) or were sleep deprived (ASD, with novel objects and running wheels) during the first 6-8 h of the light period, chronically sleep restricted (CSR) for > 4 days (using novel objects, running wheels, social interaction, forced locomotion, caffeinated water), or allowed to recover sleep (RS) for ∼32 h after CSR. Ultrastructural analysis of 350 pyramidal neurons was performed (S = 82; ASD = 86; CSR = 103; RS = 79; 4 to 5 mice/group). Several ultrastructural parameters differed in S versus ASD, S versus CSR, CSR versus RS, and S versus RS, although the different methods used to enforce wake may have contributed to some of the differences between short and long sleep loss. Differences included larger cytoplasmic area occupied by mitochondria in CSR versus S, and higher number of secondary lysosomes in CSR versus S and RS. We also found that sleep loss may unmask interindividual differences not obvious during baseline sleep. Moreover, using a combination of 11 ultrastructural parameters, we could predict in up to 80% of cases whether sleep or wake occurred at the single cell level. Ultrastructural analysis may be a powerful tool to identify which cellular organelles, and thus which cellular functions, are most affected by sleep and sleep loss. © 2016 Associated Professional Sleep Societies, LLC.

Effects of Selected Egyptian Honeys on the Cellular Ultrastructure and the Gene Expression Profile of Escherichia coli.

Directory of Open Access Journals (Sweden)

Reham Wasfi

Full Text Available The purpose of this study was to: (i evaluate the antibacterial activities of three Egyptian honeys collected from different floral sources (namely, citrus, clover, and marjoram against Escherichia coli; (ii investigate the effects of these honeys on bacterial ultrastructure; and (iii assess the anti-virulence potential of these honeys, by examining their impacts on the expression of eight selected genes (involved in biofilm formation, quorum sensing, and stress survival in the test organism. The minimum inhibitory concentration (MIC of the honey samples against E. coli ATCC 8739 were assessed by the broth microdilution assay in the presence and absence of catalase enzyme. Impacts of the honeys on the cellular ultrastructure and the expression profiles of the selected genes of E. coli were examined using transmission electron microscopy (TEM and quantitative real-time polymerase chain reaction (qPCR analysis, respectively. The susceptibility tests showed promising antibacterial activities of all the tested honeys against E. coli. This was supported by the TEM observations, which revealed "ghost" cells lacking DNA, in addition to cells with increased vacuoles, and/or with irregular shrunken cytoplasm. Among the tested honeys, marjoram exhibited the highest total antibacterial activity and the highest levels of peroxide-dependent activity. The qPCR analysis showed that all honey-treated cells share a similar overall pattern of gene expression, with a trend toward reduced expression of the virulence genes of interest. Our results indicate that some varieties of the Egyptian honey have the potential to be effective inhibitor and virulence modulator of E. coli via multiple molecular targets.

The ultrastructural alterations in rat corneas with experimentally-induced diabetes mellitus

International Nuclear Information System (INIS)

Take, G.; Karabay, G.; Erdogan, D.; Duyar, I.

2006-01-01

To examine the ultrastructural changes of rat corneas in streptozotocin (STZ) induced diabetes mellitus and the and the follow-up insulin treatment. Sprague-Dawley type rats were used for experimental procedures during the period from January to April 2003 at Baskent University, Ankara, Turkey. Rats were studied in four groups: group 1: controls, group 2 sham controls (single dose IV sodium citrate); group 3 STZ-induced diabetes mellitus (Single dose 45mg/kg STZ intravenously), group 4: diabetes mellitus + insulin treatment (8U/day). We observed degenerative changes in the epithelial layer, stromal keratocytes and endothelial cells in diabetic group. In contrast, the corneal layers have revealed positive alterations in the insulin-treated group. The statistical analysis, showed significant narrowing in the epithelial layer in the diabetic group (p0.02), whereas thickening was observed in the epithelial basement membrane and Descemet's membrane (p=0.002). It was determined that that diabetes mellitus causes degenerative changes in cornea, which are positively influenced by short-term insulin treatment. (author)

Ultrastructural studies of Biomphalaria glabrata (Say, 1818) embryo

International Nuclear Information System (INIS)

Kikuchi, O.K.; Okazaki, K.; Kawano, T.; Ribeiro, A.A.G.F.C.

1988-09-01

Ultrastructural studies of Biomphalaria glabrata embryos (MOllusca: Gastropoda), and important snail vector of schistosomiasis has not been explored. In the present work it was evaluated a suitable electron microscopical technique for embryos processing. Promising results was obtained with double fixation in 1% glutaraldehyde plus 1% osmium tetroxide in 0.05 M cacodylate buffer (pH 7.4), preliminary staining overnight in 1% uranyl acetate and embedding in EPON or Polylite under vacuum. It was used embryos at young trochophore stage wich is characterized by active organogenesis. Some ultrastructural aspects of B. glabrata embryos cells are presented. (author) [pt

Nanoscopic and Photonic Ultrastructural Characterization of Two Distinct Insulin Amyloid States

Directory of Open Access Journals (Sweden)

Mikael Lindgren

2012-02-01

Full Text Available Two different conformational isoforms or amyloid strains of insulin with different cytotoxic capacity have been described previously. Herein these filamentous and fibrillar amyloid states of insulin were investigated using biophysical and spectroscopic techniques in combination with luminescent conjugated oligothiophenes (LCO. This new class of fluorescent probes has a well defined molecular structure with a distinct number of thiophene units that can adopt different dihedral angles depending on its binding site to an amyloid structure. Based on data from surface charge, hydrophobicity, fluorescence spectroscopy and imaging, along with atomic force microscopy (AFM, we deduce the ultrastructure and fluorescent properties of LCO stained insulin fibrils and filaments. Combined total internal reflection fluorescence microscopy (TIRFM and AFM revealed rigid linear fibrous assemblies of fibrils whereas filaments showed a short curvilinear morphology which assemble into cloudy deposits. All studied LCOs bound to the filaments afforded more blue-shifted excitation and emission spectra in contrast to those corresponding to the fibril indicating a different LCO binding site, which was also supported by less efficient hydrophobic probe binding. Taken together, the multi-tool approach used here indicates the power of ultrastructure identification applying AFM together with LCO fluorescence interrogation, including TIRFM, to resolve structural differences between amyloid states.

Atrial natriuretic peptide (ANP)-granules: ultrastructure ...

African Journals Online (AJOL)

ANP) are present in the four regions of the atrial-auricular complex (two atria and two auricles). ANP-immunoreactivity was detected in all granules from the four regions. Ultrastructurally, atrial myocytes show the presence of very electron dense ...

Effect of Electrocautery on Endothelial Integrity of the Internal Thoracic Artery: Ultrastructural Analysis with Transmission Electron Microscopy

OpenAIRE

Onan, Burak; Yeniterzi, Mehmet; Onan, Ismihan Selen; Ersoy, Burak; Gonca, Suheyla; Gelenli, Elif; Solakoglu, Seyhun; Bakir, Ihsan

2014-01-01

The internal thoracic artery (ITA) is typically harvested from the chest wall by means of conventional electrocautery. We investigated the effects of electrocautery on endothelial-cell and vessel-wall morphology at the ultrastructural level during ITA harvesting.

Effects of hydrogen peroxide bleaching strips on tooth surface color, surface microhardness, surface and subsurface ultrastructure, and microchemical (Raman spectroscopic) composition.

Science.gov (United States)

Duschner, Heinz; Götz, Hermann; White, Donald J; Kozak, Kathleen M; Zoladz, James R

2006-01-01

This study examined the effects of hydrogen peroxide tooth bleaching strips on the surface hardness and morphology of enamel and the ultrastructure and chemical composition of enamel and dentin in vitro. Sound human molars were ground and polished to prepare a uniform substrate for bleaching treatments. A cycling treatment methodology was employed which alternated ex vivo human salivary exposures with bleaching treatments under conditions of controlled temperature and durations of treatment. Bleaching treatments included commercial Crest Whitestrips bleaching strips, which utilize hydrogen peroxide in a gel as the in situ bleaching source at 6.0 and 6.5% concentrations of H2O2. Control treatments included an untreated group. Crest Whitestrips bleaching included treatment exposures simulating 2x the recommended clinical exposures (28 hours bleaching). Surface color measurements were taken prior to and following bleaching to ensure tooth bleaching activity. The effects of bleach on physical properties of enamel were assessed with microhardness measures. Ultrastructural effects were classified by surface and subsurface confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) techniques. In addition, the effects of bleaching on tooth microchemical composition was studied in different tooth regions by coincident assessment of Raman spectroscopic signature. Color assessments confirmed significant ex vivo tooth bleaching by Whitestrips. Surface microhardness and SEM measures revealed no deleterious effects on the enamel surfaces. CLSM micromorphological assessments supported the safety of hydrogen peroxide bleaching strips both on surface and subsurface enamel, DEJ, and dentin ultrastructure. Raman spectroscopy analysis demonstrated no obvious effects of bleaching treatments on the microchemical composition of enamel and dentin. These results confirm that tooth bleaching with hydrogen peroxide whitening strips does not produce changes in surface

An ultrastructural study of cell-cell interactions in capture organs of the nematophagous fungus Arthrobotrys oligospora

NARCIS (Netherlands)

Veenhuis, Marten; Nordbring-Hertz, Birgit; Harder, Willem

1985-01-01

A detailed ultrastructural analysis was made of interactions between individual cells within the same adhesive network (trap) of the nematophagous fungus Arthrobotrys oligospora. These interactions were confined to traps which had captured nematodes, and occurred concurrently with the

Structural and ultrastructural study of the rabbit kidney exposed to carbamate insecticide

Directory of Open Access Journals (Sweden)

Viera Almášiová

2014-01-01

Full Text Available The aim of the present study was to determine the influence of orally administered insecticide bendiocarb on the structure and ultrastructure of the kidney parenchyma in rabbits. Bendiocarb in the form of capsules (96% Bendiocarb, Bayer, at a dose of 5 mg/kg of body weight was fed daily for 3 days. After sampling, kidney sections of experimental and control animals were evaluated. Under a light and electron microscope the diffuse degenerative changes in kidney cortex and medulla were noted. Light microscopy revealed that the renal corpuscles had normal structure, but other nephron components and the collecting ducts were invariably changed. The epithelial cells inside the proximal and distal tubules and collecting ducts possessed increased quantity of cytoplasmic vacuoles and some tubular sections showed cellular sloughing and necrotization. The cells within the thin limbs of the Henley’s loops had normal histological structure except for sporadic necrotizing cells within some segments. The ultrastructural evaluation showed extensive cytoplasmic vacuolisation and degenerative changes, such as mitochondrial swelling and shortening of basal infoldings within proximal and distal tubules, and microvilli reduction within proximal tubules. Cells of the collecting tubules exhibited a higher number of vacuoles and some cells had apparently reduced organelles. The cells of the thin limbs of the Henle’s loop showed more vacuolised cytoplasm, some tubular sections revealed cellular detachment between the adjacent epithelial cells and rare necrotising epithelial cells were observed. The described findings addressed in the present study indicate an adverse effect of bendiocarb on the kidney parenchyma in rabbits.

Ultrastructural and clinical evidence of subretinal debris accumulation in type 2 macular telangiectasia.

Science.gov (United States)

Cherepanoff, Svetlana; Killingsworth, Murray C; Zhu, Meidong; Nolan, Timothy; Hunyor, Alex P; Young, Stephanie H; Hageman, Gregory S; Gillies, Mark C

2012-11-01

To describe subretinal debris found on ultrastructural examination in an eye with macular telangiectasia (MacTel) type 2 and on optical coherence tomography (OCT) in a subset of patients with MacTel type 2. Blocks from the mid-periphery and temporal perifovea of an eye with clinically documented MacTel type 2 were examined with electron microscopy (EM). Cases came from the Sydney centre of the MacTel project and the practices of the authors. On EM examination, subretinal debris was found in the perifovea with accumulation of degenerate photoreceptor elements in the subretinal space. Despite the substantial subretinal debris, there was minimal retinal pigment epithelial (RPE) reaction. Focal defects were seen in the inner limiting membrane in the perifovea. Of the 65 Sydney MacTel project participants, three (5%) had prominent yellow material at the fovea. OCT revealed smooth mounds between the RPE and the ellipsoid region. The material was hyperautofluorescent. This study suggests that subretinal accumulation of photoreceptor debris may be a feature of MacTel type 2. Ultrastructural and OCT evidence of disease beyond the vasculature, involving photoreceptors and Muller cells, is presented.

An ultrastructural and irradiation study of diffuse and localised kinetochore

International Nuclear Information System (INIS)

Bokhari, F.S.

1979-05-01

An electron microscope study of plant types Luzula nivea and Cyperus eragrostis with diffuse kinetochores and Crepis neglecta with localised kinetochore showed that Luzula has a rather different kinetochore organisation from Cyperus, with features approaching the localised type of Crepis. These studies included an examination of the ultrastructure of the kinetochore at metaphase at low magnification in control and irradiated material of Luzula; the chromosomal ultrastructure at high magnification at interphase and all stages of mitosis in Luzula, Cyperus and Crepis; and the ultrastructure of the nucleolus in Luzula, Cyperus and Crepis. Light microscopic studies were also performed showing the effects of irradiation on first mitotic division in Cyperus, Luzula and Crepis, mitotic aberrations in Cyperus and Crepis and meiosis in Cyperus. Finally, the survival with the diffuse as opposed to the localised kinetochore in M 1 and M 2 generations following seed irradiation was studied. (U.K.)

Nucleolar ultrastructure in bovine nuclear transfer embryos

DEFF Research Database (Denmark)

Kanka, J; Smith, S D; Soloy, E

1999-01-01

in nuclear morphology as a transformation of the nucleolus precursor body into a functional rRNA synthesising nucleolus with a characteristic ultrastructure. We examined nucleolar ultrastructure in bovine in vitro produced (control) embryos and in nuclear transfer embryos reconstructed from a MII phase...... at 1 hr after fusion and, by 3 hr after fusion, it was restored again. At this time, the reticulated fibrillo-granular nucleolus had an almost round shape. The nucleolar precursor body seen in the two-cell stage nuclear transfer embryos consisted of intermingled filamentous components and secondary...... time intervals after fusion. In the two-cell stage nuclear transfer embryo, the originally reticulated nucleolus of the donor blastomere had changed into a typical nucleolar precursor body consisting of a homogeneous fibrillar structure. A primary vacuole appeared in the four-cell stage nuclear...

Intravitreal Injection of Ranibizumab and CTGF shRNA Improves Retinal Gene Expression and Microvessel Ultrastructure in a Rodent Model of Diabetes

Directory of Open Access Journals (Sweden)

Bojie Hu

2014-01-01

Full Text Available Therapeutic modalities targeting vascular endothelial growth factor (VEGF have been used to treat neovascularization and macular edema. However, anti-VEGF treatment alone may cause up-regulation of connective tissue growth factor (CTGF in the retina, increasing the risk of fibrosis and tractional retinal detachment. Therefore, in this study, we employ a novel dual-target intervention that involves intravitreal injection of the VEGF inhibitor ranibizumab and a transfection reagent-treated non-viral vector carrying anti-CTGF short hairpin RNA (shRNA driven by human RNA polymerase III promoter U6. The effects of the dual-target intervention on the expression of VEGF and CTGF and on microvessel ultrastructure were examined in retina of streptozocin-induced diabetic rats. CTGF was significantly up-regulated at week 8 after diabetic induction, whereas VEGF was not up-regulated until week 10. The high expression of both genes was maintained at week 12. Transmission electron microscopy also revealed progressive exacerbation of microvessel ultrastructure during the same period. In addition, ranibizumab significantly lowered VEGF but elevated CTGF mRNA, whereas CTGF shRNA significantly reduced the mRNA levels of both CTGF and VEGF in diabetic retinas. Importantly, dual-target intervention normalized the transcript levels of both target genes and ameliorated retinal microvessel ultrastructural damage better than either single-target intervention. These results suggest the advantages of dual-target over single-target interventions in diabetic retina and reveal a novel therapeutic modality for diabetic retinopathy.

Genome sequencing and analysis reveals possible determinants of Staphylococcus aureus nasal carriage

Directory of Open Access Journals (Sweden)

Cole Alexander M

2008-09-01

Full Text Available Abstract Background Nasal carriage of Staphylococcus aureus is a major risk factor in clinical and community settings due to the range of etiologies caused by the organism. We have identified unique immunological and ultrastructural properties associated with nasal carriage isolates denoting a role for bacterial factors in nasal carriage. However, despite extensive molecular level characterizations by several groups suggesting factors necessary for colonization on nasal epithelium, genetic determinants of nasal carriage are unknown. Herein, we have set a genomic foundation for unraveling the bacterial determinants of nasal carriage in S. aureus. Results MLST analysis revealed no lineage specific differences between carrier and non-carrier strains suggesting a role for mobile genetic elements. We completely sequenced a model carrier isolate (D30 and a model non-carrier strain (930918-3 to identify differential gene content. Comparison revealed the presence of 84 genes unique to the carrier strain and strongly suggests a role for Type VII secretion systems in nasal carriage. These genes, along with a putative pathogenicity island (SaPIBov present uniquely in the carrier strains are likely important in affecting carriage. Further, PCR-based genotyping of other clinical isolates for a specific subset of these 84 genes raise the possibility of nasal carriage being caused by multiple gene sets. Conclusion Our data suggest that carriage is likely a heterogeneic phenotypic trait and implies a role for nucleotide level polymorphism in carriage. Complete genome level analyses of multiple carriage strains of S. aureus will be important in clarifying molecular determinants of S. aureus nasal carriage.

Echinococcus multilocularis Leuckart, 1863 (Taeniidae): new data on sperm ultrastructure.

Science.gov (United States)

Miquel, Jordi; Świderski, Zdzisław; Azzouz-Maache, Samira; Pétavy, Anne-Françoise

2016-06-01

The present study establishes the ultrastructural organisation of the mature spermatozoon of Echinococcus multilocularis, which is essential for future research on the location of specific proteins involved in the sperm development in this species and also in Echinococcus granulosus. Thus, the ultrastructural characteristics of the sperm cell are described by means of transmission electron microscopy. The spermatozoon of E. multilocularis is a filiform cell, which is tapered at both extremities and lacks mitochondria. It exhibits all the characteristics of type VII spermatozoon of tapeworms, namely a single axoneme, crested bodies, spiralled cortical microtubules and nucleus, a periaxonemal sheath and intracytoplasmic walls. Other characteristics observed in the male gamete are the presence of a >900-nm long apical cone in its anterior extremity and only the axoneme in its posterior extremity. The ultrastructural characters of the spermatozoon of E. multilocularis are compared with those of other cestodes studied to date, with particular emphasis on representatives of the genus Taenia. The most interesting finding concerns the presence of two helical crested bodies in E. multilocularis while in the studied species of Taenia, there is only one crested body. Future ultrastructural studies of other species of the genus Echinococcus would be of particular interest in order to confirm whether or not the presence of two crested bodies is a characteristic of this genus.

Nanoscale Correlated Disorder in Out-of-Equilibrium Myelin Ultrastructure.

Science.gov (United States)

Campi, Gaetano; Di Gioacchino, Michael; Poccia, Nicola; Ricci, Alessandro; Burghammer, Manfred; Ciasca, Gabriele; Bianconi, Antonio

2018-01-23

Ultrastructural fluctuations at nanoscale are fundamental to assess properties and functionalities of advanced out-of-equilibrium materials. We have taken myelin as a model of supramolecular assembly in out-of-equilibrium living matter. Myelin sheath is a simple stable multilamellar structure of high relevance and impact in biomedicine. Although it is known that myelin has a quasi-crystalline ultrastructure, there is no information on its fluctuations at nanoscale in different states due to limitations of the available standard techniques. To overcome these limitations, we have used scanning micro X-ray diffraction, which is a unique non-invasive probe of both reciprocal and real space to visualize statistical fluctuations of myelin order of the sciatic nerve of Xenopus laevis. The results show that the ultrastructure period of the myelin is stabilized by large anticorrelated fluctuations at nanoscale, between hydrophobic and hydrophilic layers. The ratio between the total thickness of hydrophilic and hydrophobic layers defines the conformational parameter, which describes the different states of myelin. Our key result is that myelin in its out-of-equilibrium functional state fluctuates point-to-point between different conformations showing a correlated disorder described by a Levy distribution. As the system approaches the thermodynamic equilibrium in an aged state, the disorder loses its correlation degree and the structural fluctuation distribution changes to Gaussian. In a denatured state at low pH, it changes to a completely disordered stage. Our results aim to clarify the degradation mechanism in biological systems by associating these states with ultrastructural dynamic fluctuations at nanoscale.

Ultrastructural and metabolic changes in osteoblasts exposed to uranyl nitrate

International Nuclear Information System (INIS)

Tasat, D.R.; Orona, N.S.; Mandalunis, P.M.; Cabrini, R.L.; Ubios, A.M.

2007-01-01

Exposure to uranium is an occupational hazard to workers who continually handle uranium and an environmental risk to the population at large. Since the cellular and molecular pathways of uranium toxicity in osteoblast cells are still unknown, the aim of the present work was to evaluate the adverse effects of uranyl nitrate (UN) on osteoblasts both in vivo and in vitro. Herein we studied the osteoblastic ultrastructural changes induced by UN in vivo and analyzed cell proliferation, generation of reactive oxygen species (ROS), apoptosis, and alkaline phosphatase (APh) activity in osteoblasts exposed to various UN concentrations (0.1, 1, 10, and 100 μM) in vitro. Cell proliferation was quantified by means of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, ROS was determined using the nitro blue tetrazolium test, apoptosis was morphologically determined using Hoechst 3332 and APh activity was assayed spectrophotometrically. Electron microscopy revealed that the ultrastructure of active and inactive osteoblasts exposed to uranium presented cytoplasmic and nuclear alterations. In vitro, 1-100 μM UN failed to modify cell proliferation ratio and to induce apoptosis. ROS generation increased in a dose-dependent manner in all tested doses. APh activity was found to decrease in 1-100 μM UN-treated cells vs. controls. Our results show that UN modifies osteoblast cell metabolism by increasing ROS generation and reducing APh activity, suggesting that ROS may play a more complex role in cell physiology than simply causing oxidative damage. (orig.)

A proteomic and ultrastructural characterization of Aspergillus fumigatus' conidia adaptation at different culture ages.

Science.gov (United States)

Anjo, Sandra I; Figueiredo, Francisco; Fernandes, Rui; Manadas, Bruno; Oliveira, Manuela

2017-05-24

The airborne fungus Aspergillus fumigatus is one of the most common agents of human fungal infections with a remarkable impact on public health. However, A. fumigatus conidia atmospheric resistance and longevity mechanisms are still unknown. Therefore, in this work, the processes underlying conidial adaptation were studied by a time course evaluation of the proteomics and ultrastructural changes of A. fumigatus' conidia at three time-points selected according to relevant changes previously established in conidial survival rates. The proteomics characterization revealed that conidia change from a highly active metabolic to a dormant state, culminating in cell autolysis as revealed by the increased levels of hydrolytic enzymes. Structural characterization corroborates the proteomics data, with noticeable changes observed in mitochondria, nucleus and plasma membrane ultrastructure, accompanied by the formation of autophagic vacuoles. These changes are consistent with both apoptotic and autophagic processes, and indicate that the changes in protein levels may anticipate those in cell morphology. The findings presented in this work not only clarify the processes underlying conidial adaptation to nutrient limiting conditions but can also be exploited for improving infection control strategies and in the development of new therapeutical drugs. Additionally, the present study was deposited in a public database and thus, it may also be a valuable dataset to be used by the scientific community as a tool to understand and identified other potential targets associated with conidia resistance. Copyright © 2017. Published by Elsevier B.V.

Noise alters guinea pig's blood-labyrinth barrier ultrastructure and permeability along with a decrease of cochlear Claudin-5 and Occludin.

Science.gov (United States)

Wu, Yong-Xiang; Zhu, Guo-Xia; Liu, Xin-Qin; Sun, Fei; Zhou, Ke; Wang, Shuang; Wang, Chun-Mei; Jia, Jin-Wen; Song, Jian-Tao; Lu, Lian-Jun

2014-12-24

Noise exposure (NE) is a severe modern health hazard that induces hearing impairment. However, the noise-induced ultrastructural changes of blood-labyrinth barrier (BLB) and the potential involvements of tight junction proteins (TJP) remain inconclusive. We investigated the effects of NE on not only the ultrastructure of cochlea and permeability of BLB but also the expression of TJP within the guinea pig cochlea. Male albino guinea pigs were exposed to white noise for 4 h or 2 consecutive days (115 dB sound pressure level, 6 hours per day) and the hearing impairments and light microscopic change of BLB were evaluated with auditory brainstem responses (ABR) and the cochlear sensory epithelia surface preparation, respectively. The cochlear ultrastructure and BLB permeability after NE 2d were revealed with transmission electron microscope (TEM) and lanthanum nitrate-tracing techniques, respectively. The potential alterations of TJPs Claudin-5 and Occludin were quantified with immunohistochemistry and western blot. NE induced significant hearing impairment and NE 2d contributed to significant outer hair cell (OHC) loss that is most severe in the first row of outer hair cells. Furthermore, the loosen TJ and an obvious leakage of lanthanum nitrate particles beneath the basal lamina were revealed with TEM. Moreover, a dose-dependent decrease of Claudin-5 and Occludin was observed in the cochlea after NE. All these findings suggest that both decrease of Claudin-5 and Occludin and increased BLB permeability are involved in the pathologic process of noise-induced hearing impairment; however, the causal relationship and underlying mechanisms should be further investigated.

A comparison of neuronal growth cone and cell body membrane: electrophysiological and ultrastructural properties.

Science.gov (United States)

Guthrie, P B; Lee, R E; Kater, S B

1989-10-01

This study investigated a broad set of general electrophysiological and ultrastructural features of growth cone and cell body membrane of individual neurons where membrane from different regions of the same neuron can be directly compared. Growth cones were surgically isolated from identified adult Helisoma neurons in culture and compared with the cell body using whole-cell patch-clamp recording techniques. All isolated growth cones generated overshooting regenerative action potentials. Five neurons (buccal neurons B4, B5, and B19; pedal neurons P1 and P5) were selected that displayed distinctive action potential waveforms. In all cases, the growth cone action potential was indistinguishable from the cell body action potential and different from growth cones from other identified neurons. Two of these neurons (B5 and B19) were studied further using voltage-clamp procedures; growth cones and cell bodies again revealed major similarities within one neuron type and differences between neuron types. The only suggested difference between the growth cone and cell body was an apparent reduction in the magnitude of the A-current in the growth cone. Peak inward and outward current densities, as with other electrophysiological features, were different between neuron types, but were, again, similar between the growth cone and the cell body of the same neuron. Freeze-fracture analysis of intramembraneous particles (IMPs) was also performed on identified regions of the same neuron in culture. Both the density and the size distribution of IMPs were the same in growth cone, cell body, and neurite membranes. In these general electrophysiological and ultrastructural characteristics, therefore, growth cone membranes appear to retain the identity of the parent neuron cell body membrane.

Survival and ultrastructural features of peach palm (Bactris gasipaes, Kunth) somatic embryos submitted to cryopreservation through vitrification.

Science.gov (United States)

Heringer, Angelo Schuabb; Steinmacher, Douglas André; Schmidt, Éder Carlos; Bouzon, Zenilda Laurita; Guerra, Miguel Pedro

2013-10-01

Bactris gasipaes (Arecaceae), also known as peach palm, was domesticated by Amazonian Indians and is cultivated for its fruit and heart-of-palm, a vegetable grown in the tree's inner core. Currently, the conservation of this species relies on in situ conditions and field gene banks. Complementary conservation strategies, such as those based on in vitro techniques, are indicated in such cases. To establish an appropriate cryopreservation protocol, this study aimed to evaluate the ultrastructural features of B. gasipaes embryogenic cultures submitted to vitrification and subsequent cryogenic temperatures. Accordingly, somatic embryo clusters were submitted to Plant Vitrification Solution 3 (PVS3). In general, cells submitted to PVS3 had viable cell characteristics associated with apparently many mitochondria, prominent nucleus, and preserved cell walls. Cells not incubated in PVS3 did not survive after the cryogenic process in liquid nitrogen. The best incubation time for the vitrification technique was 240 min, resulting in a survival rate of 37 %. In these cases, several features were indicative of quite active cell metabolism, including intact nuclei and preserved cell walls, an apparently many of mitochondria and lipid bodies, and the presence of many starch granules and condensed chromatin. Moreover, ultrastructure analysis revealed that overall cellular structures had been preserved after cryogenic treatment, thus validating the use of vitrification in conjunction with cryopreservation of peach palm elite genotypes, as well as wild genotypes, which carry a rich pool of genes that must be conserved.

Gamma radiation induced alterations in the ultrastructure of pancreatic islet, metabolism and enzymes in wistar rat

Energy Technology Data Exchange (ETDEWEB)

Daoo, J.V.; Suryawanshi, S.A. [Inst. of Science, Bombay (India)

1992-07-01

Effects of gamma irradiation (600 rads) on the ultrastructure of pancreatic islet, metabolism and some enzymes in wistar rat, are reported. Electron microscopic observations of endocrine pancreas revealed prominent changes in beta cells while alpha and delta cells were not much affected. Irradiation also inflicted hyperglycemia, increase in liver and muscle glycogen and decrease in insulin level. It has also increased the activity of enzymes but failed to produce significant changes in protein, lipid and mineral metabolism. (auth0008.

Ultrastructure of pea and cress root statocytes exposed to high gradient magnetic field

Science.gov (United States)

Belyavskaya, N. A.; Chernishov, V. I.; Polishchuk, O. V.; Kondrachuk, A. V.

As it was demonstrated by Kuznetsov & Hasenstein (1996) the high gradient magnetic field (HGMF) can produce a ponderomotive force that results in displacements of amyloplasts and causes the root response similar to the graviresponse. It was suggested that the HGMF could allow to imitate the effects of gravity in microgravity and/or change them in laboratory conditions correspondingly, as well as to study statolith-related processes in graviperception. Therefore, the correlation between the direction of the ponderomotive force resulting in statolith displacements and the direction of the HGMF-induced plant curvature can be the serious argument to support this suggestion and needs the detailed ultrastructural analysis. Seeds of dicotyledon Pisum sativum L. cv. Damir-2 and monocotyledon Lepidium sativum L. cv. P896 were soaked and grown in a vertical position on moist filter paper in chambers at room temperature. Tips of primary roots of vertical control, gravistimulated and exposed to HGMF seedlings were fixed for electron microscopy using conventional techniques. At ultrastructural level, we observed no significant changes in the volume of the individual statocytes or amyloplasts, relative volumes of cellular organelles (except vacuoles), number of amyloplasts per statocyte or surface area of endoplasmic reticulum. No consistent contacts between amyloplasts and any cellular structures, including plasma membrane, were revealed at any stage of magneto- and gravistimulation. By 5 min after onset of magnetostimulation, amyloplasts were located along cell wall distant from magnets. In HGMF, the locations of amyloplasts in columella cells were similar to those in horizontally-oriented roots up to 1 h stimulation. In the latter case, there were sometimes cytoplasmic spherical bodies with a dense vesicle-rich cytoplasm in pea statocytes, which were absent in seedlings exposed to HGMF. In cress root statocytes, both gravi- and magnetostimulation were found to cause the

Ultrastructural alterations in adult Schistosoma mansoni caused by artemether

Directory of Open Access Journals (Sweden)

Shuhua Xiao

2002-07-01

Full Text Available Progress has been made over the last decade with the development and clinical use of artemether as an agent against major human schistosome parasites. The tegument has been identified as a key target of artemether, implying detailed studies on ultrastructural damage induced by this compound. We performed a temporal examination, employing a transmission electron microscope to assess the pattern and extent of ultrastructural alterations in adult Schistosoma mansoni harboured in mice treated with a single dose of 400 mg/kg artemether. Eight hours post-treatment, damage to the tegument and subtegumental structures was seen. Tegumental alterations reached a peak 3 days after treatment and were characterized by swelling, fusion of distal cytoplasma, focal lysis of the tegumental matrix and vacuolisation. Tubercles and sensory organelles frequently degenerated or collapsed. Typical features of subtegumental alterations, including muscle fibres, syncytium and parenchyma tissues, were focal or extensive lysis, vacuolisation and degeneration of mitochondria. Severe alterations were also observed in gut epithelial cells and vitelline cells of female worms. Our findings of artemether-induced ultrastructural alterations in adult S. mansoni confirm previous results obtained with juvenile S. mansoni and S. japonicum of different ages.

Building blocks of the GIPU, Italian Group of Ultrastructural Pathology.

Science.gov (United States)

Papa, V; Costa, R; Cenacchi, G

2016-06-01

The Italian Group of Ultrastructural Pathology, GIPU, is a scientific organization committed to promote the art and science of Electron Microscopy (EM) in the pathology field in Italy, sharing its professional work with a public audience. The history of the GIPU goes back to 1990s when a founder group set up the Italian Group of Ultrastructural Diagnostic (GIDU) in Milan. The central focus of annual meetings was on EM, transmission and scanning one, about interesting cases in which it was instrumental in diagnosis. In the 1990s, ultrastructure was still the gold standard for cell/tissue morphology, biology, biochemistry, diagnostic pathology, and played an important role in tailored medicine. So, especially transmission EM, could play a critical role in the diagnosis of various diseases as in human as in animals. Best topics of the annual scientific meetings of the group were kidney, muscle, heart, and liver pathology, infertility, neuropathology, respiratory diseases, skin diseases, storage diseases, tumor pathology, infectious diseases, parasitology, veterinary pathology and more. Nowadays, EM is a method whose importance for diagnosis and pathology is well established: it is still essential in several pathologies, helpful in others, and welcome implemented in eclectic research pathology. Omission of EM likely makes the studies suboptimal and wasteful. So, from 2007 the name of the group has been changed to the Italian Group of Ultrastructural Pathology (GIPU) to favor broader applications of EM also to pathology research field. During last decades, GIDU/GIPU has interconnected with international (Society for Ultrastructural Pathology) and european (European Society of Pathology and Joint Meeting with the European Electron Microscopy Working Group) scientific society, according its statute. By 1991, GIPU has had 40 members: membership in this Group is still open and welcome to all pathologists, PhD, electron microscopy technologists, pathology trainees, and

Hematology, cytochemistry and ultrastructure of blood cells in fishing cat (Felis viverrina)

OpenAIRE

Prihirunkit, Kreangsak; Salakij, Chaleow; Apibal, Suntaree; Narkkong, Nual-Anong

2007-01-01

Hematological, cytochemical and ultrastructural features of blood cells in fishing cat (Felis viverrina) were evaluated using complete blood cell counts with routine and cytochemical blood stains, and scanning and transmission electron microscopy. No statistically significant difference was found in different genders of this animal. Unique features of blood cells in this animal were identified in hematological, cytochemical and ultrastructural studies. This study contributes to broaden hemato...

Ultrastructural and Molecular Characterisation of an Heterosporis-Like Microsporidian in Australian Sea Snakes (Hydrophiinae.

Directory of Open Access Journals (Sweden)

Amber K Gillett

Full Text Available Four sea snakes (two Hydrophis major, one Hydrophis platurus, one Hydrophis elegans were found washed ashore on different beaches in the Sunshine Coast region and Fraser Island in Queensland, Australia between 2007-2013. Each snake had multiple granulomas and locally extensive regions of pallor evident in the hypaxial and intercostal musculature along the body. Lesions in two individuals were also associated with vertebral and rib fractures. Histological examination revealed granulomas scattered throughout skeletal muscle, subcutaneous adipose tissue and fractured bone. These were composed of dense aggregates of microsporidian spores surrounded by a mantle of macrophages. Sequences (ssrRNA were obtained from lesions in three sea snakes and all revealed 99% similarity with Heterosporis anguillarum from the Japanese eel (Anguillarum japonica. However, ultrastructural characteristics of the organism were not consistent with those of previous descriptions. Electron microscopic examination of skeletal muscle revealed large cysts (not xenomas bound by walls of fibrillar material (Heterosporis-like sporophorocyst walls were not detected. The cysts contained numerous mature microsporidian spores arranged in small clusters, sometimes apparently within sporophorous vesicles. The microspores were monomorphic, oval and measured 2.5-3.0 μm by 1.6-1.8 μm. They contained isofilar polar filaments with 11 (infrequently 9-12 coils arranged in two ranks. This is the first published report of a microsporidian infection in hydrophiid sea snakes. This discovery shows microsporidia with molecular affinities to Heterosporis anguillarum but ultrastructural characters most consistent with the genus Pleistophora (but no hitherto described species. Further studies are required to determine whether the microsporidian presented here belongs to the genus Heterosporis, or to a polymorphic species group as suggested by the recognition of a robust Pleistophora

Role of lycopene against spleen oxidative stress induced by sodium fluoride and gamma rays:Ultrastructural Changes

International Nuclear Information System (INIS)

Abd El Azeem, M.G.

2011-01-01

In connection with earlier studies, response of spleen ultrastructure effects of sodium fluoride (NaF) was examined. Sodium fluoride is a serious public health problem in many parts of the world, as in the case of many chronic degenerative diseases, increased production of reactive oxygen species has been considered to play an important role, even in the pathogenesis of chronic fluoride toxicity. Ionizing radiation (IR) is known to induce oxidative stress through generation of reactive oxygen species (ROS) resulting in imbalance of the pro-oxidant and antioxidant in the cells, which is suggested to culminate in cell death. The present study have been designed to evaluate the possible protective role of lycopene on spleen injure from the sodium fluoride (NaF) and gamma radiation in male mice. Ultrastructural studies were utilized for evaluation of these oxidative stress. Results showed that mice received (NaF) dose, lymphocyte revealed most appear with crystallized acicular structures and large specific 2 Gy granules they have dense internal crystalloid structure of variable shapes and densities. Interstitial haemorrhage, inflammatory area and, pyknotic nuclei with dense nuclear chromatin were observed .Their cytoplasm contained dilated endoplasmic reticulum, and active lysosomes as a result of the stress action of NaF. Whole body exposure of male mice to 2 Gy gamma radiation showing lymphocytes have pyknotic nuclei with dense nuclear chromatin, swollen mitochondria and active lysosomes, and fragmented of endoplasmic reticulum were also seen. The bundles of collagen fibrils among of the peri lymphocyte space accompanied with vacuolated cytoplasm area. Treatment of mice with lycopene (5 mg/kg, oral gavage) for 7 days, before NaF or IR, ameliorated the ultrastructural injury of the spleen induced by NaF and/or IR. Therefore, the present results revealed that lycopene has a protective effect against NaF and/or IR-induced spleen toxicity by antagonizing the free

Chemical-Free Technique to Study the Ultrastructure of Primary Cilium.

Science.gov (United States)

Mohieldin, Ashraf M; AbouAlaiwi, Wissam A; Gao, Min; Nauli, Surya M

2015-11-02

A primary cilium is a hair-like structure with a width of approximately 200 nm. Over the past few decades, the main challenge in the study of the ultrastructure of cilia has been the high sensitivity of cilia to chemical fixation, which is required for many imaging techniques. In this report, we demonstrate a combined high-pressure freezing (HPF) and freeze-fracture transmission electron microscopy (FFTEM) technique to examine the ultrastructure of a cilium. Our objective is to develop an optimal high-resolution imaging approach that preserves cilia structures in their best natural form without alteration of cilia morphology by chemical fixation interference. Our results showed that a cilium has a swelling-like structure (termed bulb), which was previously considered a fixation artifact. The intramembrane particles observed via HPF/FFTEM indicated the presence of integral membrane proteins and soluble matrix proteins along the ciliary bulb, which is part of an integral structure within the ciliary membrane. We propose that HPF/FFTEM is an important and more suitable chemical-free method to study the ultrastructure of primary cilia.

Effects of salicylate on the inflammatory genes expression and synaptic ultrastructure in the cochlear nucleus of rats.

Science.gov (United States)

Hu, Shou-Sen; Mei, Ling; Chen, Jian-Yong; Huang, Zhi-Wu; Wu, Hao

2014-04-01

Aspirin (salicylate), as a common drug that is frequently used for long-term treatment in a clinical setting, has the potential to cause reversible tinnitus. However, few reports have examined the inflammatory cytokines expression and alteration of synaptic ultrastructure in the cochlear nucleus (CN) in a rat model of tinnitus. The tinnitus-like behavior of rats were detected by the gap prepulse inhibition of acoustic startle (GPIAS) paradigm. We investigated the expression levels of the tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), N-methyl D-aspartate receptor subunit 2A (NR2A) mRNA and protein in the CN and compared synapses ultrastructure in the CN of tinnitus rats with normal ones. GPIAS showed that rats with long-term administration of salicylate were experiencing tinnitus, and the mRNA and protein expression levels of TNF-α and NR2A were up-regulated in chronic treatment groups, and they returned to baseline 14 days after cessation of treatment. Furthermore, compared to normal rats, repetitive salicylate-treated rats showed a greater number of presynaptic vesicles, thicker and longer postsynaptic densities, increased synaptic interface curvature. These data revealed that chronic salicylate administration markedly, but reversibly, induces tinnitus possibly via augmentation of the expression of TNF-α and NR2A and cause changes in synaptic ultrastructure in the CN. Long-term administration of salicylate causes neural plasticity changes at the CN level.

[An ultrastructural study of oogenesis in the planarian Schmidtea mediterranea (Platyhelminthe, Paludicola)].

Science.gov (United States)

Harrath, Abdul Halim; Alwasal, Saleh H; Alhazza, Ibrahim; Zghal, Fathia; Tekaya, Saida

2011-07-01

The ovary of the freshwater planarian Schmidtea mediterranea has been studied for the first time using both light and electron microscopy methods. The ultrastructure of the ovary revealed two types of cells: accessory cells and germinal cells at various stages of differentiation, distributed along a maturation axis. Initially, oogonia underwent cytoplasm growth due to the development of organelles, such as endoplasmic reticulum, Golgi complex, and mitochondria, which are all involved in the production of cytoplasmic inclusions or yolk globules. It is shown that the chromatoid body and fibrogranular aggregates may participate in the synthesis of vitelline inclusions. When completely mature, the oocytes have become larger, due to the accumulation of nutritive inclusions, which are round in shape and have a paracrystalline structure. These inclusions are interpreted as being yolk globules and may represent a kind of nutritive material for the developing embryo. These ultrastructural features of the ovary agree with the available phylogenetic tree, based on morphological and karyological characters that considers Schmidtea group as a genus and not a subgenus. The presence of sperm between the oocytes suggests that fertilization may occur within the ovary, representing an uncommon condition within the Triclads, in which fertilization usually takes places outside of the ovaries. Copyright © 2011 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Toxicological and ultrastructural analysis of the impact of pesticides used in temperate fruit crops on two populations of Chrysoperla externa (Neuroptera, Chrysopidae

Directory of Open Access Journals (Sweden)

Alexandre Pinho de Moura

2011-09-01

Full Text Available This study aimed to evaluate the effects of (g a.i. L-1 abamectin (0.02, carbaryl (1.73, sulphur (4.8, fenitrothion (0.75, methidathion (0.4, and trichlorfon (1.5 on the survival of larvae and pupae, on the oviposition of adults and hatching of eggs from treated Chrysoperla externa third-instar larvae from two different populations (Bento Gonçalves and Vacaria, Rio Grande do Sul State, Brazil. Morphological changes caused by abamectin to eggs laid by C. externa from Vacaria population were evaluated by mean of ultrastructural analysis. The pesticides were applied on glass plates. Distilled water was used as control. For the evaluation of larvae mortality, a fully randomized experimental design in a 2 x 7 (two populations x seven treatments factorial scheme was used, whereas for the effects of the compounds on oviposition capacity and egg viability, a 2 x 4 factorial scheme was used. Carbaryl, fenitrothion, and methidathion caused 100% mortality of larvae. Abamectin reduced the hatching of eggs from treated third-instar larvae of both populations; however, this pesticide presented highest toxicity on insects from Vacaria. The ultrastructural analysis showed that abamectin caused malformations in micropyle and in chorion external surface of C. externa eggs. Based in the total effect (E, carbaryl, fenitrothion, and methidathion are harmful to C. externa; trichlorfon is harmless to third-instar larvae, while abamectin and sulphur are harmless and slightly harmful to third-instar larvae from Bento Gonçalves and Vacaria, respectively.

Ultrastructure and Development of Pasteuria sp. (S-1 strain), an Obligate Endoparasite of Belonolaimus longicaudatus (Nemata: Tylenchida).

Science.gov (United States)

Giblin-Davis, R M; Williams, D S; Wergin, W P; Dickson, D W; Hewlett, T E; Bekal, S; Becker, J O

2001-12-01

Pasteuria sp., strain S-1, is a gram-positive, obligate endoparasitic bacterium that uses the phytoparasitic sting nematode, Belonolaimus longicaudatus, as its host in Florida. The host attachment of S-1 appears to be specific to the genus Belonolaimus with development occurring only in juveniles and adults of B. longicaudatus. This bacterium is characterized from other described species of Pasteuria using ultrastructure of the mature endospore. Penetration, development, and sporogenesis were elucidated with TEM, LTSEM, and SEM and are similar to other nematode-specific Pasteuria. Recent analysis of 16S rDNA sequence homology confirms its congeneric ranking with other Pasteuria species and strains from nematodes and cladocerans, and corroborates ultrastructural, morphological, morphometric, and host-range evidence suggesting separate species status.

Sodium chloride stress induced morphological and ultrastructural changes in Aspergillus repens.

Science.gov (United States)

Kelavkar, U; Rao, K S; Ghhatpar, H S

1993-06-01

Halotolerant fungus, A. repens, showed a considerable difference in its growth rate, morphology, ultrastructural and molecular composition under NaCl stress as compared to control i.e. non-stressed condition. Light microscopic observations revealed significant differences in their mycelial thickness, their branching and septa. Transmission electron microscopic observations of both the conditions depicted significant differences in the qualitative and quantitative changes in mitochondria. Frequent pinocytotic vesiculation (vacuoles) of plasma membrane was observed in fungus under stress but no such vesiculation in control. The multivesiculate structures observed under stress with their origin from the cell membranes and subsequent release into vacuoles have not been reported in fungi under normal physiological conditions. The observations on pinocytosis are discussed in relation to ion compartmentation and salt tolerance in A. repens.

Ultrastructure of the surface of dental enamel with molar incisor hypomineralization (MIH) with and without acid etching.

Science.gov (United States)

Bozal, Carola B; Kaplan, Andrea; Ortolani, Andrea; Cortese, Silvina G; Biondi, Ana M

2015-01-01

The aim of the present work was to analyze the ultrastructure and mineral composition of the surface of the enamel on a molar with MIH, with and without acid etching. A permanent tooth without clinical MIH lesions (control) and a tooth with clinical diagnosis of mild and moderate MIH, with indication for extraction, were processed with and without acid etching (H3PO4 37%, 20") for observation with scanning electron microscope (SEM) ZEISS (Supra 40) and mineral composition analysis with an EDS detector (Oxford Instruments). The control enamel showed normal prismatic surface and etching pattern. The clinically healthy enamel on the tooth with MIH revealed partial loss of prismatic pattern. The mild lesion was porous with occasional cracks. The moderate lesion was more porous, with larger cracks and many scales. The mineral composition of the affected surfaces had lower Ca and P content and higher O and C. On the tooth with MIH, even on normal looking enamel, the demineralization does not correspond to an etching pattern, and exhibits exposure of crystals with rods with rounded ends and less demineralization in the inter-prismatic spaces. Acid etching increased the presence of cracks and deep pores in the adamantine structure of the enamel with lesion. In moderate lesions, the mineral composition had higher content of Ca, P and Cl. Enamel with MIH, even on clinically intact adamantine surfaces, shows severe alterations in the ultrastructure and changes in ionic composition, which affect the acid etching pattern and may interfere with adhesion.

Comparative transcriptome analysis reveals carbohydrate and lipid metabolism blocks in Brassica napus L. male sterility induced by the chemical hybridization agent monosulfuron ester sodium.

Science.gov (United States)

Li, Zhanjie; Cheng, Yufeng; Cui, Jianmin; Zhang, Peipei; Zhao, Huixian; Hu, Shengwu

2015-03-17

Chemical hybridization agents (CHAs) are often used to induce male sterility for the production of hybrid seeds. We previously discovered that monosulfuron ester sodium (MES), an acetolactate synthase (ALS) inhibitor of the herbicide sulfonylurea family, can induce rapeseed (Brassica napus L.) male sterility at approximately 1% concentration required for its herbicidal activity. To find some clues to the mechanism of MES inducing male sterility, the ultrastructural cytology observations, comparative transcriptome analysis, and physiological analysis on carbohydrate content were carried out in leaves and anthers at different developmental stages between the MES-treated and mock-treated rapeseed plants. Cytological analysis revealed that the plastid ultrastructure was abnormal in pollen mother cells and tapetal cells in male sterility anthers induced by MES treatment, with less material accumulation in it. However, starch granules were observed in chloroplastids of the epidermis cells in male sterility anthers. Comparative transcriptome analysis identified 1501 differentially expressed transcripts (DETs) in leaves and anthers at different developmental stages, most of these DETs being localized in plastid and mitochondrion. Transcripts involved in metabolism, especially in carbohydrate and lipid metabolism, and cellular transport were differentially expressed. Pathway visualization showed that the tightly regulated gene network for metabolism was reprogrammed to respond to MES treatment. The results of cytological observation and transcriptome analysis in the MES-treated rapeseed plants were mirrored by carbohydrate content analysis. MES treatment led to decrease in soluble sugars content in leaves and early stage buds, but increase in soluble sugars content and decrease in starch content in middle stage buds. Our integrative results suggested that carbohydrate and lipid metabolism were influenced by CHA-MES treatment during rapeseed anther development, which might

Phenotypic plasticity of wall ultrastructure in the green alga Pediastrum s.l. (Chlorophyta, Sphaeropleales

Directory of Open Access Journals (Sweden)

Lenarczyk Joanna

2016-07-01

Full Text Available This study examined wall ultrastructure variability in the microscopic green alga Pediastrum s.l. Its value as a diagnostic character is discussed. Field and cultured material of 21 taxa were compared using light and scanning electron microscopy. Nine ultrastructural elements occurring on the surface of Pediastrum are documented with LM and SEM micrographs. The highest number of taxa showed reticulate ornamentation composed of a trigonal mesh and granules situated on its corners. The paper considers the use of wall ultrastructure to reconcile traditional and modern taxonomical systems with regard to Pediastrum varieties, and addresses the phylogenetic relationships between strains representing different varieties.

Effect of exogenous prolactin on ultrastructure of pinealocyte in female pigs during puberty

International Nuclear Information System (INIS)

Przybylska, B.; Dusza, L.; Lewczuk, B.; Ciesielska-Myszka, L.

1994-01-01

Influence of the administration of prolactin to female swine during puberty on the ultrastructure of pinealocytes has been examined by means of morphometric analysis. Prolactin administration for 15 consecutive days resulted in a decrease in the cytoplasmic dense bodies type MBB-2, lysosomes and multivesicular bodies. Some differences in structure of pinealocytes were also observed. Prolactin appeared to stimulate the process of transformation of cytoplasmic dense bodies. (author). 28 refs, 5 figs

Effect of exogenous prolactin on ultrastructure of pinealocyte in female pigs during puberty

Energy Technology Data Exchange (ETDEWEB)

Przybylska, B.; Dusza, L.; Lewczuk, B.; Ciesielska-Myszka, L. [Akademia Rolniczo-Technicza, Olsztyn (Poland)

1994-12-31

Influence of the administration of prolactin to female swine during puberty on the ultrastructure of pinealocytes has been examined by means of morphometric analysis. Prolactin administration for 15 consecutive days resulted in a decrease in the cytoplasmic dense bodies type MBB-2, lysosomes and multivesicular bodies. Some differences in structure of pinealocytes were also observed. Prolactin appeared to stimulate the process of transformation of cytoplasmic dense bodies. (author). 28 refs, 5 figs.

Ultrastructure observation on the cells at different life history stages of Cryptocaryon irritans (Ciliophora: Prostomatea), a parasitic ciliate of marine fishes.

Science.gov (United States)

Ma, Rui; Ni, Bing; Fan, Xinpeng; Warren, Alan; Yin, Fei; Gu, Fukang

2016-09-01

Cells of Cryptocaryon irritans at different life history stages were studied using both light and electron microscopy. The characteristics of several organelles were revealed for the first time at the ultrastructural level. It was confirmed that the cytostome of trophonts, protomonts and theronts was surrounded by cilium-palp triplets rather than ciliary triplets. The nematodesmata underlying the circumoral dikinetids were single bundles, whereas these were always paired in Prorodontids. Toxicysts were present in late-stage tomonts and theronts, but were absent in trophonts and protomonts. We posited that toxicysts might play a role in infection and invasion of host-fish tissue by theronts. The adoral brosse was unlike that of any other family of the class Prostomatea based on its location and morphology. Membranous folds were present in trophonts, protomonts and theronts. These folds were longer and more highly developed in C. irritans than in exclusively free-living prostome ciliates suggesting that they might be linked to parasitism in C. irritans. Trophonts, protomonts and theronts had multiple contractile vacuoles. The basic ultrastructure of the contractile vacuole of C. irritans was similar to that of other kinetofragminophoran ciliates. They might play different roles in different stages of the life cycle since their ultrastructure varied among trophonts, protomonts and theronts.

Ultrastructural Characterization of the Glomerulopathy in Alport Mice by Helium Ion Scanning Microscopy (HIM).

Science.gov (United States)

Tsuji, Kenji; Suleiman, Hani; Miner, Jeffrey H; Daley, James M; Capen, Diane E; Păunescu, Teodor G; Lu, Hua A Jenny

2017-09-15

The glomerulus exercises its filtration barrier function by establishing a complex filtration apparatus consisting of podocyte foot processes, glomerular basement membrane and endothelial cells. Disruption of any component of the glomerular filtration barrier leads to glomerular dysfunction, frequently manifested as proteinuria. Ultrastructural studies of the glomerulus by transmission electron microscopy (TEM) and conventional scanning electron microscopy (SEM) have been routinely used to identify and classify various glomerular diseases. Here we report the application of newly developed helium ion scanning microscopy (HIM) to examine the glomerulopathy in a Col4a3 mutant/Alport syndrome mouse model. Our study revealed unprecedented details of glomerular abnormalities in Col4a3 mutants including distorted podocyte cell bodies and disorganized primary processes. Strikingly, we observed abundant filamentous microprojections arising from podocyte cell bodies and processes, and presence of unique bridging processes that connect the primary processes and foot processes in Alport mice. Furthermore, we detected an altered glomerular endothelium with disrupted sub-endothelial integrity. More importantly, we were able to clearly visualize the complex, three-dimensional podocyte and endothelial interface by HIM. Our study demonstrates that HIM provides nanometer resolution to uncover and rediscover critical ultrastructural characteristics of the glomerulopathy in Col4a3 mutant mice.

Changes in ultrastructure and histochemistry of two red macroalgae strains of Kappaphycus alvarezii (Rhodophyta, Gigartinales), as a consequence of ultraviolet B radiation exposure.

Science.gov (United States)

Schmidt, Eder Carlos; Scariot, Lidiane Angela; Rover, Ticiane; Bouzon, Zenilda Laurita

2009-12-01

Ultraviolet radiation (UVR) affects macroalgae in many important ways, including reduced growth rate, reduction of primary productivity and changes in cell biology and ultrastructure. Among red macroalgae, Kappaphycus alvarezii is of economic interest by its production of kappa carrageenan. Only a few reports have examined the changes in macroalgae ultrastructure and cell biology resulting from UVB radiation exposure. Therefore, we examined two strains of K. alvarezii (green and red) exposed to UVB for 3 h per day during 28 days and then processed them for histochemical and electron microscopy analysis. Reaction with Toluidine Blue showed an increase in the thickness of the cell wall and Periodic Acid-Schiff stain showed a decrease in the number of starch grains. UVBR also caused changes in the ultrastructure of cortical and subcortical cells, which included increased thickness of the cell wall and number of free ribosomes and plastoglobuli, reduced intracellular spaces, changes in the cell contour, and destruction of chloroplast internal organization. Based on these lines of evidence, it was evident by the ultrastructural changes observed that UVBR negatively affects intertidal macroalgae and, by extension, their economic viability.

[Ultrastructure and Raman Spectral Characteristics of Two Kinds of Acute Myeloid Leukemia Cells].

Science.gov (United States)

Liang, Hao-Yue; Cheng, Xue-Lian; Dong, Shu-Xu; Zhao, Shi-Xuan; Wang, Ying; Ru, Yong-Xin

2018-02-01

To investigate the Raman spectral characteristics of leukemia cells from 4 patients with acute promyelocytic leukemia (M 3 ) and 3 patients with acute monoblastic leukemia (M 5 ), establish a novel Raman label-free method to distinguish 2 kinds of acute myeloid leukemia cells so as to provide basis for clinical research. Leukemia cells were collected from bone marrow of above-mentioned patients. Raman spectra were acquired by Horiba Xplora Raman spectrometer and Raman spectra of 30-50 cells from each patient were recorded. The diagnostic model was established according to principle component analysis (PCA), discriminant function analysis (DFA) and cluster analysis, and the spectra of leukemia cells from 7 patients were analyzed and classified. Characteristics of Raman spectra were analyzed combining with ultrastructure of leukemia cells. There were significant differences between Raman spectra of 2 kinds of leukemia cells. Compared with acute monoblastic leukemia cells, the spectra of acute promyelocytic leukemia cells showed stronger peaks in 622, 643, 757, 852, 1003, 1033, 1117, 1157, 1173, 1208, 1340, 1551, 1581 cm -1 . The diagnostic models established by PCA-DFA and cluster analysis could successfully classify these Raman spectra of different samples with a high accuracy of 100% (233/233). The model was evaluated by "Leave-one-out" cross-validation and reached a high accuracy of 97% (226/233). The level of macromolecules of M 3 cells is higher than that of M 5 . The diagnostic models established by PCA-DFA can classify these Raman spectra of different cells with a high accuracy. Raman spectra shows consistent result with ultrastructure by TEM.

Morphology, Ultrastructure and Life Cycle of Vitrella brassicaformis n. sp., n. gen., a Novel Chromerid from the Great Barrier Reef

KAUST Repository

Oborní k, Miroslav; Modrý , David; Lukeš, Martin; Černotí ková -Stří brná , Eva; Cihlá ř, Jaromí r; Tesařová , Martina; Kotabová , Eva; Vancová , Marie; Prá šil, Ondřej; Lukeš, Julius

2012-01-01

on its ultrastructure, allowing insight into its life cycle. The novel alga differs significantly from the related chromerid C. velia in life cycle, morphology as well as the plastid genome. Analysis of photosynthetic pigments on the other hand

Adjuvant potential of virgin coconut oil extract on antiretroviral therapy-induced testicular toxicity: An ultrastructural study.

Science.gov (United States)

Ogedengbe, O O; Jegede, A I; Onanuga, I O; Offor, U; Peter, A I; Akang, E N; Naidu, E C S; Azu, O O

2018-04-01

The effects of Virgin coconut oil as an adjuvant to highly active antiretroviral therapy (HAART) were investigated on the testicular ultrastructure and biochemical markers in rats. Twenty male Sprague-Dawley rats, weighing 153-169 g were divided into four groups and treated as follows: control A (distilled water), B (HAART), C (HAART+Virgin coconut oil 10 ml/kg) and D (Virgin coconut oil [VCO] 10 ml/kg). Testicular segments were evaluated using transmission electron microscopy. Serum was assayed for testosterone, luteinising hormone, follicle stimulating hormone and testicular tissue for malondialdehyde and glutathione. Ultrastructure of basement membrane (Bm), mitochondria and spermatocytes was normal in the control group. HAART-treated group showed significant increase (p group. Mitochondrial cristae appear collapsed, and Sertoli cells showed cytoplasmic vacuolations. HAART+VCO group showed improved ultrastructural details in Bm, and Sertoli cell and Leydig cells show abundant lipid droplets. Virgin coconut oil-treated group showed thinning of Bm with otherwise normal ultrastructural features of organelles. HAART-treated group showed significant increase (p Virgin coconut oil improved testicular morphology and reversed HAART-induced ultrastructural alterations. Further studies on putative mechanism are required. © 2017 Blackwell Verlag GmbH.

Ultrastructural analysis of oral exfoliated epithelial cells of tobacco smokers and betel nut chewers: A scanning electron microscopy study

Directory of Open Access Journals (Sweden)

Sameera Shamim Khan

2016-01-01

Conclusion: In normal oral mucosa, cell surface morphology depends on the state of keratinization of the tissue. Thus, it could prove helpful in detecting any carcinomatous change at its incipient stage and also give an insight into the ultra-structural details of cellular differentiations in epithelial tissues.

Effects of heavy water on ultrastructural and functional status of Hep 2 and CHO cells lysosomes

International Nuclear Information System (INIS)

Buzgariu, Wanda; Caloianu, Maria; Zarnescu, Otilia; Cimpean, Anisoara; Titescu, Gh.; Stefanescu, I.

2002-01-01

The heavy water effects on the ultrastructure and function of Hep 2 and CHO lysosomal cell compartment were investigated using electron microscopy and enzymatic studies. The cell viability, measured by neutral red uptake assay, and the total protein content determination, have shown a dose dependent decrease in cell growth for both studied cell types. The electron microscopy study has revealed a progressive increase in number and size of lysosomes and autophagosomes after 96 h exposure to different deuterium concentration media in a dose dependent manner. The enzymatic determination in the lysosomal pellet revealed an increased acid phosphatase activity in both cell types (15% and 33% for Hep 2 and 24% and 52% for CHO, respectively) exposed to media with high (65%, 90%) D 2 O content. (authors)

Hematology, cytochemistry and ultrastructure of blood cells in fishing cat (Felis viverrina).

Science.gov (United States)

Prihirunkit, Kreangsak; Salakij, Chaleow; Apibal, Suntaree; Narkkong, Nual Anong

2007-06-01

Hematological, cytochemical and ultrastructural features of blood cells in fishing cat (Felis viverrina) were evaluated using complete blood cell counts with routine and cytochemical blood stains, and scanning and transmission electron microscopy. No statistically significant difference was found in different genders of this animal. Unique features of blood cells in this animal were identified in hematological, cytochemical and ultrastructural studies. This study contributes to broaden hematological resources in wildlife animals and provides a guideline for identification of blood cells in the fishing cat.

Phylogenetic analysis of HSP70 and cyt b gene sequences for Chinese Leishmania isolates and ultrastructural characteristics of Chinese Leishmania sp.

Science.gov (United States)

Yuan, Dongmei; Qin, Hanxiao; Zhang, Jianguo; Liao, Lin; Chen, Qiwei; Chen, Dali; Chen, Jianping

2017-02-01

Leishmaniasis is a worldwide epidemic disease caused by the genus Leishmania, which is still endemic in the west and northwest areas of China. Some viewpoints of the traditional taxonomy of Chinese Leishmania have been challenged by recent phylogenetic researches based on different molecular markers. However, the taxonomic positions and phylogenetic relationships of Chinese Leishmania isolates remain controversial, which need for more data and further analysis. In this study, the heat shock protein 70 (HSP70) gene and cytochrome b (cyt b) gene were used for phylogenetic analysis of Chinese Leishmania isolates from patients, dogs, gerbils, and sand flies in different geographic origins. Besides, for the interesting Leishmania sp. in China, the ultrastructure of three Chinese Leishmania sp. strains (MHOM/CN/90/SC10H2, SD, GL) were observed by transmission electron microscopy. Bayesian trees from HSP70 and cyt b congruently indicated that the 14 Chinese Leishmania isolates belong to three Leishmania species including L. donovani complex, L. gerbilli, and L. (Sauroleishmania) sp. Their identity further confirmed that the undescribed Leishmania species causing visceral Leishmaniasis (VL) in China is closely related to L. tarentolae. The phylogenetic results from HSP70 also suggested the classification of subspecies within L. donovani complex: KXG-918, KXG-927, KXG-Liu, KXG-Xu, 9044, SC6, and KXG-65 belong to L. donovani; Cy, WenChuan, and 801 were proposed to be L. infantum. Through transmission electron microscopy, unexpectedly, the Golgi apparatus were not observed in SC10H2, SD, and GL, which was similar to previous reports of reptilian Leishmania. The statistical analysis of microtubule counts separated SC10H2, SD, and GL as one group from any other reference strain (L. donovani MHOM/IN/80/DD8; L. tropica MHOM/SU/74/K27; L. gerbilli MRHO/CN/60/GERBILLI). The ultrastructural characteristics of Leishmania sp. partly lend support to the phylogenetic inference that

The ultrastructure of bone and its relevance to mechanical properties

Science.gov (United States)

Schwarcz, Henry P.; Abueidda, Diab; Jasiuk, Iwona

2017-09-01

Bone is a biologically generated composite material comprised of two major structural components: crystals of apatite and collagen fibrils. Computational analysis of the mechanical properties of bone must make assumptions about the geometric and topological relationships between these components. Recent transmission electron microscope (TEM) studies of samples of bone prepared using ion milling methods have revealed important previously unrecognized features in the ultrastructure of bone. These studies show that most of the mineral in bone lies outside the fibrils and is organized into elongated plates 5 nanometers (nm) thick, 80 nm wide and hundreds of nm long. These so-called mineral lamellae (MLs) are mosaics of single 5 nm-thick, 20 - 50 nm wide crystals bonded at their edges. MLs occur either stacked around the 50 nm-diameter collagen fibrils, or in parallel stacks of 5 or more MLs situated between fibrils. About 20% of mineral is in gap zones within the fibrils. MLs are apparently glued together into mechanically coherent stacks which break across the stack rather than delaminating. ML stacks should behave as cohesive units during bone deformation. Finite element computations of mechanical properties of bone show that the model including such features generates greater stiffness and strength than are obtained using conventional models in which most of the mineral, in the form of isolated crystals, is situated inside collagen fibrils.

Digital three-dimensional reconstruction and ultrastructure of the mouse proximal tubule

DEFF Research Database (Denmark)

Zhai, X.Y.; Birn, H.; Jensen, K.B.

2003-01-01

. In the medullary rays, these are arranged in layers outside the clusters of more superficial tubules. In contrast to rat and human kidney, no major segmental variation in the ultrastructure of the proximal tubule was identified, and no parameters enabled definition of distinct segments in this strain of mice......, detailed analyses of normal mouse kidney structure and organization are lacking. This study describes the 3D organization and ultrastructural, segmental variation of the mouse kidney proximal tubule. A total of 160 proximal tubules in three C57/BL/6J mouse kidneys were analyzed on 800 serial sections from...

Ultrastructure of Sheep Primordial Follicles Cultured in the Presence of Indol Acetic Acid, EGF, and FSH

Directory of Open Access Journals (Sweden)

Evelyn Rabelo Andrade

2011-01-01

Full Text Available The aim of this study was to investigate the ultrastructural characteristics of primordial follicles after culturing of sheep ovarian cortical slices in the presence of indol acetic acid (IAA, Epidermal Growth Factor (EGF, and FSH. To evaluate ultrastructure of primordial follicles cultured in MEM (control or in MEM containing IAA, EGF, and FSH, fragments of cultured tissue were processes for transmission electron microscopy. Except in the control, primordial follicles cultured in supplemented media for 6 d were ultrastructurally normal. They had oocyte with intact nucleus and the cytoplasm contained heterogeneous-sized lipid droplets and numerous round or elongated mitochondria with intact parallel cristae were observed. Rough endoplasmic reticulum (RER was rarely found. The granulosa cells cytoplasm contained a great number of mitochondria and abundant RER. In conclusion, the presence of IAA, EGF, and FSH helped to maintain ultrastructural integrity of sheep primordial follicles cultured in vitro.

Evaluation of the effects of albendazole and metronidazole on the ultrastructure of Giardia duodenalis, Trichomonas vaginalis and Spironucleus muris using transmission electron microscopy.

Science.gov (United States)

Oxberry, M E; Thompson, R C; Reynoldson, J A

1994-08-01

The three closely related parasitic protozoa, Giardia duodenalis, Trichomonas vaginalis and Spironucleus muris, all have very different sensitivities to albendazole and metronidazole. Ultrastructural studies reveal that the cytoskeletal elements of the ventral disk in G. duodenalis are affected by albendazole, whereas the other two parasites, neither of which possess this structure, are not affected by albendazole to the same extent. This suggests that albendazole may be having its primary affect on G. duodenalis by binding to cytoskeletal proteins and ultimately causing death of the parasite. Death may be occurring as the parasite loses its ability to adhere to the intestinal villi and obtain nutrients. Metronidazole showed a different pattern of activity against the three parasites. The evidence obtained from these ultrastructural studies supports the current theory that metronidazole adversely affects protozoa by disrupting inner cell membranes.

Morphological aspects of the rat kidney preserved by cold storage. III. Ultrastructural aspects.

Science.gov (United States)

Neagu, S; Gabrielescu, E; Codorean, E; Chirculescu, A R

1983-01-01

The ultrastructural changes of the white Wistar rat kidney, preserved by cold storage into two preservation media (Sacks and Plasmagel) are reported. For each medium two groups of kidney were used; for one of them the medium was used without additives and for the other stabilizing additives were added. The results showed the favourable effects of additives on the maintenance of the cellular ultrastructure during preservation, and more important the damages incurred when Plasmagel was used.

Ultrastructural and stereological analysis of trypanosomatidis of the genus Endotrypanum

Directory of Open Access Journals (Sweden)

Maurílio J. Soares

1991-06-01

Full Text Available Culture forms of four strains of Endotrypanum (E. schaudinni and E. monterogeii were processed for transmission electron microscopy and analyzed at the ultrastructural level. Quantitative data about some cytoplasmic organelles were obeined by stereology. All culture forms were promastigotes. In their cytoplasm four different organelles could be found: lipid inclusions (0,2-0,4 µm in diameter, mebrane-bounded vacuoles (0.10-0,28 µm in diameter, glycosomes (0,2-0,3 µm in diameter, and the mitochondrion. The kenetoplast appears as a thin band, except for the strain IM201, which possesses a broader structure, and possibly is not a member of this genus. Clusters of virus-like particles were seen in the cytoplasm of the strain LV88. The data obtained show that all strains have the typical morphological feature of the trypanosomatids. Only strain IM201 could be differentiated from the others, due to its larger kenetoplast-DNA network and its large mitochondrial and glycosomal relative volume. The morphometrical data did not allow the differentiation between E. schaudinni (strains IM217 and M6226 and E. monterogeii (strain LV88.

Ultrastructural Comparison of Hepatozoon ixoxo and Hepatozoon theileri (Adeleorina: Hepatozoidae), Parasitising South African Anurans.

Science.gov (United States)

Conradie, Roxanne; Cook, Courtney A; du Preez, Louis H; Jordaan, Anine; Netherlands, Edward C

2017-03-01

To date, only two haemogregarine parasite species have been described from South African anurans: Hepatozoon ixoxo, infecting toads of the genus Sclerophrys (syn. Amietophrynus); and Hepatozoon theileri, parasitising the common river frog, Amietia quecketti. Both species have been characterised using limited morphology, and molecular data from PCR amplified fragments of the 18S rRNA gene. However, no ultrastructural work has been performed thus far. The aim of this study was to add descriptive information on the two species by studying their ultrastructural morphology. Mature gamont stages, common in the peripheral blood of infected frogs, were examined by transmission electron microscopy. Results indicate that H. ixoxo and H. theileri share typical apicomplexan characteristics, but differ markedly in their external cellular structure. Hepatozoon ixoxo is an encapsulated parasite presenting a prominent cap at the truncate pole, and shows no visible modifications to the host cell membrane. In comparison, H. theileri does not present a capsule or cap, and produces marked morphological changes to its host cell. Scanning electron microscopy was performed to further examine the cytopathological effects of H. theileri, and results revealed small, knob-like protrusions on the erythrocyte surface, as well as notable distortion of the overall shape of the host cell. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

Gross, histological and ultrastructural morphology of the aglomerular kidney in the lined seahorse Hippocampus erectus.

Science.gov (United States)

Fogelson, S B; Yanong, R P E; Kane, A; Teal, C N; Berzins, I K; Smith, S A; Brown, C; Camus, A

2015-09-01

Histologic evaluation of the renal system in the lined seahorse Hippocampus erectus reveals a cranial kidney with low to moderate cellularity, composed of a central dorsal aorta, endothelial lined capillary sinusoids, haematopoietic tissue, fine fibrovascular stroma, ganglia and no nephrons. In comparison, the caudal kidney is moderately to highly cellular with numerous highly convoluted epithelial lined tubules separated by interlacing haematopoietic tissue, no glomeruli, fine fibrovascular stroma, numerous capillary sinusoids, corpuscles of Stannius and clusters of endocrine cells adjacent to large calibre vessels. Ultrastructural evaluation of the renal tubules reveals minimal variability of the tubule epithelium throughout the length of the nephron and the majority of tubules are characterized by epithelial cells with few apical microvilli, elaborate basal membrane infolding, rare electron dense granules and abundant supporting collagenous matrix. © 2015 The Fisheries Society of the British Isles.

Ultrastructure and mitochondrial numbers in pre- and postpubertal pig oocytes

DEFF Research Database (Denmark)

Pedersen, Hanne Skovsgaard; Callesen, Henrik; Løvendahl, Peter

2016-01-01

Prepubertal pig oocytes are associated with lower developmental competence. The aim of this experiment was to conduct an exhaustive survey of oocyte ultrastructure and to use a design-unbiased stereological approach to quantify the numerical density and total number of mitochondria in oocytes...... with different diameters from pre- and postpubertal pigs. The ultrastructure of smaller prepubertal immature oocytes indicated active cells in close contact with cumulus cells. The postpubertal oocytes were more quiescent cell types. The small prepubertal oocytes had a lower total mitochondrial number......, but no differences were observed in mitochondrial densities between groups. Mature postpubertal oocytes adhered to the following characteristics: presence of metaphase II, lack of contact between cumulus cells and oocyte, absence of rough endoplasmic reticulum and Golgi complexes, peripheral location of cortical...

Ultrastructural changes of the UV-irradiated micronucleus in vegetative cells of Paramecium bursaria and its functional importance

Energy Technology Data Exchange (ETDEWEB)

Borkhsenius, O.N.; Fokin, S.I. (Leningradskij Gosudarstvennyj Univ. (USSR). Biologicheskij Nauchno-Issledovatel' skij Inst.)

1982-01-01

Ultrastructural micronucleus (MI) changes of vegetative cells in Paramecium bursaria in 0.5-7 h after MI ultraviolet irradiation and cell posterity with irradiated MI after different periods (2.6 and 30 days, three years) after ultraviolet irradiation have been studied. It is established that MI irradiation at a dose of 306J/m/sup 2/ doesn't result in its loss in postradiation generations however in posterity MI considerable ultrastructural changes occur. In two days after operation the shell of descendant MI of irradiated Paramecium bursaria forms multiple blades; small chromatin blocks considerably increase in sizes and, as a rule, occupy the central position in a nucleus. During later periods after irradiation (6 days) density of chromatin elements in MI begins to change. By the 30th day in MI fine-fibrillar karyoplasm detected are only not numerous chromatin structures scattered in disorder. The results obtained point to the existence of the ''cryptic'' type MIs are not revealed at the light-optical level but preserved in a series of postradiation generations. The presence of such MIs in viable cultures of P. bursaria confirms indirectly MI significance in vegetatic life of P. bursaria.

Ultrastructural changes of the UV-irradiated micronucleus in vegetative cells of paramecium bursaria and its functional importance

International Nuclear Information System (INIS)

Borkhsenius, O.N.; Fokin, S.I.

1982-01-01

Ultrastructural micronucleus (MI) changes of vegetative cells in Paramecium bursaria in 0.5-7 h after MI ultraviolet irradiation and cell posterity with irradiated MI after different periods (2.6 and 30 days, three years) after ultraviolet irradiation have been studied. It is established that MI irradiation at a dose of 306J/m 2 doesn't result in its loss in postradiation generations however in posterity MI considerable ultrastructural changes occur. In two days after operation the shell of descendant MI of irradiated Paramecium bursaria forms multiple blades; small chromatin blocks considerably increase in sizes and, as a rule, occupy the central position in a nucleus. During later periods afeter irradiation (6 days) density of chromatin elements in MI begins to change. By the 30-st day in MI fine-fibrillar karyoplasm detected are only not numerous chromatin structures scattered in disorder. The results obtained point to the existence of the ''cryptic'' type MIs are not revealed at the light-optical level but preserved in a series of postradiation generations. The presence of such MIs in viable cultures of P. bursaria confirms indirectly MI significance in vegetatic life of P. bursaria

An ultrastructural and immunocytochemical study of a rare genetic sperm tail defect that causes infertility in humans.

Science.gov (United States)

Baccetti, Baccio; Bruni, Emanuele; Gambera, Laura; Moretti, Elena; Piomboni, Paola

2004-08-01

To characterize and describe the ontogenesis of a rare flagellar defect affecting the whole sperm population of a sterile man. Case report. Regional referral center for male infertility in Siena, Italy. A 28-year-old man with severe asthenozoospermia. Physical and hormonal assays, semen analysis, and testicular biopsy. Semen samples and testicular biopsies were analyzed by light and transmission electron microscopy; immunocytochemical study with anti-beta-tubulin and anti-AKAP 82 antibodies was performed to detect the presence and distribution of proteins. Ultrastructural analysis of ejaculated spermatozoa and testicular biopsy revealed absence of the fibrous sheath in the principal-piece region of the tail. Fibrous sheath-like structures were observed in cytoplasmic residues and residual bodies released by spermatids in the seminiferous epithelium. Other anomalies observed were supplementary axonemes and mitochondrial helix elongation. These features were confirmed by immunocytochemical staining. This rare sperm tail defect, characterized by absence of the fibrous sheath, presence of supplementary axonemes, and an abnormally elongated midpiece, originates in the seminiferous tubules during spermiogenesis, as detected in testicular biopsy sections. These defects occur in the whole sperm population, and therefore a genetic origin could be suggested.

Ultrastructure, biology, and phylogenetic relationships of kinorhyncha.

Science.gov (United States)

Neuhaus, Birger; Higgins, Robert P

2002-07-01

The article summarizes current knowledge mainly about the (functional) morphology and ultrastructure, but also about the biology, development, and evolution of the Kinorhyncha. The Kinorhyncha are microscopic, bilaterally symmetrical, exclusively free-living, benthic, marine animals and ecologically part of the meiofauna. They occur throughout the world from the intertidal to the deep sea, generally in sediments but sometimes associated with plants or other animals. From adult stages 141 species are known, but 38 species have been described from juvenile stages. The trunk is arranged into 11 segments as evidenced by cuticular plates, sensory spots, setae or spines, nervous system, musculature, and subcuticular glands. The ultrastructure of several organ systems and the postembryonic development are known for very few species. Almost no data are available about the embryology and only a single gene has been sequenced for a single species. The phylogenetic relationships within Kinorhyncha are unresolved. Priapulida, Loricifera, and Kinorhyncha are grouped together as Scalidophora, but arguments are found for every possible sistergroup relationship within this taxon. The recently published Ecdysozoa hypothesis suggests a closer relationship of the Scalidophora, Nematoda, Nematomorpha, Tardigrada, Onychophora, and Arthropoda.

Cytological and ultrastructural preservation in Eocene Metasequoia leaves from the Canadian high Arctic

Energy Technology Data Exchange (ETDEWEB)

Schoenhut, K.; Vann, D.R.; LePage, B.A. [University of Pennsylvania, Philadelphia, PA (United States). Dept. of Earth & Environmental Science

2004-06-01

The ultrastructural examination by transmission electron microscopy of 45-million-year-old mummified leaves of Metasequoia extracted from the Upper Coal member of the Buchanan Lake Formation in Napartulik on Axel Heiberg Island revealed the preservation of intact chloroplasts and chloroplast components. Abundant tanniferous cell inclusions may indicate that the 3-mo period of constant daylight during the Arctic summer induced high concentrations of tannins in the leaf tissues, which may have arrested microbial degradation of the litter. Quantified differences in the extent of chloroplast preservation through a vertical section of the lignite suggest that short-term shifts in the depositional environment took place, perhaps influencing the exposure of the leaf tissues to conditions that would either promote or inhibit decomposition.

Cytological and ultrastructural preservation in Eocene Metasequoia leaves from the Canadian High Arctic.

Science.gov (United States)

Schoenhut, Karimah; Vann, David R; Lepage, Ben A

2004-06-01

The ultrastructural examination by transmission electron microscopy of 45-million-year-old mummified leaves of Metasequoia extracted from the Upper Coal member of the Buchanan Lake Formation in Napartulik on Axel Heiberg Island revealed the preservation of intact chloroplasts and chloroplast components. Abundant tanniferous cell inclusions may indicate that the 3-mo period of constant daylight during the Artic summer induced high concentrations of tannins in the leaf tissues, which may have arrested microbial degradation of the litter. Quantified differences in the extent of chloroplast preservation through a vertical section of the lignite suggest that short-term shifts in the depositional environment took place, perhaps influencing the exposure of the leaf tissues to conditions that would either promote or inhibit decomposition.

Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates.

Science.gov (United States)

Rosset, Sabrina; Wiedenmann, Jörg; Reed, Adam J; D'Angelo, Cecilia

2017-05-15

Enrichment of reef environments with dissolved inorganic nutrients is considered a major threat to the survival of corals living in symbiosis with dinoflagellates (Symbiodinium sp.). We argue, however, that the direct negative effects on the symbiosis are not necessarily caused by the nutrient enrichment itself but by the phosphorus starvation of the algal symbionts that can be caused by skewed nitrogen (N) to phosphorus (P) ratios. We exposed corals to imbalanced N:P ratios in long-term experiments and found that the undersupply of phosphate severely disturbed the symbiosis, indicated by the loss of coral biomass, malfunctioning of algal photosynthesis and bleaching of the corals. In contrast, the corals tolerated an undersupply with nitrogen at high phosphate concentrations without negative effects on symbiont photosynthesis, suggesting a better adaptation to nitrogen limitation. Transmission electron microscopy analysis revealed that the signatures of ultrastructural biomarkers represent versatile tools for the classification of nutrient stress in symbiotic algae. Notably, high N:P ratios in the water were clearly identified by the accumulation of uric acid crystals. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Label-free visualization of ultrastructural features of artificial synapses via cryo-EM.

Science.gov (United States)

Gopalakrishnan, Gopakumar; Yam, Patricia T; Madwar, Carolin; Bostina, Mihnea; Rouiller, Isabelle; Colman, David R; Lennox, R Bruce

2011-12-21

The ultrastructural details of presynapses formed between artificial substrates of submicrometer silica beads and hippocampal neurons are visualized via cryo-electron microscopy (cryo-EM). The silica beads are derivatized by poly-d-lysine or lipid bilayers. Molecular features known to exist at presynapses are clearly present at these artificial synapses, as visualized by cryo-EM. Key synaptic features such as the membrane contact area at synaptic junctions, the presynaptic bouton containing presynaptic vesicles, as well as microtubular structures can be identified. This is the first report of the direct, label-free observation of ultrastructural details of artificial synapses.

Testicular immunohistochemical and Ultrastructural changes associated with chronic cholestasis in rats: Effect of ursodeoxycholic acid.

Science.gov (United States)

Mahmoud, Yomna I

2015-09-01

Testicular atrophy has been commonly reported in patients with chronic liver diseases. Ursodeoxycholic acid is the most widely used drug for the treatment of many liver diseases. However, its effect on testicular ultrastructure associated with chronic cholestasis has never been studied. Thus, this study aimed to assess how chronic obstructive jaundice affects the testicular ultrastructure and whether it affects the androgen receptor or the proliferating cell nuclear antigen. The role of ursodeoxycholic acid was also investigated. Cholestasis was induced by bile duct ligation. Samples were collected 4weeks postoperative. Testicular changes were assessed using immunohistochemistry and transmission electron microscopy. Chronic cholestasis resulted in testicular atrophy evidenced by shrinkage and deformation of seminiferous tubules, thickening of peritubular boundaries, vacuolation, disorganization of germ cells, and maturation arrest. This was accompanied by decreased immunoreactivity of androgen receptors and proliferating cell nuclear antigen. Administration of ursodeoxycholic acid improved the testicular morphology and reversed cholestasis-induced immunohistochemical and ultrastructural changes. Ursodeoxycholic acid can improve the testicular ultrastructure and restore the spermatogenic process in rats with chronic cholestasis. These findings support the clinical application of ursodeoxycholic acid in cholestatic patients especially those with hypogonadism. Copyright © 2015. Published by Elsevier Inc.

Ultrastructural and Histochemical Characterization of the Zebra Mussel Adhesive Apparatus

Science.gov (United States)

Farsad, Nikrooz

Since their accidental introduction into the Great Lakes in mid- to late-1980s, the freshwater zebra mussels, Dreissena polymorpha, have colonized most lakes and waterways across eastern North America. Their rapid spread is partly attributed to their ability to tenaciously attach to hard substrates via an adhesive apparatus called the byssus, resulting in serious environmental and economic impacts. A detailed ultrastructural study of the byssus revealed a 10 nm adhesive layer at the attachment interface. Distributions of the main adhesive amino acid, 3,4-dihydroxyphenylalanine (DOPA), and its oxidizing (cross-linking) enzyme, catechol oxidase, were determined histochemically. It was found that, upon aging, DOPA levels remained high in the portion of the byssus closest to the interface, consistent with an adhesive role. In contrast, reduced levels of DOPA corresponded well with high levels of catechol oxidase in the load-bearing component of the byssus, presumably forming cross-links and increasing the cohesive strength.

Ultrastructure of medial rectus muscles in patients with intermittent exotropia.

Science.gov (United States)

Yao, J; Wang, X; Ren, H; Liu, G; Lu, P

2016-01-01

PURPOSE To study the ultrastructure of the medial rectus in patients with intermittent exotropia at different ages.PATIENTS AND METHODS The medial recti were harvested surgically from 20 patients with intermittent exotropia. Patients were divided into adolescent (age18 years, n=10). The normal control group included five patients without strabismus and undergoing eye enucleation. Hematoxylin and eosin staining and transmission electron microscopy were used to visualize the medial recti. Western blot was used to determine the levels of myosin and actin.RESULTS Varying fiber thickness, atrophy, and misalignment of the medial recti were visualized under optical microscope in patients with exotropia. Electron microscopy revealed sarcomere destruction, myofilament disintegration, unclear dark and light bands, collagen proliferation, and fibrosis. The adolescent group manifested significantly higher levels of myosin and actin than the adult group (Pstronger contraction of the medial recti compared with older patients. Our findings suggest that childhood was the appropriate time for surgery as the benefit of the intervention was better than in adulthood.

Determination of leukemia-associated gene rearrangements and ultrastructural changes in Chernobyl accident liquidators blood leukocytes long term after radiation exposure

International Nuclear Information System (INIS)

Butenko, Z.A.; Smirnova, I.A.; Yanok, E.A.; Kishinskaya, E.G.; Zak, K.P.; Afanas'eva, V.V.; Mikhajlovskaya, Eh.V.

1997-01-01

The results of ultrastructural and molecular-genetic investigations of blood cells from 120 liquidators 7-10 years after Chernobyl accident with the total exposure radiation doses ranging from 5.1 to 75.0 cGy are presented. Electron microscopic studies revealed marked changes in ultrastructure of neutrophils nuclei - hyper segmentation, whimsical prominences, loops, swelling and destruction of cytoplasmic granules. There was an increase in the number of 'aberrant' forms of lymphocytes with disturbed structure of chromatin, additional nuclei and changed membrane contour. Structural polymorphism of the leukemia associated bcr and ribosomal RNA (rRNA) genes were studied using Southern blot hybridization. Allelic polymorphism of bcr gene with characteristic for chronic myeloid leukemia allele distribution and rearrangements of eRNA genes were detected in 11.5% of accident liquidators. This data point out to structure-functional leucocyte changes and possibility of arising leukemia associated gene rearrangements in blood cells of some liquidators many years after the exposure to radiation and serve for determination of group at risk of oncohematological diseases

Prototheca zopfii Induced Ultrastructural Features Associated with Apoptosis in Bovine Mammary Epithelial Cells

Directory of Open Access Journals (Sweden)

Muhammad Shahid

2017-07-01

TEM. The findings of the current study revealed that genotype-II has the capability to invade and survive within the bMECs, thus imparting significant damages to the mammary cells which result in apoptosis. This study represents the first insights into the pathomorphological and ultrastructure features of apoptosis in bMECs induced by P. zopfii genotype-II.

The ultrastructure of the midgut epithelium in millipedes (Myriapoda, Diplopoda)

Czech Academy of Sciences Publication Activity Database

Sosinka, A.; Rost-Roszkowska, M.M.; Vilímová, J.; Tajovský, Karel; Kszuk-Jendrysik, M.; Chajec, Ł.; Sonakowska, L.; Kamińska, K.; Hyra, M.; Poprawa, I.

2014-01-01

Roč. 43, č. 5 (2014), s. 477-492 ISSN 1467-8039 Institutional support: RVO:60077344 Keywords : digestive cells * midgut epithelium * millipedes * regenerative cells * secretory cells * ultrastructure Subject RIV: EG - Zoology Impact factor: 1.650, year: 2014

Ultrastructural examination of skin biopsies may assist in diagnosing mitochondrial cytopathy when muscle biopsies yield negative results.

Science.gov (United States)

McAfee, John L; Warren, Christine B; Prayson, Richard A

2017-08-01

Ultrastructural evaluation of skin biopsies has been utilized for diagnosis of mitochondrial disease. This study investigates how frequently skin biopsies reveal mitochondrial abnormalities, correlates skin and muscle biopsy findings, and describes clinical diagnoses rendered following the evaluation. A retrospective review of surgical pathology reports from 1990 to 2015 identified skin biopsies examined by electron microscopy for suspected metabolic disease. A total of 630 biopsies were included from 615 patients. Of these patients, 178 also underwent a muscle biopsy. Of the 630 skin biopsies, 75 (12%) showed ultrastructural abnormalities and 34 (5%) specifically showed mitochondrial abnormalities including increased size (n=27), reduced or abnormal cristae (n=23), dense matrices (n=20), and increased number (n=8). Additional findings included lysosomal abnormalities (n=13), lipid accumulation (n=2) or glycogen accumulation (n=1). Of the 34 patients with mitochondrial abnormalities on skin biopsy, 20 also had muscle biopsies performed and nine showed abnormalities suggestive of a mitochondrial disorder including absent cytochrome oxidase staining (n=2), increased subsarcolemmal NADH, SDH, or cytochrome oxidase staining (n=1), or ultrastructural findings including large mitochondrial size (n=5), abnormal mitochondrial structure (n=5), and increased mitochondrial number (n=4). The most common presenting symptoms were intellectual disability (n=13), seizures (n=12), encephalopathy (n=9), and gastrointestinal disturbances (n=9). At last known follow-up, 12 patients had a definitive diagnosis of a mitochondrial disorder. One patient each had Complex I deficiency, Complex III deficiency, Charcot-Marie-Tooth disease, pyruvate dehydrogenase deficiency, and Phelan-McDermid syndrome. Our results suggest that skin biopsy sometimes yields diagnostic clues suggestive of a mitochondrial cytopathy in cases with a negative muscle biopsy. Copyright © 2017 Elsevier Inc. All rights

Ultrastructural changes and the distribution of arabinogalactan proteins during somatic embryogenesis of banana (Musa spp. AAA cv. 'Yueyoukang 1').

Science.gov (United States)

Pan, Xiao; Yang, Xiao; Lin, Guimei; Zou, Ru; Chen, Houbin; Samaj, Jozef; Xu, Chunxiang

2011-08-01

A better understanding of somatic embryogenesis in banana (Musa spp.) may provide a practical way to improve regeneration of banana plants. In this study, we applied scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to visualize the ultrastructural changes during somatic embryogenesis of banana (Musa AAA cv. 'Yueyoukang 1'). We also used histological and immunohistochemical techniques with 16 monoclonal antibodies to study the spatial distribution and cellular/subcellular localization of different arabinogalactan protein (AGP) components of the cell wall during somatic embryogenesis. Histological study with periodic acid-Schiff staining documented diverse embryogenic stages from embryogenic cells (ECs) to the late embryos. SEM revealed a mesh-like structure on the surface of proembryos which represented an early structural marker of somatic embryogenesis. TEM showed that ECs were rich in juvenile mitochondria, endoplasmic reticulum and Golgi stacks. Cells in proembryos and early globular embryos resembled ECs, but they were more vacuolated, showed more regular nuclei and slightly more developed organelles. Immunocytochemical study revealed that the signal of most AGP epitopes was stronger in starch-rich cells when compared with typical ECs. The main AGP component in the extracellular matrix surface network of banana proembryos was the MAC204 epitope. Later, AGP immunolabelling patterns varied with the developmental stages of the embryos. These results about developmental regulation of AGP epitopes along with developmental changes in the ultrastructure of cells are providing new insights into the somatic embryogenesis of banana. Copyright © Physiologia Plantarum 2011.

Ultrastructural Morphology of Sperm from Human Globozoospermia

Directory of Open Access Journals (Sweden)

Giuseppe Ricci

2015-01-01

Full Text Available Globozoospermia is a rare disorder characterized by the presence of sperm with round head, lacking acrosome. Coiling tail around the nucleus has been reported since early human studies, but no specific significance has conferred it. By contrast, studies on animal models suggest that coiling tail around the nucleus could represent a crucial step of defective spermatogenesis, resulting in round-headed sperm. No observations, so far, support the transfer of this hypothesis to human globozoospermia. The purpose of this work was to compare ultrastructural morphology of human and mouse model globozoospermic sperm. Sperm have been investigated by using scanning and transmission electron microscopy. The images that we obtained show significant similarities to those described in GOPC knockout mice, an animal model of globozoospermia. By using this model as reference, we were able to identify the probable steps of the tail coiling process in human globozoospermia. Although we have no evidence that there is the same pathophysiology in man and knocked-out mouse, the similarities between these ultrastructural observations in human and those in the experimental model are very suggestive. This is the first demonstration of the existence of relevant morphological homologies between the tail coiling in animal model and human globozoospermia.

Dermal Ultrastructure in Low Beighton Score Members of 17 Families with Hypermobile-Type Ehlers-Danlos Syndrome

Science.gov (United States)

Hermanns-Lê, Trinh; Reginster, Marie-Annick; Piérard-Franchimont, Claudine; Delvenne, Philippe; Piérard, Gérald E.; Manicourt, Daniel

2012-01-01

The distinction between the Ehlers-Danlos syndrome hypermobile type (EDSH) and the benign joint hypermobility syndrome (BJHS) is unclear. The aim of the present study was to compare skin ultrastructural abnormalities of EDSH and BJHS among different families. Skin of 23 EDSH, 27 BJHS, and 41 asymptomatic subjects from 17 families was examined using transmission electron microscopy. Similar ultrastructural abnormalities were found irrespective of the Beighton score. Flower-like collagen fibrils represented the key change and elastic fibers were altered as well. Beighton score is a clinical parameter rating joint mobility that appeared unrelated to quantitative and qualitative collagen ultrastructural alterations in the skin. Some EDSH family members fit with BJHS diagnosis. BJHS possibly represents a mild variant of EDSH. PMID:23091361

Dermal Ultrastructure in Low Beighton Score Members of 17 Families with Hypermobile-Type Ehlers-Danlos Syndrome

Directory of Open Access Journals (Sweden)

Trinh Hermanns-Lê

2012-01-01

Full Text Available The distinction between the Ehlers-Danlos syndrome hypermobile type (EDSH and the benign joint hypermobility syndrome (BJHS is unclear. The aim of the present study was to compare skin ultrastructural abnormalities of EDSH and BJHS among different families. Skin of 23 EDSH, 27 BJHS, and 41 asymptomatic subjects from 17 families was examined using transmission electron microscopy. Similar ultrastructural abnormalities were found irrespective of the Beighton score. Flower-like collagen fibrils represented the key change and elastic fibers were altered as well. Beighton score is a clinical parameter rating joint mobility that appeared unrelated to quantitative and qualitative collagen ultrastructural alterations in the skin. Some EDSH family members fit with BJHS diagnosis. BJHS possibly represents a mild variant of EDSH.

Ultrastructure of respiratory tract epithelium following irradiation or application of cytostatics

International Nuclear Information System (INIS)

Konradova, V.; Smelhaus, V.; Kanta, J.

1988-01-01

The ultrastructure was studied of the large bronchi epithelium in 3 patients with malignant tumors where signs of pulmonary fibrosis were found following irradiation and combined therapy. In 2 patients, pseudostratified cylindrical epithelium was observed with signs of pathological alteration, in the third patient an altered pseudostratified cylindrical epithelium with ultrastructural signs of commencing reconstructure into stratified squamous epithelium. The findings in the respiratory track epithelium of the patients were similar to those observed in a group of children with chronic or relapsing bronchitis and bronchopneumonia. The findings show marked disturbance of the ciliary border caused by reduction in the number of kinocilia which is associated with an impairment of the self-cleaning capacity of epithelium. (author). 1 tab., 10 refs

Stereomicroscopic and ultrastructural characterization of propionitrile-induced duodenal ulcer in the rat

DEFF Research Database (Denmark)

Poulsen, Steen Seier

1978-01-01

Acute duodenal ulcer produced by subcutaneous injection of propionitrile in rats was studied by stereo, light, and electron microscopy in order to gain insight into the localization and mechanism of initial cell injury. Stereomicroscopy revealed an initial fissuring and splitting of the tips...... of the villus folds within 4 hours after two injections of propionitrile. This was followed by sloughing of the epithelium, shortening and effacement of the villus folds, and within 24 hours the appearance of discrete ulcers in the mucosa of the proximal duodenum. In most of the rats, two ulcers developed......: the first and larger ulcer was on the antimesenteric side of the duodenum, and the other, a small and more superficial one, was on the opposite wall. Ultrastructural lesions appeared in the absorptive epithelial cells of the proximal duodenum within 5 hours following a single dose of propionitrile...

Ultrastructure of interstitial cells in subserosa of human colon

DEFF Research Database (Denmark)

Rumessen, Jüri Johannes; Vanderwinden, Jean-Marie; Hansen, Alastair

2013-01-01

vesicles) were prominent. The IC-SS ultrastructure was different from that of FLC in the longitudinal layer, which had no caveolae and fewer intermediate filaments. Peg-and-socket junctions between IC-SS and between IC-SS and muscle cells were present, and IC-SS processes had close, selective appositions...

Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, J. [Departamento de Microbiologia e Inmunologia Veterinaria, Universidad Federal Rural de Rio de Janeiro (UFRRJ) (Brazil); Cavaglieri, L., E-mail: lcavaglieri@arnet.com.a [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Vital, H. [Centro Tecnologico do Exercito (CTEx), Secao de Defesa Nuclear, Rio de Janeiro (Brazil); Cristofolini, A.; Merkis, C. [Departamento de Microscopia Electronica, Universidad Nacional de Rio Cuarto. Ruta 36 km 601 (5800) Rio Cuarto (Argentina); Astoreca, A. [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Orlando, J.; Caru, M. [Departamento de Ciencias Ecologicas, Facultad de Ciencias, Universidad de Chile, Santiago (Chile); Dalcero, A. [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Rosa, C.A.R. [Departamento de Microbiologia e Inmunologia Veterinaria, Universidad Federal Rural de Rio de Janeiro (UFRRJ) (Brazil); Member of Consejo Nacional de Pesquisas (CNPq) (Brazil)

2011-05-15

The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B{sub 1} and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

International Nuclear Information System (INIS)

Ribeiro, J.; Cavaglieri, L.; Vital, H.; Cristofolini, A.; Merkis, C.; Astoreca, A.; Orlando, J.; Caru, M.; Dalcero, A.; Rosa, C.A.R.

2011-01-01

The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B 1 and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

Ultrastructural changes in the sublingual salivary gland of prenatal buffalo (Bubalus bubalis

Directory of Open Access Journals (Sweden)

A. D. Singh

2016-03-01

Full Text Available Aim: The present study was aimed to elucidate ultrastructural changes in the development of sublingual salivary gland of buffalo during prenatal life. Materials and Methods: The study was carried out on sublingual salivary gland of 36 buffalo fetuses ranging from 13.2 cm curved crown-rump length (CVRL (88th day to full term. The fetuses were categorized into three groups based on their CVRL. Results: The cells lining the terminal tubules were undifferentiated with poorly developed cytoplasmic organelles but lacked secretory granules (SGs at 13.2 cm CVRL (88th day. The SGs appeared first in the form of membrane-bound secretory vesicles with homogeneous electron-dense as well as electron-lucent contents at 21.2 cm CVRL (122nd day; however, mucous acinar cells contained electron-lucent granules, while serous secretory cells as well as serous demilunes showed electron-dense granules at 34 cm CVRL (150th day of prenatal life. At 53.5 cm CVRL (194th day, both mucous and serous acini were differentiated by the density of SGs. Conclusion: The cytoplasm of acinar cells was filled with mitochondria, rough endoplasmic reticulum, and Golgi profiles in mid and late fetal age groups. The SGs were increased in number during the late fetal age group. The myoepithelial cells (MECs were located at the base of the acinar cells as well as intercalated and striated ducts and were stellate in shape. The ultrastructure of MEC revealed a parallel stream of myofilaments in the cytoplasm and its processes. The mucous cells were predominantly present in the sublingual salivary gland and were pyramidal in shape.

Synthesis and ultrastructure of plate-like apatite single crystals as a model for tooth enamel

International Nuclear Information System (INIS)

Zhuang, Zhi; Yoshimura, Hideyuki; Aizawa, Mamoru

2013-01-01

Hydroxyapatite (HAp) is an inorganic constituent compound of human bones and teeth, with superior biocompatibility and bioactivity characteristics. Its crystal structure is hexagonal, characterized by a(b)- and c-planes. In vertebrate long bones, HAp crystals have a c-axis orientation, while in tooth enamel, they have an a(b)-axis orientation. Many methods can be used to synthesize c-axis oriented HAp single crystals; however, to the best of our knowledge, there have been no reports on a synthesis method for a(b)-axis oriented HAp single crystals. In this study, we successfully synthesized plate-like HAp crystals at the air–liquid interface of a starting solution via an enzyme reaction of urea with urease. Crystal phase analysis and ultrastructure observations were carried out, and the results indicated that the particles were single crystals, with almost the same a(b)-axis orientation as tooth enamel. It is hoped that by utilizing their unique surface charge and atomic arrangement, the resulting particles can be used as a high-performance biomaterial, capable of adsorbing bio-related substances and a model for tooth enamel. - Highlights: ► Synthesis of plate-like hydroxyapatite crystals at air–liquid interface ► Ultrastructural analysis of plate-like hydroxyapatite crystals ► Plate-like hydroxyapatite single crystals with a high a(b)-axis orientation ► Plate-like hydroxyapatite single crystals as a model for tooth enamel

Synthesis and ultrastructure of plate-like apatite single crystals as a model for tooth enamel

Energy Technology Data Exchange (ETDEWEB)

Zhuang, Zhi, E-mail: zhuang@meiji.ac.jp [Department of Applied Chemistry, School of Science and Technology, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Yoshimura, Hideyuki, E-mail: hyoshi@isc.meiji.ac.jp [Department of Physics, School of Science and Technology, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Aizawa, Mamoru, E-mail: mamorua@isc.meiji.ac.jp [Department of Applied Chemistry, School of Science and Technology, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan)

2013-07-01

Hydroxyapatite (HAp) is an inorganic constituent compound of human bones and teeth, with superior biocompatibility and bioactivity characteristics. Its crystal structure is hexagonal, characterized by a(b)- and c-planes. In vertebrate long bones, HAp crystals have a c-axis orientation, while in tooth enamel, they have an a(b)-axis orientation. Many methods can be used to synthesize c-axis oriented HAp single crystals; however, to the best of our knowledge, there have been no reports on a synthesis method for a(b)-axis oriented HAp single crystals. In this study, we successfully synthesized plate-like HAp crystals at the air–liquid interface of a starting solution via an enzyme reaction of urea with urease. Crystal phase analysis and ultrastructure observations were carried out, and the results indicated that the particles were single crystals, with almost the same a(b)-axis orientation as tooth enamel. It is hoped that by utilizing their unique surface charge and atomic arrangement, the resulting particles can be used as a high-performance biomaterial, capable of adsorbing bio-related substances and a model for tooth enamel. - Highlights: ► Synthesis of plate-like hydroxyapatite crystals at air–liquid interface ► Ultrastructural analysis of plate-like hydroxyapatite crystals ► Plate-like hydroxyapatite single crystals with a high a(b)-axis orientation ► Plate-like hydroxyapatite single crystals as a model for tooth enamel.

Surface ultrastructure of third-instar Megaselia scalaris (Diptera: Phoridae

Directory of Open Access Journals (Sweden)

Sukontason Kabkaew L

2002-01-01

Full Text Available We describe some ultrastructure of the third-instar Megaselia scalaris (Diptera: Phoridae using scanning electron microscopy, with the cephalic segment, anterior spiracle and posterior spiracle being emphasized. This study provides the taxonomic information of this larval species, which may be useful to differentiate from other closely-related species.

Gene expression profiling in equine polysaccharide storage myopathy revealed inflammation, glycogenesis inhibition, hypoxia and mitochondrial dysfunctions

Directory of Open Access Journals (Sweden)

Benech Philippe

2009-08-01

Full Text Available Abstract Background Several cases of myopathies have been observed in the horse Norman Cob breed. Muscle histology examinations revealed that some families suffer from a polysaccharide storage myopathy (PSSM. It is assumed that a gene expression signature related to PSSM should be observed at the transcriptional level because the glycogen storage disease could also be linked to other dysfunctions in gene regulation. Thus, the functional genomic approach could be conducted in order to provide new knowledge about the metabolic disorders related to PSSM. We propose exploring the PSSM muscle fiber metabolic disorders by measuring gene expression in relationship with the histological phenotype. Results Genotypying analysis of GYS1 mutation revealed 2 homozygous (AA and 5 heterozygous (GA PSSM horses. In the PSSM muscles, histological data revealed PAS positive amylase resistant abnormal polysaccharides, inflammation, necrosis, and lipomatosis and active regeneration of fibers. Ultrastructural evaluation revealed a decrease of mitochondrial number and structural disorders. Extensive accumulation of an abnormal polysaccharide displaced and partially replaced mitochondria and myofibrils. The severity of the disease was higher in the two homozygous PSSM horses. Gene expression analysis revealed 129 genes significantly modulated (p Conclusion The main disorders observed in PSSM muscles could be related to mitochondrial dysfunctions, glycogenesis inhibition and the chronic hypoxia of the PSSM muscles.

Pancreatic PEComa: a case report with ultrastructural localization of HMB-45 within melanosomes.

Science.gov (United States)

Finzi, Giovanna; Micello, Donata; Wizemann, Giorgio; Sessa, Fausto; Capella, Carlo

2012-04-01

PEComas (perivascular epithelioid cell tumors) represent a group of mesenchymal neoplasms showing characteristic morphologic, immunohistochemical, ultrastructural, and genetic features. These neoplasms are usually considered benign, being often well circumscribed by a thin capsule and showing scarce atypia. However, in some cases, they show local invasion and multiple metastases and cause the patient's death. PEComas have been found in many locations, but only 7 cases have been described in the pancreas to date. Here, the authors report an additional case of this rare neoplasm and demonstrate the HMB-45 immunoreactivity of melanosomes or premelanosomes at the ultrastructural level.

Ultrastructural and histological findings on examination of skin in osteogenesis imperfecta: a novel study.

Science.gov (United States)

Balasubramanian, Meena; Wagner, Bart E; Peres, Luiz C; Sobey, Glenda J; Parker, Michael J; Dalton, Ann; Arundel, Paul; Bishop, Nicholas J

2015-04-01

Osteogenesis imperfecta (OI) is a heterogeneous group of inherited disorders of bone formation, resulting in low bone mass and an increased propensity for fractures. It is a variable condition with a range of clinical severities. The histological and ultrastructural findings in the skin of patients with OI have not been described in detail in the previously published literature. Although protein analysis of cultured fibroblasts has historically been used in the diagnostic work-up of OI patients, other aspects of skin examination are not routinely performed as part of the diagnostic pathway in patients with OI. The aims of this study were to perform histological and ultrastructural examination of skin biopsies in patients with OI. This was to identify common and distinguishing features in the numerous genetically distinct subtypes of OI and compare the findings with those in patients who did not present with fractures, and to enable the use of the results thus obtained to aid in the diagnostic work-up of patients with OI. As part of a larger research study set-up to identify clinical features and natural history in patients with atypical features of OI, skin biopsy and examination (histology and electron microscopy) were undertaken. Genetic analysis and ancillary investigations were also performed to identify similarities within this group and to differentiate this group from the 'normal' population. At the end of this study, we were able to demonstrate that the histological and electron microscopic findings on a skin biopsy may be an indicator of the likelihood of identifying a pathogenic mutation in type 1 collagen genes. This is because patients with specific findings on examination, such as elastic fibre area fraction (on histological analysis), collagen fibril diameter variability, deviation from the expected mean and collagen flowers (on electron microscopy), are more likely to be positive on genetic analyses. This has, in turn, provided more insight into the

Ultrastructure of sheep primordial follicles cultured in the presence of indol acetic acid, EGF, and FSH

DEFF Research Database (Denmark)

Andrade, Evelyn Rabelo; Hyttel, Poul; Landim-Alvarenga, Fernanda Da Cruz

2011-01-01

The aim of this study was to investigate the ultrastructural characteristics of primordial follicles after culturing of sheep ovarian cortical slices in the presence of indol acetic acid (IAA), Epidermal Growth Factor (EGF), and FSH. To evaluate ultrastructure of primordial follicles cultured...... in MEM (control) or in MEM containing IAA, EGF, and FSH, fragments of cultured tissue were processes for transmission electron microscopy. Except in the control, primordial follicles cultured in supplemented media for 6¿d were ultrastructurally normal. They had oocyte with intact nucleus...... and the cytoplasm contained heterogeneous-sized lipid droplets and numerous round or elongated mitochondria with intact parallel cristae were observed. Rough endoplasmic reticulum (RER) was rarely found. The granulosa cells cytoplasm contained a great number of mitochondria and abundant RER. In conclusion...

Structural and Ultrastructural Analysis of Cerebral Cortex, Cerebellum, and Hypothalamus from Diabetic Rats

Directory of Open Access Journals (Sweden)

Juan P. Hernández-Fonseca

2009-01-01

Full Text Available Autonomic and peripheral neuropathies are well-described complications in diabetes. Diabetes mellitus is also associated to central nervous system damage. This little-known complication is characterized by impairment of brain functions and electrophysiological changes associated with neurochemical and structural abnormalities. The purpose of this study was to investigate brain structural and ultrastructural changes in rats with streptozotocin-induced diabetes. Cerebral cortex, hypothalamus, and cerebellum were obtained from controls and 8 weeks diabetic rats. Light and electron microscope studies showed degenerative changes of neurons and glia, perivascular and mitochondrial swelling, disarrangement of myelin sheath, increased area of myelinated axons, presynaptic vesicle dispersion in swollen axonal boutoms, fragmentation of neurofilaments, and oligodendrocyte abnormalities. In addition, depressive mood was observed in diabetic animals. The brain morphological alterations observed in diabetic animals could be related to brain pathologic process leading to abnormal function, cellular death, and depressive behavioral.

Effect of superlarge dose of gamma radiation on the rat cerebral cortex (ultrastructural aspects)

International Nuclear Information System (INIS)

Abdrakhmanov, A.A.; AN Kazakhskoj SSR, Alma-Ata

1988-01-01

Puberal Wistar line mall rats (180-210 g) were subjected to single whole-body gamma irradiation with 150 Gy dose and 75 Gy/min dose rate. Electron-microscopic investigation into dynamics of sensory-motor cortex ultrastructural changes during 24 hours after irradiation is conducted. Along with destructive changes compensator-reduction processes are developed in brain tissue at this period. Already during the first hours after irradiation the neutron ultrastructure change dynamics has been determined, alongside with direct radiation effect, by indirect effects juries of neuroglia and microcirculatory channel

Effect of superlarge dose of gamma radiation on the rat cerebral cortex (ultrastructural aspects)

Energy Technology Data Exchange (ETDEWEB)

Abdrakhmanov, A A

1988-06-01

Puberal Wistar line mall rats (180-210 g) were subjected to single whole-body gamma irradiation with 150 Gy dose and 75 Gy/min dose rate. Electron-microscopic investigation into dynamics of sensory-motor cortex ultrastructural changes during 24 hours after irradiation is conducted. Along with destructive changes compensator-reduction processes are developed in brain tissue at this period. Already during the first hours after irradiation the neutron ultrastructure change dynamics has been determined, alongside with direct radiation effect, by indirect effects juries of neuroglia and microcirculatory channel.

Quantitative Assessment of Ultrastructure and Light Scatter in Mouse Corneal Debridement Wounds

Science.gov (United States)

Boote, Craig; Du, Yiqin; Morgan, Sian; Harris, Jonathan; Kamma-Lorger, Christina S.; Hayes, Sally; Lathrop, Kira L.; Roh, Danny S.; Burrow, Michael K.; Hiller, Jennifer; Terrill, Nicholas J.; Funderburgh, James L.; Meek, Keith M.

2012-01-01

Purpose. The mouse has become an important wound healing model with which to study corneal fibrosis, a frequent complication of refractive surgery. The aim of the current study was to quantify changes in stromal ultrastructure and light scatter that characterize fibrosis in mouse corneal debridement wounds. Methods. Epithelial debridement wounds, with and without removal of basement membrane, were produced in C57BL/6 mice. Corneal opacity was measured using optical coherence tomography, and collagen diameter and matrix order were quantified by x-ray scattering. Electron microscopy was used to visualize proteoglycans. Quantitative PCR (Q-PCR) measured mRNA transcript levels for several quiescent and fibrotic markers. Results. Epithelial debridement without basement membrane disruption produced a significant increase in matrix disorder at 8 weeks, but minimal corneal opacity. In contrast, basement membrane penetration led to increases in light scatter, matrix disorder, and collagen diameter, accompanied by the appearance of abnormally large proteoglycans in the subepithelial stroma. This group also demonstrated upregulation of several quiescent and fibrotic markers 2 to 4 weeks after wounding. Conclusions. Fibrotic corneal wound healing in mice involves extensive changes to collagen and proteoglycan ultrastructure, consistent with deposition of opaque scar tissue. Epithelial basement membrane penetration is a deciding factor determining the degree of ultrastructural changes and resulting opacity. PMID:22467580

Ultrastructural dynamics of human reproduction, from ovulation to fertilization and early embryo development.

Science.gov (United States)

Familiari, Giuseppe; Heyn, Rosemarie; Relucenti, Michela; Nottola, Stefania A; Sathananthan, A Henry

2006-01-01

This study describes the updated, fine structure of human gametes, the human fertilization process, and human embryos, mainly derived from assisted reproductive technology (ART). As clearly shown, the ultrastructure of human reproduction is a peculiar multistep process, which differs in part from that of other mammalian models, having some unique features. Particular attention has been devoted to the (1) sperm ultrastructure, likely "Tygerberg (Kruger) strict morphology criteria"; (2) mature oocyte, in which the MII spindle is barrel shaped, anastral, and lacking centrioles; (3) three-dimensional microarchitecture of the zona pellucida with its unique supramolecular filamentous organization; (4) sperm-egg interactions with the peculiarity of the sperm centrosome that activates the egg and organizes the sperm aster and mitotic spindles of the embryo; and (5) presence of viable cumulus cells whose metabolic activity is closely related to egg and embryo behavior in in vitro as well as in vivo conditions, in a sort of extraovarian "microfollicular unit." Even if the ultrastructural morphodynamic features of human fertilization are well understood, our knowledge about in vivo fertilization is still very limited and the complex sequence of in vivo biological steps involved in human reproduction is only partially reproduced in current ART procedures.

Histochemical and ultrastructural studies on the calcareous corpuscles and eggs of Taenia taeniaeformis and Dipylidium caninum.

Science.gov (United States)

Khalifa, Refaat M A; Mazen, Nawal A M; Marawan, Aziza M A; Thabit, Hasnaa T M

2011-08-01

Calcareous corpuscles were noticed by several previous workers to be present in larval and adult cestodes without knowing their function. However, nothing was mentioned in the available literature about distribution of these corpuscles and their density, structure and composition in different parts of the body of different cestodes. Hence, in the present work, a comparative study of their distribution, density, histochemical and ultrastructural characters in different parts of the body was performed in Taenia taeniaeformis and Dipylidium caninum. Due to the presence of the eggs in their gravid segments, their histochemical and ultrastructural characteristics were also studied. It was found that the size, location and density of the calcareous bodies were different in different body parts of the same and the other cestode. Histochemically, the main component of these corpuscles was calcium; while other constituents as polysaccharides, lipids, protrins and mucopolysaccharides were found in their outer rim. Ultrastructurally, they were quite similar in the two studied cestodes and different stages of their development were exhibited. Histochemically, the eggs of both cestodes were similar in their contents. However, some ultrastructural differences have been demonstrated particularly in relation to the size and shape of the rods in the embryophore and the structures in between the embryophore and onchosphere.

Effects of a neem extract on blood feeding, oviposition and oocyte ultrastructure in Anopheles stephensi Liston (Diptera: Culicidae).

Science.gov (United States)

Lucantoni, L; Giusti, F; Cristofaro, M; Pasqualini, L; Esposito, F; Lupetti, P; Habluetzel, A

2006-12-01

Secondary metabolites of the neem tree (Azadirachta indica A. Juss., Meliaceae) exhibit a wide range of biological activities in insects. However, few studies have addressed the effects of neem extracts or compounds in arthropods of medical importance. In this study, a laboratory strain of Anopheles stephensi was used to assess the effects of a commercial formulation (Neem Azal) (NA)), containing azadirachtin A at 34%, on blood feeding, oviposition and oocyte ultrastructure. Oral administration of Neem Azal) to A. stephensi females through artificial blood meals did impair blood intake and oviposition in a concentration dependent manner. Similar results were obtained on females, which had consumed Neem Azal) in sucrose solution before taking a blood meal of plain blood. Neem treated females displayed a delay in oocyte development in both the phase of vitellogenesis and the phase of choriogenesis. The ultrastructural studies on ovaries from Neem Azal) treated females revealed distinct structural modifications indicative of: (i) a complete block of oogenesis, (ii) impairment of vitellogenesis and vitelline envelope formation, (iii) a severe degeneration of follicle cells. In agreement with results obtained in other insects, this study indicates that Neem Azal) impairs hormone control of oogenesis and exerts a cytotoxic effect on both follicular cells and oocytes of the Asian malaria vector A. stephensi.

First ultrastructural data on the human tapeworm Taenia asiatica eggs by scanning and transmission electron microscopy (SEM, TEM).

Science.gov (United States)

Galán-Puchades, M Teresa; Yang, Yichao; Marcilla, Antonio; Choe, Seongjun; Park, Hansol; Osuna, Antonio; Eom, Keeseon S

2016-09-01

Humans are definitive hosts of three species of the Taenia genus, namely Taenia solium, Taenia saginata and Taenia asiatica. The relative novelty of the latter explains the lack of knowledge concerning certain relevant aspects related to this parasite, such as its definite geographical distribution and whether its eggs can infect humans or not. So far, only the eggs of T. solium are known to be infective for humans, producing cysticercosis. Although eggs contain the infective stage, the oncosphere, there is a lack of research on the ultrastructure of eggs of human taeniids. We show, for the first time, the ultrastructure of eggs of T. asiatica by means of SEM and TEM analyses. We detected all the envelopes, namely the egg shell, vitelline layer, outer embryophoric membrane, embryophore, granular layer, basal membrane, oncospheral membrane and oncospheral tegument. Hooks surrounded by myofibrils and glycogen-like particles, the two types of secretory granules of the penetration glands, as well as several nuclei and mitochondria were also revealed in the oncospheres. In addition to the already known structures in eggs from other Taenia species, the presence of two types of small vesicles is described herein, possibly corresponding to exosomes and ectosomes because of their shape and size, which could participate in the host/parasite intercellular communication.

Spermatological characteristics of the genus Taenia inferred from the ultrastructural study on Taenia hydatigena.

Science.gov (United States)

Miquel, Jordi; Khallaayoune, Khalid; Azzouz-Maache, Samira; Pétavy, Anne-Françoise

2015-01-01

The present study attempts to establish the sperm ultrastructure baseline for Taenia hydatigena, which is essential for the future research on the location of specific proteins involved in spermatogenesis in this species. Thus, the ultrastructural organisation of the mature spermatozoon is described by means of transmission electron microscopy. Live tapeworms were obtained from an experimentally infected dog in the Department of Pathology and Public Health of the Agronomic and Veterinary Institute Hassan II of Rabat (Morocco). The spermatozoon of T. hydatigena is a filiform cell, which is tapered at both extremities and lacks mitochondria. It exhibits all the characteristics of type VII spermatozoon of tapeworms, namely a single axoneme, a crested body, spiralled cortical microtubules and nucleus, a periaxonemal sheath and intracytoplasmic walls. Other interesting characteristics are the presence of a 2000 nm long apical cone in its anterior extremity and only the axoneme in its posterior extremity. The ultrastructural characters of the spermatozoon of T. hydatigena are compared with those of other cestodes studied to date, with particular emphasis on representatives of the genus Taenia.

Effects of buprofezin on the ultrastructure of the third instar cuticle of the insect Trialeurodes vaporariorum.

Science.gov (United States)

De Cock, A; Degheele, D

1991-01-01

Treatment with buprofezin at the beginning of the third instar of Trialeurodes vaporariorum results in death of the larvae at the time of moulting. Electron microscopic observations, after treatment of the larvae with 20 mg a.i./l buprofezin, does not reveal any difference in the ultrastructural profile before apolysis, however formation of a normal lamellate procuticle is disturbed. The pharate procuticle is amorphous, varying in thickness and the mean thickness is greatly reduced. The subcuticle is interrupted several times at locations corresponding with the thinnest places of the pharate cuticle. Epidermal cells contain unusual structures such as myelin figures and hypertrophied mitochondria indicating that buprofezin may have an additional toxic effect on epidermal cells.

Ultrastructural changes during spermatogenesis, biochemical and hormonal evidences of testicular toxicity caused by TBT in freshwater prawn Macrobrachium rosenbergii (De Man, 1879).

Science.gov (United States)

Revathi, Peranandam; Iyapparaj, Palanisamy; Vasanthi, Lourduraj Arockia; Munuswamy, Natesan; Krishnan, Muthukalingan

2014-10-01

The present investigation documents the impact of tributyltin (TBT) on the ultrastructural variation of spermatogenesis in freshwater prawn Macrobrachium rosenbergii. The environmentally realistic concentration of TBT can cause damages to the endocrine and reproductive physiology of crustaceans. In this context, three concentrations viz. 10, 100, and 1000 ng/L were selected and exposed to prawns for 90 days. The TBT exposed prawn exhibited decrease the reproductive activity as evidenced by sperm count and sperm length compared to control. Histopathological results revealed the retarded testicular development, abnormal structure of seminiferous tubule, decrease in the concentration of spermatozoa, diminution of seminiferous tubule membrane, abundance of spermatocytes and vacuolation in testis of treated prawns. Ultrastructural study also confirmed the impairment of spermatogenesis in treated prawns. Furthermore, radioimmunoassay (RIA) clearly documented the reduction of testosterone level in TBT exposed groups. Thus, TBT substantially reduced the level of male sex hormone as well as biochemical constituents which ultimately led to impairment of spermatogenesis in the freshwater male prawn M. rosenbergii. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.

Ultrastructural changes of photodegradation of wood surfaces exposed to UV

International Nuclear Information System (INIS)

Kuo, M.L.; Hu, N.

1991-01-01

Red pine sapwood transverse and radial surfaces were exposed to ultraviolet (UV) light for 3 to 40 days. Effect of UV irradiation on ultrastructural changes of cell walls were studied by scanning (SEM) and transmission (TEM) electron microscopy. SEM study of transverse sections showed that during initial stages of UV irradiation, lignin in cell corners and in the compound middle lamellae was preferentially degraded and that the radial middle lamellae substained a greater rate of UV degradation than did the tangential middle lamellae. Massive cell wall degradation, as indicated by cell wall thinning, did not occur until surfaces were exposed to UV light for more than 10 days. TEM study of radial cell wall surfaces indicated that lignin lining the warty layer was removed by UV irradiation in 3 days and that warts were destroyed by a UV irradiation in 7 days. UV irradiation of cell wall surfaces produced a substantial amount of water-soluble degradation products. After 30 days of UV irradiation, the S3 layer was totally removed and revealed the very fragile S2 layer. (author)

Cypermethrin-induced histopathological, ultrastructural and biochemical changes in liver of albino rats: The protective role of propolis and curcumin

Directory of Open Access Journals (Sweden)

Manal Abdul-Hamid

2017-06-01

Full Text Available Cypermethrin (CYP, an insecticide belongs to a synthetic pyrethroid, is used for agriculture and household applications. The present study aimed to examine the toxic effects of CYP on rat liver and to clarify the hepatoprotective effects of propolis (PRO and curcumin (CUR against CYP. This study was assessed in male albino rats, each weighting (120–150 g. The rats were equally divided into six groups as follow; the 1st control group, 2nd PRO group (100 mg/kg/day and 3rd CUR group (100 mg/kg/day. While 4th, 5th and 6th groups were orally treated with CYP (30 mg/kg/day, CYP plus PRO and CYP plus CUR, respectively for 28 days. The present study revealed that CYP-induced significant increase in hepatic markers enzymes (ALT, AST and ALP and elevation in MDA concomitant with significant decrease of SOD and GPx levels. Histological and histochemical results revealed extensive vacuolar degeneration of hepatocytes, fatty change, blood vessel congestion and fibrosis in the liver of CYP- treated group and depletion of glycogen, protein and DNA. Moreover, ultrastructural observations showed vacuolation, damage of mitochondria and nuclear changes. On the other hand, treatment with PRO and CUR led to an obvious improvement of the injured liver tissues and ameliorating the damaging effects of CYP. In conclusion, PRO is markedly effective than CUR in protecting rats against CYP-induced histopathological, ultrastructural and biochemical changes. This protection may be due to its antioxidant properties and scavenging abilities against active free radicals.

Biological, Histological and Ultra-Structural Studies of Female Mullet ...

African Journals Online (AJOL)

Biological, Histological and Ultra-Structural Studies of Female Mullet, Mugil cephalus , Ovaries Collected from Different Habitats during Annual Reproductive Cycle. ... 35 and 52 cm, respectively; whereas, the total number of ripe ova in brackish water fish ranged from 0.57±0.14 to 3.81±0.59 x106 for the same length groups.

Giardia agilis: Ultrastructure of the Trophozoites in the Frog Intestine

Directory of Open Access Journals (Sweden)

Maria Inês L Sogayar

1998-05-01

Full Text Available Intestine samples of Bufo sp. tadpoles with parasitism confirmed for Giardia agilis were studied by transmission electron microscopy. The G. agilis trophozoites were long and thin. The plasma membrane was sometimes undulated and the cytoplasm, adjacent to the dorsal and ventral regions, showed numerous vacuoles. The two nuclei presented prominent nucleoli. The cytoplasm was electron-dense with free ribosomes, glycogen and rough endoplasmic reticulum-like structures. Polyhedral inclusions were observed in the cytoplasm and outside the protozoan; some of these inclusions exhibited membrane disruption. The flagella ultrastructure is typical, with the caudal pair accompanied by the funis. Next to the anterior pair, osmiophilic material was noticed. The ventro-lateral flange was short and thick, supported by the marginal plates that penetrated into its distal extremity; only its distal portion had adjacent osmiophilic filament. The G. agilis trophozoites showed the general subcellular feature of the genus. However, the ventro-lateral flange ultrastructure was an intermediate type between G. muris and G. duodenalis.

Ultrastructural investigation on radiation resistant microbial isolates of bacillus coagulans

International Nuclear Information System (INIS)

Tawfik, Z.S.

1992-01-01

Radiation resistant strains of bacillus coagulans were isolated from environmental atmospheric surrounding industrial cobalt-60 irradiator. D 1 0 value of the studied isolate was found to be 3.3 KGy. Ultrastructure studies were performed on control isolates as well as on isolates exposed to challenging doses of 12, 15 and 25 KGy. These dose values were delivered at two different dose rate values 40 Gy/min and 300 Gy/min. Ultrastructure studies showed small differences due to dose rate effect. These differences were not sufficient to cause lethality changes. It was demonstrated that the growing effect of dose value is concentrated on cellular material rather than on cellular membrane damages. The severeness of cell damage, due to received dose increase, was also demonstrated. Results suggest that repeated sub culturing may lead to repair of cell damage when it is subjected to sub sterilizing doses. This fact is of special interest when the sterilizing dose might be splitted in more than one fraction at different latent periods

MDL28170, a calpain inhibitor, affects Trypanosoma cruzi metacyclogenesis, ultrastructure and attachment to Rhodnius prolixus midgut.

Directory of Open Access Journals (Sweden)

Vítor Ennes-Vidal

Full Text Available BACKGROUND: Trypanosoma cruzi is the etiological agent of Chagas' disease. During the parasite life cycle, many molecules are involved in the differentiation process and infectivity. Peptidases are relevant for crucial steps of T. cruzi life cycle; as such, it is conceivable that they may participate in the metacyclogenesis and interaction with the invertebrate host. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we have investigated the effect of the calpain inhibitor MDL28170 on the attachment of T. cruzi epimastigotes to the luminal midgut surface of Rhodnius prolixus, as well as on the metacyclogenesis process and ultrastructure. MDL28170 treatment was capable of significantly reducing the number of bound epimastigotes to the luminal surface midgut of the insect. Once the cross-reactivity of the anti-Dm-calpain was assessed, it was possible to block calpain molecules by the antibody, leading to a significant reduction in the capacity of adhesion to the insect guts by T. cruzi. However, the antibodies were unable to interfere in metacyclogenesis, which was impaired by the calpain inhibitor presenting a significant reduction in the number of metacyclic trypomastigotes. The calpain inhibitor also promoted a direct effect against bloodstream trypomastigotes. Ultrastructural analysis of epimastigotes treated with the calpain inhibitor revealed disorganization in the reservosomes, Golgi and plasma membrane disruption. CONCLUSIONS/SIGNIFICANCE: The presence of calpain and calpain-like molecules in a wide range of organisms suggests that these proteins could be necessary for basic cellular functions. Herein, we demonstrated the effects of MDL28170 in crucial steps of the T. cruzi life cycle, such as attachment to the insect midgut and metacyclogenesis, as well as in parasite viability and morphology. Together with our previous findings, these results help to shed some light on the functions of T. cruzi calpains. Considering the potential roles of

Simultaneous ultrastructural analysis of fluorochrome-photoconverted diaminobenzidine and gold immunolabeling in cultured cells

Directory of Open Access Journals (Sweden)

M. Malatesta

2013-09-01

Full Text Available Diaminobenzidine photoconversion is a technique by which a fluorescent dye is transformed into a stably insoluble, brown, electrondense signal, thus enabling examination at both bright field light microscopy and transmission electron microscopy. In this work, a procedure is proposed for combining photoconversion and immunoelectron microscopy: in vitro cell cultures have been first submitted to photoconversion to analyse the intracellular fate of either fluorescent nanoparticles or photosensitizing molecules, then processed for transmission electron microscopy; different fixative solutions and embedding media have been used, and the ultrathin sections were finally submitted to post-embedding immunogold cytochemistry. Under all conditions the photoconversion reaction product and the target antigen were properly detected in the same section; Epon-embedded, osmicated samples required a pre-treatment with sodium metaperiodate to unmask the antigenic sites. This simple and reliable procedure exploits a single sample to simultaneously localise the photoconversion product and a variety of antigens allowing a specific identification of subcellular organelles at the ultrastructural level.

Spectral Analysis by XANES Reveals that GPNMB Influences the Chemical Composition of Intact Melanosomes

Energy Technology Data Exchange (ETDEWEB)

T Haraszti; C Trantow; A Hedberg-Buenz; M Grunze; M Anderson

2011-12-31

GPNMB is a unique melanosomal protein. Unlike many melanosomal proteins, GPNMB has not been associated with any forms of albinism, and it is unclear whether GPNMB has any direct influence on melanosomes. Here, melanosomes from congenic strains of C57BL/6J mice mutant for Gpnmb are compared to strain-matched controls using standard transmission electron microscopy and synchrotron-based X-ray absorption near-edge structure analysis (XANES). Whereas electron microscopy did not detect any ultrastructural changes in melanosomes lacking functional GPNMB, XANES uncovered multiple spectral phenotypes. These results directly demonstrate that GPNMB influences the chemical composition of melanosomes and more broadly illustrate the potential for using genetic approaches in combination with nano-imaging technologies to study organelle biology.

Effect of electrocautery on endothelial integrity of the internal thoracic artery: ultrastructural analysis with transmission electron microscopy.

Science.gov (United States)

Onan, Burak; Yeniterzi, Mehmet; Onan, Ismihan Selen; Ersoy, Burak; Gonca, Suheyla; Gelenli, Elif; Solakoglu, Seyhun; Bakir, Ihsan

2014-10-01

The internal thoracic artery (ITA) is typically harvested from the chest wall by means of conventional electrocautery. We investigated the effects of electrocautery on endothelial-cell and vessel-wall morphology at the ultrastructural level during ITA harvesting. Internal thoracic artery specimens from 20 patients who underwent elective coronary artery bypass grafting were investigated in 2 groups. The ITA grafts were sharply dissected with use of a scalpel and clips in the control group (n=10) and were harvested by means of electrocautery in the study group (n=10). Each sample was evaluated for intimal, elastic-tissue, muscular-layer, and adventitial changes. Free flow was measured intraoperatively. Light microscopic examinations were performed after hematoxylin-eosin and Masson's trichrome staining. Transmission electron microscopy was used to evaluate ultrastructural changes in the endothelial cells and vessel walls of each ITA. In the sharp-dissection group, the endothelial surfaces were lined with normal amounts of original endothelium, endothelial cells were distinctly attached to the basal lamina, cytoplasmic organelles were evident, and intercellular junctional complexes were intact. Conversely, in the electrocautery group, the morphologic integrity of endothelial cells was distorted, with some cell separations and splits, contracted cells, numerous large cytoplasmic vacuoles, and no visible cytoplasmic organelles. The subendothelial layer exhibited disintegration. Free ITA flow was higher in the sharp-dissection group (P=0.04). The integrity of endothelial cells can be better preserved when the ITA is mobilized by means of sharp dissection, rather than solely by electrocautery; we recommend a combined approach.

[Myocardial ultrastructural changes in rats following different levels of acute +Gz exposure].

Science.gov (United States)

Zheng, Jun; Liu, Cheng-gang; Ren, Li; Xiao, Xiao-guang; Xu, Shu-xuan; Wang, Ping; Ji, Gui-ying

2004-06-01

To observe the effects of different levels of acute +Gz exposure on myocardial ultrastructure of rats and provide experimental basis for further development of anti-G measures. Twenty male Wistar rats were randomly divided into 4 groups (n=5): normal control group, +20 Gz group, +10 Gz group and +5 Gz group. Profile of the centrifuge +Gz exposure was trapezoidal, in which +20 Gz lasted for 30 s, +10 Gz for 1.5 min. +5 Gz exposure was repeated for 3 times with 30 min interval and each for 1.5 min. Myocardial tissue of left ventricle was sampled for transmission electron microscopy 5 h after exposure. +20 Gz and +10 Gz exposure caused obvious edema of myocardial and endothelial cells, myofibril disorder and injuries of mitochondria and nucleus. Breaks of myocardial fiber, formation of contraction bands and rupture of mitochondria were also observed in +20 Gz group. In +5 Gz group, there was still slight edema of myocardial and endothelial cells, while organic changes of myocardial ultrastructure were not observed. High +Gz exposure can cause myocardial ultrastructural injury in rats. Slight reversible injured response can also be observed in myocardial cell after repeated moderate level of +Gz exposure. This indicates that attention should be paid to the study of the effect of high +Gz on heart in pilots.

Comparison of pigment cell ultrastructure and organisation in the dermis of marble trout and brown trout, and first description of erythrophore ultrastructure in salmonids.

Science.gov (United States)

Djurdjevič, Ida; Kreft, Mateja Erdani; Sušnik Bajec, Simona

2015-11-01

Skin pigmentation in animals is an important trait with many functions. The present study focused on two closely related salmonid species, marble trout (Salmo marmoratus) and brown trout (S. trutta), which display an uncommon labyrinthine (marble-like) and spot skin pattern, respectively. To determine the role of chromatophore type in the different formation of skin pigment patterns in the two species, the distribution and ultrastructure of chromatophores was examined with light microscopy and transmission electron microscopy. The presence of three types of chromatophores in trout skin was confirmed: melanophores; xanthophores; and iridophores. In addition, using correlative microscopy, erythrophore ultrastructure in salmonids was described for the first time. Two types of erythrophores are distinguished, both located exclusively in the skin of brown trout: type 1 in black spot skin sections similar to xanthophores; and type 2 with a unique ultrastructure, located only in red spot skin sections. Morphologically, the difference between the light and dark pigmentation of trout skin depends primarily on the position and density of melanophores, in the dark region covering other chromatophores, and in the light region with the iridophores and xanthophores usually exposed. With larger amounts of melanophores, absence of xanthophores and presence of erythrophores type 1 and type L iridophores in the black spot compared with the light regions and the presence of erythrophores type 2 in the red spot, a higher level of pigment cell organisation in the skin of brown trout compared with that of marble trout was demonstrated. Even though the skin regions with chromatophores were well defined, not all the chromatophores were in direct contact, either homophilically or heterophilically, with each other. In addition to short-range interactions, an important role of the cellular environment and long-range interactions between chromatophores in promoting adult pigment pattern

Adaptive response to starvation in the fish pathogen Flavobacterium columnare: cell viability and ultrastructural changes

Directory of Open Access Journals (Sweden)

Arias Covadonga R

2012-11-01

Full Text Available Abstract Background The ecology of columnaris disease, caused by Flavobacterium columnare, is poorly understood despite the economic losses that this disease inflicts on aquaculture farms worldwide. Currently, the natural reservoir for this pathogen is unknown but limited data have shown its ability to survive in water for extended periods of time. The objective of this study was to describe the ultrastructural changes that F. columnare cells undergo under starvation conditions. Four genetically distinct strains of this pathogen were monitored for 14 days in media without nutrients. Culturability and cell viability was assessed throughout the study. In addition, cell morphology and ultrastructure was analyzed using light microscopy, scanning electron microscopy, and transmission electron microscopy. Revival of starved cells under different nutrient conditions and the virulence potential of the starved cells were also investigated. Results Starvation induced unique and consistent morphological changes in all strains studied. Cells maintained their length and did not transition into a shortened, coccus shape as observed in many other Gram negative bacteria. Flavobacterium columnare cells modified their shape by morphing into coiled forms that comprised more than 80% of all the cells after 2 weeks of starvation. Coiled cells remained culturable as determined by using a dilution to extinction strategy. Statistically significant differences in cell viability were found between strains although all were able to survive in absence of nutrients for at least 14 days. In later stages of starvation, an extracellular matrix was observed covering the coiled cells. A difference in growth curves between fresh and starved cultures was evident when cultures were 3-months old but not when cultures were starved for only 1 month. Revival of starved cultures under different nutrients revealed that cells return back to their original elongated rod shape upon

Ultrastructural analysis of bone nodules formed in vitro by isolated fetal rat calvaria cells

International Nuclear Information System (INIS)

Bhargava, U.; Bar-Lev, M.; Bellows, C.G.; Aubin, J.E.

1988-01-01

When cells enzymatically digested from 21 d fetal rat calvaria are grown in ascorbic acid and Na beta-glycerophosphate, they form discrete three-dimensional nodular structures with the histological and immunohistochemical appearance of woven bone. The present investigation was undertaken to verify that bone-like features were identifiable at the ultrastructural level. The nodules formed on top of a fibroblast-like multilayer of cells. The upper surface of the nodules was lined by a continuous layer of cuboidal osteoblastic cells often seen to be joined by adherens junctions. Numerous microvilli, membrane protrusions, and coated pits could be seen on the upper surface of these cells, their cytoplasm contained prominent RER and Golgi membranes, and processes extended from their lower surfaces into a dense, highly organized collagenous matrix. Some osteocyte-like cells were completely embedded within this matrix; they also displayed RER and prominent processes which extended through the matrix and often made both adherens and gap junctional contacts with the processes of other cells. The fibroblastic cells not participating in nodule formation were surrounded by a less dense collagenous matrix and, in contrast to the matrix of the nodules, it did not mineralize. An unmineralized osteoid-like layer was seen directly below the cuboidal top layer of cells. A mineralization front was detectable below this in which small, discrete structures resembling matrix vesicles and feathery mineral crystals were evident and frequently associated with the collagen fibrils. More heavily mineralized areas were seen further into the nodule. Electron microprobe and electron and X-ray diffraction analysis confirmed the mineral to be hydroxyapatite

Ultrastructural analysis of oral exfoliated epithelial cells of tobacco smokers and betel nut chewers: A scanning electron microscopy study.

Science.gov (United States)

Khan, Sameera Shamim; Shreedhar, Balasundari; Kamboj, Mala

2016-01-01

The study was undertaken to correlate epithelial surface pattern changes of oral exfoliated cells of tobacco smokers and betel nut chewers and also to compare them with patients of oral squamous cell carcinoma (OSCC) and healthy individuals. In this cross-sectional study, a total of fifty persons were included in the study, out of which thirty formed the study group (15 each tobacco smokers and betel nut chewers) and twenty formed the control group (ten each of OSCC patients - positive control and ten normal buccal mucosa - negative control). Their oral exfoliated cells were scraped, fixed, and studied under scanning electron microscope (SEM). The statistical analysis was determined using ANOVA, Tukey honestly significant difference, Chi-square test, and statistical SPASS software, P betel nut chewers compared to normal oral mucosa have been tabulated. In normal oral mucosa, cell surface morphology depends on the state of keratinization of the tissue. Thus, it could prove helpful in detecting any carcinomatous change at its incipient stage and also give an insight into the ultra-structural details of cellular differentiations in epithelial tissues.

Radiation-induced changes in the ultrastructure and mechanical function of the rat heart

International Nuclear Information System (INIS)

Cilliers, G.D.; Lochner, A.

1989-01-01

A time sequence study was performed to study the early effects of radiation on the ultrastructure of the rat heart. Wistar rats were exposed to 20 Gy electron irradiation to a field including the heart and a third of the lung. The hearts were excised at varying time intervals (1 h-180 days), and the ultrastructure of perfusion-fixed subepicardium and subendocardium studied. Changes were observed in both myocytes and interstitium at all time intervals. The most pronounced change observed in the myocyte was that of intercalated disc damage which reached a peak at 30 days post-irradiation. Mitochondrial damage, characterized by swelling and fenstration in areas of myofibrillar contracture, was focal and relatively scarce. Swelling of the capillary endothelial cells and ollapse of the capillaries were marked up to 60 days. Of significance was the observation that the damage to both myocytes and interstitium receded after 60 days and the hearts exhibited an almost normal ultrastructure from 100 to 180 days post-irradiation. Mechanical function of these hearts followed a similar pattern: maximal depression was observed 60 days after irradiation. Thereafter the work performance of these hearts improved significantly, almost reaching control level after 180 days. (author). 34 refs.; 21 figs.; 1 tab

Type 1 diabetes mellitus effects on dental enamel formation revealed by microscopy and microanalysis.

Science.gov (United States)

Silva, Bruna Larissa Lago; Medeiros, Danila Lima; Soares, Ana Prates; Line, Sérgio Roberto Peres; Pinto, Maria das Graças Farias; Soares, Telma de Jesus; do Espírito Santo, Alexandre Ribeiro

2018-03-01

Type 1 diabetes mellitus (T1DM) largely affects children, occurring therefore at the same period of deciduous and permanent teeth development. The aim of this work was to investigate birefringence and morphology of the secretory stage enamel organic extracellular matrix (EOECM), and structural and mechanical features of mature enamel from T1DM rats. Adult Wistar rats were maintained alive for a period of 56 days after the induction of experimental T1DM with a single dose of streptozotocin (60 mg/kg). After proper euthanasia of the animals, fixed upper incisors were accurately processed, and secretory stage EOECM and mature enamel were analyzed by transmitted polarizing and bright field light microscopies (TPLM and BFLM), energy-dispersive x-ray (EDX) analysis, scanning electron microscopy (SEM), and microhardness testing. Bright field light microscopies and transmitted polarizing light microscopies showed slight morphological changes in the secretory stage EOECM from diabetic rats, which also did not exhibit statistically significant alterations in birefringence brightness when compared to control animals (P > .05). EDX analysis showed that T1DM induced statistically significant little increases in the amount of calcium and phosphorus in outer mature enamel (P  .05). T1DM also caused important ultrastructural alterations in mature enamel as revealed by SEM and induced a statistically significant reduction of about 13.67% in its microhardness at 80 μm from dentin-enamel junction (P enamel development, leading to alterations in mature enamel ultrastructure and in its mechanical features. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Ultrastructure of oogenesis in imposex females of Babylonia areolata (Caenogastropoda: Buccinidae)

Science.gov (United States)

Muenpo, C.; Suwanjarat, J.; Klepal, W.

2011-09-01

During a tributyltin (TBT)-exposure experiment, the ultrastructural features of oogenesis have been examined in TBT-induced imposex females of Babylonia areolata and compared with those of the normal female. The results obtained from such experiment demonstrates that B. areolata exhibits a low to moderate intensity of imposex because all VDSI values are never higher than 3. Ultrastructures of germ cell development including oogonia, pre-vitellogenic, early vitellogenic, late vitellogenic and mature oocytes show that oogenesis in imposex female is similar to that of normal females except for the presence of numerous lipid droplets in the cytoplasm of the oocytes and the follicle cells in imposex females, indicating the degeneration of their oocytes. Vitellogenesis in B. areolata involves both auto- and heterosynthetic processes that resemble those of the basal gastropods and the pulmonates. In addition, the presence of cortical granules and microvilli are unique structures of this species.

Effects of cadmium on ultrastructure and antioxidative defense system in hyperaccumulator and non-hyperaccumulator ecotypes of Sedum alfredii Hance

International Nuclear Information System (INIS)

Jin Xiaofen; Yang Xiaoe; Islam, Ejazul; Liu Dan; Mahmood, Qaisar

2008-01-01

Plant growth, ultrastructural and antioxidant adaptations and glutathione biosynthesis in Cd-hyperaccumulating ecotype Sedum alfredii Hance (HE) countering high Cd environment were investigated and compared with its non Cd-hyperaccumulating ecotype (NHE). Cadmium exposure resulted in significant ultrastructural changes in root meristem and leaf mesophyll cells of S. alfredii, but damage was more pronounced in NHE even when Cd concentrations were one-tenth of those applied to HE. Cadmium stress damaged chloroplasts causing imbalanced lamellae formation coupled with early leaf senescence. Histochemical results revealed that glutathione (GSH) biosynthesis inhibition led to overproduction of hydrogen peroxide (H 2 O 2 ) and superoxide radical (O 2 · - ) in HE but not in NHE. Differences were noted in both HE and NHE for catalase (CAT), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) and glutathione reductase (GR) activities under various Cd stress levels. No relationship was found between antioxidative defense capacity including activities of superoxide dismutase (SOD), CAT, GPX, APX and GR as well as ascorbic acid (AsA) contents and Cd tolerance in the two ecotypes of S. alfredii. The GSH biosynthesis induction in root and shoot exposed to elevated Cd conditions may be involved in Cd tolerance and hyperaccumulation in HE of S. alfredii H

Ultrastructural characterization of mesenchymal stromal cells labeled with ultrasmall superparamagnetic iron-oxide nanoparticles for clinical tracking studies

DEFF Research Database (Denmark)

Hansen, Louise; Hansen, Alastair B; Mathiasen, Anders B

2014-01-01

INTRODUCTION: To evaluate survival and engraftment of mesenchymal stromal cells (MSCs) in vivo, it is necessary to track implanted cells non-invasively with a method, which does not influence cellular ultrastructure and functional characteristics. Iron-oxide particles have been applied for cell...... sequence of trans-activator of transcription (TAT) (IODEX-TAT) and evaluate the effect of labeling on ultrastructure, viability, phenotype and proliferative capacity of the cells. MATERIALS AND METHODS: MSCs were labeled with 5 and 10 μg IODEX-TAT/10(5) cells for 2, 6 and 21 hours. IODEX-TAT uptake...... and cellular ultrastructure were determined by electron microscopy. Cell viability was determined by propidium iodide staining and cell proliferation capacity by 5-bromo-2-deoxyuridine (BrdU) incorporation. Maintenance of stem cell surface markers was determined by flow cytometry. Results. IODEX-TAT labeling...

[Peculiarities of ultrastructure of excretory system in Bothrioplana semperi (Platyhelminthes, Turbellaria)].

Science.gov (United States)

Kornakova, E E

2010-01-01

Ultrastructural study of morphology of cirtocytes and excretory channels was performed in the free living turbellaria Bothrioplana semperi (Turbellaria, Seriata). It has been shown that cirtocytes of this species are formed by two cells--the terminal and the proximal cells of the channel. The fan is composed of two rod rows. The external row goes out from the terminal cell, the internal one is a derivate of the channel proximal cell. Inside each rod of the external row there runs a bundle of microfilaments; it originates in the cytoplasm of the channel proximal cell distal to bases of the external rods. On the internal rod membranes there are noted small electrondense granules disposed separately or fused in the solid layer continuing into a dense "membrane" connecting rods of the external and internal rows. Rare internal leptotrichiae go out from the cirtocyte cavity bottom. External leptotrichiae are absent. The septate desmosome at the level of the terminal cell is absent, but is present in the channel proximal cell at the level of terminal of cilia. The apical surface of the channel cell carries rare short microvilli. The basement membrane of cells of excretory channels forms deep invaginations almost reaching the apical membrane. Epithelium of excretory channels is deprived of cilia. Ultrastructure of cirtocytes and excretory channels of B. semperi is similar to those in representatives of the suborder Proseriata (Seriata). The significance of ultrastructure of the Proseriata cirtocytes, especially of the order of formation of versh, for construction of phylogeny of Platyhelminthes is discussed.

Ultrastructure of canine meninges after repeated epidural injection of S(+)-ketamine.

Science.gov (United States)

Acosta, Alinne; Gomar, Carmen; Bombí, Josep A; Graça, Dominguita L; Garrido, Marta; Krauspenhar, Cristina

2006-01-01

The safety of ketamine when administered by the spinal route must be confirmed in various animal species before it is approved for use in humans. This study evaluates the ultrastructure of canine meninges after repeated doses of epidural S(+)-ketamine. Five dogs received S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days through an epidural catheter with its tip located at the L5 level. One dog received the same volume of normal saline at the same times. The spinal cord and meninges were processed for histopathological and ultrastructural studies. Clinical effects were assessed after each injection. Motor and sensory block appeared after each injection of S(+)-ketamine, but not in the dog receiving saline. No signs of clinical or neurologic alterations were observed. Using light microscopy, no meningeal layer showed alterations except focal infiltration at the catheter tip level by macrophages, lymphocytes, and a few mast cells. The cells of different layers were studied by electron microscopy and interpreted according to data from human and other animal species because no ultrastructural description of the canine meninges is currently available. There were no cellular signs of inflammation, phagocytosis, or degeneration in meningeal layers and no signs of atrophy, compression, or demyelinization in the areas of dorsal root ganglia and spinal cord around the arachnoid. These findings were common for dogs receiving S(+)-ketamine and the dog receiving saline. Repeated doses of epidural S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days was not associated to cellular alterations in canine meninges.

Ultrastructural changes in the isolated rat kidney induced by conjugated bilirubin and bile acids.

Science.gov (United States)

Gollan, J L; Billing, B H; Huang, S N

1976-10-01

The effects of bilirubin and bile acids on the ultrastructure of proximal renal tubules have been studied using an isolated rat kidney preparation, perfused with a protein-free dextran medium. Control kidneys perfused for 1 h had a normal glomerular filtration rate and effective renal plasma flow; the ultrastructure of proximal tubular cells was well preserved, with normal mitochondria, nuclear and plasma membranes, and microvilli of the brush border. When conjugated bilirubin, prepared from human hepatic bile, was added to the perfusion medium (5-0-7-5 mg/100 ml), marked alterations were observed in some cells, particularly with regard to the mitochondria and plasma membranes. These changes were greatly diminished by the inclusion of bovine albumin in the medium, indicating that the unbound fraction was primarily responsible for the tubular damage. The addition of taurocholate (450 muM), taurochenodeoxycholate (550 muM) or taurolithocholate (250 muM, bound to albumin) also produced plasma membrane changes, but only slight abnormalities were seen in the mitochondria and other structures. These ultrastructural observations support the concept that the elevated plasma levels of conjugated bilirubin and to a lesser extent bile acids are related to the renal failure associated with obstructive jaundice.

The ultrastructural surface morphology of oral cancer cells and keratinocytes after exposure to chitosan

Science.gov (United States)

Fatimah; Sarsito, A. S.; Wimardhani, Y. S.

2017-08-01

Low-molecular-weight chitosan (LMWC) has the same selective cytotoxic effects on oral cancer cells as cisplatin. The cell deaths caused by the anticancer characteristics of chitosan show that apoptosis is not the death pathway of the primary cells involved. The interactions between LMWC and the cells need to be explored. The objective of this study was to compare the ultrastructural morphology of oral Squamous Cell Carcinoma (SCC Ca)-922 and noncancer keratinocyte HaCaT cell lines after exposure to LMWC and cisplatin. The cells were treated with LMWC and cisplatin, and their ultrastructural morphology was analyzed using scanning electron micrographs. Features of early apoptosis, seen as the loss of microvilli, were detected in the LMWC-exposed Ca9-22 cells, and there was a material surrounding the cells. In contrast, the LMWC-exposed HaCaT cells showed no changes related to apoptosis. The results were the opposite when cisplatin was used. This study confirms that there are differences in the ultrastructural surface morphology of LMWC-exposed and cisplatin-exposed oral cancer cells and keratinocytes that could be correlated with their biological activity.

Morphological and ultrastructural evaluation of the golden retriever muscular dystrophy trachea, lungs, and diaphragm muscle.

Science.gov (United States)

Lessa, Thais Borges; de Abreu, Dilayla Kelly; Rodrigues, Márcio Nogueira; Brólio, Marina Pandolphi; Miglino, Maria Angélica; Ambrósio, Carlos Eduardo

2014-11-01

Duchenne muscular dystrophy (DMD) is a genetic disease, characterized by atrophy and muscle weakness. The respiratory failure is a common cause of early death in patients with DMD. Golden retriever muscular dystrophy (GRMD) is a canine model which has been extensively used for many advances in therapeutics applications. As the patients with DMD, the GRMD frequently died from cardiac and respiratory failure. Observing the respiratory failure in DMD is one of the major causes of mortality we aimed to describe the morphological and ultrastructural data of trachea, lungs (conductive and respiratory portion of the system), and diaphragm muscle using histological and ultrastructural analysis. The diaphragm muscle showed discontinuous fibers architecture, with different diameter; a robust perimysium inflammatory infiltrate and some muscle cells displayed central nuclei. GRMD trachea and lungs presented collagen fibers and in addition, the GRMD lungs showed higher of levels collagen fibers that could limit the alveolar ducts and alveoli distension. Therefore, the most features observed were the collagen areas and fibrosis. We suggested in this study that the collagen remodeling in the trachea, lungs, and diaphragm muscle may increase fibrosis and affect the trachea, lungs, and diaphragm muscle function that can be a major cause of respiratory failure that occur in patients with DMD. © 2014 Wiley Periodicals, Inc.

Investigation of the midgut structure and ultrastructure in Cimex lectularius and Cimex pipistrelli (Hemiptera: Cimicidae).

Science.gov (United States)

Rost-Roszkowska, M M; Vilimova, J; Włodarczyk, A; Sonakowska, L; Kamińska, K; Kaszuba, F; Marchewka, A; Sadílek, D

2017-02-01

Cimicidae are temporary ectoparasites, which means that they cannot obtain food continuously. Both Cimex species examined here, Cimex lectularius (Linnaeus 1758) and Cimex pipistrelli (Jenyns 1839), can feed on a non-natal host, C. lectularius from humans on bats, C. pipistrelli on humans, but never naturally. The midgut of C. lectularius and C. pipistrelli is composed of three distinct regions-the anterior midgut (AMG), which has a sack-like shape, the long tube-shaped middle midgut (MMG), and the posterior midgut (PMG). The different ultrastructures of the AMG, MMG, and PMG in both of the species examined suggest that these regions must fulfill different functions in the digestive system. Ultrastructural analysis showed that the AMG fulfills the role of storing food and synthesizing and secreting enzymes, while the MMG is the main organ for the synthesis of enzymes, secretion, and the storage of the reserve material. Additionally, both regions, the AMG and MMG, are involved in water absorption in the digestive system of both Cimex species. The PMG is the part of the midgut in which spherites accumulate. The results of our studies confirm the suggestion of former authors that the structure of the digestive tract of insects is not attributed solely to diet but to the basic adaptation of an ancestor.

Sporulation and ultrastructure in a late Proterozoic cyanophyte - Some implications for taxonomy and plant phylogeny

Science.gov (United States)

Cloud, P.; Moorman, M.; Pierce, D.

1975-01-01

Electron microscopical studies of a morphologically diverse, coccoid, presumably late Proterozoic blue-green alga are here reported. They show, together with light microscopy, that the form studied is widespread in the Cordilleran geosyncline, extend the record of well-defined endosporangia perhaps 700 million years into the past, and reveal previously unrecorded ultrastructural details. Coming from northeastern Utah, southwestern Alberta, and east central Alaska, these minute fossils belong to the recently described, morphologically diverse taxon Sphaerocongregus variabilis Moorman, are related to living entophysalidaceans, and have affinities with both the chroococcalean and chamaesiphonalean cyanophytes. Included in the morphological modes displayed by this alga are individual unicells, coenobial clusters of unicells, and a range of endosporangia comparable to those described for living entophysalidaceans. Scanning and transmission electron microscopy reveal that the endospores are commonly embedded in a vesicular matrix, that some of them show what appears to be a bilaminate or perhaps locally multilaminate wall structure, and that some remain together to mature as coenobial clones or 'colonies'. Taxonomic classification and phylogeny are discussed.

Ultrastructural damage of Loligo vulgaris and Illex coindetii statocysts after low frequency sound exposure.

Directory of Open Access Journals (Sweden)

Marta Solé

Full Text Available There is a considerable lack of information concerning marine invertebrate sensitivity to sound exposure. However, recent findings on cuttlefish and octopi showed that exposure to artificial noise had a direct consequence on the functionality and physiology of the statocysts, sensory organs, which are responsible for their equilibrium and movements in the water column. Owing to a lack of available data on deep diving cephalopod species, we conducted a noise exposure comparative experiment on one Mediterranean squid, Illex coindetii, and on the European squid Loligo vulgaris. Scanning electron microscopy (SEM revealed similar injuries in the inner structure of the statocysts, as those found in cuttlefish and octopi. In addition to the ultrastructural description of the lesions, we publish here the first images of the crista-cupula system and inner statocyst cavity of I. coindetii.

Surface topography and ultrastructural changes of mucinous carcinoma breast cells.

Science.gov (United States)

Voloudakis, G E; Baltatzis, G E; Agnantis, N J; Arnogianaki, N; Misitzis, J; Voloudakis-Baltatzis, I

2007-01-01

Mucinous carcinoma of the breast (MCB) is histologically classified into 2 groups: (1) pure MCB and (2) mixed MCB. Pure MCB carries a better diagnosis than mixed MCB. This research relates to the cell surface topography and ultrastructure of the cells in the above cases and aims to find the differences between them, by means of two methods: scanning electron microscopy (SEM) and transmission electron microscopy (TEM). For the SEM examination, it was necessary to initially culture the MCB tissues and then proceed with the usual SEM method. In contrast, for the TEM technique, MCB tissues were initially fixed followed by the classic TEM method. The authors found the topography of pure MCB cases to be without nodes. The cell membrane was smooth, with numerous pores and small ruffles that covered the entire cell. The ultrastructural appearance of the same cases was with a normal cell membrane containing abundant collagen fibers. They also had many small vesicles containing mucin as well as secretory droplets. In contrast the mixed MCB had a number of lymph nodes and their cell surface topography showed stronger changes such as microvilli, numerous blebs, ruffles and many long projections. Their ultrastructure showed very long microvilli with large cytoplasmic inclusions and extracellular mucin collections, electron-dense material vacuoles, and many important cytoplasmic organelles. An important fact is that mixed MCB also contains areas of infiltrating ductal carcinoma. These cells of the cytoplasmic organelles are clearly responsible for the synthesis, storage, and secretion of the characteristic mucin of this tumor type. Evidently, this abnormal mucin production and the abundance of secretory granules along with the long projections observed in the topographical structure might be responsible for transferring tumor cells to neighboring organs, thus being responsible for metastatic disease.

Histopathological, Ultrastructural and Apoptotic Changes in Diabetic Rat Placenta

Directory of Open Access Journals (Sweden)

Mehmet Gül

2015-09-01

Full Text Available Background: The exchange of substances between mother and fetus via the placenta plays a vital role during development. A number of developmental disorders in the fetus and placenta are observed during diabetic pregnancies. Diabetes, together with placental apoptosis, can lead to developmental and functional disorders. Aims: Histological, ultrastructural and apoptotic changes were investigated in the placenta of streptozotocin (STZ induced diabetic rats. Study Design: Animal experimentation. Methods: In this study, a total of 12 female Wistar Albino rats (control (n=6 and diabetic (n=6 were used. Rats in the diabetic group, following the administration of a single dose of STZ, showed blood glucose levels higher than 200 mg/dL after 72 hours. When pregnancy was detected after the rats were bred, two pieces of placenta and the fetuses were collected on the 20th day of pregnancy by cesarean incision under ketamine/xylazine anesthesia from in four rats from the control and diabetic groups. Placenta tissues were processed for light microscopy and transmission electron microscopy (TEM. Hematoxylin-eosin (HE and periodic acid Schiff-diastase (PAS-D staining for light microscopic and caspase-3 staining for immunohistochemical investigations were performed for each placenta. Electron microscopy was performed on thin sections contrasted with uranyl acetate and lead nitrate. Results: Weight gain in the placenta and fetuses of diabetic rats and thinning of the decidual layer, thickening of the hemal membrane, apoptotic bodies, congestion in intervillous spaces, increased PAS-D staining in decidual cells and caspase-3 immunoreactivity were observed in the diabetic group. After the ultrastructural examination, the apoptotic appearance of the nuclei of trophoblastic cells, edema and intracytoplasmic vacuolization, glycogen accumulation, dilation of the endoplasmic reticulum and myelin figures were observed. In addition, capillary basement membrane thickening

Ultrastructural study of the chromatoid body in planarian regenerative cells

Energy Technology Data Exchange (ETDEWEB)

Hori, I. (Kanazawa Medical Univ., Ishikawa (Japan))

1982-04-01

The present paper deals with the ultrastructural changes of chromatoid bodies in planarian regenerative cells under normal and experimental conditions. A close relationship was usually observed between chromatoid bodies and pore regions of the nuclear envelope in these cells. The chromatoid bodies continued to decrease in size during cytodifferentiation of regenerative cells, though they did not disappear entirely throughout the regeneration processes. Cytochemistry and (/sup 3/H)uridine autoradiography have shown that the chromatoid body contains RNA. The typical morphological effect of actinomycin D became apparent in three organelles, i.e., nucleolus, polysome and chromatoid body. Ultrastructural changes in nucleoli were observed to occur after actinomycin treatment (20 ..mu..g/ml). The exposure to a higher dose of actinomycin (50 ..mu..g/ml) caused a decay of chromatoid bodies while nuclear envelopes retained numerous pores. Both the nucleoli and the chromatoid bodies disappeared in the sequential stages. Within the cytoplasm of such cells disintegration of a polysomal pattern was correlated with the disappearance of chromatoid bodies. The significance of the planarian chromatoid body is discussed in relation to differentiation of the regenerative cells.

Ultrastructural observations of chemical peeling for skin rejuvenation (ultrastructural changes of the skin due to chemical peeling).

Science.gov (United States)

Omi, Tokuya; Sato, Shigeru; Numano, Kayoko; Kawana, Seiji

2010-02-01

Chemical peeling of the skin is commonly used as a means to treat photoaging, but the mechanism underlying its efficacy has not yet been fully clarified. We recently conducted chemical peeling of the skin with glycolic acid and lactic acid and observed it at the ultrastructural level. No changes in the horny layer or the upper epidermal layer were observed but there was dissociation and vacuolation between the basal cells and increases in vimentin filaments within fibroblasts and endothelial cells were seen. These findings suggest that chemical peeling of the skin with this type of agent directly induces collagen formation within the dermis and thus directly stimulates remodeling of the dermis.

Changes in ultrastructure of rat ovaries after early postnatal x-ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, A [Juntendo Univ., Tokyo (Japan). School of Medicine

1975-02-01

Female rats were irradiated with 190R of X-rays at 10 days of age and the ovarian ultrastructures were studied 4 and 7 months after irradiation. Ultrastructural changes were found in germinal epithelial cells, in fibroblasts in the tunica albuginea and in interstitial cells. The germinal epithelial cells exhibited various signs of degeneration but no sign of proliferation. Electron density of their basal part was reduced considerably. Their mitochondria became swollen and free ribosomes were decreased in number. The nuclei often protruded from the free surface of these cells. These cells frequently fragmented and, finally, complete desquamation occurred. The basement membrane became unevently thickened. Nuclei of enlarged fibroblasts in the tunica albuginea became irregularly ellipsoid in shape, and the nuclear envelope was occasionally invaginated. Various cytoplasmic organelles of the fibroblasts were well-developed. Some abnormal invasion of cytoplasm into the nucleus was found in the interstitial cells showing the ultrastructural characteristics of steroid hormone synthesis. Various cytoplasmic roganelles and inclusions invaded into the nuclei of these cells and the nuclear envelope sometimes disappeared locally. These interstitial cells contained a large number of irregular-shaped electron dense mitochondria with vesicular cristae, and numerous dilated vesicles of smooth-surfaced endoplasmic reticulum (SER). The cells of the anovular follicles in the irradiated ovaries resembled, in fine structure, the granulosa cells in normal primary follicles of non-irradiated ovaries. These cells seemed to be less affected by early postnatal irradiation.

Ultra-structural study of Egyptian Buffalo oocytes before and after in ...

African Journals Online (AJOL)

The oocytes examined in this study showed normal ultra-structure of mitochondria, smooth endoplasmic reticulum (SER), zona pellucida (ZP), lipid droplets, vesicles and Golgi in the good type meanwhile, some differences and abnormalities in denuded oocytes were recorded. The most remarkable changes observed in the ...

Biochemical and ultrastructural changes in the liver of European perch (Perca fluviatilis L. in response to cyanobacterial bloom in the Gruža reservoir

Directory of Open Access Journals (Sweden)

Perendija Branka R.

2011-01-01

Full Text Available We investigated the biochemical and ultrastructural changes in the liver of the freshwater fish, European perch (Perca fluviatilis, in response to Aphanizomenon flos-aquae bloom in the Gruža Reservoir, Serbia. The activities of total manganese- and copper zinc-containing superoxide dismutase (Tot SOD, Mn-SOD, Cu/Zn-SOD, catalase (CAT, glutathione peroxidase (GSH-Px, glutathione reductase (GR and biotransformation phase II enzyme glutathione-S-transferase (GST, as well as concentrations of total glutathione (GSH and sulfhydryl (-SH groups were examined before and during the bloom period. Mn-SOD activity was significantly higher, while the activities of Cu/Zn-SOD, CAT and GSH-Px and the concentration of the -SH groups were significantly lower during the bloom. The ultrastructure of the liver revealed necrotic and apoptotic damage to the hepatocytes during the bloom period. Our work represents the first study to report the influences of an Aphanizomenon flos-aquae bloom in the Gruža Reservoir on antioxidant biomarkers and on histopathological alterations in the liver of the freshwater fish European perch (Perca fluviatilis.

Community Composition and Ultrastructure of a Nitrate-Dependent Anaerobic Methane-Oxidizing Enrichment Culture.

Science.gov (United States)

Gambelli, Lavinia; Guerrero-Cruz, Simon; Mesman, Rob J; Cremers, Geert; Jetten, Mike S M; Op den Camp, Huub J M; Kartal, Boran; Lueke, Claudia; van Niftrik, Laura

2018-02-01

Methane is a very potent greenhouse gas and can be oxidized aerobically or anaerobically through microbe-mediated processes, thus decreasing methane emissions in the atmosphere. Using a complementary array of methods, including phylogenetic analysis, physiological experiments, and light and electron microscopy techniques (including electron tomography), we investigated the community composition and ultrastructure of a continuous bioreactor enrichment culture, in which anaerobic oxidation of methane (AOM) was coupled to nitrate reduction. A membrane bioreactor was seeded with AOM biomass and continuously fed with excess methane. After 150 days, the bioreactor reached a daily consumption of 10 mmol nitrate · liter -1 · day -1 The biomass consisted of aggregates that were dominated by nitrate-dependent anaerobic methane-oxidizing " Candidatus Methanoperedens"-like archaea (40%) and nitrite-dependent anaerobic methane-oxidizing " Candidatus Methylomirabilis"-like bacteria (50%). The " Ca Methanoperedens" spp. were identified by fluorescence in situ hybridization and immunogold localization of the methyl-coenzyme M reductase (Mcr) enzyme, which was located in the cytoplasm. The " Ca Methanoperedens" sp. aggregates consisted of slightly irregular coccoid cells (∼1.5-μm diameter) which produced extruding tubular structures and putative cell-to-cell contacts among each other. " Ca Methylomirabilis" sp. bacteria exhibited the polygonal cell shape typical of this genus. In AOM archaea and bacteria, cytochrome c proteins were localized in the cytoplasm and periplasm, respectively, by cytochrome staining. Our results indicate that AOM bacteria and archaea might work closely together in the process of anaerobic methane oxidation, as the bacteria depend on the archaea for nitrite. Future studies will be aimed at elucidating the function of the cell-to-cell interactions in nitrate-dependent AOM. IMPORTANCE Microorganisms performing nitrate- and nitrite-dependent anaerobic

Ultrastructural study of Rift Valley fever virus in the mouse model

Energy Technology Data Exchange (ETDEWEB)

Reed, Christopher; Steele, Keith E.; Honko, Anna; Shamblin, Joshua; Hensley, Lisa E. [United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, MD (United States); Smith, Darci R., E-mail: darci.smith1@us.army.mil [United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, MD (United States)

2012-09-15

Detailed ultrastructural studies of Rift Valley fever virus (RVFV) in the mouse model are needed to develop and characterize a small animal model of RVF for the evaluation of potential vaccines and therapeutics. In this study, the ultrastructural features of RVFV infection in the mouse model were analyzed. The main changes in the liver included the presence of viral particles in hepatocytes and hepatic stem cells accompanied by hepatocyte apoptosis. However, viral particles were observed rarely in the liver; in contrast, particles were extremely abundant in the CNS. Despite extensive lymphocytolysis, direct evidence of viral replication was not observed in the lymphoid tissue. These results correlate with the acute-onset hepatitis and delayed-onset encephalitis that are dominant features of severe human RVF, but suggest that host immune-mediated mechanisms contribute significantly to pathology. The results of this study expand our knowledge of RVFV-host interactions and further characterize the mouse model of RVF.

Ultrastructural study of Rift Valley fever virus in the mouse model

International Nuclear Information System (INIS)

Reed, Christopher; Steele, Keith E.; Honko, Anna; Shamblin, Joshua; Hensley, Lisa E.; Smith, Darci R.

2012-01-01

Detailed ultrastructural studies of Rift Valley fever virus (RVFV) in the mouse model are needed to develop and characterize a small animal model of RVF for the evaluation of potential vaccines and therapeutics. In this study, the ultrastructural features of RVFV infection in the mouse model were analyzed. The main changes in the liver included the presence of viral particles in hepatocytes and hepatic stem cells accompanied by hepatocyte apoptosis. However, viral particles were observed rarely in the liver; in contrast, particles were extremely abundant in the CNS. Despite extensive lymphocytolysis, direct evidence of viral replication was not observed in the lymphoid tissue. These results correlate with the acute-onset hepatitis and delayed-onset encephalitis that are dominant features of severe human RVF, but suggest that host immune-mediated mechanisms contribute significantly to pathology. The results of this study expand our knowledge of RVFV–host interactions and further characterize the mouse model of RVF.

Ultrastructural Characterization of Zika Virus Replication Factories

Directory of Open Access Journals (Sweden)

Mirko Cortese

2017-02-01

Full Text Available Summary: A global concern has emerged with the pandemic spread of Zika virus (ZIKV infections that can cause severe neurological symptoms in adults and newborns. ZIKV is a positive-strand RNA virus replicating in virus-induced membranous replication factories (RFs. Here we used various imaging techniques to investigate the ultrastructural details of ZIKV RFs and their relationship with host cell organelles. Analyses of human hepatic cells and neural progenitor cells infected with ZIKV revealed endoplasmic reticulum (ER membrane invaginations containing pore-like openings toward the cytosol, reminiscent to RFs in Dengue virus-infected cells. Both the MR766 African strain and the H/PF/2013 Asian strain, the latter linked to neurological diseases, induce RFs of similar architecture. Importantly, ZIKV infection causes a drastic reorganization of microtubules and intermediate filaments forming cage-like structures surrounding the viral RF. Consistently, ZIKV replication is suppressed by cytoskeleton-targeting drugs. Thus, ZIKV RFs are tightly linked to rearrangements of the host cell cytoskeleton. : Cortese et al. show that ZIKV infection in both human hepatoma and neuronal progenitor cells induces drastic structural modification of the cellular architecture. Microtubules and intermediate filaments surround the viral replication factory composed of vesicles corresponding to ER membrane invagination toward the ER lumen. Importantly, alteration of microtubule flexibility impairs ZIKV replication. Keywords: Zika virus, flavivirus, human neural progenitor cells, replication factories, replication organelles, microtubules, intermediate filaments, electron microscopy, electron tomography, live-cell imaging

Polarized Ends of Human Macula Densa Cells: Ultrastructural Investigation and Morphofunctional Correlations.

Science.gov (United States)

Cangiotti, Angela Maria; Lorenzi, Teresa; Zingaretti, Maria Cristina; Fabri, Mara; Morroni, Manrico

2018-05-01

The morphology of the kidney macula densa (MD) has extensively been investigated in animals, whereas human studies are scanty. We studied the fine structure of human MD cells focusing on their apical and basal ends and correlating structure and function. The MD region was examined by transmission electron microscopy in six renal biopsies from patients with kidney disease. Ultrastructural analysis of MD cells was performed on serial sections. MD cells show two polarized ends. The apical portion is characterized by a single, immotile cilium associated with microvilli; apically, cells are joined by adhering junctions. In the basal portion, the cytoplasm contains small, dense granules and numerous, irregular cytoplasmic projections extending to the adjacent extraglomerular mesangium. The projections often contain small, dense granules. A reticulated basement membrane around MD cells separates them from the extraglomerular mesangium. Although the fact that tissue specimens came from patients with kidney disease mandates extreme caution, ultrastructural examination confirmed that MD cells have sensory features due to the presence of the primary cilium, that they are connected by apical adhering junctions forming a barrier that separates the tubular flow from the interstitium, and that they present numerous basal interdigitations surrounded by a reticulated basement membrane. Conceivably, the latter two features are related to the functional activity of the MD. The small, dense granules in the basal cytoplasm and in cytoplasmic projections are likely related to the paracrine function of MD cells. Anat Rec, 301:922-931, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Scanning electron microscopy of dentition: methodology and ultrastructural morphology of tooth wear.

Science.gov (United States)

Shkurkin, G V; Almquist, A J; Pfeihofer, A A; Stoddard, E L

1975-01-01

Scanning electron micrographs were taken of sets of human molars-those of paleo-Indians used in mastication of, ostensibly, a highly abrasive diet, and those of contemporary Americans. Different ultrastructural patterns of enamel wear were observed between the groups.

Ultrastructure of the body wall of female Philometra obturans (Nematoda: Dracunculoidea)

Czech Academy of Sciences Publication Activity Database

Frantová, Denisa; Bruňanská, Magdaléna; Fagerholm, H.-P.; Kihlström, M.

2005-01-01

Roč. 95, č. 5 (2005), s. 327-332 ISSN 0932-0113 R&D Projects: GA ČR(CZ) GA524/03/0061 Institutional research plan: CEZ:AV0Z60220518 Keywords : Nematoda * ultrastructure * cuticule Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.226, year: 2005

Ultrastructural analysis of Apicomplexa-Like parasites in two conch species Laevistrombus canarium and canarium urceus from Johor Straits, Malaysia.

Science.gov (United States)

Azmi, Nur-Fauzana; Ghaffar, Mazlan Abd; Daud, Hassan Hj Mohd; Cob, Zaidi Che

2018-02-01

The tropical conch, Laevistrombus canarium (Linnaeus, 1758) and Canarium urceus (Linneaus, 1758) are ecologically and economically important shellfish species in Malaysia and neighboring region. Their populations, however are currently declining and this histopathological study investigates the aspect of parasitism and diseases that may affect their well-being. Conch samples were randomly collected from their natural habitat and histological sections (4-5 µm) of various organs and tissues were examined under light microscope. This was followed by ultrastructure analysis on infected tissues using transmission electron microscope (TEM). Based on the histological analysis, large numbers of gamonts, sporocysts and trophozoites of Apicomplexa-like parasites were observed in the vacuolated cells and pyramidal crypt cells of the digestive tubules, and in the digestive ducts. Furthermore, coccidian and oocysts-like Pseudoklossia sp. stages were also observed in the cells of the kidney. Apart from that, spores with cyst-like structure were observed in the digestive gland and kidney. Although the parasites were present in most of the organs analyzed, there was no obvious symptom, inflammatory response or mortality incurred on both species, which implies the possibility of a non-virulent relationship like commensalisms or mutualism. However, more investigations, including molecular studies, are needed to confirm the parasite identification and dynamics, and to further evaluate the nature of relationship between Apicomplexa parasites and their host. Copyright © 2018 Elsevier Inc. All rights reserved.

Ultrastructural Changes in Cherimoya Fruit Injured by Chilling

OpenAIRE

Gutierrez, Margarita; Mar Sola, Maria del; Pascual, Luis; Rodriguez-Garcia, Maria Isabel; Vargas, Alberto M.

1992-01-01

Cherimoya (Annona cherimola Mill.) is an important fruit crop that is grown in the South of Spain. Ultrastructural modifications of cherimoya fruit were studied after low-temperature storage. When cherimoya was stored at 4 oc for 6 days, the starch grains did not suffer degradation and the cell walls remained intact. The membrane systems were severely damaged , result ing in a loss of cell compartmentalization. Cherimoya rewarmed to 22 0 C after 9 days of low temperature storage is not able t...

[Spermatogonia types in tepezcuintle (Cuniculus paca). Ultrastructural study].

Science.gov (United States)

Ureña, F; Bolaños, R; Rojas, N; Suárez, R; Quesada, R

1988-11-01

Ultrastructural studies of different types of spermatogonia by thin section techniques and transmission electron microscopy showed that Cuniculus paca has two types of Type A spermatogonia (A-O and A-1). Samples were taken at different stages of the cycle in the seminiferous tubule epithelium presented a similar pattern as those of other rodents. Type B spermatogonia are similar to those of the rat, the difference being that the heterochromatic zones are larger and more numerous. Both characteristics differentiate them from preleptotenic spermatocytes.

Ultrastructural analysis of kidney, liver and duodenum isolated from treated rats with Ginkgo Biloba extract and effects of this medicinal plant on the biodistribution of the padiopharmaceutical sodium pertechnetate

Directory of Open Access Journals (Sweden)

Silvana Ramos Farias Moreno

2008-12-01

Full Text Available Ginkgo biloba extract (EGb has been used to treat memory and concentration deficits, acts as platelet activating factor antagonism and prevents against damages caused by free radicals. EGb is a standardized extract that contains 24% flavonoids and 6% terpenoids. The aim of this work was to evaluate the possible influence of an EGb on the ultrastructure of some organs isolated from rats and on the biodistribution of sodium pertechnetate (99mTcO4Na. The animals were treated with EGb and after six days, received 99mTcO4Na. The organs were isolated and fixed for ultrastructural analysis. The results showed that EGb has modified the ultrastructure of kidney, liver and duodenum and altered the biodistribution of 99mTcO4Na (PO extrato de Ginkgo Biloba extract (EGb tem sido usado para tratar dificuldades de concentração, memória, age como antagonista do fator de ativação de plaquetas e previne contra danos causados por radicais livres. EGb é um extrato padronizado com 24% de flavonóides e 6% de lactonas terpênicas. O objetivo deste estudo foi avaliar o efeito de um EGb na ultraestrutura de alguns órgãos isolados de ratos e na biodistribuição do radiofármaco pertecnetato de sódio (99mTcO4Na. Os animais foram tratados com EGb e após 6 dias receberam 99mTcO4Na. Os órgãos foram isolados e a radioatividade determinada. Os tecidos foram fixados para microscopia eletrônica. Os resultados mostraram que EGb alterou a ultraestrutura do rim, figado e duodeno e modificou a biodistribuição do 99mTcO4Na. Sugerimos que substâncias presentes no EGb poderiam agir diretamente ou gerar metabólitos capazes de promover alterações na biodistribuição e na morfologia de órgãos em nível ultraestrutural.

Ultrastructure of the human preovulatory oocyte.

Science.gov (United States)

Szöllösi, D; Mandelbaum, J; Plachot, M; Salat-Baroux, J; Cohen, J

1986-08-01

The ultrastructure of preovulatory human oocyte-cumulus complexes was described after inducing maturation by clomiphene, human menopausal gonadotropin (hMG), human chorionic gonadotropin (hCG) treatment. The majority of the oocytes was at metaphase II of meiosis, with a radially orientated spindle. The oocyte surface was covered by a multitude of microvilli. Cortical granules were nonuniformly distributed along the cortex. A cytoplasmic polarization was observed. The cytoplasmic organelles were in general uniformly dispersed, with the exception of a narrow segment within which cytoplasmic membranes and mitochondria formed clusters. The spindle was usually found at the borderline between the two regions of the cytoplasm. The functional significance of this polarization is not yet known.

Ultrastructure and electrophoretic protein pattern of a nuclear fraction enriched in interchromatin granule conglomerations

Energy Technology Data Exchange (ETDEWEB)

Krzyzowska-Gruca, S.; Zborek, A.; Gruca, S.

1986-01-01

Rats were injected with a cytostatic 1-nitro-9/3'-dimethylpropyloamine/acridine.2HCl to induce aggregation of interchromatin granules (IG). The conglomerations of IG were well preserved in isolated liver nuclei and in nuclear structures deprived of chromatin. This feature enabled obtaining a nuclear fraction enriched in IG. The method consisted in extraction of isolated nuclei with a non-ionic detergent and digestion with DNase I in a high ionic strength. Each step of isolation was ultrastructurally monitored using both the routine electron microscopy as well as a preferential staining of IG with bismuth. Presence of spots of tightly packed granules within IG conglomerations in the final fraction like in the nuclei in situ was a good ultrastructural marker of IG. The resulting fraction consisted predominantly of IG conglomerations. Their preferential staining with bismuth was well preserved. Minute amounts of fibrillar material originating from nuclear matrix and residual nuclei could be observed. Protein composition of the fraction enriched in IG was studied by SDS-polyacrylamide gel electrophoresis. After electrotransfer, nitrocellulose filters were fixed with glutaraldehyde and stained with bismuth method in order to identify IG proteins. The results of ultrastructural and cytochemical studies in comparison to electrophoretic protein pattern are discussed.

Effect of extract of Hibiscus on the ultrastructure of the testis in adult mice.

Science.gov (United States)

Mahmoud, Yomna Ibrahim

2012-07-01

Hibiscus sabdariffa extract is a popular beverage in many tropical and sub-tropical countries. Although, Hibiscus tea is known for its medicinal effects for thousands of years, scientific evidence of its systemic safety is very limited. The current study aimed to assess the potential adverse effects of H. sabdariffa extract on sperm morphology and testicular ultrastructure of albino mice. Thirty adult male albino mice were divided into three equal groups and were given: (a) distilled water, (b) cold Hibiscus aqueous extract, and (c) boiled Hibiscus aqueous extract. Hibiscus extract was administered orally daily for 4 weeks in a dose of 200 mg/kg body weight/mouse. Twenty-four hours after the last treatment, mice were decapitated and the testes and epididymides were excised and processed for transmission electron microscopy to assess ultrastructural and sperm abnormalities. The results clearly demonstrate that aqueous extracts from dried calyx of H. sabdariffa, either cold or boiled, alter normal sperm morphology and testicular ultrastructure and adversely influence the male reproductive fertility in albino mice. The current data suggest that Hibiscus extract should be consumed with caution, and reasonable estimates of the human risk associated with its consumption should be provided. Copyright © 2011 Elsevier GmbH. All rights reserved.

Study on ultrastructural changes in thyroid gland of rats exposed to pulsed electromagnetic wave

International Nuclear Information System (INIS)

Zhou Xiaoguang; Zeng Guiying; Ren Dongqing; Fang Henghu; Su Xiaoming; Huang Xiaofeng

2006-01-01

The work is to observe effects of PEMW (pulse electromagnetic wave) exposure on function and morphology of thyroid gland of rats. At different time points (24, 48, 96 and 192 h) after exposure to PEMW (E=115 kV m -1 , 12000 pulses), radioimmunoassay was performed to observe the levels of thyroid-stimulating hormone (TSH), thyroxine (T 4 ) and triiodo- thyronine (T 3 ) in sera of the male Sparague-Dawley rats. Optic microscopy and transmission electron microscopy (TEM) were used to observe structural changes of the thyroid gland at the time points. The T 3 , T 4 and TSH in sera increased significantly, reaching a peak at 24 h and decreasing gradually then. Although no obvious changes in the thyroid gland were observed under the optic microscope, some ultrastructural changes in the thyroid gland were found under the TEM. The ultrastructures were obviously changed at 12 h and aggravated until 48 h. In the experimented rats, dilatated endoplasmic reticulum gathered with lots of protein excretion, lipid droplet and heterochromatin gathered under the nucleus membranes were observed in follicular epithelial cells. These changes were palliated at 96 h but not recovered. PEMW can affect levels of hormones in sera and the hazard ultrastructural changes of thyroid gland. Endoplasmic reticulum is the main injured organelle. (authors)

Reorganization of the Endosomal System in Salmonella-Infected Cells: The Ultrastructure of Salmonella-Induced Tubular Compartments

Science.gov (United States)

Krieger, Viktoria; Liebl, David; Zhang, Yuying; Rajashekar, Roopa; Chlanda, Petr; Giesker, Katrin; Chikkaballi, Deepak; Hensel, Michael

2014-01-01

During the intracellular life of Salmonella enterica, a unique membrane-bound compartment termed Salmonella-containing vacuole, or SCV, is formed. By means of translocated effector proteins, intracellular Salmonella also induce the formation of extensive, highly dynamic membrane tubules termed Salmonella-induced filaments or SIF. Here we report the first detailed ultrastructural analyses of the SCV and SIF by electron microscopy (EM), EM tomography and live cell correlative light and electron microscopy (CLEM). We found that a subset of SIF is composed of double membranes that enclose portions of host cell cytosol and cytoskeletal filaments within its inner lumen. Despite some morphological similarities, we found that the formation of SIF double membranes is independent from autophagy and requires the function of the effector proteins SseF and SseG. The lumen of SIF network is accessible to various types of endocytosed material and our CLEM analysis of double membrane SIF demonstrated that fluid phase markers accumulate only between the inner and outer membrane of these structures, a space continual with endosomal lumen. Our work reveals how manipulation of the endosomal membrane system by an intracellular pathogen results in a unique tubular membrane compartmentalization of the host cell, generating a shielded niche permissive for intracellular proliferation of Salmonella. PMID:25254663

Histology and ultrastructure of the adrenal gland of the greater cane ...

African Journals Online (AJOL)

The results showed variations in the thickness of the zones of the cortex and medulla. Histological detail did not differ significantly from that of other rodents. Ultrastructural features showed typical adrenal gland zonation with capsule, cortical cells and medulla. In the cortex copious lipid droplets and myelin bodies were ...

Effects of water turbulence on variations in cell ultrastructure and metabolism of amino acids in the submersed macrophyte, Elodea nuttallii (Planch.) H. St. John.

Science.gov (United States)

Atapaththu, K S S; Miyagi, A; Atsuzawa, K; Kaneko, Y; Kawai-Yamada, M; Asaeda, T

2015-09-01

The interactions between macrophytes and water movement are not yet fully understood, and the causes responsible for the metabolic and ultrastructural variations in plant cells as a consequence of turbulence are largely unknown. In the present study, growth, metabolism and ultrastructural changes were evaluated in the aquatic macrophyte Elodea nuttallii, after exposure to turbulence for 30 days. The turbulence was generated with a vertically oscillating horizontal grid. The turbulence reduced plant growth, plasmolysed leaf cells and strengthened cell walls, and plants exposed to turbulence accumulated starch granules in stem chloroplasts. The size of the starch granules increased with the magnitude of the turbulence. Using capillary electrophoresis-mass spectrometry (CE-MS), analysis of the metabolome found metabolite accumulation in response to the turbulence. Asparagine was the dominant amino acid that was concentrated in stressed plants, and organic acids such as citrate, ascorbate, oxalate and γ-amino butyric acid (GABA) also accumulated in response to turbulence. These results indicate that turbulence caused severe stress that affected plant growth, cell ultrastructure and some metabolic functions of E. nuttallii. Our findings offer insights to explain the effects of water movement on the functions of aquatic plants. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

The Ultrastructural Effects of Sulfachloropyrazine on Toxoplasma Gondii Tachyzoites

Directory of Open Access Journals (Sweden)

YB Zeng

2013-03-01

Full Text Available Background: Toxoplasmosis is one of the most common parasitic infections of humans and other mammals. This study was aimed to understand the mechanism of action of veterinary medicine-sulfachlo­ropyrazine (SPZ, 99.97% against Toxoplasma gondii.Methods: T. gondii tachyzoites were soaked in PBS (as a control or SPZ (250 mg/mL for 2 h at 37 °C. After being processed, any ultrastructural changes of the tachyzoites that had occurred were observed by Scanning Electron Microscopy (SEM and Transmission Electron Microscopy (TEM.Results: The tachyzoites from control groups with a uniform size had a smooth surface and intact cell or nuclear membranes. In addition, an oval-shaped nucleus, conoids and micronemes were also observed. By contrast, many parasites from the SPZ-treated groups were detrimentally affected by the treatment. Some appeared to be of the vacuolization in their cytoplasm, with the substantial reduc­tion in the number of dense granules and the blur of some organelles.Conclusion: The morphology and ultrastructure of tachyzoites can be affected significantly by SPZ, which might kill the parasite by inhibiting its energy metabolism, inducing apoptosis and damaging its structure. The study provides an experimental basis for further study on the mechanism of SPZ against T. gondii.

Ultrastructure of Proechinophthirus zumpti (Anoplura, Echinophthiriidae by scanning electron microscopy

Directory of Open Access Journals (Sweden)

Dolores del Carmen Castro

2002-09-01

Full Text Available The ultrastructure of Proechinophthirus zumpti Werneck, 1955, mainly the external chorionic features of the egg, is described through electronic microscopy techniques. This species was first cited in Argentina, infesting Arctocephalus australis (Zimmermann, 1873. The morphological adaptations of adults and nymphs are described in both species of Proechinophthirus parasitic on Otariidae: P. fluctus (Ferris, 1916 and P. zumpti.

Ultrastructural and functional abnormalities of mitochondria in cultivated fibroblasts from α -mannosidosis patiens

Czech Academy of Sciences Publication Activity Database

Brantová, O.; Asfaw, B.; Sládková, J.; Poupětová, H.; Živný, J.; Magner, M.; Krůšek, Jan; Veselá, K.; Hansíková, H.; Ledvinová, J.; Tesařová, M.; Zeman, J.

2009-01-01

Roč. 64, č. 2 (2009), s. 394-401 ISSN 0006-3088 Institutional research plan: CEZ:AV0Z50110509 Keywords : mitochondria * endoplasmatic reticulum * ultrastructure Subject RIV: ED - Physiology Impact factor: 0.617, year: 2009

[Ultrastructure of epithelium and ciliary receptors in the parasitic turbellarian Urastoma cyprinae (Turbellaria, "Prolecithophora") and position of the species within Platyhelminthes].

Science.gov (United States)

Kornakova, E E

2002-01-01

be the preadaptation to the endoparasitic mode of life in Fecampiida. The differencies in ultrastructure of epithelium in U. cyprinae from the White Sea and from Mediterranean Sea (Noury-Sraïri e. a., 1990) may be explained by the differences in the method of fixation or by the parasitizing the another host--the mollusk Mytilus galloprovincialis. The ciliary receptors of five types were revealed in U. cyprinae (fig. 3, e, [symbol: see text]; 4; 5; 6). They differ in the shape and length of the ciliary rootlets and in the content of the nerve processes. All receptors lack of the real collars typical for the receptors of Neodermata. Urastoma is most close to the Neodermata amond parasitic turbellarians studied thus far, and the absence of collars in receptors of this species testifies that the collars are the veritable synapomorphy of the Neodermata. The diversity in the ultrastructure and possible functions of receptors correspond to the complicated adaptations of this species. The modern molecular data as well as the ultrastructural evidence attest that parasitic turbellarians of the genera Urastoma, Genostoma and Ichthyophaga are relatives and cannot be included in any turbellarian order known. Therefore Urastoma, Genostoma and Ichthyophaga have been erected in the separate order Urastomida ord. nov. The diagnosis of the new order is given.

Nannizziopsis guarroi infection in 2 Inland Bearded Dragons (Pogona vitticeps): clinical, cytologic, histologic, and ultrastructural aspects.

Science.gov (United States)

Le Donne, Viviana; Crossland, Nicholas; Brandão, João; Sokolova, Yuliya; Fowlkes, Natalie; Nevarez, Javier G; Langohr, Ingeborg M; Gaunt, Stephen D

2016-06-01

Chrysosporium-related infections have been increasingly reported in reptiles over the last 2 decades. In this report, we describe clinical, cytologic, histopathologic, and ultrastructural aspects of Chrysosporium-related infection in 2 Inland Bearded Dragons (Pogona vitticeps). Case 1 was presented for an enlarging raised lesion over the left eye and multiple additional masses over the dorsum. Case 2 was submitted to necropsy by the referring veterinarian for suspected yellow fungus disease. Impression smears of the nodules in case 1 revealed granulomatous to pyogranulomatous inflammation and many septate, variably long, 4-10 μm wide, often undulated hyphae, and very rare conidia. Postmortem impression smears of the superficial lesions of case 2 contained large numbers of solitary conidia and arthroconidia and low numbers of hyphae with similar morphology to case 1. Histopathology of the 2 cases revealed severe, multifocal, chronic, ulcerative, nodular pyogranulomatous dermatitis, with myriad intralesional septate hyphae, and arthroconidia. Fungal culture and molecular sequencing in both cases indicated infection with Nannizziopsis guarroi. © 2016 American Society for Veterinary Clinical Pathology.

The myocardial microangiopathy in human and experimental diabetes mellitus. (A microscopic, ultrastructural, morphometric and computer-assisted symbolic-logic analysis).

Science.gov (United States)

Taşcă, C; Stefăneanu, L; Vasilescu, C

1986-01-01

The following microscopical aspects were found in the small intramural arteries in the myocardium of 30 diabetic patients: endothelial proliferations with focal protuberances leading to partial narrowing of the lumen, increased thickness of the arterial wall due to fibrosis and accumulations of neutral mucopolysaccharides: alteration of elastic fibres. Morphometrically, the arterial wall thickness and the arterial diameter were increased whereas the arterial density decreased in the diabetic heart. In 25 rats with streptozotocin-induced diabetes the small intramyocardial arteries were investigated at 11 to 40 weeks of diabetic state. Using morphometrical analysis a constant increase of arterial wall thickness paralleling the diabetes duration was found. Microscopically, the lesions consist in endothelial proliferation with bridging across the vascular lumen and slight perivascular and diffuse fibrosis. Ultrastructurally, the capillary basal lamina was thickened in the diabetic myocardium. In order to investigate the morphometrical data we used symbolic-logic as a decision method, by applying an original computer program based on the Quine-McCluskey algorithm. All our results together with the final symbolic-logic expression suggest that damage of the small intramyocardial arteries plays an important role in the pathogenesis of diabetic cardiomyopathy.

Ultrastructural evaluation of gingival connective tissue in hereditary gingival fibromatosis.

Science.gov (United States)

Pêgo, Sabina Pena B; de Faria, Paulo Rogério; Santos, Luis Antônio N; Coletta, Ricardo D; de Aquino, Sibele Nascimento; Martelli-Júnior, Hercílio

2016-07-01

To describe the ultrastructural features of hereditary gingival fibromatosis (HGF) in affected family members and compare microscopic findings with normal gingival (NG) tissue. Gingival tissue samples from nine patients with HGF from five unrelated families were evaluated by transmission electron microscopy. Nine NG tissue samples were used for comparison. Areas containing collagen fibrils forming loops and folds were observed in both groups, whereas oxytalan fibers were frequently identified in the HGF group. The diameter of collagen fibrils and the interfibrillar space among them were more uniform in the NG group than in the HGF group. Fibroblasts were the most common cells found in both the HGF and NG groups and exhibited enlarged, rough endoplasmic reticulum, mitochondria with well-preserved crests, conspicuous nucleoli, and euchromatic chromatin. Other cells, such as mast cells, plasma cells, and macrophages, were also observed. HGF tissues had ultrastructural characteristics that were very similar to those of NG tissues. Oxytalan fibers were observed more frequently in the HGF samples than in the NG samples. Other studies of HGF in patients from different families should be performed to better understand the pathogenesis of this hereditary condition. Copyright © 2016 Elsevier Inc. All rights reserved.

Ultrastructural analysis of root canal dentine irradiated with 980-nm diode laser energy at different parameters.

Science.gov (United States)

Marchesan, Melissa Andréia; Brugnera-Junior, Aldo; Souza-Gabriel, Aline Evangelista; Correa-Silva, Silvio Rocha; Sousa-Neto, Manoel D

2008-06-01

The purpose of this in vitro study was to investigate using the scanning electron microscope (SEM) the ultrastructural morphological changes of the radicular dentine surface after irradiation with 980-nm diode laser energy at different parameters and angles of incidence. There have been limited reports on the effects of diode laser irradiation at 980 nm on radicular dentin morphology. Seventy-two maxillary canines were sectioned and roots were biomechanically prepared using K3 rotary instruments. The teeth were irrigated with 2 mL of distilled water between files and final irrigation was performed with 10 mL of distilled water. The teeth were then randomly divided into five groups (n = 8 each) according to their diode laser parameters: Group 1: no irradiation (control); group 2: 1.5 W/continuous wave (CW) emission (the manufacturer's parameters); group 3: 1.5 W/100 Hz; group 4: 3 W/CW; and group 5: 3 W/100 Hz. Laser energy was applied with helicoid movements (parallel to the canal walls) for 20 sec. Eight additional teeth for each group were endodontically prepared and split longitudinally and irradiation was applied perpendicularly to the root surface. Statistical analysis showed no difference between the root canal thirds irradiated with the 980-nm diode laser, and similar results between the parameters 1.5 W/CW and 3 W/100 Hz (p > 0.05). When considering different output powers and delivery modes our results showed that changes varied from smear layer removal to dentine fusion.

Ultra-structural changes and expression of chondrogenic and hypertrophic genes during chondrogenic differentiation of mesenchymal stromal cells in alginate beads

Directory of Open Access Journals (Sweden)

Havva Dashtdar

2016-03-01

Full Text Available Chondrogenic differentiation of mesenchymal stromal cells (MSCs in the form of pellet culture and encapsulation in alginate beads has been widely used as conventional model for in vitro chondrogenesis. However, comparative characterization between differentiation, hypertrophic markers, cell adhesion molecule and ultrastructural changes during alginate and pellet culture has not been described. Hence, the present study was conducted comparing MSCs cultured in pellet and alginate beads with monolayer culture. qPCR was performed to assess the expression of chondrogenic, hypertrophic, and cell adhesion molecule genes, whereas transmission electron microscopy (TEM was used to assess the ultrastructural changes. In addition, immunocytochemistry for Collagen type II and aggrecan and glycosaminoglycan (GAG analysis were performed. Our results indicate that pellet and alginate bead cultures were necessary for chondrogenic differentiation of MSC. It also indicates that cultures using alginate bead demonstrated significantly higher (p < 0.05 chondrogenic but lower hypertrophic (p < 0.05 gene expressions as compared with pellet cultures. N-cadherin and N-CAM1 expression were up-regulated in second and third weeks of culture and were comparable between the alginate bead and pellet culture groups, respectively. TEM images demonstrated ultrastructural changes resembling cell death in pellet cultures. Our results indicate that using alginate beads, MSCs express higher chondrogenic but lower hypertrophic gene expression. Enhanced production of extracellular matrix and cell adhesion molecules was also observed in this group. These findings suggest that alginate bead culture may serve as a superior chondrogenic model, whereas pellet culture is more appropriate as a hypertrophic model of chondrogenesis.

Form follows function: ultrastructure of different morphotypes of Physarum polycephalum

Science.gov (United States)

Oettmeier, Christina; Lee, Jonghyun; Döbereiner, Hans-Günther

2018-04-01

The multinucleate, unicellular slime mold Physarum polycephalum is a highly motile and morphologically diverse giant amoeba. Despite being brainless and lacking neurons, it exhibits ‘smart’ behavior. There is considerable interest in describing such traits and to investigate the underlying mechanochemical patterns which may hint at universal principles of behavior and decision-making. Furthermore, the slime mold’s mechanism of locomotion is unique. It resembles amoeboid movement, but differs from the locomotion of other amoebae in many ways, e.g. in their much larger size and lack of lobopodia. These two aspects, behavior and locomotion, are linked by the cytoskeleton and the overall morphology of P. polycephalum. In this paper, we present a structural analysis of different growth forms (micro-, meso- and macroplasmodia) by transmission electron microscopy (TEM), scanning electron microscopy (SEM), light microscopy, and fluorescence microscopy of F-actin. With these detailed investigations of cellular ultrastructure and morphology, we provide the basis for the analysis of, e.g. viscoelastic and rheological measurements. Our data also provide structural details for the many models that have been constructed for the understanding of locomotion. We conclude that morphological information is vital for the assessment and measurement of material properties.

Autoradiographic and ultrastructural studies on the human fibro-atheromatous plaque

Energy Technology Data Exchange (ETDEWEB)

Villaschi, S.; Spagnoli, L.G. (Universita degli Studi, Rome (Italy). Istituto di Anatomia ed Istologia Patologica)

1983-07-01

Foam cells, either myogenic or macrophagic, are commonly detected in experimental and human fibro-atheromatous plaques. Their role in human atherosclerosis is not yet understood. This paper reports on a preliminary autoradiographic study combined with ultrastructural observations in the human fibro-atheromatous plaque. Most of the autoradiographic silver grains appeared on foam cells and monocytelike cells, thus suggesting a local proliferation of these cells.

Autoradiographic and ultrastructural studies on the human fibro-atheromatous plaque

International Nuclear Information System (INIS)

Villaschi, Sergio; Spagnoli, L.G.

1983-01-01

Foam cells, either myogenic or macrophagic, are commonly detected in experimental and human fibro-atheromatous plaques. Their role in human atherosclerosis is not yet understood. This paper reports on a preliminary autoradiographic study combined with ultrastructural observations in the human fibro-atheromatous plaque. Most of the autoradiographic silver grains appeared on foam cells and monocytelike cells, thus suggesting a local proliferation of these cells. (author)

An ultrastructural study of the chromatoid body in planarian regenerative cells

International Nuclear Information System (INIS)

Hori, Isao

1982-01-01

The present paper deals with the ultrastructural changes of chromatoid bodies in planarian regenerative cells under normal and experimental conditions. A close relationship was usually observed between chromatoid bodies and pore regions of the nuclear envelope in these cells. The chromatoid bodies continued to decrease in size during cytodifferentiation of regenerative cells, though they did not disappear entirely throughout the regeneration processes. Cytochemistry and [ 3 H]uridine autoradiography have shown that the chromatoid body contains RNA. The typical morphological effect of actinomycin D became apparent in three organelles, i.e., nucleolus, polysome and chromatoid body. Ultrastructural changes in nucleoli were observed to occur after actinomycin treatment (20 μg/ml). The exposure to a higher dose of actinomycin (50 μg/ml) caused a decay of chromatoid bodies while nuclear envelopes retained numerous pores. Both the nucleoli and the chromatoid bodies disappeared in the sequential stages. Within the cytoplasm of such cells disintegration of a polysomal pattern was correlated with the disappearance of chromatoid bodies. The significance of the planarian chromatoid body is discussed in relation to differentiation of the regenerative cells. (author)

Ultrastructural studies on variants of Streptomyces SP-765 obtained after gamma irradiation

International Nuclear Information System (INIS)

Spasova, D.I.; Krystev, Kh.I.; Todorov, I.O.; Dzhedzheva, G.M.; Popov, M.S.

1988-01-01

The study has been carried out with two variants of Streptomyces SP-765, gray and olygosporous, obtained after 1000 Gy gamma irradiation of spore suspension from the initial strain. The gray variant has chains of spores which are oval or oblong with rounded-off edges. Sporulation is highly inhibited in the olygosporous variant. Eleven electron-microscopic pictures of ultrathin sections from colonies of the two variants are presented. The gray variant reveals the presence of a large number of lyzed cells, spores, and scarce vegetative cells; typical of the lyzed cells are the spherical and highly osmiophilic formations on the outer and inner surface of their cytoplasmic membrane. The oligosporous variant shows lyzed cells of various sizes, cells void of content with thick walls, relativelly small number of vegetative cells and individual wall-less cells, shperoplast and protoplast formation, lamellar membrane structure of nearly all cells. Both lyzed and vegetable cells have individual anomalous form containing daughter cells. The conclusion is made that gray and oligosporous variants of Streptomyces SP-765, obtained after irradiation of its spores, possess different ultrastructural organization

Ab interno trabeculectomy: ultrastructural evidence and early tissue response in a human eye.

Science.gov (United States)

Ferrari, Ettore; Ortolani, Fulvia; Petrelli, Lucia; Contin, Magali; Pognuz, Derri Roman; Marchini, Maurizio; Bandello, Francesco

2007-10-01

To report the results of ultrastructural analysis of the postoperative effects of ab interno trabeculectomy in a human eye. Department of Ophthalmology, Palmanova Hospital, Palmanova, Udine, Italy. A 60-year-old woman with cataract and glaucoma had enucleation for a choroidal melanoma 10 days after ab interno trabeculectomy combined with phacoemulsification. A second ab interno trabeculectomy was performed after enucleation to evaluate the outcomes of the previous trabeculectomy. Light and transmission electron microscopy analyses were performed on samples excised from areas (1) not subjected to a procedure (control samples), (2) that had ab interno trabeculectomy before enucleation, and (3) that had ab interno trabeculectomy immediately after enucleation. Control samples showed normal trabecular features. Semithin sections of all ab interno trabeculectomy samples showed full-thickness removal of trabeculum segments, with Schlemm's canal lumen opening into the anterior chamber and apparent preservation of the adjacent structures. On ultrathin sections of samples that had ab interno trabeculectomy before enucleation, the endothelium lining the outer wall of Schlemm's canal and other angle components showed intact ultrastructural features. In trabecular beams that were not removed, the extracellular matrix appeared to have maintained its fine texture and was free of activated fibroblasts or leucocyte infiltrates. Observations confirm that ab interno trabeculectomy causes direct communication between Schlemm's canal lumen and the anterior chamber in vivo and immediately after enucleation during the early postoperative period. The absence of an evident inflammatory reaction in the examined case should be considered with caution because of possible tumor-induced immune suppression.

Observations on the anterior testicular ducts in snakes with emphasis on sea snakes and ultrastructure in the yellow-bellied sea snake, Pelamis platurus.

Science.gov (United States)

Sever, David M; Freeborn, Layla R

2012-03-01

The anterior testicular ducts of squamates transport sperm from the seminiferous tubules to the ductus deferens. These ducts consist of the rete testis, ductuli efferentes, and ductus epididymis. Many histological and a few ultrastructural studies of the squamate reproductive tract exist, but none concern the Hydrophiidae, the sea snakes and sea kraits. In this study, we describe the anterior testicular ducts of six species of hydrophiid snakes as well as representatives from the Elapidae, Homolapsidae, Leptotyphlopidae, and Uropeltidae. In addition, we examine the ultrastructure of these ducts in the yellow-bellied Sea Snake, Pelamis platurus, only the third such study on snakes. The anterior testicular ducts are similar in histology in all species examined. The rete testis is simple squamous or cuboidal epithelium and transports sperm from the seminiferous tubules to the ductuli efferentes in the extratesticular epididymal sheath. The ductuli efferentes are branched, convoluted tubules composed of simple cuboidal, ciliated epithelium, and many species possess periodic acid-Schiff+ granules in the cytoplasm. The ductus epididymis at the light microscopy level appears composed of pseudostratified columnar epithelium. At the ultrastructural level, the rete testis and ductuli efferentes of P. platurus possess numerous small coated vesicles and lack secretory vacuoles. Apocrine blebs in the ductuli efferentes, however, indicate secretory activity, possibly by a constitutive pathway. Ultrastructure reveals three types of cells in the ductus epididymis of P. platurus: columnar principal cells, squamous basal cells, and mitochondria-rich apical cells. This is the first report of apical cells in a snake. In addition, occasional principal cells possess a single cilium, which has not been reported in reptiles previously but is known in some birds. Finally, the ductus epididymis of P. platurus differs from other snakes that have been studied in possession of apical, biphasic

Simultaneous detection of multiple targets for ultrastructural immunocytochemistry

Czech Academy of Sciences Publication Activity Database

Philimonenko, Vlada; Filimonenko, Anatolij; Šloufová, I.; Hrubý, Martin; Novotný, F.; Halbhuber, Z.; Krivjanská, M.; Nebesářová, Jana; Šlouf, Miroslav; Hozák, Pavel

2014-01-01

Roč. 141, č. 3 (2014), s. 229-239 ISSN 0948-6143 R&D Projects: GA AV ČR KAN200520704; GA TA ČR TE01020118; GA ČR GAP305/11/2232; GA MŠk LD12063 Grant - others:Human Frontier Science Program(FR) RGP0017/2013 Institutional research plan: CEZ:AV0Z50520514 Institutional support: RVO:61389013 ; RVO:60077344 ; RVO:68378050 Keywords : Immunolabeling * Metal nanoparticles * Electron microscopy * Cell nucleus * Ultrastructure * Phosphatidylinositol-4,5-Bisphosphate (PIP2) Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.927, year: 2013

Ultrastructure of central cell in female gametophyte of Castilleja wightii Elmer (Scrophulariaceae).

Science.gov (United States)

Ekici, Nuran; Dane, Feruzan; Olgun, Göksel

2013-09-01

Embryo sac cells are highly differentiated in plants. The central cell is one of the most important cells of the embryo sac. It forms endosperm by fusion with a sperm cell. Ultrastructure of the central cell in the mature embryo sac of Castilleja wightii was investigated in this study. Nucleolus which had a lot of vacuole in a large secondary nucleus and numerous dictyosomes, vesicles, mitochondria, amyloplasts in cytoplasm were seen in this cell. Also free ribosomes in the form of polysomes and large lipid bodies were detected in the cytoplasm. Numerous vacuoles of different size were observed and some of them had autophagic function. Both smooth and rough endoplasmic reticulums were seen. Although invaginations were seen in the plasmalemma of the central cell to the inside of the embryo sac, a thick cuticular layer was observed outer side on the cell wall. The aim of this study was to contribute studies about the ultrastructure of embryo sacs.

Changes of mitochondrial ultrastructure and function during ageing in mice and Drosophila.

Science.gov (United States)

Brandt, Tobias; Mourier, Arnaud; Tain, Luke S; Partridge, Linda; Larsson, Nils-Göran; Kühlbrandt, Werner

2017-07-12

Ageing is a progressive decline of intrinsic physiological functions. We examined the impact of ageing on the ultrastructure and function of mitochondria in mouse and fruit flies ( Drosophila melanogaster ) by electron cryo-tomography and respirometry. We discovered distinct age-related changes in both model organisms. Mitochondrial function and ultrastructure are maintained in mouse heart, whereas subpopulations of mitochondria from mouse liver show age-related changes in membrane morphology. Subpopulations of mitochondria from young and old mouse kidney resemble those described for apoptosis. In aged flies, respiratory activity is compromised and the production of peroxide radicals is increased. In about 50% of mitochondria from old flies, the inner membrane organization breaks down. This establishes a clear link between inner membrane architecture and functional decline. Mitochondria were affected by ageing to very different extents, depending on the organism and possibly on the degree to which tissues within the same organism are protected against mitochondrial damage.

Ultrastructure and molecular phylogeny of Calkinsia aureus: cellular identity of a novel clade of deep-sea euglenozoans with epibiotic bacteria

Directory of Open Access Journals (Sweden)

Leander Brian S

2009-01-01

Full Text Available Abstract Background The Euglenozoa is a large group of eukaryotic flagellates with diverse modes of nutrition. The group consists of three main subclades – euglenids, kinetoplastids and diplonemids – that have been confirmed with both molecular phylogenetic analyses and a combination of shared ultrastructural characteristics. Several poorly understood lineages of putative euglenozoans live in anoxic environments, such as Calkinsia aureus, and have yet to be characterized at the molecular and ultrastructural levels. Improved understanding of these lineages is expected to shed considerable light onto the ultrastructure of prokaryote-eukaryote symbioses and the associated cellular innovations found within the Euglenozoa and beyond. Results We collected Calkinsia aureus from core samples taken from the low-oxygen seafloor of the Santa Barbara Basin (580 – 592 m depth, California. These biflagellates were distinctively orange in color and covered with a dense array of elongated epibiotic bacteria. Serial TEM sections through individually prepared cells demonstrated that C. aureus shares derived ultrastructural features with other members of the Euglenozoa (e.g. the same paraxonemal rods, microtubular root system and extrusomes. However, C. aureus also possessed several novel ultrastructural systems, such as modified mitochondria (i.e. hydrogenosome-like, an "extrusomal pocket", a highly organized extracellular matrix beneath epibiotic bacteria and a complex flagellar transition zone. Molecular phylogenies inferred from SSU rDNA sequences demonstrated that C. aureus grouped strongly within the Euglenozoa and with several environmental sequences taken from low-oxygen sediments in various locations around the world. Conclusion Calkinsia aureus possesses all of the synapomorphies for the Euglenozoa, but lacks traits that are specific to any of the three previously recognized euglenozoan subgroups. Molecular phylogenetic analyses of C. aureus

Ultrastructural changes in spermatogonia of Wistar strain rats following acute whole-body X-ray exposure

Energy Technology Data Exchange (ETDEWEB)

Hrehorovsky, M; Horak, J [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie

1980-01-01

Changes in spermatogonia ultrastructure in rats of Wistar strain after single whole-body X-ray irradiation with 6.4 mC.kg/sup -1/, 25.8 mC.kg/sup -1/ and 51.6 mC.kg/sup -1/ respectively, were studied. Intracellular spaces were found between spermatogonia enlarged, nuclear membranes were bent, the pheripheral teritories of chromation were electronoptically denser, the morphology of nucleoli was changed, cytoplasm was vacuolised, mitochondria were damaged, the vacuolar dilatation of agranular endoplasmic reticulum was evident and electronoptically empty vacuoles near the Golgi complex occured 48 hours after single whole-body X-ray irradiation. Qualitative changes in the ultrastructure of individual types of spermatogonia after individual exposures were similar.

Growth, hydrolases and ultrastructure of Fusarium oxysporum as affected by phenolic rich extracts from several xerophytic plants.

Science.gov (United States)

Mohamed, Mahmoud S M; Saleh, Ahmed M; Abdel-Farid, Ibrahim B; El-Naggar, Sabry A

2017-09-01

Fusarium oxysporum, the causal agent of rot and wilt diseases, is one of the most detrimental phytopathogens for the productivity of many economic crops. The present study was conducted to evaluate the potentiality of some xerophytic plants as eco-friendly approach for management of F. oxysporum. Phenolic rich extracts from five plants namely: Horwoodia dicksoniae, Citrullus colocynthis, Gypsophila capillaris, Pulicaria incisa and Rhanterium epapposum were examined in vitro. The different extracts showed high variability in their phenolic and flavonoid contents as well as total antioxidant capacity. A strong positive correlation existed between the antifungal activity of the tested extracts and their contents of both total phenolics and flavonoids (r values are 0.91 and 0.82, respectively). Extract of P. incisa was the most effective in reducing the mycelial growth (IC 50 =0.92mg/ml) and inhibiting the activities of CMCase, pectinase, amylase and protease by 36, 42, 58 and 55%, respectively. The high performance liquid chromatography analysis of P. incisa extract revealed the presence of eight phenolic acids along with five polyphenolic compounds. The flavonol, quercetin and its glycosides rutin and quercetrin were the most abundant followed by the phenolic acids, t-cinnamic, caffeic, ferulic and vanillic. P. incisa extract not only affects the growth and hydrolases of F. oxysporum but also induces ultrastructure changes in the mycelium, as revealed by transmission electron microscopy. To our knowledge, this is the first study to investigate the mechanisms underlying the antifungal activity of P. incisa. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of root restriction on the ultrastructure of phloem in grape ...

African Journals Online (AJOL)

Yomi

2011-12-28

Dec 28, 2011 ... spaces among PP cells in the minor veins occurred in leaves from plants subjected to root restriction than in controls (Figure 4C to E). DISCUSSION. Since structure is often a meaningful guide to function, the ultrastructure of phloem in leaves is expected to yield clues to the mechanisms of phloem loading ...

Ultrastructural localization of actin and actin-binding proteins in the nucleus

Czech Academy of Sciences Publication Activity Database

Dingová, Hana; Fukalová, Jana; Maninová, Miloslava; Philimonenko, Vlada; Hozák, Pavel

2009-01-01

Roč. 131, č. 3 (2009), s. 425-434 ISSN 0948-6143 R&D Projects: GA MŠk LC545 Grant - others:MŠk(CZ) LC06063 Program:LC Institutional research plan: CEZ:AV0Z50520514 Keywords : nuclear actin * ultrastructure * actin–binding proteins Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.021, year: 2009

Ultrastructure of the spermatozoon of the proteocephalidean cestode Proteocephalus torulosus (Batsch, 1786)

Czech Academy of Sciences Publication Activity Database

Bruňanská, Magdaléna; Nebesářová, Jana; Scholz, Tomáš

2003-01-01

Roč. 89, č. 5 (2003), s. 345-351 ISSN 0932-0113 R&D Projects: GA ČR GA524/01/1314 Institutional research plan: CEZ:AV0Z6022909 Keywords : cestoda * spermatozoon * ultrastructure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.000, year: 2003

Effects of Lead on Ultrastructure of Isoetes sinensis Palmer (Isoetaceae, a Critically Endangered Species in China.

Directory of Open Access Journals (Sweden)

Guohua Ding

Full Text Available Isoetes sinensis Palmer (Isoetaceae is a critically endangered fern that is a marsh plant (that is an aquatic or amphibious plant in China. To evaluate damage or influence of lead (Pb on cell ultrastructure in I. sinensis, we used 2000mg·L-1 Pb(NO32 solution to treat I. sinensis for 35d, and used transmission electron microscope (TEM to observe the cell ultrastructure of leaf blades and roots of the plant. Our results indicated that Pb induced distinct changes of the organelles including chloroplast, mitochondria, nucleolus and vacuole. The level of damage organ was lower leaf > upper leaf > root The typical performance of the damages caused by lead shown that part of the nucleolus cracked; the cristae dilated, matrix vacuolized and membrane structure blurred in mitochondria; the vacuole cracked; grana lamella decreased, stroma lamella loosed, starch grains decreased, and membrane structure was disrupted in chloroplasts; Pb deposits were present on cell wall. The damages to chloroplasts and mitochondria were relatively severe, while damage to the nucleus was relatively lighter. The damage to the cell ultrastructure of leaf blades with direct contact with Pb was more severe than that without direct contact with Pb.

Capsaicin induced histological and ultrastructural changes in the submandibular salivary gland of albino rats

Directory of Open Access Journals (Sweden)

Ahmed Mahmoud Halawa

2016-06-01

From the present work, it could be concluded that chronic capsaicin intake was associated with noticeable histological and ultrastructural changes in acini, granular convoluted tubules and excretory ducts of the SMSG in albino rats.

Ultrastructural, autoradiographic and electrophoretic examinations of Chara tomentosa spermiogenesis

Directory of Open Access Journals (Sweden)

Maria Kwiatkowska

2014-01-01

Full Text Available Ultrastructure of a spermatid nucleus changes many times during spermiogenesis. Condensed chromatin forms irregular clusters during phases I-II, a continuous ring adjacent to a nuclear envelope during phases III-V and a network occupying the whole nucleus during phase VI. In advanced spermiogenesis dense chromatin disappears and short randomly positioned fibrils arise, then long parallel ones are found (phase VIII which during phase IX form a lamellar structure. In mature spermatozoids (phase X chromatin becomes extremely condensed. 3H-arginine and 3H-lysine incorporation into spermatids during 2-min incubation is intensive during phases IN, decreases during phases VI, VII and becomes very low during phases VIII-IX. Capillary electrophoresis has shown that during Chara tomentosa spermiogenesis replacement of histones with basic proteins whose mobility is comparable to that of salmon protamines takes place. At the beginning of spermiogenesis core and linker histones are found in spermatids. During early spermiogenesis protamine-like proteins appear and their amount increases in late spermiogenesis when core histones are still present. In mature spermatozoids only protamine-like proteins represented by 3 fractions: 9.1 kDa, 9.6 kDa, 11.2 kDa are found. Disappearance of linker histones following their modification precedes disappearance of core histones. The results indicate that dynamic rearrangement of chromatin ultrastructure and aminoacid incorporation rate during spermiogenesis are reflected in basic nuclear protein changes.

The influence of gamma radiation on catheptic activity and on ultrastructure of lysosomes and postmortem skeletal muscle of poultry Gallus domesticus

International Nuclear Information System (INIS)

Ali, Mumtaz.

1975-01-01

A three-part study is presented dealing with radiation-induced release of cathepsins from isolated lysosomes, irradiation inactivation of cathepsins, and ultrastructural changes in irradiated lysosomes and skeletal muscle. After chicken liver lysosomes were irradiated with 0.1 to 1.0 Mrad of gamma radiation a decrease in absorbance at 540 nm of lysosomal suspensions and an increase of free enzyme activity due to a release of cathepsins were noted. Examination of irradiated isolated lysosomes by electron microscopy showed leakage of material from weak points in the lysosomal membrane. Examination of irradiated chicken pectoralis muscle revealed an increase in interfibrillar spaces and some breaks in the myofibres. (LL)

X-irradiation-induced nuclear lesions in cultured mammaliam cells: an ultrastructural analysis

International Nuclear Information System (INIS)

Barham, S.S.; Walters, R.A.

1978-01-01

Electron-dense chromatin aggregates, hereafter referred to as lesions, have been characterized morphologically within interphase nuclei of Chinese hamster cells (line CHO) after a single acute exposure to 400, 800, 1200, or 2000 rad of x irradiation. At all doses studied, lesions were observed only after termination of radiation-induced division delay. Cell profiles were scored by electron microscopy for the presence or absence of nuclear lesions at various times after irradiation. The mitotic fraction from each irradiated population was also scored for each sample by light and electron microscopy. From these data and from simultaneous cell-density counts for each sample, it is apparent that postirradiation cell division is a prerequisite to formation of interphase nuclear lesions. Irradiated cell populations blocked in mitosis by Colcemid beyond the normal period of postirradiation division-delay failed to display nuclear lesions until after Colcemid was removed and cell division was completed. Enzyme digestions of isolated nuclei from irradiated cells with DNase I, RNase A, and Pronase suggest that the nuclear lesions are comprised primarily of chromatin. Nucleolar lesions, as well as various aberrant morphological forms of nucleoli, were also observed in cell populations after the onset of postirradiation cell division during the first 72 hr following exposure to irradiation. Delayed radiation-induced ultrastructural alterations of the nucleus included the formation of cytoplasmic invaginations into the nuclear space and inclusions of membranes within nuclei

Ultrastructural features of Mimulus aurantiacus (Scrophulariaceae) pollen tubes in vivo

OpenAIRE

Ekici,Nuran; Dane,Feruzan; Olgun,Göksel

2009-01-01

The aim of this study is to give information on ultrastructure of in vivo pollen tubes of Mimulus aurantiacus which were collected from the Botanical Garden of the University of California at Berkeley. Materials were prepared according to electron microscopy methods and examined under Zeiss electron microscope. Four zones were examined in the pollen tubes of Mimulus aurantiacus. APICAL ZONE: Mitochondria, smooth endoplasmic reticulum, rough endoplasmic reticulum, dictyosomes and secretory ves...

Evidence of compositional and ultrastructural shifts during the development of calcareous tubes in the biofouling tubeworm, Hydroides elegans.

Science.gov (United States)

Chan, Vera Bin San; Vinn, Olev; Li, Chaoyi; Lu, Xingwen; Kudryavtsev, Anatoliy B; Schopf, J William; Shih, Kaimin; Zhang, Tong; Thiyagarajan, Vengatesen

2015-03-01

The serpulid tubeworm, Hydroides elegans, is an ecologically and economically important species whose biology has been fairly well studied, especially in the context of larval development and settlement on man-made objects (biofouling). Nevertheless, ontogenetic changes associated with calcareous tube composition and structures have not yet been studied. Here, the ultrastructure and composition of the calcareous tubes built by H. elegans was examined in the three early calcifying juvenile stages and in the adult using XRD, FTIR, ICP-OES, SEM and Raman spectroscopy. Ontogenetic shifts in carbonate mineralogy were observed, for example, juvenile tubes contained more amorphous calcium carbonate and were predominantly aragonitic whereas adult tubes were bimineralic with considerably more calcite. The mineral composition gradually shifted during the tube development as shown by a decrease in Sr/Ca and an increase of Mg/Ca ratios with the tubeworm's age. The inner tube layer contained calcite, whereas the outer layer contained aragonite. Similarly, the tube complexity in terms of ultrastructure was associated with development. The sequential appearance of unoriented ultrastructures followed by oriented ultrastructures may reflect the evolutionary history of serpulid tube biominerals. As aragonitic structures are more susceptible to dissolution under ocean acidification (OA) conditions but are more difficult to be removed by anti-fouling treatments, the early developmental stages of the tubeworms may be vulnerable to OA but act as the important target for biofouling control. Copyright © 2015 Elsevier Inc. All rights reserved.

Ultrastructural characteristics of the uterine epithelium of aspidogastrean and digenean trematodes

Czech Academy of Sciences Publication Activity Database

Poddubnaya, L. G.; Levron, Céline; Gibson, D. I.

2011-01-01

Roč. 56, č. 2 (2011), 131-139 ISSN 1230-2821 R&D Projects: GA ČR GP524/07/P039; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Aspidogastrea * Digenea * Aspidogaster limacoides * Phyllodistomum angulatum * Azygia lucii * ultrastructure * uterus * septate junctions Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 0.789, year: 2011

Viability, ultrastructure and cytokinin metabolism of free and immobilized tobacco chloroplasts

Czech Academy of Sciences Publication Activity Database

Polanská, Lenka; Vičánková, Anna; Dobrev, Petre; Macháčková, Ivana; Vaňková, Radomíra

2004-01-01

Roč. 26, č. 20 (2004), s. 1549-1555 ISSN 0141-5492 R&D Projects: GA MŠk OC 840.20; GA MŠk LN00A081; GA ČR GA206/03/0369 Institutional research plan: CEZ:AV0Z5038910 Keywords : calcium alginate * chloroplast ultrastructure * cytokinin metabolism Subject RIV: ED - Physiology Impact factor: 0.849, year: 2004

Ultrastructural changes in mollicutes induced by the peptide antibiotic herbicolin A

DEFF Research Database (Denmark)

Birkelund, Svend; Freundt, A; Christiansen, Gunna

1986-01-01

Electron microscopy of negatively stained mycoplasma, ureaplasma, and acholeplasma cells showed ultrastructural changes after 10 min of treatment of the organisms with the peptide antibiotic herbicolin A in concentrations ranging from 10 micrograms/ml for Mycoplasma capricolum to 600 micrograms....../ml for Ureaplasma urealyticum. The morphological changes were shown to be reversible at low concentrations of the antibiotic but irreversible at high concentrations....

Ultrastructural immunocytochemical localization of chondroitin sulfate proteoglycan in Bruch's membrane of the rat

DEFF Research Database (Denmark)

Lin, W L; Essner, E; McCarthy, K J

1992-01-01

Two monoclonal antibodies (Mab 4D5 and 2D6) raised against the core protein of a basement membrane chondroitin sulfate proteoglycan from Reichert's membrane of the rat, were used for ultrastructural immunoperoxidase localization of this protein in Bruch's membrane of the rat. Immunoreactivity...

Ultrastructural study on experimental infection of rotavirus in a murine heterologous model

Directory of Open Access Journals (Sweden)

Selma Majerowicz

1994-09-01

Full Text Available Viral replication, histopathological and ultrastructural changes were observed for a period of nine days in the small intestine of suckling mice infected with a simian rotavirus (SA11. Samples taken from duodenum, jejunun and ileum were prepared for light microscopy, transmission and scanning electron microscopy analysis. Histopathologic effect could be detected within 8 hr post-infection, when only a few altered cells were observed. Damage was extensive after 16 hr post-infection, showing swollen enterocytes and reduced and irregularly oriented microvilli at intestinal villi tips. Virus particles were detected at 16 and 48 hr post-infection, budding from the viroplasm into the rough endoplasmic reticulum cisternae in ileum enterocytes. Clear evidence of viral replication, observed by electron microscopy was not described before in heterologous murine models. Regeneration of the intestinal villi began at the third day post-infection. Despite some differences observed in clinical symptoms and microscopic analysis of homologous and heterologous rotavirus infections, we concluded that mechanisms of heterologous rotavirus infection in mice follow similar patterns to those observed in the homologous models.

Light affects the chloroplast ultrastructure and post-storage photosynthetic performance of watermelon (Citrullus lanatus) plug seedlings.

Science.gov (United States)

Duan, Qingqing; Jiang, Wu; Ding, Ming; Lin, Ye; Huang, Danfeng

2014-01-01

Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] plug seedlings were stored at 15°C in the light at a photosynthetic photon flux density of 15 µmol·m(-2)·s(-1) or in darkness for 6 days, to evaluate their chloroplast ultrastructure, and associated photosynthetic characteristics. Storage in the dark caused swelling, disordered granal arrangement, and starch grain disappearance in the chloroplasts. In contrast, the chloroplasts stored in the light were relatively normal. As a result, the light-stored seedlings had a significantly higher chlorophyll content, Fv/Fm, and Pn than did dark-stored seedlings. Regardless of whether the seedlings were stored in light or darkness, the Gs and Ls of the seedlings significantly decreased, while the Ci obviously increased when the Pn decreased after 6 days of storage. This result suggests that the decreased Pn is not solely a stomatal effect, as the effects on the chloroplasts contributed to this photosynthetic inhibition. Six days after transplanting, seedlings that were stored in the light or darkness for 2 or 4 days showed complete recovery of chloroplast ultrastructure, chlorophyll content, Fv/Fm, Gs and Pn. When the storage period increased to 6 days, the dark-stored seedlings had a significantly lower Fv/Fm and Pn than the light-stored and control seedlings 6 days after transplanting, which was mainly ascribed to incomplete recovery of chloroplast ultrastructure. Furthermore, the light-stored seedlings exhibited a significantly higher shoot dry weight during storage and a higher percentage dry weight increase after transplanting than the dark-stored seedlings. These effects were enhanced by prolonged storage (4 to 6 days). This study demonstrated that dim light during storage is beneficial for maintaining chloroplast ultrastructure as well as photosynthetic efficiency in watermelon seedlings, thus contributing to the rapid recovery of post-storage photosynthetic performance, which ensures the transplant quality

Sperm ultrastructure of shrimps from the family Penaeidae (Crustacea: Dendrobranchiata) in a phylogenetic context.

Science.gov (United States)

Camargo, Tavani Rocha; Rossi, Natalia; Castilho, Antonio L; Costa, Rogério C; Mantelatto, Fernando L; Zara, Fernando José

2017-07-01

We describe the sperm ultrastructure of six penaeid species, including at least one member of each tribe (Penaeini, Parapenaeini and Trachypenaeini). Fragments of the vas deferens of the Penaeidae Farfantepenaeus brasiliensis, Farfantepenaeus paulensis, Litopenaeus schmitti, Parapenaeus americanus, Rimapenaeus constrictus and Xiphopenaeus kroyeri were fixed and processed according to the routine for transmission electron microscopy. The morphological results were contextualized in an evolutionary perspective using molecular markers for the phylogenetic reconstruction of this group. A phylogram was proposed by Bayesian inference based on 1007 bp of 33 sequences of the combined genes (16S rDNA and COI mtDNA) from 27 dendrobranchiate specimens. Our findings show that morphological differences in the sperm ultrastructures of members among the tribes of Penaeidae can be used as a baseline to understand their evolutionary relationships. Individuals from the Penaeini tribe show plesiomorphic characteristics in the sperm ultrastructure compared to the Trachypenaeini tribe from which they were derived, such as shrimp from family Sicyoniidae. The morphological complexity of the sperm of the different penaeid members corroborated with the genetic phylogeny, which showed different clades for each tribe and the close relationship with Sicyoniidae. The sperm features of the selected species studied here reflected their evolutionary history. These features confirm the previous phylogenetic hypothesis and question the monophyly of Penaeidae, which should be verified in the future with a more complete set of representative members of each tribe. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of Cistanche Desertica Polysaccharides on Learning and Memory Functions and Ultrastructure of Cerebral Neurons in Experimental Aging Mice

Institute of Scientific and Technical Information of China (English)

孙云; 邓杨梅; 王德俊; 沈春锋; 刘晓梅; 张洪泉

2001-01-01

To observe the effects of Cistanche desertica polysaccharides (CDP) on the learning and memory functions and cerebral ultrastructure in experimental aging mice. Methods: CDP was administrated intragastrically 50 or 100 mg/kg per day for 64 successive days to experimental aging model mice induced by D-galactose, then the learning and memory functions of mice were estimated by step-down test and Y-maze test; organelles of brain tissue and cerebral ultrastructure were observed by transmission electron microscope and physical strength was determined by swimming test. Results: CDP could obviously enhance the learning and memory functions (P＜0.01) and prolong the swimming time (P＜0.05), decrease the number of lipofuscin and slow down the degeneration of mitochondria in neurons(P＜0.05), and improve the degeneration of cerebral ultra-structure in aging mice. Conclusion: CDP could improve the impaired physiological function and alleviate cerebral morphological change in experimental aging mice.

Ultrastructure and autoradiography of dormant and activated parenchyma of Helianthus tuberosus

International Nuclear Information System (INIS)

Favali, M.A.; Sartorato, P.; Serafini-Fracassini, D.

1984-01-01

Parenchyma cells of dormant tubers of Helianthus tuberosus L. cv. OB 1 (Jerusalem artichoke) contain a very low amount of hormones, therefore they respond to 2.4-D or IAA treatment by dividing and synthesizing RNA, DNA, and polyamines. In particular the activation of the dormant tissues induces an early synthesis of DNA, which reaches the maximum at 3 hours, much before the beginning of the S phase (12 hours). By supplying [6- 3 H] thymidine and carrying out electron microscopic autoradiography, we were able to determine that plastids and mitochondria were the organelles responsible for this early synthesis while the DNA in the nucleus first appeared labeled at 15 hours. In addition, ultrastructural observations carried out to compare the dormant cells with activated ones, showed an increase in the nucleolar volume, a different organization of the tubular complex of the plastids and several other ultrastructural changes which indicate that at 3 hours some fundamental metabolic processes are already active; they become even more evident later on. The implication of these results in the physiology of the tuber cells during activation are discussed. (Author)

Ultrastructure and autoradiography of dormant and activated parenchyma of Helianthus tuberosus

Energy Technology Data Exchange (ETDEWEB)

Favali, M.A.; Sartorato, P. (Padua Univ. (Italy)); Serafini-Fracassini, D. (Bologna Univ. (Italy))

1984-01-01

Parenchyma cells of dormant tubers of Helianthus tuberosus L. cv. OB/sup 1/ (Jerusalem artichoke) contain a very low amount of hormones, therefore they respond to 2.4-D or IAA treatment by dividing and synthesizing RNA, DNA, and polyamines. In particular the activation of the dormant tissues induces an early synthesis of DNA, which reaches the maximum at 3 hours, much before the beginning of the S phase (12 hours). By supplying (6-/sup 3/H) thymidine and carrying out electron microscopic autoradiography, we were able to determine that plastids and mitochondria were the organelles responsible for this early synthesis while the DNA in the nucleus first appeared labeled at 15 hours. In addition, ultrastructural observations carried out to compare the dormant cells with activated ones, showed an increase in the nucleolar volume, a different organization of the tubular complex of the plastids and several other ultrastructural changes which indicate that at 3 hours some fundamental metabolic processes are already active; they become even more evident later on. The implication of these results in the physiology of the tuber cells during activation are discussed.

Ultrastructural alterations in hypoxic EMT-6/RO cells treated with misonidazole

International Nuclear Information System (INIS)

Wilbur, D.C.; Mulcahy, R.T.

1984-01-01

Ultrastructural alterations in hypoxic EMT-6 tumor cells were quantitatively analyzed as a function of time in the presence and absence of 1.0mM MISO. Control and MISO-treated monolayer cultures were maintained in hypoxic chambers at 37 0 C. At intervals after initiation of hypoxia, the cells were fixed and prepared for electron microscopy. The major ultrastructural alterations observed in untreated and MISO-treated hypoxic cells included mitochondrial swelling and accumulation of cytoplasmic lipid vacuoles. Mean mitochondrial area and relative cytoplasmic area occupied by lipid vacuoles were determined morphometrically. Mitochondrial damage was also scored qualitatively based on distortions in configuration. In the absence of MISO both parameters of mitochondrial injury increased over a period of two hours, after which little further change was noted. A progressive increase in lipid vacuolization was also seen. In the presence of MISO, mitochondrial swelling and lipid vacuole formation were significantly increased. The proportion of irreversibly damaged mitochondria was markedly enhanced. MISO treatment also accelerated the expression of these changes. The accelerated expression of hypoxic-related injury in MISO treated cells suggests that cytotoxicity is related to accentuation of hypoxic injury, perhaps by inhibition of glycolysis

An ultrastructural analysis of the effects of ethanol self-administration on the hypothalamic paraventricular nucleus in rhesus macaques

Directory of Open Access Journals (Sweden)

Vanessa Anne Jimenez

2015-07-01

Full Text Available A bidirectional relationship between stress and alcohol exists whereby stressful events are comorbid with problematic alcohol use and prolonged alcohol exposure results in adaptations of the physiological stress response. Endocrine response to stress is initiated in the hypothalamic paraventricular nucleus (PVN with the synthesis and release of corticotropin-releasing hormone (CRH and arginine-vasopressin (AVP. Alterations in CRH and AVP following long-term alcohol exposure in rodents is well demonstrated, however little is known about the response to alcohol in primates or the mechanisms of adaptation. We hypothesized that long-term alcohol self-administration in nonhuman primates would lead to ultrastructural changes in the PVN underlying adaptation to chronic alcohol. Double-label immunogold electron microscopy was used to measure presynaptic GABA and glutamate density within synaptic terminals contacting CRH- and AVP-immunoreactive dendrites. Additionally, pituitary-adrenal hormones (ACTH, cortisol, DHEA-s and aldosterone under two conditions (low and mild stress were compared before and after self-administration. All hormones were elevated in response to the mild stressor independent of alcohol consumption. The presynaptic glutamate density in recurrent (i.e., intra-hypothalamic CRH terminals was highly related to alcohol intake, and may be a permissive factor in increased drinking due to stress. Conversely, glutamate density within recurrent AVP terminals showed a trend-level increase following alcohol, but was not related to average daily consumption. Glutamate density in non-recurrent AVP terminals was related to aldosterone under the low stress condition while GABAergic density in this terminal population was related to water consumption. The results reveal distinct populations of presynaptic terminals whose glutamatergic or GABAergic density were uniquely related to water and alcohol consumption and circulating hormones.

Morphology and Ultrastructure of Brain Tissue and Fat Body from the Flesh Fly, Sarcophaga bullata Parker (Diptera: Sarcophagidae, Envenomated by the Ectoparasitic Wasp Nasonia vitripennis (Walker (Hymenoptera: Pteromalidae

Directory of Open Access Journals (Sweden)

David B. Rivers

2011-01-01

Full Text Available This study tested the hypothesis that venom from the ectoparasitic wasp Nasonia vitripennis targets brain tissue and fat body from its flesh fly host, Sarcophaga bullata. By 1 h postenvenomation, some brain neurons began to show irregularities in nuclear shape, and though they were predominately euchromatic, there was evidence of heterochromatin formation. Irregularity in the nuclear envelope became more prominent by 3 h after envenomation, as did the condensation of heterochromatin. The severity of ultrastructural changes continued to increase until at least 24 h after parasitoid attack. At this point, cellular swelling and extensive heterochromatic inclusions were evident, multivesicular bodies occurred in the cytoplasm of some cells, and the rough endoplasmic reticulum was dilated in many of the cells. Immunohistochemical staining revealed significant apoptosis in neurons located in brain tissues. By contrast, there was no evidence of any morphological or ultrastructural disturbances in fat body tissues up to 24 h after envenomation, nor did any of the cells display signs of cell death.

The effect of titanium dioxide nanoparticles on pulmonary surfactant function and ultrastructure

Directory of Open Access Journals (Sweden)

Braun Armin

2009-09-01

Full Text Available Abstract Background Pulmonary surfactant reduces surface tension and is present at the air-liquid interface in the alveoli where inhaled nanoparticles preferentially deposit. We investigated the effect of titanium dioxide (TiO2 nanosized particles (NSP and microsized particles (MSP on biophysical surfactant function after direct particle contact and after surface area cycling in vitro. In addition, TiO2 effects on surfactant ultrastructure were visualized. Methods A natural porcine surfactant preparation was incubated with increasing concentrations (50-500 μg/ml of TiO2 NSP or MSP, respectively. Biophysical surfactant function was measured in a pulsating bubble surfactometer before and after surface area cycling. Furthermore, surfactant ultrastructure was evaluated with a transmission electron microscope. Results TiO2 NSP, but not MSP, induced a surfactant dysfunction. For TiO2 NSP, adsorption surface tension (γads increased in a dose-dependent manner from 28.2 ± 2.3 mN/m to 33.2 ± 2.3 mN/m (p min slightly increased from 4.8 ± 0.5 mN/m up to 8.4 ± 1.3 mN/m (p 2 NSP concentrations. Presence of NSP during surface area cycling caused large and significant increases in both γads (63.6 ± 0.4 mN/m and γmin (21.1 ± 0.4 mN/m. Interestingly, TiO2 NSP induced aberrations in the surfactant ultrastructure. Lamellar body like structures were deformed and decreased in size. In addition, unilamellar vesicles were formed. Particle aggregates were found between single lamellae. Conclusion TiO2 nanosized particles can alter the structure and function of pulmonary surfactant. Particle size and surface area respectively play a critical role for the biophysical surfactant response in the lung.

Chromium-Induced Ultrastructural Changes and Oxidative Stress in Roots of Arabidopsis thaliana

Directory of Open Access Journals (Sweden)

Eleftherios P. Eleftheriou

2015-07-01

Full Text Available Chromium (Cr is an abundant heavy metal in nature, toxic to living organisms. As it is widely used in industry and leather tanning, it may accumulate locally at high concentrations, raising concerns for human health hazards. Though Cr effects have extensively been investigated in animals and mammals, in plants they are poorly understood. The present study was then undertaken to determine the ultrastructural malformations induced by hexavalent chromium [Cr(VI], the most toxic form provided as 100 μM potassium dichromate (K2Cr2O7, in the root tip cells of the model plant Arabidopsis thaliana. A concentration-dependent decrease of root growth and a time-dependent increase of dead cells, callose deposition, hydrogen peroxide (H2O2 production and peroxidase activity were found in Cr(VI-treated seedlings, mostly at the transition root zone. In the same zone, nuclei remained ultrastructurally unaffected, but in the meristematic zone some nuclei displayed bulbous outgrowths or contained tubular structures. Endoplasmic reticulum (ER was less affected under Cr(VI stress, but Golgi bodies appeared severely disintegrated. Moreover, mitochondria and plastids became spherical and displayed translucent stroma with diminished internal membranes, but noteworthy is that their double-membrane envelopes remained structurally intact. Starch grains and electron dense deposits occurred in the plastids. Amorphous material was also deposited in the cell walls, the middle lamella and the vacuoles. Some vacuoles were collapsed, but the tonoplast appeared integral. The plasma membrane was structurally unaffected and the cytoplasm contained opaque lipid droplets and dense electron deposits. All electron dense deposits presumably consisted of Cr that is sequestered from sensitive sites, thus contributing to metal tolerance. It is concluded that the ultrastructural changes are reactive oxygen species (ROS-correlated and the malformations observed are organelle specific.

Ultrastructure of embryonated eggs of the cestode Gyrocotyle urna (Gyrocotylidea) using cryo-methods

Czech Academy of Sciences Publication Activity Database

Levron, Céline; Scholz, Tomáš; Vancová, Marie; Kuchta, Roman; Conn, D. B.

2016-01-01

Roč. 135, č. 3 (2016), s. 279-289 ISSN 0720-213X R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Gyrocotylidea * Ultrastructure * Embryonic * Cryo-technique * Cestoda Subject RIV: EG - Zoology Impact factor: 1.038, year: 2016

Micromorphology and ultrastructure of the floral nectaries of Polemonium caeruleum L. (Polemoniaceae).

Science.gov (United States)

Chwil, Mirosława; Chwil, Stanisław

2012-10-01

The Polemoniaceae family forms flowers diverse in the terms of pollination methods and nectar types. The micromorphology of the nectary surface and the tissue structures as well as the ultrastructure of the cells of the floral nectaries in Polemonium caeruleum L. were examined using light, scanning and transmission electron microscopy. A bowl-shaped nectary, detached from the ovary, grows at its base. Its contour shows folds with depressions in the places where the stamens grow, forming five-lobed disc (synapomorphic character). Nectar is secreted through modified anomocytic stomata, which are formed in the epidermis covering the tip and the lateral wall of the projection located between the staminal filaments. The undulate nectary consists of a single-layered epidermis and three to nine layers of parenchymal cells. The cells of the nectary contain a dense cytoplasm, numerous plastids with an osmophilic stroma and starch grains, well-developed endoplasmic reticulum, as well as a large number of mitochondria interacting with the Golgi bodies. The ultrastructure of nectary cells indicates the granulocrine secretion mechanism and diversified transport of nectar.

Ginger and alpha lipoic acid ameliorate age-related ultrastructural changes in rat liver.

Science.gov (United States)

Mahmoud, Y I; Hegazy, H G

2016-01-01

Because of the important role that oxidative stress is thought to play in the aging process, antioxidants could be candidates for preventing its related pathologies. We investigated the ameliorative effects of two antioxidant supplements, ginger and alpha lipoic acid (ALA), on hepatic ultrastructural alterations in old rats. Livers of young (4 months) and old (24 months) Wistar rats were studied using transmission electron microscopy. Livers of old rats showed sinusoidal collapse and congestion, endothelial thickening and defenestration, and inconsistent perisinusoidal extracellular matrix deposition. Aged hepatocytes were characterized by hypertrophy, cytoplasmic vacuolization and a significant increase in the volume densities of the nuclei, mitochondria and dense bodies. Lipofuscin accumulation and decreased microvilli in bile canaliculi and space of Disse also were observed. The adverse alterations were ameliorated significantly by both ginger and ALA supplementation; ALA was more effective than ginger. Ginger and ALA appear to be promising anti-aging agents based on their amelioration of ultrastructural alterations in livers of old rats.

Ultrastructural age-related changes in the sensory corpuscles of the human genital skin.

Science.gov (United States)

Tammaro, A; Parisella, F R; Cavallotti, C; Persechino, S; Cavallotti, C

2013-01-01

In human genital skin the majority of superficial sensory corpuscles is represented by glomerular corpuscles. These corpuscles show an own morphology. Our aim is to compare the ultra-structure of superficial sensory corpuscles in the penis skin of younger and older subjects. In this report the ultra-structure of the sensitive corpuscle in the penis skin of the younger and older subjects was compared, showing that the genital skin of the older humans contains more simple complexes than the younger ones. Our findings support the view that the age-related changes that can be observed in human glomerular genital corpuscles are consistent with an increase of the simple complexes and a strong decrease of the poly-lamellar one in the older people. These findings demonstrate that human genital corpuscles underwent age-related changes. Moreover our morphological findings can be correlated in relation to the clinical evolution of the sensitivity in the genital skin.

Study on the ultrastructure of brain in rats prenatally exposed to tritiated water

International Nuclear Information System (INIS)

Yang Zhiyuan; Guo Yuefen; Lai Chixiang

1993-01-01

At 11th day of gestation, rats were intraperitoneally injected with HTO, the activity of which were 5.55 x 10 6 Bq/mL of body water and 5.55 x 10 5 Bq/mL of body water. In these conditions, the cumulative doses for 1-day-old and 18-day-old young rats were estimated to be 1.6-1.7 Gy and 0.16-0.17 Gy, respectively. Under the above-mentioned conditions, some significant injuries in the ultrastructure of the nucleus of neutron and of the cell apparatuses in the cytoplasm of the cerebral and cerebellar cortexes can be seen on the 1-day-old and 18-day-old young rats. When young rats were 90 days old, these injuries of ultrastructure in brain cells had not be observed but it was observed that the processes of neutroglia cells replenished the crevices in injured neutropilem of the cerebral and cerebellar cortex

Quantitative Proteomics Analysis Reveals Novel Insights into Mechanisms of Action of Long Noncoding RNA Hox Transcript Antisense Intergenic RNA (HOTAIR) in HeLa Cells*

Science.gov (United States)

Zheng, Peng; Xiong, Qian; Wu, Ying; Chen, Ying; Chen, Zhuo; Fleming, Joy; Gao, Ding; Bi, Lijun; Ge, Feng

2015-01-01

Long noncoding RNAs (lncRNAs), which have emerged in recent years as a new and crucial layer of gene regulators, regulate various biological processes such as carcinogenesis and metastasis. HOTAIR (Hox transcript antisense intergenic RNA), a lncRNA overexpressed in most human cancers, has been shown to be an oncogenic lncRNA. Here, we explored the role of HOTAIR in HeLa cells and searched for proteins regulated by HOTAIR. To understand the mechanism of action of HOTAIR from a systems perspective, we employed a quantitative proteomic strategy to systematically identify potential targets of HOTAIR. The expression of 170 proteins was significantly dys-regulated after inhibition of HOTAIR, implying that they could be potential targets of HOTAIR. Analysis of this data at the systems level revealed major changes in proteins involved in diverse cellular components, including the cytoskeleton and the respiratory chain. Further functional studies on vimentin (VIM), a key protein involved in the cytoskeleton, revealed that HOTAIR exerts its effects on migration and invasion of HeLa cells, at least in part, through the regulation of VIM expression. Inhibition of HOTAIR leads to mitochondrial dysfunction and ultrastructural alterations, suggesting a novel role of HOTAIR in maintaining mitochondrial function in cancer cells. Our results provide novel insights into the mechanisms underlying the function of HOTAIR in cancer cells. We expect that the methods used in this study will become an integral part of functional studies of lncRNAs. PMID:25762744

Spermiogenesis and spermatozoon ultrastructure of the paruterinid cestode Notopentorchis sp. (Cyclophyllidea)

Czech Academy of Sciences Publication Activity Database

Yoneva, A.; Levron, Céline; NIkolov, P. N.; Mizinska, Y.; Mariaux, J.; Georgiev, B. B.

2012-01-01

Roč. 111, č. 1 (2012), s. 135-142 ISSN 0932-0113 R&D Projects: GA ČR GBP505/12/G112 Institutional research plan: CEZ:AV0Z60220518 Keywords : INTESTINAL PARASITE * MATURE SPERMATOZOON * SPERMATOLOGICAL CHARACTERS * TAPEWORMS PLATYHELMINTHES * COMPARATIVE MORPHOLOGY * SPERM ULTRASTRUCTURE * ELECTRON MICROSCOPY * GOLDEN-HAMSTERS * FINE-STRUCTURE * VON LINSTOW Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.852, year: 2012

Spermatozoa of tapeworms (Platyhelminthes, Eucestoda): advances in ultrastructural and phylogenetic studies

Czech Academy of Sciences Publication Activity Database

Levron, Céline; Miquel, J.; Oros, Mikuláš; Scholz, Tomáš

2010-01-01

Roč. 85, č. 3 (2010), s. 523-543 ISSN 1464-7931 R&D Projects: GA ČR GP524/07/P039; GA ČR GA524/08/0885; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : spermatozoon * spermiogenesis * ultrastructure * phylogeny * classification * Eucestoda * Platyhelminthes * tapeworm Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 6.574, year: 2010

Effects of colchicine on the intestinal transport of endogenous lipid. Ultrastructural, biochemical, and radiochemical studies in fasting rats

International Nuclear Information System (INIS)

Pavelka, M.; Gangl, A.

1983-01-01

The involvement of microtubules in the transepithelial transport of exogenous lipid in intestinal absorptive cells has been suggested. Using electronmicroscopic, biochemical, and radiochemical methods, researchers have studied the effects of the antimicrotubular agent colchicine on the intestinal mucosa and on the intestinal transport of endogenous lipid of rats in the fasting state. After colchicine treatment, the concentration of triglycerides in intestinal mucosa of rats fasted for 24 h doubled, and electron microscopic studies showed a striking accumulation of lipid particles in absorptive epithelial cells of the tips of jejunal villi. These findings suggest that colchicine interferes with the intestinal transepithelial transport of endogenous lipoproteins. Additional studies, using an intraduodenal pulse injection of [ 14 C]linoleic acid, showed that colchicine does not affect the uptake of fatty acids by intestinal mucosa. However, it had divergent effects on fatty acid esterification, enhancing their incorporation into triglycerides relative to phospholipids, and caused a significant accumulation of endogenous diglycerides, triglycerides, and cholesterol esters within the absorptive intestinal epithelium. Detailed ultrastructural and morphometric studies revealed a decrease of visible microtubules, and a displacement of the smooth and rough endoplasmic reticulum and Golgi apparatus. Furthermore, it is shown that after colchicine treatment, microvilli appear at the lateral plasma membrane of intestinal absorptive cells, a change not previously reported to our knowledge. Thus, our study shows that colchicine causes significant changes in enterocyte ultrastructure and colchicine perturbs the reesterification of absorbed endogenous fatty acids and their secretion in the form of triglyceride-rich lipoproteins from the enterocyte

Ultrastructural Analysis and Long-term Evaluation of Composite-Zirconia Bond Strength.

Science.gov (United States)

Aboushelib, Moustafa N; Ragab, Hala; Arnaot, Mohamed

2018-01-01

To evaluate the influence of different aging techniques on zirconia-composite microtensile bond strength using different surface treatments over a 5-year follow-up period. Zirconia disks received three surface treatments: airborne-particle abrasion with 50-μm aluminum oxide particles, selective infiltration etching (SIE), or fusion sputtering (FS). The specimens were bonded to pre-aged composite disks using a composite cement containing phosphate monomers (Panavia F2.0). Bonded specimens were sectioned into microbars (1 x 1 x 6 mm) using a precision cutting machine, and all microbars received thermocycling (15,000 cycles between 5°C and 55°C). Initial microtensile bond strength was evaluated, and the test was repeated after storage in the following media for five years (artificial saliva, 20% ethanol, 5% NaOH, 4% acetic acid, and 5% phosphoric acid). The test was repeated every 12 months for 5 years. Scanning electron microscopic images were used to analyze the zirconia-composite interface. A repeated measures ANOVA and Bonferroni post-hoc tests were used to analyze the data (n = 20, α = 0.05). Significantly higher microtensile bond strength was observed for SIE compared to fusion sputtering and airborne particle abrasion. Five years of artificial aging resulted in significant reduction of zirconia-composite bond strength for all tested specimens. Zirconia-composite bond strength was more sensitive to storage in sodium hydroxide and phosphoric acid, while it was least affected when stored under saliva. These changes were related to the mechanism of ultra-structural interaction between surface treatment and adhesive, as deterioration of the hybrid layer (composite-infiltrated ceramic) was responsible for bond degeneration. Zirconia-composite bond strength was influenced by 5 years of artificial aging.

[Cellphone electromagnetic radiation damages the testicular ultrastructure of male rats].

Science.gov (United States)

Gao, Xiao-Hui; Hu, Hui-Rong; Ma, Xue-Lian; Chen, Jie; Zhang, Guo-Hong

2016-06-01

To investigate the influence of cellphone electromagnetic radiation (CER) on the testicular ultrastructure and the apoptosis of spermatogenic cells in male rats.atability, feasibility, applicability, and controllability in the construction of experimental animal models, we compared the major anatomic features of the penis of 20 adult beagle dogs with those of 10 adult men. Using microsurgical techniques, we performed cross-transplantation of the penis in the 20 (10 pairs) beagle dogs and observed the survival rate of the transplanted penises by FK506+MMF+MP immune induction. We compared the relevant indexes with those of the 10 cases of microsurgical replantation of the amputated penis. Thirty adult male SD rats were equally randomized into a 2 h CER, a 4 h CER, and a normal control group, the former two groups exposed to 30 days of 900 MHz CER for 2 and 4 hours a day, respectively, while the latter left untreated. Then the changes in the ultrastructure of the testis tissue were observed under the transmission electron microscope and the apoptosis of the spermatogenic cells was determined by TUNEL. Compared with the normal controls, the rats of the 2 h CER group showed swollen basement membrane of seminiferous tubules, separated tight junction of Sertoli cells, increased cell intervals, apparent vacuoles and medullization in some mitochondria, and increased apoptosis of spermatogenic cells, mainly the apoptosis of primary spermatocytes (P<0.05 ). In comparison with the 2 h CER group, the animals of the 4 h CER group exhibited swollen basement membrane of seminiferous tubules, more separated tight junction of Sertoli cells, wider cell intervals, incomplete membrane of spermatogonial cells, fragments of cytoplasm, nuclear pyknosis and notch, slight dilation of perinuclear space, abnormalities of intracellular mitochondria with vacuoles, fuzzy structure, and fusion or disappearance of some cristae, and increased damage of mitochondria and apoptosis of spermatogenic

The effects of freezing, storage, and thawing on cell compartment integrity and ultrastructure

DEFF Research Database (Denmark)

Prentø, P

1997-01-01

The effects of slow freezing and thawing on enzyme compartmentalization and ultrastructure were studied in rat liver slices frozen in dry ice, isopentane/ethanol-dry ice, or liquid nitrogen, and stored at -80 degrees C for 1-14 days. Non-frozen slices served as controls. Frozen liver slices were...

Transcriptome analysis and ultrastructure observation reveal that hawthorn fruit softening is due to cellulose/hemicellulose degradation

Directory of Open Access Journals (Sweden)

Jiayu Xu

2016-10-01

Full Text Available Softening, a common phenomenon in many fruits, is a well coordinated and genetically determined process. However, the process of flesh softening during ripening has rarely been described in hawthorn. In this study, we found that ‘Ruanrou Shanlihong 3 Hao’ fruits became softer during ripening, whereas ‘Qiu JinXing’ fruits remained hard. At late developmental stages, the firmness of ‘Ruanrou Shanlihong 3 Hao’ fruits rapidly declined, and that of ‘Qiu JinXing’ fruits remained essentially unchanged. According to transmission electron microscopy (TEM, the middle lamella of ‘Qiu JinXing’ and ‘Ruanrou Shanlihong 3 Hao’ fruit flesh was largely degraded as the fruits matured. Microfilaments in ‘Qiu JinXing’ flesh were arranged close together and were deep in color, whereas those in ‘Ruanrou Shanlihong 3 Hao’ fruit flesh were arranged loosely, partially degraded and light in color. RNA-Seq analysis yielded approximately 46.72 Gb of clean data and 72,837 unigenes. Galactose metabolism and pentose and glucuronate interconversions are involved in cell wall metabolism, play an important role in hawthorn texture. We identified 85 unigenes related to the cell wall between hard- and soft-fleshed hawthorn fruits. Based on data analysis and real-time PCR, we suggest that β-GAL and PE4 have important functions in early fruit softening. The genes Ffase, Gns, α-GAL, PE63, XTH and CWP, which are involved in cell wall degradation, are responsible for the different textures of hawthorn fruits. Thus, we hypothesize that the different textures of ‘Qiu JinXing’ and ‘Ruanrou Shanlihong 3 Hao’ fruits at maturity mainly result from cellulose/hemicelluloses degradation rather than from lamella degradation. Overall, we propose that different types of hydrolytic enzymes in cells interact to degrade the cell wall, resulting in ultramicroscopic Structure changes in the cell wall and, consequently, fruit softening. These results provide

Ultrastructural analysis of early toxic effects produced by bee venom phospholipase A2 and melittin in Sertoli cells in rats.

Science.gov (United States)

Tilinca, Mariana; Florea, Adrian

2018-01-01

In this study, we aimed to investigate the testicular toxicity of two molecules derived from bee venom (BV): phospholipase A2 (PlA2) and melittin (Mlt). Ultrastructural effects of purified BV PlA2 and Mlt were assessed consecutive to repeated dose (30 days) and acute toxicity studies. For the subchronic treatment, PlA2 and Mlt were injected in daily doses equivalent to those released by a bee sting (105 μg PlA2/kg/day and 350 μg Mlt/kg/day), while in the acute treatment their doses corresponded to those released by 100 bee stings (9.3 mg PlA2/kg and 31 mg Mlt/kg). Both PlA2 and Mlt affected the Leydig cells and the cells in seminiferous tubules, the Sertoli cells first of all. PlA2 injection resulted in detachment of the Sertoli cells from the surrounding cells, and extracellular vacuolations, cytoplasmic vacuolations in their basal region and in branches as well, detachment of spermatids, residual bodies and sometimes even spermatocytes into the lumen, changes that had a higher magnitude after the acute treatment. Mlt injection induced similar ultrastructural alterations, but more severe, including degeneration of cellular organelles and cellular necrosis, resulting into rarefaction of the seminiferous epithelium; the ultrastructural changes had a higher magnitude after the 30 repeated dose treatment. We concluded that either of the two molecules tested here, PlA2 and Mlt, were Sertoli cells toxicants at the used doses, and they participated both in the BV testicular toxicity. We consider the observed changes as part of a preceding mechanism of the more severe alterations produced by the BV. It also remains possible that these early unspecific changes reported here could represent the response of the SCs not only to the components of bee venom, but to molecules of other venoms as well. The Sertoli cells were the primary target of PlA2 and Mlt in the spermatogenic epithelium, and their alteration led to further degenerative changes of the germ cells. Since

Hematologic, cytochemical, ultrastructural, and molecular findings of Hepatozoon-infected flat-headed cats (Prionailurus planiceps).

Science.gov (United States)

Salakij, Chaleow; Salakij, Jarernsak; Narkkong, Nual-Anong; Sirinarumitr, Theerapol; Pattanarangsan, Rattapan

2008-03-01

The flat-headed cat (Prionailurus planiceps) is a small wild cat of Southeast Asia and is considered extremely endangered. Little is known about the hematologic values, blood cell morphology, or hemoparasites of this species in relation to other Felidae. The objective of this study was to report basic hematologic values and describe the light microscopic, cytochemical, and ultrastructural characteristics of blood cells in 2 wild-caught flat-headed cats. In addition, molecular analysis was done of a Hepatozoon organism found in the neutrophils of both cats. Blood samples were collected into EDTA from the cephalic vein. A CBC, manual differential count, manual reticulocyte count, cytochemical stains (Sudan black B [SBB], alpha-naphthyl acetate esterase [ANAE], and beta-glucuronidase), and scanning and transmission electron microscopy were done using standard methods. HCT was slightly lower and reticulocyte counts and red cell distribution width were higher than the expected values for other species of cats. Hepatozoon organisms were found in the cytoplasm of neutrophils in both cats, but the number of infected neutrophils was very low (1%-2%). Neutrophils stained strongly positive for SBB, but were negative for ANAE and beta-glucuronidase. Hepatozoon-infected neutrophils were negative for SBB, but focally positive for ANAE and beta-glucuronidase. By transmission electron microscopy, gamonts of Hepatozoon sp were observed in neutrophils, and rarely free in plasma. Infected neutrophils had fewer specific granules and more mitochondria compared with noninfected neutrophils. PCR products of partial 18S rRNA revealed that the isolate of Hepatozoon in the flat-headed cats was closely related to that of the frog Hepatozoon sp. These results add to our understanding of hematologic values and blood cell morphology in Hepatozoon-infected flat-headed cats as well as the molecular analysis of the Hepatozoon organism, and may be useful for the health management and evaluation of

Attenuation of endocrine-exocrine pancreatic communication in type 2 diabetes: pancreatic extracellular matrix ultrastructural abnormalities.

Science.gov (United States)

Hayden, Melvin R; Patel, Kamlesh; Habibi, Javad; Gupta, Deepa; Tekwani, Seema S; Whaley-Connell, Adam; Sowers, James R

2008-01-01

Ultrastructural observations reveal a continuous interstitial matrix connection between the endocrine and exocrine pancreas, which is lost due to fibrosis in rodent models and humans with type 2 diabetes mellitus (T2DM). Widening of the islet-exocrine interface appears to result in loss of desmosomes and adherens junctions between islet and acinar cells and is associated with hypercellularity consisting of pericytes and inflammatory cells in T2DM pancreatic tissue. Organized fibrillar collagen was closely associated with pericytes, which are known to differentiate into myofibroblasts-pancreatic stellate cells. Of importance, some pericyte cellular processes traverse both the connecting islet-exocrine interface and the endoacinar interstitium of the exocrine pancreas. Loss of cellular paracrine communication and extracellular matrix remodeling fibrosis in young animal models and humans may result in a dysfunctional insulino-acinar-ductal-incretin gut hormone axis, resulting in pancreatic insufficiency and glucagon-like peptide deficiency, which are known to exist in prediabetes and overt T2DM in humans.

DESCRIPTION OF ULTRASTRUCTURAL DAMAGES IN FROZEN-THAWED CANINE SPERMATOZOA DESCRIÇÃO DE DANOS ULTRAESTRUTURAIS EM ESPERMATOZOIDES CANINOS CONGELADOS-DESCONGELADOS

Directory of Open Access Journals (Sweden)

Viviane Helena Chirinéa

2009-07-01

Full Text Available In spite of the advances in transmission electronic microscopy (TEM, there are few studies presenting a systematic description of the canine spermatozoa and they are only focused on sperm cell heads. The goal of the present study was to describe ultrastructural appearance of canine fresh and frozen-thawed spermatozoa, focusing on damages induced by freezing-thawing in different sperm regions. Ten ejaculates from five proven stud dogs (two ejaculates/dog were collected, evaluated, extended in Tris-egg yolk-glycerol, frozen and stored in liquid nitrogen, and thawed six weeks later.  Samples were evaluated for progressive motility, morphology, and for ultrastructural analysis by TEM. Concerning to TEM, the most striking differences between fresh and frozen-thawed samples were observed over the mid-piece since the fresh spermatozoa showed a well preserved mid-piece. However, the frozen-thawed spermatozoa mid-piece showed signs of damage such as mitochondrial vacuolization. In conclusion, freezing-thawing processes using a Tris-egg yolk extender induce ultrastructural damages in head and mid-piece of canine sperm, affecting the mitochondrial ultrastructure besides.

KEY WORDS: Cryopreservation, dog, semen, ultrastructure.
Apesar dos avanços na microscopia eletrônica de transmissão (MET, existem poucos estudos apresentando uma descrição sistemática do espermatozoide canino, os quais estão focados apenas na cabeça espermática. Objetivou-se, com o presente estudo, descrever a aparência ultraestrutural do espermatozoide canino fresco e congelado-descongelado, enfocando os danos induzidos pela congelação e descongelação em diferentes regiões espermáticas. Dez ejaculados obtidos de cinco cães (dois ejaculados por cão foram coletados, avaliados e diluídos em Tris-gema-glicerol, congelados e armazenados em nitrogênio líquido, e descongelados seis semanas após. Avaliaram-se as amostras quanto à motilidade progressiva

Radiation induced cell death in cervical squamous cell carcinoma. An immunohistochemical and ultrastructural study

International Nuclear Information System (INIS)

Atari, Eio; Toda, Takayoshi; Sadi, A.M.; Egawa, Haruhiko; Moromizato, Hidehiko; Mamadi, T.; Kiyuna, Masaya

1998-01-01

To study the process of cell death in cervical squamous cell carcinoma (SCC) after radiation, an ultrastructural and immunohistochemical study was performed. Paraffin-embedded tissue blocks of biopsy samples pre- and post-radiation stage III SCC (n=15) were collected. Irradiation caused varying ultrastructural changes including nuclear and cytoplasmic disorganization suggesting cell necrosis. Immunohistochemically, the pre-radiation specimens showed no positive reaction for tumor necrosis factor-alpha (TNF-α), tumor necrosis factor-receptor (TNF-γ) or Fas. C-fos, p53 and bcl-2 showed positive reactions in only a few non-irradiated specimens. All of the irradiated specimens showed a positive reaction for TNF-α, and variable positive reactions were observed for TNF-γ, Fas, p53, c-fos and bcl-2. These results suggest that TNF-α, TNF-γ, and c-fos are responsible for radiation induced cell death in cervical SCC. (author)

An ultrastructural study of the interaction of human eosinophils with respiratory syncytial virus

NARCIS (Netherlands)

Kimpen, JLL; Garofalo, R; Welliver, RC; Fujihara, K; Ogra, PL

It was shown previously that eosinophils are activated in vivo and in vitro by respiratory syncytial virus (RSV) (Garofalo et al., J Pediatr 1992: 120: 28-32; Kimpen et al., Pediatr Res 1992: 32: 160-4). For study of the interaction of eosinophils and RSV on the ultrastructural level, normodense

Ultrastructure of spermiogenesis and mature spermatozoon of Breviscolex orientalis (Cestoda: Caryophyllidea)

Czech Academy of Sciences Publication Activity Database

Yoneva, Aneta; Levron, Céline; Oros, M.; Orosová, M.; Scholz, Tomáš

2011-01-01

Roč. 108, č. 4 (2011), 997-1005 ISSN 0932-0113 R&D Projects: GA ČR GA524/08/0885; GA ČR GAP506/10/1994; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : GLARIDACRIS-CATOSTOMI COOPER * WENYONIA-VIRILIS WOODLAND * SPERMATOLOGICAL CHARACTERS * SPERM ULTRASTRUCTURE * SPERMATOGENESIS * EUTETRARHYNCHIDAE Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.149, year: 2011

Effects of amino acids and vitamins on the ultrastructure of the hypothalamus and neurotransmitter in exhausted rats

Directory of Open Access Journals (Sweden)

Jian-wei CHEN

2012-01-01

Full Text Available Objective  To investigate the effects of amino acids and vitamins on the ultrastructure of the hypothalamus and neurotransmitter in exhausted rats. Methods  After adaptive swimming, 36 male SD rats were randomly divided into three groups, namely, capsule, control, and granules, with 12 rats in each group. Rats in 3 groups were given respectively amino acids capsule (8 kinds of essential amino acids and 11 kinds of vitamins were contained, normal drinking water, or amino acid-fructose beverage (2.5ml/100g, 2 times per day by gavage for 14 days. Exhaustion of rats was produced by non-loading swimming. The duration of the experiment lasted 14 days. After the last exhaustive swimming, the hypothalamus of the rats was removed for the observation of its ultrastructure under electron microscope. The contents of 5-hydroxytryptamine (5-HT, 5-hydroxyindole acetic acid (5HIAA, hydroxyphenyl acetic acid (HOPAC, and γ-aminobutyric acid (GABA in the hypothalamus were measured with high performance liquid chromatography (HPLC-ECD. Results  The mitochondrial structure in the brain cells of the capsule and granules groups were basically intact. On the other hand, the cells in the control group swelled and degenerated. Different degrees of swelling could be seen in the mitochondria. In addition, obvious morphological changes of the ultrastructure were observed under electron microscopy. Dissolution and rupture of the mitochondrial membrane and cristae were noted, even with the whole mitochondria disrupted and vacuolated. The contents of 5-HT, 5-HTAA, HOPAC, and GABA in the hypothalamus of rats in the capsule and the granules groups were significantly lower than those in the control group (PConclusion  Amino acids and vitamins compound can increase the resistance of the nerve center to fatigue by alleviating pathological changes of ultrastructure and changes in neurotransmitter levels of the hypothalamus.

Phloem Ultrastructure and Pressure Flow: Sieve-Element-Occlusion-Related Agglomerations Do Not Affect Translocation

DEFF Research Database (Denmark)

Froelich, Daniel R.; Mullendore, Daniel L.; Jensen, Kåre Hartvig

2011-01-01

Since the first ultrastructural investigations of sieve tubes in the early 1960s, their structure has been a matter of debate. Because sieve tube structure defines frictional interactions in the tube system, the presence of P protein obstructions shown in many transmission electron micrographs le...

Ultrastructure of the spermatozoon of the diphyllobothriidean cestode Cephalochlamys namaquensis (Cohn, 1906)

Czech Academy of Sciences Publication Activity Database

Bruňanská, M.; Matey, V.; Nebesářová, Jana

2012-01-01

Roč. 111, č. 3 (2012), s. 1037-1043 ISSN 0932-0113 Institutional support: RVO:60077344 Keywords : GLARIDACRIS-CATOSTOMI COOPER * WENYONIA-VIRILIS WOODLAND * SPERMATOLOGICAL CHARACTERS * MATURE SPERMATOZOON * ALAPTERURUS-ELECTRICUS * SPERM ULTRASTRUCTURE * CRASSUM BLOCH * SPERMIOGENESIS * PARASITE * SPERMATOGENESIS Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.852, year: 2012 http://link.springer.com/article/10.1007%2Fs00436-012-2928-4

An ultrastructural comparison of the attachment sites between Gregarina steini and Cryptosporidium muris

Czech Academy of Sciences Publication Activity Database

Valigurová, A.; Hofmannová, L.; Koudela, Břetislav; Vávra, Jiří

2007-01-01

Roč. 54, č. 6 (2007), s. 495-510 ISSN 1066-5234 R&D Projects: GA ČR GD524/03/H133 Institutional research plan: CEZ:AV0Z60220518 Keywords : Apicomplexa * gregarine * Cryptosporidium * feeder organelle * epimerite * parasites * ultrastructure Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.525, year: 2007

Comparative Ultrastructure of Langerhans-Like Cells in Spleens of Ray-Finned Fishes (Actinopterygii)

Czech Academy of Sciences Publication Activity Database

Lovy, J.; Wright, G. M.; Speare, D. J.; Tyml, Tomáš; Dyková, Iva

2010-01-01

Roč. 271, č. 10 (2010), s. 1229-1239 ISSN 0362-2525 R&D Projects: GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : fish * cyprinidae * halibut * dendritic cells * Langerhans cell * Birbeck granules * ultrastructure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.773, year: 2010

Formation of tight junctions between neighboring podocytes is an early ultrastructural feature in experimental crescentic glomerulonephritis

Directory of Open Access Journals (Sweden)

Succar L

2016-11-01

Full Text Available Lena Succar,1 Ross A Boadle,2 David C Harris,1,3 Gopala K Rangan1,3 1Centre for Transplant and Renal Research, The Westmead Institute for Medical Research, The University of Sydney, 2Electron Microscopy Laboratory, Institute of Clinical Pathology and Medical Research, Westmead Hospital, 3Department of Renal Medicine, Westmead Hospital, Western Sydney Local Health District, Westmead, Sydney, NSW, Australia Purpose: In crescentic glomerulonephritis (CGN, the development of cellular bridges between podocytes and parietal epithelial cells (PECs triggers glomerular crescent formation. However, the sequential changes in glomerular ultrastructure in CGN are not well defined. This study investigated the time course of glomerular ultrastructure in experimental CGN. Methods: Transmission electron microscopy (TEM was performed using kidney samples from rats with nephrotoxic serum nephritis (NSN from day 1 to day 14. Morphometric analysis was conducted on randomly selected glomeruli captured on TEM digital images. Results: On day 1 of NSN, there was widespread formation of focal contacts between the cell bodies of neighboring podocytes, and tight junctions were evident at the site of cell-to-cell contact. This was confirmed by the increased expression of the tight junction molecule, zonula occludens-1 (ZO-1, which localized to the points of podocyte cell–cell body contact. On day 2, the interpodocyte distance decreased and the glomerular basement membrane thickness increased. Foot process effacement (FPE was segmental on day 3 and diffuse by day 5, accompanied by the formation of podocyte cellular bridges with Bowman’s capsule, as confirmed by a decrease in podocyte-to-PEC distance. Fibrinoid necrosis and cellular crescents were evident in all glomeruli by days 7 and 14. In vitro, the exposure of podocytes to macrophage-conditioned media altered cellular morphology and caused an intracellular redistribution of ZO-1. Conclusion: The formation of tight

Chromium-induced physio-chemical and ultrastructural changes in four cultivars of Brassica napus L.

Science.gov (United States)

Gill, Rafaqat A; Zang, Lili; Ali, Basharat; Farooq, Muhammad A; Cui, Peng; Yang, Su; Ali, Shafaqat; Zhou, Weijun

2015-02-01

In nature, plants are continuously exposed to several biotic and abiotic stresses. Among these stresses, chromium (Cr) stress is one of the most adverse factors that affects the plant growth, and productivity, and imposes a severe threat for sustainable crop production. In the present study, toxic effects of Cr were studied in hydroponically grown seedlings of four different cultivars of Brassica napus L. viz. ZS 758, Zheda 619, ZY 50 and Zheda 622. The study revealed that elevated Cr concentrations reduced the plant growth rate and biomass as compared to respective controls in all the cultivars and this decline was more obvious in Zheda 622. It was observed that reduction of photosynthetic attributes was more pronounced in Zheda 622 as compared to other cultivars; while, cultivar ZS 758 performed better under Cr-toxicity. Results showed that Cr contents in different parts of seedlings were higher in Zheda 622 as compared to other cultivars and Cr contents were higher in roots than shoots in all the cultivars. Accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA) were induced under different Cr concentrations. Results showed that some of anti-oxidant enzyme activities in leaves and roots were increased under the Cr-toxicity. The electron microscopic study showed that ultrastructural damages in leaf mesophyll and root tip cells were more prominent in Zheda 622 as compared to other cultivars under 400 μM Cr stress. Under 400 μM Cr concentration, changes like broken cell wall, immature nucleus, a number of mitochondria, ruptured thylakoid membranes and large size of vacuole and starch grains were observed in leaf ultrastructures. The damages in root cells were observed in the form of disruption of golgibodies and diffused cell wall under the higher concentration of Cr (400 μM). On the basis of these observations, it was concluded that Zheda 622 was found to be more sensitive as followed by ZY 50, Zheda 619 and ZS 758 under Cr-toxicity. Copyright �

Electroperturbation of human stratum corneum fine structure by high voltage pulses: a freeze-fracture electron microscopy and differential thermal analysis study.

Science.gov (United States)

Jadoul, A; Tanojo, H; Préat, V; Bouwstra, J A; Spies, F; Boddé, H E

1998-08-01

Application of high voltage pulses (HVP) to the skin has been shown to promote the transdermal drug delivery by a mechanism involving skin electroporation. The aim of this study was to detect potential changes in lipid phase and ultrastructure induced in human stratum corneum by various HVP protocols, using differential thermal analysis and freeze-fracture electron microscopy. Due to the time involved between the moment the electric field is switched off and the analysis, only "secondary" phenomena rather than primary events could be observed. A decrease in enthalpies for the phase transitions observed at 70 degrees C and 85 degrees C was detected by differential thermal analysis after HVP treatment. No changes in transition temperature could be seen. The freeze-fracture electron microscopy study revealed a dramatic perturbation of the lamellar ordering of the intercellular lipid after application of HVP. Most of the planes displayed rough surfaces. The lipid lamellae exhibited rounded off steps or a vanished stepwise order. There was no evidence for perturbation of the corneocytes content. In conclusion, the freeze-fracture electron microscopy and differential thermal analysis studies suggest that HVP application induces a general perturbation of the stratum corneum lipid ultrastructure.

Fluoride-associated ultrastructural changes and apoptosis in human renal tubule: a pilot study.

Science.gov (United States)

Quadri, J A; Sarwar, S; Sinha, A; Kalaivani, M; Dinda, A K; Bagga, A; Roy, T S; Das, T K; Shariff, A

2018-01-01

The susceptibility of the kidneys to fluoride toxicity can largely be attributed to its anatomy and function. As the filtrate moves along the complex tubular structure of each nephron, it is concentrated in the proximal and distal tubules and collecting duct. It has been frequently observed that the children suffering from renal impairments also have some symptoms of dental and skeletal fluorosis. The findings suggest that fluoride somehow interferes with renal anatomy and physiology, which may lead to renal pathogenesis. The aim of this study was to evaluate the fluoride-associated nephrotoxicity. A total of 156 patients with childhood nephrotic syndrome were screened and it was observed that 32 of them had significantly high levels ( p ≤ 0.05) of fluoride in urine (4.01 ± 1.83 ppm) and serum (0.1 ± 0.013 ppm). On the basis of urinary fluoride concentration, patients were divided into two groups, namely group 1 (G-1) ( n = 32) containing normal urine fluoride (0.61 ± 0.17 ppm) and group 2 (G-2) ( n = 32) having high urine fluoride concentration (4.01 ± 1.83 ppm). Age-matched healthy subjects ( n = 33) having normal levels of urinary fluoride (0.56 ± 0.15 ppm) were included in the study as control (group 0 (G-0)). Kidney biopsies were taken from G-1 and G-2 only, who were subjected to ultrastructural (transmission electron microscopy) and apoptotic (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling) analysis. Various subcellular ultrastructural changes including nuclear disintegration, chromosome condensation, cytoplasmic ground substance lysis, and endoplasmic reticulum blebbing were observed. Increased levels of apoptosis were observed in high fluoride group (G-2) compared to normal fluoride group (G-1). Various degrees of fluoride-associated damages to the architecture of tubular epithelia, such as cell swelling and lysis, cytoplasmic vacuolation, nuclear condensation, apoptosis, and necrosis, were observed.

Effects of Streptococcus sanguinis Bacteriocin on Cell Surface Hydrophobicity, Membrane Permeability, and Ultrastructure of Candida Thallus

Directory of Open Access Journals (Sweden)

Shengli Ma

2015-01-01

Full Text Available Candida albicans (C.a and Candida tropicalis (C.t were treated with Streptococcus sanguinis bacteriocin (S.s bacteriocin, respectively; the bacteriostatic dynamics of S.s bacteriocin, their effects on cell surface hydrophobicity, leakage of inorganic phosphorus and macromolecular substance, cytosolic calcium concentration, and ultrastructure changes of Candida thallus were detected and analyzed. The results showed that inhibitory effect of S.s bacteriocin on C.a and C.t reached peak level at 24 h, the cell-surface hydrophobicity decreased significantly (P < 0.05 after S.s bacteriocin treatment, and there was leakage of cytoplasmic inorganic phosphorus and macromolecular substance from C.a and C.t; cytosolic calcium concentration decreased greatly. After 24 h treatment by S.s bacteriocin, depressive deformity and defect could be found in the cell surface of C.a and C.t; the thallus displayed irregular forms: C.a was shrunken, there was unclear margins abutting upon cell wall and cell membrane, nucleus disappeared, and cytoplasm was inhomogeneous; likewise, C.t was first plasmolysis, and then the cytoplasm was shrunk, the ultrastructure of cell wall and cell membrane was continuously damaged, and the nucleus was karyolysis. It was illustrated that S.s bacteriocin had similar antifungal effect on C.a and C.t; their cell surface hydrophobicity, membrane permeability, and ultrastructure were changed significantly on exposure to S.s bacteriocin.

Biochemical and Ultrastructural Cardiac Changes Induced by High-Fat Diet in Female and Male Prepubertal Rabbits

Directory of Open Access Journals (Sweden)

Dina Sibouakaz

2018-01-01

Full Text Available Early weight gain induced by high-fat diet has been identified as a predictor for cardiac disease, one of the most serious public health problems. Our goal is to study the influence of a HFD on biochemical, oxidant stress parameters, and the cardiac ultrastructure in both male and female prepubertal models. Experiments were carried on 24 prepubertal New Zealand white rabbits, randomly assigned to male and female control (MC and FC, resp. or HFD (MHFD and FHFD, resp. groups (n=6 for 3 months. Body and heart weights and some biochemical and oxidative stress parameters such as lipids, calcium, CKMB, MDA, uric acid, ascorbic acid, and AOA are evaluated in plasma and the left ventricle. Under HFD effect, plasma parameters, such as lipids (TL, PL, and LDL-C, MDA, and CK-MB, increase more significantly in male than in female groups, when AA decreases. Some cardiac parameters such as TG and UA increase, when AA and AOA decrease; these variations are more significant in FHFD. In both male and female rabbits, HFD caused changes in heart ultrastructure, junctional complexes, mitochondria size and form, and so on. Early HFD feeding induced overweight, oxidative stress, and metabolic alterations in plasma and the heart of prepubertal rabbits, whereas lipotoxicity has especially a negative impact on male plasma but affects more the female heart ultrastructure.

Ultrastructural changes produced in Ehrlich ascites carcinoma cells by ultraviolet-visible radiation in the presence of melanins

Energy Technology Data Exchange (ETDEWEB)

Lea, P.J.; Pawlowski, A.; Persad, S.D.; Menon, I.A.; Haberman, H.F.

1988-01-01

Irradiation of Ehrlich ascites carcinoma (EAC) cells in the presence of pheomelanin, i.e., red hair melanin (RHM), has been reported to produce extensive cell lysis. Irradiation in the presence of eumelanin, i.e., black hair melanin (BHM), or irradiation in the absence of either type of melanin did not produce this effect. We observed that RHM particles penetrated the cell membrane without apparent structural damage to the cell or the cell membrane. Irradiation of the cells in the absence of melanin did not produce any changes in the ultrastructure of the cells. Incubation of the cells in the dark in the presence of RHM produced only minor structural, mainly cytoplasmic changes. Irradiation of the cells in the presence of RHM produced extensive ultrastructural changes prior to complete cell lysis; these changes were more severe than the effects of incubation of the cells in the dark in the presence of RHM. When the cells incubated in the dark or irradiated in the presence of latex particles or either one of the eumelanins particles, viz. BHM or synthetic dopa melanin, these particles did not penetrate into the cells or produce any ultrastructural changes. These particles were in fact not even ingested by the cells.

Effects of different fixation and freeze substitution methods on the ultrastructural preservation of ZYMV-infected Cucurbita pepo (L.) leaves.

Science.gov (United States)

Zechmann, Bernd; Müller, Maria; Zellnig, Günther

2005-08-01

Different fixation protocols [chemical fixation, plunge and high pressure freezing (HPF)] were used to study the effects of Zucchini yellow mosaic virus (ZYMV) disease on the ultrastructure of adult leaves of Styrian oil pumpkin plants (Cucurbita pepo L. subsp. pepo var. styriaca Greb.) with the transmission electron microscope. Additionally, different media were tested for freeze substitution (FS) to evaluate differences in the ultrastructural preservation of cryofixed plant leaf cells. FS was either performed in (i) 2% osmium tetroxide in anhydrous acetone containing 0.2% uranyl acetate, (ii) 0.01% safranin in anhydrous acetone, (iii) 0.5% glutaraldehyde in anhydrous acetone or (iv) anhydrous acetone. No ultrastructural differences were found in well-preserved cells of plunge and high pressure frozen samples. Cryofixed cells showed a finer granulated cytosol and smoother membranes, than what was found in chemically fixed samples. HPF led in comparison to plunge frozen plant material to an excellent preservation of vascular bundle cells. The use of FS-media such as anhydrous acetone, 0.01% safranin and 0.5% glutaraldehyde led to low membrane contrast and did not preserve the inner fine structures of mitochondria. Additionally, the use of 0.5% glutaraldehyde caused the cytosol to be fuzzy and partly loosened. ZYMV-induced ultrastructural alterations like cylindrical inclusions and dilated ER-cisternae did not differ between chemically fixed and cryofixed cells and were found within the cytosol of infected leaf cells and within sieve tube elements. The results demonstrate specific structural differences depending on the FS-medium used, which has to be considered for investigations of selected cell structures.

Ultrastructural Alterations in Lepocinclis acus (Euglenophyta Induced by Medium with High Organic Matter Content

Directory of Open Access Journals (Sweden)

Visitación T. Conforti

2017-11-01

Full Text Available Ultrastructural changes induced by exposure to excess of organic matter were studied in Lepocinclis acus (ex Euglena acus. The cells isolated from the Matanza River, Buenos Aires, Argentina, were grown in soil water medium (SWM. When transferred to medium enriched with Bacteriological Peptone OXOID®, marked body deformation and a significant shortening and widening of the cells was observed. These changes were unexpected in a species with quite rigid cells, a condition previously shown in studies of the pellicle fine structure. Transmission electron microscopy observations suggest that cellular deformation might be facilitated by an increase in strip number, whereas in the original strips normal ultrastructure was maintained. An increase in number and volume of paramylon grains and vacuoles, as well as the presence of membrane whorls in vacuoles was observed. The fine structure of organisms grown in medium with and without organic matter enrichment was compared, and the systematic and ecological importance of morphological changes triggered by cell deformation was discussed.

Age-related ultrastructural and monoamine oxidase changes in the rat optic nerve.

Science.gov (United States)

Taurone, S; Ripandelli, G; Minni, A; Lattanzi, R; Miglietta, S; Pepe, N; Fumagalli, L; Micera, A; Pastore, F S; Artico, M

2016-01-01

The aim of this paper is to study the morphology and the distribution of the monoamine oxidase enzymatic system in the optic nerve of 4 month-old Wistar (young) and 28 month-old Wistar (old) rats. The optic nerve was harvested from 20 young and old rats. The segment of optic nerve was divided longitudinally into two pieces, each 0.1 mm in length. The first piece was used for transmission electron microscopy. The second piece was stained with histochemical reaction for monoamine oxidase. The agerelated changes in the optic nerve of rats include micro-anatomical details, ultrastructure and monoamine oxidase histochemical staining. A strong decrease of the thin nerve fibers and a swelling of the thick ones can be observed in optic nerve fibers of old rats. Increased monoamine oxidase histochemical staining of the optic nerve of aged rats is well demonstrated. The increase of meningeal shealth and the decrease of thin nerve fibers of the optic nerve in old rats are well documented. Morphological, ultrastructural and histochemical changes observed in optic nerve fibers of the old rats show a close relation with aging.

Effect of Different Forms of Hypokinesia on the Ultrastructure of Limbic, Extrapyramidal and Neocortical Areas of the Rat Brain: Electron Microscopic Study

Science.gov (United States)

Zhvania, Mzia G.; Japaridze, Nadezhda J.; Ksovreli, Mariam G.

The effect of chronic restraint stress and chronic hypokinesia "without stress" on the ultrastructure of central and lateral nuclei of amygdala, CA1 and CA3 area of the hippocampus, cingular cortex, nucleus caudatus and motor cortex of adult male rats were elucidated. In some neurons and synapses of abovementioned regions pathological modifications were revealed. More significant alterations provokes chronic restraint stress. Alterations are mostly concentrated: first—in the nuclei of amygdala, then in the CA1 and CA3 areas. Moderate alterations were observed in cingular cortex and nucleus caudatus. In comparing with it, hypokinesia "without stress" provokes only moderate modifications: predominantly in the nucleus caudatus, in lesser degree—in the hippocampus and amygdalae.

Giardia muris and Giardia duodenalis groups: ultrastructural differences between the trophozoites

OpenAIRE

Sogayar,Maria Inês L.; Gregório,Elisa Aparecida

1989-01-01

Trophozoites of the Giardia muris group from hamsters, domestic rats and mice and of the Giardia duodenalis group from hamsters and domestic rats were examined by transmission electron microscopy. The basic ultrastructure of the trophozoites was similar. Differences were shown in the morphology of the ventrolateral flange of the trophozoites of Giardia muris and Giardia duodenalis groups. Marginal plates are less developed in the species of the Giardia duodenalis group. In this group, the dis...

Ultrastructural Studies on Root Nodules of Pithecellobium dulce (Roxb.) Benth. (Fabaceae)

OpenAIRE

Raiha Qadri; A. Mahmood; Mohammad Athar

2007-01-01

Ultrastructural studies were conducted on Pithecellobium dulce (Roxb) Benth. root nodules collected from trees growing under natural conditions. Rhizobial infection on root surface of P. dulce started with curling of root hair. Both curled and straight root hairs were observed. The internal structure of a mature nodule showed an epidermis, cortex, vascular region and a bacteriod region. Vascular bundles were amphicribral. A distinct periderm consisted of sclereid tissue could be observed in t...

Reproductive system and spermatozoa ultrastructure support the phylogenetic proximity of Megadasys and Crasiella (Gastrotricha, Macrodasyida)

NARCIS (Netherlands)

Guidi, L.; Todaro, M.A.; Ferraguti, M.; Balsamo, M.

2014-01-01

The reproductive system and the spermatozoon of Megadasys sterreri from Lanzarote (Canary Islands, Spain) were studied at structural and ultrastructural levels. The species is a simultaneous hermaphrodite with cross-fertilization and shows paired gonads, the male anterior and the female posterior,

A comparative ultrastructural study of pit membranes with plasmodesmata associated thickenings in four angiosperm species

NARCIS (Netherlands)

Rabaey, D.; Lens, F.; Huysmans, S.; Smets, E.; Jansen, S.

2008-01-01

Recent micromorphological observations of angiosperm pit membranes have extended the number and range of taxa with pseudo-tori in tracheary elements. This study investigates at ultrastructural level (TEM) the development of pseudo-tori in the unrelated Malus yunnanensis, Ligustrum vulgare,

The influence of Potato virus Y infection on the ultrastructure of Pssu-ipt transgenic tobacco

Czech Academy of Sciences Publication Activity Database

Schnablová, Renáta; Synková, Helena; Čeřovská, Noemi

2005-01-01

Roč. 166, č. 5 (2005), s. 713-721 ISSN 1058-5893 Institutional research plan: CEZ:AV0Z50380511 Keywords : ultrastructure * viral infection * Potato virus Y-NTN Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.950, year: 2005

Histological and Ultrastructural Effects of Ultrasound-induced Cavitation on Human Skin Adipose Tissue.

Science.gov (United States)

Bani, Daniele; Quattrini Li, Alessandro; Freschi, Giancarlo; Russo, Giulia Lo

2013-09-01

In aesthetic medicine, the most promising techniques for noninvasive body sculpturing purposes are based on ultrasound-induced fat cavitation. Liporeductive ultrasound devices afford clinically relevant subcutaneous fat pad reduction without significant adverse reactions. This study aims at evaluating the histological and ultrastructural changes induced by ultrasound cavitation on the different cell components of human skin. Control and ultrasound-treated ex vivo abdominal full-thickness skin samples and skin biopsies from patients pretreated with or without ultrasound cavitation were studied histologically, morphometrically, and ultrastructurally to evaluate possible changes in adipocyte size and morphology. Adipocyte apoptosis and triglyceride release were also assayed. Clinical evaluation of the effects of 4 weekly ultrasound vs sham treatments was performed by plicometry. Compared with the sham-treated control samples, ultrasound cavitation induced a statistically significant reduction in the size of the adipocytes (P ultrasound treatment caused a significant reduction of abdominal fat. This study further strengthens the current notion that noninvasive transcutaneous ultrasound cavitation is a promising and safe technology for localized reduction of fat and provides experimental evidence for its specific mechanism of action on the adipocytes.

Parainfluenza virus type 5 (PIV-5) morphology revealed by cryo-electron microscopy.

Science.gov (United States)

Terrier, Olivier; Rolland, Jean-Paul; Rosa-Calatrava, Manuel; Lina, Bruno; Thomas, Daniel; Moules, Vincent

2009-06-01

The knowledge of parainfluenza type 5 (PIV-5) virion morphology is essentially based on the observation of negatively stained preparations in conventional transmission electron microscopy (CTEM). In this study, the ultrastructure of frozen-hydrated intact PIV-5 was examined by cryo-electron microscopy (cryo-EM). Cryo-EM revealed a majority of spherical virions (70%), with a lower pleiomorphy than originally observed in CTEM. Phospholipid bilayer thickness, spike length and glycoprotein spikes density were measured. About 2000 glycoprotein spikes were present in an average-sized spherical virion. Altogether, these data depict a more precise view of PIV-5 morphology.

Ultrastructural Observation of the Skin Chloride Cells of Japanese Flounder Paralichthys olivaceus and Turbot Scophthamus maximus Larvae

Institute of Scientific and Technical Information of China (English)

无

2003-01-01

The ultrastructures of skin chloride cells in cultured Japanese flounder and turbot larvae in metamorphosis, which grow in the same feeding conditions, are examined with a transmission electron microscope. These developed skin chloride cells were shaped like flattened ellipsoids and similar in morphology and ultrastructure to typical chloride cells of euryhaline fish gill. They locate in the epidermis and contract with the extra and interior environment through the apical pit and narrow channels. The cytoplasm of cell is full of numerous mitochondria and a ramifying network of tubules. The degeneration of skin chloride cells is observed with development of Japanese flounder larvae. Skin chloride cells of turbot are less developmental than those of Japanese flounder in the same developmental stage.

Ultrastructural study of tissues surrounding replanted teeth and dental implants.

Science.gov (United States)

Shioya, Kazuhiro; Sawada, Takashi; Miake, Yasuo; Inoue, Sadayuki; Yanagisawa, Takaaki

2009-03-01

The aim of this study was to describe the ultrastructure of the dentogingival border at replanted teeth and implants. Wistar rats (8 weeks old) were divided into groups for replantation and implantation experiments. In the former, the upper right first molars were extracted and then immediately replanted. In the latter, pure titanium implants were used. All tissues were fixed, demineralized and embedded in epoxy resin for ultrastructural observations. One week after replantation, the junctional epithelium was lost, and the oral sulcular epithelium covered the enamel surface. The amount of the epithelium increased in 2 weeks, and resembled the junctional epithelium, and the internal basal lamina and hemidesmosomes were formed in 4 weeks. One week after implantation, peri-implant epithelium was formed, and in 2 and 4 weeks, this epithelium with aggregated connective tissue cells were observed. In 8 weeks, the peri-implant epithelium receded, and aligned special cells with surrounding elongated fibroblasts and bundles of collagen fibers appeared to seal the implant interface. In replantation of the tooth, the internal basal lamina remained at the surface of the enamel of the replanted tooth, which is likely to be related to regeneration of the junctional epithelium and the attachment apparatus at the epithelium-tooth interface. Following implantation, a layer of cells with characteristics of connective tissue cells, but no junctional epithelium and attachment apparatus, was formed to seal the site of the implant.

A histomorphologic and ultrastructural study of the malignant tumours of the renal pelvis.

Directory of Open Access Journals (Sweden)

Tyagi N

1993-10-01

Full Text Available The study was carried at two different centres. Only 9 cases of primary malignant tumours of the renal pelvis could be collected during the period of 7 years (1984-1990. Renal pelvis malignancies constituted 0.21% of all the malignancies and 12.16% of all the malignant growths of the kidney (9 out of 74 cases. The age of these patients ranged from 24 to 70 years; the mean being 41.7 years. Male/female ratio was 8:1. Common triad of complaints (pain, haematuria and lump was noticed in 22.2% of patients. Individually they were noticed in 77.8%, 66.7% and 44.4% of patients respectively. Transitional cell carcinoma was the commonest, seen in 7 patients (77.8% whereas squamous cell carcinoma and adenocarcinoma were noticed in one patient (11.1% each. Hydronephrosis, chronic pyelonephritis and nephrolithiasis were noticed in 66.7%, 44.4% and 22.2% of patients respectively. Ultrastructural study of urothelial tumours revealed tumour cells in various stages of differentiation with loss of intercellular junctions and dense collection of rough endopasmic reticulum fibrils around the nucleus.

Effect of the Insecticide Dinotefuran on the Ultrastructure of the Flight Muscle of Female Sogatella furcifera (Hemiptera: Delphacidae).

Science.gov (United States)

Liu, M G; Jiang, C X; Mao, M; Liu, C; Li, Q; Wang, X G; Yang, Q F; Wang, H J

2017-04-01

Sogatella furcifera Horváth (Hemiptera: Delphacidae), is a major migratory pest of rice crops in Asia. The ultrastructure of the flight muscle directly affects the flight ability of insects. The ultrastructure of the flight muscle of some insects can be affected by insecticides. However, the ultrastructure of the flight muscle of S. furcifera and the effect of insecticides on the flight muscle of S. furcifera are not well understood. The present study was conducted to determine the effect of the insecticide dinotefuran on the ultrastructure of the flight muscle of S. furcifera females. In this study, the cross-sectional area and the diameter of the myofibril cross-sections of dinotefuran-treated S. furcifera females increased with the number of days after emergence (DAE), and they were higher than in untreated females. The sarcomere length of myofibrils increased with the number of DAE, and it differed from that of the untreated females. On the first day after emergence, the higher the concentration of dinotefuran, the smaller was the extent of decrease. On the third day after emergence, the higher the concentration of dinotefuran, the larger was the extent of enhancement. For the percentage of mitochondria, those of LC10 and LC20 dinotefuran-treated S. furcifera females increased with the number of DAE and were higher than in untreated females. LC10 dinotefuran-treated S. furcifera females exhibited the largest increase. Thus, our results suggest that the flight ability of S. furcifera increased with time. Some concentrations of dinotefuran can enhance the flight capacity of S. furcifera. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Phytohemagglutinin improves the development and ultrastructure of in vitro-cultured goat (Capra hircus) preantral follicles

International Nuclear Information System (INIS)

Cunha, E.V.; Costa, J.J.N.; Rossi, R.O.D.S.; Silva, A.W.B.; Passos, J.R.S.; Portela, A.M.L.R.; Pereira, D.C.S.T.; Donato, M.A.M.; Campello, C.C.; Saraiva, M.V.A.; Peixoto, C.A.; Silva, J.R.V.; Santos, R.P.

2013-01-01

The objective this study was to determine the effect of phytohemagglutinin (PHA) on survival, growth and gene expression in caprine secondary follicles cultured in vitro. Secondary follicles (∼0.2 mm) were isolated from the cortex of caprine ovaries and cultured individually for 6 days in α-MEM + supplemented with PHA (0, 1, 10, 50, 100, or 200 µg/mL). After 6 days of culture, follicle diameter and survival, antrum formation, ultrastructure and expression of mRNA for FSH receptors (FSH-R), proliferating cell nuclear antigen (PCNA), and neuronal nitric oxide synthase were determined. All treatments maintained follicular survival [α-MEM + (94.59%); 1 µg/mL PHA (96.43%); 10 µg/mL PHA (84.85%); 50 µg/mL PHA (85.29%); 100 µg/mL PHA (88.57%), and 200 µg/mL PHA (87.50)], but the presence of 10 µg/mL PHA in the culture medium increased the antrum formation rate (21.21%) when compared with control (5.41%, P < 0.05) and ensured the maintenance of oocyte and granulosa cell ultrastructures after 6 days of culture. The expression of mRNA for FSH-R (2.7 ± 0.1) and PCNA (4.4 ± 0.2) was also significantly increased in follicles cultured with 10 µg/mL PHA in relation to those cultured in α-MEM + (1.0 ± 0.1). In conclusion, supplementation of culture medium with 10 µg/mL PHA maintains the follicular viability and ultrastructure, and promotes the formation of antral cavity after 6 days of culture in vitro

Ultrastructural studies of synthetic apatite crystals.

Science.gov (United States)

Arends, J; Jongebloed, W L

1979-03-01

In this paper a survey is given of some ultrastructural properties of synthetic hydroxyapatite. The preparation method by which single crystals with a length in the range of 0.1-3.0mm and a defined purity and stoïchiometry can be produced is given. Two groups of materials are considered in detail: carbonate-rich (greater than 0.1% CO3) and low-carbonate hydroxyapatites. The experiments on carbonate-rich material, being the most interesting from a biological point of view, show that acids attack at an active site in the hexagonal basal-plane of the crystals. Later on the crystals dissolve in the center of the crystal parallel to the c-axis forming tube-like structures. The active site can be protected from dissolution if the crystals are pretreated by EHDP or MFP. A comparison with lattice defect theory shows that most likely dislocations of the "hollow-core" type are responsible for the preferential dissolution.

Solar assisted alkali pretreatment of garden biomass: Effects on lignocellulose degradation, enzymatic hydrolysis, crystallinity and ultra-structural changes in lignocellulose

International Nuclear Information System (INIS)

Gabhane, Jagdish; William, S.P.M. Prince; Vaidya, Atul N.; Das, Sera; Wate, Satish R.

2015-01-01

Highlights: • SAAP is an efficient and economic means of pretreatment. • SAAP was found to be efficient in lignin and hemicellulose removal. • SAAP enhanced the enzymatic hydrolysis. • FTIR, XRD and SEM provided vivid understanding about the mode of action of SAAP. • Mass balance closer of 98% for pretreated GB confirmed the reliability of SAAP. - Abstract: A comprehensive study was carried out to assess the effectiveness of solar assisted alkali pretreatment (SAAP) on garden biomass (GB). The pretreatment efficiency was assessed based on lignocellulose degradation, conversion of cellulose into reducing sugars, changes in the ultra-structure and functional groups of lignocellulose and impact on the crystallinity of cellulose, etc. SAAP was found to be efficient for the removal of lignin and hemicellulose that facilitated enzymatic hydrolysis of cellulose. FTIR and XRD studies provided details on the effectiveness of SAAP on lignocellulosic moiety and crystallinity of cellulose. Scanning electron microscopic analysis showed ultra-structural disturbances in the microfibrils of GB as a result of pretreatment. The mass balance closer of 97.87% after pretreatment confirmed the reliability of SAAP pretreatment. Based on the results, it is concluded that SAAP is not only an efficient means of pretreatment but also economical as it involved no energy expenditure for heat generation during pretreatment

Nippotaenia mogurndae Yamaguti et Myiata, 1940 (Cestoda, Nippotaeniidea): first data on spermiogenesis and sperm ultrastructure

Czech Academy of Sciences Publication Activity Database

Bruňanská, M.; Bílý, Tomáš; Nebesářová, Jana

2015-01-01

Roč. 114, č. 4 (2015), s. 1443-1453 ISSN 0932-0113 R&D Projects: GA TA ČR(CZ) TE01020118 Institutional support: RVO:60077344 Keywords : Nippotaeniidea * Nippotaeniamogurndae * spermiogenesis * spermatozoon * ultrastructure Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 2.027, year: 2015

The subacute damage of the dorsal root ganglion induced by collagenase in rats: a study on the ultrastructure of neurons

International Nuclear Information System (INIS)

Li Heping; Zhuang Wenquan; Yang Jianyong; Chen Wei

2005-01-01

Objective: To study the effects of collagenase on the ultrastructure of dorsal root ganglion (DRG) in rats. The safety of collagenase on nerve tissue was investigated. Additionally, the safety of percutaneous collagenase chemonucleolysis (PCCN) on nerve tissue was evaluated. Methods: In total 27 male, healthy SD rats were enrolled. All rats were randomized into 3 groups: normal group (9 rats), subacute damage of collagenase group (9 rats), subacute intervention-analogue group (9 rats). The left L5 DRG was exposed in each rat. One milliliter of the collagenase solution (300 units) was carefully applied to the exposed DRG in collagenase group, and one milliliter of the isotonic saline was applied to the exposed DRG in intervention-analogue group. The morphology of the DRG under electron microscope were analyzed 7-9 days after the procedures. Results: The types, number, and morphology of cells; the membrane of neutrons; the nerve fibers and blood vessels in DRG had not been changed in all groups observed under optic microscope. The difference of the ultrastructure of neutrons in DRG among the normal groups, intervention-analogue group and collagenase group was significant: 1) The eccentric nucleolus were revealed; 2) Swelling mitochondria and absence of mitochondria crests and vesicles. Cytoclasis and apoptosis of neutrons had not been observed under electron microscope. Conclusion: The collagenase used in PCCN dose have a certain damage to the neutreons in DRG. In the procedure of PCCN, the volume and dosage of collagenase should be carefully selected and the intervention should be precisely performed by experienced hands. (authors)

Fructose-Drinking Water Induced Nonalcoholic Fatty Liver Disease and Ultrastructural Alteration of Hepatocyte Mitochondria in Male Wistar Rat

Directory of Open Access Journals (Sweden)

Norshalizah Mamikutty

2015-01-01

Full Text Available Background. Nonalcoholic fatty liver disease (NAFLD is one of the complications of the metabolic syndrome. It encompasses a wide range of disease spectrum from simple steatosis to liver cirrhosis. Structural alteration of hepatic mitochondria might be involved in the pathogenesis of NAFLD. Aims. In the present study, we used a newly established model of fructose-induced metabolic syndrome in male Wistar rats in order to investigate the ultrastructural changes in hepatic mitochondria that occur with fructose consumption and their association with NAFLD pathogenesis. Methods. The concentration of fructose-drinking water (FDW used in this study was 20%. Six male Wistar rats were supplemented with FDW 20% for eight weeks. Body composition and metabolic parameters were measured before and after 8 weeks of FDW 20%. Histomorphology of the liver was evaluated and ultrastructural changes of mitochondria were assessed with transmission electron micrograph. Results. After 8 weeks of fructose consumption, the animals developed several features of the metabolic syndrome. Moreover, fructose consumption led to the development of macrovesicular hepatic steatosis and mitochondrial ultrastructural changes, such as increase in mitochondrial size, disruption of the cristae, and reduction of matrix density. Conclusion. We conclude that in male Wistar rat 8-week consumption of FDW 20% leads to NAFLD likely via mitochondrial structural alteration.

[Quantitative changes in the ultrastructure of myocardial cells in Japanese quail during hypergravity, hypodynamia and space flight].

Science.gov (United States)

Bózner, A; Boda, K; Dostál, J; Matĕjková, Z; Devecka, V

1993-03-01

The experimental work aimed at the quantitative ultrastructure of the myocardial cells of the Japanese quail Coturnix coturnix japonica during hypergravitation, hypodynamism and space flight in a Soviet satellite. For the determination of quantitative changes of the myocardial ultrastructure a morphometrical method was used with parameters like the number of mitochondria, average mitochondrial size, relative mitochondrial volume, deficiency of cristae and relative volume of myofibrils. The quails were observed in 3 groups. The absolute control consisted of quails living in normal Earth conditions, in the laboratory group the quails were exposed to conditions of hypergravitation and hypodynamism in a specially constructed centrifuge, and in the flying group the quails were exposed to space flight in a Soviet orbital station MIR. In the group of absolute controls no pathological changes of the myocardial ultrastructure were found. In the flying group there were no significant changes, with the exception of decreased relative volume of myofibrils, which however agrees with the findings on symptoms corresponding to human and animal heart weakness during space flights. In the laboratory group, pathological changes were observed in each of the fractions. The most significant pathological findings were found in the group controls in the center and in hypergravitation combined with hypodynamism. It can be concluded that the laboratories can simulate conditions induced by the start and flight of space ships. (Fig. 2, Ref, 8.)

Ultrastructure of cuticle deposited inPlodia interpunctella wing discs after variousβ-ecdysone treatments in vitro.

Science.gov (United States)

Dutkowski, A B; Oberlander, H; Leach, C E

1977-06-01

Wing discs of the Indian meal moth may be cultured for extended periods in vitro. The discs produced a tanned cuticle after continuous incubation with β-ecdysone in medium conditioned with fat body or after a 24-h pulse incubation with β-ecdysone in plain medium. We investigated the ultrastructure of the cuticle deposited by such discs. We found that the treatment that produced the most complete cuticle in vitro was the 24-h pulse of hormone. We observed that cuticle formation in vitro was not "all-or-none." Depending on culture conditions, discs produced cuticulin only, complete epicuticle, epicuticle plus diffuse endocuticle, epicuticle plus lamellate endocuticle, or even multiple layers of cuticle. The ultrastructural evidence suggests that continuous incubation with β-ecdysone in plain medium does not always inhibit cuticle formationper se, but does prevent tanning of the partially formed cuticle.

[THE EFFECT OF ACID RAIN ON ULTRASTRUCTURE AND FUNCTIONAL PARAMETERS OF PHOTOSYNTHETIC APPARATUS OF PEA LEAVES].

Science.gov (United States)

Polishchuk, A V; Vodka, M V; Belyavskaya, N A; Khomochkin, A P; Zolotareva, E K

2016-01-01

The effects of simulated acid rain (SAR) on the ultrastructure and functional parameters of the photosynthetic apparatus were studied using 14-day-old pea leaves as test system. Pea plants were sprayed with an aqueous solution containing NaNO₃(0.2 mM) and Na₂SO₄(0.2 mM) (pH 5.6, a control variant), or with the same solution, which was acidified to pH 2.5 (acid variant). Functional characteristics were determined by chlorophyll fluorescence analysis. Acid rain application caused reduction in the efficiency of the photosynthetic electron transport by 25%, which was accompanied by an increase by 85% in the quantum yield of thermal dissipation of excess light quanta. Ultrastructural changes in chloroplast were registered by transmission electron microscopy (TEM) after two days of the SAR-treatment of pea leaves. In this case, the changes in the structure of grana, heterogeneity of thylakoids packaging in granum, namely, the increase of intra-thylakoid gaps and thickness of granal thylakoids compared to the control were found. The migration of protein complexes in thylakoid membranes of chloroplasts isolated from leaves treated with SAR was suppressed. It was shown also that carbonic anhydrase activity was inhibited in chloroplast preparations isolated from SAR-treated pea leaves. We proposed a hypothesis on the possible inactivation of thylakoid carbonic anhydrase under SAR and its involvement in the inhibition of photochemical activity of chloroplasts. The data obtained allows to suggest that acid rains negatively affect the photosynthetic apparatus disrupting the membrane system of chloroplast.

Histopathological and Ultrastructural Studies of Liver Tissue from TCDD-Exposed Beach Mice (Peromyscus polionotus).

Science.gov (United States)

1980-03-01

TQuantitative ultrastructural studies were conducted on liver tissue f ran beach Lj mice, Per~ ascus polionotus, exposed to the toxin 2,3, 7f8...weights per se was not attempted since the ages of the beach mice were not known and the animals could only be classified by sex and treatment. The

[ULTRASTRUCTURE OF PARENCHYMA IN THE SYNCYTIAL DIGESTIVE SYSTEM IN TURBELLARIA Convoluta convoluta (Acoela].

Science.gov (United States)

Gazizova, G R; Zabotin, Ya I; Golubev, A I

2015-01-01

The paper presents data on the ultrastructure of parenchyma that is involved in the digestion in turbellaria Convoluta convoluta (n = 15). Unusual connections between the nuclear envelope, endoplasmic reticulum and plasma membrane of parenchymal cells were found for the first time, which may indicate the origin of these cell structures. The double trophic role of zooxanthellae in the organism of Convoluta is described.

Ultrastructural, Confocal and Viscoelastic Characteristics of Whole Blood and Plasma After Exposure to Cadmium and Chromium Alone and in Combination: An Ex Vivo Study

Directory of Open Access Journals (Sweden)

Chantelle Venter

2017-10-01

Full Text Available Background/Aims: Heavy metal pollution is increasing in the environment, contaminating water, food and air supplies. This can be linked to many anthropogenic activities. Heavy metals are absorbed through the skin, inhalation and/or orally. Irrespective of the manner of heavy metal entry in the body, the blood circulatory system is potentially the first to be affected following exposure and adverse effects on blood coagulation can lead to associated thrombotic disease. Although the plasma levels and the effects of cadmium (Cd and chromium (Cr on erythrocytes and lymphocytes have been described, the environmental exposure to heavy metals are not limited to a single metal and often involves metal mixtures, with each metal having different rates of absorption, different cellular, tissue, and organ targets. Therefore the aim of this study is to investigate the effects of the heavy metals Cd and Cr alone and whether Cr synergistically increases the effect of Cd on physiological important processes such as blood coagulation. Methods: Human blood was exposed to the heavy metals ex vivo, and thereafter morphological analysis was performed with scanning electron- and confocal laser scanning microscopy (CLSM in conjunction with thromboelastography®. Results: The erythrocytes, platelets and fibrin networks presented with ultrastructural changes, including varied erythrocytes morphologies, activated platelets and significantly thicker fibrin fibres in the metal-exposed groups. CLSM analysis revealed the presence of phosphatidylserine on the outer surface of the membranes of the spherocytic erythrocytes exposed to Cd and Cr alone and in combination. The viscoelastic analysis revealed only a trend that indicates that clots that will form after heavy metal exposure, will likely be fragile and unstable especially for Cd and Cr in combination. Conclusion: This study identified the blood as an important target system of Cd and Cr toxicity.

Observations on the sexual segment of the kidney of snakes with emphasis on ultrastructure in the yellow-bellied sea snake, Pelamis platurus.

Science.gov (United States)

Sever, David M; Rheubert, Justin L; Gautreaux, Jillian; Hill, Toren G; Freeborn, Layla R

2012-05-01

The sexual segment of the kidney (SSK) is an accessory sex structure in male lizards and snakes (Squamata). We describe histology of the SSK in 12 species of snakes, including one from the basal Scolecophidia, Leptotyphlops dulcis, and from the more advanced Alethinophidia, species from the Acrochordidae (Acrochordus granulatus), Homalopsidae (Cerberus rynchops), Uropeltidae (Teretrurus sanguineus), and eight species from the Elapidae, including six species of sea snakes. We also describe the ultrastructure of the SSK of the sea snake, Pelamis platurus. The SSK of L. dulcis does not include the ureter but does include distal convoluted tubules (DCTs) and collecting ducts. In all other snakes examined, the SSK is limited to the DCTs and does not differ in histology by any consistent character. We found apparently mature individuals of several species with inactive SSKs. Hypertrophied SSKs give positive reactions for protein secretions but variable reactions for carbohydrates. Ultrastructure of the SSK of P. platurus reveals nuclei situated medially in the epithelium and mature electron dense secretory vacuoles in other areas of the cytoplasm. Product release is apocrine. Junctional complexes only occur at the luminal border, and intercellular canaliculi become widened and are open basally. No cytologically unique characters occur in the SSK of P. platurus. The ancestral condition of the SSK in squamates is the presence of simple columnar epithelium specialized for secretion of a protein + carbohydrate product that matures and is released seasonally. Copyright © 2012 Wiley Periodicals, Inc.

Molecular, Biochemical and Ultrastructural Changes Induced by Pb Toxicity in Seedlings of Theobroma cacao L.

Science.gov (United States)

Reis, Graciele Santos Monteiro; de Almeida, Alex-Alan Furtado; de Almeida, Nicolle Moreira; de Castro, Andressa Vieira; Mangabeira, Pedro Antonio Oliveira; Pirovani, Carlos Priminho

2015-01-01

Pb is a metal which is highly toxic to plants and animals, including humans. High concentrations of Pb have been observed in beans of T. cacao, as well as in its products. In this work, we evaluated the molecular, biochemical, and ultrastructural alterations in mature leaves and primary roots of seedlings of two progenies of T. cacao, obtained from seed germination in different concentrations of Pb (0, 0.05, 0.1, 0.2, 0.4, 0.8 g L(-1)), in the form of Pb(NO3)2. The progenies resulted from self-fertilization of Catongo and a cross of CCN-10 x SCA-6. The Pb, supplied via seminal, caused alterations in the ultrastructures of the mesophyll cells and in the amount of starch grains in the chloroplasts. The dosage of substances reactive to thiobarbituric acid showed that Pb induced lipid peroxidation. The activity of guaiacol peroxidases and the expression of genes associated to synthetase of phytochelatin, SODcyt and PER increased in response to Pb. In addition, there was alteration in the expression of stress-related proteins. The progeny of CCN-10 x SCA-6 was more tolerant to Pb stress when compared to Catongo, since: (i) it accumulated more Pb in the roots, preventing its translocation to the shoot; (ii) it presented higher activity of peroxidases in the roots, which are enzymes involved in the elimination of excess of reactive oxygen species; and (iii) increased expression of the gene in the phytochelatin biosynthesis route. The results of the proteomic analysis were of paramount importance to differentiate the defense mechanisms used by both progenies of T. cacao.

Histology and ultrastructure of the integumental chromatophores in tokay gecko (Gekko gecko) (Linnaeus, 1758) skin.

Science.gov (United States)

Szydłowski, Paweł; Madej, Jan Paweł; Mazurkiewicz-Kania, Marta

2017-01-01

This paper describes the relationship between the arrangement of dermal chromatophores in tokay gecko ( Gekko gecko ) skin and the formation of wild-type colouration, with emphasis on the ultrastructure of chromatophores. The samples of the tokay gecko skin were collected from wild-type colouration adult specimens. Morphology and distribution of chromatophores was determined by using light microscopy and transmission electron microscopy. The present study revealed that orange/red coloured skin of G. gecko contained erythrophores, which were located under basement membrane, and usually comprised deeper situated iridophores and melanophores which were form single layer with iridophores or were occupying the deepest region of dermis. In orange/red coloured skin, erythrophores were the predominant chromatophores. However in blue areas these cells occurred in small numbers or were not noticed at all. In blue pigmented areas predominated iridophores and melanophores. Iridophores were found just under basement membrane, but this superficial location of iridophores occured only in areas without erythrophores. Distribution of erythrophores, melanophores, and iridophores determines the characteristic blue colour of the tokay gecko skin with orange/red dots on the whole body.

Ultrastructural findings in Hashimoto's thyroiditis and focal lymphocytic thyroiditis with reference to giant cell formation.

Science.gov (United States)

Knecht, H; Hedinger, C E

1982-09-01

Ultrastructural findings in two cases of Hashimoto's disease and two cases of focal lymphocytic thyroiditis are reported. Stimulated thyrocytes, oncocytes and degenerating thyrocytes were observed in all cases. Multinucleated thyrocytes and epithelial pseudogiant cells were identified in Hashimoto's disease only. Infiltrating lymphocytes, plasma cells, monocytes and macrophages were present in all cases. The ultrastructure of germinal centres was similar to that seen in lymphatic organs. Giant cells of both intra- and extrafollicular localization were seen in Hashimoto's disease. Most of the giant cells were macrophage-derived. Two different ways of giant cell formation were identified: besides the familiar dissolution of plasma membranes of adjacent macrophages, another mechanism of fusion was observed. At sites of contact, peculiar membrane structures were developed and disintegration of plasma membranes occurred in parts adjacent to these structures. These are not identical to desmosomes and are different from Langerhans' granules. They probably represent special organelles for the initiation of cellular fusion.

Water pollution causes ultrastructural and functional damages in Pellia neesiana (Gottsche) Limpr.

Science.gov (United States)

Basile, Adriana; Sorbo, Sergio; Lentini, Marco; Conte, Barbara; Esposito, Sergio

2017-09-01

The aim of this work is to evaluate the effects of freshwater pollution in the heavily contaminated Sarno River (Campania, South Italy), using Pellia neesiana (Pelliaceae Metzgeriales) in order to propose this liverwort as a potential bioindicator, able to record the effects of water pollution, particularly the one related to metal (loid) contamination. Samples of P. neesiana in nylon bags were disposed floating for one week on the waters of Sarno River in three sites characterised by an increasing pollution. As control, some specimens were cultured in vitro in Cd- and Pb-added media, at the same pollutants' levels as measured in the most polluted site. P. neesiana cell ultrastructure was modified and severe alterations were observed in chloroplasts from samples exposed in the most polluted site, and Cd- and Pb-cultured samples. Concurrently, a strong increase in the occurrence of Heat shock proteins 70 (HSP70) was detected in gametophytes following the pollution gradient. In conclusion, ultrastructural damages can be directly related to HSP 70 occurrence in liverwort tissues, and proportional to the degree of pollution present in the river; thus our study suggests P. neesiana as an affordable bioindicator of freshwaters pollution. Copyright © 2016 Elsevier GmbH. All rights reserved.

Platinum-Based Drugs Differentially Affect the Ultrastructure of Breast Cancer Cell Types

Directory of Open Access Journals (Sweden)

Shadia Al-Bahlani

2017-01-01

Full Text Available Breast cancer (BC is the most common cause of cancer-related death worldwide. Although platinum-based drugs (PBDs are effective anticancer agents, responsive patients eventually become resistant. While resistance of some cancers to PBDs has been explored, the cellular responses of BC cells are not studied yet. Therefore, we aim to assess the differential effects of PBDs on BC ultrastructure. Three representative cells were treated with different concentrations and timing of Cisplatin, Carboplatin, and Oxaliplatin. Changes on cell surface and ultrastructure were detected by scanning (SEM and transmission electron microscope (TEM. In SEM, control cells were semiflattened containing microvilli with extending lamellipodia while treated ones were round with irregular surface and several pores, indicating drug entry. Prolonged treatment resembled distinct apoptotic features such as shrinkage, membrane blebs, and narrowing of lamellipodia with blunt microvilli. TEM detected PBDs’ deposits that scattered among cellular organelles inducing structural distortion, lumen swelling, chromatin condensation, and nuclear fragmentation. Deposits were attracted to fat droplets, explained by drug hydrophobic properties, while later they were located close to cell membrane, suggesting drug efflux. Phagosomes with destructed organelles and deposits were detected as defending mechanism. Understanding BC cells response to PBDs might provide new insight for an effective treatment.

Morphology and ultrastructure of the freshwater rotifer Brachionus bidentatus (Monogononta: Brachionidae) using scanning and transmission electron microscopy.

Science.gov (United States)

Guerrero-Jiménez, Gerardo; Zavala-Padilla, Guadalupe; Silva-Briano, Marcelo; Rico-Martínez, Roberto

2013-12-01

The study of sexual reproductive behavior supported by ultrastructural evidence is important in rotifers to describe differences among potential cryptic species. In this research, the morphology of the rotifer Brachionus bidentatus is described at the ultrastructural level, using electronic microscopy, together with a brief description and discussion of its sexual reproductive behavior. The characteristics of the (a) male, (b) the female, (c) the sexual egg or cyst, (d) the partenogenic egg, (e) the no-fecundated sexual egg (male egg), and (f) the trophi, were described. Another part of this research is dedicated to the ultrastructure of the sex cells of the male rotifer B. bidentatus. Samples were obtained from La Punta pond in Cosio, Aguascalientes, Mexico (22 degrees 08' N - 102 degrees 24' W), and a culture was maintained in the laboratory. Fifty organisms, from different stages of the rotifer Brachionus bidentatus, were fixed in Formol at 4% and then prepared; besides, for the trophi, 25 female rotifer Brachionus bidentatus were prepared for observation in a JEOL 5900 LV scanning electronic microscope. In addition, for the observation of male sex cells, 500 males of Brachionus bidentatus were isolated, fixed and observed in a JEOL 1010 transmission microscope. Females of B. bidentatus in laboratory cultures had a lifespan of five days (mean+one SD = 4.69 +/- 0.48; N=13), and produced 4.5 +/- 3.67 (N=6) parthenogenetic eggs during such lifespan. In the case of non-fertilized sexual eggs, they produced up to 18 eggs (mean+one SD = 13 +/- 4.93; N=7). Sexual females produced a single cyst on average (mean +/- one SD = I +/- 0; N=20). For the sexual cycle, the time of copulation between male and female ranged from 10 to 40 seconds (mean +/- one SD = 17.33 +/- 10.55, N=7). The spermatozoa are composed of a celular body and a flagellum, the size of the body is of 300 nm while the flagellum measures 1 700nm. The rods have a double membrane. Their mean length is almost

Effects of shading on the photosynthetic characteristics and mesophyll cell ultrastructure of summer maize.

Science.gov (United States)

Ren, Baizhao; Cui, Haiyan; Camberato, James J; Dong, Shuting; Liu, Peng; Zhao, Bin; Zhang, Jiwang

2016-08-01

A field experiment was conducted to study the effects of shading on the photosynthetic characteristics and mesophyll cell ultrastructure of two summer maize hybrids Denghai605 (DH605) and Zhengdan958 (ZD958). The ambient sunlight treatment was used as control (CK) and shading treatments (40 % of ambient sunlight) were applied at different growth stages from silking (R1) to physiological maturity (R6) (S1), from the sixth leaf stage (V6) to R1 (S2), and from seeding to R6 (S3), respectively. The net photosynthetic rate (P n) was significantly decreased after shading. The greatest reduction of P n was found at S3 treatment, followed by S1 and S2 treatments. P n of S3 was decreased by 59 and 48 % for DH605, and 39 and 43 % for ZD958 at tasseling and milk-ripe stages, respectively, compared to that of CK. Additionally, leaf area index (LAI) and chlorophyll content decreased after shading. In terms of mesophyll cell ultrastructure, chloroplast configuration of mesophyll cells dispersed, and part of chloroplast swelled and became circular. Meanwhile, the major characteristics of chloroplasts showed poorly developed thylakoid structure at the early growth stage, blurry lamellar structure, loose grana, and a large gap between slices and warping granum. Then, plasmolysis occurred in mesophyll cells and the endomembrane system was destroyed, which resulted in the dissolution of cell membrane, karyotheca, mitochondria, and some membrane structures. The damaged mesophyll cell ultrastructure led to the decrease of photosynthetic capacity, and thus resulted in significant yield reduction by 45, 11, and 84 % in S1, S2, and S3 treatments, respectively, compared to that of CK.

Ultrastructural changes and nestin expression accompanying compensatory renal growth after unilateral nephrectomy in adult rats

Directory of Open Access Journals (Sweden)

Eladl MA

2017-02-01

Full Text Available Mohamed Ahmed Eladl,1,2 Wael M Elsaed,2,3 Hoda Atef,4 Mohamed El-Sherbiny2 1Department of Basic Medical Sciences, University of Sharjah, Sharjah, United Arab Emirates; 2Anatomy and Embryology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt; 3Anatomy and Embryology Department, Faculty of Medicine, Taibah University, Madinah, Saudi Arabia; 4Department of Histology, University of Mansoura, Mansoura, Egypt Background: Several renal disorders affect the glomerular podocytes. Compensatory structural and functional changes have been observed in animals that have undergone unilateral renal ablation. These changes occur as a pliant response to quench the increased functional demand to maintain homeostasis of fluid and solutes. Nestin is an intermediate filament protein present in the glomerular podocytes of the adult kidney and is linked with the maintenance of its foot process structure. Structural changes in the podocytes ultimately restructure the filtration barrier. Very few studies related to the ultrastructural and histopathologic changes of the podocytes are documented. The present study aimed to assess the histopathologic changes at the ultrastructural level in the adapted kidney at different time intervals following unilateral renal ablation in adult rats and its relation with nestin.Methods: Forty-eight rats were divided into four groups (n=12 in each group. The animals of Group A were control naïve rats, while the group B, group C and group D animals underwent left unilateral nephrectomy and the remaining right kidney was removed on days 10, 20 and 30, respectively. Each group included four sham-operated rats, which were sacrificed at the same time as the naïve rats. Each nephrectomized sample was weighed and its sections were subjected to hematoxylin and eosin examination, transmission electron microscopic study as well as immunostaining using the intermediate filament protein nestin.Results: No difference was found

Ultrastructural and some functional changes in tumor cells treated with stabilized iron oxide nanoparticles.

Science.gov (United States)

Yurchenko, O V; Todor, I N; Khayetsky, I K; Tregubova, N A; Lukianova, N Yu; Chekhun, V F

2010-12-01

To study the ultrastructure and some functional indexes of tumor cells treated with stabilized iron nanoparticles in vitro. 3-[4,5dimethylthiazol-2-1]-2,5-diphenyltetrazolium bromide (MTT)-test, electron microscopy, polarography with applying of closed Clark's electrode. It was shown that cultivation of cells with stabilized Fe(3)O(4) leads to intracellular accumulation of ferromagnetic nanoparticles. The most active ferromagnetic uptake by cells has been observed after 24 and 48 h of incubation. The presence of ferromagnetic in cells led to altered mitochondrial structure that caused the decrease of oxygen uptake rate in the cells of all studied lines. Ferromagnetic released from the majority of cells via exocytosis or clasmacytosis after a certain period of time. The number of dead cells or cells with severe damage was moderate, so cytotoxic action of stabilized iron oxide nanoparticles was minimal toward the studied cell lines. the presence of ferromagnetic nanoparticles in culture medium led to alterations in mitochondria ultrastructural organization and decrease of oxygen uptake by mitochondria in sensitive and anticancer-drugs resistant cells.

Structural and ultrastructural studies of the urinary tract of mice inoculated with Lactobacillus fermentum.

Science.gov (United States)

Silva de Ruiz, C; del R Rey, M; Nader-Macías, M E

2003-06-01

To assess, using structural and ultrastructural studies of the urinary tract, the effects of the intraurethral inoculation of lactobacilli (probiotic treatment) as lactobacilli are the predominant micro-organisms of the urogenital tract of humans, monkeys and mice. Previous work showed the protective effect of Lactobacillus fermentum CRL 1058 intraurethrally inoculated against the challenge of uropathogenic Escherichia coli. There was also an effect of oestrogens and antibiotics in the kinetics of colonization of both micro-organisms in mice. In the present study L. fermentum was inoculated with agarose beads (107 colony-forming units) and the number of micro-organisms determined by plating in selective media, giving a high degree of colonization in all the organs studied. The urinary tract organs were processed by histological and electron microscopy techniques standardized in our laboratory. The intraurethral inoculation of lactobacilli produced no adverse effects or significant changes in any of the organs assessed (kidney, ureter, bladder or urethra), when evaluated by histological and ultrastructural techniques. The use of lactobacilli as a probiotic treatment is probably safe.

The Ultrastructure Of Pollinia Of Ten Species Of Orchid In Substribe Aeridinae (ORCHIDACEAE)

International Nuclear Information System (INIS)

Sulistyono; Purbaningsih, Susiani; Pujoarianto, Agus

2000-01-01

Orchid taxonimy lags several decades behind the taxonomy of most other large interisting groups of plants. New methods and techiniques, like scanning and transmission electron microscope are rarely applied in orchid's taxonomy. It would be most benefical to orchid taxonomy if a better understanding of the pollinia could be obtained. The main purpose of this research is to study the ultrastructure pollinia of ten species of Aeridinae (Orchidaceae). The scanning electron microscope (SEM) has been used to study the pollinia of ten species of orchids in the substribe Aeridina. This work shows that the ultrastructure of the pollinias are different. Regarding at the number and the surface of pollinia in one flowe, the ten species of Aeridinae can be devided mto three main group: (1) the first group is the flowe with two pollinia with it surface porate : Ascocentrum miniatum; (2) the second group has the same number of pollinia, but with surface cleft : Phalaenopsis. Ph. amboinensis, Ph.cornu-cervi, Ph. Fuscata, Ph. Venosa, Rhychostylis retusa, Vanda limbota, and Vanda insignis: and the third (3)is the flower with four pollinia, unequel : Kingidium deliciosum

A functional thyrotropin- and growth hormone-secreting pituitary adenoma with a ultrastructurally monomorphic feature: a case study.

Science.gov (United States)

Ozawa, Y; Kameya, T; Kasuga, A; Naritaka, H; Kanda, N; Maruyama, H; Saruta, T

1998-04-01

A 38-yr-old female with a TSH- and GH-secreting pituitary adenoma is described, who had both overt symptoms, hyperthyroidism and acromegaly. Her serum TSH was not suppressed despite high concentrations of free T3 and free T4, and her alpha-subunit/TSH molar ratio was high. Her serum GH was consistently high, and was not suppressed by an oral glucose tolerance test. Preoperative testing revealed that, although the TSH response was impaired, TSH, alpha-subunit and GH were increased by TRH injection, and that these hormones were reduced by bromocriptine or somatostatin analog. Although she did not have hyperprolactinemia, the in vitro culture and immunohistochemical studies revealed that the adenoma cells produced and released PRL, in addition to TSH, alpha-subunit and GH. Immunohistochemical studies showed the presence of GH in the cytoplasm of many adenoma cells. TSH beta-positive adenoma cells were less frequently seen than GH-positive adenoma cells. No cells showed the coexistence of GH and TSH beta, and a few cells were positive for PRL. By electron microscopy, the adenoma was found to be composed of a single cell type resembling thyrotrophs, and did not have any characteristics of somatotrophs. This case was considered to be of interest, because the adenoma was ultrastructurally monomorphous, but immunohistochemically polymorphous.

Comparative studies on intestine ultrastructure of third-stage larvae and adults of Cystidicoloides ephemeridarum (Nematoda, Cystidicolidae)

Czech Academy of Sciences Publication Activity Database

Frantová, Denisa; Moravec, František

2004-01-01

Roč. 94, č. 5 (2004), s. 377-383 ISSN 0932-0113 R&D Projects: GA AV ČR KJB6022305 Institutional research plan: CEZ:AV0Z6022909 Keywords : Nematoda * Cystidicolidae * ultrastructure Subject RIV: EG - Zoology Impact factor: 1.060, year: 2004

Phytohemagglutinin improves the development and ultrastructure of in vitro-cultured goat (Capra hircus) preantral follicles

Energy Technology Data Exchange (ETDEWEB)

Cunha, E.V.; Costa, J.J.N.; Rossi, R.O.D.S.; Silva, A.W.B.; Passos, J.R.S.; Portela, A.M.L.R.; Pereira, D.C.S.T. [Núcleo de Biotecnologia de Sobral, NUBIS, Universidade Federal do Ceará, Sobral, CE (Brazil); Donato, M.A.M. [Laboratório de Ultraestrutura, CPqAM/FIOCRUZ, Universidade Federal de Pernambuco, Recife, PE (Brazil); Campello, C.C. [Laboratório de Manipulação de Oócitos e Folículos Pré-Antrais, Faculdade de Medicina Veterinária, Universidade Estadual do Ceará, Fortaleza, CE (Brazil); Saraiva, M.V.A. [Núcleo de Biotecnologia de Sobral, NUBIS, Universidade Federal do Ceará, Sobral, CE (Brazil); Peixoto, C.A. [Laboratório de Ultraestrutura, CPqAM/FIOCRUZ, Universidade Federal de Pernambuco, Recife, PE (Brazil); Silva, J.R.V.; Santos, R.P. [Núcleo de Biotecnologia de Sobral, NUBIS, Universidade Federal do Ceará, Sobral, CE (Brazil)

2013-03-19

The objective this study was to determine the effect of phytohemagglutinin (PHA) on survival, growth and gene expression in caprine secondary follicles cultured in vitro. Secondary follicles (∼0.2 mm) were isolated from the cortex of caprine ovaries and cultured individually for 6 days in α-MEM{sup +} supplemented with PHA (0, 1, 10, 50, 100, or 200 µg/mL). After 6 days of culture, follicle diameter and survival, antrum formation, ultrastructure and expression of mRNA for FSH receptors (FSH-R), proliferating cell nuclear antigen (PCNA), and neuronal nitric oxide synthase were determined. All treatments maintained follicular survival [α-MEM{sup +} (94.59%); 1 µg/mL PHA (96.43%); 10 µg/mL PHA (84.85%); 50 µg/mL PHA (85.29%); 100 µg/mL PHA (88.57%), and 200 µg/mL PHA (87.50)], but the presence of 10 µg/mL PHA in the culture medium increased the antrum formation rate (21.21%) when compared with control (5.41%, P < 0.05) and ensured the maintenance of oocyte and granulosa cell ultrastructures after 6 days of culture. The expression of mRNA for FSH-R (2.7 ± 0.1) and PCNA (4.4 ± 0.2) was also significantly increased in follicles cultured with 10 µg/mL PHA in relation to those cultured in α-MEM{sup +} (1.0 ± 0.1). In conclusion, supplementation of culture medium with 10 µg/mL PHA maintains the follicular viability and ultrastructure, and promotes the formation of antral cavity after 6 days of culture in vitro.

Spermiogenesis and spermatozoon of the tapeworm Parabothriocephalus gracilis (Bothriocephalidea): Ultrastructural and cytochemical studies

Czech Academy of Sciences Publication Activity Database

Šípková, Lenka; Levron, Céline; Freeman, M.; Scholz, Tomáš

2010-01-01

Roč. 55, č. 1 (2010), s. 58-65 ISSN 1230-2821 R&D Projects: GA ČR GP524/07/P039; GA ČR GA524/08/0885; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Eucestoda * Bothriocephalidea * Parabothriocephalus gracilis * spermiogenesis * spermatozoon * ultrastructure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.144, year: 2010

Molecular and Ultrastructural Mechanisms Underlying Yellow Dwarf Symptom Formation in Wheat after Infection of Barley Yellow Dwarf Virus.

Science.gov (United States)

Rong, Wei; Wang, Xindong; Wang, Xifeng; Massart, Sebastien; Zhang, Zengyan

2018-04-13

Wheat ( Tritium aestivum L.) production is essential for global food security. Infection of barley yellow dwarf virus-GAV (BYDV-GAV) results in wheat showing leaf yellowing and plant dwarfism symptom. To explore the molecular and ultrastructural mechanisms underlying yellow dwarf symptom formation in BYDV-GAV-infected wheat, we investigated the chloroplast ultrastructure via transmission electron microscopy (TEM), examined the contents of the virus, H₂O₂, and chlorophyll in Zhong8601, and studied the comparative transcriptome through microarray analyses in the susceptible wheat line Zhong8601 after virus infection. TEM images indicated that chloroplasts in BYDV-GAV-infected Zhong8601 leaf cells were fragmentized. Where thylakoids were not well developed, starch granules and plastoglobules were rare. Compared with mock-inoculated Zhong8601, chlorophyll content was markedly reduced, but the virus and H₂O₂ contents were significantly higher in BYDV-GAV-infected Zhong8601. The transcriptomic analyses revealed that chlorophyll biosynthesis and chloroplast related transcripts, encoding chlorophyll a/b binding protein, glucose-6-phosphate/phosphate translocator 2, and glutamyl-tRNA reductase 1, were down-regulated in BYDV-GAV-infected Zhong8601. Some phytohormone signaling-related transcripts, including abscisic acid (ABA) signaling factors (phospholipase D alpha 1 and calcineurin B-like protein 9) and nine ethylene response factors, were up-regulated. Additionally, reactive oxygen species (ROS)-related genes were transcriptionally regulated in BYDV-GAV infected Zhong8601, including three up-regulated transcripts encoding germin-like proteins (promoting ROS accumulation) and four down-regulated transcripts encoding peroxides (scavenging ROS). These results clearly suggest that the yellow dwarf symptom formation is mainly attributed to reduced chlorophyll content and fragmentized chloroplasts caused by down-regulation of the chlorophyll and chloroplast biosynthesis

Cadmium-induced functional and ultrastructural alterations in roots of two transgenic cotton cultivars

International Nuclear Information System (INIS)

Daud, M.K.; Sun, Yuqiang; Dawood, M.; Hayat, Y.; Variath, M.T.; Wu Yuxiang; Raziuddin; Mishkat, Ullah; Salahuddin; Najeeb, Ullah; Zhu, Shuijin

2009-01-01

The toxic effect of cadmium (Cd) at increasing concentrations was studied with special attention being given to the root morphological and ultrastructural changes in two transgenic cotton cultivars viz. BR001 and GK30 and their wild relative viz. Coker 312. In comparison to their respective controls, low concentration (10 and 100 μM) of Cd greatly stimulated seed germination, while it was inhibited by highest concentration of Cd (1000 μM) in case of two transgenic cultivars. However, in Coker 312 the seed germination percentage progressively decreased over the control at all Cd levels. Various physiological and morphological parameters of the root and whole plant in both transgenic cotton cultivars and their relative wild cotton genotype respond differently towards the Cd toxicity. Bioavailability of Cd was concentration-dependent where seedling root captured more Cd as compared to shoot. BR001 accumulated more Cd followed by GK30, while Coker 312 was less Cd accumulator. The ultrastructural modifications in the root tip cells of both the transgenic cotton cultivars and their wild relative were also dose-dependent. With the increase in Cd levels, the fine structures of their root cells also invariably changed. Increase in plasmolysis of the plasma membrane, greater number of nucleoli and vacuoles and enlarged vacuoles could be observed in both transgenic cotton cultivars. In comparison to them, Coker 312 showed relatively well developed ultrastructures of the root tips except enlarged vacuoles and greater number of mitochondria. Moreover, the accumulation of Cd in the form of electron dense granules and crystals both in vacuoles and attached to cell walls were visible in both transgenic cotton cultivars and their wild relative. These results suggest that both transgenic cotton cultivars and their wild relative cotton genotype responded positively towards Cd stress at seedling stage, the internal Cd-detoxification might be through apoplastic and symplastic binding

Cadmium-induced functional and ultrastructural alterations in roots of two transgenic cotton cultivars

Energy Technology Data Exchange (ETDEWEB)

Daud, M.K.; Sun, Yuqiang; Dawood, M. [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Hayat, Y. [Institute of Bioinformatics, Zhejiang University, Hangzhou 310029 (China); Variath, M.T.; Wu Yuxiang [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Raziuddin [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Plant Breeding and Genetics Department, NWFP Agricultural University Peshawar, Peshawar (Pakistan); Mishkat, Ullah [Zoological Sciences Division, Pakistan Museum of Natural History, Garden Avenue, Shakarparian, Islamabad 44000 (Pakistan); Salahuddin [District Agriculture Extension Offices, Bannu Road, Dera Ismail Khan (NWFP) (Pakistan); Najeeb, Ullah [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Zhu, Shuijin [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China)], E-mail: shjzhu@zju.edu.cn

2009-01-15

The toxic effect of cadmium (Cd) at increasing concentrations was studied with special attention being given to the root morphological and ultrastructural changes in two transgenic cotton cultivars viz. BR001 and GK30 and their wild relative viz. Coker 312. In comparison to their respective controls, low concentration (10 and 100 {mu}M) of Cd greatly stimulated seed germination, while it was inhibited by highest concentration of Cd (1000 {mu}M) in case of two transgenic cultivars. However, in Coker 312 the seed germination percentage progressively decreased over the control at all Cd levels. Various physiological and morphological parameters of the root and whole plant in both transgenic cotton cultivars and their relative wild cotton genotype respond differently towards the Cd toxicity. Bioavailability of Cd was concentration-dependent where seedling root captured more Cd as compared to shoot. BR001 accumulated more Cd followed by GK30, while Coker 312 was less Cd accumulator. The ultrastructural modifications in the root tip cells of both the transgenic cotton cultivars and their wild relative were also dose-dependent. With the increase in Cd levels, the fine structures of their root cells also invariably changed. Increase in plasmolysis of the plasma membrane, greater number of nucleoli and vacuoles and enlarged vacuoles could be observed in both transgenic cotton cultivars. In comparison to them, Coker 312 showed relatively well developed ultrastructures of the root tips except enlarged vacuoles and greater number of mitochondria. Moreover, the accumulation of Cd in the form of electron dense granules and crystals both in vacuoles and attached to cell walls were visible in both transgenic cotton cultivars and their wild relative. These results suggest that both transgenic cotton cultivars and their wild relative cotton genotype responded positively towards Cd stress at seedling stage, the internal Cd-detoxification might be through apoplastic and symplastic

Ultrastructure of the extracellular matrix of bovine dura mater, optic nerve sheath and sclera.

Science.gov (United States)

Raspanti, M; Marchini, M; Della Pasqua, V; Strocchi, R; Ruggeri, A

1992-10-01

The sclera, the outermost sheath of the optic nerve and the dura mater have been investigated histologically and ultrastructurally. Although these tissues appear very similar under the light microscope, being dense connective tissues mainly composed of collagen bundles and a limited amount of cells and elastic fibres, they exhibit subtle differences on electron microscopy. In the dura and sclera collagen appears in the form of large, nonuniform fibrils, similar to those commonly found in tendons, while in the optic nerve sheath the fibrils appear smaller and uniform, similar to those commonly observed in reticular tissues, vessel walls and skin. Freeze-fracture also reveals these fibrils to have different subfibrillar architectures, straight or helical, which correspond to 2 distinct forms of collagen fibril previously described (Raspanti et al. 1989). The other extracellular matrix components also vary with the particular collagen fibril structure. Despite their common embryological derivation, the dura mater, optic nerve sheath and sclera exhibit diversification of their extracellular matrix consistent with the mechanical loads to which these tissues are subjected. Our observations indicate that the outermost sheath of the optic nerve resembles the epineurium of peripheral nerves rather than the dura to which it is commonly likened.

Ultrastructural analysis of the pigment dispersion syndrome in DBA/2J mice.

Science.gov (United States)

Schraermeyer, Mareike; Schnichels, Sven; Julien, Sylvie; Heiduschka, Peter; Bartz-Schmidt, Karl-Ulrich; Schraermeyer, Ulrich

2009-11-01

To characterise ocular pigment abnormalities associated with iris atrophy in DBA/2J mice as a model for human pigment dispersion syndrome. Immunohistochemistry, electron and light microscopy were performed to examine the eyes of DBA/2J mice ranging in age from 2.5 to 18 months old. The focus of our study was the description of the ultrastructural modifications in the irides of DBA/2J mice. The DBA/2J mice presented modifications in the melanosomes in all the pigmented parts of the eye, including the retinal pigment epithelial cells and choroidal melanocytes of the ciliary pigment epithelium. The extracellular matrix of the iris stroma disappeared with ageing. Pigmented cells detached from the iris and migrated into the trabecular meshwork exclusively on the anterior iris surface. These cells were identified as macrophages by immunohistochemistry and electron microscopy. There was no evidence that melanocytes or iris pigment epithelial cells migrated into the trabecular meshwork, but they became more and more depigmented. The aqueous outflow was blocked by pigment-laden cells, but not by cellular debris or melanosomes. No substantial amount of extracellular melanosomes was observed. The morphology of melanosomes is aberrant in all pigment cells in the eyes of DBA/2J mice. We conclude that the disease process begins with the transfer of both immature melanosomes from the iris pigment epithelium (IPE) and melanocytes to macrophages, which subsequently migrate into the trabecular meshwork. Accumulating macrophages cause a blockade of the chamber angle. As the disease progresses, the IPE, melanocytes and iris stroma, including blood vessels, disappear, leading to iris atrophy. It is speculated that the loss of these pigment cells is partly caused by reduction of the iris stroma.

Ultrastructure of the gut epithelium in Acheta domesticus after long-term exposure to nanodiamonds supplied with food.

Science.gov (United States)

Karpeta-Kaczmarek, Julia; Augustyniak, Maria; Rost-Roszkowska, Magdalena

2016-05-01

The biosafety of nanoparticles and the potential toxicity of nanopollutants and/or nanowastes are all currently burning issues. The increased use of nanoparticles, including nanodiamonds (ND), entails the real risk of their penetration into food chains, which may result in the contamination of animal and, as a result, human food. Knowledge about changes in the ultrastructure of tissues in organisms that have been exposed to ND is still very limited. The aim of the study was to describe the ultrastructure of the gut epithelium in Acheta domesticus after exposure to different concentrations of ND (0, 20 or 200 μg g(-1) - control, ND20 and ND200 groups, respectively) administered with food over a five-week period. The ultrastructure of the foregut, midgut and hindgut was assessed using Transmission Electron Microscopy (TEM). A number of changes in the structure of the gut in crickets that had consumed nanodiamond-contaminated food were observed. The epithelium of the midgut and hindgut were clearly damaged by ND, although the foregut was not affected. A positive relationship between the ND concentration in food and the degree of damage to the structure of epithelial cells was observed. Autophagy, especially mitophagy and reticulophagy, was activated in relation to the appearance of ND particles. A putative ND toxicity mechanizm is proposed. Extreme caution should be maintained when using nanodiamonds on a large scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ultrastructure and properties of Paecilomyces lilacinus spores

Energy Technology Data Exchange (ETDEWEB)

Holland, R.J.; Gunasekera, T.S. [Macquarie Univ., Dept. of Biological Sciences, Sydney (Australia); Williams, K.L. [Proteome Systems Ltd., Sydney (Australia); Nevalainen, K.M.H. [Dept. of Biological Sciences, Macquarie University, Sydney (Australia)

2002-10-01

Strains of the filamentous soil fungus Paecilomyces lilacinus are currently being developed for use as biological control agents against root-knot, cyst, and other plant-parasitic nematodes. The inoculum applied in the field consists mainly of spores. This study was undertaken to examine the size, ultrastructure, and rodlet layers of P. lilacinus spores and the effect of the culture method on structural and functional spore properties. A rodlet layer was identified on aerial spores only. Other differences noted between aerial spores and those produced in submerged culture included the size and appearance of spores and thickness of spore coat layers when examined with transmission electron microscopy. The two spore types differed in UV tolerance, with aerial spores being less sensitive to environmentally relevant UV radiation. Also, viability after drying and storage was better with the aerial spores. Both spore types exhibited similar nematophagous ability. (author)

Ultrastructure and properties of Paecilomyces lilacinus spores

International Nuclear Information System (INIS)

Holland, R.J.; Gunasekera, T.S.; Williams, K.L.; Nevalainen, K.M.H.

2002-01-01

Strains of the filamentous soil fungus Paecilomyces lilacinus are currently being developed for use as biological control agents against root-knot, cyst, and other plant-parasitic nematodes. The inoculum applied in the field consists mainly of spores. This study was undertaken to examine the size, ultrastructure, and rodlet layers of P. lilacinus spores and the effect of the culture method on structural and functional spore properties. A rodlet layer was identified on aerial spores only. Other differences noted between aerial spores and those produced in submerged culture included the size and appearance of spores and thickness of spore coat layers when examined with transmission electron microscopy. The two spore types differed in UV tolerance, with aerial spores being less sensitive to environmentally relevant UV radiation. Also, viability after drying and storage was better with the aerial spores. Both spore types exhibited similar nematophagous ability. (author)

Ultrastructure and pathology of desmoplastic small round cell tumor

International Nuclear Information System (INIS)

Xu Bin; Wang Bo; Gu Junlian; Li Xin; Li Yang

2010-01-01

Objective: To observe the change of ultrastructure and pathology of desmoplastic small round cell tumor (DSRCT) and recognize the characteristics of DSRCT and improve the standard of diagnosis. Methods: One case of primary DSRCT in right leg was observed by light microscope, immunohistochemical method and electron microscope and analyzed with review of the literatures. Results: The size of tumor was 3.2 cm x 2.4 cm x 1.3 cm with gray-yellow on cross-section. Foci of hemorrhage and necrosis were noted. Under light microscope, the tumor was composed of sharply demarcated nests of small rounded or oval cells. The cellular aggregates were surrounded and separated by abundant fibrous connective tissue. The tumor cells were uniform in size and shape, and showed small to moderate amounts of pale cytoplasm with indistinct cell borders. The nuclei were round to oval, with clumped chromatin and marked hyperchromasia. Some cells had one or two indistinct nucleoli. Numerous mitotic figures and areas of necrosis were dentified. The immunohistochemical results showed that the tumor cells were strongly positive for CK, EMA and NSE. There was focal positive staining for desmin with a perinuclear dot-like pattern. However, the tumor cells were negative for CgA, Myogenin, Syn, LCA, SMA, S-100, NF, GFAP, HMB45, HHF-35, CD3, CD10, Actin, CD99, and CD20. Under electron microscope, the tumor cells showed paranuclear cytoplasmic intermediate filaments arranging in globular or whorl array. Conclusion: DSRCT occurs both in the abdomen and at other sites. The patients with DSRCT range widely in age. DSRCT has distinctive histopathologic and ultrastructural features. This tumor shows immunohistochemical feature of epithelial, mesenchymal as well as neural multidirectional differentiation. RT-PCR may be served as an important diagnostic adjunct for DSRAT. The prognosis of the patients with DSRCT is very poor. (authors)

The first data on the vitellogenesis of paruterinid tapeworms: an ultrastructural study of Dictyterina cholodkowskii (Cestoda: Cyclophyllidea)

Czech Academy of Sciences Publication Activity Database

Yoneva, Aneta; Kuchta, Roman; Mariaux, J.; Georgiev, B. B.

2017-01-01

Roč. 116, č. 1 (2017), s. 327-334 ISSN 0932-0113 Institutional support: RVO:60077344 Keywords : ultrastructure * vitellocytes * vitelline vesicles * Cestode * Cyclophyllidean * Dictyterina cholodkowskii Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 2.329, year: 2016

Correlation between left ventricular diastolic function before and after valve replacement surgery and myocardial ultrastructural changes in patients with left ventricular volume-overloaded valvular heart diseases

International Nuclear Information System (INIS)

Okada, Tomiro

1993-01-01

Left ventricular (LV) diastolic functions in 23 patients with aortic regurgitation (AR) and 22 patients with mitral regurgitation (MR) were evaluated by gated blood pool scintigraphy. LV myocardial biopsy was performed during open heart surgery, and LV myocardial ultrastructural changes were evaluated by electron microscope. Correlation between LV diastolic function and myocardial ultrastructural changes was examined. It was suggested that preoperative LV diastolic dysfunction occurred earlier than LV systolic dysfunction in patients with AR and MR. LV early diastolic dysfunction was especially significant in patients with AR. LV systolic function was significantly improved postoperatively compared with LV diastolic function in patients with AR and MR. It was suggested that LV interstitial fibrosis caused LV diastolic dysfunction in patients with AR and MR, and insufficiency of myocardial thickening as compensation in patients with MR. It was presumed that LV diastolic dysfunction was irreversible in patients with AR and MR in the distant postoperative period due to persistence of the preoperative myocardial ultrastructural change, e.g., interstitial fibrosis. These LV diastolic indices measured by gated pool scintigraphy were useful in predicting LV ultrastructural changes and postoperative LV dysfunction in patients with LV volume-overloaded valvular heart disease. (author)

Scleral ultrastructure and biomechanical changes in rabbits after negative lens application

Directory of Open Access Journals (Sweden)

Xiao Lin

2018-03-01

Full Text Available AIM: To address the microstructure and biomechanical changes of the sclera of rabbits after negative lens application by spectacle frame apparatus. METHODS: Five New Zealand rabbits of seven weeks post-natal were treated with -8 D lens monocularly over the course of two weeks. Refractive errors and axial length (AXL were measured at the 1st, 7th and 14th days of the induction period. Ultrastructure of sclera was determined with electron microscopy. Biomechanical properties were tested by an Instron 5565 universal testing machine. RESULTS: Lens-induced (LI eyes elongated more rapidly compared with fellow eyes with AXL values of 15.56±0.14 and 15.21±0.14 mm (P<0.01. Fibril diameter was significantly smaller in the LI eyes compared with control ones in the inner, middle, and outer layers (inner layer, 63.533 vs 76.467 nm; middle layer, 92.647 vs 123.984 nm; outer layer, 86.999 vs 134.257 nm, P<0.01, respectively. In comparison with control eyes, macrophage-like cells that engulfed fibroblasts, dilated endoplasmic reticulum, and vacuoles in fibroblasts were observed in the inner and middle stroma in the LI eyes. Ultimate stress and Young’s modulus were lower in the LI eyes compared with those in the control eyes. CONCLUSION: Negative lens application alters eye growth, and results in axial elongation with changes in scleral ultrastructural and mechanical properties.

Ultrastructural characteristics of the vascular wall components of ruptured atherosclerotic abdominal aortic aneurysm

Directory of Open Access Journals (Sweden)

Tanasković Irena

2013-01-01

Full Text Available The aim of this study was to determine the ultrastructural characteristics of cell populations and extracellular matrix components in the wall of ruptured atherosclerotic abdominal aortic aneurysm (AAA. We analyzed 20 samples of ruptured AAA. For orientation to the light microscopy, we used routine histochemical techniques by standard procedures. For ultrastructural analysis, we applied transmission electron microscopy (TEM. Our results have shown that ruptured AAA is characterized by the remains of an advanced atherosclerotic lesion in the intima followed by a complete absence of endothelial cells, the disruption of basal membrane and disruption of internal elastic lamina. On plaque margins as well as in the inner media we observed smooth muscle cells (SMCs that posses a euchromatic nucleus, a well-developed granulated endoplasmic reticulum around the nucleus and reduced myofilaments. The remains of the ruptured lipid core were acellular in all samples; however, on the lateral sides of ruptured plaque we observed a presence of two types of foam cells (FCs, spindle- and star-shaped. Fusiform FCs possess a well-differentiated basal lamina, caveolae and electron dense bodies, followed by a small number of lipid droplets in the cytoplasm. Star-shaped FCs contain a large number of lipid droplets and do not possess basal lamina. On the inner margins of the plaque, we observed a large number of cells undergoing apoptosis and necrosis, extracellular lipid droplets as well as a large number of lymphocytes. The media was thinned out with disorganized elastic lamellas, while the adventitia exhibited leukocyte infiltration. The presented results suggest that atherosclerotic plaque in ruptured AAA contains vascular SMC synthetic phenotype and two different types of FCs: some were derived from monocyte/macrophage lineage, while others were derived from SMCs of synthetic phenotype. The striking plaque hypocellularity was the result of apoptosis and necrosis

Surface ultrastructure of Chrysomya rufifacies (Macquart) larvae (Diptera: Calliphoridae).

Science.gov (United States)

Sukontason, Kabkaew L; Sukontason, Kom; Lertthamnongtham, Sirisuda; Kuntalue, Budsabong; Thijuk, Natchanart; Vogtsberger, Roy C; Olson, Jimmy K

2003-05-01

The surface ultrastructure of all larval instars of Chrysomya rufifacies (Macquart) is described by means of scanning electron microscopy (SEM). Morphological changes were greatest from the first to the second instar, but less from the second to the third instar. Most of these changes involved the structure of the anterior spiracle, posterior spiracle, integument of the body, and mouthhooks. Modification of the mouthhooks, especially in the third instar, are helpful in explaining the ferocious feeding ability of the older maggots. The common name of "hairy-maggot" for C. rufifacies is only appropriate for the second and third instars because of their elongated tubercles along the body, whereas this name is not descriptive of the first instar that lack tubercles.

Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts

Directory of Open Access Journals (Sweden)

Sacchi L.

2001-06-01

Full Text Available The nurse cell-larva complex of nematodes of the genus Trichinella plays an Important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear, T. spiralis (horses and humans, T. pseudospiralis (a laboratory mouse and T. papuae (a laboratory mouse were examined. Analysis with transmission electron microscope showed that the typical nurse cell structure was present in all examined samples, irrespective of the species of larva, of the presence of a collagen capsule, of the age of infection and of the host species, suggesting that there exists a molecular mechanism that in the first stage of larva invasion is similar for encapsulated and non-encapsulated species.

Familial atrophia maculosa varioliformis cutis: an ultrastructural study.

Science.gov (United States)

Dall'Oglio, F; Nasca, M R; Taparelli, F; Bacchelli, B; Micali, G

2001-01-01

Atrophia maculosa varioliformis cutis is a rare and distinctive form of idiopathic facial macular noninflammatory atrophy that may rarely be observed in members of the same family. We describe two brothers, ages 14 and 16 years, with spontaneously appearing, asymptomatic, varioliform and linear atrophic lesions. Their past medical history was positive for varicella occurring in childhood without residual facial scarring. Routine laboratory investigations and screening for circulating autoantibodies were negative. Both patients were concordant for HLA A2 and DQ4.1. Routine and ultrastructural histologic examination of a punch biopsy specimen showed the presence of scarce, small, fragmented elastic fibers and compact collagen bundles associated with hypertrophic fibroblasts in the dermis. Our patients remained clinically stable, untreated, over a 2-year follow-up period. No long-term follow-up data have previously been reported.

Basicladia chelonum (Collins W.E. Hoffmann et Tilden (Chlorophyta, Cladophorophyceae from Cuba (Caribbean: new observation of the ultrastructure of its vegetative cells

Directory of Open Access Journals (Sweden)

Joanna Czerwik-Marcinkowska

2011-01-01

Full Text Available Basicladia chelonum (Collins W.E. Hoffmann and Tilden (1930 principally known from North America and Hawaii was recently (2004 found in Cuba (Caribbean from artificial pool growing on shells of musk turtles (Trachemys decussata Gray. Specimens collected in Cuba were subjected to detailed examinations also using a transmission electron microscope. On one hand, these studies confirmed many features of this species previously described by earlier authors in the specimens from Texas. On the other hand, the present studies revealed structures unknown so far (pyrenoid structure, which allowed for new analysis of this species. These investigations also have shown that Basicladia chelonum exhibits close similarity to the genus Cladophora and other representatives of the class Cladophorophyceae. The similarities include : siphonocladous level of organization of thallus, numerous chloroplasts forming a network and other structures. Conversely, the pyrenoid in vegetative cells of Basicladia chelonum distinguishes it markedly from representatives of the genus Cladophora, which have bilenticular pyrenoids divided into two hemispheres by a single thylakoids and each hemisphere is covered by a bowlshaped starch grain (Van Hoek et al. 1995. Since in Cladophora the ultrastructure of the pyrenoid is highly constant and characteristic, this contrasts with the genus Basicladia and, therefore, more firmly establishes position of the latter as an independent unit within Cladophorophyceae.

[Effect of low-intensity electromagnetic fields of industrial frequency on the ultrastructure and proliferative activity of rat's thymus cells].

Science.gov (United States)

Zhitkevich, T I; Bokut', T B; Netukova, N I

2001-01-01

Effects of two types of low-intensity electromagnetic fields (EMF) of industrial frequency (50 Hz) on the fine structure and proliferative activity of thymic cells in white rats were studied. It was found that a weak EMF with a prevailing electrical component (380-480 V/m, 120-140 nT1) did not affect the DNA synthesis intensity. An EMF with a stronger magnetic induction (10-15 V/m, 800-1500 nT1) diminished the glucose-6-phosphate dehydrogenase activity and proliferative processes in cultured stimulated lymphocytes. Electron microscopic investigation of the thymus after both types of exposure revealed an accumulation of lymphocytes with pyknotic nuclei and electron-dense cytoplasm, as well as hypoplasia of the vascular endothelium. At the same time, EMF with a prevailing magnetic component produced a more marked negative effect on the ultrastructure of thymic cells, which indicated a lowered secretory activity of epitheliocytes.

Ultrastructural observations on giardiasis in a mouse model. II. Endosymbiosis and organelle distribution in Giardia muris and Giardia lamblia.

Science.gov (United States)

Nemanic, P C; Owen, R L; Stevens, D P; Mueller, J C

1979-08-01

Ultrastructural observations of Giardia muris in a mouse model revealed endosymbiotic microbes not previously reported in Giardia. Endosymbionts 240--360 nm wide, 600--1,400 nm long, and with an internal structure similar to that of bacilli were not seen entering Giardia but were found and appeared to divide within Giardia. No evidence was found of digestion of the endosymbionts by the giardia host in either the trophozoite or the cyst form. Endosymbionts were concentrated centrally around the nuclear area and were uncommon in peripheral feeding regions. The same cellular organelles seen in G. muris were found in Giardia lamblia from human jejunal biopsy material, but no endosymbionts were identified in G. lamblia trophozoites from the seven patients examined. Endosymbionts within Giardia may be found to alter trophozoite pathogenicity, metabolism, range of infectivity, antigenic surface characteristics, and host specificity, as they do in other protozoa.

Ultrastructural aspects in perithecia hyphae septal pores of Glomerella cingulata F. SP. Phaseoli

OpenAIRE

Roca M.,María Gabriela; Ongarelli,Maria das Graças; Davide,Lisete Chamma; Mendes-Costa,Maria Cristina

2000-01-01

Glomerella cingulata (Stonem.) Spauld. & Schrenk f. sp. phaseoli, better known in its anamorphic state Colletotrichum lindemuthianum (Sacc. & Magn.) Briosi & Cav., is a causal agent of anthracnose in beans (Phaseolus vulgaris L.). Ultrastructural aspects of the perithecial hyphae of this pathogen were studied. The perithecia hyphae septal pores were found either plugged by a vesicle or unplugged. Some perithecia hyphae septa presented no pore. The Woronin bodies, close to the sept...

The effect of pneumatic tourniquets on the ultrastructure of skeletal muscle.

Science.gov (United States)

Patterson, S; Klenerman, L

1979-05-01

Experiments have been carried out on rhesus monkeys to determine the effect of the application of a pneumatic tourniquet on the ultrastructure of the muscles of the lower limb. Tourniquets were applied for periods lasting between one and five hours. The changes in the muscle lying immediately under the cuff of the tourniquet were more marked than those observed in muscle distal to the cuff. Three hours appears to be close to the limit of the time that a muscle can resist the sustained compression of a tourniquet.

The Effectiveness of Natural Diarylheptanoids against Trypanosoma cruzi: Cytotoxicity, Ultrastructural Alterations and Molecular Modeling Studies.

Directory of Open Access Journals (Sweden)

Vitor Sueth-Santiago

Full Text Available Curcumin (CUR is the major constituent of the rhizomes of Curcuma longa and has been widely investigated for its chemotherapeutic properties. The well-known activity of CUR against Leishmania sp., Trypanosoma brucei and Plasmodium falciparum led us to investigate its activity against Trypanosoma cruzi. In this work, we tested the cytotoxic effects of CUR and other natural curcuminoids on different forms of T. cruzi, as well as the ultrastructural changes induced in epimastigote form of the parasite. CUR was verified as the curcuminoid with more significant trypanocidal properties (IC50 10.13 μM on epimastigotes. Demethoxycurcumin (DMC was equipotent to CUR (IC50 11.07 μM, but bisdemethoxycurcumin (BDMC was less active (IC50 45.33 μM and cyclocurcumin (CC was inactive. In the experiment with infected murine peritoneal macrophages all diarylheptanoids were more active than the control in the inhibition of the trypomastigotes release. The electron microscopy images showed ultrastructural changes associated with the cytoskeleton of the parasite, indicating tubulin as possible target of CUR in T. cruzi. The results obtained by flow cytometry analysis of DNA content of the parasites treated with natural curcuminoids suggested a mechanism of action on microtubules related to the paclitaxel`s mode of action. To better understand the mechanism of action highlighted by electron microscopy and flow cytometry experiments we performed the molecular docking of natural curcuminoids on tubulin of T. cruzi in a homology model and the results obtained showed that the observed interactions are in accordance with the IC50 values found, since there CUR and DMC perform similar interactions at the binding site on tubulin while BDMC do not realize a hydrogen bond with Lys163 residue due to the absence of methoxyl groups. These results indicate that trypanocidal properties of CUR may be related to the cytoskeletal alterations.

Ovarian development of Caspian roach, Rutilus caspicus, in southern Caspian Sea: A histological and ultrastructural study

Directory of Open Access Journals (Sweden)

Maryam Akhoundian

2017-01-01

Full Text Available The histology and ultrastructure of the ovarian maturation process in Caspian roach, Rutilus caspicus, was studied. A total 170 female specimens were collected from the Gharasoo River, Bandar Turkmen, the southern Caspian Sea to evaluate its maturation cycle. Based on the results, its ovarian follicle’s development could classified into six stages by distinct characteristics. Minimum and maximum diameter of oocytes were recorded in the chromatin-nucleolus and maturation stages as 56.34±3.74 and 918.83±14.82 µm, respectively. The zona radiata was observed from the cortical alveoli stage and its maximum diameter measured in the secondary vitellogenesis stage as 93.11±23.0 µm. Gonadosomatic index (GSI reached to its peak in mid-March and its sharp drop in the late April showed its spawning period from late March or early April till the end of April. A positive correlation was found between the GSI and HSI in the vitellogenesis stage. The results also revealed Caspian roach as iteroparous synchronous spawner.

Desmosomes: A light microscopic and ultrastructural analysis of desmosomes in odontogenic cysts.

Science.gov (United States)

Raju, Pratima; Wadhwan, Vijay; Chaudhary, Minal S

2014-01-01

Desmosomes together with adherens junctions represent the major adhesive cell-cell junctions of epithelial cells. Any damage to these junctions leads to loss of structural balance. The present study was designed to analyze the desmosomal junctions in different odontogenic cysts and compare them with their corresponding hematoxylin and eosin (H and E)   stained sections. Ten cases each of odontogenic keratocyst (OKC), dentigerous cysts (DCs), radicular cysts (RCs) and normal mucosa were stained with hematoxylin and eosin. Scanning electron microscopy (SEM) analysis of the sections was then carried out of all the sections. The area of interest on H and E stained section was marked and this marking was later superimposed onto the corresponding unstained sections and were subjected to SEM analysis. OKC at ×1000 magnification showed many prominent desmosomes. However, an increase in the intercellular space was also noted. SEM analysis demonstrated similar findings with the presence of many desmosomes, though they were seen to be damaged and fragile. H and E stained DC under oil immersion did not show any prominent desmosomes. SEM analysis of the same confirmed the observation and very minimal number were seen with a very condense arrangement of the epithelial cells. RC at ×1000 magnification revealed plenty of desmosomes, which were again confirmed by SEM. The number and quality of desmosomal junctions in all the cysts has a role in the clinical behavior of the cyst.

Ultrastructural and biochemical investigations of protein mobilization of Mucuna pruriens (L.) DC. cotyledons and embryo axis.

Science.gov (United States)

Muccifora, Simonetta; Guerranti, Roberto; Muzzi, Chiara; Hope-Onyekwere, Nnadozies S; Pagani, Roberto; Leoncini, Roberto; Bellani, Lorenza M

2010-03-01

The mobilization of storage reserves, with particular emphasis on storage proteins of Mucuna pruriens (L.) DC., cotyledons, and embryo was investigated from the ultrastructural and biochemical points of view. Proteins and starch were the two main storage substances in cotyledons, and proteins and lipids were the main ones in the embryo. Embryo protein bodies were smaller and fewer in number than those of cotyledons. Structural and ultrastructural data determined between 24 and 48 h after imbibition and between 48 and 72 h after imbibition, the end of significant embryo and cotyledon protein mobilization, respectively, indicating more precocious storage protein mobilization in the axis than cotyledons. Moreover, storage protein mobilization in embryo and cotyledons occurred before the end of germination. Water soluble proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, producing 29 bands with molecular weights from 14 to 90 KDa. Embryo extract contained more proteins than cotyledon extract, contained seven characteristic bands, and showed a higher variability of the optical density trend than cotyledon.

Characteristics of the tomato chromoplast revealed by proteomic analysis

OpenAIRE

Barsan, Cristina; Sanchez-Bel, Paloma; Rombaldi, César Valmor; Egea, Isabel; Rossignol, Michel; Kuntz, Marcel; Zouine, Mohamed; Latché, Alain; Bouzayen, Mondher; Pech, Jean-Claude

2010-01-01

Chromoplasts are non-photosynthetic specialized plastids that are important in ripening tomato fruit (Solanum lycopersicum) since, among other functions, they are the site of accumulation of coloured compounds. Analysis of the proteome of red fruit chromoplasts revealed the presence of 988 proteins corresponding to 802 Arabidopsis unigenes, among which 209 had not been listed so far in plastidial databanks. These data revealed several features of the chromoplast. Proteins of lipid metabolism ...

Protective Effect of Vitamin E against Gamma Radiation Injury in Mice Histological and Ultrastructural Studies

International Nuclear Information System (INIS)

Abu Nour, S.M.; Abd EI Azeem, M.G.

2009-01-01

Vitamin E has been shown to ameliorate the effect of ionising radiation. The present study was designed to study the effect of high dose of gamma-radiation on the intestinal tissue of mice and the protective effect of the natural antioxidant vitamin E; a slow acting free radical scavenger. 24 adult albino male mice were divided into 4 groups (6 animals each). The first group represents the control group. The second experimental group received orally daily doses of vitamin E (100 mg/ kg body wt for 15 days). The third experimental group were exposed to 7 Gy gamma-rays as a single dose, while the fourth experimental group received vitamin E in the same dose before being irradiated. All animals were scarified and jejunal specimens were processed and prepared for histological and ultrastructural study after one day post irradiation. The results suggested that gamma-radiation induced different histological changes in the intestine of irradiated animals. Degeneration of the intestinal cells and microvilli were seen by light microscopic examination. SEM electron microscope (SEM) revealed haemorrhagic ulcerating tissues. In addition, the mitochondria were markedly swollen and loss of cristae, thickness of the terminal web zone was seen by transmission electron microscope. On the contrary, in animals treated with vitamin E, the intestinal tissues revealed structure almost similar to the control group. We conclude that vitamin E had protective effects against gamma-radiation induced oxidative stress

Subacute ghrelin administration inhibits apoptosis and improves ultrastructural abnormalities in remote myocardium post-myocardial infarction.

Science.gov (United States)

Eid, Refaat A; Zaki, Mohamed Samir Ahmed; Al-Shraim, Mubarak; Eleawa, Samy M; El-Kott, Attalla Farag; Al-Hashem, Fahaid H; Eldeen, Muhammad Alaa; Ibrahim, Hoja; Aldera, Hussain; Alkhateeb, Mahmoud A

2018-05-01

This study investigated the effect of ghrelin on cardiomyocytes function, apoptosis and ultra-structural alterations of remote myocardium of the left ventricle (LV) of rats, 21 days post myocardial infarction (MI). Rats were divided into 4 groups as a control, a sham-operated rats, a sham-operated+ghrelin, an MI + vehicle and an MI + ghrelin-treated rats. MI was induced by LAD ligation and then rats were recievd a concomitant doe of either normal saline as a vehicle or treated with ghrelin (100 μg/kg S.C., 2x/day) for 21 consecutive days. Ghrelin enhanced myocardial contractility in control rats and reversed the decreases in myocardial contractility and the increases in the serum levels of CK-MB and LDH in MI-induced rats. Additionally, it inhibited the increases in levels of Bax and cleaved caspase 3 and increased those for Bcl-2 in the remote myocardium of rat's LV, post-MI. At ultra-structural level, while ghrelin has no adverse effects on LV myocardium obtained from control or sham-treated rats, ghrelin post-administration to MI-induced rats reduced vascular formation, restored normal microfilaments appearance and organization, preserved mitochondria structure, and prevented mitochondrial swelling, collagen deposition and number of ghost bodies in the remote areas of their LV. Concomitantly, in remote myocardium of MI-induced rats, ghrelin enhanced endoplasmic reticulum intracellular organelles count, decreased number of atrophied nuclei and phagocytes, diminished the irregularity in the nuclear membranes and inhibited chromatin condensation. In conclusion, in addition to the physiological, biochemical and molecular evidence provided, this is the first study that confirms the anti-apoptotic effect of ghrelin in the remote myocardium of the LV during late MI at the level of ultra-structural changes. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Effects of management in gestational diabetes mellitus with normal prepregnancy body mass index on pregnancy outcomes and placental ultrastructures: a prospective cohort study.

Science.gov (United States)

Han, Yun; Zheng, Yan-Li; Wu, Ai-Min; Liu, Hong-Bin; Su, Jian-Bin; Lu, Xiao-Yan; Han, Yu-Wen; Ji, Jin-Long; Ji, Ju-Hua; Shi, Yue

2016-12-01

A great quantity of gestational diabetes mellitus with normal prepregnancy body mass index have emerged with the new criteria of gestational diabetes mellitus in China based on the International Diabetes in Pregnancy Consensus group criteria, and understanding placental changes and how they affect outcomes are necessary in order to develop effective management approach. The aim of this study was to prospectively explore the effect of active management starting from the late second trimester in gestational diabetes mellitus women with normal prepregnancy body mass index on pregnancy outcomes and placental ultrastructures, and to provide scientific evidences for optimizing the management of gestational diabetes mellitus in China. Gestational diabetes mellitus women with normal prepregnancy body mass index in the same period of this prospective cohort study were divided into intervention group (n = 51) and control group (n = 55). The intervention group was managed rigorously, while the control group received conventional prenatal cares. The glucose profile, gestational weight gain and pregnancy outcomes were followed up and placental ultrastructures were observed and recorded by transmission electron microscopy. The blood glucose level and gestational weight gain in intervention group were significantly better controlled than those in control group (P gestational age were significantly lower in intervention group than in control group (P gestational age (P gestational diabetes mellitus women with normal prepregnancy body mass index can improve pregnancy outcomes and placental ultrastructures, and the abnormal placental ultrastructure might be closely associated with the undesirable glycemic control and adverse pregnancy outcomes.

The ultrastructure of chloroplasts in variegata irregulare mutants of garden petunias (Petunia hybrida hort. superbissima

Directory of Open Access Journals (Sweden)

Stanisław Muszyński

2015-01-01

Full Text Available The ultrastructure of mutated chloroplasts in tetraploid garden petunias (Petunia hybrida hort. superbissima was analyzed by electron microscopy. The formation of grana structure is inhibited after secondary thylacoids start forming. Rapid dezintegration of the structure is observed. It is suggested that a substance responsible for photostabilization of grana structure is lacking.

Ultrastructure Organization of Collagen Fibrils and Proteoglycans of Stingray and Shark Corneal Stroma

Directory of Open Access Journals (Sweden)

Saud A. Alanazi

2015-01-01

Full Text Available We report here the ultrastructural organization of collagen fibrils (CF and proteoglycans (PGs of the corneal stroma of both the stingray and the shark. Three corneas from three stingrays and three corneas from three sharks were processed for electron microscopy. Tissues were embedded in TAAB 031 resin. The corneal stroma of both the stingray and shark consisted of parallel running lamellae of CFs which were decorated with PGs. In the stingray, the mean area of PGs in the posterior stroma was significantly larger than the PGs of the anterior and middle stroma, whereas, in the shark, the mean area of PGs was similar throughout the stroma. The mean area of PGs of the stingray was significantly larger compared to the PGs, mean area of the shark corneal stroma. The CF diameter of the stingray was significantly smaller compared to the CF diameter in the shark. The ultrastructural features of the corneal stroma of both the stingray and the shark were similar to each other except for the CFs and PGs. The PGs in the stingray and shark might be composed of chondroitin sulfate (CS/dermatan sulfate (DS PGs and these PGs with sutures might contribute to the nonswelling properties of the cornea of the stingray and shark.

Ultrastructural Changes during the Life Cycle of Mycoplasma salivarium in Oral Biopsies from Patients with Oral Leukoplakia

Directory of Open Access Journals (Sweden)

Harumi Mizuki

2017-09-01

Full Text Available Bacteria in genus Mycoplasma spp. are the smallest and simplest form of freely replicating bacteria, with 16 species known to infect humans. In the mouth, M. salivarium is the most frequently identified species. Mycoplasma spp. are parasites with small genomes. Although most of the Mycoplasma spp. that infect humans remain attached to the host cell surface throughout their life cycle, we have previously reported the presence of Mycoplasma salivarium in the epithelial cells of oral leukoplakia and oral lichen planus. However, the mechanism underlying the pathogenicity of M. salivarium has remained unclear. Further studies are needed to identify the process of infection of human cells and the stages in the life cycle of M. salivarium. Electron microscopy (EM is the method of choice for morphological investigation of Mycoplasma spp. in cells or tissues. This study was performed to clarify and detail the ultrastructure of M. salivarium in tissue biopsies of oral mucosal leukoplakia, using three EM methods: (1 a standard EM processing method; (2 an ultracryotomy and immunolabeling method; and (3 the LR White resin post-embedding and immunolabeling method. This study included five oral leukoplakia tissue samples showing hyperplasia and hyperkeratosis. Although there was some variation in ultrastructural appearances between the three EM methods used, there were four ultrastructural appearances that are believed to reflect the stages of the M. salivarium life cycle in the epithelial cells of the oral mucosa: (1 small, electron-dense cellular-like structures or elementary bodies of M. salivarium; (2 large structures of M. salivarium; (3 M. salivarium organisms in cell division; (4 the sequence of events in the life cycle of M. salivarium that includes: (a elementary bodies of M. salivarium deep in the oral mucosal epithelium; (b replication by binary fission and daughter cell division from the elementary bodies; (c maturation or degeneration of M

Ultrastructure of developing ascospores in Sordaria brevicollis.

Science.gov (United States)

Hackett, C J; Chen, K C

1976-05-01

The ultrastructure of ascospore wall formation in the pyrenomycete Sordaria brevicollis was studied in developing asci at progressive time intervals. From early spore delimitation through final stage of maturation, the wall of the ascospore differentiated into four composite layers, the periascosporium the delineation ascosporium, the subascosproium, and the endoascosproium, While ascospores were at the hyaline stage of development,they possessed only the periascosporium and delineation ascosporium as their wall components. At about 7 to 8 days from the initiation of the cross, the spores developed a yellow color, and this coloration was always associated with the elaboration of the subascorsporium just internal to the ascosporium. Asthe spores continued to progressively darken in color, the subascosporium was seen to increase in complexity, electron density, and thickness. Soon after the formation of the subascosporium, the endoascosporium began to develop de novo and was, therefore, the last wall layer formed as the spore approached maturity.

Alteration in the ultrastructural morphology of mycelial hyphae and the dynamics of transcriptional activity of lytic enzyme genes during basidiomycete morphogenesis.

Science.gov (United States)

Vetchinkina, Elena; Kupryashina, Maria; Gorshkov, Vladimir; Ageeva, Marina; Gogolev, Yuri; Nikitina, Valentina

2017-04-01

The morphogenesis of macromycetes is a complex multilevel process resulting in a set of molecular-genetic, physiological-biochemical, and morphological-ultrastructural changes in the cells. When the xylotrophic basidiomycetes Lentinus edodes, Grifola frondosa, and Ganoderma lucidum were grown on wood waste as the substrate, the ultrastructural morphology of the mycelial hyphal cell walls differed considerably between mycelium and morphostructures. As the macromycetes passed from vegetative to generative development, the expression of the tyr1, tyr2, chi1, chi2, exg1, exg2, and exg3 genes was activated. These genes encode enzymes such as tyrosinase, chitinase, and glucanase, which play essential roles in cell wall growth and morphogenesis.

Ultrastructure of the digestive system of Ramazzottius tribulosus and Macrobiotus richtersi (Eutardigrada in relationship with diet

Directory of Open Access Journals (Sweden)

Alexandra M. AVDONINA

2007-09-01

Full Text Available The ultrastructure of the digestive system of tardigrades was already described in some species, but it has never been studied in relationship to diet. We performed ultrastructural analyses of the midgut and hindgut of phytophagous Ramazzottius tribulosus and zoophagous Macrobiotus richtersi. In addition, the foregut of R. tribulosus was analyzed. New ultrastructural details have been observed. Among them are: (a distinct transverse pillar-like structures, lacking in electron-dense and compact cuticle of the buccal tube; (b a hole or groups of holes sometimes present in the buccal tube; (c a large cavity within each of the salivary glands where secreted mucus accumulates; and (d already found in zoophagous Isohypsibius prosostomus, one valve, formed by folds of the pharynx and located at the transition from pharynx to esophagus. In both analyzed species the increase of midgut surface is identified by two orders of folds of the gut wall and by microvilli. In R. tribulosus there are many first-order folds and few second-order folds, whereas in M. richtersi the opposite pattern is found. A peritrophic membrane and microvilli with a well developed glycocalyx are found only in the midgut lumen of R. tribulosus. The density of microvilli and the ratio between the real surface with microvilli and the hypothetical surface without microvilli is lower in zoophagous M. richtersi and I. prosostomus than in phytophagous R. tribulosus. All of these data represent an indirect indication of differences in digestive physiology between phytophagous and zoophagous tardigrade species. The shape of the hindgut is similar in both species and the lumen of the hindgut looks like a heartshaped cavity with some narrow cell evaginations.

Photosynthetic, antioxidative, molecular and ultrastructural responses of young cacao plants to Cd toxicity in the soil.

Science.gov (United States)

Pereira de Araújo, Romária; Furtado de Almeida, Alex-Alan; Silva Pereira, Lidiane; Mangabeira, Pedro A O; Olimpio Souza, José; Pirovani, Carlos P; Ahnert, Dário; Baligar, Virupax C

2017-10-01

Cadmium (Cd) is a highly toxic metal for plants, even at low concentrations in the soil. The annual production of world cocoa beans is approximately 4 million tons. Most of these fermented and dried beans are used in the manufacture of chocolate. Recent work has shown that the concentration of Cd in these beans has exceeded the critical level (0.6mgkg -1 DM). The objective of this study was to evaluate the toxicity of Cd in young plants of CCN 51 cacao genotype grown in soil with different concentrations of Cd (0, 0.05 and 0.1gkg -1 soil) through photosynthetic, antioxidative, molecular and ultrastructural changes. The increase of Cd concentration in the soil altered mineral nutrient absorption by competition or synergism, changed photosynthetic activity caused by reduction in chloroplastidic pigment content and damage to the photosynthetic machinery evidenced by the Fv/Fm ratio and expression of the psbA gene and increased GPX activity in the root and SOD in leaves. Additionally, ultrastructural alterations in roots and leaves were also evidenced with the increase of the concentration of Cd in the soil, whose toxicity caused rupture of biomembranes in root and leaf cells, reduction of the number of starch grains in foliar cells, increase of plastoglobules in chloroplasts and presence of multivesiculated bodies in root cells. It was concluded, therefore, that soil Cd toxicity caused damage to the photosynthetic machinery, antioxidative metabolism, gene expression and irreversible damage to root cells ultrastructure of CCN 51 cocoa plants, whose damage intensity depended on the exposure time to the metal. Copyright © 2017. Published by Elsevier Inc.

Ultrastructural changes in the flight muscle mitochondria of adult male mosquito Culex Pipiens L I

International Nuclear Information System (INIS)

Abd Elmeguid, A.; Elmoursy, A.A.; Rouchdy, H.; Elzahraa, F.

1995-01-01

Ultrastructural differences between differentiating myoblasts of 1-day old pupae and 2-day old pupae and between well developed flight muscles in newly emerged 1-day old and 2-day old and ageing 21-day old adult male Culex Pipiens were studied. Ageing mosquitoes showed various signs of deterioration, vocalization, fusion and disorientation of cristae. 6 figs

Effects of ultraviolet radiation and temperature on the ultrastructure of zoospores of the brown macroalga Laminaria hyperborea.

Science.gov (United States)

Steinhoff, F S; Wiencke, C; Müller, R; Bischof, K

2008-05-01

The interactive effects of an 8 h exposure to UV radiation and altered temperatures on the ultrastructure and germination of zoospores of the sublittoral brown alga Laminaria hyperborea (Gunn.) Foslie were investigated for the first time. Spores were exposed to four temperatures (2, 7, 12 and 17 degrees C) and three light regimes (PAR, PAR + UV-A, PAR + UV-A+UV-B). Freshly-released spores of L. hyperborea lack a cell wall and contain a nucleus with fine granular nucleoplasm and a nucleolus, one chloroplast, several mitochondria, dictyosomes and an endoplasmatic reticulum. Further, several kinds of so-called adhesive vesicles, lipid globuli and physodes containing UV-absorbing phlorotannins are embedded in the cytoplasm. No eye-spot is present. Physodes were found but they were rare and small. After an 8 h exposure to UV-B, the nucleoplasm had a mottled structure, chloroplasts contained plastoglobuli, the structure of the mitochondria changed from crista- to sacculus-type and germination was strongly inhibited at all temperatures. UV-A only had an impact on the ultrastructure at the highest temperature tested. The strongest effects were found at 17 degrees C, where germination was reduced to 35%, 32% and 9% after exposure to PAR, PAR+UV-A and PAR + UV-A + UV-B, respectively. This study indicates that UV-B radiation has strong damaging effects on the physiology and ultrastructure of zoospores of L. hyperborea. The results are important for developing scenarios for the effect of enhanced UV radiation and increasing temperatures caused by global climate changes.

Ultrastructural instability of paired helical filaments from corticobasal degeneration as examined by scanning transmission electron microscopy.

Science.gov (United States)

Ksiezak-Reding, H.; Tracz, E.; Yang, L. S.; Dickson, D. W.; Simon, M.; Wall, J. S.

1996-01-01

Paired helical filaments (PHFs) accumulate in the brains of subjects affected with Alzheimer's disease (AD) and certain other neurodegenerative disorders, including corticobasal degeneration (CBD). Electron microscope studies have shown that PHFs from CBD differ from those of AD by being wider and having a longer periodicity of the helical twist. Moreover, PHFs from CBD have been shown to be primarily composed of two rather than three highly phosphorylated polypeptides of tau (PHF-tau), with these polypeptides expressing no exons 3 and 10. To further explore the relationship between the heterogeneity of PHF-tau and the appearance of abnormal filaments, the ultrastructure and physical parameters such as mass per unit length and dimensions were compared in filaments from CBD and AD using high resolution scanning transmission electron microscopy (STEM). Filament-enriched fractions were isolated as Sarcosyl-insoluble pellets and for STEM studies, samples were freeze-dried without prior fixation or staining. Ultrastructurally, PHFs from CBD were shown to be a heterogeneous population as double- and single-stranded filaments could be identified based on their width and physical mass per unit length expressed in kilodaltons (kd) per nanometer (nm). Less abundant, double-stranded filaments had a maximal width of 29 nm and a mass per unit length of 133 kd/nm, whereas three times more abundant single-stranded filaments were 15 nm wide and bad a mass per unit length of 62 kd/nm. Double-stranded filaments also displayed a distinct axial region of less dense mass, which appeared to divide the PHFs into two protofilament-like strands. Furthermore, these filaments were frequently observed to physically separate along the long axis into two single strands or to break longitudinally. In contrast, PHFs from AD were ultrastructurally stable and uniform both in their width (22 nm) and physical mass per unit length (104 kd/nm). The ultrastructural features indicate that filaments of

Effect of c-myc on the ultrastructural structure of cochleae in guinea pigs with noise induced hearing loss

Energy Technology Data Exchange (ETDEWEB)

Han, Yu; Zhong, Cuiping [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Hong, Liu [First Division of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Wang, Ye; Qiao, Li [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Qiu, Jianhua, E-mail: qiujh@fmmu.edu.cn [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China)

2009-12-18

Noise over-stimulation may induce hair cells loss and hearing deficit. The c-myc oncogene is a major regulator for cell proliferation, growth, and apoptosis. However, the role of this gene in the mammalian cochlea is still unclear. The study was designed to firstly investigate its function under noise condition, from the aspect of cochlear ultrastructural changes. We had established the adenoviral vector of c-myc gene and delivered the adenovirus suspension into the scala tympani of guinea pigs 4 days before noise exposure. The empty adenoviral vectors were injected as control. Then, all subjects were exposed to 4-kHz octave-band noise at 110 dB SPL for 8 h/day, 3 days consecutively. Auditory thresholds were assessed by auditory brainstem response, prior to and 7 days following noise exposure. On the seventh days after noise exposure, the cochlear sensory epithelia surface was observed microscopically and the cochleae were taken to study the ultrastructural changes. The results indicated that auditory threshold shift after noise exposure was higher in the ears treated with Ad.EGFP than that treated with Ad.c-myc-EGFP. Stereocilia loss and the disarrangement of outer hair cells were observed, with greater changes found in the Ad.EGFP group. Also, the ultrastructure changes were severe in the Ad.EGFP group, but not obvious in the Ad.c-myc-EGFP group. Therefore, c-myc gene might play an unexpected role in hearing functional and morphological protection from acoustic trauma.

Effect of c-myc on the ultrastructural structure of cochleae in guinea pigs with noise induced hearing loss

International Nuclear Information System (INIS)

Han, Yu; Zhong, Cuiping; Hong, Liu; Wang, Ye; Qiao, Li; Qiu, Jianhua

2009-01-01

Noise over-stimulation may induce hair cells loss and hearing deficit. The c-myc oncogene is a major regulator for cell proliferation, growth, and apoptosis. However, the role of this gene in the mammalian cochlea is still unclear. The study was designed to firstly investigate its function under noise condition, from the aspect of cochlear ultrastructural changes. We had established the adenoviral vector of c-myc gene and delivered the adenovirus suspension into the scala tympani of guinea pigs 4 days before noise exposure. The empty adenoviral vectors were injected as control. Then, all subjects were exposed to 4-kHz octave-band noise at 110 dB SPL for 8 h/day, 3 days consecutively. Auditory thresholds were assessed by auditory brainstem response, prior to and 7 days following noise exposure. On the seventh days after noise exposure, the cochlear sensory epithelia surface was observed microscopically and the cochleae were taken to study the ultrastructural changes. The results indicated that auditory threshold shift after noise exposure was higher in the ears treated with Ad.EGFP than that treated with Ad.c-myc-EGFP. Stereocilia loss and the disarrangement of outer hair cells were observed, with greater changes found in the Ad.EGFP group. Also, the ultrastructure changes were severe in the Ad.EGFP group, but not obvious in the Ad.c-myc-EGFP group. Therefore, c-myc gene might play an unexpected role in hearing functional and morphological protection from acoustic trauma.

Ultrastructural morphology and phylogeny of Henneguya gilbert n. sp. (Myxozoa) infecting the teleostean Cyphocharax gilbert (Characiformes: Curimatidae) from Brazil.

Science.gov (United States)

Casal, Graça; São Clemente, Sérgio C; Lopes, Leila; Rocha, Sónia; Felizardo, Nilza; Oliveira, Elsa; Al-Quraishy, Saleh; Azevedo, Carlos

2017-10-01

This paper describes light and ultrastructural observations and molecular analysis of a fish-infecting myxosporean, Henneguya gilbert n. sp., which was found infecting the gill epithelium of the commercially important freshwater teleost fish Cyphocharax gilbert (Curimatidae) collected in the estuarine region of Guandu River, Rio de Janeiro State, Brazil. The parasite occurs in the gills, forming whitish spherical to ellipsoidal polysporic cysts measuring up to ~ 750 μm, and displaying asynchronous development. Mature myxospores are ellipsoidal with a bifurcated caudal process. The length, width and thickness of the body of the myxospore are 12.0 × 5.3 × 3.6 μm, respectively; two equal caudal processes are 16.8 μm long, and the total length of the myxospore is 27.2 μm. There are two unequal polar capsules: the larger measures 5.5 μm length × 1.3 μm width and has a polar filament with 9-10 coils; the smaller is 4.0 μm long × 1.3 μm wide and has a polar filament with 7-8 coils. The sporoplasm is binucleated and presents a spherical vacuole surrounded by numerous globular sporoplasmosomes. Phylogenetic analysis, based on the small subunit rRNA sequencing, using maximum likelihood method reveals the parasite clustering together with other myxobolids that are histozoic and parasitize freshwater fish of the order Characiformes, thereby strengthening the contention that the host phylogenetic relationships and aquatic environment are the strongest evolutionary signals for myxosporeans of the family Myxobolidae.

Organization of cytokeratin cytoskeleton and germ plasm in the vegetal cortex of Xenopus laevis oocytes depends on coding and non-coding RNAs: Three-dimensional and ultrastructural analysis

International Nuclear Information System (INIS)

Kloc, Malgorzata; Bilinski, Szczepan; Dougherty, Matthew T.

2007-01-01

Recent studies discovered a novel structural role of RNA in maintaining the integrity of the mitotic spindle and cellular cytoskeleton. In Xenopus laevis, non-coding Xlsirts and coding VegT RNAs play a structural role in anchoring localized RNAs, maintaining the organization of the cytokeratin cytoskeleton and germinal granules in the oocyte vegetal cortex and in subsequent development of the germline in the embryo. We studied the ultrastructural effects of antisense oligonucleotide driven ablation of Xlsirts and VegT RNAs on the organization of the cytokeratin, germ plasm and other components of the vegetal cortex. We developed a novel method to immunolabel and visualize cytokeratin at the electron microscopy level, which allowed us to reconstruct the ultrastructural organization of the cytokeratin network relative to the components of the vegetal cortex in Xenopus oocytes. The removal of Xlsirts and VegT RNAs not only disrupts the cytokeratin cytoskeleton but also has a profound transcript-specific effect on the anchoring and distribution of germ plasm islands and their germinal granules and the arrangement of yolk platelets within the vegetal cortex. We suggest that the cytokeratin cytoskeleton plays a role in anchoring of germ plasm islands within the vegetal cortex and germinal granules within the germ plasm islands

Expression dynamics and ultrastructural localization of epitope-tagged Abutilon mosaic virus nuclear shuttle and movement proteins in Nicotiana benthamiana cells

International Nuclear Information System (INIS)

Kleinow, Tatjana; Tanwir, Fariha; Kocher, Cornelia; Krenz, Bjoern; Wege, Christina; Jeske, Holger

2009-01-01

The geminivirus Abutilon mosaic virus (AbMV) encodes two proteins which are essential for viral spread within plants. The nuclear shuttle protein (NSP) transfers viral DNA between the nucleus and cytoplasm, whereas the movement protein (MP) facilitates transport between cells through plasmodesmata and long-distance via phloem. An inducible overexpression system for epitope-tagged NSP and MP in plants yielded unprecedented amounts of both proteins. Western blots revealed extensive posttranslational modification and truncation for MP, but not for NSP. Ultrastructural examination of Nicotiana benthamiana tissues showed characteristic nucleopathic alterations, including fibrillar rings, when epitope-tagged NSP and MP were simultaneously expressed in leaves locally infected with an AbMV DNA A in which the coat protein gene was replaced by a green fluorescent protein encoding gene. Immunogold labelling localized NSP in the nucleoplasm and in the fibrillar rings. MP appeared at the cell periphery, probably the plasma membrane, and plasmodesmata.

Postoperative diffuse opacification of a hydrophilic acrylic intraocular lens: analysis of an explant.

Science.gov (United States)

Cavallini, Gian Maria; Volante, Veronica; Campi, Luca; De Maria, Michele; Fornasari, Elisa; Urso, Giancarlo

2017-06-14

We describe the clinicopathological and ultrastructural features of an opaque single-piece hydrophilic acrylic intraocular lens (IOL) explanted from a patient. The main outcome of this report is the documentation of calcium deposits confirmed by surface analysis. The decrease in visual acuity was due to the opacification of the IOL. The opacification involved both the optic plate and the haptics. The analysis at the scansion electron microscope revealed that the opacity was caused by the deposition of calcium and phosphate within the lens optic and haptics. This is the first case about the opacification of an Oculentis L-313. The opacification was characterized by calcium and phosphate deposition probably due to a morphological alteration of the posterior surface of the IOL.

The ultrastructure and processing properties of Straumann Bone Ceramic and NanoBone.

Science.gov (United States)

Dietze, S; Bayerlein, T; Proff, P; Hoffmann, A; Gedrange, T

2006-02-01

The ultrastructure, fundamental chemistry, and processing modes of fully synthetic bone grafting materials are relevant to the reconstruction of osseous defects. Rapid progress in the profitable market of biomaterials has led to the development of various bone substitutes. Despite all these efforts, an ideal and full substitute of autologous bone is not yet in sight. With regard to anorganic calcium phosphate ceramics, Straumann Bone Ceramic and NanoBone are compared. These have a similar composition and are osteoconductive, which indispensably requires contact with well-vascularised bone.

Ultrastructural characterization of primary cilia in pathologically characterized human glioblastoma multiforme (GBM) tumors.

Science.gov (United States)

Moser, Joanna J; Fritzler, Marvin J; Rattner, Jerome B

2014-01-01

Primary cilia are non-motile sensory cytoplasmic organelles that are involved in cell cycle progression. Ultrastructurally, the primary cilium region is complex, with normal ciliogenesis progressing through five distinct morphological stages in human astrocytes. Defects in early stages of ciliogenesis are key features of astrocytoma/glioblastoma cell lines and provided the impetus for the current study which describes the morphology of primary cilia in molecularly characterized human glioblastoma multiforme (GBM) tumors. Seven surgically resected human GBM tissue samples were molecularly characterized according to IDH1/2 mutation status, EGFR amplification status and MGMT promoter methylation status and were examined for primary cilia expression and structure using indirect immunofluorescence and electron microscopy. We report for the first time that primary cilia are disrupted in the early stages of ciliogenesis in human GBM tumors. We confirm that immature primary cilia and basal bodies/centrioles have aberrant ciliogenesis characteristics including absent paired vesicles, misshaped/swollen vesicular hats, abnormal configuration of distal appendages, and discontinuity of centriole microtubular blades. Additionally, the transition zone plate is able to form in the absence of paired vesicles on the distal end of the basal body and when a cilium progresses beyond the early stages of ciliogenesis, it has electron dense material clumped along the transition zone and a darkening of the microtubules at the proximal end of the cilium. Primary cilia play a role in a variety of human cancers. Previously primary cilia structure was perturbed in cultured cell lines derived from astrocytomas/glioblastomas; however there was always some question as to whether these findings were a cell culture phenomena. In this study we confirm that disruptions in ciliogenesis at early stages do occur in GBM tumors and that these ultrastructural findings bear resemblance to those previously

Ultrastructural localization of human papilloma virus by nonradioactive in situ hybridization on tissue of human cervical intraepithelial neoplasia

DEFF Research Database (Denmark)

Multhaupt, H A; Rafferty, P A; Warhol, M J

1992-01-01

BACKGROUND: A nonradioactive in situ hybridization was developed to localize human papilloma virus (HPV) at the ultrastructural level. EXPERIMENTAL DESIGN: Cervical biopsies from human uterine cervices clinically suspicious of condyloma were embedded in Lowicryl K4M at low temperature...

Ultrastructural localization of lead in Stigeoclonium tenue (chlorophyceae, ulotrichales) as demonstrated by cytochemical and x-ray microanalysis

Energy Technology Data Exchange (ETDEWEB)

Silverberg, B A

1975-12-01

Results of ultrastructural studies and TEM-X-ray microanalysis of the ulotrichalean alga Stigeoclonium tenue experimentally exposed to increasing concentrations of lead nitrate are presented. A fine-structural examination of the cells revealed that detectable amounts of lead (Pb) had entered the cytoplasm and could be recognized most easily as electron-dense precipitates localized on the cell wall and within the two large peripheral vacuoles. Dense deposits were never observed in mitochondria, plastids or nuclei. Pinocytotic vacuoles containing lead spheroids are removed endocytotically to the cytoplasmic vacuoles, rendering the Pb innocuous. The evidence suggests that the cell wall and vacuoles are important structures in maintaining a relatively low cytoplasmic concentration of lead, thereby reducing the toxic effects of lead ions on sensitive cellular functions. At high concentrations, ranging from 0.15 to 0.5 mg Pb/l, noticeable alterations in the fine structure of the chloroplast are evident. A method is described for the visualization of Pb deposits in fresh, chemically fixed and plastic-embedded material using a saturated solution of sodium rhodizonate.

Metschnikowia cf. typographi and other pathogens from the bark beetle Ips sexdentatus - Prevalence, histological and ultrastructural evidence, and molecular characterization

DEFF Research Database (Denmark)

Kleespies, Regina G; Lim, Young Woon; Tkaczuk, Cezary

2017-01-01

Ips sexdentatus (six-spined engraver beetle) from Austria and Poland were dissected and examined for the presence of pathogens. Specimens collected in Austria were found to contain the ascomycetous fungus Metschnikowia cf. typographi. Infection rates ranged from 3.6% to 26.8% at different...... collection sites. M. cf. typographi infected midguts were investigated by histological, ultrastructural and molecular techniques. Extraordinary ultrastructural details are shown, such as ascospores with bilateral flattened flanks resembling alar rims at both sides of their attenuating tube-like ends....... The eugregarine Gregarina typographi was diagnosed most frequently. Infection rates of all I. sexdentatus specimens ranged from 21.4% to 71.9% in Austria and 54.1% to 68.8% in Poland. Other entomopathogenic protists, bacteria, or viruses were not detected....

The role of immunohistochemistry, electron microscopy, and ultrastructural cytochemistry in the diagnosis of mixed carcinoma-neuroendocrine neoplasms.

Science.gov (United States)

Graham, A R; Payne, C M; Nagle, R B; Angel, E

1987-02-01

We studied four mixed carcinoma-neuroendocrine neoplasms from gastrointestinal tract and pancreas by routine light microscopy (LM), immunohistochemistry (IH), electron microscopy (EM), and ultrastructural cytochemistry (UC). By LM, the individual tumors showed fairly pure neuroendocrine (carcinoid) or epithelial (papillary) patterns, mixed neuroendocrine-carcinoma features and poorly-differentiated tumor in sheets and nests which did not lend itself to morphologic characterization. IH demonstrated mixed expression, within different areas of the same neoplasm, of epithelial antigens (keratins and carcinoembryonic antigen [CEA]) and neuroendocrine markers (neuron-specific enolase [NSE], bombesin and neurohormonal peptides). By EM, each tumor showed ultrastructural features of epithelial and neuroendocrine differentiation which varied substantially in terms of number of cells involved and their distribution; two of the neoplasms showed biphasic differentiation within single cells. The nature of the neurosecretory granules was verified with the uranaffin reaction (UR). This study illustrates the value of combining LM, IH, EM and UC for the identification of mixed carcinoma-neuroendocrine lesions.

Dietary cadmium and enteropathy in the Japanese quail: histochemical and ultrastructural studies

Energy Technology Data Exchange (ETDEWEB)

Richardson, M.E.; Fox, M.R.S.

1974-01-01

Cadmium was fed to young Japanese quail, at a level of 75 mg. per kg. of diet, from hatching to 4 weeks of age. Cadmium produced gross, microscopic, and ultrastructural lesions in the proximal small intestine of these quail, similar to those occurring in human malabsorption syndromes, celiac disease, nontropical sprue, and tropical sprue. The small intestines of the quail were dilated and thin walled. Villi were short and thick and had a dense cellular infiltrate in the lamina propria. The striated border was thin but stained for neutral mucopolysaccharides, as did the normal border. Some villi were covered with stratified epithelial cells. Hypertrophy and hyperplasia of goblet were seen, but the mucin stained for weakly acidic mucopolysaccharides, as did the normal cells. At the ultrastructural level, microvilli of both absorptive and goblet cells were markedly shortened, particularly near the tips of the villi. Absorptive cells were atrophic, and there was s diminution of the usual cellular organelles. Granular cisternae were long and tortuous, mitochondria were dense and small, and large lysosome-like bodies and large lipid droplets accumulated in the cytoplasm, but there was a decrease in the normal small, pale and dark lipid droplets. The cellular infiltrate of the lamina propria included groups of plasma cells with dilated cisternae. There were large, irregular, electron-dense bodies in the endothelium of large veins and degeneration of some nerve plexuses in the muscularis propria. 31 references, 21 figures.

Comparative ultrastructure of fruit plastids in three genetically diverse genotypes of apple (Malus × domestica Borkh.) during development.

Science.gov (United States)

Schaeffer, Scott M; Christian, Ryan; Castro-Velasquez, Nohely; Hyden, Brennan; Lynch-Holm, Valerie; Dhingra, Amit

2017-10-01

Comparative ultrastructural developmental time-course analysis has identified discrete stages at which the fruit plastids undergo structural and consequently functional transitions to facilitate subsequent development-guided understanding of the complex plastid biology. Plastids are the defining organelle for a plant cell and are critical for myriad metabolic functions. The role of leaf plastid, chloroplast, is extensively documented; however, fruit plastids-chromoplasts-are poorly understood, especially in the context of the diverse metabolic processes operating in these diverse plant organs. Recently, in a comparative study of the predicted plastid-targeted proteomes across seven plant species, we reported that each plant species is predicted to harbor a unique set of plastid-targeted proteins. However, the temporal and developmental context of these processes remains unknown. In this study, an ultrastructural analysis approach was used to characterize fruit plastids in the epidermal and collenchymal cell layers at 11 developmental timepoints in three genotypes of apple (Malus × domestica Borkh.): chlorophyll-predominant 'Granny Smith', carotenoid-predominant 'Golden Delicious', and anthocyanin-predominant 'Top Red Delicious'. Plastids transitioned from a proplastid-like plastid to a chromoplast-like plastid in epidermis cells, while in the collenchyma cells, they transitioned from a chloroplast-like plastid to a chloro-chromo-amyloplast plastid. Plastids in the collenchyma cells of the three genotypes demonstrated a diverse array of structures and features. This study enabled the identification of discrete developmental stages during which specific functions are most likely being performed by the plastids as indicated by accumulation of plastoglobuli, starch granules, and other sub-organeller structures. Information regarding the metabolically active developmental stages is expected to facilitate biologically relevant omics studies to unravel the complex

Ultrastructure of the anterior organ and posterior funnel-shaped canal of Gyrocotyle urna Wagener, 1852 (Cestoda: Gyrocotylidea)

Czech Academy of Sciences Publication Activity Database

Poddubnaya, L. G.; Kuchta, Roman; Bristow, G.A.; Scholz, Tomáš

2015-01-01

Roč. 62, 2015 May 22 (2015), 027 ISSN 1803-6465 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : scanning electron microscopy * transmission electron microscopy * basal cestodes * ultrastructural characters * phylogeny Subject RIV: EG - Zoology Impact factor: 1.271, year: 2015

Comparative ultrastructure of the cuticle of trichostrongyle nematodes.

Science.gov (United States)

Beveridge, I; Durette-Desset, M C

1994-09-01

The ultrastructure of the cuticle was examined in Austrostrongylus victoriensis, Patricialina birdi and Woolleya monodelphis (Herpetostrongylidae) from marsupials, Paraustrostrongylus ratti (Herpetostrongylidae) from rodents, Nippostrongylus magnus and Odilia bainae (Heligmonellidae) from rodents, Cooperia oncophora and Camelostrongylus mentulatus (Trichostrongylidae) from ruminants, and Nematodirus spathiger (Molineidae) from ruminants. The principal cuticular layers described previously were present in all species investigated. Major differences in the shape and composition of cuticular struts were observed as well as differences in components of the median zone of the cuticle, including the fluid-filled regions present in several species. Several different types of strut were observed. Although strut structure within the Heligmonellidae appeared to be constant, there were variations within both the Herpetostrongylidae and Trichostrongylidae. In Nem. spathiger the cuticular ridges lacked struts. The diversity of structures found in the species examined suggests that more extensive comparative studies of the trichostrongyle cuticle are warranted.

[Lattice degeneration of the peripheral retina: ultrastructural study].

Science.gov (United States)

Bec, P; Malecaze, F; Arne, J L; Mathis, A

1985-01-01

The ultrastructural study of a case of snail track degeneration shows the presence of lipid inclusions in both the glial and the macrophage cells in every layer of the retina, and the existence of intraretinal fibers different from collagen fibers appearing to be glial filaments similar to those found in astrocytic gliomes and to the Rosenthal fibers observed in senile nervous cells. Other features were thinning of the retina and absence of blood vessels in the retina. There are no abnormalities of the vitreo-retinal juncture. All the lesions are in agreement with those observed by Daicker [Ophthalmologica, Basel 165: 360-365, 1972; Klin. Mbl. Augenheilk. 172: 581-583, 1978] with some differences, however. They are different from those found in lattice degeneration. They show that snail track degeneration is a specific form of peripheral retinal degeneration which is quite different from lattice degeneration and must not be considered similar.

Ultrastructure of the salivary glands in Lithobius forficatus (Myriapoda, Chilopoda, Lithobiidae) according to seasonal and circadian rhythms.

Science.gov (United States)

Kamińska, K; Włodarczyk, A; Sonakowska, L; Ostróżka, A; Marchewka, A; Rost-Roszkowska, M

2016-11-01

The salivary glands (mandibular epidermal glands) of adult males and females of Lithobius forficatus (Myriapoda, Chilopoda) were isolated during spring, summer and autumn. In addition, the organs were isolated at different times of the day - at about 12:00 (noon) and about 00:00 (midnight). The ultrastructure of these organs depending on seasonal and circadian rhythms was analyzed using transmission and scanning electron microscopy and histochemical methods. The paired salivary glands of L. forficatus are situated in the vicinity of the foregut and they are formed by numerous acini that are surrounded by the fat body, hemocytes and tracheolae. The salivary glands are composed of a terminal acinar component and a system of tubular ducts that are lined with a cuticle. The glandular part is composed of secretory epithelial cells that are at various stages of their secretory activity. The saliva that is produced by the secretory cells of the acini is secreted into the salivary ducts, which are lined with a simple epithelium that is based on the non-cellular basal lamina. The ultrastructural variations suggest that salivary glands function differently depending on seasonal rhythms and prepare the animal for overwintering. Therefore, the salivary glands of the centipedes that were analyzed participate in the accumulation of proteins, lipids and polysaccharides during the spring, summer and autumn. Subtle differences in the ultrastructure of the secretory cells of the salivary glands during the circadian cycle must be related to the physiological reactions of the organism. The salivary ducts showed no differences in the specimens that were analyzed during the day/night cycle or during the seasonal cycle. Copyright © 2016 Elsevier Ltd. All rights reserved.

A comparative ultrastructural study of pit membranes with plasmodesmata associated thickenings in four angiosperm species.

Science.gov (United States)

Rabaey, David; Lens, Frederic; Huysmans, Suzy; Smets, Erik; Jansen, Steven

2008-11-01

Recent micromorphological observations of angiosperm pit membranes have extended the number and range of taxa with pseudo-tori in tracheary elements. This study investigates at ultrastructural level (TEM) the development of pseudo-tori in the unrelated Malus yunnanensis, Ligustrum vulgare, Pittosporum tenuifolium, and Vaccinium myrtillus in order to determine whether these plasmodesmata associated thickenings have a similar developmental pattern across flowering plants. At early ontogenetic stages, the formation of a primary thickening was observed, resulting from swelling of the pit membrane in fibre-tracheids and vessel elements. Since plasmodesmata appear to be frequently, but not always, associated with these primary pit membrane thickenings, it remains unclear which ultrastructural characteristics control the formation of pseudo-tori. At a very late stage during xylem differentiation, a secondary thickening is deposited on the primary pit membrane thickening. Plasmodesmata are always associated with pseudo-tori at these final developmental stages. After autolysis, the secondary thickening becomes electron-dense and persistent, while the primary thickening turns transparent and partially or entirely dissolves. The developmental patterns observed in the species studied are similar and agree with former ontogenetic studies in Rosaceae, suggesting that pseudo-tori might be homologous features across angiosperms.

Ultrastructural and Molecular Changes in the Developing Small Intestine of the Toad Bufo regularis

Directory of Open Access Journals (Sweden)

S. A. Sakr

2014-01-01

Full Text Available The ontogenetic development of the small intestine of the toad Bufo regularis was investigated using twofold approaches, namely, ultrastructural and molecular. The former has been done using transmission electron microscope and utilizing the developmental stages 42, 50, 55, 60, 63, and 66. The most prominent ultrastructural changes were recorded at stage 60 and were more evident at stage 63. These included the appearance of apoptotic bodies/nuclei within the larval epithelium, the presence of macrophages, swollen mitochondria, distorted rough endoplasmic reticulum, chromatin condensation, and irregular nuclear envelop, and the presence of large vacuoles and lysosomes. The molecular investigation involved examining DNA content and fragmentation. The results showed that the DNA content decreased significantly during the metamorphic stages 60 and 63 compared with both larval (50 and 55 and postmetamorphic (66 stages. The metamorphic stages (60 and 63 displayed extensive DNA laddering compared with stages 50, 55, and 66. The percentage of DNA damage was 0.00%, 12.91%, 57.26%, 45.48%, and 4.43% for the developmental stages 50, 55, 60, 63, and 66, respectively. In conclusion, the recorded remodeling of the small intestine represents a model for clarifying the mechanism whereby cell death and proliferation are controlled.

EVALUATION OF THE ULTRASTRUCTURE OF THE SMALL INTESTINE OF HIV INFECTED CHILDREN BY TRANSMISSION AND SCANNING ELECTRONIC MICROSCOPY

Directory of Open Access Journals (Sweden)

Christiane Araujo Chaves LEITE

2013-03-01

Full Text Available Objectives To describe HIV children's small intestinal ultrastructural findings. Methods Descriptive, observational study of small intestine biopsies performed between August 1994 and May 1995 at São Paulo, SP, Brazil. This material pertained to 11 HIV infected children and was stored in a laboratory in paraffin blocks. Scanning and transmission electronic microscopy were used to view those intestine samples and ultrastructural findings were described by analyzing digitalized photos of this material. Ethical Committee approval was obtained. Results In most samples scanning microscopy showed various degrees of shortening and decreasing number of microvilli and also completes effacements in some areas. Derangement of the enterocytes was seen frequently and sometimes cells well defined borders limits seemed to be loosened. In some areas a mucous-fibrin like membrane with variable thickness and extension appeared to partially or totally coat the epithelial surface. Fat drops were present in the intestinal lumen in various samples and a bacterium morphologically resembling bacilli was seen in two occasions. Scanning microscopy confirmed transmission microscopy microvilli findings and also showed little “tufts” of those structures. In addition, it showed an increased number of vacuoles and multivesicular bodies inside various enterocytes, an increased presence of intraepithelial lymphocytes, mitochondrial vacuolization and basement membrane enlargement in the majority of samples analyzed. However, some samples exhibited normal aspect. Conclusions Our study showed the common occurrence of various important intestinal ultrastructural alterations with variable degrees among HIV infected children, some of them in our knowledge not described before.

Assessment of nerve ultrastructure by fibre-optic confocal microscopy.

Science.gov (United States)

Cushway, T R; Lanzetta, M; Cox, G; Trickett, R; Owen, E R

1996-01-01

Fibre-optic technology combined with confocality produces a microscope capable of optical thin sectioning. In this original study, tibial nerves have been stained in a rat model with a vital dye, 4-(4-diethylaminostyryl)-N-methylpyridinium iodide, and analysed by fibre-optic confocal microscopy to produce detailed images of nerve ultrastructure. Schwann cells, nodes of Ranvier and longitudinal myelinated sheaths enclosing axons were clearly visible. Single axons appeared as brightly staining longitudinal structures. This allowed easy tracing of multiple signal axons within the nerve tissue. An accurate measurement of internodal lengths was easily accomplished. This technique is comparable to current histological techniques, but does not require biopsy, thin sectioning or tissue fixing. This study offers a standard for further in vivo microscopy, including the possibility of monitoring the progression of nerve regeneration following microsurgical neurorraphy.

A new nidovirus (NamDinh virus NDiV): Its ultrastructural characterization in the C6/36 mosquito cell line

Energy Technology Data Exchange (ETDEWEB)

Thuy, Nguyen Thanh, E-mail: ngtthuy02@yahoo.com [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Huy, Tran Quang, E-mail: huytq@nihe.org.vn [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Nga, Phan Thi [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Morita, Kouichi [Department of Virology, Institute of Tropical Medicine, Global COE Program, Nagasaki University, Nagasaki (Japan); Dunia, Irene; Benedetti, Lucio [Institut Jacques Monod, UMR7592 Université Paris Diderot/CNRS, Paris (France)

2013-09-15

We describe the ultrastructure of the NamDinh virus (NDiV), a new member of the order Nidovirales grown in the C6/36 mosquito cell line. Uninfected and NDiV-infected cells were investigated by electron microscopy 24–48 h after infection. The results show that the viral nucleocapsid-like particles form clusters concentrated in the vacuoles, the endoplasmic reticulum, and are scattered in the cytoplasm. Mature virions of NDiV were released as budding particles on the cell surface where viral components appear to lie beneath and along the plasma membrane. Free homogeneous virus particles were obtained by ultracentrifugation on sucrose gradients of culture fluids. The size of the round-shaped particles with a complete internal structure was 80 nm in diameter. This is the first study to provide information on the morphogenesis and ultrastructure of the first insect nidovirus NDiV, a missing evolutionary link in the emergence of the viruses with the largest RNA genomes. - Highlights: • NamDinh virus (NDiV), a new member of the order Nidovirales was tested in cultured cell line. • The morphogenesis and ultrastructure of NDiV were investigated by electron microscopy. • The viral nucleocapsid-like particles clustered and scattered in the cytoplasm. • NDiVs were released as budding particles on the cell surface. • The size of the viral particles with a complete internal structure was 80 nm in diameter.

Morphology and Ultrastructure of Multiple Life Cycle Stages of the Photosynthetic Relative of Apicomplexa, Chromera velia

Czech Academy of Sciences Publication Activity Database

Oborník, Miroslav; Vancová, Marie; Lai, De Hua; Janouškovec, J.; Keeling, P. J.; Lukeš, Julius

2011-01-01

Roč. 162, č. 1 (2011), s. 115-130 ISSN 1434-4610 R&D Projects: GA AV ČR IAA601410907; GA MŠk 2B06129; GA MŠk LC07032 Institutional research plan: CEZ:AV0Z60220518 Keywords : Chromera * Apicomplexa * Colpodella * dinoflagellate * phylogeny * ultrastructure Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.136, year: 2011

Ultrastructural investigations of meiosis as a tool in assessing radiation damage in man

Energy Technology Data Exchange (ETDEWEB)

Bojko, M.

1985-01-01

Part I is an introduction to the problems of assessing the short-term effects of ionizing radiation on human meiosis. Part II is an investigation of the ultrastructure of human oocytes at pachytene and diplotene stages of meiotic prophase. Processes leading to crossing over and chiasma formation in the female are compared with those in the male and in other organisms. Part III is a study of short-term effects of ..gamma.. radiation on spermatocytes in larvae of the silk moth, Bombyx mori.

Ultrastructure of the extracellular matrix of bovine dura mater, optic nerve sheath and sclera.

OpenAIRE

Raspanti, M; Marchini, M; Della Pasqua, V; Strocchi, R; Ruggeri, A

1992-01-01

The sclera, the outermost sheath of the optic nerve and the dura mater have been investigated histologically and ultrastructurally. Although these tissues appear very similar under the light microscope, being dense connective tissues mainly composed of collagen bundles and a limited amount of cells and elastic fibres, they exhibit subtle differences on electron microscopy. In the dura and sclera collagen appears in the form of large, nonuniform fibrils, similar to those commonly found in tend...

ARG3.1/ARC expression in hippocampal dentate gyrus astrocytes: ultrastructural evidence and co-localization with glial fibrillary acidic protein

Czech Academy of Sciences Publication Activity Database

Rodríguez, J.J.; Davies, H.A.; Errington, M.L.; Verkhratsky, Alexei; Bliss, T.V.P.; Stewart, M.G.

2008-01-01

Roč. 12, č. 2 (2008), s. 671-678 ISSN 1582-1838 Institutional research plan: CEZ:AV0Z50390512 Keywords : Hippocampus * Ultrastructure * Glia Subject RIV: FH - Neurology Impact factor: 5.114, year: 2008

Life-cycle, ultrastructure, and phylogeny of Parvilucifera corolla sp. nov. (Alveolata, Perkinsozoa), a parasitoid of dinoflagellates.

Science.gov (United States)

Reñé, Albert; Alacid, Elisabet; Figueroa, Rosa Isabel; Rodríguez, Francisco; Garcés, Esther

2017-04-01

Recent studies of marine protists have revealed parasites to be key components of marine communities. Here we describe a new species of the parasitoid genus Parvilucifera that was observed infecting the dinoflagellate Durinskia baltica in salt marshes of the Catalan coast (NW Mediterranean). In parallel, the same species was detected after the incubation of seawater from the Canary Islands (Lanzarote, NE Atlantic). The successful isolation of strains from both localities allowed description of the life cycle, ultrastructure, and phylogeny of the species. Its infection mechanism consists of a free-living zoospore that penetrates a dinoflagellate cell. The resulting trophont gradually degrades the dinoflagellate cytoplasm while growing in size. Once the host is consumed, schizogony of the parasitoid yields a sporocyte. After cytokinesis is complete, the newly formed zoospores are released into the environment and are ready to infect new host cells. A distinguishing feature of the species is the radial arrangement of its zoospores around the central area of the sporocyte during their formation. The species shows a close morphological similarity with other species of the genus, including P. infectans, P. sinerae, and P. rostrata. Copyright © 2016 Elsevier GmbH. All rights reserved.

High resolution of heterogeneity among human neutrophil granules: physical, biochemical, and ultrastructural properties of isolated fractions.

Science.gov (United States)

Rice, W G; Kinkade, J M; Parmley, R T

1986-08-01

Previous studies on the fractionation of human neutrophil granules have identified two major populations: myeloperoxidase (MPO)-containing azurophil, or primary, granules and MPO-deficient specific, or secondary, granules. Peripheral blood neutrophils from individual donors were lysed in sucrose-free media by either hypotonic shock or nitrogen cavitation. Using a novel two-gradient Percoll density centrifugation system, the granule-rich postnuclear supernatant was rapidly (ten minutes) and reproducibly resolved into 13 granule fractions (L1 through L8 and H1 through H5). Granule flotation and recentrifugation experiments on both continuous, self-generated and multiple-step gradients using individual and mixed isolated fractions demonstrated that the banding patterns were isopycnic and nonartifactual. Isolated granules were intact based on the findings that biochemical latency of several granule enzymes was greater than 95%, and thin-sectioned electron micrographs demonstrated intact granule profiles. Biochemical analyses of the granule marker proteins MPO, beta-glucuronidase, lysozyme, and lactoferrin indicated that a number of the fractions were related to the major azurophil and specific granule populations. Lactoferrin was found in ten of 13 fractions (L1 through L8, H1 to H2), whereas MPO was found in every fraction. Consistent with these biochemical data, all fractions exhibited varying degrees of heterogeneity based on ultrastructural morphology and cytochemistry, including diaminobenzidine (DAB) reactivity for peroxidase and periodate-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining for complex glycoconjugates. A variable but significant percentage (23% to 70%) of the granules in fractions L1 through L8 and H1 and H2 showed DAB reactivity, while about 90% of the granules in fractions H3 through H5 were peroxidase positive. These results demonstrated that DAB-reactive granules spanned the entire range of granule size and density. Ultrastructural PA

BIOMEX Experiment: Ultrastructural Alterations, Molecular Damage and Survival of the Fungus Cryomyces antarcticus after the Experiment Verification Tests

Science.gov (United States)

Pacelli, Claudia; Selbmann, Laura; Zucconi, Laura; De Vera, Jean-Pierre; Rabbow, Elke; Horneck, Gerda; de la Torre, Rosa; Onofri, Silvano

2017-06-01

The search for traces of extinct or extant life in extraterrestrial environments is one of the main goals for astrobiologists; due to their ability to withstand stress producing conditions, extremophiles are perfect candidates for astrobiological studies. The BIOMEX project aims to test the ability of biomolecules and cell components to preserve their stability under space and Mars-like conditions, while at the same time investigating the survival capability of microorganisms. The experiment has been launched into space and is being exposed on the EXPOSE-R2 payload, outside of the International Space Station (ISS) over a time-span of 1.5 years. Along with a number of other extremophilic microorganisms, the Antarctic cryptoendolithic black fungus Cryomyces antarcticus CCFEE 515 has been included in the experiment. Before launch, dried colonies grown on Lunar and Martian regolith analogues were exposed to vacuum, irradiation and temperature cycles in ground based experiments (EVT1 and EVT2). Cultural and molecular tests revealed that the fungus survived on rock analogues under space and simulated Martian conditions, showing only slight ultra-structural and molecular damage.

Changes in lignocellulosic supramolecular and ultrastructure during dilute acid pretreatment of Populus and switchgrass

International Nuclear Information System (INIS)

Foston, Marcus; Ragauskas, Art J.

2010-01-01

Dilute acid pretreatment (DAP) is commonly employed prior to enzymatic deconstruction of cellulose to increase overall sugar and subsequent ethanol yields from downstream bioconversion processes. Typically optimization of pretreatment is evaluated by determining hemicellulose removal, subsequent reactivity towards enzymatic deconstruction, and recoverable polysaccharide yields. In this study, the affect of DAP on the supramolecular and ultrastructure of lignocellulosic biomass was evaluated. A series of dilute acidic pretreatments, employing ∼0.10-0.20 mol/m 3 H 2 SO 4 at ∼160-180 o C, for varying residence times were conducted on both Populus and switchgrass samples. The untreated and pretreated biomass samples were characterized by carbohydrate and lignin analysis, gel permeation chromatography (GPC) and 13 C cross polarization magic angle spinning (CPMAS) NMR spectroscopy. GPC analysis shows a reduction in the molecular weight of cellulose and change in its polydispersity index (PDI) with increasing residence time, indicating that pretreatment is actually degrading the cellulose chains. 13 C CPMAS and non-linear line-fitting of the C 4 region in the carbon spectrum of the isolated cellulose not only showed that the crystallinity index increases with residence time, but that the lateral fibril dimension (LFD) and lateral fibril aggregate dimension (LFAD) increase as well.

Ultrastructural analysis of bovine oocytes from ovarian follicles with different diametersAnálise ultra-estrutural de oócitos bovinos provenientes de folículos ovarianos com diferentes diâmetros

Directory of Open Access Journals (Sweden)

Cesar Roberto Esper

2011-10-01

Full Text Available In vitro embryo production is an important technique for facilitating the reproduction of animals with high genetic merit. The greatest challenge for the reproducibility of this technique is the quality of the oocyte that is submitted for in vitro maturation. The aim of this work was to evaluate the ultrastructural characteristics of oocytes from follicles of different diameters using transmission electron microscopy. The animals were divided into 2 groups and were given a single i.m. injection of 250 IU FSH (Pluset, Serono, Italy. To synchronize the follicular growth, all follicles > 2 mm were aspirated during the estrous cycle, which was considered day zero (D0. Group 1 (G1; n = 4 received FSH on day 1 (D1, and the 2- to 5-mm follicles were aspirated on day 2 (D2. The animals in group 2 (G2; n = 5 received FSH on day 2 (D2, and their 10- to 15-mm follicles were aspirated on day 5 (D5. After aspiration, the oocytes from both groups were fixed and prepared for ultrastructural analysis. The oocytes analyzed from both groups had similar ultrastructural characteristics. The presence and distribution of organelles in the cytoplasm of the oocytes did not differ between groups, suggesting that, in relation to the ultrastructural characteristics, oocytes from 2 to 5 mm and 10 to 15 mm follicles are similar.A produção in vitro de embriões é uma técnica importante para facilitar a reprodução de animais com elevado mérito genético. O maior desafio para a reprodutibilidade desta técnica é a qualidade do oócito destinado à maturação in vitro. O objetivo deste trabalho foi avaliar as características ultra-estruturais de oócitos provenientes de folículos com diferentes diâmetros por microscopia eletrônica de transmissão. Os animais foram divididos em dois grupos e receberam uma única injeção im de 250 UI de FSH (Pluset, Serono, Itália. Para sincronizar o crescimento folicular, todos os folículos > 2 mm foram aspirados durante o ciclo

The Effect of Spaceflight on the Ultrastructure of the Cerebellum

Science.gov (United States)

Holstein, Gay R.; Martinelli, Giorgio P.

2003-01-01

In weightlessness, astronauts and cosmonauts may experience postural illusions as well as motion sickness symptoms known as the space adaptation syndrome. Upon return to Earth, they have irregularities in posture and balance. The adaptation to microgravity and subsequent re-adaptation to Earth occurs over several days. At the cellular level, a process called neuronal plasticity may mediate this adaptation. The term plasticity refers to the flexibility and modifiability in the architecture and functions of the nervous system. In fact, plastic changes are thought to underlie not just behavioral adaptation, but also the more generalized phenomena of learning and memory. The goal of this experiment was to identify some of the structural alterations that occur in the rat brain during the sensory and motor adaptation to microgravity. One brain region where plasticity has been studied extensively is the cerebellar cortex-a structure thought to be critical for motor control, coordination, the timing of movements, and, most relevant to the present experiment, motor learning. Also, there are direct as well as indirect connections between projections from the gravity-sensing otolith organs and several subregions of the cerebellum. We tested the hypothesis that alterations in the ultrastructural (the structure within the cell) architecture of rat cerebellar cortex occur during the early period of adaptation to microgravity, as the cerebellum adapts to the absence of the usual gravitational inputs. The results show ultrastructural evidence for neuronal plasticity in the central nervous system of adult rats after 24 hours of spaceflight. Qualitative studies conducted on tissue from the cerebellar cortex (specifically, the nodulus of the cerebellum) indicate that ultrastructural signs of plasticity are present in the cerebellar zones that receive input from the gravity-sensing organs in the inner ear (the otoliths). These changes are not observed in this region in cagematched

Changes in Ultrastructure and Sensory Characteristics on Electro-magnetic and Air Blast Freezing of Beef during Frozen Storage

Science.gov (United States)

2015-01-01

The ultrastructure in the beef muscle of the electro-magnetic resonance and air blast freezing during the frozen storage, and the changes in the quality characteristics after thawing were evaluated. The size of ice crystal was small and evenly formed in the initial freezing period, and it showed that the size was increased as the storage period was elapsed (pfreezing showed the size of ice crystal with a lower rate of increase than the air blast freezing during the frozen storage. The thawing loss of beef stored by the electro-magnetic resonance freezing was significantly lower than the air blast freezing during frozen storage (pfreezing was higher than the air blast on 8 month (pfreezing did not show the difference until 4 months, and it showed higher acceptability in comparison with the beef stored by the air blast freezing. Thus, it is considered that the freezing method has an effect on the change in the ultrastructure and quality characteristics of the beef. PMID:26761797

Ultrastructural analysis of volutin-acidocalciumosomes formation in some species of bacteria, spirochetes, yeast and protozoa during morphogenesis and under environment different factors action

International Nuclear Information System (INIS)

Hovnanyan, K.O.; Hovnanyan, M.K.; Navasardyan, L.A.; Trchounian, A.A.

2012-01-01

Ultrastructure organization of volutin granules in some species of bacteria, spirochetes, yeast and protozoa cellular architecture was studied during morphogenesis and under environment different factors action leading to pathological changes. As the result of complex electron microscopic studies of morphogenesis in some species of prokaryotes and eukaryotic organisms the formation of new structures of volutin-acidocal-ciumosomes has been established within cell cytoplasm. In addition, under the ionizing roentgen and irradiation as well as some antibiotics action morphometric changes and changes in optical properties were also shown. Electron microscopic identification of volutin granules changes in structural organization in bacteria, spirochetes, yeast and protozoa might serve as appropriate express-method for visual evaluation of damage and reparation processes during environment

Ultrastructural investigations of meiosis as a tool in assessing radiation damage in man

International Nuclear Information System (INIS)

Bojko, M.

1985-11-01

Part I is an introduction to the problems of assesing the short-term effects of ionizing radiation on human meiosis. Part II is an investigation of the ultrastructure of human oocytes at pachytene and diplotene stages of meiotic prophase. Processes leading to crossing over and chiasma formation in the female are compared with those in the male and in other organisms. Part III is a study of short-term effects of γ radiation on spermatocytes in larvae of the silk moth, Bombyx mori. (eg)

Semi-quantitative ultrastructural analysis of the localization and neuropeptide content of gonadotropin releasing hormone nerve terminals in the median eminence throughout the estrous cycle of the rat.

Science.gov (United States)

Prevot, V; Dutoit, S; Croix, D; Tramu, G; Beauvillain, J C

1998-05-01

The ultrastructural appearance of gonadotropin releasing hormone-immunoreactive elements was studied in the external zone of the median eminence of adult female Wistar rats. On the one hand, the purpose of the study was to determine the distribution of gonadotropin releasing hormone terminals towards the parenchymatous basal lamina at the level of hypothalamo-hypophyseal portal vessels, throughout the estrous cycle. On the other hand, we have semi-quantified the gonadotropin releasing hormone content in nerve terminals or preterminals during this physiological condition. A morphometric study was coupled to a colloidal 15 mn gold postembedding immunocytochemistry procedure. Animals were killed at 09.00 on diestrus II, 0.900, 10.00, 13.00, 17.00 and 18.00 on proestrus and 09.00 on estrus (n = 4-8 rats/group). A preliminary light microscopic study was carried out to identify an antero-posterior part of median eminence strongly immunostained by anti-gonadotropin releasing hormone antibodies but which was, in addition, easily spotted. This last condition was necessary to make a good comparison between each animal. Contacts between gonadotropin releasing hormone nerve terminals and the basal lamina were observed only the day of proestrus. Such contacts, however, were rare and in the great majority of cases, gonadotropin releasing hormone terminals are separated from basal lamina by tanycytic end feet. The morphometric analysis showed no significant variation in average distance between gonadotropin releasing hormone terminals and capillaries throughout the estrous cycle. Consequently, it did not appear that a large neuroglial plasticity exists during the estrous cycle. However, the observation of contacts only on proestrus together with some ultrastructural images evoke the possibility of a slight plasticity. The semi-quantitative results show that the content of gonadotropin releasing hormone in the nerve endings presented two peaks on proestrus: one at 09.00 (23 +/- 5

Ultrastructural myocardial changes in seven cats with spontaneous hypertrophic cardiomyopathy

DEFF Research Database (Denmark)

Christiansen, Liselotte Bruun; Prats Gavalda, Clara; Hyttel, Poul

2015-01-01

OBJECTIVES: Hypertrophic cardiomyopathy (HCM) is the most common heart disease in cats and shares clinical and pathological characteristics with human HCM. Little is known about the pathogenic mechanisms underlying development of spontaneous feline HCM. ANIMALS: The study population consisted...... of seven cats diagnosed with HCM and eight age-matched cats with no evidence of cardiac disease. METHODS: Fresh myocardial biopsies taken from the middle of the left ventricular posterior free wall were obtained and examined with transmission electron microscopy. RESULTS: Electron microscopic examination...... showed ultrastructural aberrations of the myocardial cytoarchitecture and of the interstitium in the seven cats with HCM. In the most severely affected cats the myofibrils were disorganized and subsarcolemmal mitochondria were depleted. In control cats, contraction band artifacts were commonly seen...

Congenital dyserythropoiesis with intererythroblastic chromatin bridges and ultrastructurally-normal erythroblast heterochromatin: a new disorder.

Science.gov (United States)

Wickramasinghe, S N; Spearing, R L; Hill, G R

1998-12-01

Two non-anaemic subjects, a father and daughter, with a new form of congenital dyserythropoiesis are reported. The features of their disorder are: (1) an abnormal blood film with basophilic stippling of red cells and oval macrocytes, (2) various dysplastic changes in the erythroblasts, including internuclear chromatin bridges, (3) ultrastructurally-normal erythroblast heterochromatin, (4) normal serum thymidine kinase activity, and (5) a probable autosomal dominant inheritance. The last three features distinguish this disorder from CDA type I.

Ultrastructural characteristics of type A epithelioid cells during BCG-granulomatosis and treatment with lysosomotropic isoniazid.

Science.gov (United States)

Shkurupii, V A; Kozyaev, M A; Nadeev, A P

2006-04-01

We studied BCG-granulomas, their cellular composition, and ultrastructure of type A epithelioid cells in the liver of male BALB/c mice with spontaneous granulomatous inflammation. The animals received free isoniazid or isoniazid conjugated with lysosomotropic intracellularly prolonged matrix (dialdehyde dextran, molecular weight 65-75 kDa). Lysosomotropic isoniazid was accumulated in the vacuolar apparatus of epithelioid cells and produced a stimulatory effect on plastic processes in these cells.

Responses of photosynthetic properties and chloroplast ultrastructure of Bryum argenteum from a desert biological soil crust to elevated ultraviolet-B radiation.

Science.gov (United States)

Hui, Rong; Li, Xinrong; Chen, Cuiyun; Zhao, Xin; Jia, Rongliang; Liu, Lichao; Wei, Yongping

2013-04-01

Our understanding of plant responses to enhanced ultraviolet-B (UV-B) radiation has improved over recent decades. However, research on cryptogams is scarce and it remains controversial whether UV-B radiation causes changes in physiology related to photosynthesis. To investigate the effects of supplementary UV-B radiation on photosynthesis and chloroplast ultrastructure in Bryum argenteum Hedw., specimens were cultured for 10 days under four UV-B treatments (2.75, 3.08, 3.25 and 3.41 W m(-2) ), simulating depletion of 0% (control), 6%, 9% and 12% of stratospheric ozone at the latitude of Shapotou, a temperate desert area of northwest China. Analyses showed malondialdehyde content significantly increased, whereas chlorophyll (Chl) fluorescence parameters and Chl contents decreased with increased UV-B intensity. These results corresponded with changes in thylakoid protein complexes and chloroplast ultrastructure. Overall, enhanced UV-B radiation leads to significant decreases in photosynthetic function and serious destruction of the chloroplast ultrastructure of B. argenteum. The degree of negative influences increased with the intensity of UV-B radiation. These results may not only provide a potential mechanism for supplemental UV-B effects on photosynthesis of moss crust, but also establish a theoretical basis for further studies of adaptation and response mechanisms of desert ecosystems under future ozone depletion. Copyright © Physiologia Plantarum 2012.

Ultrastructure of cells of Ulmus americana cultured in vitro and exposed to the culture filtrate of Ceratocystis ulmi

Science.gov (United States)

Paula M. Pijut; R. Daniel Lineberger; Subhash C. Domir; Jann M. Ichida; Charles R. Krause

1990-01-01

Calli of American elm susceptible and resistant to Dutch elm disease were exposed to a culture filtrate of a pathogenic isolate of Ceratocystis ulmi. Cells from untreated tissue exhibited typical internal composition associated with healthy, actively growing cells. All cells exposed to culture filtrate showed appreciable ultrastructural changes....

Ultrastructure of the midgut endocrine cells in Melipona quadrifasciata anthidioides (Hymenoptera, Apidae

Directory of Open Access Journals (Sweden)

C. A. Neves

Full Text Available In this study we describe the ultrastructure of the endocrine cells observed in the midgut of M. quadrifasciata anthidioides. This bee has two types of endocrine cells, which are numerous on the posterior midgut region. Cells of the closed type are smaller and have irregular secretory granules with lower electrondensity than those of the open cell type. The open cell type has elongated mitochondria mainly on the basal area, where most of the secretory granules are also found. Besides the secretion granules and mitochondria, endocrine cells in this species have well-developed autophagic vacuoles and Golgi complex elements.

Lack of correlation between immunologic markers and cell surface ultrastructure in the leukemic phase of lymphoproliferative diseases

Energy Technology Data Exchange (ETDEWEB)

Golomb, Harvey M.; Simon, Deberah

1977-01-01

In a prospective study of malignant cells from 13 patients with the leukemic phase of lymphoproliferative diseases, we wished to determine whether any correlation between the immunologic markers and the cell surface ultrastructure. Five patients had chronic lymphocytic leukemia, four had malignant lymphomas, poorly differentiated lymphocytic type, two had the Sezary syndrome, and one each had acute prolymphocytic leukemia and acute lymphocytic leukemia. Cell separation and isolation was done at room temperature for all specimens. Immunologic markers tested for were surface immunoglobins, a B-cell property, and E-rosettes, a T-cell property. Three patients had T-cell diseases, 6 had B-cell diseases, and 4 were classified as ''null.'' All but one patient had moderate to large numbers of microvilli on their malignant cells. The single exception had a typical B-cell form of chronic lymphocytic leukemia. There appears to be no correlation between immunologic markers and cell surface ultrastructure; therefore, SEM appears not to be valuable in the diagnosis or classification of immunologic sub-types of certain lymphoproliferative diseases.

X-ray scattering evaluation of ultrastructural changes in human dental tissues with thermal treatment.

Science.gov (United States)

Sandholzer, Michael A; Sui, Tan; Korsunsky, Alexander M; Walmsley, Anthony Damien; Lumley, Philip J; Landini, Gabriel

2014-05-01

Micro- and ultrastructural analysis of burned skeletal remains is crucial for obtaining a reliable estimation of cremation temperature. Earlier studies mainly focused on heat-induced changes in bone tissue, while this study extends this research to human dental tissues using a novel quantitative analytical approach. Twelve tooth sections were burned at 400-900°C (30-min exposure, increments of 100°C). Subsequent combined small- and wide-angle X-ray scattering (SAXS/WAXS) experiments were performed at the Diamond Light Source synchrotron facility, where 28 scattering patterns were collected within each tooth section. In comparison with the control sample, an increase in mean crystal thickness was found in burned dentine (2.8-fold) and enamel (1.4-fold), however at a smaller rate than reported earlier for bone tissue (5-10.7-fold). The results provide a structural reference for traditional X-ray scattering methods and emphasize the need to investigate bone and dental tissues separately to obtain a reliable estimation of cremation temperature. © 2014 American Academy of Forensic Sciences.

Serial section scanning electron microscopy (S3EM) on silicon wafers for ultra-structural volume imaging of cells and tissues.

Science.gov (United States)

Horstmann, Heinz; Körber, Christoph; Sätzler, Kurt; Aydin, Daniel; Kuner, Thomas

2012-01-01

High resolution, three-dimensional (3D) representations of cellular ultrastructure are essential for structure function studies in all areas of cell biology. While limited subcellular volumes have been routinely examined using serial section transmission electron microscopy (ssTEM), complete ultrastructural reconstructions of large volumes, entire cells or even tissue are difficult to achieve using ssTEM. Here, we introduce a novel approach combining serial sectioning of tissue with scanning electron microscopy (SEM) using a conductive silicon wafer as a support. Ribbons containing hundreds of 35 nm thick sections can be generated and imaged on the wafer at a lateral pixel resolution of 3.7 nm by recording the backscattered electrons with the in-lens detector of the SEM. The resulting electron micrographs are qualitatively comparable to those obtained by conventional TEM. S(3)EM images of the same region of interest in consecutive sections can be used for 3D reconstructions of large structures. We demonstrate the potential of this approach by reconstructing a 31.7 µm(3) volume of a calyx of Held presynaptic terminal. The approach introduced here, Serial Section SEM (S(3)EM), for the first time provides the possibility to obtain 3D ultrastructure of large volumes with high resolution and to selectively and repetitively home in on structures of interest. S(3)EM accelerates process duration, is amenable to full automation and can be implemented with standard instrumentation.

Serial section scanning electron microscopy (S3EM on silicon wafers for ultra-structural volume imaging of cells and tissues.

Directory of Open Access Journals (Sweden)

Heinz Horstmann

Full Text Available High resolution, three-dimensional (3D representations of cellular ultrastructure are essential for structure function studies in all areas of cell biology. While limited subcellular volumes have been routinely examined using serial section transmission electron microscopy (ssTEM, complete ultrastructural reconstructions of large volumes, entire cells or even tissue are difficult to achieve using ssTEM. Here, we introduce a novel approach combining serial sectioning of tissue with scanning electron microscopy (SEM using a conductive silicon wafer as a support. Ribbons containing hundreds of 35 nm thick sections can be generated and imaged on the wafer at a lateral pixel resolution of 3.7 nm by recording the backscattered electrons with the in-lens detector of the SEM. The resulting electron micrographs are qualitatively comparable to those obtained by conventional TEM. S(3EM images of the same region of interest in consecutive sections can be used for 3D reconstructions of large structures. We demonstrate the potential of this approach by reconstructing a 31.7 µm(3 volume of a calyx of Held presynaptic terminal. The approach introduced here, Serial Section SEM (S(3EM, for the first time provides the possibility to obtain 3D ultrastructure of large volumes with high resolution and to selectively and repetitively home in on structures of interest. S(3EM accelerates process duration, is amenable to full automation and can be implemented with standard instrumentation.

The Protective Effect of Proponyl-L-Carnitine Against Ultrastructural Alterations in Cardiac Muscle of Irradiated and / or diabetic Rats

International Nuclear Information System (INIS)

Abu Nour, S.M.; Abdel-Azeem, M.G.; El-Nashar, D.E.M.

2011-01-01

Heart dysfunction in chronic diabetes has been observed to be associated with depressed myofibrillar adenosine triphosphatase activities. Oxidative stress a factor implicated in the heart injury may contribute towards some of these alterations. The present study was designed to evaluate the efficacy of L-carnitine on gamma radiation and diabetes induced oxidative damage in the heart by investigating alterations in the ultrastructural level. Streptozotocin was intraperitoneally injected (i.p) to rats at a dose of 28 mg/Kg b.wt / day for 2 weeks pre-irradiation. In irradiated groups, animals were exposed to 6.5 Gy whole body gamma radiation. L-carnitine was intraperitoneally injected (i.p) to rats at a dose of 250 mg/Kg b.wt/day for 2 weeks pre-irradiation. Animals were sacrificed on the 7th day after irradiation. The results demonstrated that the whole body exposure of rats to ionizing radiation induce oxidative stress which showed alterations on the ultrastructural level included dis organization with mayofibrillolysis relatively intact z-band (Z), fibrosis, swollen mitochondria, apoptotic nuclei and thickened walls of capillaries. In diabetic rats cardio muscle focal loss of myofilaments, also swelling of mitochondria and rupture of sacroplasmic reticulum, apoptotic nuclei with dilation of capillaries were evident. Administration of L-carnitine pre-irradiation has improved the ultrastructural alterations of the heart tissue. It is proposed that the oxidative stress is associated with a deficit in the status of the antioxidant defense system which may play a critical role in subcellular remodeling, calcium-handling abnormalities and subsequent diabetic cardiomyopathy

Ultrastructural changes in the mycelium of Hericium erinaceum (Bull.; Fr.) Pers. under selenium-induced oxidative stress.

Science.gov (United States)

Ślusarczyk, Joanna; Kuraś, Mieczysław; Malinowska, Eliza; Skalicka-Woźniak, Krystyna; Głowniak, Kazimierz

2014-10-01

In this study we examined the influence of various forms of selenium (organic and inorganic) on the vivacity of Hericium erinaceum mycelium and structural changes and ultrastructure occurring during its development in submerged culture. The mycelium was grown on sodium selenite (Na₂SeO₃), Selol (with 20 and 50 g kg⁻¹ Se, respectively) and a mixture of Na₂SeO₃ and Selol. Samples of the mycelium were collected on day 3 and day 24 of the incubation and viewed under an electron microscope. Selol at concentration 20 g kg⁻¹ did not cause any damage to the cell ultrastructure, but it contributed to the thickening of the cell wall, which implied an influence on polysaccharide production. In the other cases, degradation changes appeared in the protoplasm and the thickness of the cell wall did not increase. The nature of the effect exerted by various sources of selenium in the culture medium on the formation of polysaccharides probably results from the differences in their chemical composition and differences in the toxicity of these compounds towards the cells, but is also connected with the decomposition of the wall surrounding degraded fungal cells. © 2014 Society of Chemical Industry.

Ultrastructural aspects of the oesophageal and reproductive systems of the equine parasite Strongylus vulgaris.

Science.gov (United States)

Mobarak, M S; Ryan, M F

2002-06-01

The ultrastructure of the dorsal oesophageal gland ampulla and its relationship with the oesophagus, oesophageal ultrastructure, and control mechanisms in oesophageal activity were studied. Terminal ducts of the sub-ventral glands open through the oesophageal crown at the base of the buccal cavity. The terminal duct of the dorsal oesophageal gland running through the dorsal gutter opens to the exterior at the rim 'groove' of the buccal capsule. The posterior oesophageal region is clavate and the cuticle of the lumen folds to form outlet valves, 'valvulae'. An inconspicuous oesophago-intestinal valve (three lobes) connects oesophagus and intestine and is visualized in the open and shut position. In the female reproductive tract, with the exception of the uterus, the cells lie on a thick, irregular (convoluted) basal lamina. The apical plasma membrane of the uterus, and seminal receptacle, extend into the lumen by microvilli-like projections with which spermatozoa make intimate contact. The lumen of the uterus is filled with oocytes, fertilized and unfertilized. Testicular cells have two parts linked by a rachis. Spermatocytes are elongated with a large nucleus, distinct nuclear membrane, and many granules. The apical membrane of the rachis forms long microvilli-like projections with balloon-like tips. The amoeboid spermatozoa contain membrane specializations, a nucleus devoid of a membrane, and are enclosed by a pseudopodial-like extension.

Ultrastructure changes in the haemocytes of Galleria mellonella larvae treated with gamma irradiated Steinernema carpocapsae BA2

Directory of Open Access Journals (Sweden)

Hedayat-allah M. Salem

2014-01-01

Full Text Available The ultrastructure studies on the haemolymph of 5th larval instar of Galleria mellonella showed five types of haemocytes; Prohaemocytes, Plasmatocytes, Granulocytes, Oenocytoids and Spherulocytes. After treatment with Steinernema carpocapsae BA2, the haemocytes underwent considerable structural changes. More destructive effects were observed in the haemocytes of G. mellonella treated with gamma irradiated S. carpocapsae.

Ultrastructural and ERG findings in progressive rod-cone dystrophy in a litter of Labrador retrievers.

Science.gov (United States)

Raitta, C; Kommonen, B; Ulshafer, R; Karhunen, U

1991-02-01

Early ultrastructural findings of a progressive photoreceptor dystrophy and corresponding ERG findings are reported in 3 Labrador Retrievers from a litter of 7 pups bred from 2 dogs clinically and electroretinographically affected with generalized progressive retinal dystrophy. The pups were euthanized at 5, 11 and 15 months post partum. The most prominent ultrastructural finding was photoreceptor dystrophy. At 5 months the outer nuclear layer (ONL) consisted of 8-10 layers and seemed reduced in thickness, pyknotic nuclei were seen in this layer. The receptor outer segments (OS) were short and swollen. Some disorientation of OS discs occurred. In the 11-months specimen 7-8 ONL layers were identified. Overall thinning of the neuro-retina had occurred and fewer receptors compared to the 5-months specimen were present. By 15 months the ONL was further reduced to about 4 layers. Enlarged internuclear spaces were present in the ONL as well as around inner segments (IS). Phagocytic cells were frequent among remains of OS. The pigment epithelium appeared normal. The dark adapted ERG b-wave amplitudes and photopic 30 Hz flicker responses were low in comparison to controls of the same breed, and decreased with age. The condition represents a progressive rod-cone dystrophy which shares similarities with primary receptor dystrophy in man such as retinitis pigmentosa.

Anatomical characterization of ultra-structures, biominerals and histolocalization of metabolites in leaves of Genipa americana

Directory of Open Access Journals (Sweden)

Alex L. Vasconcelos

Full Text Available Abstract Inserted in one of the largest families among the Angiosperms, Genipa americana L., Rubiaceae, can be found in all Brazilian territory, presenting great medicinal importance, where several uses have been attributed. In view of this, this work has the purpose of analyzing the ultrastructural, biomineral, phytochemical and histochemical characteristics of the leaves of this native species from Brazil. For this, light microscopy, polarization and scanning electron microscopy techniques were used with X-ray scattering energy, associated to chromatographic and histochemical tests. The anatomical ultrastructural characteristics of the leaves detailed information about the type and arrangement of the cuticle, trichomes, surface and arrangement of the tissues that determine the botanical identity of this species. The phytochemical tests allowed determining their chromatographic pattern and histochemistry to determine the exact storage site of these substances in the leaf. It was observed that the characterization of the crystalline macro-pattern present in the analyzed species, as well as its exact elemental composition, can be considered an important differential diagnosis factor. The results characterize the leaves of this species in different aspects, being a native species and pharmacologically promising, with different popular uses and proven pharmacological activities, and more in depth studies is needed.

Ultrastructural aspects in perithecia hyphae septal pores of Glomerella cingulata F. SP. Phaseoli

Directory of Open Access Journals (Sweden)

Roca M. María Gabriela

2000-01-01

Full Text Available Glomerella cingulata (Stonem. Spauld. & Schrenk f. sp. phaseoli, better known in its anamorphic state Colletotrichum lindemuthianum (Sacc. & Magn. Briosi & Cav., is a causal agent of anthracnose in beans (Phaseolus vulgaris L.. Ultrastructural aspects of the perithecial hyphae of this pathogen were studied. The perithecia hyphae septal pores were found either plugged by a vesicle or unplugged. Some perithecia hyphae septa presented no pore. The Woronin bodies, close to the septal pores, appeared as globose structures which were more electron dense than the occlusions plugging the septal pore.

Transcriptome and proteomic analyses reveal multiple differences associated with chloroplast development in the spaceflight-induced wheat albino mutant mta.

Directory of Open Access Journals (Sweden)

Kui Shi

Full Text Available Chloroplast development is an integral part of plant survival and growth, and occurs in parallel with chlorophyll biosynthesis. However, little is known about the mechanisms underlying chloroplast development in hexaploid wheat. Here, we obtained a spaceflight-induced wheat albino mutant mta. Chloroplast ultra-structural observation showed that chloroplasts of mta exhibit abnormal morphology and distribution compared to wild type. Photosynthetic pigments content was also significantly decreased in mta. Transcriptome and chloroplast proteome profiling of mta and wild type were done to identify differentially expressed genes (DEGs and proteins (DEPs, respectively. In total 4,588 DEGs including 1,980 up- and 2,608 down-regulated, and 48 chloroplast DEPs including 15 up- and 33 down-regulated were identified in mta. Classification of DEGs revealed that most were involved in chloroplast development, chlorophyll biosynthesis, or photosynthesis. Besides, transcription factors such as PIF3, GLK and MYB which might participate in those pathways were also identified. The correlation analysis between DEGs and DEPs revealed that the transcript-to-protein in abundance was functioned into photosynthesis and chloroplast relevant groups. Real time qPCR analysis validated that the expression level of genes encoding photosynthetic proteins was significantly decreased in mta. Together, our results suggest that the molecular mechanism for albino leaf color formation in mta is a thoroughly regulated and complicated process. The combined analysis of transcriptome and proteome afford comprehensive information for further research on chloroplast development mechanism in wheat. And spaceflight provides a potential means for mutagenesis in crop breeding.

[Structure and ultrastructure of the ovary of Cichlasoma urophthalmus (Osteichthyes: Cichlidae)].

Science.gov (United States)

Viedma, Rubí; Franco, Jonathan; Bedia, Carlos; Guedea Fernández, Guadalupe; Villa Zevallos, Héctor Barrera; Barrera Escorcia, Héctor

2011-06-01

The study of the normal development, differentiation, structure and function of various components of developing follicles in the ovaries of numerous fish species have been a consistent focus of comparative reproduction. The structural and ultrastructural features of gonads from Cichlasoma urophthalmus have received scarce attention. In this work, we realized a descriptive study of female gonads of Cichlasoma urophthalmus. A total of 40 samples were collected in the Veracruz Alvarado Lagoon, Mexico in 2007-2008 period including the windy, dry and rainy seasons. Female gonads were extracted and a portion was fixed in 4% formaldehyde for treatment for routine histology hematoxylin and eosin (HE) and another part was processed for transmission electron microscopy (TEM). The gonads were fixed in 3% glutaraldehyde and 2% osmium tetroxide, followed by dehydrated in ethanol 50%, 70%, 80%, 95% and 100% for inclusion in Epon, thin sections were then prepared and were contrasted with lead citrate and uranyl acetate. The process of oocyte development can be divided into five distinct stages (formation of oocytes from oogonia, primary growth, lipid stage, vitellogenesis and maturation). In this work, we found that the primary growth stage is characterized by intense RNA synthesis and the differentiation of the vitelline envelope. Secondary growth starts with the accumulation of lipid droplets in the oocyte cytoplasm (lipid stage), which is then followed by massive uptake and processing of proteins into yolk platelets (vitellogenic stage). During the maturation stage, the lipid inclusions coalesce into a single oil droplet, and hydrolysis of the yolk platelets leads to the formation of a homogeneous mass of fluid yolk in mature eggs. In conclusion, further studies should elucidate structure and ultrastructural changes in the ovarian follicular components, in C. urophthalmus during different stages of oocyte growth.

Ultrastructural and chemotaxonomic analysis of a xylanolytic strain of Cryptococcus adeliensis isolated from sheep droppings in Spain.

Science.gov (United States)

Velázquez, Encarna; del Villar, María; Grondona, Isabel; Monte, Enrique; González-Villa, Tomás

2006-09-01

Cryptococcus adeliensis was initially described as a psycrophilic species containing a single strain CBS 8351(T) isolated from decayed algae in Terre Adelie (Antartida). Later, a second strain of this species was isolated from an immunosuppressed patient affected by leukaemia in Germany and recently several strains from this species have been found in human patients and pigeon droppings of the same country. In this study, we isolated from sheep droppings in Spain a xylanolytic strain named LEVX01 that was phenotypically related to the strain CBS 8351(T) and showed a 100% similarity in the D1/D2 domain and 5.8S-ITS region sequences with respect to the remaining described strains of C. adeliensis. These findings suggest that this species has a wide geographical distribution and that the animal faeces are a common habitat for C. adeliensis. The chemotaxonomic analyses showed the absence of detectable amounts of xylose in the cell walls of the strains LEVX01 and CBS8351(T) in contrast to other Cryptococcus species. Interestingly, the ultrastructural study showed the presence of fimbriae in these two strains that could be involved in the attachment to the host cells and, as occurs in Candida albicans, they could also be a pathogenicity factor for the man.

The ultrastructure of protein bodies isolated from Pisum sativum and Iris pseudoacorus L. seeds

Directory of Open Access Journals (Sweden)

Barbara Gabara

2015-01-01

Full Text Available Protein bodies of Pisum sativum and Iris pseudoacorus seeds have been isolated in sucrose gradient with addition of 50mM citrate buffer, pH 5. Their ultrastructure due to isolation procedure has been described. Two types of protein bodies are present in pea and iris seeds: simple and compex ones - with many inclusions. The method of isolation, used in this paper extracts partly proteins - probably albumins, and also substances present in globoids i.e. phytin and acid phosphatase.

Ultrastructure and Glycoconjugate Pattern of the Foot Epithelium of the Abalone Haliotis tuberculata (Linnaeus, 1758 (Gastropoda, Haliotidae

Directory of Open Access Journals (Sweden)

I. Bravo Portela

2012-01-01

Full Text Available The foot epithelium of the gastropod Haliotis tuberculata is studied by light and electron microscopy in order to contribute to the understanding of the anatomy and functional morphology of the mollusks integument. Study of the external surface by scanning electron microscopy reveals that the side foot epithelium is characterized by a microvillus border with a very scant presence of small ciliary tufts, but the sole foot epithelium bears a dense field of long cilia. Ultrastructural examination by transmission electron microscopy of the side epithelial cells shows deeply pigmented cells with high electron-dense granular content which are not observed in the epithelial sole cells. Along the pedal epithelium, seven types of secretory cells are present; furthermore, two types of subepithelial glands are located just in the sole foot. The presence and composition of glycoconjugates in the secretory cells and subepithelial glands are analyzed by conventional and lectin histochemistry. Subepithelial glands contain mainly N-glycoproteins rich in fucose and mannose whereas secretory cells present mostly acidic sulphated glycoconjugates such as glycosaminoglycans and mucins, which are rich in galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine. No sialic acid is present in the foot epithelium.

Ultrastructure of the wild rice Oryza grandiglumis (Gramineae in Costa Rica

Directory of Open Access Journals (Sweden)

Ethel Sánchez

2006-06-01

Full Text Available Oryza grandiglumis is a wild species of rice endemic to tropical America. This species was first found in 1998 in the wetlands of Caño Negro, located in the northern part of Costa Rica. Twenty five plants of O. grandiglumis were processed for scanning electron microscope. An ultrastructural description of the leaf blade, ligule, auricles, spikelet and caryopsis, with an emphasis on structures of taxonomic value. The leaf blade has a characteristic cuticular wax pattern, composed of dense rod-like structures, and is surrounded by papillae, zipper- like silica cells, abundant bulky prickle trichomes, and hooked trichomes. The blade’s edge has three rows of hooked prickle trichomes of various sizes. The auricles wrapped the culm, with long attenuated trichomes at the edges; the base was surrounded by oblong cells. The ligule is a blunt membrane covered by short prickle trichomes. Spikelet morphology is characteristic of the Poaceae family, but the sterile lemmas were nearly as long as the fertile lemmas, and they have an unique crown-like structure of lignified spines between the rachilla and the fertile lemmas. Comparison with Brazilian specimens of O. grandiglumis revealed little differences in the ultrastructural characteristics. Rev. Biol. Trop. 54(2: 377-385. Epub 2006 Jun 01.El arroz silvestre Oryza grandiglumis es endémico de América. Se localiza en la zona norte de Costa Rica, principalmente en el humedal de Caño Negro y del Río Medio Queso. Es una planta vigorosa y grande. Su nombre deriva del gran tamaño de las lemas estériles (glumas. Presentamos una descripción ultraestructural de la lámina foliar, lígula, aurículas, espiguilla y cariópside, con énfasis en las estructuras de valor taxonómico, usando el microscopio electrónico de barrido. La lámina foliar se caracteriza por presentar un patrón de cera cuticular en forma de densos bastoncillos. Presenta estomas rodeados de papilas, células de sílice en forma crenada

Ultrastructure of spermatozoa of spider crabs, family Mithracidae (Crustacea, Decapoda, Brachyura): Integrative analyses based on morphological and molecular data.

Science.gov (United States)

Assugeni, Camila de O; Magalhães, Tatiana; Bolaños, Juan A; Tudge, Christopher C; Mantelatto, Fernando L; Zara, Fernando J

2017-12-01

Recent studies based on morphological and molecular data provide a new perspective concerning taxonomic aspects of the brachyuran family Mithracidae. These studies proposed a series of nominal changes and indicated that the family is actually represented by a different number and representatives of genera than previously thought. Here, we provide a comparative description of the ultrastructure of spermatozoa and spermatophores of some species of Mithracidae in a phylogenetic context. The ultrastructure of the spermatozoa and spermatophore was observed by scanning and transmission electron microscopy. The most informative morphological characters analysed were thickness of the operculum, shape of the perforatorial chamber and shape and thickness of the inner acrosomal zone. As a framework, we used a topology based on a phylogenetic analysis using mitochondrial data obtained here and from previous studies. Our results indicate that closely related species share a series of morphological characteristics of the spermatozoa. A thick operculum, for example, is a feature observed in species of the genera Amphithrax, Teleophrys, and Omalacantha in contrast to the slender operculum observed in Mithraculus and Mithrax. Amphithrax and Teleophrys have a rhomboid perforatorial chamber, while Mithraculus, Mithrax, and Omalacantha show a wider, deltoid morphology. Furthermore, our results are in agreement with recently proposed taxonomic changes including the separation of the genera Mithrax (previously Damithrax), Amphithrax (previously Mithrax) and Mithraculus, and the synonymy of Mithrax caribbaeus with Mithrax hispidus. Overall, the spermiotaxonomy of these species of Mithracidae represent a novel set of data that corroborates the most recent taxonomic revision of the family and can be used in future taxonomic and phylogenetic studies within this family. © 2017 Wiley Periodicals, Inc.

Ultrastructural features of the uterus in the sexually immature ostrich (Struthio camelus during periods of ovarian inactivity and activity

Directory of Open Access Journals (Sweden)

M-C. Madekurozwa

2007-09-01

Full Text Available The ultrastructure of the surface epithelium and tubular glands of the uterus in the immature ostrich is described. In ostriches with inactive ovaries the uterus is lined by a non-ciliated simple columnar epithelium, with basally located heterochromatic nuclei. Scanning electron microscopy revealed that these non-ciliated cells have a dense microvillous cover. A simple columnar to pseudostratified columnar epithelium, comprised of non-ciliated and ciliated cells, lines the uterus in birds with active ovaries. The ciliated cells possess a wide luminal region, which contains a nucleus and various organelles. An accumulation of secretory granules was observed in the apical regions of the non-ciliated cells, as well as in a few ciliated cells. In addition to non-ciliated and ciliated cells, a cell type with rarefied cytoplasm was also identified. These cells appear to correspond to calcium secreting cells identified in other avian species. The results of this study indicate that, although uterine differentiation is present in immature ostriches with active ovaries, the production of secretory product appears to occur mainly in non-ciliated epithelial cells.

Experimental white piedra: a robust approach to ultrastructural analysis, scanning electron microscopy and etiological discoveries.

Science.gov (United States)

Inácio, Cicero P; Rocha, Ana Paula S; Barbosa, Renan do N; Oliveira, Neiva T; Silva, Josineide C; de Lima-Neto, Reginaldo G; Macêdo, Danielle Patrícia C; Neves, Rejane P

2016-01-01

White piedra is a fungal infection characterized by nodules comprised of Trichosporon species and restricted to the extrafollicular portion of the hair shaft. The diagnosis is based on clinical and mycological characteristics, and must be confirmed with a precise identification of the etiological agent. This research aimed to develop an in vitro infection model of white piedra and analyze its morphological and ultra-structural aspects. In the process, hair infection was induced using eight isolates of the genus Trichosporon maintained in the Culture Collection Micoteca URM. The ITS and IGS1 regions were sequenced for taxonomic confirmation. Scanning Electron Microscope (SEM) was performed at the Strategic Center for Northeast Technologies (CETENE). The scanning electron microscope was equipped with an Energy Dispersion Spectrometer (EDS). The Trichosporon isolates were identified as Trichosporon asahii (6) and Trichosporon montevideense (2) by internal transcript spacer (ITS) region and intergenic spacer 1 region (IGS1) sequencing. All eight strains were used to induce the in vitro hair infection, and nodules formed after the incubation period. Temperature variations and high humidity were not observed to be related to the development of this hair disease. The main chemical constituents detected in the nodules were carbon, nitrogen and oxygen, as well as a low level of sulfur. The absence of calcium, combined with the low level of sulfur, might explain the soft nature of the white piedra nodules. This study demonstrated that several Trichosporon species may be responsible for causing white piedra. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

III. Cellular ultrastructures in situ as key to understanding tumor energy metabolism: biological significance of the Warburg effect.

Science.gov (United States)

Witkiewicz, Halina; Oh, Phil; Schnitzer, Jan E

2013-01-01

Despite the universality of metabolic pathways, malignant cells were found to have their metabolism reprogrammed to generate energy by glycolysis even under normal oxygen concentrations (the Warburg effect). Therefore, the pathway energetically 18 times less efficient than oxidative phosphorylation was implicated to match increased energy requirements of growing tumors. The paradox was explained by an abnormally high rate of glucose uptake, assuming unlimited availability of substrates for tumor growth in vivo. However, ultrastructural analysis of tumor vasculature morphogenesis showed that the growing tissue regions did not have continuous blood supply and intermittently depended on autophagy for survival. Erythrogenic autophagy, and resulting ATP generation by glycolysis, appeared critical to initiating vasculature formation where it was missing. This study focused on ultrastructural features that reflected metabolic switch from aerobic to anaerobic. Morphological differences between and within different types of cells were evident in tissue sections. In cells undergoing nucleo-cytoplasmic conversion into erythrosomes (erythrogenesis), gradual changes led to replacing mitochondria with peroxisomes, through an intermediate form connected to endoplasmic reticulum. Those findings related to the issue of peroxisome biogenesis and to the phenomenon of hemogenic endothelium. Mitochondria were compacted also during mitosis. In vivo, cells that lost and others that retained capability to use oxygen coexisted side-by-side; both types were important for vasculature morphogenesis and tissue growth. Once passable, the new vasculature segment could deliver external oxygen and nutrients. Nutritional and redox status of microenvironment had similar effect on metabolism of malignant and non-malignant cells demonstrating the necessity to maintain structure-energy equivalence in all living cells. The role of glycolysis in initiating vasculature formation, and in progression of

Ultrastructural apoptotic lesions induced in rat thymocytes after borax ingestion.

Science.gov (United States)

Sylvain, I C; Berry, J P; Galle, P

1998-01-01

Apoptosis has gained increasing attention in recent years. Several chemical compounds induce apoptotic lesions in the thymus. Male Wistar rats received 2000 ppm of borax (Na2B4O7.10H2O) in their food for 16 days. The rats were sacrificed 2, 5, 9, 12, 19, 21, 26 and 28 days after the beginning of treatment. Thymus samples of all rats were taken. A Philips EM 300 electron microscopy was used to study the ultrastructural morphology. Serious nuclear and cytoplasmic lesions were observed. Moreover, numerous macrophages containing apoptotic cells were present in the thymus. The alterations were observed from the 2nd to the 28th day. The extent of damage was much more important in the rats sacrificed 21, 26 and 28 days after borax ingestion.

Effects of soft x-ray irradiation on cell ultrastructure

International Nuclear Information System (INIS)

Ford, T.W.; Page, A.M.; Stead, A.D.; Foster, G.F.

1993-01-01

The future of X-ray microscopy lies mainly in its potential for imaging fresh, hydrated biological material at a resolution superior to that of light microscopy. For the image to be accepted as representing the cellular organization of the living cell, it is essential that artifacts are not introduced as a result of the image collection system. One possible source of artifacts is cellular damage resulting from the irradiation of the material with soft X-rays. Cells of the unicellular alga Chlorella have been examined by transmission electron microscopy (TEM) following exposure to different doses of monochromatic (380eV) soft X-rays. Extreme ultrastructural damage has been detected following doses of 10 3 -10 4 Gy, in particular loss of cellular membranes such as the internal thylakoid membranes of the chloroplast. This is discussed in relation to dosage commonly used for imaging by soft X-ray microscopy

Ultrastructure of the harmful unarmored dinoflagellate Cochlodinium polykrikoides (Dinophyceae) with reference to the apical groove and flagellar apparatus

DEFF Research Database (Denmark)

Iwataki, Mitsunori; Hansen, Gert; Moestrup, Øjvind

2010-01-01

The external and internal ultrastructure of the harmful unarmored dinoflagellate Cochlodinium polykrikoides Margalef has been examined with special reference to the apical groove and three-dimensional structure of the flagellar apparatus. The apical groove is U-shaped and connected to the anterior...

The ultrastructural changes in the liver cells induced by high doses of Benzodiazepine Tranquilizing drugs: An experimental transmission electron microscopic study on male guinea pigs

International Nuclear Information System (INIS)

Bisher, Ameen S. Ahmad

2008-01-01

Benzodiazepines are tranquilizing psychotropic drugs. Unfortunately, despite their therapeutic benefits, they are illegally consumed in high doses by some addicts to reach a sedative, exhilarative and euphoria state similar to that produced by narcotic substances. The present study, using transmission electron microscope on male guinea pigs, aims to investigate the potential ultrastructural changes in the liver cells induced by the high doses of Benzodiazepines. Animals in three treated groups administrated a daily combined dose consisted of (10mg Alprazolam with 10mg Diazepam/day/animal) for three different treatment periods: 7, 15, and 25 days. The ultrastructural examination of the hepatocytes of the animals treated for 15 days showed limited changes in the form of marginal heterochromatine accompanied with marginal nucleoli enlargement. On the other hand, severe ultrastructural damages are observed in the animals treated for 25 days, which appeared in the following various patterns: fatty degeneration of the hepatocytes as indicated by the accumulation of large number of lipid droplets in the cytoplasm, marked nuclear atrophy in some necrotic hepatocytes, massive nuclear degeneration in other hepatocytes, mitochondrial damages in the form of cristea destruction accompanied with abnormal oval shape, massive lysis of the cytoplasmic organelles with severe plasma membrane rupture. In conclusion, the observed ultrastructural damages in the present study may refer to the potential hepatotoxic effects of the high dose of Benzodiazepins. It is recommended that much more official restrictions should be applied on the pharmacies sector to prevent any illegal selling of these drugs in order to prevent abusers from obtaining them, as unfortunately in some developing countries the illegal selling of these drugs is known to occur due to the absence of official control. (author)

Anatomy and ultrastructure alterations of Leucaena leucocephala (Lam.) inoculated with mycorrhizal fungi in response to arsenic-contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Schneider, Jerusa, E-mail: jerusaschneider@hotmail.com [Departamento de Ciência do Solo, Universidade Federal de Lavras (UFLA), PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil); Labory, Claudia Regina Gontijo [Departamento de Fitopatologia, Universidade Federal de Lavras, PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil); Rangel, Wesley Melo [Departamento de Ciência do Solo, Universidade Federal de Lavras (UFLA), PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil); Alves, Eduardo [Departamento de Fitopatologia, Universidade Federal de Lavras, PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil); Guilherme, Luiz Roberto Guimarães [Departamento de Ciência do Solo, Universidade Federal de Lavras (UFLA), PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil)

2013-11-15

Highlights: ► Inoculation of L. leucocephala improved plant growth in high-As soils. ► Plants inoculated with Glomus clarum were less sensitive to As. ► Ultrastructural changes in leaves of L. leucocephala. ► Modified structures in intracellular spaces in plants inoculated with G. clarum. ► Cell disruption and stacking of root cell walls at high As concentrations. -- Abstract: Many studies demonstrate the potential application of arbuscular mycorrhizal fungi (AMF) for remediation purposes, but little is known on AMF potential to enhance plant tolerance to arsenic (As) and the mechanisms involved in this process. We carried anatomical and ultrastructural studies to examine this symbiotic association and the characteristics of shoots and roots of Leucaena leucocephala in As-amended soils (35 and 75 mg As dm{sup −3}). The experiment used 3 AMF isolates from uncontaminated soils: Acaulospora morrowiae, Glomus clarum, and Gigaspora albida; a mixed inoculum derived from combining these 3 isolates (named Mix AMF); and, 3 AMF isolates from As-contaminated areas: A. morrowiae, G. clarum and Paraglomus occultum. Phytotoxicity symptoms due to arsenic contamination appeared during plant growth, especially in treatments without AMF application. Inoculation with G. clarum and the mixture of species (A. morrowiae, G. albida, and G. clarum) resulted in better growth of L. leucocephala in soils with high As concentrations, as well as significant As removal from the soil, showing a potential for using AMF in phytoextraction. Light microscopy (LS), transmission (TEM) and scanning electron microscopies (SEM) studies showed the colonization of the AMF in plant tissues and damage in all treatments, with ultrastructural changes being observed in leaves and roots of L. leucocephala, especially with the addition of 75 mg dm{sup −3} of As.

The ultrastructure of tumor cells in patients with rectal cancer after pre-operative irradiation and intra-operative cryotherapy

International Nuclear Information System (INIS)

Vyinnik, Yu.O.; Kotenko, O.Je.; Nevzorov, V.P.; Chyibyisov, L.P.

2000-01-01

Electronic microscopy of the tumor cells was performed to confirm the efficacy of combined pre-operative gamma-therapy and intraoperative cryotherapy (CT). Pre-operative irradiation at the dose of 20 Gy accompanied by intra-operative cryotherapy caused the changes in the ultrastructure, the depth and degree of which allow to consider them destructive and irreversible

Responses of photosynthetic properties and chloroplast ultrastructure of two moss crusts from a desert biological soil crust to supplementary UV-B radiation

Science.gov (United States)

Hui, Rong; Li, Xinrong; Zhao, Yang; Pan, Yanxia

2016-04-01

Our understanding of plant responses to supplementary ultraviolet-B (UV-B) radiation due to stratospheric ozone depletion has improved over recent decades. However, research on biological soil crusts (BSCs) is scarce and it remains controversial. Laboratory studies were conducted to investigate the influence of UV-B radiation on the Bryum argenteum and Didymodon vinealis isolated from BSCs, which are both dominant species in moss crusts found within patches of shrubs and herbs in the Tengger Desert of northern China. The aim of the current work was to evaluate whether supplementary UV-B radiation affected photosynthetic properties and chloroplast ultrastructure of two moss crusts and whether response differences were observed between the crusts. Four levels of UV-B radiation of 2.75 (control), 3.08, 3.25, and 3.41 W m-2 was achieved using fluorescence tube systems for 10 days, simulating 0, 6, 9, and 12% of stratospheric ozone at the latitude of Shapotou, respectively. We measured photosynthetic apparatus as assessed by chlorophyll a fluorescence parameters, photosynthetic pigment contents, and observations of chloroplast ultrastructure. Additionally, soluble proteins and UV-B absorbing compounds were simultaneously investigated. The results of this study showed that chlorophyll a fluorescence parameters (i.e., the maximal quantum yield of PSII photochemistry, the effective quantum yield of PSII photochemistry, and photochemical quenching coefficient), photosynthetic pigment contents, soluble protein contents, total flavonoid contents and the ultrastructure were negatively influenced by elevated UV-B radiation and the degree of detrimental effects significantly increased with the intensity of UV-B radiation. Moreover, results demonstrated that the negative effects on photosynthesis and chloroplast ultrastructure were more serious in B. argenteum than that in D. vinealis. These results may not only provide a potential mechanism for supplemental UV-B effects on

EFFECT OF CYCLOSPORINE A ON THE KIDNEY OF RABBIT: A LIGHT AND ULTRASTRUCTURAL STUDY

OpenAIRE

Fathy Ahmed Fetouh; Abdelmonem Awad Hegazy

2014-01-01

Background: Nephrotoxicity is a relatively common problem in patients immunosuppressed with cyclosporine A (CsA) with an incidence reaching up to thirty percent. The present work aimed to study the histological and ultrastructural effects of CsA on the kidney of rabbit. Materials and Methods: Two groups of Egyptian adult rabbits were used for this study (5 rabbits for each). One group was used as a control and the other group (experimental) was treated with CsA in a dose of 15 mg/kg of bod...

Morphological and ultrastructural characteristics of extracellular matrix changes in oral squamous cell carcinoma

Directory of Open Access Journals (Sweden)

Usha Agrawal

2011-01-01

Full Text Available Background: The biology of oral squamous cell carcinoma (OSCC, including its progression from dysplasia to carcinoma, "field effects", genetic changes in tumor associated mucosa (TAM and effect of matrix metalloproteinases in breaking down of matrix proteins to facilitate invasion, has been well documented. However, what remains to be done is to extrapolate this knowledge to improve patient care. Aim: The aim of this study was to observe the extracellular matrix (ECM changes with the routine histochemical stains available to most histopathologists. Materials and Methods: The study includes 72 cases of OSCC in which the tumor and adjacent normal appearing areas were sampled to study the ECM changes with hematoxylin and eosin (H and E and Verhoeff′s-Van Gieson elastic stain (VVG. Results: Basophilic fragmentation of collagen (H and E and clumped short elastic fibers (VVG were seen in 12 (16.7% cases. Of the remaining cases, 18 (25% had a dense lymphocytic infiltrate and had no demonstrable elastic fibers. Those cases with H and E changes were further studied and compared with normal mucosa for ultrastructural changes. The ultrastructural study demonstrated an increase in oxytalan, elaunin and elastic fibers and decrease in collagen fibers with some transformation changes associated with OSCCs and lymph node metastasis. Conclusion: Changes in transformation of collagen to elastic fibers and also the loss of both the fibers in areas of lymphocytic infiltration possibly indicate degradation of ECM fibers by factors released from the lymphocytes or tumor cells and the limiting effect on the tumor by ECM remodeling.

Transcriptome analysis reveals key differentially expressed genes involved in wheat grain development

Directory of Open Access Journals (Sweden)

Yonglong Yu

2016-04-01

Full Text Available Wheat seed development is an important physiological process of seed maturation and directly affects wheat yield and quality. In this study, we performed dynamic transcriptome microarray analysis of an elite Chinese bread wheat cultivar (Jimai 20 during grain development using the GeneChip Wheat Genome Array. Grain morphology and scanning electron microscope observations showed that the period of 11–15 days post-anthesis (DPA was a key stage for the synthesis and accumulation of seed starch. Genome-wide transcriptional profiling and significance analysis of microarrays revealed that the period from 11 to 15 DPA was more important than the 15–20 DPA stage for the synthesis and accumulation of nutritive reserves. Series test of cluster analysis of differential genes revealed five statistically significant gene expression profiles. Gene ontology annotation and enrichment analysis gave further information about differentially expressed genes, and MapMan analysis revealed expression changes within functional groups during seed development. Metabolic pathway network analysis showed that major and minor metabolic pathways regulate one another to ensure regular seed development and nutritive reserve accumulation. We performed gene co-expression network analysis to identify genes that play vital roles in seed development and identified several key genes involved in important metabolic pathways. The transcriptional expression of eight key genes involved in starch and protein synthesis and stress defense was further validated by qRT-PCR. Our results provide new insight into the molecular mechanisms of wheat seed development and the determinants of yield and quality.

Continuation of mitosis after selective laser microbeam destruction of the centriolar region

Energy Technology Data Exchange (ETDEWEB)

Berns, N.W.; Richardson, S.M.

1977-12-01

The centriole regions of prophase PTK2 cells were irradiated with a laser microbeam. Cells continued through mitosis normally. Ultrastructural analysis revealed either an absence of centrioles or severely damaged centrioles at the irradiated poles. Microtubules appeared to focus into pericentriolar cloud material.

Continuation of mitosis after selective laser microbeam destruction of the centriolar region

International Nuclear Information System (INIS)

Berns, N.W.; Richardson, S.M.

1977-01-01

The centriole regions of prophase PTK2 cells were irradiated with a laser microbeam. Cells continued through mitosis normally. Ultrastructural analysis revealed either an absence of centrioles or severely damaged centrioles at the irradiated poles. Microtubules appeared to focus into pericentriolar cloud material

An ultrastructural examination of irradiated, immunizing schistosomula of Schistosoma mansoni during their extended stay in the lungs

International Nuclear Information System (INIS)

Mastin, A.; Wilson, R.A.; Bickle, Q.D.

1985-01-01

An ultrastructural study has been performed on radiation-attenuated parasites fixed in situ during their extended stay in the lungs. At day 7 post-infection all parasites were located within blood vessels. In contrast to normally migrating parasites, at days 13 and 21 post-infection the majority of radiation-attenuated parasites were lying free within alveoli. It appeared that radiation-attenuated parasites had undergone the normal developmental changes associated with the lung-stage of migration. No ultrastructural evidence was found to suggest why schistosomula failed to migrate further and instead burst into alveoli. No parasites observed on day 7 post-infection were associated with a host inflammatory reaction. At day 13, inflammation was noticeable but could have been a response as much to pulmonary tissue damage as to the presence of parasites. At day 21 post-infection some parasites were internally disrupted but were not associated with host inflammatory reactions and had intact tegumental surfaces. One parasite was observed at day 21 with an adherent neutrophil infiltrate and extensive tegumental damage. The relevance of persisting lung-stage parasites to the induction of resistance to challenge is discussed. (author)

Helium ion microscopy and ultra-high-resolution scanning electron microscopy analysis of membrane-extracted cells reveals novel characteristics of the cytoskeleton of Giardia intestinalis.

Science.gov (United States)

Gadelha, Ana Paula Rocha; Benchimol, Marlene; de Souza, Wanderley

2015-06-01

Giardia intestinalis presents a complex microtubular cytoskeleton formed by specialized structures, such as the adhesive disk, four pairs of flagella, the funis and the median body. The ultrastructural organization of the Giardia cytoskeleton has been analyzed using different microscopic techniques, including high-resolution scanning electron microscopy. Recent advances in scanning microscopy technology have opened a new venue for the characterization of cellular structures and include scanning probe microscopy techniques such as ultra-high-resolution scanning electron microscopy (UHRSEM) and helium ion microscopy (HIM). Here, we studied the organization of the cytoskeleton of G. intestinalis trophozoites using UHRSEM and HIM in membrane-extracted cells. The results revealed a number of new cytoskeletal elements associated with the lateral crest and the dorsal surface of the parasite. The fine structure of the banded collar was also observed. The marginal plates were seen linked to a network of filaments, which were continuous with filaments parallel to the main cell axis. Cytoplasmic filaments that supported the internal structures were seen by the first time. Using anti-actin antibody, we observed a labeling in these filamentous structures. Taken together, these data revealed new surface characteristics of the cytoskeleton of G. intestinalis and may contribute to an improved understanding of the structural organization of trophozoites. Copyright © 2015 Elsevier Inc. All rights reserved.

Ultrastructural and physiological responses of potato (Solanum tuberosum L.) plantlets to gradient saline stress

Science.gov (United States)

Gao, Hui-Juan; Yang, Hong-Yu; Bai, Jiang-Ping; Liang, Xin-Yue; Lou, Yan; Zhang, Jun-Lian; Wang, Di; Zhang, Jin-Lin; Niu, Shu-Qi; Chen, Ying-Long

2015-01-01

Salinity is one of the major abiotic stresses that impacts plant growth and reduces the productivity of field crops. Compared to field plants, test tube plantlets offer a direct and fast approach to investigate the mechanism of salt tolerance. Here we examined the ultrastructural and physiological responses of potato (Solanum tuberosum L. c.v. “Longshu No. 3”) plantlets to gradient saline stress (0, 25, 50, 100, and 200 mM NaCl) with two consequent observations (2 and 6 weeks, respectively). The results showed that, with the increase of external NaCl concentration and the duration of treatments, (1) the number of chloroplasts and cell intercellular spaces markedly decreased, (2) cell walls were thickened and even ruptured, (3) mesophyll cells and chloroplasts were gradually damaged to a complete disorganization containing more starch, (4) leaf Na and Cl contents increased while leaf K content decreased, (5) leaf proline content and the activities of catalase (CAT) and superoxide dismutase (SOD) increased significantly, and (6) leaf malondialdehyde (MDA) content increased significantly and stomatal area and chlorophyll content decline were also detected. Severe salt stress (200 mM NaCl) inhibited plantlet growth. These results indicated that potato plantlets adapt to salt stress to some extent through accumulating osmoprotectants, such as proline, increasing the activities of antioxidant enzymes, such as CAT and SOD. The outcomes of this study provide ultrastructural and physiological insights into characterizing potential damages induced by salt stress for selecting salt-tolerant potato cultivars. PMID:25628634

Photosynthetic Characteristics and Chloroplast Ultrastructure of Summer Maize Response to Different Nitrogen Supplies.

Science.gov (United States)

Liu, Zheng; Gao, Jia; Gao, Fei; Liu, Peng; Zhao, Bin; Zhang, Jiwang

2018-01-01

Maize ( Zea mays L.) is the important crop over the world. Nitrogen (N) as necessary element affects photosynthetic characteristics and grain yield of summer maize. In this study, N0 (0 kg N ha -1 ), N1 (129 kg N ha -1 ), N2 (185 kg N ha -1 ), and N3 (300 kg N ha -1 ) was conducted using hybrid 'ZhengDan958' at Dawenkou research field (36°11'N, 117°06'E, 178 m altitude) in the North China Plain to explore the effects of N rate on photosynthetic characteristics and chloroplast ultrastructure. Gas exchange parameters, chlorophyll fluorescence parameters, leaf area index (LAI), chlorophyll SPAD value, chloroplast ultrastructure, dry matter weight and grain yield were measured. At physiological maturity stage, dry matter weight and grain yield of N2 increased by 33-52% ( P ≤ 0.05) and 6-32% ( P ≤ 0.05), respectively, compared with other treatments. During the growing from silking (R1) to milk (R3) stage, LAI of N0 and N1 were 35-38% ( P ≤ 0.05) and 9-23% ( P ≤ 0.05) less than that of N2, respectively. Chlorophyll SPAD value of N0 and N1 were 13-22% ( P ≤ 0.05) and 5-11% ( P ≤ 0.05) lower than that of N2. There was no significant difference in LAI and chlorophyll SPAD value between N2 and N3 during the period from R1 to R3 ( P > 0.05). The net photosynthetic rate ( P n ), maximal quantum efficiency of PSII ( F v / F m ) and quantum efficiency of PSII (Φ PSII ) were higher with the increase of N rate up to N2 ( P ≤ 0.05), and those of N3 were significantly less than N2 ( P ≤ 0.05). In compared with N2, the chloroplast configuration of N0 and N1 became elliptical, almost circular or irregular. The membrane of chloroplast and thylakoid resolved with growing stage, and the number of chloroplast per cell and lamellae per grana decreased under N0 and N1 treatment ( P ≤ 0.05). Under N0 and N1 treatments, summer maize had more negative photosynthetic characteristics. The more number of osmium granule and vesicle and the larger gap between lamellae were

Photosynthetic Characteristics and Chloroplast Ultrastructure of Summer Maize Response to Different Nitrogen Supplies

Directory of Open Access Journals (Sweden)

Zheng Liu

2018-05-01

Full Text Available Maize (Zea mays L. is the important crop over the world. Nitrogen (N as necessary element affects photosynthetic characteristics and grain yield of summer maize. In this study, N0 (0 kg N ha-1, N1 (129 kg N ha-1, N2 (185 kg N ha-1, and N3 (300 kg N ha-1 was conducted using hybrid ‘ZhengDan958’ at Dawenkou research field (36°11′N, 117°06′E, 178 m altitude in the North China Plain to explore the effects of N rate on photosynthetic characteristics and chloroplast ultrastructure. Gas exchange parameters, chlorophyll fluorescence parameters, leaf area index (LAI, chlorophyll SPAD value, chloroplast ultrastructure, dry matter weight and grain yield were measured. At physiological maturity stage, dry matter weight and grain yield of N2 increased by 33–52% (P ≤ 0.05 and 6–32% (P ≤ 0.05, respectively, compared with other treatments. During the growing from silking (R1 to milk (R3 stage, LAI of N0 and N1 were 35–38% (P ≤ 0.05 and 9–23% (P ≤ 0.05 less than that of N2, respectively. Chlorophyll SPAD value of N0 and N1 were 13–22% (P ≤ 0.05 and 5–11% (P ≤ 0.05 lower than that of N2. There was no significant difference in LAI and chlorophyll SPAD value between N2 and N3 during the period from R1 to R3 (P > 0.05. The net photosynthetic rate (Pn, maximal quantum efficiency of PSII (Fv/Fm and quantum efficiency of PSII (ΦPSII were higher with the increase of N rate up to N2 (P ≤ 0.05, and those of N3 were significantly less than N2 (P ≤ 0.05. In compared with N2, the chloroplast configuration of N0 and N1 became elliptical, almost circular or irregular. The membrane of chloroplast and thylakoid resolved with growing stage, and the number of chloroplast per cell and lamellae per grana decreased under N0 and N1 treatment (P ≤ 0.05. Under N0 and N1 treatments, summer maize had more negative photosynthetic characteristics. The more number of osmium granule and vesicle and the larger gap between lamellae were shown in N3

Biochemical and ultrastructural processing of [125I]epidermal growth factor in rat epidermis and hair follicles: accumulation of nuclear label

International Nuclear Information System (INIS)

Green, M.R.; Mycock, C.; Smith, C.G.; Couchman, J.R.

1987-01-01

Although the intracellular ultrastructural processing of epidermal growth factor (EGF) and its receptor have been described in cell culture systems, very few studies have examined this phenomenon in intact tissues. We have examined the ultrastructural and biochemical handling of [ 125 I]EGF in the epidermis and hair follicle bulb of intact, viable, 3- to 5-day-old rat skin the EGF receptor distribution of which has already been documented and in which EGF has been shown to be biologically active. After incubation of explants with 10 nM [ 125 I]EGF for 2.5 h at 25 degrees or 37 degrees C, radiolabel was detected over the basal cells of the epidermis and hair follicle outer root sheath, confirming previous light microscope observations. More specifically, silver grains were observed near coated and uncoated plasma membrane and coated membrane invaginations, Golgi apparatus, lysosomal structures, and nuclei. Sodium azide inhibited internalization of label, whereas a series of lysosomal inhibitors (chloroquine, monensin, and iodoacetamide) caused a slight increase in silver grains associated with lysosomal vesicles and a decrease in nuclear label. Biochemical analysis indicated that greater than 35% of radioactivity following incubation at 37 degrees C was in the form of degraded [ 125 I]EGF fragments and that inclusion of chloroquine, monensin, and iodoacetamide reduced this value to 20.8%, 8.6%, and 4.0%, respectively. In addition, chloramine T-prepared [ 125 I]EGF was found to be covalently cross-linked with low efficiency to a protein having the molecular weight of the EGF receptor. These data are discussed in the light of the effects of EGF on epithelial cell proliferation in skin

Biochemical and ultrastructural changes in pollen of Zea mays L. grown under enhanced UV-B radiation

International Nuclear Information System (INIS)

Santos, A.; Almeida, J.M.; Santos, I.; Salema, R.

1998-01-01

The influence of ultraviolet-B (UV-B) radiation on the development of the male gametophyte was studied in Zea mays L. cv. LG12 grown in a growth chamber under PAR light supplemented with UV-B radiation and compared with a second set of plants grown under PAR light. Pollen samples collected from both groups of plants were cultured on germination medium and it was found that UV-B had no effect on pollen germination. Total pollen protein content was not affected but UV-B absorbing pigments increased. Some ultrastructural alterations were observed in pollen and pollen tubes, in particular large amounts of electron dense deposits were seen throughout the cytoplasm and in association with the pollen wall. In mature spikes of UV-B treated plants, anthers retained numerous pollen grains in their loculi while anthers of control plants were almost empty. UV-B treatment delayed flowering by 2±3 d. These results show that UV-B treatment of maize plants interferes with flowering, pollen ultrastructure and anther maturation even though pollen germination is unaffected. The significant increase of UV-B absorbing pigments in pollen grains could represent a defence mechanism that enables plants to complete their reproductive cycle. (author)

Ultrastructural aspects of experimental cryptosporidiosis in pigs Aspectos ultraestruturais da criptosporidiose experimental em suínos

Directory of Open Access Journals (Sweden)

A.P.F.R.L. Bracarense

1999-10-01

Full Text Available The aim of this work was to determine ultrastructural changes on the intestinal mucosa and associated lymphoid tissues after an experimental infection with Cryptosporidium sp. Twelve piglets dosed orally with 1×10(6 oocysts were slaughtered on days 3, 6, 9 and 12 after inoculation. The ultrastructural lesions in the intestinal cells were irregular with thickened microvilli, cytoplasmic protrusions and vacuolation, swollen mitochondria, hypertrophic organelles and nuclei. The lymphocytes of the Peyer’s patches occasionally were mitotic with a larger number of lymphoblasts in the inoculated animals.O presente estudo teve por objetivo investigar as alterações ultraestruturais da mucosa intestinal e do tecido linfóide associado na inoculação experimental de Cryptosporidium sp. Doze leitões foram inoculados experimentalmente por via oral com 1×10(6 oocistos e sacrificados 3, 6, 9 e 12 dias depois. Ao exame ultraestrutural de células intestinais observou-se espessamento e irregularidade de microvilosidades, citoplasma vacuolizado e com protrusões, edema mitocondrial, hipertrofia de organelas citoplasmáticas e do núcleo. Nas placas de Peyer observou-se ocasionalmente mitose de células linfóides, verificando-se maior número de células blásticas.

Histopathology of Middle East respiratory syndrome coronovirus (MERS-CoV) infection - clinicopathological and ultrastructural study.

Science.gov (United States)

Alsaad, Khaled O; Hajeer, Ali H; Al Balwi, Mohammed; Al Moaiqel, Mohammed; Al Oudah, Nourah; Al Ajlan, Abdulaziz; AlJohani, Sameera; Alsolamy, Sami; Gmati, Giamal E; Balkhy, Hanan; Al-Jahdali, Hamdan H; Baharoon, Salim A; Arabi, Yaseen M

2018-02-01

The pathogenesis, viral localization and histopathological features of Middle East respiratory syndrome - coronavirus (MERS-CoV) in humans are not described sufficiently. The aims of this study were to explore and define the spectrum of histological and ultrastructural pathological changes affecting various organs in a patient with MERS-CoV infection and represent a base of MERS-CoV histopathology. We analysed the post-mortem histopathological findings and investigated localisation of viral particles in the pulmonary and extrapulmonary tissue by transmission electron microscopic examination in a 33-year-old male patient of T cell lymphoma, who acquired MERS-CoV infection. Tissue needle biopsies were obtained from brain, heart, lung, liver, kidney and skeletal muscle. All samples were collected within 45 min from death to reduce tissue decomposition and artefact. Histopathological examination showed necrotising pneumonia, pulmonary diffuse alveolar damage, acute kidney injury, portal and lobular hepatitis and myositis with muscle atrophic changes. The brain and heart were histologically unremarkable. Ultrastructurally, viral particles were localised in the pneumocytes, pulmonary macrophages, renal proximal tubular epithelial cells and macrophages infiltrating the skeletal muscles. The results highlight the pulmonary and extrapulmonary pathological changes of MERS-CoV infection and provide the first evidence of the viral presence in human renal tissue, which suggests tissue trophism for MERS-CoV in kidney. © 2017 John Wiley & Sons Ltd.

[Ultrastructural changes of myelinated fibers in the brain in continuous and attack-like paranoid schizophrenia].

Science.gov (United States)

Uranova, N A; Kolomeets, N S; Vikhreva, O V; Zimina, I S; Rakhmanova, V I; Orlovskaya, D D

Previously the authors have reported the ultrastructural pathology of myelinated fibers (MF) in the brain in schizophrenia. The aim of the present study was to compare the effect of disease course on ultrastructural changes of MF. Postmortem electron microscopic morphometric study of MF was performed in the prefrontal cortex, caudate nucleus and hippocampus in 19 cases of paranoid schizophrenia. Fourteen cases of continuous schizophrenia, 5 cases of attack-like schizophrenia and 25 normal matched control cases were studied. The proportion (percentage) of pathological MF was estimated in the prefrontal cortex, layer 5, CA3 area of hippocampus, pyramidal layer, and in the head of the caudate nucleus. The percentage of MF having axonal atrophy and swelling of periaxonal oligodendrocyte process was significantly higher in both continuous and attack-like schizophrenia in all brain structures studied as compared to the control group. In the hippocampus and caudate nucleus, this parameter was increased significantly in attack-like schizophrenia as compared to continuous schizophrenia. In the prefrontal cortex. The percentage of the pathological MF having signs of deformation and destruction of myelin sheaths increased significantly only in continuous schizophrenia as compared to the control group. MF pathology is similar in attack-like and continuous paranoid schizophrenia but differ by the degree of severity of pathological MF. Abnormalities in MF contribute to the disconnectivity between the prefrontal cortex, caudate nucleus and hippocampus.

Gamma radiation effect on the mitochondria ultrastructure in different radiosensitive types of cotton plants

Energy Technology Data Exchange (ETDEWEB)

Arslanov, S V

1973-01-01

When germinated seeds are irradiated with a dose of 10 krad, the mitochondrial ultrastructure is disrupted in the early-ripening 1306-DV and the late-ripening S-1622 varieties of the cotton-plant. The mitochondria exhibited swelling, breakdown of internal structure and vacuolation. In the S-1622 variety the mitochondria shrink owing to their small number and larger size and to the smaller number of cristae. Changes in the ultrafine organization of mitochondria lead to inhibition of carbohydrate oxidation through the Krebs cycle and intensification of oxidation through the pentosophosphate cycle.

Ozone effects on radish (Raphanus sativus L. cv. Cherry Belle): gradient of ultrastructural changes

Energy Technology Data Exchange (ETDEWEB)

Athanassious, R.

1980-01-01

Ultrastructural changes produced by low ( less than or equal to 0.5 ppm) levels of ozone may be attributed to water deficit resulting from injury to the sensitive paravenial cells. The drastic alterations, resulting from high ( greater than or equal to 0.5 ppm) ozone concentrations, were apparently due to more direct effects. Although differential fixation images of membranes in control and ozone treated leaves were not obtained the significance of ozone attacking the olefinic groups of fatty acids in the membrane bilayer should not be completely ignored. 19 references, 12 figures.

Using team cognitive work analysis to reveal healthcare team interactions in a birthing unit.

Science.gov (United States)

Ashoori, Maryam; Burns, Catherine M; d'Entremont, Barbara; Momtahan, Kathryn

2014-01-01

Cognitive work analysis (CWA) as an analytical approach for examining complex sociotechnical systems has shown success in modelling the work of single operators. The CWA approach incorporates social and team interactions, but a more explicit analysis of team aspects can reveal more information for systems design. In this paper, Team CWA is explored to understand teamwork within a birthing unit at a hospital. Team CWA models are derived from theories and models of teamwork and leverage the existing CWA approaches to analyse team interactions. Team CWA is explained and contrasted with prior approaches to CWA. Team CWA does not replace CWA, but supplements traditional CWA to more easily reveal team information. As a result, Team CWA may be a useful approach to enhance CWA in complex environments where effective teamwork is required. This paper looks at ways of analysing cognitive work in healthcare teams. Team Cognitive Work Analysis, when used to supplement traditional Cognitive Work Analysis, revealed more team information than traditional Cognitive Work Analysis. Team Cognitive Work Analysis should be considered when studying teams.

Using team cognitive work analysis to reveal healthcare team interactions in a birthing unit

Science.gov (United States)

Ashoori, Maryam; Burns, Catherine M.; d'Entremont, Barbara; Momtahan, Kathryn

2014-01-01

Cognitive work analysis (CWA) as an analytical approach for examining complex sociotechnical systems has shown success in modelling the work of single operators. The CWA approach incorporates social and team interactions, but a more explicit analysis of team aspects can reveal more information for systems design. In this paper, Team CWA is explored to understand teamwork within a birthing unit at a hospital. Team CWA models are derived from theories and models of teamworkand leverage the existing CWA approaches to analyse team interactions. Team CWA is explained and contrasted with prior approaches to CWA. Team CWA does not replace CWA, but supplements traditional CWA to more easily reveal team information. As a result, Team CWA may be a useful approach to enhance CWA in complex environments where effective teamwork is required. Practitioner Summary: This paper looks at ways of analysing cognitive work in healthcare teams. Team Cognitive Work Analysis, when used to supplement traditional Cognitive Work Analysis, revealed more team information than traditional Cognitive Work Analysis. Team Cognitive Work Analysis should be considered when studying teams PMID:24837514

Histological and ultrastructural effect of an Nd:YAG pulsed laser beam on dental hard tissue and pulp

Science.gov (United States)

Vignato, Costantino; Vignato, Giuseppe; Nardelli, Antonella; Baldan, Arianna; Mason, Pier N.

1994-09-01

The purpose of this study was to determine histological and ultrastructural modifications produced by an Nd:YAG pulsed laser beam after an in vivo exposure of human molars. Using a Nd:YAG pulsed laser beam delivered by a 600 micrometers optical fiber and concurrent air and water cooling spray, 14 human third molars with artificial first class cavities were exposed at different power levels (6, 7, and 8 W). All the teeth were extracted at different time periods between 10 and 25 days and prepared for histological examination. The results of the histological examination showed no evidence of degeneration or necrosis of the pulpar tissue. Analysis of the dentinal surfaces after exposure demonstrated that the dentinal tubules are completely closed due to the melted dentin. In conclusion a Nd:YAG pulsed laser beam with an air and water cooling spray is safe for treatments of class I decay and no necrosis or degeneration of the pulp was found for laser powers of 6, 7, and 8 W.

Implications of obesity for tendon structure, ultrastructure and biochemistry: a study on Zucker rats.

Science.gov (United States)

Biancalana, Adriano; Velloso, Lício Augusto; Taboga, Sebastião Roberto; Gomes, Laurecir

2012-02-01

The extracellular matrix consists of collagen, proteoglycans and non-collagen proteins. The incidence of obesity and associated diseases is currently increasing in developed countries. Obesity is considered to be a disease of modern times, and genes predisposing to the disease have been identified in humans and animals. The objective of the present study was to compare the morphological and biochemical aspects of the deep digital flexor tendon of lean (Fa/Fa or Fa/fa) and genetically obese (fa/fa) Zucker rats. Ultrastructural analysis showed the presence of lipid droplets in both groups, whereas disorganized collagen fibril bundles were observed in obese animals. Lean animals presented a larger amount of non-collagen proteins and glycosaminoglycans than obese rats. We propose that the overweight and lesser physical activity in obese animals may have provoked the alterations in the composition and organization of extracellular matrix components but a genetic mechanism cannot be excluded. These alterations might be related to organizational and structural modifications in the collagen bundles that influence the mechanical properties of tendons and the progression to a pathological state. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of heavy metals on Cyanothece sp. CCY 0110 growth, extracellular polymeric substances (EPS) production, ultrastructure and protein profiles.

Science.gov (United States)

Mota, Rita; Pereira, Sara B; Meazzini, Marianna; Fernandes, Rui; Santos, Arlete; Evans, Caroline A; De Philippis, Roberto; Wright, Phillip C; Tamagnini, Paula

2015-04-29

The effects of several heavy metals on the growth/survival, EPS production, ultrastructure and protein profiles of the highly efficient extracellular polymeric substances (EPS)-producer cyanobacterium Cyanothece sp. CCY 0110 were evaluated. Our results clearly show that each heavy metal affects the cells in a particular manner, triggering distinctive responses. Concerning chronic exposure, cells were more affected by Cu(2+) followed by Pb(2+), Cd(2+), and Li(+). The presence of metal leads to remarkable ultrastructural changes, mainly at the thylakoid level. The comparison of the proteomes (iTRAQ) allowed to follow the stress responses and to distinguish specific effects related to the time of exposure and/or the concentration of an essential (Cu(2+)) and a non-essential (Cd(2+)) metal. The majority of the proteins identified and with fold changes were associated with photosynthesis, CO2 fixation and carbohydrate metabolism, translation, and nitrogen and amino acid metabolism. Moreover, our results indicate that during chronic exposure to sub-lethal concentrations of Cu(2+), the cells tune down their metabolic rate to invest energy in the activation of detoxification mechanisms, which eventually result in a remarkable recovery. In contrast, the toxic effects of Cd(2+) are cumulative. Unexpectedly, the amount of released polysaccharides (RPS) was not enhanced by the presence of heavy metals. This work shows the holistic effects of different heavy metals on the cells of the highly efficient EPS-producer the cyanobacterium Cyanothece sp. CCY 0110. The growth/survival, EPS production, ultrastructure, protein profiles and stress response were evaluated. The knowledge generated by this study will contribute to the implementation of heavy-metal removal systems based on cyanobacteria EPS or their isolated polymers. Copyright © 2015. Published by Elsevier B.V.

Low tendon stiffness and abnormal ultrastructure distinguish classic Ehlers-Danlos syndrome from benign joint hypermobility syndrome in patients

DEFF Research Database (Denmark)

Nielsen, Rie Harboe; Couppé, Christian; Jensen, Jacob Kildevang

2014-01-01

There is a clinical overlap between classic Ehlers-Danlos syndrome (cEDS) and benign joint hypermobility syndrome (BJHS), with hypermobility as the main symptom. The purpose of this study was to investigate the role of type V collagen mutations and tendon pathology in these 2 syndromes. In patients...... and abnormal ultrastructure distinguish classic Ehlers-Danlos syndrome from benign joint hypermobility syndrome in patients....

Transport, ultrastructural localization, and distribution of chemical forms of lead in radish (Raphanus sativus L.).

Science.gov (United States)

Wang, Yan; Shen, Hong; Xu, Liang; Zhu, Xianwen; Li, Chao; Zhang, Wei; Xie, Yang; Gong, Yiqin; Liu, Liwang

2015-01-01

Lead (Pb), a ubiquitous but highly toxic heavy metal (HM), is harmful to human health through various pathways including by ingestion of contaminated vegetables. Radish is a worldwide root vegetable crop with significant health and nutritional benefits. However, little is known about Pb translocation and distribution within radish plants after its uptake by the roots. In this study, Pb stress was induced using Pb(NO3)2 in hydroponic culture, aiming to characterize the transport, ultrastructural localization, and distribution of chemical forms of Pb in different tissues of radish. The results showed that the majority of Pb (85.76-98.72%) was retained in underground organs including lateral roots, root heads and taproot skins, while a small proportion of Pb was absorbed by root flesh (0.44-1.56%) or transported to the shoot (1.28-14.24%). A large proportion of Pb (74.11-99.30%) was integrated with undissolved Pb oxalate, protein and pectates forming Pb-phosphate complexes. Moreover, a low-Pb-accumulating line of radish showed a higher proportion of Pb in water-soluble form compared with a high-Pb-accumulating line. Subcellular distribution analysis showed that a large proportion of Pb was bound to cell wall fraction in lateral roots (71.08-80.40%) and taproot skin (46.22-77.94%), while the leaves and roots had 28.36-39.37% and 27.35-46.51% of Pb stored in the soluble fraction, respectively. Furthermore, transmission electron microscopy (TEM) revealed Pb precipitates in intercellular space, cell wall, plasma lemma and vacuoles. Fractionation results also showed the accumulation of Pb on the cell wall, intercellular space and vacuole, and low uptake of undissolved Pb oxalate, protein, pectates and Pb-phosphate complexes, which might be due to low transport efficiency and Pb tolerance of radish. These findings would provide insight into molecular mechanism of Pb uptake and translocation in radish and facilitate development of low-Pb-content cultivars in root vegetable

Transport, ultrastructural localization and distribution of chemical forms of lead in radish (Raphanus sativus L.

Directory of Open Access Journals (Sweden)

Yan eWang

2015-05-01

Full Text Available Lead (Pb, a ubiquitous but highly toxic heavy metal, is harmful to human health through various pathways including by ingestion of contaminated vegetables. Radish is a worldwide root vegetable crop with significant health and nutritional benefits. However, little is known about Pb translocation and distribution within radish plants after its uptake by the roots. In this study, Pb stress was induced using Pb(NO32 in hydroponic culture, aiming to characterize the transport, ultrastructural localization and distribution of chemical forms of Pb in different tissues of radish. The results showed that the majority of Pb (85.76–98.72% was retained in underground organs including lateral roots, root heads and taproot skins, while a small proportion of Pb was absorbed by root flesh (0.44–1.56% or transported to the shoot (1.28-14.24%. A large proportion of Pb (74.11–99.30% was integrated with undissolved Pb oxalate, protein and pectates forming Pb-phosphate complexes. Moreover, a low-Pb-accumulating line of radish showed a higher proportion of Pb in water-soluble form compared with a high-Pb-accumulating line. Subcellular distribution analysis showed that a large proportion of Pb was bound to cell wall fraction in lateral roots (71.08–80.40% and taproot skin (46.22–77.94%, while the leaves and roots had 28.36–39.37% and 27.35–46.51% of Pb stored in the soluble fraction, respectively. Furthermore, transmission electron microscopy (TEM revealed Pb precipitates in intercellular space, cell wall, plasma lemma and vacuoles. Fractionation results also showed the accumulation of Pb on the cell wall, intercellular space and vacuole, and low uptake of undissolved Pb oxalate, protein, pectates and Pb–phosphate complexes, which might be due to low transport efficiency and Pb tolerance of radish. These findings would provide insight into molecular mechanism of Pb uptake and translocation in radish and facilitate development of low

Echinobothrium chisholmae n. sp. (Cestoda, Diphyllidea) from the giant shovel-nose ray Rhinobatos typus from Australia, with observations on the ultrastructure of its scolex musculature and peduncular spines.

Science.gov (United States)

Jones, M K; Beveridge, I

2001-09-01

Echinobothrium chisholmae n. sp. is described from Rhinobatos typus Bennett (Rhinobatidae), collected from Heron Island, Great Barrier Reef, Australia. E. chisholmae differs from all congeners in possessing 11 hooks in each dorsal and ventral group on the rostellum and groups of 3-6 hooklets on either side of the hooks. A single metacestode of E. chisholmae was collected from the decapod crustacean Penaeus longistylus Kubo. Yellow pigmentation of the cephalic peduncle in immature adults is caused by the accumulation of large vesicles in the distal cytoplasm of the tegument. The vesicles probably provide materials for spine formation. Ultrastructural examination of the rostellar musculature revealed that the muscles are stratified (striated-like), consisting of a periodic repetition of sarcomeres separated by perforated Z-like lines that are oblique to the long axes of the myofilaments.

Behavioral, Ultrastructural and Chemical Studies on the Honeydew and Waxy Secretions by Nymphs and Adults of the Asian Citrus Psyllid Diaphorina citri (Hemiptera: Psyllidae)

Science.gov (United States)

Ammar, El-Desouky; Alessandro, Rocco; Shatters Jr, Robert G.; Hall, David G.

2013-01-01

The Asian citrus psyllid (ACP), Diaphorina citri (Hemiptera: Psyllidae) is the primary vector of the bacterium causing citrus huanglongbing (citrus greening), the most serious disease of citrus worldwide. Psyllids and other hemipterans produce large amounts of honeydew, which has been used previously as an indicator of phloem sap composition and insect feeding or metabolism. Behavioral, ultrastructural and chemical studies on ACP, its honeydew and waxy secretions showed important differences between nymphs, males and females, and suggested some mechanisms by which the psyllids, especially nymphs and adult females, can minimize their contamination with honeydew excretions. The anal opening in ACP, near the posterior end of the abdomen, is on the ventral side in nymphs and on the dorsal side in adult males and females. Video recordings showed that adult males produce clear sticky droplets of honeydew gently deposited behind their body on the leaf surface, whereas adult females produce whitish honeydew pellets powerfully propelled away from the female body, probably to get their excretions away from eggs and newly hatched nymphs. ACP nymphs produce long ribbons or tubes of honeydew that frequently stay attached to the exuviae after molting, or drop when feeding on the lower side of citrus leaves. Furthermore, honeydew excretions of both nymphs and adult females are covered with a thin layer of whitish waxy material ultrastructurally composed of a convoluted network of long fine filaments or ribbons. This material is extruded from intricate arrays of wax pores in the circumanal ring (around the anus) that is found in nymphs and females but not in males of ACP or other psyllid species. Infrared microscopy and mass spectroscopy revealed that, in addition to various sugars, honeydew excretions of ACP nymphs and females are covered with a thin layer of wax similar in profile to ester waxes. PMID:23762268

Behavioral, ultrastructural and chemical studies on the honeydew and waxy secretions by nymphs and adults of the Asian citrus psyllid Diaphorina citri (Hemiptera: Psyllidae.

Directory of Open Access Journals (Sweden)

El-Desouky Ammar

Full Text Available The Asian citrus psyllid (ACP, Diaphorina citri (Hemiptera: Psyllidae is the primary vector of the bacterium causing citrus huanglongbing (citrus greening, the most serious disease of citrus worldwide. Psyllids and other hemipterans produce large amounts of honeydew, which has been used previously as an indicator of phloem sap composition and insect feeding or metabolism. Behavioral, ultrastructural and chemical studies on ACP, its honeydew and waxy secretions showed important differences between nymphs, males and females, and suggested some mechanisms by which the psyllids, especially nymphs and adult females, can minimize their contamination with honeydew excretions. The anal opening in ACP, near the posterior end of the abdomen, is on the ventral side in nymphs and on the dorsal side in adult males and females. Video recordings showed that adult males produce clear sticky droplets of honeydew gently deposited behind their body on the leaf surface, whereas adult females produce whitish honeydew pellets powerfully propelled away from the female body, probably to get their excretions away from eggs and newly hatched nymphs. ACP nymphs produce long ribbons or tubes of honeydew that frequently stay attached to the exuviae after molting, or drop when feeding on the lower side of citrus leaves. Furthermore, honeydew excretions of both nymphs and adult females are covered with a thin layer of whitish waxy material ultrastructurally composed of a convoluted network of long fine filaments or ribbons. This material is extruded from intricate arrays of wax pores in the circumanal ring (around the anus that is found in nymphs and females but not in males of ACP or other psyllid species. Infrared microscopy and mass spectroscopy revealed that, in addition to various sugars, honeydew excretions of ACP nymphs and females are covered with a thin layer of wax similar in profile to ester waxes.

Skin toxicity of jet fuels: ultrastructural studies and the effects of substance P

International Nuclear Information System (INIS)

Monteiro-Riviere, Nancy A.; Inman, Alfred O.; Riviere, Jim E.

2004-01-01

Topical exposure to jet fuel is a significant occupational hazard. Recent studies have focused on dermal absorption of fuel and its components, or alternatively, on the biochemical or immunotoxicological sequelae to exposure. Surprisingly, morphological and ultrastructural analyses have not been systematically conducted. Similarly, few studies have compared responses in skin to that of the primary target organ, the lung. The focus of the present investigation was 2-fold: first, to characterize the ultrastructural changes seen after topical exposure to moderate doses (335 or 67 μl/cm 2 ) of jet fuels [Jet A, Jet Propellant (JP)-8, JP-8+100] for up to 4 days in pigs, and secondly, to determine if co-administration of substance P (SP) with JP-8 jet fuel in human epidermal keratinocyte cell cultures modulates toxicity as it does to pulmonary toxicity in laboratory animal studies. The primary change seen after exposure to all fuels was low-level inflammation accompanied by formation of lipid droplets in various skin layers, mitochondrial and nucleolar changes, cleft formation in the intercellular lipid lamellar bilayers, as well as disorganization in the stratum granulosum-stratum corneum interface. An increased number of Langerhans cells were also noted in jet fuel-treated skin. These changes suggest that the primary effect of jet fuel exposure is damage to the stratum corneum barrier. SP administration decreased the release of interleukin (IL)-8 normally seen in keratinocytes after JP-8 exposure, a response similar to that reported for SP's effect on JP-8 pulmonary toxicity. These studies provide a base upon which biochemical and immunological data collected in other model systems can be compared

Histology, Histochemistry And Ultrastructure Of The Oviducts And Seminal Receptacle Of Tropidurus Itambere (rodrigues, 1987) (reptilia: Tropiduridae)

OpenAIRE

Ferreira A.; Dolder H.

2007-01-01

The present study found new information regarding the histology, histochemistry and ultrastructure of the oviduct of Tropidurus itambere, an inhabitant of the Brazilian Atlantic forest. Three differentiated histological regions constitute the oviduct: the infundibulum, as its main characteristic, has many tubuloalveolar glands; the uterine region is remarkable for many mucous glands, just below the epithelium; the vagina, near to the cloacal opening, is characterized by an epithelium with inf...

Ultrastructure of the body wall of Cystidicoloides ephemeridarum (Nematoda, Cystidicolidae) in relation to the histopathology of this nematode in salmonids

Czech Academy of Sciences Publication Activity Database

Frantová, Denisa; Moravec, František

2003-01-01

Roč. 91, č. 2 (2003), s. 100-108 ISSN 0932-0113 R&D Projects: GA AV ČR KJB6022305 Grant - others:GA FRVŠ(CZ) 1262/2002 Institutional research plan: CEZ:AV0Z6022909 Keywords : Nematoda * ultrastructure Subject RIV: EA - Cell Biology Impact factor: 1.000, year: 2003

Colorimeter and scanning electron microscopy analysis of teeth submitted to internal bleaching.

Science.gov (United States)

Martin-Biedma, Benjamin; Gonzalez-Gonzalez, Teresa; Lopes, Manuela; Lopes, Luis; Vilar, Rui; Bahillo, José; Varela-Patiño, Purificación

2010-02-01

This in vitro study compared the tooth color and the ultrastructure of internal dental tissues before and after internal bleaching. Sodium perborate was placed in the pulp chamber of endodontically treated molars and sealed with intermediate restorative material. The test samples were stored in a physiologic solution, and the bleaching agent was replaced every 7 days. A control group was used. After 1 month, the colors of the test and control samples were measured with a colorimeter, and the internal surfaces were observed under field emission scanning electron microscopy (FESEM). Statistically significant differences were found between the test and control sample colors. The FESEM ultrastructure analysis of the internal enamel and dentin surfaces did not show any changes after the internal bleaching. The results of the present study show that sodium perborate is effective in bleaching nonvital teeth and does not produce ultrastructural changes in the dental tissues. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Grappling archaea: ultrastructural analyses of an uncultivated, cold-loving archaeon and its biofilm

Directory of Open Access Journals (Sweden)

Alexandra ePerras

2014-08-01

Full Text Available Similarly to Bacteria, Archaea are microorganisms that interact with their surrounding environment in a versatile manner. To date, interactions based on cellular structure and surface appendages have mainly been documented using model systems of cultivable archaea under laboratory conditions. Here, we report on the microbial interactions and ultrastructural features of the uncultivated SM1 Euryarchaeon, which is highly dominant in its biotope. Therefore, biofilm samples taken from the Sippenauer Moor, Germany, were investigated via transmission electron microscopy (TEM; negative staining, thin-sectioning and scanning electron microscopy (SEM in order to elucidate the fine structures of the microbial cells and the biofilm itself. The biofilm consisted of small archaeal cocci (0.6 µm diameter, arranged in a regular pattern (1.2-2.0 µm distance from cell to cell, whereas each archaeon was connected to 6 other archaea on average. Extracellular polymeric substances (EPS were limited to the close vicinity of the archaeal cells, and specific cell surface appendages (hami, Moissl et al., 2005 protruded beyond the EPS matrix enabling microbial interaction by cell-cell contacts among the archaea and between archaea and bacteria. All analyzed hami revealed their previously described architecture of nano-grappling hooks and barb-wire basal structures. Considering the archaeal cell walls, the SM1 Euryarchaea exhibited a double-membrane, which has rarely been reported for members of this phylogenetic domain. Based on these findings, the current generalized picture on archaeal cell walls needs to be revisited, as archaeal cell structures are more complex and sophisticated than previously assumed, particularly when looking into the uncultivated majority.

Acute erythroblastic leukemia presenting as acute undifferentiated leukemia: a report of two cases with ultrastructural features.

Science.gov (United States)

Reiffers, J; Bernard, P; Larrue, J; Dachary, D; David, B; Boisseau, M; Broustet, A

1985-01-01

This report describes two elderly patients with acute leukemia in which blast cells were undifferentiated with conventional light microscopy (L.M.) and cytochemistry. Blast cells were identified as belonging to the erythroblastic line by their ultrastructural features: glycogen deposits, lipidic vacuoles, cytoplasmic ferritin molecules and rhopheocytotic invagination. Moreover, blast cells were surrounding a central macrophage. Thus, these two patients had acute erythroblastic leukemia which differs from erythroleukemia (M6 of FAB classification) in which blast cells present myeloblastic characteristics.